标题：Melatonin maintains mitochondrial membrane potential and decreases excessive intracellular Ca2+ levels in immature human oocytes
中文标题：褪黑素维持线粒体膜电位，降低未成熟人类卵母细胞内过量的钙水平
引用信息：Liu YJ, Ji DM, Liu ZB, Wang TJ, Xie FF, Zhang ZG, Wei ZL, Zhou P, Cao YX. Melatonin maintains mitochondrial membrane potential and decreases excessive intracellular Ca2+ levels in immature human oocytes. Life Sci. 2019 Oct 15;235:116810. doi: 10.1016/j.lfs.2019.116810. Epub 2019 Aug 28. PMID: 31472147.
摘要：
Aims:Previous reports have demonstrated that melatonin exists in multiple extrapineal sites, and higher amounts of melatonin are present in human follicular fluid than in serum, which indicates that it might play key roles in human oocyte maturation and subsequent embryonic development. Melatonin has been shown to be a potent antioxidant and might be beneficial to human oocytes during in vitro maturation (IVM). However, the underlying mechanisms of melatonin action during IVM have not been thoroughly investigated.
Main methods:Immunofluorescence staining, western blotting, and ELISA were applied to investigate whether melatoninergic components are expressed in the cultured human ovarian cumulus cells. TMRE staining and Fluo-4 AM staining were performed to detect the mitochondrial membrane potential and intracellular Ca2+levels of immature human oocytes respectively.
Key findings:First, cultured human ovary cumulus cells synthesized melatonin in vitro, and it expressed serotonin (the precursor of melatonin) and the two key enzymes, i.e. N-acetyltransferase (NAT) and hydroxyindole-O-methyltransferase (HIOMT). Additionally, the results suggest that melatonin maintains the mitochondrial membrane potential and decrease excessive Ca2+levels in immature human oocytes during IVM.
Significance:In conclusion, we provide evidence that the melatoninergic components were expressed in cultured human ovarian cumulus cells, and melatonin might reduce oxidative stress of human oocytes by ameliorating mitochondrial function. In view of the significant clinical value that immature human oocytes have in assisted reproductive technology (ART), our findings highlight a potential treatment strategy of using melatonin to improve mitochondrial function and to enhance the quality of human oocytes during IVM.
中文摘要：
目的: 以前的报道已经证明褪黑激素存在于多个会阴外部位，人类卵泡液中的褪黑激素含量高于血清，这表明褪黑激素可能在人类卵母细胞成熟和随后的胚胎发育中发挥关键作用。褪黑激素已被证明是一种有效的抗氧化剂，可能有益于人类卵母细胞体外成熟(IVM)。然而，褪黑激素在体外成熟过程中的作用机制尚未得到充分的研究。
主要方法: 采用免疫荧光染色法、西方墨点法染色法和酶联免疫吸附试验(ELISA)检测培养的人卵巢卵丘细胞中是否存在褪黑激素能成分。TMRE 染色和 Fluo-4 AM 染色分别检测未成熟卵母细胞的线粒体膜电位和细胞内 Ca2 + 水平。
主要发现: 首先，体外培养的人卵巢卵丘细胞合成褪黑激素，并表达5-羟色胺(褪黑激素的前体)和两种关键酶，即 N-乙酰基转移酶(NAT)和羟吲哚 -O- 甲基转移酶(HIOMT)。此外，研究结果表明，褪黑激素可以维持线粒体膜电位，减少体外受精期间未成熟人类卵母细胞中过量的钙离子水平。
意义: 总之，我们提供的证据表明，褪黑激素能成分在培养的人卵巢卵丘细胞中表达，褪黑激素可能通过改善线粒体功能减少人类卵母细胞的氧化应激。鉴于未成熟人类卵母细胞在辅助生殖技术(ART)中具有重要的临床价值，我们的研究结果强调了在 IVM 期间使用褪黑激素来改善线粒体功能和提高人类卵母细胞质量的潜在治疗策略。
原文链接：
https://www.sciencedirect.com/science/article/abs/pii/S0024320519307374?via%3Dihub
