Clinical Research and Translation Center, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, Fujian Province, China; Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou, Fujian Province, China.
Department of Epidemiology and Biostatistics, Ministry of Education Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.
Ecotoxicol Environ Saf. 2023 Feb;251:114532. doi: 10.1016/j.ecoenv.2023.114532. Epub 2023 Jan 12.
Selenium (Se) is essential for successful male reproduction. However, the association of Se status with human semen quality remains controversial and the underlying mechanisms are poorly understood. We measured seminal plasma Se concentrations, sperm mitochondrial DNA copy number (mtDNAcn), and sperm quality parameters among healthy Chinese men screened as potential sperm donors. Linear mixed-effects models were used to investigate the associations of within-subject pooled seminal plasma Se concentrations (n = 1159) with repeated sperm quality parameters (n = 5617); mediation analyses were applied to evaluate the mediating role of sperm mtDNAcn (n = 989). Seminal plasma Se concentrations were positively associated with sperm concentration and total count (both P for trend < 0.001). In adjusted models, men in the top vs. bottom quartiles of seminal plasma Se concentrations had 70.1 % (95 % CI: 53.3 %, 88.9 %) and 59.1 % (95 % CI: 40.5 %, 80.2 %) higher sperm concentration and total count, respectively. Meanwhile, we observed inverse associations between seminal plasma Se concentrations and sperm mtDNAcn, and between sperm mtDNAcn and sperm motility, concentration, and total count (all P for trend < 0.05). Mediation analyses suggested that sperm mtDNAcn mediated 19.7 % (95 % CI: 15.9 %, 25.3 %) and 23.1 % (95 % CI: 17.4 %, 33.4 %) of the associations between seminal plasma Se concentrations and sperm concentration and total count, respectively. Our findings suggest that Se is essential for male spermatogenesis, potentially by affecting sperm mtDNAcn.
硒（Se）对男性生殖功能至关重要。然而，硒状态与人类精液质量之间的关系仍存在争议，其潜在机制也知之甚少。我们测量了健康中国男性潜在捐精者的精浆硒浓度、精子线粒体 DNA 拷贝数（mtDNAcn）和精子质量参数。使用线性混合效应模型来研究个体内精浆硒浓度（n=1159）与重复精子质量参数（n=5617）之间的关联；应用中介分析来评估精子 mtDNAcn 的中介作用（n=989）。精浆硒浓度与精子浓度和总计数呈正相关（趋势 P 值均<0.001）。在调整后的模型中，处于精浆硒浓度最高四分位数和最低四分位数的男性精子浓度和总计数分别高出 70.1%（95%CI：53.3%，88.9%）和 59.1%（95%CI：40.5%，80.2%）。同时，我们观察到精浆硒浓度与精子 mtDNAcn 之间呈负相关，与精子活力、浓度和总计数之间也呈负相关（趋势 P 值均<0.05）。中介分析表明，精子 mtDNAcn 介导了精浆硒浓度与精子浓度和总计数之间分别为 19.7%（95%CI：15.9%，25.3%）和 23.1%（95%CI：17.4%，33.4%）的关联。我们的研究结果表明，硒对男性精子发生至关重要，其潜在机制可能是通过影响精子 mtDNAcn。
