The Effects Of Endurance Training On The Genic Expression Of Mfn1, Mfn2 And PGC-1α In GK Rat Skeletal Muscle

Mitochondrial dysfunction has been reported in skeletal muscle of type 2 diabetic patients. Reduced mitochondrial mass and defective activity have been proposed to explain this dysfunction. Alterations in mitochondrial function may be crucial to explain the metabolic changes and insulin resistance that characterize of type 2 diabetes. As the most important organelle of the cell, mitochondria undergo frequent fusion and fission, and the balance of these opposing processes regulates mitochondrial morphology. Several functions of the mitochondria fusion protein Mitofusin have been found, such as promoting mitochondria fusion, inhibiting cell proliferation and protecting cell against apoptosis. More and more evidence suggest that it is involved in insulin counteraction. Exercise can cause adaptive alteration of mitochondrial biogenesis in skeletal muscle. Exercise has always been of concern in prevention and treatment of type 2 diabetes. It is very significantly to type 2 diabetes training that Researches on proteins of mRNA relative to mitochondrial fusion in endurance training Induced Situations.Objective:To investigate the effects of endurance training on blood glucose, serum adiponectin, plasma insulin levels, and the genie expresstion Mfnl, Mfn2 and PGC-1αin GK rats skeletal muscle.Methods:Total 12 male GK rats were randomly divided into two groups which include control group (H),endurance training group (R). There are 6 rats in each group. R groups were trained on the treadmill for 6 weeks.6 times a week, in the first week they exercise 30 minutes every time, in the second week hey exercise 40 minutes every time, in the third week hey exercise 50 minutes every time, and the last three weeks, they exercise 60 minutes every time. The rats were killed in the time during 24～48 hours after the last time exercise. Detected the blood glucose and plasma insulin levels in each group, the situation of insulin resistance were reflected by insulin resistance index. mRNA levels of Mfnl, Mfn2 and PGC-1αof GK rats' skeletal muscle were determined using real-time quantitative PCR (RT-Q-PCR). Results:(1)Endurance training obviously decreased GK rats's the level of blood glucose, insulin and insulin resistance index, increased the level of insulin serum adiponectin, but have not an effection on to increased rats's body weight growth rate.(2)Endurance training did not induce a significant change of Mfn1mRNA levels in GK rats's skeletal muscles(P>0.05).(3)Endurance training obviously increased rats's the level of Mfn2mRNA levels in GK rats's skeletal muscles(P<0.05).(4)Endurance training obviously decreased GK rats's the level of PGC-1αmRNA levels in rats's skeletal muscles(P<0.05).Conclusions:(1)Endurance training can improve the body's insulin sensitivity, decrease the level of blood glucose and increase the level of serum adiponectin, shows that endurance training have a positive impact on IR of GK rats.(2)Mfn2 and PGC-1 a join in the improvement done by the endurance training toward Type 2 diabetes, and the mitochondrial fusion mediated by Mfn2 may play an active role in the enhancement of the Type 2 Diabetes.