College of Biotechnology, U.P. Pandit Deendayal Upadhayaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go Anusandhan Sansthan (DUVASU), Mathura, Uttar Pradesh, 281001, India.
College of Veterinary Science and Animal Husbandry, U.P. Pandit Deendayal Upadhayaya Pashu Chikitsa Vigyan Vishwavidyalaya Evam Go Anusandhan Sansthan (DUVASU), Mathura, Uttar Pradesh, 281001, India.
Biol Trace Elem Res. 2020 Dec;198(2):478-492. doi: 10.1007/s12011-020-02077-z. Epub 2020 Feb 16.
Present study was undertaken on buck spermatozoa to investigate the effect of mercuric chloride on functional dynamics of buck spermatozoa. Four different concentrations (0.031, 0.125, 0.25 and 1.25 μg/mL) of mercuric chloride, which were 1/40, 1/10, 1/5 and equivalent to the LC value of HgCl, were selected for studying their effect following in vitro exposure for 15 min and 3 h. Exposure of spermatozoa to 0.031 μg/mL mercuric chloride for 3 h resulted in significant (p < 0.05) decrease in sperm motility, sperm having intact membrane, intact acrosome and high mitochondrial trans-membrane potential. However, following exposure to higher concentrations (0.25, 1.25 μg/mL), similar results were observed even after 15 min of exposure. HgCl significantly (p < 0.05) increased the levels of malondialdehyde and reactive oxygen species and significantly (p < 0.05) decreased total antioxidant capacity and superoxide dismutase activity in spermatozoa within 15 min of exposure. Mercuric chloride-treated spermatozoa did not show capacitation, rather exhibited spontaneous acrosome reaction along with significant increase in intracellular Ca and cAMP levels. Immuno-blotting of semen samples of control and 0.031 μg/mL mercury-treated groups showed low intensity bands of p55, p70, p80, p105 and p190 kDa tyrosine phosphorylation proteins while higher concentration-treated groups showed no such bands. Our findings evidently suggest that mercuric chloride even at 0.031 μg/mL adversely affected sperm functions, inhibited tyrosine phosphorylation proteins and capacitation due to oxidative stress. Spontaneous acrosome reaction (AR) in mercury-treated spermatozoa may possibly be due to increase in intracellular Ca and cAMP levels, and capacitation failure may be due to inhibition of tyrosine phosphorylation of proteins.
本研究旨在探讨氯化汞对雄鹿精子功能动力学的影响，选用了四种不同浓度（0.031、0.125、0.25 和 1.25μg/mL）的氯化汞，分别为 LC 值的 1/40、1/10、1/5 和 1/5，用于研究其在体外暴露 15 分钟和 3 小时后的作用。暴露于 0.031μg/mL 氯化汞 3 小时后，精子的运动能力显著降低（p<0.05），精子膜完整、顶体完整、线粒体跨膜电位高。然而，在暴露于较高浓度（0.25、1.25μg/mL）时，即使暴露 15 分钟，也观察到类似的结果。在暴露 15 分钟内，氯化汞显著增加了精子中丙二醛和活性氧的水平，并显著降低了总抗氧化能力和超氧化物歧化酶的活性（p<0.05）。暴露于氯化汞的精子未表现出获能，反而表现出自发性顶体反应，同时细胞内 Ca 和 cAMP 水平显著升高。对对照组和 0.031μg/mL 汞处理组的精液样本进行免疫印迹分析显示，低强度的 p55、p70、p80、p105 和 p190kDa 酪氨酸磷酸化蛋白带，而高浓度处理组则没有这些带。我们的研究结果明显表明，即使在 0.031μg/mL 的浓度下，氯化汞也会对精子功能产生不利影响，抑制酪氨酸磷酸化蛋白并因氧化应激导致获能失败。在汞处理的精子中发生自发性顶体反应（AR）可能是由于细胞内 Ca 和 cAMP 水平升高所致，而获能失败可能是由于抑制了蛋白质的酪氨酸磷酸化。
