细胞外信号调节激酶和p38丝裂原活化蛋白激酶的表达水平对人精子活动力的影响

目的:比较细胞外信号调节激酶(ERK)、P38丝裂原活化蛋白激酶(P38MAPK)的磷酸化和蛋白表达水平在正常精子和弱精子症患者精子中的差异,旨在探讨ERK和P38MAPK表达水平与精子活动力的相关性。方法:收集正常精液(精子浓度≥20×106/ml,a级精子≥25%或a+b级精子≥50%)和弱精子症患者精液(精子浓度≥20×106/ml,a级精子<25%或a+b级精子≤40%)各20份,洗涤后提取精子总蛋白,采用Western印迹方法分别检测ERK、P38MAPK的磷酸化和蛋白表达水平。结果:ERK和P38MAPK在正常精子和弱精子症患者精子中均有表达,ERK、P38MAPK蛋白表达水平和P38MAPK磷酸化水平在弱精子症患者组显著升高(P<0.05),而两组间ERK磷酸化水平差异无统计学意义(P>0.05)。结论:人精子ERK、P38MAPK蛋白表达水平和P38MAPK磷酸化水平升高可能是精子活动力低下的原因之一。

ERK and P38MAPK expressions and human sperm motility

Objective： To compare the phosphorylation and protein expression of extracellular-signal regulated protein kinase（ERK） and P38 mitogen activated protein kinase（P38 MAPK） in the ejaculated spermatozoa of healthy volunteers and asthenospermia males,and to explore the correlation of ERK and P38 MAPK with human sperm motility.Methods： Semen samples were collected from 20 healthy volunteers（sperm concentration ≥20 × 106 /ml,grade a sperm ≥25% or grade a ＋ b sperm ≥50%） and 20 infertile males with asthenospermia（sperm concentration ≥20 × 106/ml,grade a sperm 25% and grade a ＋ b sperm ≤40%） and classified as a control and an asthenospermia group.Total protein in spermatozoa was extracted from all the subjects,and Western blotting was used to detect phosphorylation and protein expression levels of ERK and P38 MAPK.Results： Compared with the control group,the protein expression levels of ERK and P38 MAPK and the phosphorylation level of P38 MAPK were significantly increased in the asthenospermia group（P0.05）,but there were no statistically significant differences in the phosphorylation level of ERK between the two groups（P0.05）.Conclusion： The up-regulated protein expressions of ERK and P38MAPK and increased phosphorylation level of P38 MAPK in human sperm may be involved in the pathogenesis of asthenospermia.