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1

Talebizadeh, Nooshin. "Caspase-3 in lens epithelium." Doctoral thesis, Uppsala universitet, Oftalmiatrik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-267543.

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Purpose: To model the time evolution of active caspase-3 protein expression in a healthy lens, and in a lens exposed to UVR-300 nm (UVR-B). To develop an automated method to classify the fluorescent signal of biomarkers in the lens epithelial cells. Methods: Six-week old Sprague-Dawley rats were used. Firstly, expression of active caspase-3 was studied in the lens epithelium of healthy rats. Secondly, rats were unilaterally exposed in vivo to 1 kJ/m2 UVR-B for 15 minutes. At 0.5, 8, 16, and 24 hours after the UVR-B exposure, the exposed and the contralateral non-exposed lenses were removed. Immunohistochemistry was done on three mid-sagittal sections from each lens. The florescent labelling for active caspase-3 in each lens section was counted three times. The time evolution of active caspase-3 expression in response to UVR-B exposure was modelled as a function of cell position in the lens epithelium. An automated objective method was developed to quantify the lens epithelial cells and to classify the fluorescent signal of active caspase-3. Active caspase-3 was selected as a model signal. Results: Active caspase-3 was abundant in the anterior pole of the normal lenses. Spatial distribution of active caspase-3 labelling in the lens epithelium was fitted to a logistic model. The probability of active caspase-3 expression was higher in the UVR-B exposed lenses (95% CI = 0.12 ± 0.01). There was no difference in the expression of active caspase-3 between the 0.5 and the 24 hours groups or between the 8 and the 16 hours groups. A difference was noted, when comparing the 0.5 and 24 hours groups with the 8 and 16 hours groups (Test statistic 7.01, F1;36;0.95= 4.11). Exposure to UVR-B has an impact on the average probability of labelling for active caspase-3 as a function of cell position. The probability of labelling as a function of cell number also varied as a function of time after UVR-B exposure. The automated method counted the lens epithelial cells and estimated the proportion of active caspase-3 labelling in the lens epithelium. Conclusions: Active caspase-3 is present in the healthy lens epithelial cells. Active caspase-3 exhibits higher expression at the anterior pole of the lens and the expression decreases towards the periphery. After UVR-B exposure, the expression of active caspase-3 in the lens epithelium increases with a peak of expression occurring around 16 hours after exposure. The average probability of labelling in the lens epithelium is dependent on both the UVR-B exposure and the time period elapsed after the exposure. The automated method enables objective and fast quantification of lens epithelial cells and the expression of fluorescent signal in the lens cells.
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2

Shao, Wei 1970. "Identification of caspase-1 and caspase-3 substrates and study on caspase-1 substrates in glycolytic pathway." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100248.

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Apoptosis is executed by caspase-mediated cleavage of various proteins. Elucidating the consequence of substrate cleavage provides us with insight into cell death and other biological processes. In this study, we applied the diagonal gel approach, a proteomic strategy, to identify substrates of the inflammatory caspase, caspase-1 and the cell death executioner caspase, caspase-3. Our results showed significant overlap between the substrates cleaved by both caspase-1 and -3. Such substrates are implicated in common cellular functions, including maintenance of the cytoskeleton, folding of proteins, translation, glycolysis, bioenergetics, signaling and trafficking. An important finding is that many glycolysis enzymes were targeted specifically by caspase-1. Processing of these glycolysis enzymes by caspase-1 was confirmed by cleaving in vitro transcribed and translated substrates with recombinant caspase-1. We have focused our further analysis on certain glycolysis enzymes. We have characterized the caspase-1 cleavage site in GAPDH. Point mutation of the Aspartic acid at position 189 to Alanine (D189A) in GAPDH blocked its cleavage by caspase-1. In vivo, in a mice model of septic shock, characterized by hyperactivation of caspase-1, we observed depletion of the full-length forms of these glycolysis enzymes in the diaphragm muscle. Further studies in caspase-1 deficient mice will confirm whether this depletion, in caspase-1 proficient mice, was due to caspase-1 processing of the glycolysis enzymes. This provides a direct link between caspase-1 activation and inhibition of glycolysis, which might have important implications on loss of muscle contractility in septic shock.
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3

Voss, Oliver H. "Regulation of Cell Fate by Caspase-3." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281536983.

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4

Woo, Minna. "Understanding the role of caspase-3 in vivo." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ58614.pdf.

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5

Riedl, Stefan. "Röntgenstrukturanalyse der Caspase-3-XIAP-BIR2, Caspase-7-XIAP-BIR2-Komplexe und der Procaspase-7." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964905426.

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6

Larsen, Brian D. "Role of Caspase 3/Caspase Activated DNase induced DNA Strand Breaks during Skeletal Muscle Differentiation." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/20709.

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Cell fate decisions incorporate distinct and overlapping mechanisms. The activity of caspase 3 was initially understood to be a cell death restricted event, however numerous studies have implicated this enzyme in the regulation of both differentiation and proliferation. How the activity of caspase 3 promotes a non-death cell fate remains unclear. Here we examine the role caspase 3 activity plays during skeletal muscle differentiation; in particular we explore the hypothesis that the mechanism of inducing DNA strand breaks during cell death is also a key feature of differentiation, albeit with a distinctly different outcome. We delineate the transient formation of Caspase 3/Caspase activated DNase (CAD) dependent DNA strand breaks during differentiation. The formation of these breaks is essential for differentiation and the regulation of specific genes. In particular expression of the cell cycle inhibitor p21 is related to the formation of a DNA strand break within the gene’s promoter element. Further, we explored the genome wide association of CAD using Chromatin Immunoprecipitation coupled to high through put sequencing (ChIP-seq). This approach identified a potential role for Caspase3/CAD in regulating the expression of Pax7. Here, a CAD directed DNA strand break in the Pax7 gene is correlated with decreased Pax7 expression, an outcome that has been shown to be critical for progress of the myogenic differentiation program. The regulation of Pax7 expression through a CAD induced DNA strand break raises an intriguing connection between this regulation and oncogenic transformation observed in alveolar rhabdomyosarcoma. The putative site of CAD induced DNA strand breaks that promote decreased Pax7 expression during differentiation corresponds to site of chromosomal translocations responsible for Pax7 fusion events in alveolar rhabdomyosarcoma.
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7

Jahani-asl, Arezu. "Influence of phosphorylation on caspase-3-mediated Akt1 cleavage." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26931.

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Caspase-3, an executioner of apoptosis, is negatively regulated by X-linked inhibitor of apoptosis protein (XIAP), a determinant of cisplatin resistance. XIAP down-regulation in ovarian cancer cells or treatment with cisplatin induces caspase-3-mediated AKT cleavage and apoptosis, while XIAP over-expression suppresses this cleavage and increases phospho-AKT content. The identity of the caspase-3 cleavage site(s) in AM and the possible dependence of caspase-3-mediated cleavage on its phosphorylation status are unknown. The objectives of this thesis were to determine the caspase-3 cleavage site(s) in Akt1 and to examine the influence of phosphorylation on Akt1 cleavage in vitro. Our results suggested presence of three non-consensus (EEEE 117, EEMD119, DAKE398) and one consensus (DQDD456) cleavage sites, and posphorylation of Akt1 influenced the pattern of cleavage in a site-specific manner: Whereas cleavage at site "EEEE117" was facilitated by phosphorylation, that at sites "EEMD119 and DAKE398'' were attenuated. The biological significance of these observations requires future investigation.
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8

Turner, Claire. "The role of caspase-3 in drug-induced apoptosis." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342127.

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9

Beiche, Alexandra. "Expression von Caspasen in Kopf-Hals-Tumoren - immunhistochemischer Nachweis von Caspase 1, 2, 3 und Proliferationsmarker Ki67." Ulm : Universität Ulm, Medizinische Fakultät, 2000. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB9186905.

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10

Benetone, Maria Zilah. "Apoptose e proliferação na placenta de búfalas." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-23062006-182309/.

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A apoptose é um processo fisiológico que desempenha papel crucial no desenvolvimento, remodelagem e senescência teciduais, inclusive placentários. A placenta, enquanto órgão temporário, atravessa todas estas fases em aproximadamente 10 meses, na espécie bubalina. O crescimento da placenta e a nutrição fetal requerem altas taxas de renovação e diferenciação celulares, e a maturação placentária está relacionada à redução das células epiteliais das criptas carunculares maternas. As modificações morfológicas celulares decorrentes do processo de apoptose são fruto de eventos bioquímicos complexos promovidos por uma família de cisteína-proteases, as caspases, especialmente as caspases executoras, dentre as quais se destaca a caspase-3, capaz de degradar várias proteínas citoplasmáticas e nucleares. Durante a apoptose, ocorre a clivagem caspase-mediada da citoqueratina 18, proteína dos filamentos intermediários do citoesqueleto, e com isso a formação de um neoepítopo específico. Por meio de métodos imunoistoquímicos pode-se detectar a presença tanto deste neoepítopo, quanto da forma ativa da caspase-3, o que demonstra que a célula entrou em estágio irreversível de morte celular. Morfologicamente, algumas das principais alterações celulares observadas são condensação da cromatina, a degradação e fragmentação do DNA, a formação de ?blebs? (pregas/bolhas) na membrana plasmática, além da fragmentação celular em corpúsculos apoptóticos, os quais podem ser identificados em cortes corados pelo método de rotina hematoxilina e eosina, utilizando-se microscópio de imunofluorescência, devido à eosinofluorescência das células em apoptose. Assim como a apoptose, a proliferação celular participa no equilíbrio homeostático tissular. Neste estudo, pretende-se avaliar a ocorrência de apoptose e proliferação celular em 42 placentônios de diferentes animais em diversas fases gestacionais (2-10 meses de gestação), em tecidos fixados em 4% paraformoldeído, incluídos em paraplast e submetidos à imunoistoquímica (anticorpo monoclonal M30 CytoDeath; Caspase-3 Clivada; PCNA - antígeno de marcação nuclear), sendo também avaliada a presença de corpúsculos apoptóticos eosinofluorescentes nas amostras. Utilizando-se M30 e caspase-3 clivada pudemos constatar a ocorrência de apoptose nos epitélios uterino e trofoblástico, em células gigantes placentárias e, ocasionalmente, em células mesenquimais fetais, do estroma uterino e endoteliais. Não houve diferenças significativas (p<0.05) entre os métodos adotados, mas sim entre os estágios gestacionais. Para o M30, houve um aumento significante da apoptose do primeiro grupo (2-4.5 meses) em relação ao quarto grupo (9-10 meses); no caso da Caspase-3 Clivada houve um aumento estatísticamente significante (p<0.05) entre os três primeiros grupos (2-4.5; 5-6.5; e 7-8.5 meses de gestação, respectivamente) de animais em relação ao quarto grupo. Para o PCNA, ocorreu uma diminuição no número de células em proliferação dos dois primeiros grupos de animais em relação ao quarto grupo (p<0.05). A presença de corpúsculos apoptóticos eosinofluorescentes pôde ser observada em todas as amostras. Nossos resultados sugerem haver uma relação entre a ocorrência de apoptose e a maturação, senescência e liberação placentárias em ruminantes.
Apoptosis is a physiological process that plays a crucial role in the development, remodeling and aging of the placenta. The placenta is a temporary organ that undergoes growth and development, followed by senescence and death in 10 months in the buffalo species. Placental growth and fetal nutrition require high rates of cellular turnover and differentiation, and placental maturation is correlated to the reduction of the number of epithelial cells of the maternal crypts. The morphological changes of the apoptotic cells are product of complex variety of biochemical events promoted by a family of cystein-proteases, the caspases, mainly the effectors caspases, and among them the caspase-3, which is able to degrade cytoplasmic and nuclear proteins. During apoptosis, the caspase-mediated cleavage of cytokeratin 18, which is one of the first intermediate filament proteins of the cytoskeleton, leads to the formation of a specific neo-epitope. It is possible to detect the presence of this neo-epitope by immunohistochemistry, as well as the active form of caspase-3, showing that the cell has entered an irreversible stage of cell death. Morphologically, some of the main observed cellular alterations are condensation of the chromatin, degradation and spalling of the DNA, blebbing of the cell membrane and the formation of apoptotic bodies. These bodies can be identified in slides stained by hematoxilin and eosin with a fluorescent microscope, due to the eosinofluorescent property of the apoptotic cells. Like apoptosis, cellular proliferation also contributes to the tissue homeostasis. In the present study, we intend to evaluate the occurrence of apoptosis and cellular proliferation in 42 placentomes, collected from different animals in several gestacional phases (2-10 months of gestation), fixed in 4% paraformaldehyde, processed for embedding in paraplast and cut in sections, through immunohistochemistry (monoclonal antibody M30 CytoDeath; Cleaved Caspase-3; PCNA - antigen of nuclear proliferation). The presence of eosinofluorescent apoptotic bodies were also studied in the samples. M30 and Cleaved Caspase-3 allowed to show the occurrence of apoptosis in the uterine and trophoblastic ephitelium, in placental giant cells and, occasionally, in the fetal mesenquimal cells, in the uterine stroma and endothelium cells. There were no significant differences (p<0.05) between the adopted methods, although there were differences between the gestational phases studied. For M30, there was an increase of the number of apoptotic cells (p<0.05) from the first group (2-4.5 months) in relation to the fourth group of animals (9-10 months); for the Cleaved Caspase-3 there was a statistical significant increase (p<0.05) between the first three groups of animals (2-4.5; 5-6.5; and 7-8.5 months of gestation, respectively) and the last one. In relation to the PCNA, a decrease in the number of proliferative cells occurred from the first two groups of animals to the fourth group (p<0.05). The occurrence of eosinofluorescent apoptotic bodies was observed in all the samples studied . Our data suggest a relationship between apoptosis and the maturation, senescence and release of the ruminant placenta.
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11

Suria, Hamza. "Cytoskeletal disruption induces apoptosis by a Caspase-3 mediated mechanism." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ42101.pdf.

