Thèses sur le sujet « Preadipociti »
Pour voir les autres types de publications sur ce sujet consultez le lien suivant : Preadipociti.
Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres
Consultez les 50 meilleures thèses pour votre recherche sur le sujet « Preadipociti ».
À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.
Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.
Parcourez les thèses sur diverses disciplines et organisez correctement votre bibliographie.
1
MARMO, ROSA. « Riprogrammazione di preadipociti umani mediante trattamento chimico ». Doctoral thesis, Università degli studi di Padova, 2010. http://hdl.handle.net/11577/3426538.
Texte intégralRésumé :
Recent studies have shown that differentiated mammalian cells may de-differentiate by forced expression of defined factors for pluripotency; biomedical research is seeking optimizing techniques for obtaining iPS cells without the use of viral genetic material. The purpose of this work was to obtain iPS cells virus-free using the strategy work proposed below:
- Extraction of precursors from adipose tissue of healthy subject and cultured in Preadipocyte Growth Medium or in DMEM added with 10% FCS.
- Characterization of these cells by research of specific nuclear, cytoplasmic and surface markers; for this purpose it has been invoked in a series of methods including flow cytometry analysis, molecular and cytochemical (immunofluorescence, Oil Red O) essays;
- Treatment of cells with 5-azacitidine 10 μM for 48-96 hours;
- Performing tests of cell viability (MTT) and daily observation by light microscopy at to monitor the morphology and growth of cells treated with azacitidine.
- Real Time PCR order to characterize the cells "reprogrammed" to molecular level, or to check the over-expression of stem cells genes (OCT-4, Nanog, Sox-2) and the down-regulation of tissue-specific genes.
- Evaluation of the expression of transcription factors stem cells specific through Western blot analysis.
- Analysis by confocal microscopy and cytometry to define the characteristics morphological and phenotypic of cells treated with demethylating agent and "reprogrammed".Recenti studi hanno dimostrato che cellule di mammifero differenziate possono de-differenziarsi mediante espressione forzata di definiti fattori per la pluripotenza; la ricerca biomedica sta cercando di ottimizzare le tecniche per l'ottenimento di cellule iPS senza l'uso di materiale genetico virale. Scopo di questo lavoro è stato quello di ottenere cellule iPS virus-free utilizzando la strategia di lavoro proposta di seguito: -Estrazione di precursori da tessuto adiposo di soggetto sano e coltura delle stesse in Preadipocyte Growth Medium o in DMEM addizionato con FCS al 10%. -Caratterizzazione delle stesse cellule mediante ricerca di specifici marcatori nucleari, citoplasmatici e di superficie; a tale scopo ci si è avvalsi di una serie di metodiche tra cui l’analisi citofluorimetrica, saggi citochimici (immunofluorescenza, Oil Red O) e molecolari; -Trattamento delle cellule con 5-azacitidina 10 μM per 48-96 ore; -Esecuzione di saggi di vitalità cellulare (MTT) e osservazione giornaliera mediante microscopia ottica allo scopo di monitorare la morfologia e la crescita delle cellule trattate con azacitidina. -Realizzazione di indagini di Real Time PCR allo scopo di caratterizzare le cellule “riprogrammate” a livello molecolare, ovvero per verificare la sovra-espressione di geni indicatori di staminalità (OCT-4, Nanog, Sox-2) e la down-regolazione di geni tessuto specifici. -Valutazione dell’espressione di fattori di trascrizione specifici delle cellule staminali mediante analisi Western Blot. -Analisi mediante microscopia confocale e citofluorimetria per la definizione delle caratteristiche morfologiche e fenotipiche delle cellule trattate con l’agente demetilante e “riprogrammate”.
2
Stasi, Fabio. « Caratterizzazione delle cellule staminali del tessuto adiposo nell'obesità e nel diabete : effetto del calo ponderale ». Doctoral thesis, Università degli studi di Padova, 2015. http://hdl.handle.net/11577/3423904.
Texte intégralRésumé :
INTRODUCTION: The Stromal Vascular Fraction (SVF) of human adipose tissue (AT) contains different subpopulations identified by specific CD membrane markers. We focused on the role of preadipocytes (CD34+/CD31-/CD45-), endothelial precursors (CD34+/CD31+/CD45-) and pericytes (CD146+) in obesity and AT remodeling, and the possible pathological correlation between the preadipocyte content and obesity development.
MATERIALS AND METHODS: Abdominal subcutaneous (SAT) and visceral AT (VAT) were obtained from 7 obese and 6 obese/diabetic patients underwent sleeve gastrectomy, 7 obese patients underwent plastic surgery or cholecystectomy after a >10kg weight loss. SVF was isolated by collagenase digestion and characterized measuring the co-expression of CD34, CD90, CD73, CD13, CD29, CD271, CD31, CD146 by flow cytometry. We evaluated the expression profiles by qPCR, adipogenic potential, proliferation capacity and morphological features during culture. We sorted by FACS the different subpopulations and in vitro evaluated their adipogenic and angiogenic potential.
RESULTS: The flow cytometric analysis revealed a higher % of preadipocytes in VAT than in SAT, with significant differences in obese DM2 (41.9 % ± 3.2 % VAT vs 23.1 % ± 2.9 % SAT) and a significant increase in preadipocytes in SAT of post-obese, up to 70%. Are rather higher percentages of endothelial precursors in SAT than in VAT, for both categories of patients. SVF cells are positive for most of the markers of mesenchymal stem cells (CD13, CD29, CD90, CD73) with the exception of CD271 which shows differences between the two fat depots analyzed. Finally, there is a higher content of CD146+/CD31-/ CD34- pericytes in SAT of the obese and obese DM2, and a greater portion of cells CD146+/CD31+/CD34- especially in SAT of the obese with DM2. The SVF ex vivo (P0) shows the higher adipogenic potential that decreases during the passages in culture (P1-P4) along with the down-regulation of CD34 mRNA and Zfp423, and the up-regulation of CD90. We observed an increase in cell size and nuclear dimensions, along with changes in cytoskeletal structures. The subpopulation of preadipocytes showed the highest adipogenic potential.
CONCLUSIONS: the VAT of obese and obese DM2, with a higher content of preadipocytes shows more hyperplastic features than SAT, which having a greater number of endothelial progenitor cells and pericytes has more pro-angiogenic features. However, under conditions of weight loss that occurs in obese patients following surgical treatment, SAT acquires the characteristics of the VAT in the conditions of obesity, increasing the content in preadipocytes. The loss of adipogenic potential associated with the down-regulation of CD34, and the presence of this marker in preadipocytes of SVF demonstrates its strong involvement in adipogenesis. SVF cells undergo deep morphological changes during expansion in vitro, suggesting a possible connection between the cytoskeletal structures and the expression of stem cell markers.INTRODUZIONE: la frazione vasculo stromale (SVF) del tessuto adiposo umano contiene differenti sottopopolazioni identificate da specifici marcatori di membrana (CD). Abbiamo focalizzato l’attenzione sul ruolo dei preadipociti (CD34+/CD31-/CD45-), precursori endoteliali (CD34+/CD31+/CD45-) e periciti (CD146+) nell’obesità e rimodellamento del tessuto adiposo, e la possibile correlazione patologica nel contenuto di preadipociti nello sviluppo dell’obesità. MATERIALI E METODI: tessuto adiposo sottocutaneo addominale (SAT) e viscerale (VAT) sono stati prelevati da 7 pazienti obesi e 6 pazienti obesi con diabete mellito di tipo 2 (DM2) sottoposti a bendaggio gastrico, 7 pazienti post-obesi sottoposti ad operazione di chirurgia plastica (addominoplastica) dopo calo ponderale superiore ai 10 Kg. La SVF è isolata mediante digestione enzimatica con collagenasi e caratterizzata misurando la co-espressione del CD34 con il CD90, CD73, CD13, CD29, CD271, CD31, CD146 mediante citofluorimetria. Abbiamo valutato i profili di espressione genica mediante qPCR, analisi del potenziale adipogenico, capacità proliferativa e caratteristiche morfologiche durante i passaggi in coltura. Abbiamo effettuato sorting mediante FACS delle differenti sottopopolazioni della SVF e valutato in vitro il loro potenziale adipogenico. RISULTATI: Le analisi citofluorimetriche hanno rivelato una % più alta di preadipociti nel VAT rispetto al SAT, con differenze significative nei pazienti obesi DM2 (41.9% ± 3.2% VAT vs 23.1% ± 2.9% SAT) e un consistente incremento dei preadipociti nel SAT dei post-obesi, fino al 70%. Risultano invece percentuali maggiori di precursori endoteliali nel SAT rispetto al VAT, per entrambe le categorie di pazienti. Le cellule della SVF risultano positive per la maggior parte dei marcatori delle staminali mesenchimali (CD13, CD29, CD90, CD73) ad eccezione del CD271 il quale mostra differenze tra i due depositi adiposi analizzati. Infine, vi è un contenuto maggiore di periciti CD146+/CD31-/CD34- nel SAT degli obesi e degli obesi DM2, e un quantitativo superiore di cellule CD146+/CD31+/CD34- soprattutto nel SAT degli obesi affetti da DM2. La SVF ex-vivo (P0) mostra il potenziale adipogenico più elevato che diminuisce durante i passaggi in coltura (P1-P4) insieme alla down-regolazione dell’mRNA del CD34 e di Zfp423, e alla up-regolazione del CD90. Abbiamo osservato un incremento nelle dimensioni cellulari e nucleari, insieme a cambiamenti delle strutture citoscheletriche. La frazione dei preadipociti ha mostrato il più alto potenziale adipogenico. CONCLUSIONI: il VAT degli obesi e degli obesi DM2, con un contenuto maggiore di preadipociti dimostra possedere maggiori caratteristiche iperplastiche rispetto al SAT, il quale avendo un numero maggiore di precursori endoteliali e di periciti presenta maggiori caratteristiche pro-angiogeniche. Tuttavia, in condizioni di calo ponderale che avviene nei pazienti obesi in seguito a trattamento chirurgico, il SAT acquisisce le caratteristiche del VAT nelle condizioni di obesità, aumentando il contenuto in preadipociti. La perdita del potenziale adipogenico associata alla down-regolazione del CD34, e la presenza di tale marcatore nei preadipociti della SVF dimostra un suo forte coinvolgimento nell’adipogenesi. Le cellule della SVF vanno incontro a profondi cambiamenti morfologici durante l’espansione in vitro, suggerendo una possibile connessione tra le strutture citoscheletriche e l’espressione di marcatori della staminalità.
3
Hutley, Louise Joyce. « Human preadipocyte proliferation and differentiation ». Thesis, Queensland University of Technology, 2002. https://eprints.qut.edu.au/37117/6/37117_Digitised_Thesis.pdf.
