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

Abstract

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.