Environmental pollutants exposure and male reproductive toxicity: The role of epigenetic modifications.

Male fertility rates have shown a progressive decrease in recent decades. There is a growing concern about the male reproductive dysfunction caused by environmental pollutants exposure, however the underlying molecular mechanisms are still not well understood. Epigenetic modifications play a key role in the biological responses to external stressors. Therefore, this review discusses the roles of epigenetic modifications in male reproductive toxicity induced by environmental pollutants, with a particular emphasis on DNA methylation, histone modifications and miRNAs. The available literature proposed that environmental pollutants can directly or cause oxidative stress and DNA damage to induce a variety of epigenetic changes, which lead to gene dysregulation, mitochondrial dysfunction and consequent male reproductive toxicity. However, future studies focusing on more kinds of epigenetic modifications and their crosstalk as well as epidemiological data are still required to fill in the current research gaps. In addition, the intrinsic links between pollutants-mediated epigenetic regulations and male reproduction-related physiological responses deserve to be further explored.