Pathogenic Reactions of the Ovarian Surface Epithelium to Ovulation,Dimethylbenzanthracene,and Estrogen are Negated by Vitamin E

Abstract

Objective: Acute effects of ovulation, the tumor suppressor disruptor dimethylbenzanthracene, the mitogen estradiol-17β, and the antioxidant vitamin E on the ovarian epithelium were assessed in seasonally anestrous ewes. Methods: Dimethylbenzanthracene and vitamin E were administered before and estradiol after gonadotropin-induced ovulation. Ovaries were removed for histopathology one and three weeks following ovulation. Surface epithelial cells isolated at one week were immunostained for 8-oxoguanine and assayed for urokinase plasminogen activator secretion—markers of genotoxic and invasive potentials. Results: Ovarian surface invaginations and cortical inclusion cysts containing stratified epithelium were observed at three weeks in ovulated animals treated with dimethylbenzanthracene and estradiol. Progenitor cells were 8-oxoguanine positive and hypersecreted urokinase plasminogen activator. Untoward responses were circumvented by vitamin E. Conclusion: Antioxidant therapy appears to be of value in precluding periovulatory disturbances to the ovarian surface epithelium that has been associated with carcinogenesis.