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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Characterization of Centrally Expressed Solute Carriers : Histological and Functional Studies with Transgenic Mice / : His

Roshanbin, Sahar January 2016 (has links)
The Solute Carrier (SLC) superfamily is the largest group of membrane-bound transporters, currently with 456 transporters in 52 families. Much remains unknown about the tissue distribution and function of many of these transporters. The aim of this thesis was to characterize select SLCs with emphasis on tissue distribution, cellular localization, and function.       In paper I, we studied the leucine transporter B0AT2 (Slc6a15). Localization of B0AT2 and Slc6a15 in mouse brain was determined using in situ hybridization (ISH) and immunohistochemistry (IHC), localizing it to neurons, epithelial cells, and astrocytes. Furthermore, we observed a lower reduction of food intake in Slc6a15 knockout mice (KO) upon intraperitoneal injections with leucine, suggesting B0AT2 is involved in mediating the anorexigenic effects of leucine.     In paper II, we studied the postnatal, forebrain-specific deletion of Slcz1, belonging to the SLC18 family, in conditional KO mice (cKO). We observed a decreased response to diazepam and a higher neuronal activity in cortex and hippocampus of cKO mice, as well as an impairment in short-term recognition memory. Intracellular expression was found in neurons but not astrocytes with IHC, indicating SLCZ1 is implicated in neuronal regulation of locomotion and memory.    In paper III, we performed the first detailed histological analysis of PAT4, a transporter belonging to the SLC36 family, involved in the activation of mTOR complex 1 on lysosomes. We found abundant Slc36a4 mRNA and PAT4 expression in mouse brain, using ISH and IHC. We used IHC to localize PAT4 to both inhibitory and excitatory neurons and epithelial cells. We also found both intracellular- and plasmalemmal expression and partial colocalization of PAT4 with lysosomal markers.    Lastly, in paper IV, we provided the first tissue mapping of orphan transporter MCT14 (SLC16A14). Using qPCR, we detected moderate to high Slc16a14 mRNA in the central nervous system and kidney. We found widespread Slc16a14 and MCT14 in mouse brain using ISH and IHC. We also found MCT14 to have intracellular and plasmalemmal expression in mainly excitatory but also inhibitory neurons, as well as epithelial cells. We found MCT14 to be most closely related to MCT8, MCT2 and MCT9, suggesting a similar role for this transporter.
12

mTORC1 Activates SREBP-2 through Maintenance of Endosomal Cycling and Suppression of Autophagy

Eid, Walaa January 2017 (has links)
The mammalian target of rapamycin complex 1 (mTORC1) is known to regulate lipogenesis through sterol regulatory element binding proteins (SREBPs), master regulators of cholesterol and fatty acid synthesis. Through an incompletely understood mechanism, mTORC1 triggers translocation of SREBPs, an endoplasmic reticulum (ER) resident protein, to the Golgi, where mature SREBP is proteolytically produced to activate transcription of lipogenic genes. Low ER cholesterol is a well-known trigger for SREBPs activation, which includes translocation, maturation, and transcriptional activation. The study investigated whether mTORC1 activates SREBP by limiting cholesterol delivery to the ER. The findings indicate an increase in mTORC1 activity is accompanied by lower ER cholesterol and by SREBP-2 activation, a transcription factor primarily responsible for cholesterol synthesis. A decrease in mTORC1 activity, on another hand, coincides with higher ER cholesterol and lower SERBP-2 activity. I further report that this ER cholesterol is of lysosomal origin, as blocking the exit of cholesterol from lysosomes by U18666A or NPC1 siRNA prevents ER cholesterol from rising and, consequently, SREBP-2 is activated without mTORC1 activation. I identified two membrane trafficking processes, triggered by low mTORC1 activity, supply the lysosomes with cholesterol: autophagy and re-routing of endosomes to lysosomes. Indeed, a dual blockade by Atg5-/- and rab5 kept the ER cholesterol low even when mTORC1 activity was low, and resulted in SREBP-2 activation. Conversely, over-expressing Atg7, which forces autophagy, raises the ER cholesterol and suppresses SREBP-2 activity even when mTORC1 activity is high. Thus, it can be concluded that mTORC1 actively suppresses the formation of autophagosomes and promotes endosomal recycling, both of which prevents cholesterol to reach the lysosomes, thereby reducing cholesterol levels in the ER and activating SREBP-2.
13

