THE EFFECT OF 8 WEEKS AEROBIC TRAINING ON CARDIAC PGC-1Α AND PLASMA IRISIN IN STZ-INDUCED DIABETICS’ RATS

Background: Cardiomyopathy is one of adverse effects of diabetes that associated with cardiac muscle metabolism and function disruption. Exercise training decreases adverse effects of diabetes on heart by changing genes involved in cardiac metabolism and increasing myokines secretion. So, the aim of this study was to investigate of 8 weeks aerobic training on cardiac PGC-1α gene expression and plasma irisin in STZ-induced diabetics’ rats. Methods: 16 STZ-induced diabetics Wistar rats (10 weeks old) divided into control and aerobic training groups. Time and intensity of exercise session began with 15 minutes and 10 m/min, and gradually increased to 40 minutes and 25 m/min at seventh week and kept to the end of eighth’s week (8 weeks). Cardiac PGC-1α gene expression analyzed by PCR, and plasma concentration of insulin, glucose were analyzed by ELISA method 48 hours after the last session of exercise training. Data were analyzed by independent t test at alpha level of 0/05. Results: the results showed that aerobic exercise training increased PGC-1α concentration (P<0/001) and plasma irisin (P<0/001). Further analysis showed that aerobic exercise training decreased glucose concentration (P<0/001) and increased insulin concentration (P<0/001), but had no effect of insulin resistance (P=0/79). In addition, the results revealed that there is a positive correlation between PGC-1α and plasma irisin (P<0/001) and insulin (P=0/019), but it has a negative correlation with plasma glucose (P=0/001). There is also a positive significant correlation between isirin and insulin (P=0/001), and a negative correlation between irisin and glucose (P=0/002). Conclusion: The findings suggest that aerobic exercise training induces increased cardiac PGC-1α gene expression and plasma irisin. These changes have a significant correlation with lowered glucose and increased plasma insulin insulin in STZ-induced diabetics’ rats.