维生素E和B12对冷冻精子活力和DNA的保护作用

摘要

Objective:To evaluate the effect of vitamin E and B12 supplementation in cryoprotectant on frozen sperm motility and DNA.Methods:Thirty two semen samples collected from normal men in our reproductive medicine center were divided into 3 groups according to add different vitamins in the cryoprotectant:no vitamin was added in the control group;5 mM Vit E was added in Vit E group;0.5％ Vit B12 was added in the Vit B12 group.The sperm motility,survival rate,acrosin activity and sperm DNA fragmentation rate(SDF) were compared among the three groups after sperm frozen-thawed.Results:The number of frozen-thawed sperm with motility of grade(a+b)and sperm survival rate in Vit E group were significantly higher than those in control group after preserved in liquid nitrogen for 72 hours(P＜0.01).However,there was no significant difference in acrosin activity among the three group (P＞0.05).The SDF rate was significantly decreased in Vit E group [(12.16+0.50)％] and Vit B12 group [(13.02+0.48)％] compared with the control group [(15.18±0.78)％](P＜0.01).Meanwhile,sperm average halo diameter in Vit E group [(6.76±0.14)μm] was significantly larger than that in the control group [(6.09+0.18)μm] (P＜0.01).There was no significant difference in sperm average halo diameter between the Vit B12 group and control group(P＞0.05).Conclusions:Supplementation of vitamin E and B12 in cryoprotectant can relieve sperm damage caused by freezing and thawing,and increase the frozen-thaw sperm motility,survival rate and sperm DNA integrity to a certain extent.%目的 探讨维生素E(Vit E)和Vit B12对冷冻精子活力和DNA的保护作用.方法 收集在我院生殖医学中心就诊的32例正常男性精液标本,按照添加维生素的不同分为3组:对照组:精液中只添加常规冷冻保护剂;Vit E组:添加常规冷冻保护剂和5 mM的VitE;Vit B12组:添加常规冷冻保护剂和0.5％的Vit B12.比较3组精子复苏后的精子活动力、存活率、顶体酶活性、精子DNA碎片率(SDF)等指标.结果 经液氮冷冻72 h复苏后,Vit E组活动力(a+b)级的精子数、精子存活率均显著高于对照组(P＜0.01);顶体酶活性在各组间比较无显著性差异(P＞0.05);Vit E组和Vit B12组的SDF[分别为(12.16±0.50)％、(13.02±0.48)％]均显著低于对照组的(15.18±0.78)％(P＜0.01);Vit E组的精子DNA平均晕轮直径[(6.76±0.14)μm]显著高于对照组[(6.09±0.18)μm](P＜0.01),Vit B12组与对照组比较无显著性差异(P＞0.05).结论 精子冷冻保护剂中添加适当浓度的Vit E可以缓解冻融过程对精子造成的伤害,在一定程度上提高冻融后精子活动力、存活率及精子DNA完整性.