Iranian Journal of

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Background: The myostatin/SMAD pathway is one of the most important regulatory pathways in heart muscle cells atrophy. Diabetes can disorder this pathway. Therefore, the aim of the present study was to evaluate the effect of six weeks of endurance training on the content myostatin and SMAD2/3 proteins in the left ventricular tissue of the heart muscle of type 1 diabetic rats.
Methods: In this study, 12 head 2-month-old male Sprague-Dawley male rats with a mean weight of 300±20 g were selected. After induction of diabetes through streptozotocin solution, they were randomly divided into 2 groups: diabetic endurance training (6 heads) and diabetic control (6 heads); The training groups performed the training program 4 days a week for 6 weeks, including 32 minutes of endurance training with an intensity of about 50 to 70% of the maximum speed; SPSS software version 23 and independent t-test were used to analyze the data. Significance level was considered p≤0.05.
Findings: Endurance training resulted in a significant decrease in myostatin (P=0.024) and SMAD2/3 (P=0.001) proteins content between training and control groups in myocardial tissue.
Conclusion: It can be said that endurance training by reducing the content of myostatin and SMAD2/3 proteins in the left ventricle of the heart may have been able to prevent cardiac atrophy in type 1 diabetic subjects. This reduction can lead to physiological cardiac hypertrophy.

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Background: AMPK and P53 proteins regulate the TOR protein in the TORC1 complex, which regulates many physiological processes. The aim of this study was to evaluate the effect of AMPK and P53 proteins on the TOR pathway following endurance training in the left ventricle of the heart of diabetic rats by streptozotocin and nicotinamide.
Methods: In this experimental study, 12 head two-month-old Sprague-Dawley rats with a mean weight of 270±20 g were selected. After diabetic induction with streptozotocin and Nicotinamide, rats were randomly assigned to two groups, training and control (6 heads in group each). The training group performed endurance training on a treadmill for rodents for 6 weeks and 4 sessions per week for 42 minutes with an intensity of about 50 to 70% of the maximum speed. SPSS software version 23 and independent t-test were used to analyze the data.
Results: Six weeks of endurance training led to significant increase in the protein content of AMPK (P=0.009) and TOR (P=0.005) between training and control groups in the left ventricular tissue of the heart muscle. In contrast, a significant decrease in P53 protein content was observed between the training and control groups in the left ventricular tissue of the heart muscle (P=0.0001).
Conclusion: The results showed that endurance training can with increase the content of AMPK and TOR proteins and decrease the content of P53 protein to regulate processes such as metabolism, mitochondrial biogenesis, cardiac hypertrophy, inhibition of autophagy in the hearts of diabetic subjects.