Teses / dissertações sobre o tema "Neurotrophic peptide"
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Littrell, Ofelia Meagan. "NIGROSTRIATAL DOPAMINE-NEURON FUNCTION FROM NEUROTROPHIC-LIKE PEPTIDE TREATMENT AND NEUROTROPHIC FACTOR DEPLETION". UKnowledge, 2011. http://uknowledge.uky.edu/neurobio_etds/1.
Texto completo da fonteKaska, Jennifer Lynn. "Ependymin Mechanism of Action: Full Length EPN VS Peptide CMX-8933". Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0528103-102730/.
Texto completo da fonteParikh, Suchi Vipin. "Ependymin peptide mimetics that assuage ischemic damage increase gene expression of the anti-oxidative enzyme SOD". Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0429103-132144.
Texto completo da fonteWu, Yu. "Neuroprotective liquid crystalline cubosome and hexosome nanoparticle formulations by self-assembly of plasmalogen lipids and a neurotrophic peptide". Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASQ003.
Texto completo da fonteThe primary aim of this thesis is to investigate the neuroprotective effect of plasmalogens (Pls) and explore the potential of lipid nanoparticles against neurodegenerative diseases. Our strategy aims to create a self-assembled system, enhancing the efficacy of plasmalogens and the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) for neuroprotection. The Pls, a distinctive group of membrane glycerophospholipids, typically contain a polyunsaturated fatty acyl chain at the sn-2 position and an alkyl chain linked by a vinyl-ether bond at the sn-1 position of the glycerol backbone. Pls, with their unique structure featuring a vinyl ether bond, possess free radical scavenging capabilities and antioxidant properties. Addressing the decline in plasmalogen levels in aging individuals holds promise for therapies related to Parkinson's disease, Alzheimer's disease, and dementia. Recent research has expanded our understanding of their antioxidant effects, anti-inflammation, and their involvement in ferroptosis. However, challenges persist in implementing plasmalogens in treatments of neurodegenerative diseases and in developing suitable drug delivery systems. We summarize the progress in lipid nanoparticles (LNPs) for targeting multiple neurodegeneration mechanisms. Our research on plasmalogen-loaded LNPs explores their fabrication mechanism and in vitro/in vivo impacts on neurodegenerative models. Our study shows the feasibility of enhancing Pls efficacy using LNPs as carriers. We employ natural plasmalogens from scallops to create nanoformulations involving a non-lamellar lipid excipient (MO) for structural stabilization, various surfactants, and small amounts of vitamin E, curcumin, or coenzyme Q10. Using small-angle X-ray scattering (SAXS), we identified the structural features of various LNPs (vesicles, cubosomes, and hexosomes). Our in vitro evaluations utilized human neuroblastoma SH-SY5Y cells, differentiated with 10 µM retinoic acid for 5 days. Cell viability tests indicated non-toxicity of the LNPs at a total lipid concentration of 10 µM for 24-hour incubation. We study the impact of Pls nanoparticles on an in vitro model of Parkinson's disease using neuronal cells induced by the neurotoxin 6-OHDA. Using the SH-SY5Y cell line, we explore cellular damage mechanisms (oxidative stress and apoptotic enzymes) via identifying the impact on the ERK-Akt-CREB-BDNF signaling pathway. Several documented neuroprotective compounds were used to demonstrate the ability to restore neuronal lesions caused by 6-OHDA, offering a model of neurodegenerative conditions to further elucidate the beneficial effects of the Pls-based LNPs. We then focus on the cAMP response element binding protein (CREB) and its phosphorylation leading to neurotrophin expression, crucial in preventing neurological disorders. Through lipid peptide nano-assemblies, we studied the impact of different structural organizations of the LNPs on CREB phosphorylation in an in vitro model of Parkinson's disease. Notably, liquid crystalline lipid nanoparticles loaded with plasmalogens prolonged CREB activation under neurodegenerative conditions, showing potential for enhanced neuroregeneration through sustained CREB activation in response to the neurotrophic nanoassemblies. In a mouse model of Parkinson's disease, vesicle and hexosome LNPs demonstrated distinct effectiveness in restoring motor function. The nanomedicine-mediated intervention influenced Parkinson's disease-related gene regulation and rebalanced lipid profiles. Nasal administration of Pls-loaded LNPs improved disease behavioral symptoms and downregulated genes like IL33 and Tnfa. The obtained results indicated the significant impact of hexosomal LNP nanomedicines on disease attenuation, lipid metabolism, and responsive gene modifications potentially involved in regeneration
Grimsholm, Ola. "Neuropeptides and neurotrophins in arthritis : studies on the human and mouse knee joint". Doctoral thesis, Umeå universitet, Integrativ medicinsk biologi, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1863.
