Feng Shao-Yong, Zhang Li, Li Li, Wu Zheng-Hua, Cheng Jian-Jun, Ke Xin-Wen, Zhang Yan-Gang
Department of Urology, Shanxi Da Hospital / Shanxi Academy of Medical Sciences, Taiyuan, Shanxi 030031, China.
Department of Urology,Shanxi Da Hospital / Shanxi Academy of Medical Sciences, Taiyuan, Shanxi 030031, China.
Zhonghua Nan Ke Xue. 2017 Jan;23(1):49-56.
To study the correlation of the gene expressions of Chk1 and Chk2 with sperm concentration and motility.
According to sperm concentration and motility (percentage of progressively motile sperm), we divided 80 semen samples into four groups of equal number: normal control, oligozoospermia (OS), asthenospermia (AS), and oligoasthenozoospermia (OAS). We detected the sperm DNA fragmentation index (DFI) and viability and determined the expressions of Chk1 and Chk2 in the sperm by RT-PCR and Western blot.
Statistically significant differences were not found in sperm DFI among the control, OS, AS, and OAS groups (21.24±6.93, 19.67±7.64, 21.52±6.92, and 19.28±11.55, P>0.05), but observed in sperm concentration, progressive motility, and viability between the DFI >30% and DFI ≤30% groups (P<0.01). Compared with the normal control, sperm viability was remarkably decreased in the OS, AS, and OAS groups (［83.48±9.87］% vs ［63.86±9.16］%, ［50.45±16.99］%, and ［39.21±15.74］%, P<0.05). RT-PCR showed remarkable differences among the control, OS, AS, and OAS groups in the relative expression level of Chk1 mRNA (0.73±0.22, 0.62±0.14, 1.03±0.39, and 0.92±0.071, P<0.01), which was correlated positively with sperm concentration (b = 80.661, P<0.01) but negatively with sperm motility (b = －19.275, P < 0.01), as well as in that of Chk2 mRNA (0.66±0.30, 0.27±0.09, 0.59±0.19, and 0.42 ± 0.11, P<0.01), which was correlated negatively with sperm concentration (b = －90.809, P<0.01) but positively with sperm motility (b = 27.507, P <0.01). The relative expression levels of the Chk1 protein were significantly different among the four groups (0.63±0.05, 0.42±0.03, 1.13±0.08, and 0.87±0.07, P<0.01), which was correlated positively with sperm concentration (b = 55.74, P<0.01) but negatively with sperm motility (b =－22.649, P<0.01), and so were those of the Chk2 protein (1.23±0.36, 0.37±0.16, 0.87±0.08, and 0.68±0.12, P<0.01), which was correlated negatively with sperm concentration (b =－53.001, P<0.01) but positively with sperm motility (b = 16.676, P < 0.01).
Chk1 and Chk2 are significantly expressed in human sperm. In case of sperm DNA damage, up-regulated Chk1 expression may enhance sperm apoptosis and lead to asthenospermia, while increased Chk2 expression may inhibit spermatogenesis and result in oligospermia.
研究Chk1和Chk2基因表达与精子浓度及活力的相关性。
根据精子浓度和活力（前向运动精子百分比），将80份精液样本等分为四组：正常对照组、少精子症（OS）组、弱精子症（AS）组和少弱精子症（OAS）组。检测精子DNA碎片化指数（DFI）和活力，并通过RT-PCR和蛋白质免疫印迹法测定精子中Chk1和Chk2的表达。
对照组、OS组、AS组和OAS组的精子DFI差异无统计学意义（21.24±6.93、19.67±7.64、21.52±6.92和19.28±11.55，P>0.05），但DFI>30%组与DFI≤30%组的精子浓度、前向运动率和活力差异有统计学意义（P<0.01）。与正常对照组相比，OS组、AS组和OAS组的精子活力显著降低（［83.48±9.87］%对［63.86±9.16］%、［50.45±16.99］%和［39.21±15.74］%，P<0.05）。RT-PCR显示，对照组、OS组、AS组和OAS组的Chk1 mRNA相对表达水平差异有统计学意义（0.73±0.22、0.62±0.14、1.03±0.39和0.92±0.071，P<0.01），其与精子浓度呈正相关（b = 80.661，P<0.01），与精子活力呈负相关（b =－19.275，P<0.01）；Chk2 mRNA相对表达水平差异也有统计学意义（0.66±0.30、0.27±0.09、0.59±0.19和0.42±0.11，P<0.01），其与精子浓度呈负相关（b =－90.809，P<0.01），与精子活力呈正相关（b = 27.507，P<0.01）。Chk1蛋白的相对表达水平在四组间差异有统计学意义（0.63±0.05、0.42±0.03、1.13±0.08和0.87±0.07，P<0.01），其与精子浓度呈正相关（b = 55.74，P<0.01），与精子活力呈负相关（b =－22.649，P<0.01）；Chk2蛋白的相对表达水平差异同样有统计学意义（1.23±0.36、0.37±0.16、0.87±0.08和0.68±0.12，P<0.01），其与精子浓度呈负相关（b =－53.001，P<0.01），与精子活力呈正相关（b = 16.676，P<0.01）。
Chk1和Chk2在人类精子中显著表达。在精子DNA损伤时，Chk1表达上调可能增强精子凋亡并导致弱精子症，而Chk2表达增加可能抑制精子发生并导致少精子症。