Metabolic regulation of insulin secretion: the link between excess glucose, mechanistic target of rapamycin complex 1 & hyperinsulinemia

Rumala, Courtney 07 October 2019 (has links)
Obesity, a major risk factor in the development of Type 2 Diabetes (T2D), is commonly associated with insulin resistance and hyperinsulinemia. The long accepted view has been that insulin resistance drives hyperinsulinemia; however, there are multiple lines of evidence that hyperinsulinemia can precede and drive insulin resistance. The signals and mechanisms by which chronic excess nutrients promote pancreatic β-cell dysfunction remain poorly understood. This prompted us to define the signaling events that contribute to basal insulin hypersecretion induced by excess glucose. Of particular interest is signaling through mechanistic target of rapamycin complex 1 (mTORC1), a nutrient sensitive kinase complex whose hyperactivation has been shown to promote hyperinsulinemia. Clonal ß-cells (INS-1 cells) with and without mTORC1 inhibition were pre-exposed to physiological (5mM) or excess (11mM) glucose for 4 to 24 hrs. Basal insulin secretion, respiration and metabolites were measured. Pre-exposure to excess glucose resulted in sustained mTORC1 hyperactivation, basal insulin secretion, higher basal respiration and increased maximal respiratory capacity, due to accelerated mitochondrial pyruvate metabolism. Inhibition of mTORC1 reduced basal insulin secretion, basal respiration and maximal respiratory capacity. Moreover, cells challenged with excess glucose had increased levels of glycolysis and TCA cycle intermediates. Our results suggest that hyperactivation of mTORC1 induced by excess glucose results in increased energy demand and in the generation of metabolic factors that can lead to basal insulin hypersecretion. Therefore, targeting mitochondrial pyruvate metabolism and /or mTORC1 signaling could potentially lead to specific therapies to control hyperinsulinemia and diabetes progression.
14

The Essential Role of the Non-Essential Amino Acid Asparagine in Lymphoid Malignancies

Srivastava, Sankalp 05 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Cancer cells display increased metabolic demands to support their proliferation and biosynthetic needs. It has been extensively shown in cancers, that amino acids have functions beyond the role of mRNA translation. The breadth of functions makes amino acid restriction an effective strategy for cancer therapy; hence an important line of research involves targeting amino acid acquisition and metabolism therapeutically. Currently, asparagine depletion via L-Asparaginase in acute lymphoblastic leukemia (ALL) remains the only clinically approved therapy to date. In the first project, we showed that ALL cells are auxotrophic for asparagine and rely on exogenous sources for this non-essential amino acid. However, sensitivity to L-Asparaginase therapy is mitigated by the expression of the enzyme asparagine synthetase (ASNS), involved in de novo asparagine biosynthesis. We showed that this adaptive response requires two essential steps; demethylation of the ASNS promoter and recruitment of activating transcription factor 4 (ATF4) to the promoter to drive ASNS transcription. Our follow-up study in ALL cells showed that asparagine bioavailability (through de novo biosynthesis or exogenous sources) is essential to maintain the expression of the critical oncogene c-MYC. c-MYC is a potent transcription factor and is dysregulated in over 60% of cancers, including hematopoietic malignancies. We showed that this regulation by asparagine is primarily at the translation level and c-MYC expression is rescued only when exogenous asparagine is available or when cells can undertake de novo biosynthesis. At the biochemical level, asparagine depletion also causes an induction of ATF4 mediated stress response and suppression of global translation mediated by decreased mammalian target of rapamycin complex 1 (mTORC1) activity. However, we found that neither inhibition of the stress response or rescuing global translation rescued c-MYC protein expression. We also extended this observation to c-MYC-driven lymphomas using cell lines and orthotopic in vivo models. We showed that genetic inhibition of ASNS or pharmacological inhibition of asparagine production can significantly limit c-MYC protein and tumor growth when environmental asparagine is limiting. Overall, our work shows an essential role for asparagine in lymphoid cancers and has expanded on the usage of L-Asparaginase to resistant leukemias and lymphomas.
15