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12

Cabral, Maria Madalena Ribeiro. "Caspase 3: a potential marker for in vitro fertilization outcome." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11733.

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Mestrado em Biologia Molecular e Celular
Mundialmente é estimado que aproximadamente 70 milhões de casais tenham problemas de infertilidade, o que corresponde a um em cada sete casais em idade reprodutiva. O rápido aumento de problemas reprodutivos nas últimas décadas sugere uma maior probabilidade deste aumento ser devido a factores do estilo de vida e/ou ambientais, do que resultado de uma variação genética. Em Portugal 2,2% dos bébes nascidos resultam de técnicas de reprodução medicamente assistida. A transferência de vários embriões realizada, por vezes, no decurso destas técnicas pode resultar em gravidezes múltiplas, o que advém em complicações bem conhecidas para as mães e os bébes. São necessárias novas ferramentas de diagnóstico para que se possa transferir menos embriões com resultados similares ou melhores. Neste estudo foi investigado o impacto de vários factores do estilo de vida no potencial reprodutivo de 47 casais que recorreram a técnicas de reprodução medicamente assistida. Para além disso, foi realizada também, a correlação entre os níveis de expressão de um marcador da apoptose (caspase-3 clivada) nas células do cumulus do ovócito e a obtenção de uma gravidez (n=30). Uma concentração significativamente (p<0.01)) maior de caspase-3 clivada foi observada nas células do cumulus dos casais que não obtiveram uma gravidez. Dada a dificuldade de obter respostas reais nos questionários dos voluntários e a pequena dimensão da amostra para avaliar parâmetros com tanta variação inter-individual, o estudo não conseguiu obter resultados estatísticamente significativos na correlação do impacto de factores do estilo de vida no potencial reprodutivo. O estudo permitiu concluir que o nível de caspase-3 clivada nas células do cumulus parece ser um bom marcador da qualidade ovocitária e um bom predictor do resultado de gravidez.
Worldwide it is estimated that approximately 70 million couples suffer from infertility, which corresponds to one in each seven couples at fertility age. The rapid increase in reproductive problems in recent decades suggests that they are more likely to be caused by lifestyle and/or environmental factors than as a result of genetic variations. In Portugal 2.2% of the babies born result from an assisted reproduction technology (ART) technique. The multiple embryo transfer performed sometimes in ART techniques may result in multiple pregnancies, which have well known complications for mothers and babies. New diagnostic tools are needed to improve embryo selection, in order to transfer less embryos to achieve similar or better results. In this study the impact of lifestyle factors on the reproductive potential of 47 couples who resort to ART was investigated. Also, the correlation between the expression levels of an apoptotic marker (cleaved caspase-3) in oocytes cumulus cells and the achievement of pregnancy was performed (n=30). Significant (p<0.01) higher concentration of cleaved caspase-3 was observed in cumulus cells of couples who did not achieve pregnancy. Given the difficulty in obtain reliable answers from the volunteers in the questionnaires and the small sample size to evaluate parameters with such a wide inter-subject variability it failed to give conclusive statistical significant data in the lifestyle impact into reproductive potential. The present study allowed concluding that the level of cleaved caspase 3 in cumulus cells appears to be a good marker of oocytes quality and predictor of pregnancy outcome.
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Mackay, Martha. "The development of fluorescent probes targeting Caspase-3 for detecting apoptosis." Thesis, University of Edinburgh, 2014. http://hdl.handle.net/1842/17972.

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The design and development of fluorescent reporters focussed on highly sensitive, specific, and selective imaging of cancer targets is described. These novel optical molecular probes were synthesised with the aim of creating bio-imaging breakthroughs that will aid the clinical analysis of cancer. A specific target of the project was to develop fluorescent reporters for Caspases; intracellular endopeptidases that play an essential role in apoptosis. Lack of activation of the ‘Caspase Cascade’ causes uncontrolled proliferation of cells and has been deemed a ‘Hallmark of Cancer’. In particular, low Caspases-3/7 activities have been associated with a range of cancers, thus molecular detection of Caspases-3/7 activities could therefore lead to advances in oncology. A 14-member FRET library, based upon Caspases-3/7 specific peptide sequences, was initially developed. The cleavage rates and KM values were evaluated for Caspases-3/7, along with the cleavage rates for Cathepsin B, to determine the peptide with the greatest affinity and specificity for Caspase-3. Also developed was a set of internally quenched activity based molecular reporters constructed by attaching fluorophores to a tribranched dendron through the Caspase specific peptide, developed from the FRET Library. The KM values of the dendron probes with Caspase-3 were also evaluated. Furthermore, the dendron reporters were attached to cell penetrating peptides to enable delivery to intracellular Caspase and allow in situ detection of activated Caspase-3 within live cells. In addition, a new labelling moiety was developed enabling dual detection of reporters through fluorescence and MRI imaging. To achieve this, a perfluoro tag (C8F17) was tethered to a Cy5 dye to enable dual detection. The dual 19F-MRI/Cy5 dye was conjugated onto to a cell penetrating peptide to enable in vivo detection of the probe by 19F-MRI and fluorescent imaging.
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Pontin, Mariana Caroline Furian. "Proteção antioxidante do colostro bovino em células intestinais de juvenis de pacu (Piaractus mesopotamicus) submetidos a estresse." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-14082018-102616/.

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O estresse causa modificações no epitélio intestinal, tais como o aumento de células caliciformes e da taxa de apoptose. O uso de alimentos nutracêuticos tem sido uma alternativa para amenizar essas modificações sobre o tecido epitelial. Desta forma, este trabalho teve como objetivo avaliar se a inclusão de colostro bovino, o qual é constituído de fatores antioxidantes, imunes e de crescimento, seria capaz de amenizar as consequências do estresse crônico sob o intestino. Para isso, juvenis de pacu (Piaractus mesopotamicus) adensados a 50 kg/m3 foram alimentados duas vezes ao dia até a saciedade com ração peletizada e semi-purificada sem (0%CBL) e com a inclusão de colostro bovino liofilizado em concentrações crescentes (10, 20 e 30%CBL), (n=4). Após 28 dias, foram coletados segmentos do intestino médio, S1 e S2, e reto. Os tecidos foram marcados com corantes histológicos para a quantificação de células caliciformes contendo mucinas neutras, ácidas (incluindo sialo e sulfomucinas) e ácidas-neutras. Também foram mensurados o volume (Vv) e a densidade da superfície (Sv) da mucosa, por análise estereológica, e a espessura da camada muscular. A razão do número de cada tipo e subtipo de célula caliciforme sobre o Vv e Sv foi calculada para estimar a densidade de células caliciformes, Dv e Ds, respectivamente. A taxa apoptótica foi analisada qualitativamente através da intensidade (alta, média e baixa) da imunomarcação da caspase-3 nas células epiteliais. As dietas não influenciaram os parâmetros zootécnicos analisados (P>0,05). No reto, os grupos que receberam 20 e 30%CBL apresentaram menor número de células caliciformes contendo sulfomucinas e menor Ds em relação a 0 e 10% (P=0,0148 e 0,0198, respectivamente). No RT, Dv total e Dv de células caliciformes contendo mucinas ácidas foi maior em 0 e 30%CBL em relação a 20%CBL (P=0,0155 e 0,225, respectivamente). No S1, 10 e 30%CBL apresentaram maior Dv em relação a 20%CBL (P=0,0540). A espessura da camada muscular, o Vv e a Sv não diferiram entre os tratamentos (P>0,05). No S2 e RT, a taxa de apoptose teve relação inversa à concentração de colostro bovino liofilizado adicionado na ração. Nos três segmentos, houve maior proporção de células caliciformes contendo mucinas ácidas do que neutras, sendo a maioria representada por sulfomucinas. Assim, a inclusão de colostro bovino liofilizado nas rações de juvenis de pacu adensados diminuiu a apoptose nos segmentos intestinais S2 e RT e também diminuiu o número de células caliciformes contendo sulfomucinas no RT, indicando que o colostro bovino liofilizado pode ser utilizado como alimento nutracêutico para pacus (Piaractus mesopotamicus) adensados, a fim de diminuir a taxa apoptótica e proteger o intestino contra enzimas bacterianas, uma das principais funções das sulfomucinas.
The stress causes changes in the intestinal epithelium, such as the increase in the number of goblet cells and on the rate of apoptosis. The use of nutraceutical foods has been an alternative to soften these modifications on the epithelial tissue. Thus, this study aimed to evaluate if the inclusion of bovine colostrum, which is composed of antioxidant, immune and growth factors, would be able to attenuate the consequences of chronic stress on the intestine. For this, pacu juveniles (Piaractus mesopotamicus), stocked at density of 50 kg/m3, were fed twice daily until satiety with pelleted and semi-purified diet without (0% LBC) and with the inclusion of lyophilized bovine colostrum in increasing concentrations (10, 20 and 30% LBC), (n = 4). After 28 days, segments of the middle gut, S1 and S2, and rectum (RT) were collected. The tissues were stained with histological dyes for the quantification of goblet cells containing neutral, acidic (including sialo and sulphomucins) and acid-neutral mucins. The volume (Vv) and surface density (Sv) of the mucosa were also measured by stereological analysis and the thickness of the muscular layer. The ratio between the number of each goblet cell type and subtype and the Vv or Sv was calculated to estimate the density of goblet cells, Dv and Ds, respectively. The apoptotic rate was analyzed qualitatively according to the intensity (high, medium and low) of caspase-3 immunostaining in epithelial cells. The diets did not influence the zootechnical parameters analyzed (P> 0.05). In the rectum, the groups that received 20 and 30% LBC presented lower number of goblet cells containing sulphomucins and lower Ds in relation to 0 and 10% (P = 0.0148 and 0.0198, respectively). In RT, total Dv and Dv of goblet cells containing acid mucins were higher in 0 and 30% LBC in relation to 20% LBC (P = 0.0155 and 0.225, respectively). In S1, 10 and 30% LBC presented higher Dv in relation to 20% LBC (P = 0.0540). Muscle layer thickness, Vv and Sv did not differ between treatments (P> 0.05). In S2 and RT, the rate of apoptosis was inversely related to the concentration of lyophilized bovine colostrum added in the diet. In the three segments, there was higher proportion of goblet cells containing acidic than neutral mucins, most of them being sulphomucins. Thus, the inclusion of lyophilized bovine colostrum in diets of pacu juveniles reduced apoptosis in the intestinal segments S2 and RT and also decreased the number of goblet-containing sulphomucins in the RT, indicating that lyophilized bovine colostrum can be used as a nutraceutical feed for pacus (Piaractus mesopotamicus) under high stocking density to decrease the apoptotic rate and protect the intestine against bacterial enzymes, one of the main functions of sulphomucins.
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Chiang, Michelle. "Cardamonin induces apoptosis in human nasopharyngeal carcinoma cells via mitochondrial death pathway mediated by caspase-3 and caspase-8 activation, independent of caspase-9 signalling responses." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/32565/.

