A Utilização de Vídeos no Ensino: Uma Experiência Prática com Alunos de Graduação

O ensino de fisiologia endócrina faz parte do currículo dos estudantes da área de Ciências Biomédicas. Contudo, em função da necessidade de um conjunto de conhecimentos bem fundamentados de Biologia Celular, Molecular e Bioquímica, há dificuldade na assimilação desse tópico, principalmente por alunos dos primeiros dois anos de graduação, o que cria a necessidade do uso de diferentes estratégias de ensino-aprendizagem para a apropriação desses conhecimentos. Quando empregado de forma coerente com a proposta pedagógica, o vídeo em sala de aula pode ser uma ferramenta útil para a superação dessa dificuldade. Com esse intuito nos propusemos a utilizar essa estratégia junto aos alunos do primeiro semestre de graduação da Escola de Educação Física e Esporte da Universidade de São Paulo, como uma atividade em grupo em sala de aula, a fim de motivá-los a desenvolver uma leitura crítica da mídia em relação ao conteúdo de Fisiologia Endócrina, mais especificamente de fisiologia das glândulas adrenais e do metabolismo do cálcio e do fósforo. Com a introdução dos vídeos em sala de aula, tornaram-se notórios o maior interesse e o envolvimento dos alunos na realização das atividades propostas, possibilitando: (a) melhor aproveitamento do conteúdo previamente trabalhado em sala de aula, o que certamente facilitou o aprendizado; e (b) o estabelecimento de correlações entre fatos do cotidiano e a liberação e ação de hormônios naquele contexto determinado.The endocrine physiology teaching is part of the curriculum of the students of the Biomedical Sciences area. However, the need of a set of well-founded knowledge of Cell and Molecular Biology, as well as Biochemistry subjects, turns this topic very difficult to be understandable, mainly for the students of the first semesters. This creates the need of using different teaching and learning strategies for the appropriation of these knowledges. When applied in a coherent way in conjunction with the pedagogical proposal, the use of videos in the classrooms could be a useful tool to help to overcome this difficulty. In this context, we have used this strategy as a group activity in the classroom, with undergraduate students of the first semester of the Faculty of Physical Education and Sport of the Universidade de São Paulo. We aimed to lead them to develop a critical evaluation of the media in relation to Endocrine Physiology content, specifically the physiology of the adrenal glands and the calcium and phosphorus metabolism. With the introduction of videos in the classroom, it became notorious the great interest and involvement of the students in carrying out the proposed activities. This allowed: (a) a better comprehension of the content previously taught in the classroom, which certainly facilitated the learning process and (b) the ability to make correlations between routine events and the release of hormones and their action in that specific context

Effects of zinc supplementation on the development of insulin resistance induced by high fat diet in mice.

O aumento da prevalência do diabete melito do tipo 2 (DM2) é intenso e implica ampla busca pela prevenção e tratamento da doença. Estudos têm mostrado a participação do zinco na síntese, secreção e via de sinalização da insulina e sobre o controle glicêmico. Este trabalho objetivou analisar o mecanismo de ação do zinco no controle da secreção de insulina e no controle glicêmico, de modo a entender se a suplementação com o zinco previne ou retarda a manifestação do DM2. O projeto foi aprovado pela CEUA-ICB (USP). Camundongos machos C57BL/6 foram divididos em 4 grupos experimentais: dieta controle (NFD); dieta controle suplementada com ZnCl2 (NFDZ); dieta hiperlipídica (HFD); e dieta hiperlipídica suplementada com ZnCl2 (HFDZ). A massa corporal, a ingestão de ração e água e a glicemia foram acompanhados semanalmente. Testes intraperitoneais de tolerância à glicose (ipGTT) e à insulina (ipITT) foram realizados na 14ª semana de tratamento. Completado as 15 semanas de tratamento a glicemia, a insulinemia e a zincemia foram analisadas, sendo aplicados os testes de HOMA-IR e HOMA-&#946;. Em ilhotas pancreáticas isoladas foi analisada a secreção estática de insulina em diferentes concentrações de glicose. O teste de captação e metabolismo de glicose foi feito no músculo sóleo e a análise do conteúdo das proteínas AKT e GSK3-&#946; foi feita no músculo sóleo e no fígado. Os dados (média±SEM) foram analisados por Two-way ANOVA com pós-teste Bonferoni ou por teste t de Student (P 0,05). A suplementação com zinco melhorou a disfunção glicêmica induzida por dieta hiperlipídica, sem no entanto afetar a resistência à insulina ou a secreção de insulina por ilhotas isoladas.The increase in prevalence of type 2 diabetes mellitus (DM2) is intense and implies broad quest for prevention and treatment of disease. Studies have shown the participation of zinc in the synthesis, secretion and signaling pathway of insulin and the glucose control. This study aimed to analyze the mechanism of action of zinc in the control of insulin secretion and glucose control in order to understand whether supplementation with zinc prevents or delays the manifestation of DM2. The project was approved by CEUA-ICB (USP). Male mice C57BL/6 were divided en 4 groups: control diet (NFD); control diet supplemented with ZnCl2 (NFDZ); high fat diet (HFD); and high fat diet supplemented with ZnCl2 (HFDZ). Body weight, feed intake and water and the glucose levels were monitored weekly. Intraperitoneal glucose tolerance test (ipGTT) and insulin (ipITT) were performed at the 14th week of treatment. Completing the 15 weeks of the treatment glycemia, insulinemia and zincemia were analyzed, being applied HOMA-IR and HOMA-&#946; tests. In isolated islets was assessed the static insulin secretion at different glucose concentrations. The uptake and glucose metabolism test was done in the soleus muscle and the content analysis of the AKT and GSK3-&#946; protein was made in the soleus muscle and liver. The data (mean ± SEM) were analyzed by two-way ANOVA with Bonferoni post-test or Student\'s t test (P < 0,05). Zinc supplementation improves glucose dysfunction induced by high fat diet, without nonetheless affecting insulin resistance and insulin secretion by isolated islets

