Resveratrol and dimethyl fumarate ameliorate testicular dysfunction caused by chronic unpredictable mild stress-induced depression in rats

Chronic stress is a major factor contributing to male infertility. Increasing evidence has demonstrated that resveratrol or dimethyl fumarate (DMF) has antioxidant and anti-inflammatory functions. Our study aimed to evaluate the protective effects of resveratrol or DMF against testicular dysfunction associated with chronic unpredictable mild stress (CUMS)-induced depression in rats. Rats were subjected to 8 weeks of CUMS to induce depressive-like symptoms. CUMS-induced depressive-like behaviours in rats were evidenced by increased serum corticosterone levels and decreased serum and hippocampal serotonin levels as well as decreased hippocampal BDNF levels. CUMS significantly reduced sucrose preference and increased immobility time in stressed rats. Furthermore, CUMS exposure resulted in a significant decrease in serum testosterone levels and testicular expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 side chain cleavage (CYP450scc) enzyme and C-kit. CUMS significantly decreased and increased testicular expression of beta-catenin and GSK-3 beta, respectively. CUMS also resulted in a significant increase in testicular expression of NF-kappa B, TNF-alpha, IL-I beta, and Bax and decreased Bcl-2 expression levels. CUMS increased testicular MDA levels and significantly decreased testicular GSH and serum total antioxidant capacity levels. The histopathological results provided evidence for the biochemical and molecular analyses. All of these effects were significantly ameliorated by the administration of resveratrol or DMF. In conclusion, our study reveals that resveratrol or DMF exert profound testicular protective effects in CUMS rats that are mediated in part by suppressing oxidative stress, inflammation, and apoptosis leading to the upregulation of serum testosterone levels, and testicular StAR, CYP450scc, c-kit and beta-catenin levels.