31 research outputs found

    Saturated Fatty Acids Modulate Autophagy's Proteins In The Hypothalamus

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Autophagy is an important process that regulates cellular homeostasis by degrading dysfunctional proteins, organelles and lipids. In this study, the hypothesis that obesity could lead to impairment in hypothalamic autophagy in mice was evaluated by examining the hypothalamic distribution and content of autophagic proteins in animal with obesity induced by 8 or 16 weeks high fat diet to induce obesity and in response to intracerebroventricular injections of palmitic acid. The results showed that chronic exposure to a high fat diet leads to an increased expression of inflammatory markers and downregulation of autophagic proteins. In obese mice, autophagic induction leads to the downregulation of proteins, such as JNK and Bax, which are involved in the stress pathways. In neuron cell-line, palmitate has a direct effect on autophagy even without inflammatory activity. Understanding the cellular and molecular bases of overnutrition is essential for identifying new diagnostic and therapeutic targets for obesity.103Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [2011/14565-4, RA 2011/51205-6

    Defective Apoptosis In Intestinal And Mesenteric Adipose Tissue Of Crohn's Disease Patients.

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    Crohn's disease (CD) is associated with complex pathogenic pathways involving defects in apoptosis mechanisms. Recently, mesenteric adipose tissue (MAT) has been associated with CD ethiopathology, since adipose thickening is detected close to the affected intestinal area. However, the potential role of altered apoptosis in MAT of CD has not been addressed. To evaluate apoptosis in the intestinal mucosa and MAT of patients with CD. Samples of intestinal mucosa and MAT from patients with ileocecal CD and from non-inflammatory bowel diseases patients (controls) were studied. Apoptosis was assessed by TUNEL assay and correlated with the adipocytes histological morphometric analysis. The transcriptional and protein analysis of selected genes and proteins related to apoptosis were determined. TUNEL assay showed fewer apoptotic cells in CD, when compared to the control groups, both in the intestinal mucosa and in MAT. In addition, the number of apoptotic cells (TUNEL) correlated significantly with the area and perimeter of the adipose cells in MAT. Transcriptomic and proteomic analysis reveal a significantly lower transcript and protein levels of Bax in the intestinal mucosa of CD, compared to the controls; low protein levels of Bax were found localized in the lamina propria and not in the epithelium of this tissue. Furthermore, higher level of Bcl-2 and low level of Caspase 3 were seen in the MAT of CD patients. The defective apoptosis in MAT may explain the singular morphological characteristics of this tissue in CD, which may be implicated in the pathophysiology of the disease.9e9854

    Toll-like Receptor 4, F4/80 And Pro-inflammatory Cytokines In Intestinal And Mesenteric Fat Tissue Of Crohn's Disease.

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    Crohn's disease (CD) is a chronic intestinal ailment with a multifactorial etiology, whose incidence has increased during the last three decades. Recently, a role for mesenteric fat has been proposed in CD pathophysiology, since fat hypertrophy is detected nearby the affected intestinal area; however, there are few studies on this aspect. To evaluate inflammatory activity in intestinal mucosa and mesenteric fat tissue of patients with CD and controls. Ten patients with ileocecal CD and 16 patients with non-inflammatory disease (control groups) were studied. The specimens were snap-frozen and the expression of TLR-4, F4/80, IL1-β and IL-6 were determined by immunoblot of protein extracts. TLR4 RNA level were measured using RT-PCR. The t Test was applied (p<0.05). The local ethical committee approved the study. The intestinal mucosa of CD group had significantly higher protein levels of TLR-4, F4/80, IL-1β and IL-6 than the controls. The gene expression of TLR4 was lower in the intestinal mucosa of CD compared to the control group. Regard the mesenteric fat tissue, there was no statistical difference related to TLR-4, F4/80, IL-1β and IL-6 proteins expression. These findings may result from an up-regulation of macrophage activation and intracellular pathways activated by bacterial antigens, which are more important in intestinal mucosa than fat tissue in CD patients. This may represent an anomalous regulation of innate immunity and could contribute to the production of proinflammatory mediators and disease development.698-10

    Smarcad1 mediates microbiota-induced inflammation in mouse and coordinates gene expression in the intestinal epithelium

