Effects of ethanol consumption on chromatin condensation and DNA integrity of epididymal spermatozoa in rat

Alcohol abuse is considered as one of the problems associated with poor semen production and sperm quality. Both acute and chronic alcohol consumption may affect spermatozoal chromatin disorders through apoptosis. Therefore, for the first time, this experimental study was performed to evaluate the effect of ethanol consumption on sperm parameters and chromatin integrity of spermatozoa aspirated from cauda epididymis of rats. Twenty adult Wistar rats were divided into ethanol consumption and control groups. Access to ethanol and water was provided ad libitum for experimental and control animals, respectively. The cauda epididymal spermatozoa were aspirated for analysis of sperm parameters and sperm chromatin integrity with aniline blue (AB), chromomycin A3 (CMA3), toluidine blue (TB), and acridine orange (AO) assays. Sperm progressive and nonprogressive motility of ethanol-consuming rats were significantly decreased compared with control animals (P < .05). In addition, the rates of AB-reacted spermatozoa were similar in both groups (P > .05). However, with regard to CMA3, AO, and TB stainings, there was a significant increase in ethanol group when compared with the controls (P < .05). The majority of TB+ and AO+ spermatozoa were higher than “cut-off” value in ethanol group, whereas the mean rates of CMA3+ spermatozoa was below the “cut-off” value in both groups. The results showed that ethanol consumption disturbs sperm motility, nuclear maturity and DNA integrity of spermatozoa in rat. Therefore, ethanol abuse results in the production of spermatozoa with less condensed chromatin, and this may be one possible cause of infertility following ethanol consumption.