Texte intégralRésumé :
Obesity represents a major health, social and economic burden to many developing and Westernized communities, with the prevalence increasing at a rate exceeding almost all
other medical conditions. Despite major recent advances in our understanding of adipose tissue metabolism and dynamics, we still have limited insight into the
regulation of adipose tissue mass in humans. Any significant increase in adipose tissue mass requires proliferation and differentiation of precursor cells (preadipocytes) present in the stromo-vascular compartment of adipose tissue. These processes are very
complex and an increasing number of growth factors and hormones have been shown to modulate the expression of genes involved in preadipocyte proliferation and
differentiation. A number of transcription factors, including the C/EBP family and PP ARy, have been identified as integral to adipose tissue development and preadipocyte
differentiation. Together PP ARy and C/EBPa regulate important events in the activation and maintenance of the terminally differentiated phenotype. The ability of
PP ARy to increase transcription through its DNA recognition site is dependent on the
binding of ligands. This suggests that an endogenous PP ARy ligand may be an important regulator of adipogenesis. Adipose tissue functions as both the major site of
energy storage in the body and as an endocrine organ synthesizing and secreting a number of important molecules involved in regulation of energy balance. For optimum
functioning therefore, adipose tissue requires extensive vascularization and previous studies have shown that growth of adipose tissue is preceded by development of a
microvascular network. This suggests that paracrine interactions between constituent cells in adipose tissue may be involved in both new capillary formation and fat cell
growth. To address this hypothesis the work in this project was aimed at (a) further development of a method for inducing preadipocyte differentiation in subcultured
human cells; (b) establishing a method for simultaneous isolation and separate culture of both preadipocytes and microvascular endothelial cells from the same adipose tissue
biopsies; (c) to determine, using conditioned medium and co-culture techniques, if endothelial cell-derived factors influence the proliferation and/or differentiation of
human preadipocytes; and (d) commence characterization of factors that may be responsible for any observed paracrine effects on aspects of human adipogenesis.
Major findings of these studies were as follows:
(A) Inclusion of either linoleic acid (a long-chain fatty acid reported to be a naturally occurring ligand for PP ARy) or Rosiglitazone (a member of the thiazolidinedione class of insulin-sensitizing drugs and a synthetic PPARy ligand) in differentiation medium had markedly different effects on preadipocyte differentiation. These studies showed that human preadipocytes have the potential to accumulate triacylglycerol irrespective of their stage of biochemical differentiation, and that thiazolidinediones and fatty acids may exert their adipogenic and lipogenic effects via different biochemical pathways. It
was concluded that Rosiglitazone is a more potent inducer of human preadipocyte differentiation than linoleic acid.
(B) A method for isolation and culture of both endothelial cells and preadipocytes from the same adipose tissue biopsy was developed. Adipose-derived microvascular endothelial cells were found to produce factor/s, which enhance both proliferation and differentiation of human preadipocytes.
(C) The adipogenic effects of microvascular endothelial cells can be mimicked by exposure of preadipocytes to members of the Fibroblast Growth Factor family, specifically ~-ECGF and FGF-1. (D) Co-culture of human preadipocytes with endothelial cells or exposure of
preadipocytes to either ~-ECGF or FGF-1 were found to 'prime' human preadipocytes, during their proliferative phase of growth, for thiazolidinedione-induced differentiation. (E) FGF -1 was not found to be acting as a ligand for PP ARy in this system. Findings from this project represent a significant step forward in our understanding of factors involved in growth of human adipose tissue and may lead to the development of
therapeutic strategies aimed at modifying the process. Such strategies would have potential clinical utility in the treatment of obesity and obesity related disorders such as
Type II Diabetes.
4
Peshdary, Vian. « Effect of Glucose on Human Adipogenesis and its Regulation by Macrophages ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35051.
Texte intégralRésumé :
Adipose tissue expands via differentiation of preadipocytes into adipocytes (adipogenesis) and/or hypertrophy of existing adipocytes. A low adipogenic capacity promotes adipocyte hypertrophy, causing inflammatory macrophage accumulation and insulin resistance. Macrophage-conditioned medium (MacCM) inhibits adipogenesis and promotes adipocyte inflammation, but it is unknown if these effects are altered by high glucose (HG) versus normal glucose (NG) concentrations. The effect of HG on adipogenesis was assessed. Human subcutaneous abdominal preadipocytes were induced to differentiate in HG or NG conditions. HG did not affect adipogenesis. HG increased ChREBP-β mRNA and protein levels, and increased GLUT4 mRNA, in differentiated adipocytes. It did not change mRNA levels of ACC, SCD, and FAS. The increase in ChREBP-β mRNA was positively correlated with HG-induced increase in GLUT4 mRNA. The effect of HG-MacCM versus NG-MacCM on human adipogenesis and adipocyte inflammation was compared. Human monocyte-derived macrophages (MDM) were placed in NG or HG glucose for 24 hours to generate MacCM. HG-MacCM, but not NG-MacCM inhibited triacylglycerol accumulation and protein expression of PPARγ during human adipogenesis. Preadipocytes differentiated in HG-MacCM displayed a more pro-inflammatory phenotype, as assessed by increased MCP-1 and IL-6 and reduced adiponectin mRNA expression. HG increased phosphorylation of IKK-β and decreased protein expression of IκBα in MDMs. In addition, HG reduced protein expression of PPARγ in MDMs. The pro-inflammatory effect of HG-MacCM on MCP-1 expression in adipocytes was partially inhibited when MDMs were treated with sc-514 (IKKβ inhibitor). My data demonstrate that HG-induced expression of ChREBP-β in adipocytes may be associated with increased GLUT4 mRNA. The anti-adipogenic and pro-inflammatory effects of HG-MacCM are more potent than NG-MacCM. This suggests the possibility that adipose tissue cellular remodeling in vivo may be altered with hyperglycemia.
5
Hattingh, Anna C. « The anti-ageing potential of rooibos : preserving preadipocyte funtion ». Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/7804.
Texte intégralRésumé :
Treatments with natural products rich in anti-oxidants have attracted remarkable interest in the cosmetic and pharmaceutical industry to combat oxidative stress and reverse the effects of ageing. Rooibos (Aspalathus linearis) is a South African fynbos plant, well-known for its strong anti-oxidant capacity and use in many cosmetic products. However, little published research exists on its potential as an anti-ageing treatment. The anti-ageing properties of fermented and green rooibos were investigated using an in vitro cell culture model designed to evaluate the involvement of mitochondrial dysfunction in the age related decline in preadipocyte function. Mitochondrial DNA (mtDNA) deficient preadipocytes, ρ0 3T3-L1preadipocytes, were generated following continuous long-term exposure to sub lethal concentrations of ethidium bromide (EtBr). Depletion of the mtDNA resulted in a significantly reduced mitochondrial membrane potential, rate of proliferation in culture, as well as an increased glucose utilization and lactate production. Treatment with the green rooibos (100 μg/mL) stimulated cell growth rates for both the wildtype and mutant cell lines. MtDNA depleted cells showed arrest in the G1 phase (48.8 ± 3.34%) compared to wildtype cells (44.6 ± 1.38%), which was significantly attenuated after treatment with green rooibos for mutant (42.0 ± 0.83%) and wildtype (36.5 ± 5.80%) treated cells. The results obtained for glucose utilization and lactate production, indicated a significant increase in glucose utilization along with a concomitant increase in lactate production after treatment with both green and fermented rooibos for wildtype and mutant cell lines. A significant improvement in mitochondrial membrane potential was also later observed after treatment with green and fermented rooibos on both the wildtype and mutant cell lines. The results obtained indicate that rooibos extracts, particularly the green rooibos, exhibit effects which preserve the functional capacity of preadipocytes exposed to ageing related insults, and indicate that rooibos could cause a metabolic shift in cells redirecting carbon flow away from mitochondrial metabolism, and towards lactate production and consequently, cells become resistant to mitochondrial dysfunction.
6
Molgat, André. « The Effect of Macrophage-secreted Factors on Preadipocyte Survival ». Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/23628.
Texte intégralRésumé :
Adipose tissue (AT) expansion and remodeling that maintains healthy function relies on stromal preadipocytes capable of differentiating into new adipocytes (adipogenesis). During chronic positive energy balance, a relative deficit in adipogenesis, from either a decrease in preadipocyte number or their capacity to differentiate, leads to excessive adipocyte hypertrophy and AT dysfunction. AT contains macrophages whose number and activation state is dynamically regulated with changes in AT mass. This study aims to investigate the effect of macrophage-secreted factors on preadipocyte survival.
To assess the effect of macrophage-secreted factors on preadipocytes, murine 3T3-L1 preadipocytes or human primary preadipocytes were incubated with macrophage-conditioned medium (MacCM), prepared from either murine (J774A.1, RAW264.7, bone marrow-derived) or human (THP-1, monocyte-derived) macrophage models, respectively. MacCM inhibited preadipocyte apoptosis and activated pro-survival signaling in both preadipocyte models. Inhibition of PDGFR, Akt, or ERK1/2 reduced the pro-survival effect of MacCM in 3T3-L1 preadipocytes. Inhibition of reactive oxygen species (ROS) generation, or enhancement of ROS clearance, reduced MacCM-dependent 3T3-L1 preadipocyte survival. Whereas anti-inflammatory activated macrophages retained the ability to prevent preadipocyte apoptosis, pro-inflammatory activated macrophages did not. TNF-α immunoneutralization restored the survival activity of pro-inflammatory MacCM on 3T3-L1 preadipocytes.
These studies reveal a novel pro-survival effect of MacCM on preadipocytes, and identify signaling molecules (PDGF, Akt, ERK1/2, and ROS) that underlie this action. Macrophage activation was found to regulate the pro-survival activity of MacCM. These in vitro cell culture studies are consistent with a model in which the extent of preadipocyte apoptosis in vivo may determine preadipocyte number and the ability of AT to expand while maintaining healthy function during chronic positive energy balance.
7
El, Bilali Jason. « Effects of Chronic Insulin and High Glucose on Insulin-Stimulated Responses in Human Preadipocytes ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34109.
Texte intégralRésumé :
The preadipocyte is crucial for healthy adipose tissue (AT) remodeling, and insulin resistance in these cells may contribute to AT dysfunction. Chronic exposure to insulin and high glucose induces insulin resistance in the 3T3-L1 mouse adipocyte cell line in vitro, however, whether this occurs in human preadipocytes is not known. To investigate this, human preadipocytes were isolated from subcutaneous AT obtained from 6 female patients undergoing elective surgery (Research Ethics Board-approved). Human preadipocytes were incubated in 5 mM glucose or 25 mM glucose in the presence or absence of 0.6 nM insulin for 48 hours, followed by acute 100 nM insulin stimulation. 25 mM glucose + 0.6 nM insulin inhibited insulin-stimulated tyrosine phosphorylation of IR-β (77%) and IRS-1 (81%) compared to NG (p<0.01), however, insulin-stimulated Ser473 Akt phosphorylation was not affected. 25 mM glucose and/or 0.6 nM insulin did not significantly change levels of pro-inflammatory adipokines. 25 mM glucose and/or 0.6 nM, prior to and/or during 14 days of adipogenic induction, did not affect levels of adipogenic markers or intracellular triglyceride accumulation.
