双酚A暴露对哺乳动物精子蛋白酪氨酸磷酸化的影响

Effects of bisphenol A exposure on proteins tyrosine phosphorylation in mammalian sperm

双酚A(BPA)是一种人工合成的雌激素性化合物,广泛存在于环境中,对哺乳动物内分泌有干扰作用,影响雄性生殖系统功能。本研究以新鲜猪精子、17℃保存猪精子以及小鼠精子为对象,采用体外培养方法,利用蛋白免疫印迹(WB)和免疫荧光技术,分析不同浓度BPA(0、0.1、1、10、100μmol·L^(-1))暴露对哺乳动物精子蛋白酪氨酸磷酸化的影响及分子机制。结果表明:低中浓度(0.1、1μmol·L^(-1))BPA暴露对新鲜猪获能精子蛋白酪氨酸磷酸化具有显著促进作用,但在高浓度(10、100μmol·L^(-1))BPA暴露下,猪获能精子蛋白酪氨酸磷酸化呈现降低趋势。BPA暴露下,小鼠获能精子蛋白酪氨酸磷酸化随BPA浓度的增加而增强,并且BPA影响猪和小鼠精子获能相关酪氨酸磷酸化修饰的蛋白种类不同。表明BPA暴露对哺乳动物精子的影响具有物种特异性。免疫荧光结果显示BPA对精子蛋白酪氨酸磷酸化的影响主要发生在鞭毛的中段和主段。

Bisphenol A(BPA) is a synthetic estrogen compound, which widely exists in the environment, interferes with mammalian endocrine and affects the function of reproductive system of males. Taking fresh sperm of boar, 17 ℃ preservation boar sperm, and mouse sperm as test materials, we examined the effects of BPA(0, 0.1,1,10,100 μmol·L^(-1)) on proteins tyrosine phosphorylation in sperm and the molecular mechanism by using wes-tern blot(WB) and immunofluorescence techniques coupled to in vitro culture method. The results showed that low BPA concentration(0.1, 1 μmol·L^(-1)) markedly accelerated the protein tyrosine phosphorylation of fresh boar capacitated sperm. However, the tyrosine phosphorylation of boar sperm decreased in high BPA concentration(10, 100 μmol·L^(-1)). The tyrosine phosphorylation of the mouse sperm raised with the increases of BPA concentration. Moreover, BPA affected different kinds of proteins related to tyrosine phosphorylation modification of porcine and mouse sperm capacitation, suggesting that the effect of BPA exposure on mammalian sperm was species-specific. Furthermore, the results of immunofluorescence showed that the effects of BPA on protein tyrosine phosphorylation in sperm mainly occurred in the middle and principal piece of flagellum.