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, No. 13 Hangkong Rd, Wuhan 430030, Hubei Province, China.
Department of Epidemiology and Biostatistics, School of Public Health, Zhengzhou University, Zhengzhou, Henan Province, China.
Environ Int. 2021 Oct;155:106586. doi: 10.1016/j.envint.2021.106586. Epub 2021 Apr 25.
Essential elements such as iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), selenium (Se), rubidium (Rb), strontium (Sr), and molybdenum (Mo) are necessary for reproductive health. However, their associations with human semen quality remain inconclusive.
To investigate the associations of urinary Fe, Co, Cu, Zn, Se, Rb, Sr, and Mo concentrations with semen quality in healthy men screened as potential sperm donors and identify critical windows of susceptibility.
1428 healthy men provided 3766 urine and 6527 semen samples, which were measured for urinary essential element concentrations and sperm quality parameters, respectively. Linear mixed models and cubic spline curves were used to evaluate associations between urinary essential elements and semen quality. Multiple informant models were used to identify potential critical windows of susceptibility.
Linear mixed models and cubic spline curves showed positive dose-response relationships between urinary Zn and sperm concentration and total count and between urinary Mo and total sperm count [all False Discovery Rate (FDR) adjusted p-value for trend < 0.05]. In the multiple-element linear mixed models, the men in the highest versus lowest quartiles of urinary Zn and Mo had a higher sperm concentration of 17.5% (95% CI: 2.8%, 34.2%; p-value for trend = 0.006) and total sperm count of 18.3% (95% CI: 1.4%, 38.0%; p-value for trend = 0.027), respectively. Urinary Zn was also positively associated with total sperm count in a dose-dependent manner (p-value for trend = 0.036), though the percentile difference in total sperm count between men in the highest and lowest quartile was not statistically significant (16.4%, 95% CI: -1.7%, 37.9%). These associations appeared to be stronger when urinary Zn and Mo were measured at 0-9 days before the date of semen examination (i.e., corresponding to epididymal storage).
Higher urinary Zn and Mo, particularly during the period of epididymal storage, were associated with greater sperm production.
铁（Fe）、钴（Co）、铜（Cu）、锌（Zn）、硒（Se）、铷（Rb）、锶（Sr）和钼（Mo）等必需元素对生殖健康至关重要。然而，它们与人类精液质量的关系尚不确定。
调查健康男性潜在精子供体的尿液中 Fe、Co、Cu、Zn、Se、Rb、Sr 和 Mo 浓度与精液质量的关系，并确定易感的关键窗口期。
1428 名健康男性提供了 3766 份尿液和 6527 份精液样本，分别用于测量尿液中必需元素浓度和精子质量参数。线性混合模型和三次样条曲线用于评估尿液中必需元素与精液质量之间的关系。多信息模型用于确定潜在的易感关键窗口期。
线性混合模型和三次样条曲线显示，尿液 Zn 与精子浓度和总计数之间以及尿液 Mo 与总精子计数之间呈正剂量反应关系（所有经 False Discovery Rate（FDR）校正的趋势检验 p 值均<0.05）。在多元素线性混合模型中，与尿液 Zn 和 Mo 最低四分位数相比，最高四分位数的男性精子浓度高 17.5%（95%置信区间：2.8%，34.2%；趋势检验 p 值=0.006），总精子计数高 18.3%（95%置信区间：1.4%，38.0%；趋势检验 p 值=0.027）。尿液 Zn 与总精子计数呈剂量依赖性正相关（趋势检验 p 值=0.036），尽管最高四分位数与最低四分位数之间的总精子计数差异无统计学意义（16.4%，95%置信区间：-1.7%，37.9%）。当尿液 Zn 和 Mo 是在精液检查日期前 0-9 天（即对应于附睾储存期）测量时，这些关联似乎更强。
尿液 Zn 和 Mo 浓度较高，尤其是在附睾储存期间，与精子生成量增加有关。