8
Nguyen, Anh Thu. « Effects of the HIV-1 protease inhibitor ritonavir on preadipocyte differentiation ». Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9001.
Texte intégralRésumé :
HIV-1 protease inhibitor therapy is associated with a novel lipodystrophy syndrome characterized by truncal adiposity, peripheral fat atrophy, dyslipidemia, and type 2 diabetes. The increase in truncal fat may be due to increase in adipocyte number as a result of enhanced preadipocyte differentiation. We show that addition of 10 mug/ml ritonavir to standard differentiation medium enhanced 3T3-L1 preadipocyte differentiation as measured by a 30% increase in triacylglycerol (TG) accumulation and a 50% increase in glycerol 3-phosphate dehydrogenase (GPDH) activity. Although ritonavir partially inhibited protein expression of peroxisome proliferator activated receptor gamma (PPARgamma), CCAAT/enhancer binding protein alpha (C/EBPalpha), and the aP2 gene (which encodes the adipocyte lipid binding protein), it resulted in higher levels of the active form of adipocyte determination and differentiation-dependent factor-1 (ADD-1), also known as sterol regulatory element binding protein 1 (SREBP-1). The enhancing effects of ritonavir on late events of 3T3-L1 preadipocyte differentiation may be mediated by ADD-1/SREBP-1 which has been shown to directly activate transcription of several genes encoding lipogenic enzymes. Preliminary results suggest that ritonavir preferentially enhances differentiation of human preadipocytes derived from abdominal omental but not subcutaneous adipose tissue in primary culture.
9
Yarwood, Stephen J. « The cyclic amp signalling system as a regulator of preadipocyte differentiation ». Thesis, University of Glasgow, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362948.
Texte intégral
10
Wurst, Ulrike. « Die Regulation von Preadipocyte factor-1 bei Gestationsdiabetes mellitus und Präeklampsie ». Doctoral thesis, Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-216381.
Texte intégralRésumé :
Adipositas und die damit verbundenen Begleiterkrankungen zeigen einen deutlichen Anstieg der Prävalenz in der Bevölkerung. Auch für die Schwangerschaft gilt starkes Übergewicht als Risikofaktor für metabolische und vaskuläre Komplikationen wie Gestationsdiabetes mellitus (GDM) und Präeklampsie (PE). In den letzten 20 Jahren wurde eindrücklich nachgewiesen, dass eine Dysregulation von Fettzell-sezernierten Proteinen, sogenannten Adipokinen, ursächlich zu GDM und PE beitragen könnte. Zu Beginn der Dissertation lagen jedoch nur unzureichende Daten über die Regulation des Insulinresistenz-induzierenden, anti-adipogenen und anti-angiogenen Adipokins Preadipocyte factor-1 (Pref-1) bei GDM und PE vor. Die vorliegende Arbeit untersucht daher die Regulation von zirkulierendem Pref-1 bei GDM und PE sowie seine Expression in der Plazenta. Bei 74 Patientinnen mit GDM konnte kein signifikanter Unterschied der Pref-1 Konzentrationen (0.40 µg/l) verglichen zu 74 Gesunden (0.42 µg/l) (p = 0.655) festgestellt werden (Wurst U et al., Cytokine 2015; 71: 161–164). Es zeigte sich in der Kohorte eine unabhängige Assoziation zwischen Pref-1 und Schwangerschaftsalter bei der Blutentnahme, Triglyzeriden, Kreatinin, Body Mass Index und C reaktivem Protein (p < 0.05). In einer Studienkohorte von 51 Schwangeren mit PE wurden signifikant niedrigere Serumspiegel von Pref-1 (0.49 µg/l) im Vergleich zu 51 gesunden Schwangeren (0.68 µg/l) (p < 0.001) gemessen (Schrey S, Wurst U, et al., Cytokine 2015; 75: 338–343). In der multiplen Regressionsanalyse waren PE, Schwangerschaftsalter zum Zeitpunkt der Blutentnahme sowie zirkulierendes Leptin unabhängige Prädiktoren für Pref-1. Im peripartalen Zeitraum zeigte sich ein akuter und deutlicher Abfall von zirkulierendem Pref-1 im mütterlichen Blut und das Adipokin wurde immunhistochemisch im Plazentagewebe nachgewiesen. Die Daten dieser Studien sind vereinbar mit den Hypothesen, dass Pref-1 mit fortschreitender Schwangerschaft zunehmend produziert wird, die Plazenta zur Sekretion des Adipokins aktiv beiträgt sowie das Adipokin bei PE dysreguliert ist. Weiterführende Untersuchungen im Tiermodell sowie prospektive Studien sind notwendig, um die Signifikanz von Pref-1 bei GDM und PE näher zu untersuchen.
11
Montague, Carl Thomas. « Adipose depot-specific differences in human adipocyte gene expression and preadipocyte differentiation ». Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624699.
Texte intégral
12
Ide, Jennifer C. « Effects of Macrophage-conditioned Medium on Preadipocyte Cyclin-dependent Kinase Regulation During Adipogenesis ». Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19752.
Texte intégralRésumé :
Macrophage-conditioned medium (MacCM) inhibits the differentiation of rodent and human preadipocytes. Previous studies report that murine J774A.1-MacCM inhibits clonal expansion (early required phase of adipogenesis), including Rb phosphorylation. I hypothesized that MacCM induced alterations in cyclins and/or cyclin-dependent kinases (CDKs) were responsible for impairing Rb phosphorylation. My first objective was to assess the effect of J774A.1-MacCM on CDK4, CDK2, and their regulatory cyclins. Murine 3T3-L1 preadipocytes were differentiated with control medium or J774A.1-MacCM. Expression of cyclin D and A was inhibited by J774A.1-MacCM. Inhibition of cyclin A expression was associated with reduced differentiation-induced CDK2 activity. My second objective was to assess the expression patterns of cell cycle proteins in differentiating human abdominal subcutaneous preadipocytes, which do not undergo clonal expansion in culture. Cyclin E expression increased with differentiation. THP-1-MacCM (a human macrophage cell line) further enhanced this increase. My studies suggest MacCM leads to alterations in cyclin/CDK regulation during adipogenesis in murine and human preadipocyte models.
13
Wiper, Nadine Louise. « Regulation of CEBPbeta transcription and preadipocyte differentiation by histone deacetylase 1 and GCN5 ». Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/29181.
Texte intégralRésumé :
Previous studies in this laboratory demonstrated that the glucocorticoid receptor (GR) ligand binding domain (LBD) can enhance transcription mediated by the CCAAT/enhaner binding protein C/EBPbeta. This result suggests that the receptor can act in a non-classical manner to positively affect transcription without directly binding DNA.
To study the physiological impact of the potentiation of C/EBPbeta activity by the GR LBD, we focused on preadipocyte differentiation as both GR and C/EBPbeta influence early events. Using retroviral expression of the GR LBD in 3T3 L1 cells, a 3-fold increase in preadipocyte differentiation was observed when cultures were induced to differentiate in a cocktail containing dexamethasone. The GR LBD was also able to enhance transcription mediated by DNA-bound C/EBPbeta from the C/EBPalpha promoter and its expression increased C/EBPbeta protein levels during preadipocyte differentiation. The effect of the GR LBD was accomplished through the targeted degradation of a sub-population of the transcriptional repressor histone deacetylase 1 (HDAC1), which associates with C/EBPbeta via corepressor protein mSin3A. In the absence of glucocorticoids, HDAC1 maintains the C/EBPalpha promoter in a deacetylated state. The addition of steroid to the differentiation cocktail causes the degradation of the HDAC1 found in the CIEBPbeta-associated complex, a release of mSin3A, increased acetylation of the promoter histone H4 and recruitment of RNA polymerise II leading to maximal transcription from the C/EBPalpha promoter.
C/EBPbeta itself is acetylated by the histone acetyltransferases GCN5 and PCAF within lysines 98, 101 and 102. In 3T3 L1 preadipocytes where only GCNS is expressed, GCNS coprecipitates with C/EBPbeta and can be found at the C/EBPalpha promoter by chromatin immunoprecipitation. The acetylation of C/EBPbeta is essential for development of full transcriptional activation potential and for differentiation of preadipocytes. Mutation of these residues leads to loss of transcriptional potentiation by GR and a striking decrease in the number of differentiated cells in both NIH 3T3 and 3T3 L1 cultures. Following glucocorticoid treatment, the mutant C/EBPbeta remains associated with HDAC1 and is inefficient in driving C/EBPalpha transcription. Acetylation may be a required modification to prevent C/EBPbeta from repression by HDAC1.
14
De, Sousa Peixoto Ricardo. « The role of preadipocyte 11β hydroxysteroid dehydrogenase type 1 in regional fat distribution ». Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/1974.
Texte intégralRésumé :
Glucocorticoid excess promotes visceral obesity, which is closely associated with morbidity and cardiometabolic disease. Similar features are found in the Metabolic Syndrome in the absence of elevated plasma cortisol. Whilst elevated activity of the intracellular glucocorticoid amplifying enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) within adipocytes might explain this paradox, the potential role of preadipocyte 11β-HSD1 is less clear. Data from murine cell lines suggested 11β-HSD1 was expressed at late stages of preadipocyte differentiation, where it exhibited keto-reductase activity, converting inactive into active glucocorticoids. In contrast, data from human preadipocytes suggested expression of 11β-HSD1 inactivated glucocorticoids (dehydrogenase action) in a depot-specific manner. In this study 11β-HSD1 mRNA levels and activity in homogenates were measured in preadipocyte-enriched stromal/vascular fraction (SVF), from metabolically “disadvantageous” visceral (mesenteric) and “safer” peripheral (subcutaneous) adipose tissue in mice. The results suggest that levels of 11β- HSD1 mRNA and enzyme are similar, within a given adipose tissue depot, in freshly isolated SVF and adipocytes. Crucially, 11β-HSD1 exclusively functioned as a keto-reductase in intact SVF, whatever the adipose depot of origin. Consistent with this, hexose-6-phosphate dehydrogenase (H6PDH), which drives 11β-HSD1 keto-reduction, is expressed in SVF. Unexpectedly, glucocorticoid reactivation was higher in freshly isolated intact mesenteric SVF cells than those from subcutaneous adipose, despite lower levels of 11β- HSD1 mRNA and enzyme in mesenteric SVF, suggesting a novel posttranscriptional control over enzyme activity. Mice with a targeted deletion of 11β-HSD1 (11β-HSD1-/-) showed no difference in expression of pref-1 (a preadipocyte marker) in adipose tissue, compared to control C57BL/6J mice, suggesting that 11β-HSD1 has no influence on preadipocyte proliferation. Upon high fat feeding, higher preadipocyte differentiation, as inferred from pref-1 mRNA levels, was higher within mesenteric than subcutaneous fat in 11β-HSD1+/+ mice. This differed from 11β-HSD1-/- mice where preadipocyte differentiation was greater in subcutaneous than mesenteric fat. These observations corroborate the literature in which mesenteric fat accumulation is more pronounced in 11β- HSD1+/+ mice than in 11β-HSD1-/-. Further, following HF diet, 11β-HSD1 and GR mRNA expression in SVF were decreased more markedly in mesenteric than in subcutaneous fat in 11β-HSD1+/+. This suggests an adaptive mechanism to counteract detrimental effects of high GC levels occurring at both pre-receptor and receptor level, mainly in the mesenteric adipose. Preliminary data from human preadipocytes suggested lower levels of 11β-HSD1 activity in preadipocytes compared to mice. Importantly, cortisone was being metabolised into an as yet unknown compound. Taken together, these results allow a greater understanding of specific regulation of 11β-HSD1 between preadipocytes from different depots. As well, the results in this thesis suggest that in vivo, in addition to effects on adipocyte hypertrophy, 11β-HSD1 expression in preadipocytes influences preadipocyte differentiation and this may be important in determining regional fat distribution.
