Characterization of Exercise-Induced Hyperketonemia in Streptozotocin-Diabetic Rats and the Effects on It of Prolonged Training

Abstract

Exercise-induced hyperketonemia was investigated using streptozotocin (STZ)-diabetic rats subjected to running exercise on a treadmill. The degrees of hyperketonemia after 50, 55 and 60% Vo_2max of exercises were similar in mild diabetic rats (fasting plasma glucose; FPG<11mM). The degree of hyperketonemia (especially an increase in acetoacetate; AcAc) after 60% VO_2max of exercise was correlated with FPG (P<0.01) and basal plasma ketone bodies (P<0.01). Prolonged training with 60% Vo_2max of exercise for 30 min 3 times per week for 6 wks reduced the increase in plasma ketone bodies induced by the exercise in both mild (FPG<11mM) and severe (FPG>22mM) diabetic rats. The exercise-induced increase in plasma glucagon in mild diabetic rats and free fatty acids (FFA) in severe diabetic rats are also reduced by the training. These results demonstrate that exercise-induced hyper-AcAc-emia correlated with the FPG level is reduced by prolonged training in diabetic rats, and might suggest that exercise-induced hyperketonemia is reduced by long-term exercise training also in diabetic patients.