he Effect of Aerobic Exercise on Gene Expression of Hepatocyte Nuclear Factor-4α (HNF-4α) and Insulin Resistance in Type 2 Diabetic Rats

The aim of this study was to investigate the effect of aerobic exercise on the gene expression of hepatocyte nuclear factor-4α (HNF-4α), glucose, insulin and insulin resistance in type 2 diabetic rats. For this purpose, 20 male 10-week-old male rats (weight 20±220 gr) were selected. Type 2 diabetes was induced intraperitoneally by the injection of nicotinamide-streptozotocin and then were randomly divided into two groups of aerobic exercise and control. The aerobic exercise program was performed for 12 weeks, 5 sessions a week, 10-50 minutes per session and speed of 18-26 meter/minute. Fasting glucose, serum insulin and HNF-4α gene expression in the liver tissue were measured in both groups after the last exercise session and compared by independent t test. The results showed that aerobic exercise significantly decreased fasting glucose (P=0.001), insulin resistance (P=0.044) and significantly increased insulin (P=0.019). Also, the expression of HNF-4α after aerobic exercise significantly decreased in comparison with the control group (P=0.007). Based on these findings, aerobic exercise is likely to reduce the liver HNF-4α gene expression of type 2 diabetic rats by increasing serum insulin. Thus, reduced expression of this gene through the effect of aerobic exercise and thereby reduced production of liver glucose may be one of the mechanisms of the effect of exercise in people with type 2 diabetes.