23 research outputs found

    Hypothalamic S1P/S1PR1 axis controls energy homeostasis

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    Sphingosine 1-phosphate receptor 1 (S1PR1) is a G-protein-coupled receptor for sphingosine-1-phosphate (S1P) that has a role in many physiological and pathophysiological processes. Here we show that the S1P/S1PR1 signalling pathway in hypothalamic neurons regulates energy homeostasis in rodents. We demonstrate that S1PR1 protein is highly enriched in hypothalamic POMC neurons of rats. Intracerebroventricular injections of the bioactive lipid, S1P, reduce food consumption and increase rat energy expenditure through persistent activation of STAT3 and the melanocortin system. Similarly, the selective disruption of hypothalamic S1PR1 increases food intake and reduces the respiratory exchange ratio. We further show that STAT3 controls S1PR1 expression in neurons via a positive feedback mechanism. Interestingly, several models of obesity and cancer anorexia display an imbalance of hypothalamic S1P/S1PR1/STAT3 axis, whereas pharmacological intervention ameliorates these phenotypes. Taken together, our data demonstrate that the neuronal S1P/S1PR1/STAT3 signalling axis plays a critical role in the control of energy homeostasis in rats

    Central Exercise Action Increases the AMPK and mTOR Response to Leptin

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    AMP-activated protein kinase (AMPK) and mammalian Target of Rapamycin (mTOR) are key regulators of cellular energy balance and of the effects of leptin on food intake. Acute exercise is associated with increased sensitivity to the effects of leptin on food intake in an IL-6-dependent manner. To determine whether exercise ameliorates the AMPK and mTOR response to leptin in the hypothalamus in an IL-6-dependent manner, rats performed two 3-h exercise bouts, separated by one 45-min rest period. Intracerebroventricular IL-6 infusion reduced food intake and pretreatment with AMPK activators and mTOR inhibitor prevented IL-6-induced anorexia. Activators of AMPK and fasting increased food intake in control rats to a greater extent than that observed in exercised ones, whereas inhibitor of AMPK had the opposite effect. Furthermore, the reduction of AMPK and ACC phosphorylation and increase in phosphorylation of proteins involved in mTOR signal transduction, observed in the hypothalamus after leptin infusion, were more pronounced in both lean and diet-induced obesity rats after acute exercise. Treatment with leptin reduced food intake in exercised rats that were pretreated with vehicle, although no increase in responsiveness to leptin-induced anorexia after pretreatment with anti-IL6 antibody, AICAR or Rapamycin was detected. Thus, the effects of leptin on the AMPK/mTOR pathway, potentiated by acute exercise, may contribute to appetite suppressive actions in the hypothalamus

    TRY plant trait database – enhanced coverage and open access

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    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    PREPARATION OF PERCENTILE TABLES THROUGH ANTHROPOMETRIC, PERFORMANCE, BIOCHEMICAL, HEMATOLOGICAL, HORMONAL AND PSYCHOLOGICAL PARAMETERS IN PROFESSIONAL SOCCER PLAYERS

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    Introduction: The lack of reference values of anthropometric, performance, biochemical, hematological, hormonal and psychological parameters is an important limitation in the investigations with soccer players. Objective: To elaborate percentile tables to be used as comparison reference for further studies. Methods: 82 professional soccer players were evaluated approximately 30 days after the beginning of the main competition played by their teams. On the first day of evaluation, fast blood samples were collected for measurement of hematological parameters (i.e. erythrocytes, hemoglobin, hematocrit, mean corpuscular volume - MCV, mean corpuscular hemoglobin - MCH, mean corpuscular hemoglobin concentration - MCHC, leukocytes, eosinophils, lymphocytes, monocytes and platelets) and of concentrations of adrenaline, cortisol, creatine kinase, creatinine, norepinephrine, testosterone and urea. Subsequently, the soccer players had their anthropometric characteristics and psychological parameters assessed. In addition, the evaluation of the lactic anaerobic system efficiency was performed on a 400-m track. On the second day, both the alactic anaerobic and aerobic system efficiency was measured. Results: The percentile distribution (P-0, P-15, P-30, P-50, P-70, P-85 e P-100) was used to present the results. Conclusion: The elaboration of the percentile tables can be used as comparison reference for further studies.18314815