The roles of mTOR essential adaptor proteins, raptor and rictor, in temporal lobe epileptogenesis

Godale, Christin 23 August 2022 (has links)
No description available.
16

Intramuscular Anabolic Signaling and Endocrine Response Following Different Resistance Exercise Protocols In Trained Men

Gonzalez, Adam 01 January 2015 (has links)
The mammalian/mechanistic target of rapamycin complex 1 (mTORC1) signaling pathway appears to be the primary regulator of protein synthesis and growth. While resistance exercise paradigms are often divided into hypertrophy (HYP) and strength (STR) protocols, it is unknown whether these protocols differentially stimulate mTORC1 signaling. The purpose of this study was to examine mTORC1 signaling in conjunction with circulating hormone concentrations following a typical lower-body HYP and STR resistance exercise protocol. Ten resistance-trained men (24.7±3.4y; 90.1±11.3kg; 176.0±4.9cm) performed each resistance exercise protocol in a random, counterbalanced order. Blood samples were obtained at baseline (BL), immediately (IP), 30 minutes (30P), 1 hour (1H), 2 hours (2H), and 5 hours (5H) post-exercise. Fine needle muscle biopsies were completed at BL, 1H, and 5H. Electromyography of the vastus lateralis was also recorded during each protocol. HYP and STR produced a similar magnitude of muscle activation across sets. Myoglobin and lactate dehydrogenase concentrations were significantly greater following STR compared to HYP (p=0.01-0.02), whereas the lactate response was significantly higher following HYP compared to STR (p=0.003). The GH, cortisol, and insulin responses were significantly greater following HYP compared to STR (p=0.0001-0.04). No significant differences between protocols were observed for the IGF-1 or testosterone response. Intramuscular anabolic signaling analysis revealed a significantly greater (p=0.03) phosphorylation of IGF-1 receptor at 1H following HYP compared to STR. Phosphorylation status of all other signaling proteins including mTOR (mammalian target of rapamycin), p70S6k (ribosomal S6 kinase 1), and RPS6 (ribosomal protein S6) were not significantly different between trials. Despite significant differences in markers of muscle damage and the endocrine response following STR and HYP, both protocols appeared to elicit similar mTORC1 activation in resistance-trained men.
17

Expressão dos genes da via mTORC1 e seu envolvimento nas Neoplasias Mieloproliferativas / A. mTORC1 gene expression and involvement in Myeloproliferative Neoplasms

