Gill Kamil, Jakubik Joanna, Kups Michal, Rosiak-Gill Aleksandra, Kurzawa Rafal, Kurpisz Maciej, Fraczek Monika, Piasecka Malgorzata
Department of Histology and Developmental Biology, Pomeranian Medical University in Szczecin, Żołnierska 48, 71-210 Szczecin, Poland.
Department of Urology and Oncological Urology, Regional Specialist Hospital in Szczecin, Arkońska 4, 71-455 Szczecin, Poland.
Folia Histochem Cytobiol. 2019;57(1):15-22. doi: 10.5603/FHC.a2019.0002. Epub 2019 Mar 14.
Contemporary professional jobs that often enforce a sedentary lifestyle and are frequently associated with testicular overheat, deserve special attention with respect to male fertility potential. Interestingly, the harmful effect of testicular heat stress on sperm characteristics including nuclear DNA integrity was well characterized; however, the influence of sedentary work on sperm chromatin has not yet been documented. Therefore, our research was designed to examine the potential effects of sedentary work not only on conventional semen features but also on sperm nuclear DNA status.
The study was carried out on ejaculated sperm cells obtained from men who spent ≥ 50% of their time at work (≥ 17.5 h per week) in a sedentary position (n = 152) and from men who spent < 50% of their time at work in a sedentary position (n = 102). Standard semen characteristics were assessed according to the WHO 2010 recommendations, while sperm nuclear DNA fragmentation (SDF) was evaluated using the Halosperm test.
There were no significant differences in the standard semen parameters between the study groups. The groups differed only in SDF parameter. The men who spent at least 50% of their work time in a sedentary position had a higher proportion of SDF than the men who spent < 50% of their time at work in a sedentary position (median value 21.00% vs. 16.50%, respectively). The incidence of low SDF levels (related to 0-15% sperm cells with abnormal DNA dispersion) was significantly lower (27.63% vs. 45.10%), the percentage of men with high SDF levels (related to > 30%) was significantly higher (30.92% vs. 16.67%) in group of men who spent at least 50% of their work time in a sedentary positon. Furthermore, these men were more than twice as likely to have not a low SDF level (OR: 0.4648) and had more than twice the risk of having a high SDF level (OR: 2.2381) than the men in less sedentary occupations.
Despite lack of association between sedentary work and conventional semen characteristics our study revealed detrimental effect of seated work on sperm nuclear DNA integrity. A sedentary job doubled the risk of high levels of sperm DNA damage. The pathomechanism could be related to testicular heat stress resulting in sperm chromatin remodelling failure during spermiogenesis. Therefore, it seems reasonable to simultaneously carry out routine seminological analyses and tests assessing sperm chromatin status while diagnosing male infertility.
当代一些职业常常使人久坐不动，且经常与睾丸过热相关，就男性生育潜力而言，值得特别关注。有趣的是，睾丸热应激对精子特征（包括核DNA完整性）的有害影响已得到充分描述；然而，久坐工作对精子染色质的影响尚未见报道。因此，我们的研究旨在探讨久坐工作不仅对传统精液特征，而且对精子核DNA状态的潜在影响。
本研究对从工作时≥50%的时间（每周≥17.5小时）处于久坐状态的男性（n = 152）和工作时<50%的时间处于久坐状态的男性（n = 102）获取的射精精子细胞进行。根据世界卫生组织2010年的建议评估标准精液特征，同时使用Halosperm试验评估精子核DNA碎片化（SDF）。
研究组之间的标准精液参数无显著差异。两组仅在SDF参数上有所不同。工作时至少50%的时间处于久坐状态的男性的SDF比例高于工作时<50%的时间处于久坐状态的男性（中位数分别为21.00%和16.50%）。在工作时至少50%的时间处于久坐状态的男性组中，低SDF水平（与0 - 15%的精子细胞DNA分散异常相关）的发生率显著较低（27.63%对45.10%），高SDF水平（与>30%相关）的男性百分比显著较高（30.92%对16.67%）。此外，与久坐程度较低职业的男性相比，这些男性的SDF水平不低的可能性高出两倍多（OR：0.4648），且SDF水平高的风险高出两倍多（OR：2.2381）。
尽管久坐工作与传统精液特征之间缺乏关联，但我们的研究揭示了久坐工作对精子核DNA完整性的有害影响。久坐工作使精子DNA高水平损伤的风险增加一倍。发病机制可能与睾丸热应激导致精子发生过程中精子染色质重塑失败有关。因此
