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Physical exercise is considered a fundamental strategy in improving insulin sensitivity and glucose uptake in skeletal muscle. However, the molecular mechanisms underlying this regulation, primarily on skeletal muscle glucose uptake, are not fully understood. Recent evidence has shown that Rho-kinase (ROCK) isoforms play a pivotal role in regulating skeletal muscle glucose uptake and systemic glucose homeostasis. The current study evaluated the effect of physical exercise on ROCK2 signaling in skeletal muscle of insulin-resistant obese animals. Physiological (ITT) and molecular analysis (immunoblotting, and RT-qPCR) were performed. The contents of RhoA and ROCK2 protein were decreased in skeletal muscle of obese mice compared to control mice but were restored to normal levels in response to physical exercise. The exercised animals also showed higher phosphorylation of insulin receptor substrate 1 (IRS1 Serine 632/635) and protein kinase B (Akt) in the skeletal muscle. However, phosphatase and tensin homolog (PTEN) and protein-tyrosine phosphatase-1B (PTP-1B), both inhibitory regulators for insulin action, were increased in obesity but decreased after exercise. The impact of ROCK2 action on muscle insulin signaling is further underscored by the fact that impaired IRS1 and Akt phosphorylation caused by palmitate in C2C12 myotubes was entirely restored by ROCK2 overexpression. These results suggest that the exercise-induced upregulation of RhoA-ROCK2 signaling in skeletal muscle is associated with increased systemic insulin sensitivity in obese mice and further implicate that muscle ROCK2 could be a potential target for treating obesity-linked metabolic disorders.

Background: Green tea, obtained from the plant Camellis sinensis, is one of the oldest drinks in the world and contains numerous bioactive compounds. Studies have demonstrated the efficacy of green tea in preventing obesity and cardiovascular diseases that may be related to the reduction of lipid levels. Aim: This study aimed to evidence, through a systematic review, the therapeutic potential of green tea on the lipid profile in preclinical studies in obese animals and clinical studies in obese individuals. Methods: This systematic review follows the recommendations of the preferred report items for systematic reviews and meta-analyses. The electronic databases, PubMed (Medline), Science Direct, Scopus, and Web of Science were consulted. Articles from January 2009 to December 2019 were selected. Results: This search resulted in twenty-nine articles were included cirtically reviewed. In experimental studies, green tea administration has been shown to reduce total cholesterol, triglycerides and low-density lipoprotein cholesterol in animals exposed to obesity-inducing diet. In humans’ studies green tea was not shown to be effective for obese lipid control. Because supplementation with green tea extract reduced total cholesterol, triglycerides, low-density lipoprotein for three months at a specific dose. Conclusion: Therefore, green tea appears to act as a protective agent for dyslipidemia in obesity-induced animals. In human studies, green tea has not been shown to be effective in controlling obese lipids.

Aim This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p <0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.