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Nasopharyngeal cancer lies in the upper part of throat behind the nose and near the base of the skull called the nasopharynx. It is more commonly diagnosed in parts of Asia, particularly in the southern China. Five local edible plants from different families; namely curry leaf (Murraya koenigii), temu kunci (Boesenbergia rotunda), spring onion leaf (Allium cepa), mushroom bean (Phaseolus vulgaris) and bunga kantan (Phaeomeria imperialis) were macerated to obtain methanol, ethyl acetate and hexane crude extracts. Each crude extract was tested against nasopharyngeal carcinoma (HK-1) and normal nasopharyngeal epithelial (NP-69) cell lines. All crude extracts from temu kunci (Boesenbergia rotunda) were found to contain flavonoids, alkaloids and polyphenols. Both methanolic and hexane crude extracts were found to exhibit cytotoxic effects against HK-1 cells but non-toxic against NP-69 cell line. Of all the bioactive compounds previously extracted from B. Rotunda, we have selected four commercially available flavonoids and polyphenols to narrow down our search to one potential anticancer agent. These compounds were tested against HK-1 and NP-69 cell lines for cytotoxicity and it was found that cardamonin exhibits highest cytotoxic effect against HK-1 cells with IC50 of 22 μg/mL. Cardamonin, a naturally occurring chalcone from the rhizome of Boesenbergia rotunda (locally known as temu kunci) was found to induce apoptosis in human nasopharyngeal carcinoma (HK-1) cell line in vitro. It exhibits a significant cytotoxic effect against human nasopharyngeal carcinoma cell line without affecting normal immortalized nasopharyngeal epithelial cell line (NP-69) in MTT assay. Based on these results, HK-1 cell line was treated with IC50 22 μg/mL in time-dependent manner 24, 48 and 72 hrs to further investigate the mechanisms of apoptosis. Apoptotic cells induced by cardamonin were illustrated by change in cellular morphology, increase in G2/M phase population and DNA fragmentation. Furthermore, up-regulation of caspase-3 and caspase-8 activities substantiated the induction of apoptosis through caspase-dependent pathway. Cardamonin leads to a decrease in overproduction of reactive oxygen species (ROS), disruption in mitochondrial membrane potential and drop in intracellular ATP level in HK-1 cells. Present study also revealed up-regulation of pro-apoptotic protein, Bax and apoptotic signalling factor, cytochrome c resulting in down-regulation of anti-apoptotic protein, Bcl-2. There was no fold change in caspase-9 gene expression level suggesting that HK-1 cellular apoptosis occurred independent of caspase-9. Activation of caspase-3 was directly regulated by caspase-8 and does not require caspase-9. Current findings on the mode of actions of cardamonin suggested its potential application as an anticancer agent against nasopharyngeal carcinoma.
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16

Beiche, Alexandra [Verfasser]. "Expression von Caspasen in Kopf-Hals-Tumoren : immunhistochemischer Nachweis von Caspase 1, 2, 3 und Proliferationsmarker Ki67 / Alexandra Beiche." Ulm : Universität Ulm. Medizinische Fakultät, 2001. http://d-nb.info/1015949746/34.

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17

Dick, Sarah. "Caspase 3 Cleavage of Pax7 Inhibits Self-Renewal of Satellite Cells." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32233.

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Compensatory growth and regeneration of skeletal muscle is dependent on the resident stem cell population, termed satellite cells. Self-renewal and maintenance of the satellite cell niche is coordinated by the transcription factor Pax7, yet continued expression of this protein inhibits the myoblast differentiation program. As such, the reduction or removal of Pax7 may denote a key prerequisite for satellite cells to abandon self-renewal and acquire differentiation competence. Here, we identify caspase 3 cleavage inactivation of Pax7 as a crucial step for terminating the self-renewal process. Inhibition of caspase 3 results in elevated Pax7 protein and satellite cell self-renewal, while caspase activation leads to Pax7 cleavage and initiation of the myogenic differentiation program. We have also noted that casein kinase 2 (CK2) directed phosphorylation of Pax7 attenuates caspase directed cleavage. Together, these results demonstrate that satellite cell fate is dependent on opposing post-translational modifications of the Pax7 protein.
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18

Pericleous, Louisa Maria. "Production of a caspase 3 based immuno-fusion : towards targeted apoptosis." Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406211.

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19

Malavez, Yadira. "Mechanisms of Caspase-3 Regulation in the Execution of Cell Death." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1331142346.

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20

Isobe, Naoki. "Caspase-3 Expression in Human Gastric Carcinoma and Its Clinical Significancec." Kyoto University, 2004. http://hdl.handle.net/2433/147499.

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21

Coutinho, Ana Rita Sousa. "Presença da Caspase-3 ativa e das proteínas de reparo de lesões do DNA em embriões suínos ativados partenogeneticamente com alta ou baixa capacidade de desenvolvimento." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-12122007-100619/.

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Apoptose é uma forma de morte celular extremamente conservada que tem papel primordial no desenvolvimento animal e na homeostasia celular, agindo como mecanismo de controle de qualidade com a função de remover células danificadas, em excesso ou não-funcionais. Este processo tem papel importante no desenvolvimento embrionário pré-implantacional, pois as células embrionárias estão sujeitas aos danos no DNA que podem ativar mecanismos de reparo de DNA ou induzir apoptose, que culmina com a ativação da enzima caspase-3 responsável pela clivagem de vários substratos celulares. Deste modo, o presente trabalho teve como objetivos determinar a presença da Caspase-3 ativa (+casp-3) e sua influência no desenvolvimento de embriões suínos no estágio de pré-implantação, bem como investigar a detecção de proteínas que atuam no mecanismo de lesão e reparo do DNA. Foram realizados 4 experimentos com oócitos imaturos de fêmeas pré-púberes, obtidos de ovários oriundos de abatedouro, maturados in vitro (MIV) por 44-46 horas. Oócitos em metáfase II (MII) foram ativados partenogeneticamente (AP) com ionomicina e cloreto de estrôncio e cultivados in vitro em PZM3 a 38ºC e 5% CO2 em ar e alta umidade. No primeiro experimento os embriões foram classificados em 4 grupos de acordo com o tempo de clivagem e o número de células: R4 - clivado às 24 horas e com ≥4 células às 48 horas; R2 - clivado às 24 horas e com 2 ou 3 células às 48 horas; L4 - não clivado às 24 horas e com ≥4 células às 48 horas; L2 - não clivado às 24 horas e com 2 ou 3 células às 48 horas. Os embriões foram então avaliados no D-6 do CIV para determinação do índice de desenvolvimento até o estágio de blastocisto. Os embriões do grupo R apresentaram maiores índices de blastocisto, R4 - 66,1 (174/263) e R2 - 59,6 (62/104) e maior número de núcleos por blastocisto, R4 - 40,1 e R2 - 37,8, quando comparados ao grupo L, L4 - 15,4 (6/39) e L2-16,8 (13/77); L4-18,5 e L2-18,3 (Qui-quadrado e Tukey-Kramer, respectivamente, P<0,05); entretanto, não houve diferença entre os grupos R4 e R2 e L4 e L2. Para o segundo experimento utilizou-se apenas embriões R e L, classificados às 24hs do início do CIV. Ambos os grupos (R e L) foram destinados à análise de imunocitoquímica para +casp-3 fixados nos D2, D4 e D6, sendo cada um destes dias considerado um sub-experimento e realizado em manipulações diferentes. Foi observada localização citoplasmática da +casp-3 do D2 ao D6 e nuclear a partir do D5 de cultivo. A quantificação relativa da +casp-3 nos grupos R e L de cultivo foi de 2,4 vs 1,4; 1,1 vs 1,0 e 1,1 vs 1,2 para o D2, D4 e D6, respectivamente. Para avaliar a influência da +casp-3 no desenvolvimento de embriões suínos foi realizado o terceiro experimento utilizando o inibidor de caspase z-DEVD-fmk (100uM) durante a MIV, no início (D0 ao D2) ou no final (D4 ao D6) do cultivo. Embriões produzidos sem inibidor foram usados como controle. A presença do inibidor durante a MIV e no final do cultivo não afetou os índices de blastocistos. No entanto, a presença do inibidor durante as primeiras 48 horas de cultivo resultou em maior índice de blastocisto do que o grupo controle, 55,1 (59/107) e 37,5 (39/104) (Qui-quadrado, P<0,05). O último experimento foi realizado para investigar a presença das proteínas de reparo de lesão de DNA, γH2AX, 53BP1, NSB1 e RAD52, em embriões desenvolvimento R e L. Não foi detectada 53BP1 em embriões suínos AP durante o desenvolvimento inicial. Embriões do grupo L apresentaram maior quantidade de γH2AX no D-5 quando comparado ao grupo R; entretanto, não houve diferença de marcação para NSB1 e RAD52. Estes dados indicam que o mecanismo de apoptose interfere no desenvolvimento embrionário inicial com efeito positivo do inibidor de caspase, na taxa de blastocisto de embriões suínos AP. Embriões de desenvolvimento L apresentaram um aumento da sinalização às injúrias do DNA, entretanto, a diferenças quanto ao potencial de reparo do DNA lesado em embriões de diferentes potenciais de desenvolvimentos, ainda precisam ser melhor investigadas.
Apoptosis is a highly conserved form of cell death that plays a major role in animal development and cellular homeostasis by acting as a quality control mechanism to remove cells that are damaged, nonfunctional, misplaced or supranumerary. This form of cell death plays a major role on preimplantation embryonic development since embryonic cells are often subject to DNA damage, triggering either DNA damage and repair mechanisms or apoptosis. Once initiated the apoptotic process leads to caspase activation and cleavage of cellular substrates. The aim of the present study was to quantify active Caspase-3 (+casp-3) and to determine the role of this pro-apoptotic enzyme on the development of preimplantation porcine embryos, as well as to investigate the presence and localization of DNA damage and repair proteins. Four experiments were conducted using slaughterhouse immature oocytes collected from pre-pubertal gilt ovaries and in vitro matured (IVM) for 44-46 h. Metaphase II (MII) oocytes were parthenogenetically activated (PA) using ionomycin and strontium chloride and cultured in PZM-3 at 38ºC, 5% CO2 in air and high humidity. In the first study embryos were distributed into 4 groups according to cleavage time and cell number: R4 - cleaved at 24 h with ≥4-cells at 48 h; R2 - cleaved at 24 h with 2-3 cells at 48 h; L4 - non-cleaved at 24 h with ≥4-cells at 48 h; L2 - non-cleaved at 24 h with 2-3 cells at 48 h. Group R embryos showed higher blastocyst rates R4-66.1 (174/263) and R2-59.6 (62/104) and more nuclei per blastocyst, R4-40.1 and R2-38.9, when compared to group L L4-15.4 (6/39) and L2-16.8 (13/77); L4-18.5 and L2-18.3 (Chi-square and Tukey-Kramer, P<0.05); however, there were no differences between R4 and R2 or L4 and L2. The second experiment used only early-(R) and late-cleaved embryos (L), classified at 24 h of IVC, fixed at D-2, D-4 and D-6 and then stained for +casp-3 immunofluorescence. In this embryos fixed at D-2, D-4 and D-6 were considered as sub-experiments conducted in different replicates. Active Caspase-3 cytoplasmic signal was detected in cultured embryos from D2 to D6 and nuclear signal was detected from D5 to D6. The relative amount of immunofluorescence signal for +casp-3 for groups R and L at D2, D4 and D6 of culture was 2.4 vs. 1.4; 1.1 vs. 1.0 and 1.1 vs. 1.2, respectively. A third experiment was conducted to evaluate the role of +casp-3 on porcine preimplantation embryos. In this study the Caspase inhibitor Z-DEVD-fmk (100 uM) was supplemented during maturation of porcine oocytes or embryo culture (D0 to D2 or D4 to D6). Addition of the caspase inhibitor during IVM or D4 to D6 of culture did not affect blastocyst rate. However, caspase inhibition from D0 to D2 increased development of porcine embryos to the blastocyst stage [55.1 (59/107) and 37.5 (39/104) for control and Z-DEVD-fmk, respectively; Chi-square, P<0.05). The last experiment investigated the presence of DNA damage and repair proteins γH2AX, 52BP1, NSB1, and Rad52 in early- and late-cleaved embryos by immunofluorescence. There was no 53BP1 signal in PA porcine embryos at beginning of IVC. Late-cleaved embryos showed higher γH2AX signal than early-cleaved embryos; however, there was no difference between NSB1 and Rad52 staining between these embryos. In conclusion, apoptosis and DNA damage and repair mechanisms play a role on development of porcine embryos. Active caspase-3 is present in porcine embryos throughout the preimplantation period and inhibition of this enzyme at early stages of in vitro culture can increase blastocyst rate of PA embryos. Moreover, late-cleaved embryos carry higher DNA damage than early-cleaved embryos. Therefore, the relationship between DNA repair mechanism and developmental potential of porcine embryos need to be further investigated.
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22

Sabbagh, Laurent. "Transcriptional regulation of the murine caspase-3 gene during T cell activation." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84320.