15
Niesler, Carola Ulrike. « A study of preadipocyte apoptosis in relation to the regulation of adipose tissue mass ». Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624194.
Texte intégral
16
Hirai, Shizuka. « Studies on the regulation of preadipocyte differentiation by paracrine factors secreted from muscle cells ». Kyoto University, 2006. http://hdl.handle.net/2433/78167.
Texte intégralRésumé :
Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第12364号
農博第1545号
新制||農||924(附属図書館)
学位論文||H18||N4122(農学部図書室)
UT51-2006-J356
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 矢野 秀雄, 教授 久米 新一, 教授 今井 裕
学位規則第4条第1項該当
17
Gusinjac, Arjeta. « The role of aortic carboxypeptidase-like protein (ACLP) in 3T3-L1 preadipocyte and adipocyte function ». Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28384.
Texte intégralRésumé :
Aortic carboxypeptidase-like protein (ACLP) is a 175kDa secreted protein that is downregulated with adipogenesis. I engineered 3T3-L1 preadipocytes that overexpressed ACLP protein and sustained the overexpression with differentiation. I assessed the role of sustained ACLP overexpression on 3T3-L1 adipogenesis, with a focus on possible ACLP interaction with collagen-I during differentiation.
ACLP overexpression did not affect 3T3-L1 adipogenesis under standard cell culture conditions ACLP overexpression did not affect subconfluent preadipocyte proliferation, apoptosis in serum-supplemented preadipocytes, or serum-deprived preadipocyte cell death. Sustained ACLP overexpression did not affect collagen I/III protein expression, or the activity of matrix metalloproteinase (MMP)-2 and MMP-9 extracellular degrading enzymes.
However, sustained ACLP overexpression on collagen-I coated dishes inhibited the expression of three key differentiation markers, peroxisome proliferator-activated receptor gamma, CCAAT enhancer-binding protein alpha and fatty acid synthase and decreased insulin-stimulated Akt/protein kinase B phosphorylation. This suggests that a collagen-I-rich environment is necessary for ACLP to alter preadipocyte function.
18
Kuzmochka, Claire. « Investigating the role and regulation of histone deacetylase 1 (HDAC1) in glucocorticoid-potentiated preadipocyte differentiation ». Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28688.
Texte intégralRésumé :
Corticosteroids promote central obesity in humans and enhance the efficiency of preadipocyte differentiation in culture. The glucocorticoid receptor(GR) stimulates preadipocyte differentiation, in part, by enhancing transcription of the adipogenic commitment factor C/EBPalpha. GR is hypothesized to enhance C/ebpalpha transcription through a mechanism that involves promoting the titration, and subsequent degradation, of the co-repressor histone deacetylase 1(HDAC1) from the C/EBPalpha promoter.
The first section of this investigation demonstrates that HDAC1, and not HDAC2 is involved in suppressing GR-potentiated preadipocyte differentiation and that the ability of HDAC1 to inhibit the adipogenic program is dependent on its deacetylase activity. Furthermore, the results imply that additional inhibitors assist HDAC1 in actively suppressing C/ebpalpha transcription in the absence of corticosteroids, as well as indicating that HDAC1 likely has supplementary deacetylation targets at the C/EBPalpha promoter, in addition to K98,101 and 102 of C/EBPbeta. Finally, we demonstrate that D181A HDAC1 is a catalytically compromised, dominant negative mutant of HDAC1.
In the second section of this investigation we provide evidence that, contrary to published results, acetylation of HDAC1 at lysine residues 218, 220, 432, 438, 439 and 441 does not inactivate the deacetylase activity of the enzyme. However, we propose a new hypothesis which reconciles our results with the published findings: Alterations in the acetylation status of the six identified lysine residues of HDAC1 regulate the substrate specificity of the enzyme, rather than its catalytic activity.
19
Aubert, Jérôme. « I. Du preadipocyte a l'adipocyte : voies de signalisation adipogeniques. ii. regulation de l'expression d'une proteine secretee, l'angiotensinogene ». Nice, 1998. http://www.theses.fr/1998NICE5224.
Texte intégralRésumé :
La premiere partie de ce manuscrit detaillera le mecanisme d'action du facteur adipogenique carbacycline (cpgi 2), analogue stable de la prostacycline (pgi 2). La prostacycline, metabolite majeur de l'acide arachidonique chez les preadipocytes et les adipocytes, a ete rapportee par notre laboratoire pour induire la differenciation terminale des preadipocytes en adipocytes par l'intermediaire d'une augmentation intracellulaire d'ampc et de ca 2 +, mise en jeu a la suite de la liaison de ce prostanoide avec son unique recepteur membranaire specifique du stade preadipocytaire (recepteur ip). Notre etude a revele que cpgi 2 pouvait induire l'expression de genes tels que l'angiotensinogene, l'a-fabp ou l'ucp-2, independamment de l'activation de son recepteur membranaire. L'effet transcriptionel induit par cette prostaglandine parait mettre en jeu l'activation de recepteurs nucleaires de la super famille des proliferateurs de peroxysomes (ppars) dont l'activite est determinante pour la mise en route du programme de differenciation. Outre l'elevation du ca 2 + intracellulaire dont les cibles restent a definir, nous venons de demontrer que l'augmentation de l'ampc engendree par l'activation du recepteur ip par son ligand entrainait une induction rapide et importante des genes codant pour les facteurs de transcription c/ebp et c/ebp, facteurs eux aussi impliques dans la mise en route de la differenciation adipocytaire. Ainsi, l'effet adipogenique de la carbacycline semble etre la resultante de l'activation de ces deux voies de signalisation. Dans la seconde partie de notre manuscrit, nous avons montre que la cellule preadipeuse secretait et etait capable de repondre au leukemia inhibitory factor (lif), suggerant que cette cytokine
20
Salem, Abdou Houssein. « Understanding C/EBPbeta LAP/LIP Transcriptional and Adipogenic Potential Through Regulation by HDAC1 and GCN5 ». Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19998.
Texte intégralRésumé :
The CCAAT/Enhancer Binding Protein Beta (C/EBPβ) is part of the leucine zipper family of transcription factors and is involved in a myriad of processes including cellular proliferation and differentiation. C/EBPβ is expressed as three isoforms (LAP*, LAP, LIP), translated from a single mRNA by a leaky ribosomal scanning mechanism. While LAP* and LAP have activating functions, LIP is recognized as being a repressor of transcription due to its lack of activation domains.
Numerous studies have shown that C/EBPβ acetylation state modulates its activity in a promoter-specific manner. For instance, the acetyltransferases GCN5/PCAF and the deacetylase complex mSin3A/HDAC1 regulate C/EBPβ activity on the C/EBPa promoter. GCN5/PCAF-mediated acetylation of C/EBPβ was shown to positively affect its transcriptional activity in a steroid-dependent mechanism via the glucocorticoid receptor (GR). GR relieves HDAC1 association from C/EBPβ by targeting the deacetylase for proteasomal degradation, hence favouring GCN5-mediated acetylation of C/EBPβ and allowing maximum activation capacity to be reached. In order to further elucidate C/EBPβ activation, I sought to characterize the interplay between GCN5 and HDAC1 in regulating C/EBPβ LAP/LIP activity during murine adipogenesis by identifying their binding domain in C/EBPβ.
I identified a minimal domain located within regulatory domain 1 (RD1) of C/EBPβ that is required for both GCN5 and HDAC1 binding. Furthermore, the loss of the identified domain in C/EBPβ appears to partially mimic the GR effect, thus giving C/EBPβ a higher basal transcriptional activity that accelerates NIH 3T3 and 3T3 L1 adipogenesis. Moreover, I also showed that the LIP isoform inhibitory mode of action is partially mediated through the mSin3A/HDAC1 repressor complex, which gives LIP an active repressor function. In addition to LIP inhibitory function, I also showed that a cysteine residue located in LAP* negatively regulates its transactivating function during murine adipogenesis.
Although RD1 of C/EBPβ has been suggested to act as a negative regulatory domain, I showed that only five residues are responsible for most of its inhibitory effect. Hence, in an attempt to further define sub-domains within RD1, I characterized a new positive regulatory domain at its N-terminal region, which seems to be required for C/EBPβ activity in a promoter-specific manner.
In conclusion, this study not only supports previously hypothesized mechanisms by which C/EBPβ is regulated, but it also redefines the contribution of LAP*, LAP and LIP in regulating transcription. Most importantly, the results emphasize the countless possibilities by which C/EBPβ transactivation potential could be modulated during cellular differentiation.
21
Fossoyeux-Comte, Emmanuelle. « Culture de preadipocytes : méthodologie et intérêt ». Bordeaux 2, 1988. http://www.theses.fr/1988BOR2P112.
Texte intégral
22
Wurst, Ulrike [Verfasser], Mathias [Akademischer Betreuer] Faßhauer, Peter [Gutachter] Kovacs et Ralph [Gutachter] Burkhardt. « Die Regulation von Preadipocyte factor-1 bei Gestationsdiabetes mellitus und Präeklampsie / Ulrike Wurst ; Gutachter : Peter Kovacs, Ralph Burkhardt ; Betreuer : Mathias Faßhauer ». Leipzig : Universitätsbibliothek Leipzig, 2016. http://d-nb.info/1240696191/34.
Texte intégral
23
Zewdu, Abeba. « Novel Insights into Dedifferentiated Liposarcoma Pathogenesis : Evaluating the Tumor-Promoting Role of IL6/GP130 Signaling via MDM2 Upregulation ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu15320904714479.
Texte intégral
24
Persdotter, Hedlund Gabriella. « Protein and mRNA Studies of Rat FA1/Pref-1/dlk ». Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7773.
Texte intégral
25
Boeuf, Stéphane. « Comparative study of gene expression during the differentiation of white and brown preadipocytes ». Phd thesis, Universität Potsdam, 2002. http://opus.kobv.de/ubp/volltexte/2005/51/.
