5-HEPE Ameliorates Aging of Duck Ovarian Granulosa Cells by Targeting FOXM1 and Suppressing Oxidative Stress

Oxylipins are tightly linked to ovarian function. However, the roles and mechanisms of oxylipins in ovarian aging of laying ducks remain poorly understood. In this study, 72-week-old laying Jinyun ducks were categorized into high-laying (HL) and low-laying (LL) groups. Plasma and ovarian tissues were analyzed for antioxidant indices, transcriptomic, and targeted lipidomic. Results demonstrated that, compared to the LL group, the HL group ducks exhibited lower levels of MDA in both plasma and ovarian tissues, while exhibiting higher levels of SOD, GSH-Px, and T-AOC. Differentially expressed genes were primarily enriched in fatty acid oxidation and inflammation-related pathways, with FOXM1 identified as a pivotal gene involved in delaying ovarian aging. Furthermore, oxylipin profiles in plasma and ovary exhibit marked distinctions between the HL and LL group ducks. Notably, 5-hydroxy-eicosapentaenoic acid (5-HEPE) was substantially upregulated in both plasma and ovaries of the HL group ducks. Meanwhile, 5-HEPE significantly enhanced FOXM1 expression and mitigated oxidative stress in granulosa cells. Collectively, this study provides the first comprehensive analysis of oxylipin changes in the ovaries and plasma of ducks with differing laying performances at the late-laying stage. These findings offer novel insights into the prevention and alleviation of ovarian oxidative stress in ducks during this period.