目的:探讨锌稳态相关蛋白的表达,弱精子症(AS)患者精子中的G蛋白偶联受体39(GPR39)和ANO1mRNA,并分析其与精子活力的相关性。
方法:我们收集了82名PR+NP<40%的男性受试者的精液样本,PR<32%,精子浓度>15×10/ml(AS组,n=40)或PR+NP≥40%,PR≥32%,精子浓度>15×10/ml(正常对照组,n=42)。我们分析了常规精液参数,并使用计算机辅助精子分析系统测量了精浆中的锌含量,检测锌转运蛋白(ZIP13、ZIP8和ZNT10)的表达,金属硫蛋白(MT1G,MT1和MTF),通过实时定量PCR(RTqPCR),精子中的GPR39和钙依赖性氯通道蛋白(ANO1),通过激光共聚焦显微镜检查精子中的游离锌分布,免疫荧光染色检测精子中GPR39和MT1蛋白的表达,其次用Spearman秩相关分析其与精液参数的相关性。
结果:AS组与正常对照组精浆锌浓度差异无统计学意义(P>0.05)。与对照组相比,AS患者游离锌水平明显降低(P<0.05),MT1G的相对表达式,MTF,ZIP13,GPR39和ANO1mRNA(P<0.05),和AS组的GPR39蛋白(P<0.05)。两组间ZIP8、ZNT10和MT1mRNA的相对表达水平差异无统计学意义(P>0.05)。GPR39,ANO1,MT1G和MTFmRNA的相对表达水平与精子活力和进行性活动精子百分比呈正相关(P<0.05)。
结论:锌稳态蛋白(MT1G,MTF和ZIP13),GPR39和ANO1mRNA在弱精子症患者的精子中下调,与精子活力呈正相关。
OBJECTIVE: To explore the expressions of zinc homeostasis-related proteins, G protein-coupled receptor 39 (GPR39) and ANO1 mRNA in the sperm of patients with asthenozoospermia (AS), and analyze their correlation with sperm motility.
METHODS: We collected semen samples from 82 male subjects with PR+NP < 40%, PR < 32% and sperm concentration > 15×10⁶/ml (the AS group, n = 40) or PR+NP ≥ 40%, PR ≥ 32% and sperm concentration > 15×10⁶/ml (the normal control group, n = 42). We analyzed the routine semen parameters and measured the zinc content in the seminal plasma using the computer-assisted sperm analysis system, detected the expressions of zinc transporters (ZIP13, ZIP8 and ZNT10), metallothioneins (MT1G, MT1 and MTF), GPR39, and calcium-dependent chloride channel protein (ANO1) in the sperm by real-time quantitative PCR (RT qPCR), examined free zinc distribution in the sperm by laser confocal microscopy, and determined the expressions of GPR39 and MT1 proteins in the sperm by immunofluorescence staining, followed by Spearman rank correlation analysis of their correlation with semen parameters.
RESULTS: There was no statistically significant difference in the zinc concentration in the seminal plasma between the AS and normal control groups (P>0.05). Compared with the controls, the AS patients showed a significantly reduced free zinc level (P<0.05), relative expressions of MT1G, MTF, ZIP13, GPR39 and ANO1 mRNA (P<0.05), and that of the GPR39 protein in the AS group (P<0.05). No statistically significant differences were observed in the relative expression levels of ZIP8, ZNT10 and MT1 mRNA between the two groups (P>0.05). The relative expression levels of GPR39, ANO1, MT1G and MTF mRNA were positively correlated with sperm motility and the percentage of progressively motile sperm (P<0.05).
CONCLUSIONS: The expressions of zinc homeostasis proteins (MT1G, MTF and ZIP13), GPR39 and ANO1 mRNA are downregulated in the sperm of asthenozoospermia patients, and positively correlated with sperm motility.