Mechanistic insight into the protective effects of fisetin against arsenic-induced reproductive toxicity in male rats

Abstract

Arsenic is one of the most hazardous environmental contaminants, which adversely affects the dynamics of male reproductive system. Fisetin (FIS) is a bioactive flavonoid, which is known to exert strong antioxidative effects. Therefore, the current research was planned to evaluate the alleviative efficacy of FIS against arsenic-induced reproductive damages. Forty-eight male albino rats were divided into 4 groups (n = 12), which were treated as follows: (1) Control, (2) Arsenic-intoxicated group (8 mg kg^-1), (3) Arsenic + FIS-treated group (8 mg kg^-1 + 10 mg kg^-1), and (4) FIS-treated group (10 mgkg^-1). After 56 days of treatment, the biochemical, lipidemic, steroidogenic, hormonal, spermatological, apoptotic and histoarchitectural profiles of rats were analyzed. Arsenic intoxication reduced the enzymatic activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GSR), in addition to glutathione (GSH) level. Conversely, the levels of thiobarbituric acid reactive substance (TBARS) and reactive oxygen species (ROS) were increased. Moreover, it escalated the level of low-density lipoprotein (LDL), triglycerides and total cholesterol, while declining the level of high-density lipoprotein (HDL). Furthermore, steroidogenic enzymes expressions, 3β-hydroxysteroid dehydrogenase (HSD), 17β-HSD, steroidogenic acute regulatory protein (StAR), cholesterol side-chain cleavage enzyme (CYP11A1) and 17α-hydroxylase/17, 20-lyase (CYP17A1), were found to be reduced, which brought down the level of testosterone. Besides, the levels of gonadotropins (LH and FSH) were decreased. Additionally, a decline in sperm mitochondrial membrane potential (MMP), motility, epididymal sperm count and hypo-osmotic swelling (HOS) coil-tailed sperms was observed, whereas the dead sperms and structural damages (head, midpiece and tail) of sperms were escalated. Moreover, arsenic exposure up-regulated the mRNA expressions of apoptotic markers, namely Bax and caspase-3, whereas lowered the expression of anti-apoptotic marker, Bcl-2. In addition, it induced histoarchitectural changes in testes of rats. However, FIS treatment resulted in remarkable improvements in testicular and sperm parameters. Therefore, it was inferred that FIS could serve as a therapeutic candidate against arsenic-generated male reproductive toxicity attributing to its anti-oxidant, anti-lipoperoxidative, anti-apoptotic, and androgenic efficacy.