Texto completo da fonteLim, Robyn Renata. "Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase activating polypeptide (PACAP) : peptide neurotrophic actions in comparison with those of nerve growth factor (NGF) on rat adrenal pheochromocytoma PC12 cells". Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627532.
Texto completo da fonteZussy, Charleine. "Caractérisation des effets de l'injection intracérébroventriculaire du peptide β-amyloïde [25-35] chez le rat mâle adulte : impact sur un système de neuroprotection endogène : le BDNF (Brain-derived neurotrophic factor) et ses récepteurs". Montpellier 2, 2009. http://www.theses.fr/2009MON20204.
Texto completo da fonteAlzheimer's disease is a neurodegenerative pathology characterized by the presence of senile plaques. The major component of senile plaques is an amyloid-ß protein (Aβ). In this study, we assessed the time-course effects and regional changes observed after a single intracerebroventricular (icv) injection of aggregated Aβ fragment [25-35] (Aβ25-35; 10 µg/rat), on physiological parameters (body weight, general activity and body temperature), behavioral responses (spatial short- and long-term memories), stress parameters (BDNF and CORT levels, oxidative, inflammation, neuroprotection, cellular) and on histological parameters (neuroinflammation, acetylcholine systems, hippocampus integrity, BDNF system). We shown that a single icv injection of Aβ25-35 has a significant impact on short- and long-term memories, HPA axis activity, oxidative stress, brain level of a neuroprotective agent (BDNF) and its receptors (TrkB and p75), ER and mitochondrial stress, apoptotic processes, astrogliosis and microgliosis, cholinergic systems, hippocampus integrity and hippocampal neurogenesis. This study allows to realize the parallel existing between the effects induced by Aβ25-35 icv injection and numerous relevant signs of the pathology observed in patients. It seems that effects observed could be due to differential regulation of BDNF system on cerebral regions
Farias, Caroline Brunetto de. "BDNF/TrkB em câncer colorretal : interações funcionais com GRPR e EGFR". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/72306.
Texto completo da fonteBDNF / TrkB are described in various cancers where they participate in tumor growth, apoptosis, angiogenesis and metastasis. Furthermore, other growth factors are also important to tumorigenesis as GRP/GRPR and EGF/EGFR. Therefore, the aim of this study was to investigate the role of BDNF/TrkB in colorectal cancer evaluating the interactions with GRPR and EGFR. We found that BDNF and its receptor, TrkB, are present in samples from patients diagnosed with sporadic colorectal cancer, and BDNF levels were higher in tumor tissue compared to adjacent tumor tissue. Treatment with RC-3095, GRPR antagonist, in human colorectal cancer cell line, HT-29 caused a decrease in NGF levels secreted by cells, and generated increase of BDNF when compared to untreated control. RC-3095 inhibited the proliferation and cell viability in HT-29 (EGFR positive) and SW-620 (EGFR negative), but only HT-29 cells showed a significant increase in BDNF mRNA expression. Therefore, a monoclonal anti-EGFR antibody, cetuximab was combined with RC-3095 in HT-29 cells, and was able to prevent such an increase, suggesting that this effect is mediated by EGFR. The treatment with a Trk inhibitor, K252a (1000 nM) or cetuximab (10 nM), inhibited cell proliferation. However, the combination of BDNF with cetuximab prevented this effect, whereas the combination of ineffective doses of K252a (10 nM) with cetuximab (1 nM) still inhibited cell proliferation of HT-29. Furthermore, cetuximab also caused an increase in BDNF and TrkB mRNA expression, 600 minutes after treatment. In summary, our results suggest that inhibition of cell proliferation in vitro or tumor growth in vivo must occur between the combination of GRPR and TrkB in EGFR positive colorectal cancer cells, and that BDNF is also involved in drug resistance mechanisms. Therefore, blockage of BDNF / TrkB may emerge as potential antitumor target.