Nunes, Natália de Souza 09 March 2016 (has links)
As Neoplasias Mieloproliferativas (NMPs) se caracterizam por apresentarem acúmulo de eritrócitos, leucócitos e plaquetas morfologicamente normais e seus precursores. Nos últimos anos vários estudos buscaram conhecer os mecanismos celulares e moleculares envolvidos na fisiopatologia e evolução dessas desordens, com o intuito de encontrar marcadores de diagnóstico, prognóstico e terapias eficazes. A mutação pontual no gene que codifica a enzima Janus Kinase 2 (JAK2 V617F), presente em aproximadamente 90% dos pacientes com PV e em 50% dos pacientes com TE e MF, foi o principal achado genético anormal associado a essas doenças. Essa mutação resulta na ativação constitutiva da enzima JAK2 e na desregulação da proliferação celular e resistência à apoptose. Nosso grupo de pesquisa descreveu em PV, TE e MF a expressão alterada de genes reguladores da apoptose e dados da literatura indicam que a desregulação do ciclo celular contribui para a fisiopatologia das NMPs. Nesse projeto o intuito foi investigar a associação da via de sinalização m-TOR com as alterações do ciclo celular e via JAK/STAT nas NMPs. A via de sinalização m-TOR participa dos processos celulares de sobrevivência e proliferação. A estratégia experimental foi avaliar a expressão de genes e proteínas, reguladores da via m-TOR, em leucócitos de pacientes com NPMC e linhagens celulares JAK2+ tratadas com inibidores de JAK2 e AKT. Para determinar a relação da via m-TOR nas NMPs foi escolhido o gene eIF4E, alterado nessas doenças, para observar sua modulação diante da inibição farmacológica nas linhagens celulares JAK2 positivas. Os resultados desse estudo contribuem para a descrição de novos alvos terapêuticos dependentes e indepentendes da atividade quinase JAK2 e para o melhor conhecimento da participação da via de sinalização m-TOR na fisiopatologia das NMPs. / The myeloproliferative neoplasms (MNPs) are characterized by accumulation of erythrocytes, leukocytes and platelets morphologically normal and their precursors. In recent years several studies have sought to understand the cellular and molecular mechanisms involved in the pathophysiology and progression of these disorders in order to find diagnostic and prognostic markers and effective therapies. The point mutation in the gene encoding the enzyme Janus kinase 2 (JAK2 V617F), present in approximately 90% of PV patients and in 50% of patients with ET and MF was the main abnormal genetic finding associated with these diseases. This mutation results in constitutive activation of JAK2 enzyme and the deregulation of cell proliferation and resistance to apoptosis. Our research group described in PV, ET and MF altered expression of apoptosis regulatory genes and literature data suggest that deregulation of the cell cycle contributes to the pathophysiology of MNPs. In this project the aim was to investigate the signaling pathway of the association m-TOR with the changes of the cell cycle and JAK / STAT in NMPs. The signaling pathway participates in the m-TOR cell survival and proliferation processes. The experimental strategy was to evaluate the expression of genes and proteins, regulators of m-TOR pathway in leukocytes from patients with and NPMC cell lines treated with the JAK2 JAK2 + and AKT inhibitors. To determine the relationship of m-TOR pathway with MNPs has been selected the eIF4E gene deregulated in these disorders to observe their modulation in pharmacologically inhibited cells lines JAK 2 positive. Results of this study contribute to the description of new therapeutic targets of dependent and independent JAK2 kinase activity and to a better understanding of the signaling pathway of participation m-TOR in the pathophysiology of NMPs.
18

Mécanisme d’activation neuronale de mTORC1 et de son altération par le peptide amyloïde β / Mechanism of neuronal activation of mTORC1 and its alteration by amyloid β peptide