Texte intégralRésumé :
EinleitungSäugetiere haben zwei verschiedene Arten von Fettgewebe: das weiße Fettgewebe, welches vorwiegend zur Lipidspeicherung dient, und das braune Fettgewebe, welches sich durch seine Fähigkeit zur zitterfreien Thermogenese auszeichnet. Weiße und braune Adipozyten sind beide mesodermalen Ursprungs. Die Mechanismen, die zur Entwicklung von Vorläuferzellen in den weißen oder braunen Fettzellphenotyp führen, sind jedoch unbekannt. Durch verschiedene experimentelle Ansätze konnte gezeigt werden, daß diese Adipocyten vermutlich durch die Differenzierung zweier Typen unterschiedlicher Vorläuferzellen entstehen: weiße und braune Preadipozyten. Von dieser Hypothese ausgehend, war das Ziel dieser Studie, die Genexpression weißer und brauner Preadipozyten auf Unterschiede systematisch zu analysieren.
Methoden
Die zu vergleichenden Zellen wurden aus primären Zellkulturen weißer und brauner Preadipozyten des dsungarischen Zwerghamsters gewonnen. „Representational Difference Analysis“ wurde angewandt, um potentiell unterschiedlich exprimierte Gene zu isolieren. Die daraus resultierenden cDNA Fragmente von Kandidatengenen wurden mit Hilfe der Microarraytechnik untersucht. Die Expression dieser Gene wurde in braunen und weißen Fettzellen in verschiedenen Differenzierungsstadien und in braunem und weißem Fettgewebe verglichen.
Ergebnisse
12 Gene, die in braunen und weißen Preadipozyten unterschiedlich exprimiert werden, konnten identifiziert werden. Drei Komplement Faktoren und eine Fettsäuren Desaturase werden in weißen Preadipozyten höher exprimiert; drei Struktur Gene (Fibronectin, Metargidin und a Actinin 4), drei Gene verbunden mit transkriptioneller Regulation (Necdin, Vigilin und das „small nuclear ribonucleoprotein polypeptide A“) sowie zwei Gene unbekannter Funktion werden in braunen Preadipozyten höher exprimiert. Mittels Clusteranalyse (oder Gruppenanalyse) wurden die gesamten Genexpressionsdaten charakterisiert. Dabei konnten die Gene in 4 typischen Expressionsmuster aufgeteilt werden: in weißen Preadipozyten höher exprimierte Gene, in braunen Preadipozyten höher exprimierte Gene, während der Differenzierung herunter regulierte Gene und während der Differenzierung hoch regulierte Gene.
Schlußfolgerungen
In dieser Studie konnte gezeigt werden, daß weiße und braune Preadipozyten aufgrund der Expression verschiedener Gene unterschieden werden können. Es wurden mehrere Kandidatengene zur Bestimmung weißer und brauner Preadipozyten identifiziert. Außerdem geht aus den Genexpressionsdaten hervor, daß funktionell unterschiedliche Gruppen von Genen eine wichtige Rolle bei der Differenzierung von weißen und braunen Preadipozyten spielen könnten, wie z.B. Gene des Komplementsystems und der extrazellulären Matrix.
Introduction
Mammals have two types of adipose tissue: the lipid storing white adipose tissue and the brown adipose tissue characterised by its capacity for non-shivering thermogenesis. White and brown adipocytes have the same origin in mesodermal stem cells. Yet nothing is known so far about the commitment of precursor cells to the white and brown adipose lineage. Several experimental approaches indicate that they originate from the differentiation of two distinct types of precursor cells, white and brown preadipocytes. Based on this hypothesis, the aim of this study was to analyse the gene expression of white and brown preadipocytes in a systematic approach.
Experimental approach
The white and brown preadipocytes to compare were obtained from primary cell cultures of preadipocytes from the Djungarian dwarf hamster. Representational difference analysis was used to isolate genes potentially differentially expressed between the two cell types. The thus obtained cDNA libraries were spotted on microarrays for a large scale gene expression analysis in cultured preadipocytes and adipocytes and in tissue samples.
Results
4 genes with higher expression in white preadipocytes (3 members of the complement system and a fatty acid desaturase) and 8 with higher expression in brown preadipocytes were identified. From the latter 3 coded for structural proteins (fibronectin, metargidin and a actinin 4), 3 for proteins involved in transcriptional regulation (necdin, vigilin and the small nuclear ribonucleoprotein polypeptide A) and 2 are of unknown function. Cluster analysis was applied to the gene expression data in order to characterise them and led to the identification of four major typical expression profiles: genes up-regulated during differentiation, genes down-regulated during differentiation, genes higher expressed in white preadipocytes and genes higher expressed in brown preadipocytes.
Conclusion
This study shows that white and brown preadipocytes can be distinguished by different expression levels of several genes. These results draw attention to interesting candidate genes for the determination of white and brown preadipocytes (necdin, vigilin and others) and furthermore indicate that potential importance of several functional groups in the differentiation of white and brown preadipocytes, mainly the complement system and extracellular matrix.
26
Landron, Dorothée. « Interactions de l'hormone de croissance humaine avec les adipocytes de rats zucker genetiquement obeses : relations entre la liaison et les effets biologiques ». Paris 6, 1988. http://www.theses.fr/1988PA066344.
Texte intégralRésumé :
L'objectif de ce travail est de comparer la liaison et les effets biologiques de l'hormone de croissance (gh) 1) dans les adipocytes du tissu inguinal de jeunes rats zucker obeses fa/fa et minces fa/fa; 2) dans les preadipocytes de rats zucker en culture primaire au cours de la differenciation adipocytaire. 1. Les etudes de liaison de la gh et les courbes dose-reponse pour le transport et le metabolisme du glucose sont realisees avec des adipocytes soit fraichement isoles (f) soit preincubes 3 h (p)
27
corno, chiara. « Studio degli effetti del trattamento con INT-767 sulla capacità differenziativa dei preadipociti ». Doctoral thesis, 2019. http://hdl.handle.net/2158/1151891.
Texte intégralRésumé :
La sindrome metabolica (SM) è una patologia caratterizzata da un insieme di fattori di rischio cardio-metabolici. Un
ruolo centrale nella patogenesi è svolto dall'obesità vlscerale e dall'insulino-resistenza che causano, a livello epatico, il
manifestarsi della steatoepatite non alcolica (NASH). Nella SM gli adipociti gravemente disfunzionanti, perdendo la
capacità di rispondere all'insulina, diventano incapaci di sostenere l'aumento dell'apporto energetico. Questo
determina ipertrofia e iperplasia del tessuto adiposo, che inlzia a rilasciare in circolo citochine pro-infiammatorie che
vanno ad alterare la funzionalità degli organi periferici, come ad esempio fegato. ll recettore X del farnesoide (FXR) e il
recettore accoppiato a proteina G (TGR5), entrambi recettori degli acidi biliari, regolano diversi pathway, tra cui il
metabolismo glicidico e lipidico. ln un modello di coniglio di sindrome metabolica indotta da una dieta ricca di grassi
(HFD), il trattamento a lungo termine con INT-767 doppio agonista FXR/TGRs riduce l'accumulo del tessuto adiposo
viscerale, l'iperglicemia, l'ipercolesterolemia e la steatoepatite non alcolica. INT-767 mostra avere un effetto diretto
sulla differenziazione dei preadipociti (rPAD), migliorando il quadro metabolico, principalmente attraverso un
aumento della sensibilità all'insulina dipendente da FXR, e migliorando la funzione mitocondriale e la differenziazione
bruna, dipendenti da TGR5. Nei preadipociti, INT-767 si comporta principalmente come agonista TGR5, attivando
direttamente in modo dose-dipendente la via cAMP/PKA. I preadipociti isolati dal tessuto adiposo viscerale (VAT) di
conigli trattati con INT-767, rispetto ai preadipociti di HFD, mostrano una maggiore espressione dell'mRNA dei
marcatori di adipogenesi bruna (BMP4, CIDEA, HOXC9, LHX8, TMEM26), della biogenesi e motilità mitocondriale (FlS1,
NRF1, TFAM), del signaling del cGMP (GCSA1, GCSBL, PKGl). Questi dati sono stati confermati dall'analisi
dell'espressione genica su omogenati di VAT isolati da animali HFD trattati con INT-767. Nel VAT si osserva un
aumento dei geni relativi alla sopravvivenza (BLC-2), all'adipogenesi bruna (ClDEA, LHX8, PKG1, UCPl), alla
mitocondriogenesi (NRF1, PGC1A, TFAM), al signaling dell'insulina (STAMP2), al metabolismo lipidico (PPARa) e il
rimodellamento delle goccioline lipidiche (PLlN1, STX5, VAMP4). ll trattamento in vivo contrasta, inoltre, le alterazioni
mitocondriali negli rPAD, ne migliora la lunghezza e la dinamicità, promuovendo il processo di fissione e fusione
mitocondriale. INT-767 in vivo riduce la produzione di superossido, la sintesl di ATP, e aumenta il consumo di ossigeno.
Questi miglioramenti della funzionalità mitocondriale sono associati all'aumentata espressione di UCP1, indotta
dall'tNT-767, osservata in campioni omogenati di VAT, isolati da animali trattati in vivo. Anche il rimodellamento delle
goccioline lipidiche risulta nettamente migliorato dal trattamento in vivo.lnfine, INT-767 ha mostrato la capacità di
ridurre le alterazioni istologiche epatiche indotte dalla dieta HFD e di normalizzare l'aumentata espressione dei geni
pro-infiammatori (112, lL6, TNFo). INT-767 induce anche una significativa riduzione dell'espressione genica dei marker
di fibrosi (SNAl2) e di sintesi degli acldi grassi (ACC1, FAS), viceversa aumentando contestualmente l'espressione di
marker legati al corretto immagazzinamento dei lipidi (ABCA1, PLlN1, SNAP23, SRB1, STX5, VAMP4), alla segnalazione
insulinica (lRS1, STAMP2) e dei marcatori mitocondriali (FlS1, MFNL, MFN2, OPA1, SDHB, SLC25A12). ln conclusione,
INT-767 contrasta significativamente le alterazioni indotte da HFD osservate nel fegato e nel grasso, ripristinando la
sensibilità all'insulina e la differenziazione dei preadipociti verso un fenotipo metabolicamente sano.
28
FACCHIANO, ENRICO. « Effetti del trattamento sostitutivo con testosterone sulla disfunzione del tessuto adiposo e sull’epatopatia steatosica non alcolica (NAFLD) nel paziente obeso di sesso maschile candidato a chirurgia bariatrica ». Doctoral thesis, 2017. http://hdl.handle.net/2158/1077224.
Texte intégralRésumé :
Lo scopo del presente studio è quello di analizzare gli effetti del testosterone sulla disfunzione del tessuto adiposo e sulla NAFLD nei pazienti obesi di sesso maschile candidati a chirurgia bariatrica, comparando i pazienti sottoposti a terapia sostitutiva con testosterone (TRT) con i pazienti ipogonadici non trattati e con quelli eugonadici.
29
Chen, Chu-liang 1961. « Regulation of 3T3-L1 preadipocyte differentiation in culture ». Thesis, 1996. http://hdl.handle.net/1957/34190.
Texte intégral
30
Tian, Zi-Han, et 田子函. « Betel nut alkaloids regulate 3T3-L1 preadipocyte growth ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/a3ed7z.