Dyer, Jason Kim. "Presence of melanocortin receptors in Schwann cells in culture & functional relevance to the neurotrophic response : with an appendix on the establishment & characterisation of a new rat Schwann cell line". Thesis, University of Bristol, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238825.
Texto completo da fonteKritz, Angelika. "Peptides from phage display libraries for targeted gene delivery via the p75 neurotrophic receptor". Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408712.
Texto completo da fonteBasille, Magali. "Contribution à l'étude des récepteurs du pituitary adenylate cyclase-activating polypeptide (PACAP) au cours de l'ontogénèse du cervelet de rat. Recherche d'une activité trophique potentielle du PACAP sur les neuroblastes cérébelleux". Rouen, 1998. http://www.theses.fr/1998ROUES010.
Texto completo da fonteArca, Turkan. "Attempts to clone the Limulus ependymin gene, and the effects of a human ependymin peptide on human SHSY neuroblastoma cells". Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-050405-180333/.
Texto completo da fonteRezende, Alexandre Cesar Santos de. "Investigação da ação neuroprotetora do fator neurotrofico ciliar (CNTF) conjugado com peptideo contendo dominio de translocação de proteina (PTD)". [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317520.
Texto completo da fonteTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-14T01:41:43Z (GMT). No. of bitstreams: 1 Rezende_AlexandreCesarSantosde_D.pdf: 5210413 bytes, checksum: 60e511530e7c408001bf455f9968219f (MD5) Previous issue date: 2009
Resumo: O fator neurotrófico ciliar (CNTF) despertou grande interesse com a descoberta do seu efeito neuroprotetor sobre motoneurônios após secção de nervos periféricos em ratos neonatos e camundongos adultos. Contudo, seus efeitos colaterais de perda de peso e caquexia impedem seu uso clínico. Uma via alternativa muito promissora, no sentido de eliminar estes efeitos colaterais, parece ser a administração do CNTF conjugado com peptídeos que possuem domínio de translocação de proteínas (PTD-protein transduction domain). Previamente, mostramos que o CNTF conjugado a um PTD derivado da proteína tat do vírus HIV-1 (TAT-CNTF) também tem efeito protetor sobre motoneurônios e não produziu efeitos colaterais no tratamento, por 5 dias, de ratos neonatos (P2-P7) que sofreram secção do nervo isquiático. O presente trabalho teve como objetivo investigar se a administração da TAT-CNTF por tempos mais prolongados seria capaz de manter a sobrevivência de motoneurônios e neurônios sensoriais, bem como de estimular a regeneração axonal, sem a ocorrência dos efeitos colaterais do CNTF. Desta forma, ratos Wistar neonatos (P2) receberam tratamento subcutâneo com CNTF (1,2mg/g/dia) durante 5 dias, TATCNTF (1,2mg/g/dia) ou PBS durante 5 ou 15 dias. Ao final do período de tratamento os animais foram sacrificados por decapitação, sendo coletado para posterior análise o sangue e gorduras marrom interescapular, branca retroperitonial e branca epididimal. Um outro grupo de animais tive o nervo isquiático esquerdo esmagado em P2 e recebeu o mesmo tratamento. No período entre 20 e 60 dias de vida foi realizada a avaliação da recuperação funcional motora por meio de Walking Track Test, e da recuperação funcional sensitiva através da medida do limiar da resposta de retirada da pata a um estímulo elétrico. No 30º ou 60º dia de vida foi realizada marcação retrógrada de neurônios cujos axônios compõem o nervo isquiático utilizando-se Amina Dextrano Biotinilado (BDA). Após 7 dias, os animais foram sacrificados, sendo coletada a intumescência lombar, os gânglios sensoriais L4 e L5 e o nervo isquiático para análise histológica. As análises dos níveis plasmáticos de glicose, triglicérides e ácidos graxos revelaram que o tratamento com TAT-CNTF ou CNTF por igual período (5 dias) produziu modificações no metabolismo energético em relação aos ratos controle (PBS), contudo diferiram quanto à intensidade dos efeitos produzidos. O tratamento prolongado com TAT-CNTF (15 dias) produziu significantes alterações nas concentrações plasmáticas de triglicérides e de colesterol. Entretanto, o tratamento com TAT-CNTF (5 ou 15 dias) produziu efeitos reduzidos sobre os tecidos adiposos quando comparados ao tratamento com CNTF. Os ratos do grupo TAT-CNTF apresentaram peso corporal significativamente menor que aqueles do grupo PBS a partir do 9º dia de tratamento, porém o grupo CNTF apresentou menor peso a partir do 2º dia. Em ambos tratamentos houve reversão desse efeito sobre o peso corporal, porém esta ocorreu mais precocemente nos ratos do grupo TAT-CNTF (P25) quando comparados ao grupo CNTF (P32). A recuperação funcional motora e sensorial dos grupos CNTF e TAT-CNTF foi 50% superior ao grupo controle. Os grupos CNTF e TAT-CNTF também apresentaram maior número de neurônios sensoriais e motores BDA positivos, além de maior número de axônios mielínicos no nervo isquiático quando comparados ao grupo controle. Nossos resultados mostraram que o tratamento com TAT-CNTF, mesmo por períodos mais longos, promoveu a sobrevivência e regeneração axonal de motoneurônios e neurônios sensitivos sem a ocorrência dos efeitos colaterais produzidos pelo tratamento com CNTF. Além disso, tais propriedades da TAT-CNTF contribuíram significativamente para a recuperação funcional motora e sensorial após lesões nervosas periféricas.