Zinc Supplementation Improves Glucose Homeostasis in High Fat-Fed Mice by Enhancing Pancreatic β-Cell Function

Zinc is an essential component of the insulin granule and it possibly modulates insulin secretion and signaling. Since insulin resistance is a hallmark in the development of type 2 diabetes mellitus, this study aimed at investigating if zinc supplementation is able to improve glucose tolerance and β-cell function in a model of insulin resistance. Male C57BL/6 mice were distributed in four groups according to the diet: normal fat (NF); normal fat supplemented with ZnCl2 (NFZ); high-fat (HF); and, high-fat chow supplemented with ZnCl2 (HFZ). Intraperitoneal glucose (ipGTT) and insulin (ipITT) tolerance, glycemia, insulinemia, HOMA-IR, and HOMA-β were determined after 15 weeks in each diet. Glucose-stimulated insulin secretion (GSIS) was investigated in isolated islets. The insulin effect on glucose uptake, metabolism, and signaling was investigated in soleus muscle. ZnCl2 did not affect body mass or insulin sensitivity as assessed by ipITT, HOMA-IR, muscle glucose metabolism, and Akt and GSK3-β phosphorylation. However, glucose tolerance, HOMA-β, and GSIS were significantly improved by ZnCl2 supplementation. Therefore, ZnCl2 supplementation improves glucose homeostasis in high fat-fed mice by a mechanism that enhances β-cell function, rather than whole-body or muscle insulin sensitivity

Chronic effect of blood orange juice intake on the microRNA expression profile and inflammatory response in overweight women

