CYP2E1 and obesity due to melanocortin 4 receptor deficiency: Moreover, spermatogenesis abnormalities and overexpression of CYP2E1 mRNA in male rats have also been correlated in experimental alcoholism, type I diabetes and obesity models [10,11], suggesting that a possible mechanism of these pathologies is the contribution to a high level of free radical production (ROS and RNS) and, consequently, an effect on spermatogenesis due to LPO and chromatin integrity.