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Caspases play an important role in shaping the developing organism. They are required to eliminate unwanted or damaged cells and therefore are able to prevent disease. Several reports have shown increased caspase-3 expression in different cell types undergoing apoptosis. We undertook to examine the role of T cell activation through the T cell receptor (TCR) in regulating caspase-3 gene expression. The KOX-14 murine T cell hybridoma was initially used as a model for activation-induced cell death. Caspase-3 mRNA levels increased by 3-fold following T cell activation and was independent of STAT1 activation and therefore of IFN-gamma signaling in KOX-14 cells suggesting that the increase occurs early during T cell activation. Naive T cells were then isolated from the lymph nodes of mice to determine the extent of the increase in caspase-3 mRNA levels in cells undergoing proliferation rather than apoptosis. Caspase-3 mRNA levels were selectively induced (13-fold) following TCR triggering. Furthermore, caspase-3 mRNA levels were the highest in effector T cells which are destined to undergo AICD, when compared to long-lived memory T cells. Interestingly, the levels of procaspase-3 were also induced (6-fold) in activated peripheral T cells. In addition, T cells deficient for caspase-3 were more resistant to different apoptosis inducing molecules when compared to T cells containing normal levels of caspase-3. Altogether, these results demonstrate that the levels of caspase-3 must be maintained in a cell to ensure efficient apoptosis. The caspase-3 promoter region was subsequently cloned to identify transcription factors responsible for the observed increased in caspase-3 mRNA levels during T cell activation. Several regions within the promoter had either positive or negative regulatory effects on reporter activity when deleted. TCR stimulation of KOX-14 cells containing the different caspase-3 promoter constructs did not show changes in reporter ac
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23

Bushell, Martin. "The caspase-3 dependent coverage of eIF4G during the induction of apoptosis." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310249.

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24

Burns, Leanne E. "The Role of XRCC1 in the Repair of DNA Strand Breaks in Skeletal Muscle Differentiation." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20225.

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Caspase-3 has demonstrated a non-apoptotic function in several developmental programs including skeletal muscle differentiation, yet the mechanism of action has not been fully elucidated. Under apoptotic conditions Caspase-3 induces DNA fragmentation through activation of CAD. Recent observations have demonstrated CAD activity and the resulting DNA strand breaks are also vital for skeletal muscle differentiation. These breaks are transient in nature, suggesting an active DNA repair program to maintain genomic integrity. The aim of this study was to delineate the DNA repair mechanism coordinated with caspase/CAD mediated DNA damage. It was found that XRCC1 formed punctate nuclear foci early in myoblast differentiation concurrent to the induction of DNA damage. Caspase-3 inhibition caused attenuation of the formation of DNA lesions and XRCC1 foci in differentiating myoblasts. Targeted reduction in XRCC1 expression impaired myoblast differentiation. These results suggest that XRCC1 may play a role in repairing the DNA damage associated with myoblast differentiation.
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25

Lohmeier, Johannes [Verfasser], and Michael [Akademischer Betreuer] Meyer. "Calbindin-D28k and its role in apoptosis : inhibition of Caspase-3 activity and interaction with Pro-Caspase-3 investigated by in-situ FRET microscopy / Johannes Lohmeier ; Betreuer: Michael Meyer." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2018. http://d-nb.info/1163948667/34.

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26

Rodrigues, Bruna dos Santos. "Avaliação de toxicidade e potencial indutor de morte celular do 4-fluorbenzaldeidotiossemicarbazona contra células de adenocarcinoma de próstata PC-3." Universidade Federal de Goiás, 2013. http://repositorio.bc.ufg.br/tede/handle/tede/3726.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The death mechanisms induced by a new synthetic compound (4-FTC) in adenocarcinoma prostate cells (PC-3) and its toxicity were investigated in this study. PC-3 cells cytotoxity was evaluated by MTT reduction assay. The mechanisms involved in PC-3 death and cell cycle were investigated by flow cytometry and colorimetric assays. The compound toxicity was analized by cytotoxicity of mononuclear cells (MTT reduction assay) and 3T3 cells (neutral red uptake assay), myelotoxicity, haemolytic activity and acute oral toxicity. 4-FTC has concentration dependent cytotoxic activity in PC-3 cells, and 184,6 μM IC50. Investigation of death mechanisms indicated death by apoptosis, because of the significant increase in phosphatidylserine externalization (109,83%), loss of mytochondrial membrane potential (41,96%), significant increase of DNA fragmentation (284,02%) and capases 3/7 and 9 activity increase, 13,12% and 12,8%, respectively. Furthermore, the treatment of PC-3 cells wih 4-FTC did not induce the reactive oxygen species production, as well as, the induction of acid autophagic vesicles generation and did not change the cell cycle significantly. Althought 4-FTC was able to modulate the expression of some proteins that regulate cell cycle, incresead the expression of p53, p21 and p27. Thus, the results suggests that 4-FTC induced PC-3 death by apoptosis dependent by mitochondrial pathway activation. In toxicity evaluation, 4-FTC presented 52,86 μM and 19,63 μM IC50 to mononuclear and 3T3 cells, respectively; 27,35 μM IC50 to hematopoietic precursors; low acute oral toxicity, classified in GHS category 5, and not significant haemolytic activity.
Neste trabalho, investigaram-se os mecanismos de morte induzidos por um novo composto sintético, 4-fluorbenzaldeidotiossemicarbazona (4-FTC), nas células de adenocarcinoma prostático PC-3 e alguns parâmetros da toxicidade desse composto. A citotoxicidade nas células PC-3 foi avaliada pelo método de redução do MTT, método colorimétrico para avaliar a viabilidade celular. A investigação dos mecanismos de morte induzidos foi realizada por citometria de fluxo e ensaio colorimétrico. A toxicidade do composto foi avaliada pela citotoxicidade em células mononucleares pelo método de redução do MTT, citotoxicidade em células 3T3 pelo método de incorporação do vermelho neutro, mielotoxicidade, potencial hemolítico e toxicidade oral aguda. Os resultados obtidos mostram atividade citotóxica concentração dependente, com CI50 de 184,6 μM para PC-3. A investigação dos mecanismos de morte induzidos indicou morte por apoptose, pois houve aumento significativo da externalização da fosfatidilsserina (109,83%), perda do potencial de membrana mitocondrial em 41,96%, aumento significativo da fragmentação de DNA (284,02%) e aumento de caspases 3/7 e 9, em 13,12% e 12,8%, respectivamente. Além disso, não induziu a produção de espécies reativas de oxigênio, bem como, a formação de vesículas autofágicas ácidas e não alterou o perfil do ciclo celular de forma significativa. Embora tenha modulado a expressão de proteínas reguladoras do ciclo celular, aumentando a expressão de p53, p21 e p27. Assim, pode-se sugeririr que o 4-FTC induz morte por apoptose por meio de mecanismos de ativação dependentes da via mitocondrial em células PC-3. Na avaliação da toxicidade, o 4-FTC apresentou concentração inibitória 50% (CI50) de 52,86 μM e 19,63 μM para células mononuclerares e células 3T3, respectivamente; CI50 de 27,35 μM para precursores hematopoiéticos; baixa toxicidade oral aguda, sendo classificado na categoria 5 e baixo potencial hemolítico.
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27

Pelletier, Maude. "Controle des mecanismes d'activation de la caspase-3 (doctorat biologie cellulaire et biochimie)." Nantes, 2001. http://www.theses.fr/2001NANT16VS.

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28

Menapace, Ryan Mitchell. "Determination of the Effect of Cyclohexylmethylparaben on Activation of Apoptotic Caspase-3 in M624 Melanoma Cells." Marietta College Honors Theses / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=marhonors1588785389607076.

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29

Ruest, Louis-Bruno. "Peptide elongation factors and caspase-3 in myocytes : a way to control apoptosis." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38269.

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Few weeks after birth, a switch in peptide elongation factor 1As from EF-1alpha/EF1A-1 to S1/EF1A-2 occurs in brain neurons, heart and skeletal muscles of mammalians. In order to elucidate the reason behind this switch, I studied the expression of both homologous proteins during muscle differentiation and apoptosis and, documented the relation between peptide elongation factors and caspase-3 activation. I found that during in vitro muscle differentiation of L6 myoblasts, a switch in peptide elongation factors 1A occurs as physiologically observed in skeletal muscles. While EF-1alpha/EF1A-1 is expressed in replicating myoblasts, S1/EF1A-2 is solely found in differentiated myotubes where it replaces EF-1alpha/EFIA-1 as the major elongation factor. Similarly, upon serum deprivation-induced apoptosis, a reversion in peptide elongation factors 1A is observed: EF-1alpha/EF1A-1 replaces S1/EF1A-2 and becomes the major form of elongation factor 1A present in dying myotubes. This switch correlates in myotubes with the activation of caspase-3 protein, a cysteine protease involved in apoptosis. When L6 myotubes constitutively express S1/EF1A-2 as caused by adenoviral gene transfer, they become resistant to serum deprivation-induced apoptosis. In contrast, when L6 myotubes are transfected with EF-1alpha/EF1A-1 gene, they die more rapidly from serum deprivation-induced apoptosis than control cells. Transfection using anti-sense EF-1alpha/EF1A-1 gene protects myotubes from apoptotic cell death. Thus, both elongation factor 1As exert opposing effect on muscle survival: while EF-1alpha/EF1A-1 accelerates apoptotic cell death, S1/EF1A-2 protects muscles against apoptosis.
I found that skeletal muscles are the only tissues where, despite the constitutive expression of caspase-3 mRNA, the protein can be absent. Furthermore, I found that while immediately after birth, caspase-3 protein is present in skeletal muscles, a few weeks afterwards, the protein cannot be detected by Western blotting. In skeletal muscle, this change correlates with the observed switch in peptide elongation factors from EF-1alpha/EF1A-1 to S1/EF1A-2 and suggests that caspase-3 is translationally regulated in skeletal muscles. The laboratory previously reported that while EF-1alpha/EF1A-1 protein reappears; S1/EF1A-2 protein becomes absent from regenerating muscles. However, once tissue regeneration is completed, the situation returns to normal as EF-1alpha/EF1A-1 disappears and S1/EF1A-2 reappears to become the only type 1A elongation factor expressed in muscle.
In conclusion, I found that the developmental switch observed in peptide elongation factors from EF-1alpha/EF1A-1 to S1/EF1A-2 partly serves to protect muscle cells from apoptosis. Thus, I am the first to identify a noncanonical function for S1/EF1A-2. (Abstract shortened by UMI.)
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30

Szkoda, Blake E. "THE EFFECTS OF CITRAL ON CASPASE-3 ACTIVATION IN M624 AND HaCaT CELLS." Marietta College Honors Theses / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=marhonors1463566418.

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31

Ricardo, Ana Luísa de Oliveira Garcia. "Expressão da Caspase-3 activada no epitélio germinal de pacientes com azoospermia obstrutiva." Master's thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/715.

