【摘要】 前列腺素F2α(prostaglandin F2α, PGF2α)在黄体溶解过程中具有关键作用，能够通过其受体介导黄体细胞的凋亡。然而，PGF2α对早期的黄体细胞并没有促凋亡的作用。铁死亡是近年来发现的由脂质过氧化驱动且依赖铁离子的程序性细胞死亡方式，但其在PGF2α介导的不同阶段黄体细胞凋亡中的作用仍不清楚。为了探究PGF2α对绵羊(Ovis aries)不同时期黄体组织铁含量、铁死亡及相关自噬基因表达的影响，探讨PGF2α引起早期黄体反应钝化、溶解中期和后期黄体的机制，本研究选取48只健康、体况良好且体重相近经同期发情处理的母羊，随机平均分为6组，分别为黄体早期实验组与对照组、黄体中期实验组与对照组、黄体后期实验组与对照组，实验组分别于发情周期第5天(黄体早期)、第9天(黄体中期)和第13天(黄体后期)注射1.5 mL PGF2α(0.15 mg)，对照组则在同一时间点注射等量的生理盐水，每次注射后3 h采集黄体组织，用于铁含量、铁死亡及自噬相关基因表达检测。结果表明，PGF2α可显著提高整个黄体期的铁含量(P<0.05)。在黄体早期，PGF2α显著上调抗铁死亡相关基因SLC7A11、NRF2、FTH1和促铁死亡基因ACSL4以及铁死亡相关蛋白Ferritin、GPX4、SLC7A11、LC3B、NCOA4的表达；显著下调抗铁死亡相关基因GPX4和伴侣蛋白介导自噬相关基因HSPA8的表达(P<0.05)。在黄体中期，PGF2α显著上调抗铁死亡相关基因SLC7A11和促铁死亡基因ACSL4的表达，显著上调铁蛋白自噬相关基因ATG5、脂噬相关基因TPD52，分子伴侣介导自噬相关基因HSPA5、HSPA8以及SLC7A11、LC3B蛋白的表达水平，显著下调促铁死亡相关基因NRF2的表达(P<0.05)，对GPX4、Ferritin、NCOA4蛋白表达水平无显著影响。在黄体后期，PGF2α显著上调了P53、ACSL4、GPX4、ATG5、HSPA5、HSPA8基因和GPX4、SLC7A11、LC3B蛋白的表达水平，显著下调了NRF2和FTH1基因和Ferritin蛋白的表达水平(P<0.05)，对NCOA4基因表达水平无显著影响。绵羊不同黄体期注射PGF2α后，其作用呈现显著的时序性差异，黄体早期：PGF2α上调SLC7A11、NRF2和FTH1，增强抗氧化防御，抑制ACSL4以隔离游离铁，抵抗铁死亡，维持黄体功能；黄体中期：PGF2α上调ACSL4形成促氧化环境，同时激活ATG5启动自噬，暂时延缓氧化损伤，但加剧脂质过氧化，为铁死亡奠定基础；黄体后期：PGF2α激活P53、抑制NRF2并进一步上调ACSL4，驱动脂质过氧化累积，铁蓄积加剧氧化应激，最终引发铁死亡，导致黄体退化。综上，PGF2α通过时序性调控铁死亡和自噬相关通路，驱动黄体从早期抗氧化防御到后期不可逆退化。本研究为黄体功能异常的干预提供了理论依据。更多还原

【Abstract】 Prostaglandin F2α(PGF2α) plays a critical role in luteolysis by mediating apoptosis of luteal cells through its receptor. However, PGF2α does not exhibit pro-apoptotic effects on early-stage corpus luteum(CL) cells. Ferroptosis, a recently discovered form of programmed cell death driven by lipid peroxidation and dependent on iron ions, remains unclear in its role during PGF2α-mediated apoptosis of luteal cells at different developmental stages. This study investigated the impacts of PGF2α on iron content, ferroptosis, and autophagy-related gene expression in ovine CL during early, mid, and late luteal phases. Forty-eight synchronized healthy ewes(Ovis aries) were randomly allocated into 6 groups(experimental vs. control for each phase). Experimental groups received 0.15 mg PGF2α on day 5(early), 9(mid), and 13(late luteal phase), while controls received saline at corresponding time points. CL tissues were collected 3 h postinjection for analyses. Results revealed that PGF2α significantly increased iron content throughout the luteal phase(P<0.05). Phase-specific responses were observed: Early-phase PGF2α upregulated anti-ferroptosis genes(SLC7A11, NRF2, FTH1), pro-ferroptosis gene ACSL4, and ferroptosis-related proteins(Ferritin, GPX4,SLC7A11, LC3B, NCOA4), while downregulating GPX4 and HSPA8(P<0.05). Mid-phase treatment enhanced SLC7A11, ACSL4, ATG5, TPD52, HSPA5, HSPA8, and corresponding proteins, but suppressed NRF2(P<0.05). Late-phase administration upregulated P53, ACSL4, GPX4, ATG5, HSPA5, HSPA8 genes and GPX4/SLC7A11/LC3B proteins, while downregulating NRF2, FTH1, and Ferritin(P<0.05). Mechanistic analysis revealed temporal regulation patterns: Early-phase PGF2α enhanced antioxidant defenses via SLC7A11/NRF2/FTH1 axis and iron sequestration to resist ferroptosis; mid-phase activated ACSL4-mediated pro-oxidative environment and ATG5-dependent autophagy, accelerating lipid peroxidation; late-phase triggered P53 activation, NRF2 suppression, and ACSL4 amplification, culminating in iron overload and irreversible ferroptosis-driven luteolysis. These findings demonstrate that PGF2α orchestrates sequential regulation of ferroptosis and autophagy pathways to drive CL transition from early antioxidant protection to terminal regression. This study provides theoretical basis for interventions in luteal dysfunction.更多还原