[doi: 10.5505/2017ichc.PP-222]Effect of different aerobic exercise frequency on type 2 diabetes in ratNuray Alaca1, Serap Uslu2, Umit Ince3, Mustafa Serteser4, Guldal Suyen5, Hızır Kurtel62Istanbul Medeniyet University, Medical School, Department of Histology and Embriyology, Istanbul, Turkey 3Acibadem University, Medical School, Department of Pathology, Istanbul, Turkey 4Acibadem University, Medical School, Department of Biochemistry, Istanbul, Turkey 5Acibadem University, Medical School, Department of Physiology Istanbul, Turkey 6Marmara University, Medical School, Department of Physiology Istanbul, Turkey. OBJECTIVE: Recommendations for exercise and physical activity by professional organizations and government agencies advise that moderate-intensity physical activity may be accumulated in bouts of >10 min each to attain the daily goal of >30 min/day. Although accumulated approach is useful increasing adhesion of an individual to exercise program, benefits in diabetic conditions are not studied. Thus, the objectives of this study is to compare the alterations induced by long-moderate exercise pattern with short bouts of exercise for a given duration and volume on the histopathological structure of skeletal muscle in an experimental model of type 2 diabetes mellitus (T2DM). MATERIALS-METHODS: T2DM was induced by using nicotinamide (NAD-110mg/kg) and streptozotocin (STZ-65mg/kg) in Sprague Dawley rats (n:35) and diabetic rats were allocated into the groups of sedentary control (SC), sedentary diabetes (SD), diabetes and continuous exercise (DcE; swimming for 30 minutes/day and 5 days/week) and diabetes and short bout of exercise (DsbE, swimming, 3x10 minutes/day, 5 days/week). After 6 weeks of exercise, biochemical tests were performed to measure insulin and glucose. Histologic analyses consisting of modified gomori’s trichrome, hematoxylin-eosin stains, periodic Acid-Schiff and oil red o stains were performed. Additionally, muscle oxidative enzyme activities including cytochrome C oxidase (COX), succinate dehydrogenase (SDH) and Ragged Red Fibers (RRF) were analyzed. RESULTS: In the SD group, increased blood glucose were accompanied by interfibriller connective tissue accumulation (CTA) and vacuolization, increased RRF levels and atrophy (slow and fast twitch fibers). In addition, insulin levels and SDH positive fiber density were found to be decreased in SD group compared to SC (p<0,05). When compared to the SD group, significant improvements were observed in all training groups regardless of the exercise type. Blood glucose levels, CTA, vacuolization, muscle atrophy, content of muscle oxidative enzyme activities were all significantly improved in both DcE and DsbE groups compared to SD (p<0,05). CONCLUSION: The results of this study underlined the effect of exercise on myopathy and mitochondrial damage in the rat model of T2DM, while training frequency did not make any significant difference indicating the potential benefits of the accumulated approach. |