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Mestrado em Ensino de Geologia e Biologia
Sabe-se que na espermatogénese humana a apoptose é um mecanismo muito importante na regulação do equilíbrio entre as células de suporte (células de Sertoli) e as células germinativas ao longo do desenvolvimento, existindo também vários trabalhos que indicam um aumento das taxas de apoptose em situações de patologia testicular, como a privação hormonal, a rádioquimioterapia, as lesões obstrutivas (infecções, ausência congénita de canais excretores) e as lesões primárias do epitélio germinal (azoospermia secretora). Destes estudos, porém, nenhum utilizou métodos matematicamente correctos, pelo que os valores são muitas vezes contraditórios. Para resolver essa situação avaliamos por métodos estereológicos a presença de caspase-3 activa em biópsias testiculares de pacientes com espermatogénese conservada (controlos) e com azoospermia obstrutiva (casos). Os resultados demonstram que não existe um aumento global das taxas de apoptose na azoospermia obstrutiva. Na análise por tipo celular, os dados revelaram que na azoospermia obstrutiva as células de Sertoli e as células germinais diplóides são mais atingidas. Especificamente, as células de Sertoli apresentaram taxas superiores de apoptose do que qualquer tipo de célula germinativa, seguidas das espermatogónias, dos espermatócitos primários e dos espermatídeos redondos. Em conclusão, comparamos pela primeira vez, de modo quantitativo rigoroso por métodos estereológicos, as taxas de apoptose no epitélio germinal humano masculino na situação de azoospermia obstrutiva. Em relação aos controlos, os pacientes com azoospermia obstrutiva apresentam um maior atingimento das células germinais diplóides, sobretudo à custa dos espermatócitos primários. ABSTRACT: It is known that apoptosis in human spermatogenesis is a very important mechanism for the regulation of the balance between the support cells (Sertoli cells) and germ cells throughout development. It is quoted in numerous articles that there is a rise in the rates of apoptosis in the presence of testicular pathology, as observed in hormonal deprivation, radio-chemotherapy, obstructive lesions (infections, congenital absence of excretory channels) and primary injuries of the germinal cell layer (secretory azoospermia). However, the reported studies have not used accurate mathematical methods, and so the results are many times contradictory. To solve this situation we used stereological methods to ascertain for the presence of active caspase-3 in testicular biopsies of patients with conserved spermatogenesis (controls) and obstructive azoospermia (cases). Data shows that overall apoptosis in obstructive azoospermia is not increased. Per cell type analysis results indicate that in obstructive azoospermia both Sertoli and diploid germ Cells are by fare more involved. Specifically, Sertoli cells show a higher degree of apoptosis than any other germ cell type, followed by spermatogonia, primary spermatocytes and round spermatids. In conclusion, we compared for the first time, with precise quantitative stereological methods the apoptosis rate in the human male germ cell layer with obstructive azoospermia. When compared to controls, cases with obstructive azoospermia show higher rates of diploid germ cell injury, essentially due to involvement of primary spermatocytes.
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32

Kiziler, Fahri. "Wirkung von Dinukleosidpolyphosphaten und Elektrolyten auf die Caspase-3-Aktivität bei Niereninsuffizienz und Sepsis." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=96560943X.

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33

Calderón, Celmira [UNESP]. "Imunomarcação de COX-2, PGE-2, VEGF e CASPASE-3 em mastocitomas cutâneos caninos." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104672.

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Universidade Estadual Paulista (UNESP)
O mastocitoma canino (MCT) é uma neoplasia maligna de grande importância na clínica oncológica devido ao seu comportamento biológico agressivo e alta freqüência. A COX-2 e a PGE2 têm sido associadas à promoção e progressão tumoral e seus principais mecanismos envolvem estímulos da angiogênese tumoral e a inibição da morte celular programada. O VEGF é um potente indutor da angiogênese e a caspase-3 tem um importante papel na via efetora da apoptose. Compreender o mecanismo pela qual a COX-2 pode estimular a progressão tumoral no mastocitoma, permite ampliar o conhecimento do comportamento biológico desta neoplasia e direcionar tratamentos mais eficazes. O presente trabalho fez um estudo retrospectivo em 24 casos de mastocitoma canino (MCT). As neoplasias foram classificadas de acordo com Patnaik et al. (1984) e a expressão da COX-2, PGE2, VEGF e caspase-3 foram avaliadas usando a técnica de imunoistoquímica. A expressão da COX-2 foi correlacionada à expressão do VEGF, PGE2 e caspase-3 nos diferentes graus histopatológicos. A imunomarcação da caspase-3 foi menor nos tumores indiferenciados comparados com os bem diferenciados. Comparando os dados da expressão da COX-2 com os demais marcadores foi observado a correlação positiva entre COX-2 e PGE2, COX-2 e VEGF nas graduações II e III. A correlação entre COX-2 e caspase-3 foi somente detectada no grau III.
The canine mast cell tumor (MCT) is a malignant neoplasia with great importance on the clinical practice due to its aggressive behavior and high frequency. The COX-2 and the PGE2 have been associated to the tumor initiation, promotion and progression, and its main mechanisms involve the stimuli of tumor angiogenesis and the inhibition of apoptosis. The VEGF is a powerful inductor of angiogenesis and the caspase-3 is responsible for most part of the apoptotic effects. The understanding of the mechanism by which the COX-2 stimulates the tumor progression in the mast tumor cells provides an extension through the biological behavior of this neoplasia and leads to a better and effective treatment. The present work was a retrospective study in 24 cases of MCT. The neoplasias were classified according to Patnaik et al. (1984) and the expression of COX-2, PGE2, VEGF and caspase-3 were evaluated using the immunohistochemistry technique. The expression of COX-2 was correlated to the expression of VEGF, PGE2 and caspase-3 in the different histopathologic grades. Caspase-3 immunolabeling was lower in the undifferentiated tumors compared to the more differentiated ones. Comparing the COX-2 expression data to the other markers it was observed a positive correlation between COX-2 and PGE2, COX-2 and VEGF in grade II and III. Correlation between COX-2 and caspase-3 was detected only on grade III. Keywords: COX-2, PGE2, VEGF, caspase-3, mast cell tumor.
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34

Liu, Rui. "Development of novel peptides for blocking aggregation and caspase-3 cleavage of TDP-43." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/33548.

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TAR DNA-binding protein 43 (TDP-43) is a protein that is thought to be involved the pathology of amyotrophic lateral sclerosis (ALS) and frototemporal lobar degeneration (FTLD). Several TDP-43 mutations have been found in sporadic and familial ALS and FTLD. In patients with these neurodegenerative diseases, TDP-43 forms insoluble inclusions in the nucleus and cytoplasm of neurons. Evidence shows that TDP-43 is abnormally cleaved by caspase-3 and that the truncated inclusions were toxic to cells, which may be the cause of neurodegenerative diseases. To explore novel treatments of neurodegenerative diseases, we identified regions in TDP-43 that are bound by TDP-43 itself or by caspase-3 using high density peptide array analysis. Based on the identification of the key regions, peptides that might be able to block the interactions were designed. We found our synthetic peptides could effectively inhibit the formation of TDP-43 protein aggregations in a concentration-dependent manner in Hela cells in which a mutated human TDP-43 gene was overexpressed. However, these peptides could not prevent cell death. These results suggest that TDP-43 aggregation is a consequence of the cell death process rather than a cause. In addition, the synthetic peptides that are able to block the binding of caspase-3 to TDP-43 in a cell-free assay were also effective in inhibiting the cleavage of TDP-43 in cultured neuronal cells after NMDA insults. Furthermore, application of our peptide was able to block NMDA-induced, caspase-3 dependent cell death. These results suggest new approaches to treatment of ALS and FTLD.
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35

Tavari, Mohsen. "Hybrid molecules as inhibitors of the monoamine oxidases and caspase 3 for neurodegenerative disorders." University of the Western Cape, 2016. http://hdl.handle.net/11394/5069.

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Magister Pharmaceuticae - MPharm
Neurodegenerative diseases are multifactorial in nature, and taking the complex nature of these disorders into consideration, multi-target directed ligands may present as better options to treat these disorders than the classic ‘one molecule, one target’ approach. Neurotransmitter amines are catabolized by monoamine oxidase A and B (MAO-A and MAO-B), therefore they have been targeted for the treatment of neuropsychiatric and neurodegenerative diseases. Besides offering a potential antidepressant action in PD, MAO-A inhibitors may also provide a symptomatic benefit by reducing MAO-A-catalysed oxidation of dopamine. The oxidative deamination reaction catalyzed by MAO-B is one of the major catabolic pathways of dopamine in the brain. Inhibition of this enzyme leads to enhanced dopaminergic neurotransmission and are currently used in the symptomatic treatment of PD. Furthermore, MAO-B inhibitors may also exert neuroprotective effects by reducing the concentration of potentially hazardous by-products produced by MAO-B-catalysed dopamine oxidation. Apoptosis or programmed cell death occurs in a number of neurodegenerative disorders and it has been proven that inhibition of the executing enzyme, caspases-3, slows down or even stops apoptosis. Having this in mind we focused on the propargylamine function of selegiline and the fluorophenyl function of safinamide, because of their inherent monoamine oxidase inhibitory activities; and isatin as a non-peptide inhibitor of caspase-3. Therefore we attempted to design and synthesize multifunctional hybrid molecules acting simultaneously to halt the apoptotic neuronal breakdown process and eliminate the signs and symptoms of diseases such as PD. Seven novel compounds were successfully synthesized utilizing multistep processes. The synthesis of 5 chlorosulfonyl isatin was accomplished starting from the commercially available isatin in two steps, which were, sulfonation using tetramethylene sulfone and chlorination with POCl₃. Next 5-chlorosulfonyl isatin was conjugated to the fluorophenylamine derivative with the fluoro-function at either the ortho, meta or para position through a nucleophilic substitution reaction on the chlorosulfonyl position. The resultant compounds were coupled on the N position of the isatin function with propargyl bromide, using a microwave synthesis procedure, in a nucleophilic substitution reaction. The structures and purity were confirmed by nuclear magnetic resonance (NMR) and mass spectrometry (MS). In the biological evaluations recombinant human MAO-A, MAO-B and caspase 3 enzymatic assays were performed to determine the activity of the novel compounds at an enzymatic level. The inhibition percentages for these compounds were calculated and plotted against the logarithm 8 of the inhibitor concentrations to obtain a sigmoidal dose-response curve and consequently the IC50 value. The synthesized compounds showed inhibition of the MAO-A, MAO-B and caspase-3 enzymes at low to high micro molar concentrations. The role of the fluorophenylamine moiety in the synthesized compounds was significant for their multifunctional activity as shown by compounds 3 and 4 having good inhibitory activity towards MAO-A, MAO-B and also excellent inhibitory activity against caspase 3, making those ideal candidates for further lead compound development and multifunctional drug design. The introduction of the propargylamine moiety only increased the MAO-A inhibitory activity; this was shown by compounds 7, 8 and 9 which exhibit good MAO-A selectivity with low MAO-B and caspase-3 inhibitory activities.
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36

Takata, Tetsuya. "Clinical Significance of Caspase-3 Expression in Pathologic-Stage I, Nonsmall-Cell Lung Cancer." Kyoto University, 2003. http://hdl.handle.net/2433/148759.

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37

Calderón, Celmira. "Imunomarcação de COX-2, PGE-2, VEGF e CASPASE-3 em mastocitomas cutâneos caninos /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/104672.

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Orientador: Renée Laufer Amorim
Banca: Noeme Sousa Rocha
Banca: Luiz Henrique de Araújo Machado
Banca: Mirela Tinucci. Costa
Banca: Sara Maria Carvalho e Suzano
Resumo: O mastocitoma canino (MCT) é uma neoplasia maligna de grande importância na clínica oncológica devido ao seu comportamento biológico agressivo e alta freqüência. A COX-2 e a PGE2 têm sido associadas à promoção e progressão tumoral e seus principais mecanismos envolvem estímulos da angiogênese tumoral e a inibição da morte celular programada. O VEGF é um potente indutor da angiogênese e a caspase-3 tem um importante papel na via efetora da apoptose. Compreender o mecanismo pela qual a COX-2 pode estimular a progressão tumoral no mastocitoma, permite ampliar o conhecimento do comportamento biológico desta neoplasia e direcionar tratamentos mais eficazes. O presente trabalho fez um estudo retrospectivo em 24 casos de mastocitoma canino (MCT). As neoplasias foram classificadas de acordo com Patnaik et al. (1984) e a expressão da COX-2, PGE2, VEGF e caspase-3 foram avaliadas usando a técnica de imunoistoquímica. A expressão da COX-2 foi correlacionada à expressão do VEGF, PGE2 e caspase-3 nos diferentes graus histopatológicos. A imunomarcação da caspase-3 foi menor nos tumores indiferenciados comparados com os bem diferenciados. Comparando os dados da expressão da COX-2 com os demais marcadores foi observado a correlação positiva entre COX-2 e PGE2, COX-2 e VEGF nas graduações II e III. A correlação entre COX-2 e caspase-3 foi somente detectada no grau III.
Abstract: The canine mast cell tumor (MCT) is a malignant neoplasia with great importance on the clinical practice due to its aggressive behavior and high frequency. The COX-2 and the PGE2 have been associated to the tumor initiation, promotion and progression, and its main mechanisms involve the stimuli of tumor angiogenesis and the inhibition of apoptosis. The VEGF is a powerful inductor of angiogenesis and the caspase-3 is responsible for most part of the apoptotic effects. The understanding of the mechanism by which the COX-2 stimulates the tumor progression in the mast tumor cells provides an extension through the biological behavior of this neoplasia and leads to a better and effective treatment. The present work was a retrospective study in 24 cases of MCT. The neoplasias were classified according to Patnaik et al. (1984) and the expression of COX-2, PGE2, VEGF and caspase-3 were evaluated using the immunohistochemistry technique. The expression of COX-2 was correlated to the expression of VEGF, PGE2 and caspase-3 in the different histopathologic grades. Caspase-3 immunolabeling was lower in the undifferentiated tumors compared to the more differentiated ones. Comparing the COX-2 expression data to the other markers it was observed a positive correlation between COX-2 and PGE2, COX-2 and VEGF in grade II and III. Correlation between COX-2 and caspase-3 was detected only on grade III. Keywords: COX-2, PGE2, VEGF, caspase-3, mast cell tumor.
Doutor
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38

Rodrigues, Luciana Villela. "Caspase 3, Caspase 8, Bax e Bcl2 em polpas de dentes decíduos humanos com reabsorção radicular fisiológica avaliadas por PCR em tempo real e imunoistoquímica." Universidade Federal de Minas Gerais, 2012. http://hdl.handle.net/1843/BUBD-92MNZS.

