Carvacrol reduces abnormal and dead sperm counts by attenuating sodium arsenite-induced oxidative stress, inflammation, apoptosis, and autophagy in the testicular tissues of rats.

Arsenic (As) is a highly toxic metalloid. Carvacrol (CAR) is the active ingredient of Lamiaceae plants and has various biological and pharmacological properties. The present study investigated the protective effects of carvacrol (CAR) against testicular toxicity induced by sodium arsenite (SA). Rats were given SA (10 mg/kg) and/or CAR (25 or 50 mg/kg) for 14 days. Semen analyzes showed that CAR increased sperm motility and decreased the percentage of abnormal and dead sperm. It was determined that the oxidative stress induced by SA decreased with the increase of Nrf-2 and HO-1 expressions, SOD, CAT, GPx, and GSH levels, and MDA levels decreased after CAR treatment. It was observed that autophagy and inflammation triggered by SA in testicular tissue were alleviated by suppressing the expressions of LC3A, LC3B, MAPK-14, NF-κB, TNF-α, IL-1β, iNOS, and COX-2 biomarkers in rats given CAR. Also, CAR treatment suppressed SA-induced apoptosis by inhibiting Bax and Caspase-3 expressions in testicles and up-regulating Bcl-2 expression. Histopathological analyzes showed that rats given SA had deterioration in tubule structure and spermatogenesis cell line, especially a serious loss of spermatogonia cells, atrophy of seminiferous tubules, and deterioration of germinal epithelium. In the group given CAR, the germinal epithelium and connective tissue were in normal morphological structure and an increase in seminiferous tubule diameters was observed. As a result, it was determined that oxidative stress, inflammation, autophagy, and apoptosis induced by SA were suppressed by CAR, thus protecting the testicular tissue from damage and increasing semen quality.