Texte intégralRésumé :
碩士國立中央大學
生命科學系
103
Betel nut is one of the common substances consumed in Asia, and betel nut alkaloids (BNAs), especially arecoline, are found to be present in the saliva of areca nut chewers. Although arecoline has been shown to regulate glucose uptake and adipogenesis in 3T3-L1 adipocytes, little information is known about the action of arecoline on growth of preadipocytes. Using 3T3-L1 preadipocytes, we observed that arecoline, but not other structurally related alkaloids, such as arecaidine or guvacine, reduced cell viability of 3T3-L1 preadipocytes in dose- and time-dependent manners. Flow cytometric analysis of the cell cycle indicated that exposure to arecoline, but not arecaidine or guvacine, for 24 and 48 h decreased the cell population in G1 stage and increased the cell population in S stage and the G2/M stage of 3T3-L1 preadipocytes. Further Western blot analysis showed that arecoline at 24 h reduced levels of the G1 checkpoint-stimulating proteins, such as p21, p27 and AMP-activated protein kinase (AMPK), decreased levels of the G2 checkpoint-controlling protein, such as CDK1, increased cyclin B1 and p53 protein level, and unaltered CDK2 protein level. Interestingly, arecaidine and guvacine altered p21 and p53 protein levels and unaltered p27, CDK1, CDK2, and cyclin B1 protein levels. Pretreatment with N-acetyl-cysteine (NAC), a glutathione activator, suppressed the arecoline-induced decreases in levels of cell viability and G1 phase of the cell cycle. Moreover, NAC blocked the arecoline-increased percentages of S and G2/M stages of the cell cycle and levels of reactive oxygen species (ROS) production. In addition, NAC prevented the arecoline-decreased levels of p21, p27, CDK1 and AMPK proteins and the arecoline-increased levels of p53 and cyclin B1. However the muscarinic acetylcholine receptor (mAChR) antagonist, such as atropine, did not block the arecoline-reduced cell viability but enhanced further arecoline-stimulated ROS production. Neither GABA nor its type B receptor antagonist, such as saclofen, blocked arecoline-suppressed cell viability. In conclusion, arecoline is the selective ingredient from BNAs to inhibit 3T3-L1 preadipocyte growth through alterations of the cell cycle possibly in p53-, p21-, p27-, CDK1-, cyclin B1, AMPK- and ROS-dependent pathways and GABA B receptor- and mAChR-independent pathways.
31
Wagoner, Courtney Blair. « Direct and indirect effects of leptin on preadipocyte development ». 2005. http://purl.galileo.usg.edu/uga%5Fetd/wagoner%5Fcourtney%5Fb%5F200512%5Fms.
Texte intégral
32
Li, Yi-Jun, et 李奕均. « Establishment of an immortalized porcine preadipocyte clone and adipocyte differentiation ». Thesis, 2007. http://ndltd.ncl.edu.tw/handle/24906516760697659248.
Texte intégralRésumé :
碩士國立臺灣大學
動物科學技術學研究所
95
Culture of animal cells is a basic and important technique for research and development of biotechnological products. It is used to investigate cell physiology, proliferation, differentiation, and function of genes and regulation of their expression. Originally, scientists employ primary cell culture for research but primary cultured cells will be senescent or die after multiple passages. For this reason, they have to isolate new cells from tissues for each experiment. Not only greater cost of time and money is needed but also the result of experiment will vary due to the differences among batches of cells. As a result, a stable clone is essential for better research. The aim of our study was to establish an immortalized pig preadipocyte by introduction of a combination of telomerase and human papillomavirus type 16 E7 (HPV 16-E7). The primary porcine stromal vascular cells were isolated from back fat of a two-week hybrid pig (Landrace, Yorkshire, and Duroc). Retrovirus with human telomere reverse transcriptase (hTERT) or HPV 16-E7 were produced by GP2-293 packaging cell line. Retrovirus with hTERT infected primary cells at passage one and then, cells were selected by puromycin for two weeks. The cells that were alive after treatment of puromycin, indicating a successful expression of telomerase. We also confirmed that the telomerase mRNA was present in the selected cells. They were infected with HPV 16-E7 containing retrovirus, and selected by histidinol treatments. After histidinol selection, pure cell strains were obtained by cell cloning. The expression of hTERT and HPV 16-E7 mRNA in several clones of porcine preadipocyte were confirmed by RT-PCR. One of the clones grew very fast and could be induced to differentiate into adipocyte when treated with adipocyte differentiation medium (insulin, dexamethasone, rosiglitazone, containing DMEM/F12). We named this cell clone LYD1. Expression of preadipocyte factor 1 (pref-1), peroxisome proliferator activated-receptor gamma (PPARγ）, lipoprotein lipase（LPL） and adipocyte-specific fatty acid binding protein（aP2） were determined. Because LYD1 cells can express hTERT and HPV 16-E7 genes, we conjecture that LYD1 cells can proliferate indefinitely. These LYD1 cells could be induced to differentiate into adipocyte by differentiation medium. Therefore, if we can confirm the expression of adipocyte specific gene, it will become a suitable porcine preadipocyte clonal cell line.
33
Yeh, Yi-Chun, et 葉怡均. « Effects of conjugated linoleic acid on the differentiation of preadipocyte ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/48315882702442369415.
Texte intégralRésumé :
碩士國立臺灣海洋大學
食品科學系
92
Conjugated linoleic acid (CLA) is a collective term for positional and geometric isomers of linoleic acid. CLA occurs naturally in a variety of foods, particularly dairy products and meat from ruminant animals. CLA has been clearly shown to have a number of biological actions: it inhibits carcinogenesis and atherosclerosis; enhanced immune responses, and reduced body fat etc. The objective of this study was to determine the effects of c-9, t-11 and t-10, c-12 isomers of CLA on the differentiation of mouse 3T3-L1 preadipocytes and the production of some cytokines. c-9, t-11 CLA and t-10, c-12 CLA at concentration above 50 μg/L can inhibit the growth of 3T3-L1 preadipocytes. By using DNA fragmentation, cell cycle analysis and Annexin V-FITC/PI assay, showed that CLA can induced preadipocytes apoptosis. On the differentiation of preadipocyte, 3T3-L1 preadipocytes were cultured until confluence, and cells were induced using the differentiation reagents, confluence 3-isobutyl-methylxanthine / Dexamethasone / Insulin (MDI), eight days after the cells were induced for differentiation, by Oil Red O-stained, we found that CLA prevents triacylglycerol accumulation. t-10, c-12 CLA (25 μg/L) showed a 45 % of decreased triglyceride production, and c-9, t-11 CLA (25 μg/L) presented a 25 % of that. Furthermore, we also evaluated the effects of c-9, t-11 and t-10, c-12 isomers of CLA on the expression of C/EBPα, PPARγ and SREBP-1, which are transcriptional factors essential for adipocytes differentiation and lipogenesis, using the RT-PCR technique. Results showed that t-10, c-12 CLA at concentration above 25 μg/L significantly decreased the mRNA expression of C/EBPα, PPARγ and SREBP-1 by 53, 62 and 60 %, respectively. This inhibitory effect was dose-dependent. And c-9, t-11 CLA at concentration above 25 μg/L also decreased the mRNA expression of C/EBPα and PPARγ by 20 %. However, c-9, t-11 CLA presents no inhibition on the expression of SREBP-1. The other evidence is presented indicating that CLA may modulate cellular response to TNF-α and CRP. These results suggest that CLA can induced preadipocytes apoptosis, inhibit adipogenesis and differentiation through suppressing the associated transcription factors, C/EBPα, PPARγ and SREBP-1. Furthermore, CLA may inhibit 3T3-L1 cell differentiation by interfering with the cytokine regulated pathway.
34
Casimir, David Alan. « Regulation of early preadipocyte differentiation cAMP and prostaglandin F₂[alpha] / ». 1996. http://catalog.hathitrust.org/api/volumes/oclc/36569652.html.
Texte intégralRésumé :
Thesis (Ph. D.)--University of Wisconsin--Madison, 1996.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (lweaves 133-145).
35
Wang, Hsiao-Hsien, et 王孝賢. « The Effect of Various Functional Food Formulas for Differentiation of Preadipocyte ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/85305336574449117574.
Texte intégralRésumé :
碩士中原大學
生物科技研究所
100
The metabolic syndrome is a cluster of interrelated abnormalities which include obesity, insulin resistance, dyslipidemia and hypertension. People with metabolic syndrome are highly at risk for developing type 2 diabetes and cardiovascular diseases. The principal risk factors involved in the development of metabolic syndrome are obesity and insulin resistance. Obesity is defined as a state of pathological hyperplasia and/or hypertrophy of adipose tissue. Insulin resistance is defined as a decreased sensitivity of target cells to insulin-stimulated glucose transport. Moreover, adipocyte secret numerous adipocytokines, such as adiponectin, TNF-α, leptin, and resistin, which can affect systemic metabolism and consequentially cause insulin resistance. Functional food refer to processed food which claim to have health-promoting or disease-preventing properties beyond the basic function of supplying nutrients. Therefore, development of anti - obesity functional food is a good strategy against obesity and obesity-related metabolic syndrome. Several studies have focused on developing different food ingredient aimed at combating partial disorders. However, it is not easy to fully counteract the development of multi-factorial metabolic syndrome. Development of multi-component functional foods may be a better preventive and intervention strategy to combat the burden of metabolic syndrome. In our study, each functional food ingredient, such as roselle, chlorella, cinnamon, and bitter gourd, was taken as a potential candidate to ameliorate the development of insulin resistance, obesity, dyslipidemia, and hypertension, separately. The cells were isolated from the stromal vascular fraction of both subcutaneous and perirenal- fat depots, and the subset was cultured with two differentiation cocktails. Then, we analyzed the relationship between the degree of preadipocyte differentiation and metabolic factors. Furthermore, relative low-dose combination of these single ingredients showed better preventive effects than each ingredient test individually. In conclusion, with multiple ingredients could serve as a nutraceutical to prevent the development of obesity and obesity-related metabolic syndrome.
36
Peng, Kang Yu, et 彭康祐. « The effect of Resveratrol on Preadipocyte Differentiation and Mice Body Weight Regulation ». Thesis, 2010. http://ndltd.ncl.edu.tw/handle/98560543128776697009.
Texte intégralRésumé :
碩士長庚大學
中醫學系天然藥物
98
Obesity along with its complaints is considered serious global health problems. Most of the anti-obese drugs currently in use are either unsatisfying or with severe side effects. The body weight regulating effect of resveratrol (RSV) has been reported in several independent studies, however the underlying mechanisms are still poorly understood. With both in vitro and in vivo methods, we examined the effect of RSV, focusing mainly on the changes of white adipocytes differentiation and lipid accumulation. To our surprise, a biphasic effect of RSV on 3T3-L1 differentiation was observed. At lower concentration, RSV could directly stimulated cellular differentiation. At higher concentration, however, RSV strongly suppressed MDI-induced preadipocytes differentiation. In vivo experiment suggested that oral administration of 5 mg/kg/day RSV for 10 weeks result in body weight increase in high-fat-diet mice model, which could be correlated with the stimulatory effect of RSV on preadipocytes differentiation in vitro. Taken together, our study provided new insights into the potential bodyweight regulating effect of RSV.
