Effect of Aqueous and Ethanolic Extract of Mucuna Pruriens on Ovarian Histology in Letrozole-Induced Polycystic Ovarian Syndrome in Sprague-Dawley Rats: A Preliminary Study

Abstract

Polycystic ovarian syndrome (PCOS) is recognized as one of the most common endocrinopathy accounting for about one fifth of all infertility cases in women of reproductive age. The overall aim of this study is to determine the effect of Mucuna pruriens on letrozole-induced polycystic ovarian syndrome using an animal model. This study explores Mucuna pruriens as a possible therapeutic agent in the treatment and management of PCOS.
Forty female Sprague-Dawley rats averagely weighing 180 g were used for this study. They were divided into eight groups (N=5). Letrozole (1.0 mg/kg), administered for 21 days, was used to induce PCOS. Both ethanolic (100, 200 and 400 mg/kg body weight) and aqueous fractions (100, 200 and 400 mg/kg body weight) of Mucuna pruriens were administered for four weeks (100, 200 and 400 mg/kg body weight). Control animals received 3 mls of distilled water. Body weights were monitored weekly throughout the study. At the end of the experiment, animals were sacrificed; ovaries were excised, trimmed off fat, weighed and fixed in 10% formal saline for histological procedure.
Body weights increased significantly across all groups when post-administration weight was compared to pre-administration weight. The ovarian weights of the 400 mg/kg groups of both aqueous and ethanolic groups were comparable with control with the same value while those of low dose (200 mg/kg) and medium dose (100 mg/kg) were slightly lower than control, although they were not statistically significant. Histological sections of the Mucuna pruriens treated groups showed follicles at various stages of development when compared to the letrozole-induced group which exhibited numerous subcapsular cysts, with a thin granulosa layer and absent corpora lutea indicating anovulation.
The study showed that both aqueous and ethanolic fractions of Mucuna pruriens seed extract ameliorated the deleterious effect of polycystic ovarian syndrome on ovarian follicles by rescuing growing follicles from cystic formation.