Abstract: Ciliary neurotrophic factor (CNTF) is known as a neuroprotective agent on motoneurons after peripheral nerve section in neonatal rats and adult mice. However, side effects like weight loss and caquexia have limited its clinical use. A promising approach for the avoidance of such side effects is the fusion of a protein transduction domain (PTD) with CNTF. Previously we showed that CNTF fused with HIV-1 PTD (TAT-CNTF) also had protective effect on motoneurons and did not produce side effects in a 5 days treatment of sciatic nerve transected neonatal rats (P2-P7). The aim of the present work was investigate if the TAT-CNTF administration for long time was capable to support the motoneurons and sensory neurons survival, as well as to stimulate the axonal regeneration, without CNTF side effects. Thus, neonatal Wistar rats (P2) were subcutaneously treated with CNTF (1.2mg/g/day) for 5 days, TAT-CNTF (1.2mg/g/day) or PBS during 5 or 15 days. By the end of treatment rats were killed by decaptation and blood, intrascapular brown adipose tissue and retroperitonial and epididimal white adipose tissue were collected for further analysis. Another group of animals had the left sciatic nerve crushed (NCE) in P2 and received the same treatment. From 20 to 60 days of age a Walking Track Test was performed in order to evaluate the motor function recovery, and the threshold for paw withdraw was used as a measure of sensitive functional recovery. The retrograde labeling of sciatic nerve neurons using Biotinilated Dextran Amine (BDA) was performed at 30 or 60 days of age. Rats were killed after 7 days and the lumbar enlargement, L4 and L5 dorsal root ganglia and the sciatic nerve were collected for histological analysis. The analysis glucose, triglycerides and fatty acid plasmatic levels demonstrated that 5 days TAT-CNTF or CNTF treatment induced changes in energy metabolism compared to control rats, however the effects of these treatments had different intensities. The long term treatment with TAT-CNTF (15 days) induced important changes in triglycerides and cholesterol plasmatic levels. However TAT-CNTF treatment (5 or 15 days) had reduced effects on adipose tissue when compared to CNTF. After the 9th day of treatment the TAT-CNTF group had a smaller body weight when compared to the PBS group, on the other hand the CNTF group had a smaller body weight after the 2nd day compared to the PBS group. In both treatments (CNTF and TATCNTF) there was a reversion of the body weight effect, however this was earlier in the TAT-CNTF group (P25) than on the CNTF group (P32). The motor and sensorial functional recovery of CNTF and TAT-CNTF groups was 50% greater than the control group. CNTF and TAT-CNTF groups also displayed a greater number of BDA positive motor and sensory neurons, and more myelinic axons in the sciatic nerve compared to the control group. Our results demonstrate that TAT-CNTF long term treatment was able to promote the survival and axonal regeneration of motor and sensory neurons without important CNTF related side effects. Moreover, TAT-CNTF properties had significant contribution for the motor and sensory functional recovery after peripheral nerve lesion.