Introdução: A obesidade está diretamente envolvida na etiologia de doenças crônicas não transmissíveis (DCNT). A ingestão excessiva de nutrientes associada à obesidade culmina na ativação de vias de sinalização pró-inflamatórias em diferentes locais do organismo, acarretando uma inflamação sistêmica, crônica e de baixa intensidade. microRNA (miRNA) atuam como moduladores e biomarcadores de processos inflamatórios e a análise da sua expressão pode contribuir para identificação do risco de DCNT. A laranja (Citrus sinensis) é a fruta mais produzida no Brasil, contendo concentrações significantes de flavonoides, vitamina C e carotenoides, os quais apresentam atividade antioxidante e anti-inflamatória. Neste contexto, destaca-se a laranja sanguínea, que além dos compostos nutricionais comuns em Citrus, contem antocianinas. Objetivo: Investigar o efeito da ingestão crônica de suco de laranja sanguínea Moro sobre a resposta inflamatória e o perfil de expressão de miRNA no plasma e em células mononucleares do sangue periférico (PBMC) em mulheres com sobrepeso. Métodos: Estudo de intervenção crônica em mulheres (n = 20) de 18 a 40 anos, diagnosticadas com sobrepeso (índice de massa corporal = 25,0 a 29,9 kg/m2). Durante quatro semanas, as voluntárias ingeriram, diariamente, 500 mL de suco de laranja sanguínea Moro, com colheitas de sangue realizadas nos momentos basal e após 2 e 4 semanas do início do protocolo experimental. Foram realizadas as seguintes análises: caracterização do suco de laranja sanguínea Moro; avaliação antropométrica; aferição da pressão arterial; avaliação do consumo alimentar; determinação das concentrações plasmáticas de glicose, insulina, lipopolissacarídeos, proteína ligadora de lipopolissacarídeo, cluster de diferenciação 14 solúvel, biomarcadores inflamatórios [interleucina (IL)-6, IL-10, fator de necrose tumoral alfa (TNF-&alpha;), proteína quimiotática de monócitos-1, molécula de adesão intercelular solúvel (sICAM)-1 e a molécula de adesão celular vascular solúvel (sVCAM)-1]; e determinação das concentrações séricas do perfil lipídico, proteína C reativa, fibrinogênio, D-dímero, gama glutamil transferase, alanina aminotransferase, aspartato aminotransferase, amilase, ureia, creatinina e minerais. Foram também analisadas a expressão de miRNA no plasma e em PBMC; a expressão dos genes TNF, fator nuclear kappa B subunidade p50 (NFKB1), NF-&kappa;B subunidade p65 (RELA), inibidor alfa do NF-&kappa;B (NFKBIA), IL1, IL6, IL10, e receptores do tipo toll (TLR2 e TLR4); e o conteúdo e a fosforilação das proteínas NF-&kappa;B, I&kappa;B-&alpha;, quinase c-Jun N-terminal (JNK), quinase beta inibidora do I&kappa;B-&alpha; (IKK-&beta;) e fator de transformação de crescimento beta 1 (TAK1). Resultados: A ingestão do suco de laranja sanguínea Moro aumentou o consumo de vitamina C (p < 0,001), a razão fosfo-JNK/JNK (p < 0,05) e a expressão de miRNA no plasma [miR-144-3p (p = 0,02)] e em PBMC [miR-424-5p (p = 0,002), miR-144-3p (p = 0,006) e miR-130b-3p (p = 0,03)]. Por outro lado, diminuiu o conteúdo proteico de NF-&kappa;B (p < 0,05) e a expressão do let-7f-5p (p = 0,007) e do miR-126-3p (p = 0,04) em PBMC. Contudo, não foram observadas alterações significativas na expressão de genes que codificam proteínas envolvidas com a resposta inflamatória e nos parâmetros antropométricos e bioquímicos analisados ao final do protocolo experimental. Conclusão: A ingestão do suco de laranja sanguínea modula a expressão de miRNA em PBMC e no plasma e diminui o conteúdo proteico de NF-&kappa;B em PBMC, sem alterar a ingestão calórica, os parâmetros antropométricos e os biomarcadores metabólicos avaliados.Introduction: Obesity is directly involved in the etiology of chronic non-communicable diseases (NCD). The excessive intake of nutrients associated with obesity culminates in the activation of pro-inflammatory signaling pathways in different parts of the body, causing systemic, chronic, and low-intensity inflammation. microRNA (miRNA) act as modulators and biomarkers of inflammatory processes and the analysis of their expression can contribute to the identification of the risk of NCDs. Orange (Citrus sinensis) is the most produced fruit in Brazil, containing significant concentrations of flavonoids, vitamin C, and carotenoids, which have antioxidant and anti-inflammatory activity. In this context, blood orange stands out, which in addition to the common nutritional compounds in Citrus, it has anthocyanins. Objective: To investigate the effect of chronic Moro blood orange juice intake on the inflammatory response and miRNA expression profile in plasma and peripheral blood mononuclear cells (PBMC) in overweight women. Methods: Chronic intervention study in women (n = 20) aged 18 to 40 years old, diagnosed with overweight (body mass index = 25.0 to 29.9 kg/m2). For four weeks, the volunteers ingested, daily, 500 mL of Moro blood orange juice, with blood samples collected at baseline and 2 and 4 weeks after the beginning of the experimental protocol. The following analyses were carried out: characterization of Moro blood orange juice; anthropometric measurements; blood pressure measurement; dietary intake assessment; determination of plasma concentrations of glucose, insulin, lipopolysaccharides, lipopolysaccharide-binding protein, soluble cluster of differentiation 14, and inflammatory biomarkers [interleukin (IL)-6, IL-10, tumor necrosis factor-alpha (TNF-&alpha;), monocyte chemoattractant protein-1, soluble intercellular adhesion molecule (sICAM)-1 and soluble vascular cell adhesion molecule (sVCAM)-1]; and determination of serum concentrations of lipid profile, C-reactive protein, fibrinogen, D-dimer, gamma-glutamyl transferase, alanine aminotransferase, aspartate aminotransferase, amylase, urea, creatinine, and minerals. Were also analyzed the expression of miRNA in plasma and PBMC; the expression of genes TNF, nuclear factor kappa B p50 subunit (NFKB1), NF-&kappa;B p65 subunit (RELA), NF-&kappa;B inhibitor alpha (NFKBIA), IL1, IL6, IL10, and toll-like receptors (TLR2 e TLR4); and the content and phosphorylation of proteins NF-&kappa;B, I&kappa;B-&alpha;, c-Jun N-terminal kinase (JNK), inhibitor of NF-&kappa;B kinase subunit beta (IKK-&beta;) and transforming growth factor &beta;-activated kinase 1 (TAK1). Results: Moro blood orange juice intake increased vitamin C consumption (p < 0.001), phospho-JNK/JNK ratio (p < 0.05), and miRNA expression in plasma [miR-144-3p (p = 0.02)] and in PBMC [miR-424-5p (p = 0.002), miR-144-3p (p = 0.006), and miR-130b-3p (p = 0.03)]. Conversely, it decreased the protein content of NF-&kappa;B (p < 0.05) and the expression of let-7f-5p (p = 0.007) and miR-126-3p (p = 0.04) in PBMC. However, no significant changes were observed in the expression of genes that encode proteins involved in the inflammatory response and the anthropometric and biochemical parameters analyzed at the end of the experimental protocol. Conclusion: Ingestion of blood orange juice modulates miRNA expression in PBMC and plasma and decreases the protein content of NF-&kappa;B in PBMC, without changing caloric intake, anthropometric parameters, and metabolic biomarkers evaluated

