冷冻复苏对精子结构及表观遗传学影响

Effects of cryopreservation on sperm structure and epigenetics

精子的冷冻保存已广泛用于男性生育力保存和辅助生殖技术。然而,精子冷冻、保存与复苏过程可能造成结构和功能的损伤,包括精子活力、存活率、形态学及受精能力等方面的损伤;存在较大争议的是,精子冷冻复苏是否引起DNA完整性改变及表观遗传损伤。至今,有很多文章报道辅助生殖技术可能导致早期胚胎发育异常,甚至子代表观遗传缺陷,但是有关冷冻是否导致表观遗传缺陷的文章很少。本文系统介绍冷冻复苏对精子细胞膜、线粒体膜、DNA完整性的影响,重点介绍其对表观遗传学中DNA甲基化、组蛋白乙酰化和非编码RNA调控的影响,简要介绍了引起争论的原因和修复机制,并探索最佳冷冻方法及建立实验室规范与标准。

Human sperm cryopreservation has been widely applied in male fertility preservation and human assisted reproduction technologies （ARTs）.The ultralow temperature may lead to deleterious changes of sperm structure and function,including viability,motility,morphology and fertilization capacity.There are still controversies on whether cryopreservation affects sperm DNA integrity and the epigenetics.So far,a lot of reports concerned that ARTs might lead to abnormal early embryonic development and even offspring epigenetic defects,but a few papers were about whether the cryopreservation may lead to epigenetic defects.This paper systematically introduces the effect of frozenthawed spermatozoa on sperm membranes,mitochondrial membrane and DNA integrity,especially on the DNA methylation,histone acetylation and non-coding RNA regulation.The paper also briefly introduces the causes of the controversy and the repair mechanism after impair,and explores for the best method for cryopreservation and establishes the laboratorial standard.