Khamsing, Dany 29 November 2017 (has links)
MTOR est une sérine/thréonine kinase appartenant au complexe mTORC1 (mTOR Complexe 1), un régulateur clé de la traduction. Ce complexe joue un rôle au sein de la LTP (Potentialisation à Long Terme), une forme de plasticité synaptique qui requiert la synthèse de nouvelles protéines pour renforcer la transmission synaptique. La première partie de ma thèse porte sur les mécanismes de régulation de la voie mTORC1 dans les neurones. Dans les cellules non neuronales, cette voie de signalisation est classiquement régulée par deux voies distinctes. D’une part, les acides aminés induisent le recrutement du complexe mTORC1 à la membrane des endo-lysosomes où la protéine Rheb est enrichie et favorisent ainsi l’activation de mTORC1. D’autre part, les facteurs de croissance activent mTORC1 en stimulant la voie PI3K/Akt/TSC/Rheb. Nos résultats indiquent que les neurones sont capables d’ "utiliser" le mécanisme responsable de la translocation de mTORC1 en réponse à la supplémentation en acides aminés pour coupler l’induction de la plasticité synaptique à l’activation de mTORC1. En effet, les récepteurs NMDA et le BDNF, deux acteurs centraux de la LTP, augmentent le recrutement de mTORC1 à la membrane des endo-lysosomes même en absence d’acides aminés, et activent mTORC1. Par des stratégies induisant la translocation de mTORC1 à la membrane des endo-lysosomes, nous avons montré que ce mécanisme est important pour l’activation de mTORC1 mais n’est pas suffisant : il faut également une activation de la protéine Rheb. Le second aspect de mon projet porte sur la régulation de mTORC1 dans le cadre de la maladie d’Alzheimer, une maladie neurodégénérative caractérisée par une perte progressive de la mémoire. Les déficits cognitifs s’accompagnent d’un dysfonctionnement progressif des synapses suivi par la perte neuronale, tous deux causés par une accumulation anormale du peptide amyloïde β (Aβ). Les données de la littérature montrent que les oligomères toxiques du peptide Aβ (AβO) inhibent la plasticité synaptique dans les stades précoces de la maladie. Cependant, les mécanismes restent obscurs. Plusieurs études mettent en évidence une altération de la voie mTORC1. Nos résultats montrent que les AβO inhibent le recrutement de mTORC1 à la membrane des endo-lysosomes. Ce mécanisme est rétabli par une inhibition pharmacologique de l’AMPK. Ainsi, ces données indiquent que les AβO inhibent l’adressage de mTORC1 aux compartiments endo-lysosomaux via l’AMPK. Cela aurait pour conséquence une inhibition de la synthèse protéique décrite dans la littérature et contribuerait ainsi au dysfonctionnement synaptique. / MTOR is a serine/threonine kinase that belongs to mTORC1 (mTOR complex 1), a key regulator of translation. This complex is involved in LTP (Long Term Potentiation), a form of synaptic plasticity requiring new protein synthesis to reinforce synaptic transmission. The first part of my thesis investigates the mechanism of mTORC1’s regulation in neurons. In non-neuronal cells, mTORC1 pathway is commonly activated by two distinct pathways. On the one hand, amino acids induce mTORC1 recruitment to the membrane of endo-lysosomes where Rheb is enriched and can thus promote mTORC1 activation. On the other hand, growth factors activate mTORC1 via the PI3K/Akt/TSC/Rheb pathway. Our results indicate that neurons are capable of “using” amino acid-induced translocation of mTORC1 to connect synaptic plasticity induction to mTORC1 activation. Indeed, NMDA receptors and BDNF, two main actors of synaptic plasticity, increase mTORC1 recruitment to the membrane of endo-lysosomes even in the absence of amino acids, and activate mTORC1. Using strategies targeting mTORC1 to endo-lysosomes, we show that this mechanism promotes activation of mTORC1 but is not sufficient: Rheb activation is also required. The second part of my project is focused on the regulation of mTORC1 in Alzheimer’s disease, a neurodegenerative pathology characterized by a progressive memory loss. Cognitive deficits are widely believed to result from a progressive dysfunction of synapses, followed by a loss of neurons, both caused by an abnormal accumulation of the amyloid β peptide (Aβ). Data from others show that toxic Aβ oligomers (AβOs) inhibit synaptic plasticity at early stages of the disease. However, the mechanisms remain poorly understood. Several studies indicate an alteration of the mTORC1 pathway. Our results show that AβOs inhibit mTORC1 recruitment to the membrane of endo-lysosomes and that this effect can be rescued by a pharmacological inhibition of AMPK. Thus our data indicate that AβOs inhibit mTORC1 translocation to endo-lysosomal compartments via AMPK. This could lead to the impairment of protein synthesis reported in other studies and thus alter synaptic function.
19

Expressão dos genes da via mTORC1 e seu envolvimento nas Neoplasias Mieloproliferativas / A. mTORC1 gene expression and involvement in Myeloproliferative Neoplasms