Zinc Supplementation Improves Glucose Homeostasis in High Fat-Fed Mice by Enhancing Pancreatic β-Cell Function

Zinc is an essential component of the insulin granule and it possibly modulates insulin secretion and signaling. Since insulin resistance is a hallmark in the development of type 2 diabetes mellitus, this study aimed at investigating if zinc supplementation is able to improve glucose tolerance and β-cell function in a model of insulin resistance. Male C57BL/6 mice were distributed in four groups according to the diet: normal fat (NF); normal fat supplemented with ZnCl2 (NFZ); high-fat (HF); and, high-fat chow supplemented with ZnCl2 (HFZ). Intraperitoneal glucose (ipGTT) and insulin (ipITT) tolerance, glycemia, insulinemia, HOMA-IR, and HOMA-β were determined after 15 weeks in each diet. Glucose-stimulated insulin secretion (GSIS) was investigated in isolated islets. The insulin effect on glucose uptake, metabolism, and signaling was investigated in soleus muscle. ZnCl2 did not affect body mass or insulin sensitivity as assessed by ipITT, HOMA-IR, muscle glucose metabolism, and Akt and GSK3-β phosphorylation. However, glucose tolerance, HOMA-β, and GSIS were significantly improved by ZnCl2 supplementation. Therefore, ZnCl2 supplementation improves glucose homeostasis in high fat-fed mice by a mechanism that enhances β-cell function, rather than whole-body or muscle insulin sensitivity

Low Birth Weight Intensifies Changes in Markers of Hepatocarcinogenesis Induced by Fructose Consumption in Rats.

Peer reviewed: TrueFunder: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Intrauterine growth restriction (IUGR) due to fetal exposure to glucocorticoid excess results in metabolic inflexibility and hepatic steatosis upon nutritional stress during adulthood. We previously demonstrated that rats born to dexamethasone (DEX)-treated mothers developed hepatic steatosis when exposed to 10% fructose solution during adult life. Persistent triacylglyceride (TAG) accumulation in the liver, in turn, is a feature of non-alcoholic fatty liver disease (NAFLD), which serves as a risk factor for non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). In the present study, we demonstrate that the combination of IUGR and fructose treatment during adulthood also results in increased hepatic myeloperoxidase (MPO) activity, AKT phosphorylation and serum aspartate transaminase. Growth-restricted rats also presented reduced hepatic TRIB3 and GADD45a after fructose treatment. Other markers of cell proliferation, such as Cyclin D, PCNA, Hgf and Hspa4/Hsp70 expression and the number of Ki-67 positive cells, were all increased in the liver of growth- restricted rats treated with fructose. On the other hand, the combination of IUGR and fructose treatment during adult life reduced the levels of IGF-1. In conclusion, our data indicate that after exposure to fructose, adult rats subjected to dexamethasone-induced IUGR display exacerbated molecular changes in markers of NASH and HCC