Kumar Dharmendra, Agrawal Neeraj K
Department of Endocrinology and Metabolism, Institute of Medical Sciences, BHU, Varanasi, Uttar Pradesh, India.
Indian J Endocrinol Metab. 2024 May-Jun;28(3):308-314. doi: 10.4103/ijem.ijem_8_24. Epub 2024 Jun 26.
Altered DNA methylation pattern in sperms has been associated with infertility in males demonstrating defective spermatogenesis or low semen quality. Vitamin B-12, by affecting 1-carbon metabolism pathways, might alter the DNA methylation pattern. We aimed to study the correlation of serum vitamin B12 levels with aberrant DNA methylation in infertile male patients.
A cross-sectional study was conducted on 17 oligozoospermic infertile males (WHO criteria, 2010) and 10 healthy fertile males. Serum vitamin B12 levels were estimated using the chemiluminescence method. Global methylation was determined using the ELISA system (Imprint Methylated DNA Quantification Kit, Sigma-Aldrich). The levels of global DNA methylation were calculated and compared relative to the methylated (100%) control DNA provided with the kit.
Mean serum vitamin B12 concentration in the control group was higher than that of the case group. This difference in serum vitamin B12 concentration in both groups was found statistically significant. Although the results of this study show that oligozoospermic men have relatively lower global DNA methylation as compared to normozoospermic control, the values could not reach a statistically significant level. A small positive correlation was found between serum vitamin B12 levels and percent methylation defect (r = 0.14) but was statistically insignificant.
Our study concludes that oligozoospermic infertile males have a significant deficiency of vitamin B12 as compared to normozoospermic fertile males. This study did not find any significant difference in global DNA methylation between the two groups. The present study does not suggest any correlation between serum vitamin B12 level and percent DNA methylation.
精子中DNA甲基化模式的改变与男性不育有关，这些男性表现出精子发生缺陷或精液质量低下。维生素B-12通过影响一碳代谢途径，可能会改变DNA甲基化模式。我们旨在研究不育男性患者血清维生素B12水平与异常DNA甲基化之间的相关性。
对17名少精子症不育男性（符合2010年世界卫生组织标准）和10名健康有生育能力的男性进行了一项横断面研究。采用化学发光法测定血清维生素B12水平。使用ELISA系统（印迹甲基化DNA定量试剂盒，西格玛奥德里奇公司）测定整体甲基化。计算整体DNA甲基化水平，并与试剂盒提供的甲基化（100%）对照DNA进行比较。
对照组的平均血清维生素B12浓度高于病例组。两组血清维生素B12浓度的差异具有统计学意义。尽管本研究结果表明，与正常精子对照组相比，少精子症男性的整体DNA甲基化相对较低，但其值未达到统计学显著水平。血清维生素B12水平与甲基化缺陷百分比之间存在微弱的正相关（r = 0.14），但无统计学意义。
我们的研究得出结论，与正常精子有生育能力的男性相比，少精子症不育男性存在明显的维生素B12缺乏。本研究未发现两组之间在整体DNA甲基化方面有任何显著差异。本研究未表明血清维生素B12水平与DNA甲基化百分比之间存在任何相关性。
