Mitochondria Synthesize Melatonin to Ameliorate Its Function and Improve Mice Oocyte’s Quality under in Vitro Conditions

作者：Changjiu He, Jing Wang, Zhenzhen Zhang, Minghui Yang, Yu Li, Xiuzhi Tian, Teng Ma, Jingli Tao, Kuanfeng Zhu, Yukun Song, Pengyun Ji, Guoshi Liu · 发表于：International Journal of Molecular Sciences · 年份：2016 · DOI：10.3390/ijms17060939 · 被引用次数：230 · 研究领域：Circadian rhythm and melatonin、Reproductive Biology and Fertility、Genetics, Aging, and Longevity in Model Organisms

The physiology of oocyte in vitro maturation remains elusive. Generally, the oocytes have a very low maturation rate under in vitro conditions. In the current study, we found that melatonin promotes the maturation of oocytes in which mitochondria play a pivotal role. It was identified that; (1) mitochondria are the major sites for melatonin synthesis in oocytes and they synthesize large amounts of melatonin during their maturation; (2) melatonin improves mitochondrial function by increased mtDNA copy, mitochondrial membrane potential (ΔΨm) and mitochondrial distribution and ATP production in oocytes; (3) the meiotic spindle assembly is enhanced; (4) melatonin reduces ROS production and inhibits 8-oxodG formation, thereby protecting potential DNA mutation from oxidative damage. As a result, melatonin improves the quality of oocytes, significantly accelerates the developmental ability of IVF embryo. The results provide novel knowledge on the physiology of oocyte's maturation, especially under in vitro conditions.