37
Wang, Sheue-Chi, et 王雪其. « Effects of Essential Oils on the Differentiation Process of 3T3-L1 Preadipocyte Cells ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/62428140272528450823.
Texte intégralRésumé :
碩士國立陽明大學
生物化學研究所
92
Obesity is becoming a world wide epidemic. It is considered a disease not only because of the stigma of being fat, but also because of the chronic diseases associated with it. Aromatherapy, which is a form of alternative therapy, is becoming a more and more widely chosen treatment for obesity, yet the mechanisms behind their effects are mostly still unknown. Oleaceae oil is the aromatic constituent of a flower from the Oleaceae family obtained through solvent extraction methods. The aim of this experiment is to examine the effects of Oleaceae oil on preadipocyte differentiation and the identification of its active components. When induced to differentiate in the presence of Oleaceae oil (35-130 mg/ml), 3T3-L1 preadipocytes dose- dependently reduced their ability to accumulate cellular triglycerides. Cytoplasmic triglyceride droplets could also be visualized by microscopic observation. Cells treated with 130 mg/ml Oleaceae oil retained their morphology as spindly fibroblasts, while normal adipocytes take on a rounded shape filled with triglyceride droplets. Fractions separated by silica gel chromatography were subjected to the same assay and the active fraction was subsequently analyzed by GS/ MS. Results show that the main component of the active fraction is most likely to be ethyl linoleate. A purer compound needs to be obtained to verify its chemical structure.
38
Wei-Lun, He, et 何瑋倫. « Effects of Extracted Oil Fractions from Porphyra crispata on 3T3-L1 Preadipocyte Differentiation ». Thesis, 2008. http://ndltd.ncl.edu.tw/handle/78092678330136758313.
Texte intégralRésumé :
碩士國立臺灣海洋大學
食品科學系
96
Obesity is a major risk factor for diabetes, hyperlipidemia, hypertension, cardiovascular diseases, and metabolic syndrome. Omega-3 polyunsaturated fatty acid (PUFA) of marine origin predicted to regulated lipid metabolism and antioxidants could reduced the oxidative stress which induced by obesity. We extracts the oil from Porphyra crispate, a kind of Rhodophyta, by methanol/chloroform, there is 30.4% eicosapentaenoic acid (EPA) of the fatty acids. We also determine the content of antioxidants in otal extract (PCO) and fractions. There were 0.56~1.82% total phenolic content, 0.22~21.67 �慊/mL chlorophyll a,0.37~13.37�慊/mL chlorophyll b and 1.11~130.06�慊/mL carotenoid in PCO and fractions. PCO and fractions also had total antioxidant activity 89.95~771.08 (�慊 trolox equivalents/g extract) and 10.62~41.38% DPPH radical scavenging activity. In this report, we investigated the effects of ethanol extract of PCO ( Et- PCO), methyl esterification (PCF) and nonsaponifiable (PCS) on the 3T3-L1 differentiation. Et-PCO was no significantly effect on cell differentiation. PCS and PCF could promoted cell differentiation and triglyceride accumulation in dose dependent, especially treated at Day 0. On the other hand, PCS was increasing the content of cholesterol in 3T3-L1. PCF could induced PGC-1 mRNA expression. Furthermore, PCS and PCF could reduce the ROS production. Our results suggest that antioxidant of PCO may prevent the obesity-associated metabolic syndrome and PCF and PCS may decrease hyperlipidemia by promoting triglyceride accumulation.
39
Tsai, Jung-Wei, et 蔡鎔薇. « The Effect of Acorus calamus Essential Oil on 3T3-L1 Preadipocyte Cells Differentiation ». Thesis, 2006. http://ndltd.ncl.edu.tw/handle/59573532968329041757.
Texte intégralRésumé :
碩士國立陽明大學
生化暨分子生物研究所
94
Obesity is becoming a world wide epidemic. It is considered a disease not only because of the stigma of being fat, but also because of the chronic diseases associated with it. Aromatherapy, which is a form of alternative therapy, is becoming a more and more widely chosen treatment for obesity, yet the mechanisms behind their effects are mostly still unknown. In this study, we tried to find the essential oils owing anti-obesity effects by utilizing scientific methods. 3T3-L1 preadipocytes were chosen as the cell model, and the level of triglyceride accumulation was used to estimate the differential extent of these cells. Plant essential oils showed the anti-differentiation activity and then proceeded further separation and purification for the effective compounds. After the anti-differentiation activity was analyzed, the active component was confirmed as the effective compound of plant essential oil. Compare to the control group, the triglyceride level of the adipocytes was lowered to 47% under the 0.25 mM the active component treatment. The active component also decreased the expression of PPARγ �nand C/EBPα. These results suggested that the effective compound of plant essential oil, the active component can inhibit the differentiation of 3T3-L1 preadipocytes and the inhibitory activity, in part, dependent on the down-regulation of PPARγ �nand C/EBPα.
40
Huang, Jhengyu, et 黃政猷. « Comparative Studies in Preadipocyte Differentiation between Taiwan Country Chickens with Different Egg Productions ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/58527001867894049532.
Texte intégralRésumé :
碩士東海大學
畜產與生物科技學系
100
Egg production is an energy-intensive process in chickens. Adipose tissues are known to regulate energy balance in animals. Therefore, development of adipose tissues may play roles in animal proliferation and reproduction. Two selected lines of Taiwan country chickens originated from a common population with relatively high (L2 line) and low (B line) egg yields were used in a previous study that indicated the correlation between laying performance and the differentiation capacity, triglyceride accumulation, and lipolysis activity of adipocytes. This study aimed to further investigate the possible correlation between preadipocyte differentiation and egg production efficiency within L2 line chickens. The L2 chickens were divided into high (108.7±0.5) and low (71.3±0.5) egg production groups according to their egg productions at age of 40 weeks. Preadipocytes collected from abdominal adipose tissues were cultured and induced to differentiate. Oil-Red O staining, triglyceride content and glycerol-3-phosphate dehydrogenase (GPDH) activity assays were performed on day 6 after the induction of differentiation. The results of oil-Red O staining, triglyceride content and GPDH activity assays showed that no significant differences between adiopocytes from chickens with high and low egg productions. The mRNA expression of adipocyte differentiation- related genes were measured using real-time polymerase chain reaction. The results revealed that the lipoprotein lipase (LPL) mRNA level was higher in high egg production than those in low egg production group. However, no significant differences in the mRNA levels of peroxisome proliferator-activated receptorγ (PPARγ, fatty acid synthase (FAS), stearoyl CoA desaturase (SCD), sterol regulatory element binding protein1 (SREBP1), adiponectin, very low density lipoprotein receptor (VLDLR), perilipin, and vimentin were found between these two groups. Taken together, differentiation capacity of preadipocytes may not relate to egg productions in L2 line chickens. However the significance of LPL expression difference between L2 chickens with high and low egg productions required further study.
41
Chen, Yun-Ting, et 陳韻婷. « Andrographolide Inhibits 3T3-L1 Preadipocyte Differentiation and Up -regulates Glucose Transporter 4 Expression ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/673upn.
Texte intégralRésumé :
碩士中國醫藥大學
營養學系碩士班
102
Eight of the top ten causes of death in Taiwan are associated with obesity, which has been known as a major risk factor for heart disease, hypertension, diabetes, gout, and cancer. Andrographis paniculata is a popular Chinese herbal medicine. Andrographolide (AND), a diterpenoid, is one of its main active ingredients. A. paniculata displays various physiological functions including anti-tumorigenic, anti-inflammatory, hepatoprotection, hypotension, and anti-microbial activities. To date, the anti-adipogenic and hypoglycemic activity of AND in adipocytes has not been clearly elucidated. Here, we investigated whether AND inhibits adipogenesis and lipogenesis and improves glucose uptake in adipocytes. Oil-O staining indicated that, after a 8-d treatment, AND dose-dependently (0-15 μM ) inhibits lipid accumulation in 3T3-L1 preadipocytes. The inhibitory action of AND was largely limited to the first 48 h of adipocyte differentiation. Moreover, AND impaired the progression of mitotic clonal expansion (MCE) process as evidenced by impaired proliferation and cell-cycle arresting at the S phase. In addition, AND significantly inhibited CCAAT/enhancer binding proteinα/β (CEBPα, β) and peroxisome proliferator-activated receptor γ (PPARγ) expression and, thus, the fatty acid synthase gene expression. On matured 3T3-L1 adipocytes, AND up-regulated glucose transporter 4 (GLUT4) expression and increased 2-[N-(7-nitrobene-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-D-glucose (2-NBDG) uptake. Taken together, these results indicate that the antiadipogenic effect of AND is likely through inhibition of the MCE and reduction of C/EBPα/β and PPARγ expression. Moreover, AND improves glucose uptake by up-regulating GLUT4 expression.
42
Hong, Pei-Fang, et 洪珮芳. « Green tea catechins inhibit 3T3-L1 preadipocyte growth via mitogen-activated protein kinase-associated pathway ». Thesis, 2004. http://ndltd.ncl.edu.tw/handle/44141848627582739711.
Texte intégralRésumé :
碩士國立中央大學
生命科學研究所
92
Obesity, a common disease resulting from mitogenesis and lipid accumulation of fat cells, increases the risks of cancers, diabetes, hypertension, and cardiovascular disease. Based on a variety of laboratory studies, green tea polyphenols, especially the catechin, (-)-epigallocatechin gallate (EGCG), have been proposed as an obesity and other disease chemopreventative. But the exact mechanisms of their action on fat cell mitogenesis are still unclear. Chapter one showed that green tea EGCG could reduce fetal bovine serum-induced mitogenesis of 3T3-L1 preadipocytes through inhibiting the activities of MEK and its downstream cyclin-dependent kinase 2. Chapter two demonstrated that EGCG could stop insulin-like growth factor II (IGF-II)-induced mitogenesis of preadipocytes probably via reducing the IGF-II-stimulated the association of IGF-II receptor with Gi-2 protein and their downstream MEK activity. These results of this thesis provide a mechanism by which EGCG modulates the body weight in various animal models of obesity.
43
Kaválková, Petra. « Význam endokrinní funkce tukové tkáně při vzniku syndromu inzulínové rezistence ». Doctoral thesis, 2016. http://www.nusl.cz/ntk/nusl-353567.
Texte intégralRésumé :
(AJ) Adipose tissue produces numerous adipokines, pro- and antiinflammatory cytokines and hormones which may influence the development of insulin resistance, type 2 diabetes mellitus and other comorbidities of the metabolic syndrome. The ability of adipose tissue to store lipids and thus protect other organs and tissues from ectopic lipid accumulation and development of insulin resistance (IR) is largely dependent on the adipogenic potential of preadipocytes. The amount and function of these cells may be the key factor in creating "healthy" adipose tissue or on the contrary "unhealthy" adipose tissue eventually leading to metabolic derangements. The regulation of the amount of body fat by converting preadipocytes into mature adipocytes may be crucial in the prevention and treatment of obesity and its comorbidities. One of the reasons for development of insulin resistance can be the inhibition of the differentiation process of preadipocytes into mature adipocytes with consequent ectopic lipid accumulation caused by the secretion of preadipocyte factor - 1 (Pref - 1). Pref - 1 has been discovered recently as a protein produced by preadipocytes but not by mature adipocytes. Pref - 1 is a member of the protein family sharing similarity with epidermal growth factors which regulate the differentiation of...
