State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
National key Lab of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, P.R. China.
J Pineal Res. 2016 May;60(4):435-47. doi: 10.1111/jpi.12327. Epub 2016 Apr 7.
Promotion of spermatogonial stem cell (SSC) differentiation into functional sperms under in vitro conditions is a great challenge for reproductive physiologists. In this study, we observed that melatonin (10(-7) M) supplementation significantly enhanced the cultured SSCs differentiation into haploid germ cells. This was confirmed by the expression of sperm special protein, acrosin. The rate of SSCs differentiation into sperm with melatonin supplementation was 11.85 ± 0.93% which was twofold higher than that in the control. The level of testosterone, the transcriptions of luteinizing hormone receptor (LHR), and the steroidogenic acute regulatory protein (StAR) were upregulated with melatonin treatment. At the early stage of SSCs culture, melatonin suppressed the level of cAMP, while at the later stage, it promoted cAMP production. The similar pattern was observed in testosterone content. Expressions for marker genes of meiosis anaphase, Dnmt3a, and Bcl-2 were upregulated by melatonin. In contrast, Bax expression was downregulated. Importantly, the in vitro-generated sperms were functional and they were capable to fertilize oocytes. These fertilized oocytes have successfully developed to the blastula stage.
在体外条件下促进精原干细胞（SSC）分化为功能性精子是生殖生理学家面临的巨大挑战。在这项研究中，我们观察到褪黑素（10(-7) M）补充可显著增强培养的 SSC 向单倍体生殖细胞的分化。这一点通过顶体蛋白酶的表达得到了证实。用褪黑素补充剂将 SSCs 分化为精子的比例为 11.85±0.93%，是对照组的两倍。褪黑素处理后，睾酮水平、促黄体生成素受体（LHR）转录本和类固醇急性调节蛋白（StAR）的转录水平上调。在 SSCs 培养的早期，褪黑素抑制 cAMP 水平，而在后期，它促进 cAMP 的产生。睾酮含量也观察到类似的模式。减数分裂后期的标记基因 Dnmt3a 和 Bcl-2 的表达被褪黑素上调。相反，Bax 的表达下调。重要的是，体外生成的精子是有功能的，能够使卵母细胞受精。这些受精的卵母细胞成功发育到囊胚阶段。