    Moderate Exercise Reduces Food Consumption in Obese Mice for Activate Jak-2/Stat-3 Pathway in the Hypothalami

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    It is very known that due to inflammatory processes the obesity leads to resistance to leptin, it reduces phosphorylation via JAK-2/STAT-3, which generates lower STAT-3 activity in the cell nucleus, and it leads to decrease the number of transcription of anorexigenic neurons (POMC/CART) and allowing transcription of orexigenic (NPY/AgRP). PURPOSE: The present study aimed to evaluate the effects of moderate aerobic training on food intake of obese mice through analysis of activity of hypothalamic proteins JAK-2/STAT-3. METHODS: It were used 30 Swiss mice (30 days old) divided into 3 groups: Control Group (C): sedentary animals fed with balanced diet ; Obese (OB) sedentary animals fed with high-fat diet throughout the experiment and Trained Obese (TOB) : animals fed with high fat diet throughout the experiment , kept sedentary during the first half of the experiment (8 weeks) and submitted to physical training protocol during the second half of the experiment (8 weeks). The exercise program consisted of treadmill running 1h, 5 days/week during 8 weeks at a speed equivalent to 60 % of maximum potency determined at the beginning of training period. To assess the leptin resistance, after rats were deprived of food for 6h with free access to water, they received i.p injection with leptin (2.0”l, 10-6M), after this, the chow was returned and food intake was determined by measuring the quantity and Kcal consumed at the end of 2h. The hypothalami was removed for determination of JAK-2 and STAt-3 activity. RESULTS: Our results showed that moderate physical exercise was effective in improving the JAK/STAT signaling pathway in the hypothalamus of obese animals. This has made these obese animals had reduced food intake and consequently lower body mass gain. CONCLUSION: It can be concluded that physical exercise, for restoring leptin signaling in the hypothalamus, controls the synthesis of neurons responsible for appetite and thus is an important tool in the treatment of obesity

    Reynolds number effects on low-speed aerodynamics of a hypersonic configuration

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    Objective To investigate the effects of a specific protocol of undulatory physical resistance training on maximal strength gains in elderly type 2 diabetics. Methods The study included 48 subjects, aged between 60 and 85 years, of both genders. They were divided into two groups: Untrained Diabetic Elderly (n=19) with those who were not subjected to physical training and Trained Diabetic Elderly (n=29), with those who were subjected to undulatory physical resistance training. The participants were evaluated with several types of resistance training’s equipment before and after training protocol, by test of one maximal repetition. The subjects were trained on undulatory resistance three times per week for a period of 16 weeks. The overload used in undulatory resistance training was equivalent to 50% of one maximal repetition and 70% of one maximal repetition, alternating weekly. Statistical analysis revealed significant differences (p<0.05) between pre-test and post-test over a period of 16 weeks. Results The average gains in strength were 43.20% (knee extension), 65.00% (knee flexion), 27.80% (supine sitting machine), 31.00% (rowing sitting), 43.90% (biceps pulley), and 21.10% (triceps pulley). Conclusion Undulatory resistance training used with weekly different overloads was effective to provide significant gains in maximum strength in elderly type 2 diabetic individuals.Objetivo Verificar os efeitos de um protocolo de treinamento fĂ­sico resistido ondulatĂłrio nos ganhos de força mĂĄxima em idosos diabĂ©ticos do tipo 2. MĂ©todos Participaram do estudo 48 indivĂ­duos, com idade entre 60 e 85 anos, de ambos os gĂȘneros. Eles foram divididos em dois grupos: Idosos DiabĂ©ticos NĂŁo Treinados (n=19), com aqueles nĂŁo submetidos ao treinamento fĂ­sico, e Idosos DiabĂ©ticos Treinados (n=29), que foram submetidos ao protocolo de treinamento fĂ­sico resistido ondulatĂłrio. Os idosos foram avaliados em diversos equipamentos de musculação, antes e apĂłs o treinamento resistido ondulatĂłrio, por meio do teste de uma repetição mĂĄxima. Os participantes realizaram o treinamento resistido ondulatĂłrio trĂȘs vezes por semanas, durante um perĂ­odo de 16 semanas. A sobrecarga do programa foi alternada, sendo em 1 semana equivalente a 50% de uma repetição mĂĄxima e, na outra semana, a 70% de uma repetição mĂĄxima. A anĂĄlise estatĂ­stica revelou diferenças significativas (p<0,05) entre os resultados dos testes prĂ© e pĂłs-perĂ­odo de treinamento resistido ondulatĂłrio em um perĂ­odo de 16 semanas. Resultados Os ganhos mĂ©dios de força foram de 43,20% (extensĂŁo de joelho), 65,00% (flexĂŁo de joelho), 27,80% (supino sentado mĂĄquina), 31,00% (remada sentado), 43,90% (bĂ­ceps pulley) e 21,10% (trĂ­ceps pulley). ConclusĂŁo O protocolo de treinamento resistido ondulatĂłrio utilizado com sobrecargas semanais diferentes foi eficiente em proporcionar significativos ganhos de força mĂĄxima em idosos diabĂ©ticos do tipo 2

