تازه های تحقیق
عنوان مقاله [English]
Background&Purpose: Physical inactivity is associated with dysregulation of intramuscular triglyceride (IMTG) metabolism leading to the accumulation of fatty acid metabolites and insulin resistance. The purpose of this study was to evaluate the effects of aerobic training and caloric restriction on intramuscular lipid metabolism, lipid profile and insulin resistance after 18 weeks high fat diet in male rat
Methodology: Study sample were consisted of forty eight Wistar male rats with average weight; 194.5±12.6 g. Blood and muscle samples were collected at, 18th and 28th weeks after an overnight fasting. After weight rats in first week, rats consume high-fat-diet. After 18 weeks High-fat-diet group randomly divided into control (C), calorie restriction (CR) and aerobic training (T) groups. Negative energy balance groups underwent an aerobic training (running) with intensity of 70 to 75% of VO2max, and %25 calorie restriction for 10 weeks. Adipose Triglyceride Lipase, Triacylglycerol (TAG) and diacylglycerol (DAG) Levels in soleus, insulin and glucose levels and lipid profile were measured. HOMA-IR was also calculated.
Results: The results of this study indicated that negative energy balance methods, decreased muscle DAG levels and serum concentrations of insulin, glucose, triacylglycerol and insulin resistance index in obese male rats (P≤0.05). Serum triacylglycerol and cholesterol levels decreased only in T group (P≤0.05).
Conclusion: This study indicated that negative energy balance methods can actually decrease TAG and DAG levels even with simultaneous consumption of high-fat-diet which is largely congruent with improvement in insulin resistance.
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