Regulation of the ovarian oxidative status by leptin during the ovulatory process in XXXX .

@entity1976 @entity2310 @entity12609 @entity35 @entity4124
UNASSIGNED: Leptin exerts both stimulatory and inhibitory effects on the ovulatory process. In this study, we investigated whether these opposite effects involve changes in the oxidative status in response to different levels of leptin. To this end, we performed both in vivo and in vitro assays using ovaries of immature @entity35 primed with gonadotropins to induce ovulation. Superoxide dismutase (SOD) and catalase ( @entity12609 ) activity, lipid peroxidation, glutathione (GSH) content, and reactive oxygen species (ROS) were studied as oxidative damage-related parameters. The expression of @entity1976 , @entity2310 , and @entity4124 were measured by western blot as apoptosis-related biomarkers. The acute treatment with leptin, which inhibits ovulation, decreased SOD activity and increased active @entity4124 expression. No differences were found in @entity12609 activity, lipid peroxidation, or total GSH. In contrast, the daily administration of leptin, which induces ovulation, decreased GSH content, ROS levels, and @entity2310 and active @entity4124 expression, but caused no changes in other parameters. In addition, the daily administration of leptin induced follicular growth, measured by the number of antral follicles in ovarian sections. Using ovarian explant cultures, we found increased @entity1976 expression and decreased SOD activity at low and high concentrations of leptin respectively. Thus, leptin can modulate the oxidative status of the ovarian tissue, during the ovulatory process, by acting on different targets according to its circulating levels. At low concentration, leptin seems to play a protective role against the oxidative stress, whereas at high concentrations, this protein seems to be involved in cell death.