    Cerebellar Insulin/IGF-1 signaling in diabetic rats: Effects of exercise training

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    The Diabetes Mellitus (DM) is a chronic disease associated with loss of brain regions such as the cerebellum, increasing the risk of developing neurodegenerative diseases such as Parkinson's disease (PD). In the brain of diabetic and PD organisms the insulin/IGF-1 signaling is altered. Exercise training is an effective intervention for the prevention of neurodegerative diseases since it release neurotrophic factors and regulating insulin/IGF-1 signaling in the brain. This study aimed to evaluate the proteins involved in the insulin/IGF-1 pathway in the cerebellum of diabetic rats subjected to exercise training protocol. Wistar rats were distributed in four groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD) and trained diabetic (TD). Diabetes was induced by Alloxan (ALX) (32 mg/kg b.w.). The training program consisted in swimming 5 days/week, 1 h/day, during 6 weeks, supporting an overload corresponding to 90% of the anaerobic threshold. At the end, cerebellum was extracted to determinate the protein expression of GSK-3 beta, IR beta and IGF-1R and the phosphorylation of beta-amyloid, Tau, ERK1 + ERK2 by Western Blot analysis. All dependent variables were analyzed by one-way analysis of variance with significance level of 5%. Diabetes causes hyperglycemia in both diabetic groupshowever, in TD, there was a reduction in hyperglycemia compared to SD. Diabetes increased Tau and beta-amyloid phosphorylation in both SD and TD groups. Furthermore, aerobic exercise increased ERK1 + ERK2 expression in TC. The data showed that in cerebellum of diabetic rats induced by alloxan there are some proteins expression like Parkinson cerebellum increased, and the exercise training was not able to modulate the expression of these proteins. (C) 2016 Elsevier Ireland Ltd. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Sao Paulo Fed Univ UNIFESP, Dept Biosci, Silva Jardim St 136, Santos, SP, BrazilUniv Estadual Campinas, UNICAMP, Sport Sci Course, Limeira, SP, BrazilSao Paulo State Univ UNESP, Dept Phys Educ, Rio Claro, SP, BrazilCatholic Univ, Ctr Unisalesiano, Dept Phys Educ, Lins, SP, BrazilUniv Ctr Patos De Minas, Dept Phys Educ, Patos De Minas, MG, BrazilSao Paulo Fed Univ UNIFESP, Dept Biosci, Silva Jardim St 136, Santos, SP, BrazilFAPESP: 2010/18257-0CNPq: 142587/2007-9Web of Scienc
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