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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) (32mg/kgb.w.). The training program consisted in swimming 5days/week, 1h/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-3ß, IRß and IGF-1R and the phosphorylation of ß-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 groups; however, in TD, there was a reduction in hyperglycemia compared to SD. Diabetes increased Tau and ß-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.

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INTRODUÇÃO: A prática de exercícios de intensidade moderada pode reduzir o risco de infecções e melhorar os aspectos metabólicos do indivíduo. OBJETIVO: Investigar os efeitos do treinamento físico aeróbio sobre os aspectos metabólicos, ósseo e sistema imunológico. MÉTODOS: Vinte ratos machos, recém-desmamados, foram distribuídos em dois grupos experimentais: grupo sedentário (GS) e grupo treinado (GT). O GT foi submetido a um protocolo de natação, durante seis semanas consecutivas. Ao final do período experimental, foi realizada a contagem total e diferencial de leucócitos e hematócrito. Após o sacrifício, foram analisados: glicose, proteínas totais, triglicérides, colesterol; amostras do fígado e músculo para a determinação dos teores de glicogênio; e tíbia para determinação do comprimento e área óssea. Os dados foram analisados pela análise de variância ANOVA one-way e o nível de significância estabelecido foi p<0,05. RESULTADOS: O hematócrito (%) analisado apresentou diferença significativa, com maior valor para o GT (54,63 ± 1,41) que para o GS (49,5 ± 1,65). A contagem total de leucócitos não apresentou diferença significativa, assim como também não houve diferença na contagem diferencial. O colesterol total apresentou relevante diminuição no GT (GT = 68,27 ± 13,71 mg/dL; GS = 94,44 ± 28,09); os níveis de proteínas totais também apresentaram importante redução (GT = 7,3 ± 0,40 g/dL; GS = 7,74 ± 0,36 g/dL); os níveis de glicose e triglicérides não apresentaram diferenças significativas. Já o comprimento ósseo apresentou diferença significativa, com o comprimento do tibial do GT (40 ± 0,14* mm) sendo menor que o GC (42,10 ± 0,12 mm). A área tibial demonstrou menor valor para o GT (1,53 ± 0,12 cm²) que para o GS (1,67 ± 0,18 cm²), entretanto, a diferença não foi estatisticamente significante. CONCLUSÃO: O treinamento físico aeróbio é capaz de produzir algumas modificações fisiológicas peculiares em ratos jovens.

INTRODUCTION: The practice of moderate-intensity exercise can reduce the risk of infections and improve metabolic aspects of the person. OBJECTIVE: To investigate the effects of aerobic physical training on endocrine and metabolic aspects, bone and immune system. METHODS: Twenty Wistar rats were divided in two groups: sedentary (GS) and trained group (TG). Training program consisted in swimming, 6 weeks, supporting a workload corresponding to 5% of body weight. At the end of the experiment, were performed counting total and differential leukocyte count and hematocrit. After training period, were analyzed glucose, total protein, triglycerides, cholesterol, liver and muscle samples for the determination of the levels of glycogen, and determination of the tibia length and bone area. All dependent variables were analyzed by one-way analysis of variance (ANOVA) and a significance level of P < 0.05 was used for all comparisons. RESULTS: Hematocrit (%) analyzed showed a significant difference, with higher values ​​for TG (54.63 ± 1.41) than for the GS (49.5 ± 1.65). The total leukocyte count was not significantly different, as there was no difference in the differential count. Total cholesterol showed significant decrease in GT (GT = 68.27 ± 13.71 mg/dL; GS = 94.44 ± 28.09), the total protein levels also showed significant reduction (GT = 7.3 ± 0,40 g/dL; GS = 7.74 ± 0.36 g/dL) glucose levels and triglyceride showed no significant differences.The bone length showed a significant difference (GT = 40±0.14 mm; CG = 42.10 ± 0.12mm). The tibial area showed the lowest value for the GT (1.53 ± 0.12cm²) than for the GS (1.67 ± 0.18cm²) however the difference was not statistically significant. CONCLUSION: It can be concluded that aerobic exercise training is able to produce some unique physiological changes in young rats. There is also the need to prescribe exercises that meet the particular maturational stage of development.

