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

• Published in: International journal of molecular sciences 2016-06, Vol.17 (6), p.939-939
• Main Authors: He, Changjiu, Wang, Jing, Zhang, Zhenzhen, Yang, Minghui, Li, Yu, Tian, Xiuzhi, Ma, Teng, Tao, Jingli, Zhu, Kuanfeng, Song, Yukun, Ji, Pengyun, Liu, Guoshi
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphate - metabolism; Animal reproduction; Animals; antioxidant; Antioxidants; Biosynthesis; DNA, Mitochondrial - genetics; Female; Females; In Vitro Oocyte Maturation Techniques; Melatonin; Melatonin - metabolism; Membrane Potential, Mitochondrial; Mice; Mitochondria; Mitochondria - metabolism; oocyte; Oocytes - cytology; Oocytes - metabolism; Oogenesis; Reactive Oxygen Species - metabolism; Rodents; SNAT
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms17060939

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.