Effects of exercise, diet, and their combination on metabolic-syndrome-related parameters in OLETF rats

This study was conducted to assess the effects of exercise, diet, and their combination on metabolic syndrome (MS) risk factors including visceral fat mass (VFM), glucose intolerance, and dyslipidemia in OLETF rats. Thirty-two male rats were assigned to exercise (OLETF-Ex), dietary treatment (-DT), combination (-Ex&DT), or sedentary (-Sed) groups. Daily voluntary exercise using a rotary wheel was performed in OLETF-Ex. Each treatment was conducted from 21 to 31 wk of age. An oral glucose tolerance test was performed before and after the treatment period. Absolute levels of VFM, subcutaneous fat mass (SFM), and serum lipids including triglyceride, total cholesterol, and LDL-cholesterol (LDL-C) were measured after the treatment period. All therapeutic treatments resulted in significantly lower levels of body weight, VFM, SFM, and serum lipids than in sedentary control rats. All therapeutic treatments were also found to improve indices of oral glucose tolerance. Of the 3 therapeutic treatments, serum LDL-C levels were significantly lower in OLETF-Ex and OLETF-Ex&DT than in OLETF-Sed. The data demonstrate that all therapeutic approaches tested were effective in improving a number of MS-related parameters in OLETF rats. However, exercise-based therapeutic intervention may provide additional benefits for improving fat metabolism in MS patients.