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Physiological root resorption is a programmed event that takes place in primary teeth leading to elimination of all root structures. Through this phenomenon the primary teeth lose support at oral cavity given place to the permanent dentition. The mechanism behind pulp elimination indicates apoptosis but its pathway has not been well characterized yet. To better understand this event, we evaluated the gene expression of bax, bcl-2, caspases 3 and 8 through real-time polymerase chain reaction (PCR) and morphometrically the protein expression of Caspase 8, Caspase 3, Bcl-2 and Bax in primary pulps by immunohistochemistry reaction. Samples were split into two groups: pulps from primary teeth with physiological root resorption (n=40) and control (n=40), pulps from permanent teeth. Samples of each group were split into PCR (n=20) and immunohistochemistry (n=20). PCR results showed a higher caspase 3 mRNA level in primary teeth than in pulps from permanent teeth. The expression of bax gene was more intense than caspase 8 but both did not show difference between groups. The bcl2 mRNA level was incipient and similar between groups. Pulps from primary teeth showed a high Caspase 3 and Bax immunoexpression. Immunolabeling to Caspase 8 was less intense, which implies that extrinsic via is not likely to be involved. Compared to Bax expression, immunolabeling to Bcl2 was incipient. These results were similar but less intense in pulps of permanent teeth. In conclusion, immunolabeling to Caspase 3 and Bax associated with a higher expression of these genes in pulps of primary teeth indicate that mitochondrial pathway apoptosis play a role in pulpar elimination during physiological root resorption.
A reabsorção radicular fisiológica é um evento programado que acomete dentes decíduos humanos. Trata-se da eliminação fisiológica das raízes deste grupo dentário o qual perde sustentação na cavidade bucal dando lugar à dentição permanente. A apoptose é indicada como responsável pela eliminação pulpar, porém as vias apoptóticas envolvidas ainda não foram descritas. Para melhor entender este evento foram quantificados os níveis de mRNA dos genes bax, bcl-2, caspases 3 e 8 através da reação em cadeia da polimerase em tempo real (PCR) e a expressão das proteínas Bax, Bcl2, Caspase 3 e 8, por meio de reações imunoistoquímicas em amostras pulpares. As amostras foram divididas em dois grupos: um grupo de polpas de dentes decíduos humanos (n=40), com reabsorção radicular fisiológica e um grupo controle (n=40), formado por amostras pulpares de terceiros molares superiores. Destas, 20 amostras de cada grupo foram submetidas ao PCR e o restante às reações imunoistoquímicas. Resultados da PCR em tempo real mostraram alta expressão de caspase 3 em polpas de dentes decíduos quando comparado com as de dentes permanentes, além de expressão mais intensa de bax do que de caspase 8 em ambos os grupos, porém sem diferença significante entre eles. A expressão de bcl2 foi incipiente e similar entre os grupos. Verificou-se ampla marcação imunohistoquímica para Caspase 3 e Bax nas amostras pulpares de dentes decíduos com menor expressão de Caspase 8. Estes resultados se repetiram de maneira discreta nas amostras pulpares de dentes permanentes. Não houve marcação com o anticorpo anti-Bcl2 em ambos os grupos. Considerando a mais ampla marcação imunoistoquímica de Caspases 3 e Bax, a maior expressão gênica de caspase 3 e de bax do que caspase 8 em polpas de dentes decíduos pode-se concluir que a apoptose, importante mecanismo de eliminação pulpar durante a reabsorção radicular fisiológica de dentes decíduos humanos, ocorre através da ativação de Caspase 3 pela via mitocondrial.
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39

Champagne, Julien. "Etude du rôle de la cycline D1 dans la survie cellulaire." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTT018.

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Chez la femme, le cancer du sein est le cancer le plus fréquemment diagnostiqué. Différents traitements sont disponibles selon le sous-type tumoral. Cependant, certaines patientes sont réfractaires à ces thérapies et restent vulnérables lors de récidives. Le cancer a longtemps été défini par une division aberrante des cellules, mais aujourd'hui, il est évident que la résistance à la mort cellulaire programmée est un paramètre majeur dans l'étiologie de la maladie.Les cyclines de type D régulent le cycle cellulaire en permettant la transition de la phase G1 à la phase S. Pour cela, elles activent les kinases dépendantes des cyclines 4/6 (CDK4/6) qui phosphorylent les protéines du rétinoblastome ce qui libère le facteur de transcription E2F. La Cycline D1 (CycD1) nucléaire est donc centrale dans le contrôle du cycle. Son gène est amplifié dans les cancers humains et la moitié des patientes atteintes d'un cancer du sein ont une surexpression de CycD1. Par l’activation de CDK4, CycD1 est essentielle à l'apparition et à la progression tumorale. Ainsi, des inhibiteurs spécifiques de CDK4/6 ont été développés contre le cancer du sein. Malheureusement, certaines patientes restent insensibles à ce traitement. À ce titre, le ciblage spécifique de CycD1 pourrait représenter une alternative clinique. En effet, en plus de la régulation du cycle, CycD1 est également impliquée, indépendamment de CDK4, dans la survie des cellules cancéreuses. Cependant, aucun mécanisme de l'impact de CycD1 dans le maintien tumoral n'a été établi pour démontrer ce potentiel thérapeutique. En outre, CycD1 a été décrite dans les organes à l’âge adulte pour réguler le métabolisme du glucose et l'hématopoïèse. Par conséquent, pour éviter tout effet secondaire indésirable, nous avons décidé d’évaluer l’implication potentielle de CycD1 dans les organes adultes. Grâce au Tandem-HTRF, basé sur le transfert d'énergie entre deux anticorps, nous avons révélé la dynamique inattendue de CycD1 dans chaque organe adulte. De plus, nous avons montré que l’altération de l'expression de CycD1 conduit à une diminution des capacités de survie des cellules saines post-mitotiques.Au vu de ces limitations, nous avons développé une nouvelle approche d'ARN interférence spécifique des cellules cancéreuses appelée TAG-RNAi. Cette technologie permet de cibler CycD1 uniquement dans la tumeur afin d'épargner les cellules saines. Cette approche innovante consiste à cibler un tag présent uniquement sur l’ARNm de CycD1 des cellules cancéreuses. Ainsi, nous avons découvert que le ciblage spécifique de CycD1 induit une régression rapide et spontanée des tumeurs dépendantes des oncogènes RAS ou ERBB2. Par protéomique in vivo, j'ai découvert que lors de stress pro-apoptotiques, CycD1 cytoplasmique interagit avec la procaspase-3 et bloque son activation pour empêcher l'apoptose des cellules. Ces travaux démontrent la valeur clinique du ciblage spécifique de CycD1 dans les cancers afin d'améliorer l'efficacité des chimiothérapies.Par conséquent, il restait à déterminer comment appliquer le TAG-RNAi contre CycD1 uniquement dans les cellules cancéreuses des patientes. Puisque le tag exotique présent sur le gène Ccnd1 chez la souris nous a permis de cibler spécifiquement les cellules cancéreuses, nous avons pensé que des mutations retrouvées dans les cancers humains représentaient une option de ciblage. Ainsi, nous avons étendu le concept TAG-RNAi aux mutations somatiques caractéristiques des cancers pour cibler avec succès l'expression des mutants KRAS-G12V ou BRAF-V600E comme exemples. L'idée est donc d'identifier les mutations de Ccnd1 chez les patientes afin d'appliquer le TAG-RNAi comme une thérapie personnalisée afin d’éviter les effets secondaires. Enfin, l'expression de CycD1 représente un nouveau biomarqueur pour le cancer et les troubles liés à l'âge: de faibles taux prédisposent aux maladies dégénératives tandis que des taux élevés indiquent une susceptibilité accrue au cancer
Breast cancer is the most frequently diagnosed cancer in women. This cancer is the leading cause of death in women aged from 35 to 65 years old. Different treatments are now available depending on tumor subtypes. However, some patients are still refractory to these therapies and are at risk of disease relapse. Cancer research has long focused on aberrant cancer cell division but today it is evident that the resistance to programmed cell death is also a major characteristic of the disease.D-type cyclins regulate cell cycle by allowing the transition from the G1-phase to the S-phase. These regulatory subunits activate the Cyclin-Dependent Kinases 4/6 (CDK4/6) that phosphorylate the retinoblastoma proteins which then release the E2F transcription factors. Nuclear Cyclin D1 (CycD1) is therefore central in the control of division. The Ccnd1 gene is amplified in human cancers and half of breast cancer patients bare an overexpression of CycD1. CycD1 is required for mammary carcinoma onset and progression in a CDK4 kinase-dependent manner. Hence, specific CDK4/6 inhibitors have been developed and authorized in the clinics against breast cancer. Unfortunately, some patients remain insensitive to this treatment. In this frame, the specific targeting of CycD1 could represent a strategic alternative in clinics to overcome these pitfalls. Indeed, in addition to cell cycle regulation with CDK4, CycD1 is also involved in CDK4-independent features of cancer cells like cell survival. However, to date, no clear mechanism for the impact of CycD1 in tumor maintenance is established to demonstrate the therapeutic value of its targeting.Moreover, recent studies have demonstrated the participation of CycD1 in adult organs to regulate glucose metabolism and hematopoiesis. As a consequence, to avoid any undesirable side effects, we decided to gauge the potential CycD1 implication in post-mitotic organs body-wide. We set up a new hypersensitive technology named Tandem-HTRF based on the energy transfer between two antibodies to reveal the unexpected dynamics of CycD1 expression in adult organ. Then, we discovered that alterations of CycD1 expression induced dramatic functional consequences on the survival capacities of healthy adult post-mitotic cells.Based on these limitations, we developed a novel RNAi approach specific to cancer cells named TAG-RNAi. This technology allows the silencing of CycD1 in cancer cells only to spare healthy cells. This innovative approach consists in the targeting of a mRNA tag only present on CycD1 from cancer cells. Using this technique, we found that the specific silencing of CycD1 induces a rapid and spontaneous regression of tumors driven by the RAS or ERBB2 oncogenes. Then, thanks to a proteomics screening in vivo, I discovered that under pro-apoptotic stresses the cytoplasmic CycD1 interacts with the procaspase-3 protein and blocks its activation to prevent cancer cell apoptosis. Altogether, my work demonstrates the clinical value of the specific targeting of CycD1 in cancers to increase the efficacy of chemotherapeutic treatments.Hence, it remained to be determined how to apply in patients RNAi against CycD1 only in cancer cells. Because the exotic tagging of its gene was instrumental in mice cancer models, we reasoned that human cancer mutations could represent such a specific tag. We have extended the concept of TAG-RNAi to somatic mutations characteristic of human cancers to successfully target the expression of KRAS-G12V or BRAF-V600E mutants as examples. The idea is therefore to identify Ccnd1 mutations in cancer patients in order to apply TAG-RNAi as a custom therapeutic approach that will manage side effects. More unanticipated, CycD1 expression represents a new biomarker for both cancer and age-related disorders: low CycD1 levels predispose to degenerative complications while high CycD1 levels indicate increased susceptibility to cancer and resistance to treatment
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40

Donoghue, Stephen. "Investigation of the expression and localisation of Caspase-3 in high grade Non-Hodgkin's Lymphoma." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/29355.

