Aerobic training and diabetic nephropathy in the obese Zucker rat

The effects of aerobic exercise training on diabetes control and the development of renal microvascular disease were studied in the obese Zucker rat, an animal model of noninsulin dependent diabetes mellitus (NIDDM). Training consisted of 12 weeks of treadmill running, beginning at six weeks of age. Eight trained obese Zucker rats were compared to 15 obese sedentary controls and to 22 sedentary lean nondiseased littermates. Fasting blood glucose, percent of glycated hemoglobin, serum insulin, serum total cholesterol, body weight and kidney weight, creatinine clearance, urine total protein excretion, urine albumin excretion, and morphometric analyses of cortical glomeruli by light and electron microscopy were performed to evaluate metabolic control, renal function, and structure. Training was associated with less albuminuria, less mesangial volume expansion, and less glomerular basement membrane thickening compared to obese sedentary NIDDM animals. These results suggest that exercise training reduces the glomerular ultrastructural lesions and attenuates the albumin excretion rate in this rat model of obesity-related diabetes.