44
沈秀清. « Effects of magnolol on lipolysis of sterol ester-induced 3T3-L1 preadipocyte : morphological and biochemical studies ». Thesis, 2001. http://ndltd.ncl.edu.tw/handle/30343239327477560119.
Texte intégral
45
Lai, Peng-Yeh, et 賴芃燁. « The Opposite Role of Notch2 and Notch4 on The Proliferation And Differentiation of 3T3-L1 Preadipocyte Cells ». Thesis, 2014. http://ndltd.ncl.edu.tw/handle/jdzv36.
Texte intégralRésumé :
博士國立中正大學
分子生物研究所
102
Obesity is an energy balance disorder in the modern world which resulting in excessive white adipose tissue accumulation. Adipose tissue is composed of adipocytes, which differentiates from precursor cells in a process called adipogenesis. Many signal molecules are involved in transcriptional control of adipogenesis, including the Notch pathway. Previous adipogenic studies of Notch have focused on Notch1 and HES1; however, the role of other Notch receptors in adipogenesis remains unclear. Q-RT-PCR analyses showed that the augmentation of Notch4 expression during the differentiation of 3T3-L1 preadipocytes was comparable to that of Notch1. Furthermore, Notch2 expression level was increased significantly in the early differentiation day. To elucidate the role of Notch2 and Notch4 in adipogenesis, the human active form Notch2 (N2IC) and Notch4 (N4IC) were transiently transfected into 3T3-L1 cells. The expression of Notch downstream genes, HES1 and Hey1 and proadipogenic genes, C/EBPδ and PPARγ, were upregulated in N4IC-transfected cells and the expression of Pref-1, an adipogenic inhibitor, was downregulated. To further characterize the effects of N2IC and N4IC in adipogenesis, stable 3T3-L1 cell lines expressing human N2IC or N4IC were established. The expression of N2IC suppressed proliferation and differentiation of 3T3-L1 cells. On the other hand, expression of N4IC promoted proliferation and enhanced differentiation of 3T3-L1 cells compared with those of control cells. Cell cycle and gene expression analyses showed that N2IC suppressed proliferation through cell cycle regulation and suppressed differentiation through downregulating electron transport genes. However, N4IC promoted proliferation through modulating the ERK pathway and the cell cycle during the early stage of 3T3-L1 adipogenesis and facilitated differentiation through upregulating cholesterol biosynthesis genes and adipogenic genes such as C/EBPα, PPARγ, aP2, LPL and HSL during the middle and late stage of 3T3-L1 adipogenesis.
46
Shen, Tsai-Ying, et 沈采螢. « Assessment and Product Development of Seaweed Extracts on Antioxidant Activities and Lipid Accumulation in 3T3-L1 Preadipocyte ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/8gw973.
Texte intégral
47
Hsieh, Hsin-Hui, et 謝欣蕙. « Phosphorylation of Tristetraprolin (TTP) by the ERK Signaling Pathway in the Early Differentiation of 3T3-L1 Preadipocyte ». Thesis, 2015. http://ndltd.ncl.edu.tw/handle/70930351818092261525.
Texte intégralRésumé :
碩士國立臺灣大學
生化科學研究所
103
Previously, our lab has demonstrated that both tristetraprolin (TTP) and MKP-1 are immediate early genes, whose expression were activated and quickly subsided in response to ERK signaling during 3T3-L1 differentiation. Notably, TTP is known as an mRNA-destabilizing protein, which can bind to AU-rich elements (AREs) in the 3’UTR of mRNA and trigger mRNA destabilization. We also found the mRNA target of TTP includes MKP-1 and TTP itself. The function of TTP is tightly regulated by its protein phosphorylation status. The ERK signaling inhibitors U0126 decreased the expression and phosphorylation levels of TTP, indicating that TTP phosphorylation and its function are regulated by ERK signaling. Therefore, this thesis aims to explore the detailed mechanism of how TTP function is regulated by ERK signaling during adipogenesis. Here, we demonstrates that Cnot1, a scaffold protein of Ccr4–Not deadenylase complex, is an essential partner in TTP-mediated mRNA decay by functional luciferase reporter analysis combining with siRNA knockdown and protein-protein interactions analysis. Also, our results reveal that ERK can phosphorylate TTP at serine 220 and increases interaction between TTP with 14-3-3, thus impairing TTP-mediated mRNA decay. Moreover, using mass spectrometry analysis, functional reporter assay and co-immunoprecipitation assay combined with mutants, we demonstrated that TTP was phosphorylated at serine 316 in C-terminal conserved region by ERK signaling, which significantly perturbs Ccr4-Not complex recruitment and TTP mRNA-destabilizing activity. These findings provide a better understanding of how TTP regulate MKP-1 mRNA stability under the control of ERK signaling pathway during 3T3-L1 differentiation.
48
Chang, Yeong-Chang, et 張永昌. « Ubiquitous transcriptional factor, YY-1 ,can recognize PRE( preadipocyte repressor element) of SCD2(Stearoyl CoA desaturase 2) gene ». Thesis, 1993. http://ndltd.ncl.edu.tw/handle/45102922272711961077.
Texte intégralRésumé :
碩士國立臺灣大學
生化科學研究所
81
SCD2(Stearoyl CoA desaturase 2)的負調節序列PRE(Preadipocyte repressor element)的序列和一普遍存在之核內因子YY-1的結合序列甚為 相似,YY-1對轉錄的調控有時扮演促進子的角色,有時則扮演抑制子的角 色 ,端視所涉及的基因以及結合序列而定。目前已經四個不同實驗室分別 在研究不同基因的啟動區而找到相同的蛋白質,也就是YY-1,首先是Shenk 等人發現YY-1可以結合到adeno-associa ted P5這個病毒的啟動區以及起 動區上面,而且當在一般狀況之下,對於轉錄扮演是抑制的角色,但是這時 若是有adenoviruse E1A這個蛋白質出現時 ,則是扮演促進轉錄的角色,接 著下來Hariharan等人也發現YY-1具有促進一些核糖體蛋白質基因(rpL30, rpL32)進行轉錄的功能,同時Park以及Atch ison等人發現YY-1具有調節免 疫球蛋白基因上加強區之功能,因而他們也叫YY-1為NF-E1,最後,Flanagan 等人,則稱YY-1是UCRBP,因為他們發現它具有抑制老鼠白血球病毒的LTR進 行轉錄的功能。在本論文中,我經由比較UCR(upstream conserved region)結合序列 CGCCATTTT與SCD2啟動子PRE結合序列AGCCATTTC。發現 一個共同因子可以結合到這二者的結合序列上,從競爭性的原性電泳膠遲 緩試驗中,我已經証實UCR和SCD2的序列專一性的確很相似。更進一步研究 顯示UCR和SCD2上的結合因子具有相同抗原性,於是,我們可以下一個結論: 普遍存在之核內因子,YY-1,可以認知SCD2啟動子上的PRE。至於,YY-1在 SCD2上扮演何種角色,尚需進一步實驗才得以知曉。
49
Lin, Yun-Shan, et 林妘珊. « Carnosic acid suppresses 3T3-L1 preadipocyte differentiation through down-regulation of PPARγ by activation of SIRT1/FoxO1 pathway ». Thesis, 2013. http://ndltd.ncl.edu.tw/handle/46920465279930275928.
Texte intégralRésumé :
碩士中國醫藥大學
營養學系碩士班
101
Carnosic acid (CA), a rosemary diterpene, possesses anti-oxidant, anti-inflammatory, neuroprotection, lipid-lowering and anti-obesity properties. The aim of this study was to investigate the anti-adipogenic effect of CA in 3T3-L1 preadipocytes and the mechanism involved in its action. The results indicated that CA at 5-20 μM did not reduce cell viability. CA decreased lipid accumulationand inhibited the protein and mRNA levels of CCAAT/enhancer-binding protein (C/EBP) α and β and peroxisome proliferator-activated receptor (PPAR)γ, leading to a decrease of fatty acid synthase (FAS) expression in 3T3-L1 adipocytes. The phosphorylation of AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase (ACC) were increased by CA in a dose-dependent manner. CA decreased the phosphorylation of Akt and stimulated the protein expression of SIRT1 and FoxO1.CA also decreased the acetylation and phosphorylation of Foxo1. Treatment cells with sirtinol (SIRT1 inhibitor), CA decreased the protein expression of SIRT1 and FoxO1. In addition, the inhibition of lipid accumulation and PPARγ SEAP activity by CA was reversed in the cells treated with sirtinol or Compound C (an AMPK inhibitor) (p<0.05).In conclusion, CA inhibited 3T3-L1 preadipocyte differentiation through modulation of the AMPK and SIRT1/Foxo1 pathways. Therefore, CA may be a promising antiobesity agent.
50
Chang, Yi-Fang, et 張以芳. « A polyacetylene of Bidens pilosa inhibit adipogenesis via calreticulin was regulated by GATA-3 in 3T3-L1 preadipocyte ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/16646563948391543603.
Texte intégralRésumé :
碩士國立中興大學
獸醫學系暨研究所
100
There is a lot of metabolism disease could cause obesity, like type 2 diabetes and cardiovascular disease. It is always existing conflict between safety and efficacy in developing anti obesity drugs. Extract herbal compounds which inhibited adipogenesis with safty are gradually become the priority choice of anti obesity drugs developing. Calreticulin (CRT) is a major Ca2+ - buffering protein in the lumen of endoplasmic reticulum, which control intracellular calcium homeostasis and activate the calcineurin (CaN), a downstream factor of CRT, to inhibit the differentiation of adipocyte. We use cytopiloyne (CP), a polyacetylene of Bidens pilosa, to confirm the anti adipogenesis effect through regulate CRT expression in adipocyte. First, we culture the 3T3-L1 preadipocyte in the medium, which is containing induced differentiation factor, 3-isobuty-1-methulanthine (IBMX), dexamethasone (DEX) and insulin. We find that CP can inhibit the differentiation of adipocyte and get lower adipogenic marker expression, such as PPARγ, C/EBPα, aP2, adiponectin. Then, use western blotting and electrophysiology to prove that CP can increase CRT expression and intracellular calcium concentration. FK506, a CaN inhibitor, reversed the anti-adipogenesis effect on CP incubated 3T3-L1 preadipocyte. These results confirmed that CP inhibited adipogenesis through CRT pathway. Finally, a GATA-3 siRNA experiments indicated that CP enhance CRT expression was GATA-3 dependent. This study shows that CP is a novel phytocompound, which offered a new anti-adipogenesis mechanism.