Doutorado
Biologia Celular
Doutor em Biologia Celular e Estrutural
Petit-Dop, Florence. "Effets de deux neurotrophines, BDNF et NT3, et d'un nouveau peptide, le "Melanin concentrating hormone Gene Overprinted Polypeptide" (MGOP) sur le développement de neurones hypophysiotropes de Rat in vitro". Paris 11, 2001. http://www.theses.fr/2001PA11T031.
Texto completo da fonteJerónimo-Santos, André. "Brain-derived neurotrophic factor and adenosine signalling on amyloid-β peptide induced toxicity : impact on hippocampal function". Doctoral thesis, 2014. http://hdl.handle.net/10451/15639.
Texto completo da fonteBrain-derived neurotrophic factor (BDNF) and its high-affinity full-length receptor, TrkB-FL, play a central role in the nervous system by providing trophic support to neurons and by regulating synaptic transmission and plasticity. BDNF signalling is impaired in Alzheimer’s disease (AD), a neurodegenerative disorder characterized, among other features, by the accumulation of the amyloid-β (Aβ) peptide. Although the mechanisms implicated in the reduction of BDNF signalling in AD were not clarified, the reestablishment of BDNF actions is considered as a promising strategy for AD treatment. In last decade it became clear that most of synaptic actions of BDNF, including the ones upon synaptic transmission, plasticity or upon neurotransmitter release, are fully dependent on adenosine A2A receptors (A2AR) activation. However, evidences indicate that A2AR antagonists can prevent the deficits in AD animal models. Given the lack of data clarifying the mechanisms behind the changes on BDNF signalling, namely changes on TrkB receptors, and the knowledge that A2AR activation facilitates most of BDNF synaptic actions, the main goal of this project was to study the impact of Aβ peptides and A2AR on BDNF signalling. This work revealed that in rat primary neuronal cultures Aβ selectively increases mRNA levels for the truncated TrkB-T1 and TrkB-T2 isoforms without affecting TrkB fulllength (TrkB-FL) mRNA levels. Moreover, Aβ increases protein levels of total pool of truncated TrkB receptors (TrkB-Tc) and decreases TrkB-FL protein levels. This effect is explained by the Aβ-induced calpain-mediated cleavage on TrkB-FL receptors, downstream of Shc binding site, which results in the formation of a new truncated TrkB receptor (TrkB-T’) and a new intracellular fragment (TrkB-ICD), which is also detected in post-mortem human brain samples. In hippocampal slices it was observed that Aβ impairs BDNF function in a calpaindependent way, upon modulation of GABA and glutamate release from hippocampal nerve terminals, and upon modulation of long-term potentiation (LTP). Finally, the exogenous BDNF strongly reduces the Aβ-induced activation of caspase-3 and calpain in neuronal cultures, an effect not affected by A2AR agonist or antagonist. Moreover, for the first time it was shown that chronic in vivo blockade of A2AR by a selective antagonist, prevents the facilitatory action of BDNF upon ex-vivo CA1 hippocampal LTP and decreases both mRNA and protein levels of the TrkB-FL receptor in rat hippocampus. In conclusion, the present work shows that Aβ induces a TrkB-FL cleavage mediated by calpain and impairs BDNF-mediated effects in synaptic plasticity and neurotransmitter release in a calpain-dependent way. While the BDNF action upon synaptic plasticity is abolished under chronic in vivo A2AR blocking conditions, the protective actions of this neurotrophin against Aβ toxicity were found to be dependent on A2AR activation.