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Although B cell Diffuse Large Cell Lymphoma (DLCL) can respond with chemotherapy and radiotherapy, a large number of patients are still resistant to treatment. The caspase family of enzymes are crucial components of the apoptotic cell death process, and are believed to be important in the pathogenesis and treatment of lymphoid malignancies. It was hoped that the investigation of the expression and localisation of Caspase-3 in high grade Non-Hodgkin's Lymphoma (NHLs) would provide information with respect to the progression and treatment of DLCL. The pattern of proCaspase-3 expression was studied using immunohistochemistry with a commercial antibody in 54 cases of DLCL. The patterns of expression of the active p17 fragment of Caspase-3 was also examined using immunohistochemistry in both reactive lymph nodes and DLCL cases. Tumour cells displayed both a diffuse cytosolic and a punctate cytosolic staining for proCaspase-3 and survival curves indicated that tumour cells with a diffuse cytosolic expression of Caspase-3 correlated with a poor prognosis. In addition, a punctate expression was associated with complete response to treatment. Cases with a small percentage of lymphoma cells expressing Caspase-3 also tended to show poor survival. Levels of Caspase-3 mRNA were not significant, although a weak trend was observed similar to the immunohistochemical analysis. Furthermore, a survival curve indicated that a high TUNEL positivity was associated with a poor survival probability. In the reactive lymph node tissue the immunopositivity pattern of the p17 fragment of Caspase-3 mirrored that of the TUNEL staining in that apoptotic cells and the occasional tingeable body macrophage were staining.
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41

Lima, Bruno Roque [UNESP]. "Relação da ciclooxigenase-2 com VEGF e a caspase-3 nas neoplasias mamárias de cadelas." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/95529.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Nas cadelas, os tumores de mama representam em média 40% de todos os tumores, e sua carcinogênese é atribuída a interação complexa de fatores individuais da paciente. A enzima ciclooxigenase-2 (COX-2) apresenta-se como um marcador potencial para o câncer de mama, uma vez que é expressa em resposta a processos inflamatórios, que frequentemente acompanham as neoplasias e alterando o seu prognóstico. A caspase-3 é foco de estudos relacionados ao mecanismo da apoptose, tornando-se peça-chave no entendimento dos mecanismos de morte celular. O VEGF está envolvido na angiogênese e linfangiogênese, apresentando papel importante na progressão do câncer. O objetivo deste trabalho foi investigar a imunorreatividade da ciclooxigenase-2, do VEGF e da Caspase-3 nas neoplasias mamárias de cadelas, e correlacionar a expressão da COX-2 com o VEGF e com a Caspase-3, nesses tumores. Para a realização deste estudo foram selecionadas 60 amostras de tumores mamários de cadelas e 10 amostras de tecido mamário livre de malignidade que foram divididas em seis grupos compostos por 10 tumores de mesma classificação histológica cada grupo, e um grupo composto por 10 amostras de tecido mamário livre de malignidade. Os grupos foram denominados Adenomas, Carcinomas de prognóstico bom, Carcinomas de prognóstico ruim, Carcinomas primários metastáticos, Metástases pulmonares, Carcinomas inflamatórios e Controle. Os 7 grupos foram agrupados em micro-arranjo tecidual em lâmina de microscopia, e analisados através de imunoistoquímica pela técnica estreptavidina-biotina-peroxidase. A avaliação da intensidade de marcação foi obtida por densitometria com auxílio do programa ImageJ. A intensidade da marcação da Cox-2 foi maior nos casos de metástase pulmonar e fraca nos casos de...
In bitches, breast tumors represent an average of 40% from all tumors, and its carcinogenesis is attributed to a complex interaction of individual patient’s factors. The enzyme cyclooxygenase-2 (COX-2) is presented as a potential marker for breast cancer, since it is expressed in response to inflammation, which are often associated with neoplasms, changing its prognosis. Caspase-3 has been investigated as a key-protein associated with the mechanism of apoptosis, becoming a key part in understanding the mechanisms of cell death. VEGF is involved in angiogenesis and lymphangiogenesis, presenting important role in cancer progression. The objective of this study was to investigate the immunoreactivity of cyclooxygenase-2, VEGF and Caspase-3 in mammary neoplasms in bitches, and correlate the expression of COX-2 and VEGF and the Caspase-3 in these tumors. For this study we selected 60 samples of bitches´s mammary tumors and 10 samples of breast tissue malignancy´s free, which were divided into six groups of 10 tumors of the same histological grade of each group and one group of 10 breast tissue samples malignancy´s free. The groups were called adenomas, carcinomas good prognosis, carcinomas with poor prognosis, metastatic primary carcinomas, lung metastases, inflammatory carcinomas and Control. The seven groups were grouped into tissue micro-array on a microscope slide, and analyzed by immunohistochemistry technique streptavidin-biotin-peroxidase. The evaluation of the intensity of staining was obtained by densitometry using the program ImageJ. The intensity of COX-2 labeling was higher in cases of pulmonary metastasis and poor in cases of adenoma. In the assessment of marking of Caspase-3, there was a significant correlation between the control and carcinoma with poor prognosis (p <0.001) Furthermore, there was significant difference... (Complete abstract click electronic access below)
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42

Fang, Bin. "Structural Basis of Caspase-3 Substrate Specificity Revealed by Crystallography, Enzyme Kinetics, and Computational Modeling." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/biology_diss/69.

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Caspase-3 is a cysteine protease that hydrolyzes diverse intracellular proteins during programmed cell death (known as apoptosis). It has been a popular target for drug design against abnormal cell death for more than a decade. No approved caspase based drug, however, is available so far. Therefore, structural insights about the substrate recognition of caspase-3 are needed for the future development of caspase-3 based inhibitors and drugs. In this study, crystal structures of recombinant caspase-3 in complex with seven substrate analog inhibitors, including acetyl (Ac)-DEVD-aldehyde (Cho), Ac-DMQD-Cho, Ac-IEPD-Cho, Ac-YVAD-Cho, Ac-WEHD-Cho, Ac-VDVAD-Cho, and tert-butoxycarbonyl (Boc)-D-fluoromethylketone (Fmk), have been analyzed in combination with enzyme kinetic data and computational models. Seven crystal structures were determined at resolutions of 1.7-2.6Å. The binding conformation of each inhibitor residue at P1-P4 position was analyzed. The negative P1 aspartic acid side chain is exclusively required by the positive S1 pocket of caspase-3. Small hydrophobic P2 residues are preferred by the nonpolar S2 pocket formed by Y204, W206, and F256. Although hydrophilic residues at P3 position tend to fit better, hydrophobic residues also can be accommodated by the plastic S3 pocket. Two substrate binding sites were found in the S4 pocket, one formed by main chain atoms of F250 and side chain atoms of N208 and the other formed by aromatic side chains of W206 and W214. These two binding sites are responsible for the binding of hydrophilic and hydrophobic P4 residues, respectively. Furthermore, the S5 subsite of caspase-3 formed by side chains of F250 and F252 was discovered. It stabilizes hydrophobic P5 residues on the substrates by an induced fit mechanism. Computational studies were performed to help improve prediction of protein structures and protein-ligand interactions. Based on the Morse’s function, a novel potential function with only three adjustable parameters per residue pair was developed, which will significantly increase the efficiency of protein structure prediction and molecular mechanics. Altogether, our studies have provided valuable information for the future caspase-3 based drug development.
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43

Lima, Bruno Roque. "Relação da ciclooxigenase-2 com VEGF e a caspase-3 nas neoplasias mamárias de cadelas /." Jaboticabal, 2012. http://hdl.handle.net/11449/95529.

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Orientador: Carlos Roberto Daleck
Coorientador: Andrigo Barboza de Nardi
Banca: Mirela Tinucci Costa
Banca: Renée Laufer Amorim
Resumo: Nas cadelas, os tumores de mama representam em média 40% de todos os tumores, e sua carcinogênese é atribuída a interação complexa de fatores individuais da paciente. A enzima ciclooxigenase-2 (COX-2) apresenta-se como um marcador potencial para o câncer de mama, uma vez que é expressa em resposta a processos inflamatórios, que frequentemente acompanham as neoplasias e alterando o seu prognóstico. A caspase-3 é foco de estudos relacionados ao mecanismo da apoptose, tornando-se peça-chave no entendimento dos mecanismos de morte celular. O VEGF está envolvido na angiogênese e linfangiogênese, apresentando papel importante na progressão do câncer. O objetivo deste trabalho foi investigar a imunorreatividade da ciclooxigenase-2, do VEGF e da Caspase-3 nas neoplasias mamárias de cadelas, e correlacionar a expressão da COX-2 com o VEGF e com a Caspase-3, nesses tumores. Para a realização deste estudo foram selecionadas 60 amostras de tumores mamários de cadelas e 10 amostras de tecido mamário livre de malignidade que foram divididas em seis grupos compostos por 10 tumores de mesma classificação histológica cada grupo, e um grupo composto por 10 amostras de tecido mamário livre de malignidade. Os grupos foram denominados Adenomas, Carcinomas de prognóstico bom, Carcinomas de prognóstico ruim, Carcinomas primários metastáticos, Metástases pulmonares, Carcinomas inflamatórios e Controle. Os 7 grupos foram agrupados em micro-arranjo tecidual em lâmina de microscopia, e analisados através de imunoistoquímica pela técnica estreptavidina-biotina-peroxidase. A avaliação da intensidade de marcação foi obtida por densitometria com auxílio do programa ImageJ. A intensidade da marcação da Cox-2 foi maior nos casos de metástase pulmonar e fraca nos casos de... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In bitches, breast tumors represent an average of 40% from all tumors, and its carcinogenesis is attributed to a complex interaction of individual patient's factors. The enzyme cyclooxygenase-2 (COX-2) is presented as a potential marker for breast cancer, since it is expressed in response to inflammation, which are often associated with neoplasms, changing its prognosis. Caspase-3 has been investigated as a key-protein associated with the mechanism of apoptosis, becoming a key part in understanding the mechanisms of cell death. VEGF is involved in angiogenesis and lymphangiogenesis, presenting important role in cancer progression. The objective of this study was to investigate the immunoreactivity of cyclooxygenase-2, VEGF and Caspase-3 in mammary neoplasms in bitches, and correlate the expression of COX-2 and VEGF and the Caspase-3 in these tumors. For this study we selected 60 samples of bitches's mammary tumors and 10 samples of breast tissue malignancy's free, which were divided into six groups of 10 tumors of the same histological grade of each group and one group of 10 breast tissue samples malignancy's free. The groups were called adenomas, carcinomas good prognosis, carcinomas with poor prognosis, metastatic primary carcinomas, lung metastases, inflammatory carcinomas and Control. The seven groups were grouped into tissue micro-array on a microscope slide, and analyzed by immunohistochemistry technique streptavidin-biotin-peroxidase. The evaluation of the intensity of staining was obtained by densitometry using the program ImageJ. The intensity of COX-2 labeling was higher in cases of pulmonary metastasis and poor in cases of adenoma. In the assessment of marking of Caspase-3, there was a significant correlation between the control and carcinoma with poor prognosis (p <0.001) Furthermore, there was significant difference... (Complete abstract click electronic access below)
Mestre
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44

Ueda, Shugo. "Redox Regulation of Caspase-3(-like)Protease Activity : Regulatory Roles of Thioredoxin and Cytochrome c." Kyoto University, 2000. http://hdl.handle.net/2433/180831.

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45

Terra, Adriana Cristina. "Interferências do campo elétrico alternado externo em células tumorais e normais." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-30042010-090133/.

