Exercise training improved insulin sensitivity and ovarian morphology in rats with polycystic ovary syndrome

Hyperandrogenism and hyperinsulinemia are major clinical features in women with polycystic ovary syndrome (PCOS). We hypothesized that serum insulin levels reduced by exercise could relieve hyperandrogenism and ameliorate polycystic ovarian morphology. Wistar female rats with 21-day-old were randomly divided into three groups: PCOS exercise (P-Ex), PCOS sedentary (P-Sed), and control sedentary (C-Sed). The rats with PCOS were induced by injection with testosterone propionate continuously. The exercise program was to swim with 120 min/d for two weeks. Fasting blood glucose (FBG) and insulin (FINS), estrogen (E (2)), progesterone (P), and testosterone (T) in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro Plus 6.0. The levels of FINS, E (2), and T in serum were significantly lower in P-Ex than in P-Sed. The ratios of FBG/FINS in P-Ex significantly increased in comparison with P-Sed. The levels of serum sex hormones in P-Ex were similar to C-Sed. There were no differences in blood glucose and serum progesterone among three groups. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles significantly decreased, and the numbers of antral follicles and corpora lutea significantly increased in P-Ex compared with P-Sed. The changes of ovarian morphology in P-Ex were similar to C-Sed. These results demonstrated that short-term exercise training can improve insulin sensibility, decrease serum androgen levels, and recover normal ovarian morphology. The exercise training is the basic therapeutic means for PCOS.