Mitochondria of Porcine Oocytes Synthesize Melatonin, Which Improves Their In Vitro Maturation and Embryonic Development

作者：Tianqi Zhu, Laiqing Yan, Shoulong Deng, Wenkui Ma, Fan Xia, Likai Wang, Xiao Ma, Guangdong Li, Zixia Shen, Yiwei Wang, Yao Fu, Pengyun Ji, Bingyuan Wang, Lu Zhang, Guoshi Liu · 发表于：Antioxidants · 年份：2024 · DOI：10.3390/antiox13070814 · 被引用次数：16 · 研究领域：Circadian rhythm and melatonin、Birth, Development, and Health、Genetics, Aging, and Longevity in Model Organisms

The in vitro maturation efficiency of porcine oocytes is relatively low, and this limits the production of in vitro porcine embryos. Since melatonin is involved in mammalian reproductive physiology, in this study, we have explored whether endogenously produced melatonin can help in porcine oocyte in vitro maturation. We have found, for the first time in the literature, that mitochondria are the major sites for melatonin biosynthesis in porcine oocytes. This mitochondrially originated melatonin reduces ROS production and increases the activity of the mitochondrial respiratory electron transport chain, mitochondrial biogenesis, mitochondrial membrane potential, and ATP production. Therefore, melatonin improves the quality of oocytes and their in vitro maturation. In contrast, the reduced melatonin level caused by siRNA to knockdown AANAT (siAANAT) is associated with the abnormal distribution of mitochondria, decreasing the ATP level of porcine oocytes and inhibiting their in vitro maturation. These abnormalities can be rescued by melatonin supplementation. In addition, we found that siAANAT switches the mitochondrial oxidative phosphorylation to glycolysis, a Warburg effect. This metabolic alteration can also be corrected by melatonin supplementation. All these activities of melatonin appear to be mediated by its membrane receptors since the non-selective melatonin receptor antagonist Luzindole can blunt the effects of melatonin. Taken together, the mitochondria of porcine oocy...