Bitter Melon Seed Extract does not Alter Photoperiodic Effects on Reproduction of Male Golden Hamsters

Bitter melon (Momordica charantia, MC) has been used in traditional Korean medicine in treating diabetes. In addition, some reports were emerged, showing the antifertility activities of MC in mammals. We investigated the effects of ethanolic MC extract on the reproductive activity of golden hamsters whose spermatogenetic capacity is controlled by their photoperiods. The animals were divided into 4 groups: long photoperiod (LP) control, short photoperiod (SP) control, and LP animals treated with MC. The animals were orally ingested with low (0.03 g/kg) or high (0.15 g/kg) concentrations of the ethanolic extracts for 8 weeks on the daily basis. The control animals received the vehicle. The animals were then mated with age-matched females, experienced pregnancy. As results, the LP control animals showed active large testes but SP control animals displayed remarkably reduced testes. The animals treated with both concentrations of MC extracts demonstrated large testes, indicating fertile activity as animals in LP. LP control animals had litters as expected, but SP controls had no litters at all. MC extract showed the same results as LP animals in generating offsprings. These results suggest that the MC extract does not change the photoperiodic influence on reproductive activity of male golden hamsters.