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    Background How intestinal epithelial cells interact with the microbiota and how this is regulated at the gene expression level are critical questions. Smarcad1 is a conserved chromatin remodeling factor with a poorly understood tissue function. As this factor is highly expressed in the stem and proliferative zones of the intestinal epithelium, we explore its role in this tissue. Results Specific deletion of Smarcad1 in the mouse intestinal epithelium leads to colitis resistance and substantial changes in gene expression, including a striking increase of expression of several genes linked to innate immunity. Absence of Smarcad1 leads to changes in chromatin accessibility and significant changes in histone H3K9me3 over many sites, including genes that are differentially regulated upon Smarcad1 deletion. We identify candidate members of the gut microbiome that elicit a Smarcad1-dependent colitis response, including members of the poorly understood TM7 phylum. Conclusions Our study sheds light onto the role of the chromatin remodeling machinery in intestinal epithelial cells in the colitis response and shows how a highly conserved chromatin remodeling factor has a distinct role in anti-microbial defense. This work highlights the importance of the intestinal epithelium in the colitis response and the potential of microbial species as pharmacological and probiotic targets in the context of inflammatory diseases

    Modulation of hypothalamic autophagy in hypothalamus of mice fed with high-fat diet

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    Orientador: Marciane Milanski FerreiraDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências AplicadasResumo: O hipotálamo mediobasal é conhecido como o local primário que coordena o balanço entre a ingestão alimentar e o gasto energético. Nesse contexto, dietas com alto conteúdo de ácidos graxos saturados são apontadas como fatores dietéticos importantes responsáveis pelo desenvolvimento da obesidade. Dados recentes demonstraram que a autofagia, um processo que regula a homeostase celular por degradar organelas e proteínas disfuncionais, é crucial para a manutenção da funcionalidade de neurônios hipotalâmicos AgRP e POMC, que por sua vez, são responsáveis por coordenar o balanço energético corporal. Nesse trabalho, avaliamos a distribuição e o conteúdo de proteínas da maquinaria da autofagia em um modelo animal de obesidade induzida por dieta hiperlipídica com 8 ou 16 semanas de dieta e também em resposta a injeções intracerebroventriculares de ácido graxo esteárico. Demonstramos que a exposição crônica à dieta hiperlipídica levou ao aumento da expressão de marcadores inflamatórios e diminuição de autofagia. Além disso, o tratamento intracerebroventricular com ácido esteárico parece ser capaz de diminuir a autofagia em hipotálamo, sugerindo que ácidos graxos saturados podem ser os responsáveis pela diminuição da autofagia encontrada nos animais obesos. Por fim, a indução de autofagia em animais obesos com rapamicina foi capaz de melhorar a homeostase da glicose e reverter parâmetros inflamatórios e metabólicos, sem alterar o peso e a ingestão alimentar dos animais. Entender os mecanismos celulares e moleculares destes processos é crucial para identificar novos alvos terapêuticos para a obesidadeAbstract: The mediobasal hypothalamus is known as the primary site which coordinates the balance between food ingestion and energy expenditure. In this context, diets with high content of saturated fatty acids are pointed as the main diet factor responsible for the development of obesity. Recent data have shown that autophagy, a process which regulates cellular homeostasis by degrading dysfunctional proteins and organelles, is crucial to maintain the functionality of hypothalamic AgRP and POMC neurons, which in turn are responsible for coordinate body energy homeostasis. In this study we evaluated the hypothalamic distribution and content of autophagy's machinery proteins in an animal model of diet-induced obesity at 8 or 16 weeks of high-fat diet and in response to intracerebroventricular injections of a saturated fatty acid. We demonstrate that chronic exposure to a high-fat diet can lead to an increased expression of inflammatory markers and downregulation of autophagy. Also, intracerebroventricular treatment with stearic acid appears to contribute to the decrease of hypothalamic autophagy, suggesting that saturated fatty acids can contribute to the downregulation of autophagy found in obese mice. Finally, induction of autophagy in obese mice with rapamycin was able to improved glucose homeostasis and reverse inflammatory and apoptosis markers, the main mechanisms involving dysregulation of energy balance related to hypothalamic neurons, while no weight loss was observed during the treatmentMestradoMetabolismo e Biologia MolecularMestra em Ciências da Nutrição e do Esporte e Metabolism

    Regulation of hypothalamic chaperone-mediated autophagy in response to lipid overload

