褪黑激素通过调节 p38 信号通路改善铅诱导的线粒体稳态和卵巢损伤

Melatonin ameliorates Pb-induced mitochondrial homeostasis and ovarian damage through regulating the p38 signaling pathway

褪黑激素通过调节 p38 信号通路改善铅诱导的线粒体稳态和卵巢损伤

Authors: Zhuo-Nan Yang, Xin Du, An Wang, Yu-Hang Zhao, Yun-He Xia, Ling-Ge Shi, Si-Min Ding, Xin-Yu Yue, Fen Xing, Dong-Mei Ji, Dan Liang, Zheng-Bao Zha, Chun-Mei Liang, Yun-Xia Cao, Ya-Jing Liu

Source: Ecotoxicology And Environmental Safety

DOI: 10.1016/j.ecoenv.2025.117937

Abstract

Lead (Pb), a widespread metallic pollutant in the environment, has been found to have detrimental effects on the female reproduction system. Recently, our group discovered a significant correlation between toxic metals and reproductive endocrine diseases. However, there is limited research on the relationship between blood concentration of Pb and the risk of diminished ovarian reserve function (DOR). Melatonin (MT), as a unique antioxidant, has been shown to reduce Pb toxicity both in vivo and in vitro，but the role of MT on follicle development in Pb-exposed female C57BL6 mice, and the underlying mechanisms, have not been clearly identified. In this study, blood Pb level was detected in the DOR patients, and a significant elevation in Pb levels was observed compared to the control group. Subsequently, we investigated the impact of lead acetate trihydrate (0.2 %), an endocrine disruptor of heavy metals, on follicle development in mice. We observed abnormal follicle development induced by lead acetate trihydrate without concurrent follicular apoptosis or excessive autophagy. Furthermore, we found that co-treatment with MT (30 mg/kg) rescued Pb-induced abnormal follicle development. Anti-Müllerian hormone (AMH) is a commonly utilized marker to evaluate ovarian reserve function. Our observation revealed that MT treatment effectively reversed the decrease in AMH levels induced by Pb. Importantly, our results revealed that MT not only protected against the Pb-induced increase of nucleus-encoded proteins, including SDHA, mitofilin and MTCO2, but also rescued Pb-induced the increase of mitochondrial dynamic-related proteins, such as OPA1, MFN and FIS1. In addition, MT protected against the decrease of mitochondrial dynamic-related protein anti-mitochondrial fission factor (MFF) antibody expression and mitochondrial membrane potential level. Finally, MT rescued the Pb-induced inhibition of phosphorylation in the P38 signaling pathway. Conclusively, these findings provide compelling evidence that exposure to Pb influences mitochondrial homeostasis, and MT effectively restores the imbalance between mitochondrial fusion and fission, nucleus-encoded proteins, and improves ovarian reserve function through regulating P38 signaling pathway. These results indicate that targeting the P38 signaling pathway with MT could be a potential therapeutic strategy for treating DOR.

Keywords: Lead; Melatonin; Mitochondrial homeostasis; Ovarian reserve function; Signaling pathway.

摘要

铅（Pb）是一种广泛存在于环境中的金属污染物，已被发现对女性生殖系统有不利影响。最近，我们的研究小组发现有毒金属与生殖内分泌疾病之间存在显著的相关性。然而，关于血液中铅浓度与卵巢储备功能减退（DOR）风险之间关系的研究还很有限。褪黑素（Melatonin，MT）作为一种独特的抗氧化剂，已被证明在体内和体外都能降低铅的毒性，但MT对暴露于铅的雌性C57BL6小鼠卵泡发育的作用及其内在机制尚未明确。本研究检测了 DOR 患者血液中的铅含量，发现与对照组相比，DOR 患者血液中的铅含量明显升高。随后，我们研究了重金属内分泌干扰物三水醋酸铅（0.2 %）对小鼠卵泡发育的影响。我们观察到三水醋酸铅诱发了卵泡发育异常，但没有同时出现卵泡凋亡或过度自噬。此外，我们还发现，与 MT（30 毫克/千克）联合处理可缓解铅诱导的卵泡发育异常。抗缪勒氏管激素（AMH）是评估卵巢储备功能的常用指标。我们的观察结果表明，MT能有效逆转铅诱导的AMH水平下降。重要的是，我们的研究结果表明，MT不仅能防止铅诱导的细胞核编码蛋白（包括SDHA、mitofilin和MTCO2）的增加，还能挽救铅诱导的线粒体动态相关蛋白（如OPA1、MFN和FIS1）的增加。此外，MT 还能防止线粒体动态相关蛋白抗线粒体裂变因子（MFF）抗体表达和线粒体膜电位水平的下降。最后，MT 挽救了铅诱导的 P38 信号通路磷酸化抑制。总之，这些研究结果提供了令人信服的证据，表明暴露于铅影响线粒体平衡，而 MT 能有效恢复线粒体融合与裂变、核编码蛋白之间的失衡，并通过调节 P38 信号通路改善卵巢储备功能。这些结果表明，用MT靶向P38信号通路可能是治疗DOR的一种潜在治疗策略。

关键词：铅；褪黑素；线粒体平衡；卵巢储备功能；信号通路