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Os campos elétricos alternados de frequência intermediária (10 KHz a 1MHz) e baixa intensidade têm efeitos inibitórios sobre o crescimento de várias linhagens celulares de tumores humanos e murinos. O objetivo geral do presente trabalho é conhecer os efeitos biológicos da aplicação externa de Campos Elétricos Alternados de intensidades de 10 V e 5 V nas frequências de 200kHz, 1Mhz e 2Mhz; em culturas de células de melanoma murino (B16F10) e fibroblastos humanos normais (FN1), durante 24 horas. Foram estudados os efeitos biológicos antiproliferativos e pró-apoptóticos através das seguintes análises: Citometria de Fluxo para identificar a distribuição das populações celulares nas fases do ciclo celular, Colorimétrico MTT para avaliar a viabilidade celular e Peroxidação Lipídica para avaliar a produção de radicais livres lipídicos poliinsaturados. Os resultados mostraram que em fibroblastos humanos normais o campo elétrico alternado induziu efeito antiproliferativo, indutor de necrose e apoptose, porém em menor efeito tóxico quando comparado às células de melanoma (B16F10), principalmente na frequência de 200 kHz. Por outro lado, na frequência de 2MHz e intensidade 10V, as células de melanoma presentes no sobrenadante e aderentes expressaram diferencialmente número de células mortas por apoptose (Anexina-V) e caspase-3 fosforilada. Os diferentes efeitos produzidos entre as duas linhagens estudadas atentam para o fato de que a compreensão dos mecanismos biofísicos da regulação do reparo e da proliferação celular envolve fenômenos celulares e vias de sinalização altamente complexas.
Electric fields of alternating intermediate frequency and low intensity have inhibitory effects on the growth of various tumor cell lines. The objective of this study was to evaluate the biological effects of external application of external alternating electric field (CEAE) intensities of 10 V and 5 V in the frequency 200kHz, 1MHz and 2MHz; in cultured murine melanoma cells (B16F10) and human fibroblasts normal (FN1). We studied the antiproliferative and pro-apoptotic by flow cytometry to identify the distribution of cell populations in the phases of the cell cycle, Colorimetric MTT to evaluate cell viability and lipid peroxidation to evaluate the production of free radicals lipid acids. The results showed that in fibroblasts (FN 1) the normal CEAE induced antiproliferative effect, inducing apoptosis and necrosis, but at a lower cytotoxic potential when applied to melanoma cells (B16F10), mainly in the frequency of 200 kHz. Moreover, the frequency of 2MHz and intensity 10V, the melanoma cells in supernatant and the members expressed differentially number of dead cells by apoptosis and caspase-3 phosphorylated. The different effects between the two strains studied to undermine the fact that understanding the biophysical mechanisms of regulation of repair and cell proliferation involves cellular phenomena and signaling pathways highly specific and complex.
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46

Leipelt, Juliano. "Avaliação in vitro do potencial biológico de Myrciaria plinioides (D. Legrand) em células tumorais." reponame:Repositório Institucional da UNIVATES, 2016. http://hdl.handle.net/10737/1110.

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O câncer é apontado como a segunda maior causa de morte em todo o mundo, com previsão de em breve ser tornar a primeira. O câncer de próstata está entre os 5 tipos de câncer mais diagnosticados em homens, sendo que o câncer hepático está em segundo lugar em taxa de mortalidade entre homens e mulheres. Indícios apontam para uma ativação das vias da inflamação associados a uma inibição das vias de morte celular no processo de carcinogênese. A regulação destas vias torna-se alvo importante e complementar no controle do câncer, sendo estimulada a busca de biomoléculas com este potencial. As plantas são importante fonte de descoberta de novas biomoléculas com ampla utilização para o tratamento de diversas patologias. A família Myrtaceae possui diversas espécies que são apontadas como fortes candidatos em potencial nesta busca, incluindo as do gênero Myrciaria. A espécie Myrciaria plinioides não possui estudos referentes suas propriedades terapêuticas ou a atuação em vias de sinalização envolvidas na inflamação ou na carcinogênese. Neste contexto, este estudo teve por objetivo avaliar a atividade do extrato etanólico de M. plinioides em células de carcinoma hepatocelular (HepG2) e próstata (LNCaP) , através da análise de expressão dos marcadores p38-α, pp38-α, NF-κB e caspase-3, envolvidos na carcinogênese, e o efeito sobre a viabilidade celular através do método de MTT. A viabilidade das células foi alterada significativamente, em ambas as linhagens celulares quando tratadas com o extrato etanólico. A análise da expressão proteica demonstra significativa inibição da expressão de p38-α e caspase-3 nas células LNCaP, quando tratadas com extrato etanólico de M. plinioides seguido de LPS. Em células HepG2, somente houve alteração na expressão da caspase-3 na concentração de 200 μg/mL, com ou sem adição de LPS após tratamento com extrato. Os resultados deste estudo demonstraram redução da viabilidade celular nas duas linhagens tumorais, expressão diferenciada de proteínas envolvidas em apoptose, o que leva a indícios da ativação de mecanismos distintos pelo extrato em cada tipo celular. Estudos futuros para averiguar o mecanismo celular e a indução de morte em células tumorais de câncer de próstata e de fígado podem contribuir para a identificação e elucidação de novas biomoléculas com potencial antitumoral.
Cancer is touted as the second leading cause of death worldwide, forecast to soon be making the first. Prostate cancer is among the five most cancers diagnosed in men, and liver cancer is second in mortality between men and women. Evidence points to the activation of pathways of inflammation associated with an inhibition of cell death pathways in carcinogenesis. The regulation of these pathways becomes important and complementary target in cancer control, and stimulated the search for biomolecules with this potential. The plants are important source of discovery of new biomolecules with wide use for the treatment of various diseases. The Myrtaceae family has many species that are identified as potential candidates strong in this search, including the Myrciaria genre. The species Myrciaria plinioides not have studies on its therapeutic properties or performance in signaling pathways involved in inflammation or carcinogenesis. In this context, this study aimed to evaluate the activity of the ethanol extract of M. plinioides in hepatocellular carcinoma cells (HepG2) and prostate (LNCaP) by expression analysis of p38-α markers, PP38-α, NF-kB and caspase-3, involved in carcinogenesis, and the effect on cell viability by the MTT method. The viability of cells was significantly altered in both cell lines when treated with ethanolic extract. Protein expression analysis demonstrates significant inhibition of p38-α expression and caspase-3 in LNCaP cells, when treated with ethanolic extract of M. plinioides followed by LPS. In HepG2 cells there was only a change in the expression of caspase-3 at a concentration of 200 / ml, with or without addition of LPS after treatment with extract. The results showed reduction of cell viability in both tumor lines, differential expression of proteins involved in apoptosis, leading to evidence of activation by distinct mechanisms in each extract cell type. Further studies to investigate the cellular mechanism, and induction of death in tumor cells of prostate and liver cancer may contribute to the identification and elucidation of new biomolecules with antitumor potential.
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47

Vegran, Frédérique. "Impact des marqueurs de l'apoptose sur la progression tumorale et la réponse aux traitements dans les cancers du sein." Dijon, 2007. http://www.theses.fr/2007DIJOMU03.

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Pour contourner le problème de chimiorésistance cancers du sein, il faut mettre en évidence de nouveaux marqueurs. Ainsi les gènes impliqués dans l’apoptose pourraient servir de marqueurs prédictifs. Notre étude, portant sur la survivine, la caspase-3 et leurs transcrits alternatifs a monté que la survivine-2B pourraient servir de marqueur prédictif et la survivine-3B de marqueur pronostic. Nous montrons également que l’expression des transcrits anti apoptotiques la survivine est régulée par p53. Par ailleurs, un site GATA-1 formé la présence d’un polymorphisme dans le promoteur de la survivine semble induire sa surexpression. Nos résultats indiquent que la survivine-3B pourrait inhiber la voie de récepteurs de mort et que la caspase-3s a une fonction fortement anti-apoptotique par interaction avec la caspase-3 après un stimulus apoptotique. L’ensemble de ces données met l’accent sur le rôle majeur des transcrits alternatifs des gènes de l’apoptose dans la réponse des cancers du sein à la chimiothérapie. Ils permettent d’envisager ces protéines comme de nouvelles cibles thérapeutiques
To avoid chemoresistance of breast cancers, prognosis and predictive markers are required. Apoptosis is highly involved in treatment response, that is why apoptosis genes could become predictive markers. Our study, dealing with survivin, caspase-3, and their alternative splice variants shows that survivin-2B could be a predictive marker and survivin-3B a prognosis marker. We also show that survivin and its anti-apoptotic variant over-expression could be linked to p53 mutations. Moreover, a polymorphism in survivin promoter induces a GATA-1 binding site able to overexpress survivin. Our results showed that survivin-3B could inhibit death receptors pathway and that caspase-3s is strongly anti-apoptotic by interaction of caspase-3 after an apoptotic stimulus. This work shows the major role of alternative splice variants of apoptosis genes in breast cancer response and strongly supports that these proteins as new therapeutic targets
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48

Harding, Charles P. "In Vitro Simulation of Microgravity Induced Muscle Loss Successfully Increases Expression of Key In Vivo Atrophy Markers." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7436.

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Muscle loss from lack of activity is a serious issue for immobilized patients on Earth and in human spaceflight, where the low gravity environment prevents normal muscle activity. Simulating muscle loss in cultured cells is an important step in understanding how this condition occurs. This work evaluates different means of simulating muscle loss and selects the one that most closely mimics the cellular responses seen in animals and humans. To simulate the microgravity environment of spaceflight, mouse skeletal muscle cells were grown in a rotary cell culture system (RCCS). Growing the cells within a natural gelled substrate was compared against growing them on the surface of small plastic beads. Changes after culture under simulated microgravity were characterized by assessing proteins and genes known to change during muscle loss. The structure of the cells was also evaluated by microscopy. The mouse skeletal muscle cells grown on plastic beads in the RCCS had significant changes in multiple key genes associated with muscle loss and demonstrated physical characteristics expected of mature tissue in live animals. This model is a valuable platform for exploring muscle loss mechanisms and testing new drugs.
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49

Kjellerås, Jennifer. "1,25(OH)2D3 increase caspase-3 activity in LNCaP cells after 2 minutes and 48h separately." Thesis, University of Skövde, School of Life Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-474.

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Cancer or malignant tumors has a high death frequency in many countries. Nowadays many research facilities are dedicated to find new substances and techniques which would lead to better cancer therapies. Seven years ago a research team from Finland made a remarkable connection between vitamin D deficiencies and an increased chance of getting prostate cancer. The research investigating this statement has lead to findings of a new non-classical effect of the calcium controlling vitamin, 1,25(OH)2D3. This effect involves anti-proliferatory effects and more importantly apoptotic effects resulting in the hope of finding a new drug that can cure prostate cancer with the smallest amount of harm to the body.

In an attempt to find out if the signalling pathway of this apoptotic effect is fast or slow, an experiment designed to detect when the apoptotic protein caspase-3 is induced has been performed. Cells from the cell line LNCaP has been cultured and incubated with 1,25(OH)2D3 and after 0min - 48h an assay was performed to detect the relative amounts of caspase-3 present in every sample. The optimal time period (48h) was then subjected to three different concentrations of 1,25(OH)2D3 and read in the same way as the previous samples. The results showed an increase in caspase-3 expression as early as 2 min, but disappear to be seen again at 24h and are more profound in 48h samples. The caspase-3 expression was also seen to form a possible exponential curve in dose-response.

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50

Ayala-Grosso, Carlos Alberto. "Caspase-3 and calpain activation in Alzheimer's disease and a rat model of septo-hippocampal injury." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84464.

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In this study, markers of programmed cell death were examined in the superior temporal, parietal and inferior frontal cortices of age-matched and Alzheimer's brain tissues and in the septum and dorsal hippocampus from fimbria-fornix axotomized rats. Activation of proteases belonging to the caspase and calpain family has been implicated in the mediation of programmed cell death in acute injury and chronic neurodegenerative disorders. The main risk factor for Alzheimer's disease, aging, is associated with a gradual impairment of critical cellular homeostasis processes such as glucose metabolism, mitochondrial integrity and scavenging of reactive oxygen species. These changes in concert with dysmetabolism of the amyloid precursor protein and/or the microtubule associated protein Tau may compromise cell function beyond a threshold that commits neurons to die. Programmed cell death, a highly regulated pathway that entails an organized disassembly of the cell may contribute to the progression of neuropathology in Alzheimer's disease. Using antibodies to neo-epitopes generated by caspase-3-mediated cleavage of the amyloid precusor protein and spectrin, I have localized by immunohistochemistry these caspase-3-generated neo-epitopes in autopsied Alzheimer's and age-matched control brains, as well as in the forebrain of rats that have been subjected to axotomy of the septo-hippocampal pathway. Elevated levels of caspase-3-cleaved amyloid precursor protein were detected in Alzheimer's disease with respect to age-matched control brains. Immunopositive profiles were observed in particulate elements resembling dystrophic neurites, as well as in dense-core neuritic plaques, and in a subpopulation of neurons and glial cells. Caspase-3 cleaved amyloid precursor protein co-localized with some TUNEL-positive cortical neurons indicating that DNA fragmentation was indeed occurring in neurons undergoing programmed cell death. However, while there was some overl
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