泛素特异性蛋白酶7的表达与男性不育的相关性

Correlation between ubiquitin specific peptidase 7 expression and male infertility

目的探讨弱精子症(asthenozoospermia)和少弱精子症(oligoasthenozoospermia)患者精子中泛素特异性蛋白酶7(ubiquitin specific peptidase 7,USP7)的表达及其与男性不育的相关性。方法随机选取就诊于重庆医科大学附属第二医院妇产科生殖医学中心的不育症患者120例,根据2010年世界卫生组织标准进行精液参数常规分析,包括精子浓度和运动能力,分为弱精子症组(A组)37例、少弱精子症组(OA组)26例和正常精子(normozoospermia)组(N组)57例。采用免疫荧光染色和蛋白质印迹法检测USP7在人精子中的定位与表达变化,并进行相关性分析。结果 USP7定位于精子尾部中段和主段,与N组(1.63±0.76)相比,在A组(0.86±0.53)或OA组(0.62±0.43)精子中USP7蛋白的表达下降(P<0.01)。经相关分析,USP7蛋白水平与精子浓度(r=0.455 0,P=0.005 3)、前向运动精子百分率(r=0.431 2,P=0.008 7)和总活动率(r=0.443 8,P=0.006 7)呈正相关。结论 USP7表达下降与人精子活力和浓度降低有关,其可作为评估男性生育力的指标之一。

Objective To investigate the expression of ubiquitin specific peptidase 7 （USP7） in the sperm of infertile man suffering asthenozoospermia or oligoasthenozoospermia, and to explore its role in the pathogenesis of male infertility. Methods The semen samples were obtained from 120 donors attending the Fertility Clinic, the Centre of Reproductive Medicine, the Second Affiliated Hospital, Chongqing Medical University. The sperm specimens were divided into normozoospermia group （n=57）, asthenozoospermia group （n=37） or oligoasthenozoospermia group （n=26） after semen analysis according to 2010 WHO standards. The localization and expression of USP7 were examined using immunofluorescence and Western blotting analysis in the three groups. Then the correlation between USP7 expression and sperm parameters was analyzed. Results USP7 mainly localized in the middle part and main part of the sperm tail; the USP expression was significantly lower in asthenozoospermia group（0.86±0.53） and oligoasthenozoospermia group （0.62±0.43）compared with normozoospermia group （1.63±0.76, P〈0.01）. And USP7 expression was found positively correlated with the ratio of sperm moving forward（r=0.431 2, P=0.008 7）, total motility rate（r=0.443 8, P=0.006 7）, and sperm concentration（r=0.455 0, P=0.005 3）. Conclusion The lowered expression of USP7 is related to the reduction of human sperm motility and concentration, indicating that USP7 expression may serve as an indicator for sperm quality evaluation in infertile men.