| Diabetes is a series of metabolic disorder syndrome induced by a variety of pathogenic factors acting on the body leading to islet dysfunction and insulin resistance,and metabolic disorder of glucose,protein,fat,water and electrolytes. It's also one of the diseases with highest morbidity and mortality. Insulin resistance and diabetes are closely linked, in type 2 diabetes patients, up to 90% of the body there were symptoms of insulin resistance. The the improvement of insulin resistance index could be caused either by the acquired a high-fat diet or the congenital genetic diabetes.The long-term endurance exercise can promote the biosynthesis of mitochondria,improve mitochondrial function,not only can alleviate the negative effects of High-fat diet on the body, but also have a positive improvement in the diabetic patients.PGC-1αis a transcriptional co-activator factor in vivo,and plays an important role in the regulation of in the transformation of muscle fiber type, glucose metabolism, fatty acid oxidation and mitochondrial biosynthesis; ERRa is an important effect device of PGC-la when activated by PGC-1α,ERRa would expand the cascade effect of PGC-1α, so it Also plays an important role in the body energy metabolism and mitochondrial bio-synthesis;NRF-2, which mediated by PGC-1αand ERRa, regulates the expression of important transcription regulatory protein factor in the respiratory chain. When are stimulated, PGC-la-ERRa-NRF-2 pathway may induce the biosynthesis of mitochondria to generate adaptive stress, in order to maintain the body's health.Objective:The aim of this study was to investigate the effects of endurance training on the expression of PGC-la,ERRa, NRF-2 genes in the high-fat diet rats, as well as GK rats' skeletal muscle;the effects of endurance exercise on the body's biological synthesis, the high-fat diet bodys'insulin resistance, and the effect on congenital diabetes disease.Methods:The 40 male SD rats,about 4 weeks old,weighing 100±5g were randomly divided into SD normal diet control group (C),SD ordinary diet endurance training group(E),SD high-fat diet the control group (H) and SD high-fat diet endurance training group (HE), n=10 each group;At the same time 12 GK male rats, about 8 weeks of age, weighing 250±5g were randomly divided into GK control group (G), and GK endurance exercise group (GE),n=6 each group.SD endurance exercise rats take 8 weeks of treadmill training, while GK endurance exercise rats take 6 weeks, training six days a week, starting with a speed of of 13m/min, a maximum speed of no more than 16.7m/min.At first, SD endurance exercise rats takes four weeks training 40 minutes a day training, then takesl h/day training for four weeks.GK endurance exercise rats take a 30 minutes'training at the first week, then in the next two weeks, the training time gradually adds to 60 minutes and keeps for 3weeks.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 PGC-1α,ERRa and NRF-2 of rats'skeletal muscle were determined using real-time PCR.Results:(1)Body Weight:High-fat diet can significantly improve the body weight.Endurance exercise can effectly control the weight gain caused by high-fat diet, but don't have significantly effect on the GK rats'weight-gainning.(2)Insulin Resistance Index:Endurance exercise can significantly reduce the level of blood glucose level and insulin resistance index of high-fat diet rats and the GK rats;(3)High-fat diet has no significant effect on the expression of PGC-1α, ERRa and NRF-2 mRNA in the SD rats'muscle.(4)Endurance exercise significantly reduces the expression of PGC-1αmRNA in the high-fat diet SD rats and GK rats'skeletal muscle;(5)Endurance exercise significantly reduces the expression of ERRa and NRF-2 mRNA in the GK rats'skeletal muscle, while has no significant effect on the expression of ERRa and NRF-2 mRNA in the high-fat diet rats'skeletal muscleConclusion:(1)Endurance training can significantly control the body weight increase of the high-fat diet-rats(2)Endurance exercise can alleviate the too high-expressed-insulin resistance index, no matter it's caused by the high-fat diet or the congenital diabetes mellitus(3)Endurance exercise can reduce the expression of PGC-1α, ERRa and NRF-2 mRNA in the GK rat skeletal muscle, and reduce the expression of PGC-1αmRNA in the high-fat diet rats.We need to do further study to know the mechanism that the affect of endurance exercise on the mRNA expression of PGC-1α, ERRa and NRF-2.
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