Reproductive Injury in Male Rats from Acrylamide Toxicity and Potential Protection by Earthworm Methanolic Extract

This study examined the protective effect of earthworm extract (EE) on acrylamide (ACR)-induced reproductive dysfunction. Forty male rats were allocated into four groups (n = 10). The G I (control) group received distilled water (D.W.). The G II group received ACR (5 mg kg^-1 B.W. in D.W.) 5 days per week, orally, for 3 weeks. The G III group was administered EE (300 mg kg^-1 B.W in D.W.) 5 days per week, orally, for 3 weeks. The G IV group was pretreated with EE for 3 weeks and then co-treated with EE and ACR for an additional 3 weeks. ACR decreased the number of sperm, sperm viability, and total motility. However, it increased testosterone levels with no effect on the FSH or LH levels. Moreover, ACR increased the concentrations of malondialdehyde (MDA) and nitric oxide (NO). Meanwhile, it decreased the glutathione (GSH) concentration in testicular tissues. Notably, the expression levels of p53 and Ki-67 were increased in the degenerated spermatogenic cells and in the hyperplastic Leydig cells of the testis of the ACR-treated group, respectively. Acrylamide induced alterations in the testicular tissue architecture. Interestingly, EE restored the sperm parameters and recovered the testicular histological structures and the biochemical alterations induced by ACR. In conclusion, earthworm extract ameliorated ACR-induced reproductive toxicity via restoring the testicular antioxidant balance and suppressing p53 and Ki-67 expressions in testicular tissues.