Ameliorative effects of onion anthocyanin extract on spermatogenic function in cimetidine-induced testicular toxicity in male mice.

Cimetidine, an H2 receptor antagonist with anti-androgenic disrupts testicular structure and spermatogenesis. Anthocyanins in red onion (Allium cepa) have good antioxidant and cytoprotective action. This study compared the protective ability of onion-derived anthocyanin extract on the cimetidine-induced testicular toxicity in male mice, with respect to spermatogenic integrity, endocrine regulation, histopathology, and pharmacodynamic dose-response relationships. Sixty-four adult albino mice (male) were placed in control, anthocyanin (25-300 mg/kg), cimetidine (20 mg/kg), and cimetidine + anthocyanin (combinations) groups. Treatments were done in the form of intraperitoneally during 38 days. The assessment was done on testicular histology, seminiferous tubular diameter, germinal epithelium thickness, spermatogenic cell populations, Johnsen scores, daily sperm production, and Leydig cell indices. Anthocyanin co-treatment (25-300 mg/kg) produced a dose-dependent protective effect, with near-normal histological structure observed at 250-300 mg/kg. Daily sperm production increased significantly, showing a leftward shift in dose-response (ED50: 45.7 mg/kg vs. 57.9 mg/kg for anthocyanin alone). Onion anthocyanins exert potent, dose-dependent protective effects against cimetidine-induced testicular toxicity by preserving spermatogenesis and endocrine homeostasis, supporting their translational potential as fertility-protective adjuncts during gonadotoxic drug exposure.