Influência do treinamento resistido na expressão proteica do trânsito de cálcio intracelular miocárdico de ratos obesos

• Autor(a) principal: Damiani, Andressa Prata Leite
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/10191
• topic: Obesity; Myocardial calcium handling; Resistance training; Obesidade; Trânsito de cálcio miocárdico; Treinamento resistido; Ratos; Nutrição

Introduction: Obesity is considered a chronic metabolic disease of multifactorial origin characterized by excessive accumulation of adipose mass that can lead to cardiac damages such as morphological and functional changes. The functional alterations are related to the homeostatic imbalance of the proteins involved in calcium handling, an important mechanism responsible for the regulation of contractility and relaxation of the heart. In an attempt to minimize and/or reverse cardiac changes observed in the pathological condition of obesity, nonpharmacological strategy such as physical exercise have been used. Resistance training (RT) has been reported for benefits in improving body composition and cardiac function. However, the relationship between obesity, RT and calcium handling still needs to be clarified and better understood. Objective: To evaluate the effect of RT on the protein expression of calcium handling in obese rats, besides analyzing the biomarkers of morbidities associated with obesity. Methods: Wistar rats were induced and exposed to the condition of obesity and later redistributed in sedentary groups and submitted to RT: Control (C, n = 10), Obese (Ob, n = 9), Control submitted to resistance training (Ctr, n = 11) and Obese submitted to resistance training (Obtr, n = 11). The control groups received standard diet and the obese groups hyperlipidic diet. The ladder RT protocol was performed for 10 weeks, with frequency of 3 days a week. The training consisted of 4 to 5 series with progressive intensities of 50%, 75%, 90% and 100% of the maximum load (ML), at the end of the 4th grade, the animal was submitted to 5th grade with 100% ML + 30g. The analysis of the nutritional, blood pressure, glycemic, lipid, and hormonal profile and determination of the water content in cardiac, pancreatic, pulmonary and hepatic tissue were performed. In addition, the total weight of the heart, left and right ventricles, atriums and their respective relationships with tibial length, as well as the cross sectional area, myocardial collagen, and protein regulatory expression of calcium handling were analyzed by Western Blot technique. Parametric data were expressed as mean ± standard deviation and the nonparametric in median ± interquartile range. The comparisons between groups C and Ob were performed by Test t. For the comparisons between groups C, Ob, Ctr and Obtr two-way ANOVA was used and complemented with Bonferroni post hoc test. The level of significance was 5%. Results: The main findings were the frequently comorbidities seen in the condition of obesity, hypertriglyceridemia and hyperleptinemia. In addition, in the process of cardiac remodeling, despite the absence of hypertrophy, obesity led to an increase in the deposition of myocardial collagen and expression of pPLBser16 and pPLB/PLB reduced. The reversals from RT were expressed by reduction of body weight and fat, adiposity index, plasmatic triglycerides and leptin. Conclusion: The RT was not able to reverse the pPLBser16 impairment in the obesity condition. However, it represented a relevant non-pharmacological treatment in the improvement of body composition and the biomarkers of obesity, expressed by the reduction of body weight and fat, adiposity index and plasma triglycerides and leptin levels.