Natália de Souza Nunes 09 March 2016 (has links)
As Neoplasias Mieloproliferativas (NMPs) se caracterizam por apresentarem acúmulo de eritrócitos, leucócitos e plaquetas morfologicamente normais e seus precursores. Nos últimos anos vários estudos buscaram conhecer os mecanismos celulares e moleculares envolvidos na fisiopatologia e evolução dessas desordens, com o intuito de encontrar marcadores de diagnóstico, prognóstico e terapias eficazes. A mutação pontual no gene que codifica a enzima Janus Kinase 2 (JAK2 V617F), presente em aproximadamente 90% dos pacientes com PV e em 50% dos pacientes com TE e MF, foi o principal achado genético anormal associado a essas doenças. Essa mutação resulta na ativação constitutiva da enzima JAK2 e na desregulação da proliferação celular e resistência à apoptose. Nosso grupo de pesquisa descreveu em PV, TE e MF a expressão alterada de genes reguladores da apoptose e dados da literatura indicam que a desregulação do ciclo celular contribui para a fisiopatologia das NMPs. Nesse projeto o intuito foi investigar a associação da via de sinalização m-TOR com as alterações do ciclo celular e via JAK/STAT nas NMPs. A via de sinalização m-TOR participa dos processos celulares de sobrevivência e proliferação. A estratégia experimental foi avaliar a expressão de genes e proteínas, reguladores da via m-TOR, em leucócitos de pacientes com NPMC e linhagens celulares JAK2+ tratadas com inibidores de JAK2 e AKT. Para determinar a relação da via m-TOR nas NMPs foi escolhido o gene eIF4E, alterado nessas doenças, para observar sua modulação diante da inibição farmacológica nas linhagens celulares JAK2 positivas. Os resultados desse estudo contribuem para a descrição de novos alvos terapêuticos dependentes e indepentendes da atividade quinase JAK2 e para o melhor conhecimento da participação da via de sinalização m-TOR na fisiopatologia das NMPs. / The myeloproliferative neoplasms (MNPs) are characterized by accumulation of erythrocytes, leukocytes and platelets morphologically normal and their precursors. In recent years several studies have sought to understand the cellular and molecular mechanisms involved in the pathophysiology and progression of these disorders in order to find diagnostic and prognostic markers and effective therapies. The point mutation in the gene encoding the enzyme Janus kinase 2 (JAK2 V617F), present in approximately 90% of PV patients and in 50% of patients with ET and MF was the main abnormal genetic finding associated with these diseases. This mutation results in constitutive activation of JAK2 enzyme and the deregulation of cell proliferation and resistance to apoptosis. Our research group described in PV, ET and MF altered expression of apoptosis regulatory genes and literature data suggest that deregulation of the cell cycle contributes to the pathophysiology of MNPs. In this project the aim was to investigate the signaling pathway of the association m-TOR with the changes of the cell cycle and JAK / STAT in NMPs. The signaling pathway participates in the m-TOR cell survival and proliferation processes. The experimental strategy was to evaluate the expression of genes and proteins, regulators of m-TOR pathway in leukocytes from patients with and NPMC cell lines treated with the JAK2 JAK2 + and AKT inhibitors. To determine the relationship of m-TOR pathway with MNPs has been selected the eIF4E gene deregulated in these disorders to observe their modulation in pharmacologically inhibited cells lines JAK 2 positive. Results of this study contribute to the description of new therapeutic targets of dependent and independent JAK2 kinase activity and to a better understanding of the signaling pathway of participation m-TOR in the pathophysiology of NMPs.
20

Estudo funcional e morfológico renal da prole de ratos cujas mães foram submetidas à restrição proteica gestacional : efeito do tratamento com rapamicina / The functional and morphological renal study and the rapamycin treatment effects in the male offspring rats : whose mothers underwent gestational protein restriction