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    Orientadores: Marciane Milanski Ferreira, Adriana Souza TorsoniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências AplicadasResumo: A obesidade é um problema de saúde global e está diretamente associada com o risco de desenvolvimento de outras doenças metabólicas. Um estilo de vida saudável, incluindo uma alimentação equilibrada, é essencial para a manutenção da eutrofia. Os mamíferos possuem um poderoso sistema que é responsável pela regulação da homeostasia energética, sendo que, no hipotálamo estão localizados neurônios relacionados com o acoplamento entre a fome e a saciedade. Estes neurônios são afetados pela ingestão excessiva de lipídeos, especialmente por ácidos graxos saturados de cadeia longa, e pela obesidade. Sabe-se que a obesidade é marcada pela presença de uma inflamação subclínica e alteração em diversas vias relacionadas ao estresse celular. Em camundongos com obesidade induzida por dieta hiperlipídica, há falha na regulação da macroautofagia e do sistema ubiquitina-proteasoma em neurônios do hipotálamo, que são mecanismos responsáveis pela proteostasia celular. Este trabalho teve como objetivo investigar a modulação de autofagia mediada por chaperonas em neurônios hipotalâmicos de animais obesos. Esse tipo de autofagia é responsável por degradar proteínas citosólicas que contém um motivo específico de aminoácidos, por meio da atuação principal de duas proteínas, denominadas de HSC-70 e LAMP-2A. Nossos resultados mostraram que animais que consumiram dieta hiperlipídica por 3 dias apresentaram maior ativação de autofagia mediada por chaperonas em hipotálamo. Após este período, houve menor ativação de autofagia mediada por chaperonas nesta região. Além disso, neurônios hipotalâmicos expostos ao palmitato, um ácido graxo saturado, apresentaram ativação de autofagia mediada por chaperonas. A exposição destes neurônios hipotalâmicos a um ambiente inflamatório também levou à ativação de autofagia mediada por chaperonas nessas células. Em situações de estresse celular, a ativação da autofagia mediada por chaperonas é essencial para a manutenção da proteostasia. Em contrapartida, a diminuição neste sistema leva a maior suceptibilidade celular a estímulos estressores. Portanto, o excesso de ácidos graxos saturados afeta a autofagia mediada por chaperonas em neurônios do hipotálamo, fato que pode contribuir para a disfunção neuronal e formação de agregados proteicos. A manutenção dos níveis basais de autofagia por meio de intervenções farmacológicas ou dietéticas pode representar uma terapia importante no tratamento de doenças metabólicasAbstract: Obesity has become a global health issue and is directly related to increased risk of developing other metabolic diseases. A healthy lifestyle, including a balanced diet, is essential for the maintenance of a healthy body mass. Mammals have a powerful system responsible for the regulation of energy homeostasis. Neurons from hypothalamus are responsible for the coupling between food intake and satiety. These neurons are affected by lipid excess, especially long-chain saturated fatty acids and obesity. A subclinical inflammatory state is the hallmark of obesity. Also, obesity leads to the dysregulation of several systems related to stress response. In mice with diet-induced obesity, there is a failure in the regulation of macroautophagy and ubiquitin-proteasome system in hypothalamic neurons. These systems are responsible for the cytosolic protein renewal and therefore for cellular proteostasis. This work aimed to study the chaperone-mediated autophagy modulation in obese mice. This type of autophagy is responsible for the degradation of proteins which have a specific amino acid motif. There are two main proteins responsible for chaperone-mediated autophagy machinery, called HSC-70 and LAMP-A. Our results showed an upregulation in chaperone-mediated autophagy in the hypothalamus of mice fed a high-fat diet for 3 days. Longer exposure to high-fat diet led to the downregulation in hypothalamic chaperone-mediated autophagy. Furthermore, direct exposure of hypothalamic neurons to palmitate, a saturated fatty acid, led to chaperone-mediated autophagy activation. After an insult, the activation of chaperone-mediated autophagy is essential for proteostasis maintenance. On the other hand, failure in this system could lead to increased cellular susceptibility to stressors. Thus, saturated fatty acid excess affects neuronal chaperone-mediated autophagy and this could contribute to neuronal dysfunction and protein aggregate formation in hypothalamic neurons. Therefore, the maintenance of basal chaperone-mediated autophagy levels with pharmacology or dietary interventions could represent an important therapy in the treatment of metabolic disordersDoutoradoMetabolismo e Biologia MolecularDoutora em Ciências da Nutrição e do Esporte e Metabolismo2013/10911-0FAPES

    A substituição da fife pelo flautim como instrumento de iniciação à flauta transversal