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UNLABELLED: Brain insulin has had widespread metabolic, neurotrophic, and neuromodulatory functions and has been involved in the central regulation of food intake and body weight, learning and memory, neuronal development, and neuronal apoptosis. PURPOSE: The present study investigated the role of swimming training on cerebral metabolism on insulin concentrations in cerebellum and the body balance performance of diabetic rats. METHODS: Forty Male Wistar rats were divided in four groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD), and trained diabetic (TD). Diabetes was induced by alloxan (32mgkg b.w.), single dose injection. The mean blood glucose of diabetic groups was 367±40mg/dl. Training program consisted in swimming 5days/week, 1h/day, 8weeks, supporting a workload corresponding to 90% of maximal lactate steady state (MLSS). For the body balance testing rats were trained to traverse for 5min daily for 5-7days. All dependent variables were analyzed by one-way analysis of variance (ANOVA) and a significance level of p<0.05 was used for all comparisons. RESULTS: The body balance testing scores were different between groups. Insulin concentrations in cerebellum were not different between groups. CONCLUSION: It was concluded that in diabetic rats, aerobic training does not induce alterations on cerebellum insulin but induces important metabolic, hormonal and behavioral alterations which are associated with an improvement in glucose homeostasis, serum insulin concentrations and body balance.

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INTRODUÇÃO: Evidências apontam que a ingestão exacerbada de frutose pode desencadear distúrbios característicos da síndrome metabólica. OBJETIVOS: Analisar os efeitos da ingestão de dieta rica em frutose sobre aspectos metabólicos de ratos da linhagem Wistar. Adicionalmente, verificar a capacidade aeróbia através da identificação da máxima fase estável de lactato (MFEL). MÉTODOS: Dezesseis ratos foram separados em dois grupos de oito animais: a) controle, alimentados com dieta balanceada, e b) frutose, alimentados com dieta rica em frutose. Foram analisadas a tolerância à glicose (área sob a curva de glicose durante teste de tolerância à glicose), sensibilidade à insulina (taxa de remoção da glicose sérica após sobrecarga exógena de insulina), perfil lipídico sérico e concentração de lactato sanguíneo [lac]s durante exercício na intensidade da MFEL. RESULTADOS: Teste t não pareado (p < 0,05) revelou diferença para a tolerância à glicose e triglicérides, porém não houve diferença na sensibilidade à insulina e na [lac]s. Anova one way com post hoc de Newman-Keuls (p < 0,05) revelou diferença para a cinética da glicose durante o teste de tolerância, mas não para a cinética do lactato durante exercício na MSSL. CONCLUSÃO: As Alterações fisiológicas provocadas pela dieta rica em frutose e inerentes à síndrome metabólica não prejudicam a capacidade aeróbia de ratos.

INTRODUCTION: Evidence points that exacerbated ingestion of fructose may trigger disturbs characteristic of the metabolic syndrome. OBJECTIVES: To analyze the effects of a fructose rich diet on metabolic aspects of Wistar lineage rats. Additionally, to verify the aerobic capacity, through the identification of the maximal lactate steady state (MSSL). PROCEDURES: Sixteen rats were separated in two groups of eight animals: a) Control, fed a balanced diet, and b) fructose, fed a fructose-rich diet. The glucose tolerance, (area under serum glucose during a glucose tolerance test), insulin sensibility (glucose disappearance rate after exogenous insulin administration), serum lipid profile and blood lactate concentration [lac]b during exercise at MSSL intensity, have been analyzed. RESULTS: Non-paired t test (p<0.05) revealed difference between groups in the area under the curve of glucose and serum triglycerides, no difference in insulin sensibility or in [lac]b was detected, though. One-way ANOVA with Newman Keuls post hoc revealed difference in the glucose kinetics during tolerance test, but not in the lactate kinetics during the MSSL. CONCLUSION: The physiological alterations promoted by fructose-rich diet and intrinsic to the metabolic syndrome do not harm the aerobic capacity of rats.

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