Canale, Vinicius, 1986- 25 August 2018 (has links)
Orientadores: José Antônio Rocha Gontijo, Flávia Fernandes Mesquita / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T07:43:12Z (GMT). No. of bitstreams: 1 Canale_Vinicius_M.pdf: 2382904 bytes, checksum: bf0d6a9b4243b86411026cd098372cc8 (MD5) Previous issue date: 2014 / Resumo: Já está bem documentado que a dieta hipoproteica em ratos durante a gestação produz efeitos no crescimento fetal, uma persistente elevação na pressão arterial e disfunções no desenvolvimento renal da prole. Alterações na pressão arterial parecem estar relacionadas à acentuada redução no número de nefros que acaba por causar um quadro de hipertrofia e hiperfluxo nos nefros remanescentes como adaptação para equilibrar a taxa de filtração, no entanto, os mecanismos utilizados para esta adaptação culminam com o surgimento de albuminúria. Este processo acaba por causar esclerose glomerular culminando em um ciclo, comprometendo cada vez mais os nefros remanescentes. O desenvolvimento deste quadro pode levar à síndrome nefrótica e posteriormente à doença renal terminal. Acredita-se que o principal fator atuante na programação fetal neste modelo é devido à exposição exacerbada do feto aos glicocorticoides materno, o que acaba por comprometer a correto desenvolvimento e diferenciação de tecidos e órgãos, e na expressão ou atividade de uma série de receptores e enzimas. Recentemente, tem surgido a hipótese de que a atividade da mTORC poderia estar envolvida no surgimento de doenças na idade adulta neste modelo experimental. Este trabalho teve por objetivo avaliar se a inibição da mTORC através do tratamento com rapamicina em animais programados poderia ser benéfico, inibindo o surgimento de complicações relacionadas com a estrutura glomerular e como seria seu efeitos sistêmico, sobre a função renal e pressão arterial sistêmica. Ratos Wistar receberam ração com baixa proteína (6% LP) e dieta controle (17% NP) durante o período gestacional. A prole de machos foi tratada com rapamicina diluída em DMSO (5%) e administrada via intraperitoneal na dose de 1mg/kg, 3 vezes por semana, a partir da 4ª semana de vida até a 12ª semana. A aferição da pressão arterial sistólica foi realizada nas idades 8, 12 e 16. Foi observado que nos grupos que receberam rapamicina, a pressão artéria sistólica elevou-se consideravelmente em todas as idades. A avaliação da função renal foi realizada através de clearance de creatinina e lítio nas mesmas idades e observamos que durante todo o tratamento, o grupo NP que recebeu rapamicina excretou mais sódio, na porção pós-proximal do túbulo. Além disso, não houve diferença na taxa da filtração glomerular em nenhuma das idades. Quando a proteinúria foi avaliada, observamos que o grupo programado LP sem rapamicina, apresentou evolução com o passar das semanas sendo significativamente maior a partir das 12ª e 16ª semanas, no entanto, os grupos que receberam rapamicina, não apresentaram a mesma evolução, indicando preservação da estrutura glomerular. Os presentes resultados demonstram que apesar de a rapamicina ter elevado a pressão arterial em ambos os grupos, há uma indicação de que os animais programados tem um controle menos eficaz no controle da pressão arterial através da função renal. Mesmo diante da pressão elevada, a rapamicina foi capaz de inibir injúrias à barreira de filtração / Abstract: It is well established that a low protein diet in rats during pregnancy causes effects on fetal growth, a persistent elevation in blood pressure and renal dysfunction in the offspring at a later age. Alterations in blood pressure seem to be related to the marked reduction in the number of nephrons which ultimately causes an overflow and hypertrophy in the remaining nephrons in the attempt to adapt its balance on the filtration rate. However, the mechanisms used for this adaptation results in the appearance of albuminuria. This process might cause glomerular sclerosis culminating in a cycle, increasing the damage to the remaining nephrons. The development of this framework can lead to nephrotic syndrome and subsequently to ESRD. It is believed that the main factor in the fetal programming model is the fetus overexposure to maternal glucocorticoids, which ultimately compromises the proper development and differentiation of tissues and organs. Additionally, the expression and the activity of a number of receptors and enzymes is also affected. Recently, in this experimental model, there has arisen the hypothesis that the activity of mTORC could be involved in the onset of disease in adulthood. This study assess whether the inhibition of mTORC, through the treatment with rapamycin in programmed animals, could be beneficial by inhibiting the onset complications related to glomerular structure and its affect on renal function and blood pressure. Wistar female rats were fed with low protein (6 % LP) or control diet (17 % NP) during pregnancy. The male offspring were treated with rapamycin diluted in DMSO (5 %) and administered intraperitoneally at a dose of 1mg/kg, 3 times per week, from the 4th week of life until the 12th week. The measurement of systolic blood pressure was measured at 8, 12, and 16 weeks old. We noticed that in the groups treated with rapamycin the arterial systolic pressure rose considerably in all ages. The assessment of renal function was performed by creatinine clearance and lithium at the same ages as the blood pressures assessment. The NPR group that received rapamycin had an increase in sodium excretion at the post- proximal tubule during the whole treatment. Additionally, there was no difference in the rate of glomerular filtration rate at any age among the groups. When proteinuria was assessed, we found that the programmed Group LP without rapamycin, showed an increase along the weeks and as expected, the groups that have received rapamycin did not show the same trend, indicating preservation in the glomerular structure. The present results demonstrate that rapamycin caused increase in the blood pressure in both groups however, it was able still to inhibit the injury into the filtration barrier. Additionally, there is an indication that the programmed animals, has a less effective control in the blood pressure and the excretion of sodium, even when the treatment is interrupted / Mestrado / Fisiopatologia Médica / Mestre em Ciências

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