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    O presente Relatório de Estágio é constituído pela descrição do trabalho ao longo do ano letivo 2018/2019 na Academia de Música de Costa Cabral, no âmbito da Prática de Ensino Supervisionada de Instrumento - flauta transversal. Além disto, a minha experiência enquanto docente tem-me levantado dúvidas e desafios aos quais procuro continuamente dar resposta, sendo que, um dos mais frequentes é a adaptação inicial ao instrumento, pela sua natureza pouco ergonómica. Por essa razão, o conteúdo de investigação deste relatório é inspirado nessa problemática e tem como objetivo reunir informação e possíveis soluções a ser aplicadas no futuro. O relatório está dividido em três capítulos. No primeiro é apresentada a Academia de Música de Costa Cabral, assim como caracterizada a sua instituição, a equipa de docentes e não docentes existente, a sua oferta educativa e, especificamente, a disciplina de Flauta Transversal. O segundo capítulo é dedicado à Prática de Ensino Supervisionada, onde além de ser apresentado e contextualizado o meu percurso na academia, se inclui a caracterização do perfil escolar e psicológico dos alunos com quem trabalhei, um exemplo de registo de observação e de lecionação e, para concluir, a devido balanço geral do trabalho realizado ao longo do ano. Por fim, o terceiro capítulo, de natureza teórica, traduz-se num projeto de investigação. Com a realização do mesmo, pretendo propor o flautim como alternativa de instrumento introdutório à flauta transversal já que, como é devidamente fundamentado no capítulo III, as soluções que se põem em prática atualmente não anulam na totalidade os problemas que podem diminuir a qualidade do ensino e aprendizagem da flauta na infância. A metodologia utilizada recai, essencialmente, sobre a reflexão de um trabalho de observação e dos resultados de um inquérito destinado a outros professores, comparando-os e fundamentando-os com a revisão da literatura previamente elaborada.This Internship Report consists of a description of the work done during the 2018/2019 academic year at Academia de Música de Costa Cabral, within the scope of the Supervised Teaching Practice - flute. In addition, my experience as a flute teacher has raised doubts and challenges that I continually seek to answer. One of the most frequent problem is the initial adaptation to the instrument, due to its little ergonomic nature. For this reason, the research content of this report is inspired by this issue and aims to gather information and possible solutions to be applied in the future. The report is divided into three chapters. In the first, Academia de Música de Costa Cabral is presented, as well as its institution, the teaching and non-teaching team, its educational offer and, specifically, the discipline of Flute. The second chapter is dedicated to the the Supervised Teaching Practice, where besides presenting and contextualizing my path in that school, it includes the characterization of the academic and psychological profile of the students I worked with, an example of observation and teaching record and, to conclude, a proper balance of the work done during the year. Finally, the third chapter, theoretical in nature, is made of a research project. By doing so, I intend to propose the piccolo as an alternative introductory instrument to the flute since, as is well founded in this chapter, the solutions currently being implemented do not completely nullify the problems that may diminish the quality of learning the flute in childhood. The methodology used is essentially the reflection of an observation work and the results of a inquiry aimed at other teachers, comparing them and basing them with the review of literature previously done

    Ileal pouch of ulcerative colitis patients exhibit impaired autophagy

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    sem informação1131S28FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temAnnual meeting on advances in inflammatory bowel diseases: multidisciplinary approaches to IBD patient-centered car

    Autophagy and proinflammatory cytokine expression in the intestinal mucosa and mesenteric fat tissue of patients with Crohn's disease

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    BACKGROUND: Recently, mesenteric fat has been proposed to play a role in the pathophysiology of Crohn's disease (CD), as fat hypertrophy is detected close to the affected intestinal area; however, there are few studies regarding autophagy and creeping fat tissue in CD. OBJECTIVE: Evaluate autophagy-related proteins and proinflammatory cytokines in intestinal mucosa and mesenteric fat in patients with CD and controls. PATIENTS AND METHODS: Ten patients with CD, eight with non-inflammatory disease who underwent surgery, and eight with normal ileocolonoscopy were studied. The expression of LC3-II, TNF-&#945; and IL-23 was determined by immunoblot of protein extracts. In addition, total RNA of LC3 and Atg16-L1 were determined using RT-PCR. RESULTS: The expression of LC3-II was significantly lower in the mesenteric tissue of CD when compared to controls (p < 0.05). In contrast, the intestinal mucosa of the CD group had higher levels of LC3-II (p < 0.05). However, mRNA expression of autophagy-related proteins was similar when compared to mesenteric fat groups. TNF-&#945; and IL-23 expressions were higher in intestinal mucosa of CD than in control (p < 0.05). CONCLUSION: These findings suggest a defect in the autophagic activity of the creeping fat tissue in CD, which could be involved with the maintenance of the inflammatory process in the intestinal mucosa
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