Histo-protective efficacy of Withania somnifera (Ashwagandha) root extract against bisphenol A-induced testicular toxicity in rats

Abstract

Background: Bisphenol A (BPA) is a high-volume synthetic endocrine disruptor widely used in polycarbonate plastics and epoxy resins. Its prevalence in food containers, water bottles, and can linings leads to continuous dietary exposure, raising significant public health concerns. This drives scientific interest in finding effective, natural protective agents. Withania somnifera (Ashwagandha), a prominent adaptogen in Ayurvedic medicine, is renowned for its cytoprotective, antioxidant, anti-inflammatory, and stress-alleviating properties, suggesting potential protective benefits against chemical toxicants. Aim: This study was designed to evaluate the histo-protective efficacy of a standardized Withania somnifera (Ashwagandha) root extract (WSRE) against BPA-induced testicular histopathological damage in rats. Methods: Forty adult male Wistar rats were divided into four groups (n=10): Group I (Control) received the vehicle only; Group II (BPA) received 200 mg/kg body weight/day of BPA orally; Group III (Ashwagandha) received 500 mg/kg body weight/day of Ashwagandha orally and Group IV (BPA plus Ashwagandha) received the same doses of both BPA and Ashwagandha at the aforementioned doses. The treatment continued for 60 consecutive days. Following sacrifice, the testes were immediately dissected out, fixed in Bouin\'s solution, and processed through dehydration and paraffin embedding. Five µm thick sections were obtained and stained with Hematoxylin and Eosin (H & E) to evaluate criteria such as germ cell degeneration, disorganization, vacuolization, and sloughing of spermatogenic cells. Results: Histopathological analysis of the BPA-only group revealed severe testicular injury, including marked distortion of tubule architecture, significant thinning and disorganization of the germinal epithelium, extensive vacuolization, and sloughing of spermatogenic cells into the lumen. Spermatogenesis was severely disrupted, with a notable absence of mature spermatozoa in many tubules. In contrast, the BPA plus Ashwagandha co-treatment group exhibited dramatic histoarchitectural preservation. Seminiferous tubules appeared near normal, with well-organized germinal epithelial layers containing all stages of spermatogenic cells. Degeneration, vacuolization, and cellular sloughing were minimal compared to the BPA-only group. Conclusion: Withania somnifera (Ashwagandha) root extract exhibits significant protective effects against the histopathological damage caused by BPA in rat testes. By maintaining the structural integrity of the germinal epithelium and ensuring the complete spermatogenic cycle, it validates its potential as a protective phytotherapeutic intervention for male reproductive toxicity.