نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه فیزیولوژی ورزشی، دانشکده انسانی، واحد ساری، دانشگاه آزاد اسلامی، ساری
2 گروه فیزیولوژی ورزشی- دانشگاه آزاد اسلامی- واحد ساری
3 آزاد ساری
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and Purpose: Muscular atrophy is one of the most common complications of diabetes. Exercise training has been suggested as one of the treatment strategies for muscular atrophy in diabetes. Intermittent cycles of ischemia (ICI) protects tissues from subsequent ischemic injury. However, whether ICI has beneficial effects on diabetic atrophy remains unknown. The present study aimed to investigate the synergistic effect of ICI with resistance and endurance training on Murf-1 and Atrogin-1 gene expression and fiber diameter of the gastrocnemius muscle in diabetic rats.
Materials and Methods: In this experimental research, 42 wistar rats (age 8 weeks, weight 228.31±12.1 gr) were randomly divided into seven groups: normal control (C), diabetic (D), diabetic ischemic (I), diabetic resistance training (R), diabetic endurance training (E), diabetes ischemic +resistance training (IR), diabetes ischemic+ endurance training (IE). Diabetes was induced by one-step intraperitoneal injection of STZ (50 mg/kg). ICI was conducted by tightening a tourniquet (with a width of 8 mm) around the upper thighs 20 min before exercise and included three 5-minute cycles of ischemia, followed by five minutes of reperfusion. The training groups performed exercise training for six weeks and five days a week. Resistance training included climbing a ladder by attaching a weight to rats’ tails with 60% maximum voluntary carrying capacity (14 reperetion and 1 min rest between repetitions). Endurance training involves running on a animal treadmill. The speed for the first week is set at 9 meters per minute for 15 minutes. By the sixth week, the training speed is increased to 18 meters per minute for 30 minutes. Murf-1 and atrogin-1 gene expression was measured by RT-PCR and the diameter of fibers of gastrocnemius muscle through the staining with hematoxylin and eosin methods. Data were analyzed by two-way analysis of variance and Bonferroni post hoc tests.
Results: Murf-1 and Atrogin-1 gene expression significantly increased and fiber diameter of gastrocnemius muscle decreased in D group compared to C group (p=0.0001). Murf-1 and atrogin-1 gene expression decreased significantly in R (p=0.0001, p=0.0001), E (p=0.0001, p=0.0003), IR (p=0.0001, p=0.0001) and IE (p=0.0001, p=0.0001) compared to the C. Muscle fiber diameter increased significantly in R (p=0.034), E (p=0.007), IR (p=0.0003) and IE (p=0.0003) compared to the C.
Conclusion: It seems that aerobic and resistance exercise with intermittent cycles of ischemia are more effective in preventing muscular atrophy in diabetes than any of the exercise interventions alone. This is achieved by decreasing Murf-1 and Atrogin-1 gene expression and increasing muscle fiber diameter.
کلیدواژهها [English]
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