O factor neurotrófico derivado do cérebro (Brain-derived neurotrophic factor- BDNF) e o seu receptor de alta afinidade, TrkB-FL, desempenham um papel central no sistema nervoso, dado que promovem suporte trófico aos neurónios e que regulam a transmissão e plasticidade sinápticas. A sinalização mediada pelo BDNF encontra-se diminuída na doença de Alzheimer (Alzheimer’s disease -AD), uma doença neurodegenerativa na qual ocorre acumulação do péptido beta amilóide (amyloid-beta -Aβ). Apesar dos mecanismos envolvidos na redução da sinalização mediada pelo BDNF na AD não serem totalmente conhecidos, o restabelecimento das acções do BDNF tem sido considerado como uma estratégia promissora para a terapêutica desta doença. Na última década tornou-se claro que a maioria das acções sinápticas do BDNF, incluindo as acções na transmissão e plasticidade sinápticas e também na libertação de neurotransmissores, é dependente da activação dos receptores A2A da adenosina (A2AR). Contudo, o uso de antagonistas dos A2AR tem sido apontado como uma possível estratégia terapêutica para o tratamento da AD. Dada a falta de evidências que clarifiquem os mecanismos envolvidos nas alterações da sinalização mediada pelo BDNF e o conhecimento de que a activação dos A2AR facilita a maioria das acções sinápticas do BDNF, o objectivo principal desta tese foi estudar o impacto dos péptidos Aβ e dos A2AR na sinalização mediada pelo BDNF. Este trabalho revelou que, em culturas primárias de neurónios corticais, o Aβ aumenta os níveis de mRNA dos receptores TrkB truncados, TrkB-T1 e TrkB-T2, sem afectar os níveis de mRNA dos receptores TrkB completos, TrkB-FL. Por outro lado, verificou-se que o Aβ aumenta os níveis proteicos do conjunto de receptores TrkB truncados e que diminui os níveis proteicos dos receptores TrkB-FL, por um mecanismo independente da proliferação glial e da activação de caspases. Foi ainda possível concluir que o Aβ induz a clivagem, mediada por calpaínas, dos receptores TrkB-FL, esta clivagem dá-se após o local de ligação da Shc e antes do início do domínio de cinase de tirosina, pelo que origina um novo receptor TrkB truncado (TrkB-T’), contendo o local de ligação à Shc, e um novo fragmento intracelular (TrkBintracellular domain- ICD), contendo a totalidade do domínio da cinase. No entanto, a presença destes fragmentos, não mostrou afectar a fosforilação do receptor TrkB-FL induzida pela exposição ao BDNF. Interessantemente, foi possível detectar o fragmento TrkB-ICD em uma amostra, post-mortem, de cérebro humano. Mostrou-se também que a inibição das calpaínas previne as alterações dos níveis proteicos das isoformas do TrkB, induzidas pelo Aβ, sem afectar as alterações ao nível do mRNA do TrkB. Por outro lado, este trabalho revelou que o BDNF exógeno reduz a activação da caspase-3 e das calpaínas induzida pelo Aβ, de uma forma independentemente dos A2AR. Em fatias de hipocampo de ratos adultos, este trabalho mostrou que o Aβ diminui as acções do BDNF na plasticidade sináptica, nomeadamente na potenciação de longa duração (Long-term potentiation, LTP) na área CA1 do hipocampo, bem como no seu efeito sobre libertação de neurotransmissores (GABA e glutamato) de sinaptosomas. Notavelmente, o inibidor das calpaínas, MDL28170, mostrou restabelecer os efeitos do BDNF, na presença do péptido Aβ, tanto na plasticidade sináptica como na libertação de neurotransmissores. Este trabalho permitiu ainda concluir que o bloqueio crónico dos A2AR, in-vivo, através da administração de um antagonista selectivo (KW-6002), previne o efeito potenciador do BDNF na LTP, registada ex-vivo na área CA1 do hipocampo, e que diminui os níveis de mRNA e de proteína do receptor TrkB-FL, no hipocampo de rato. Em suma, o presente trabalho revelou que o péptido Aβ induz a clivagem dos receptores TrkB-FL, mediada pelas calpaínas, e que bloqueia as acções mediadas pelo BDNF na plasticidade sináptica e na libertação de GABA e glutamato por um mecanismo dependente da actividade das calpaínas. Se por um lado, o efeito do BDNF na plasticidade sináptica é perdido aquando da inibição crónica dos A2AR, o efeito protector desta neurotrofina contra a toxicidade induzida pelo Aβ mostrou-se independente da activação dos A2AR.
Fundação para a Ciência e a Tecnologia (FCT)
Ng, Tiffany. "The Effect of Teneurin C-terminal Associated Peptide-1 (TCAP-1): Protection Against Hypoxic-stress and Regulation of Brain-derived Neurotrophic Factor (BDNF) in Immortalized Hypothalamic N38 Cells". Thesis, 2010. http://hdl.handle.net/1807/25875.
Texto completo da fonteNnanabu, Ernest. "C10 semi-peptoid beta-turn peptidomimetics: syntheses, characterization and biological studies". 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1710.
Texto completo da fonte