Effect of ethanol on the changes in testicular protein expression in adult male rats

Ethanol consumption is a major cause of male infertility, but the exact mechanism is still largely unknown. This study attempted to investigate the effect of ethanol on sperm morphology, acrosome reaction status and the alteration of the testicular protein expressions. Fourteen male rats were divided into control and ethanol groups (n = 7/each group). Ethanol-treated rats received ethanol (5 g/kg, 40% v/v) via oral gavage for consecutive 14 days. Testosterone hormone, sperm parameters, and testicular and epididymal histopathologies were evaluated. In addition, the expressions of testicular proteins including androgen receptor (AR), heat shock protein 70 (HSP70), steroidogenic acute regulatory protein (StAR) and tyrosine-phosphorylated (TyrPho) proteins were investigated. The results showed that ethanol significantly increased percentage of abnormal sperm morphology and acrosome-reacted spermatozoa. Some seminiferous and ductus epididymal histopathologies were observed in ethanol-treated rats. Significantly, ethanol reduced serum testosterone and expressions of testicular AR and TyrPho proteins. However, the overexpression of StAR and HSP70 proteins in ethanol testis was found. It was concluded that the changes in testicular protein expressions may be involved in mechanism of male infertility caused from ethanol consumption.