The ameliorative effects of grape seed extract on bisphenol-A-induced reproductive toxicity and upregulated vitellogenin mRNA levels in Nile tilapia

Aquatic pollution has increased significantly in recent decades due to increased waste from various sources. Pollutants like bisphenol A (BPA) are endocrine disruptors that interfere with natural hormones, impacting development, fertility, and homeostasis. This study assessed the impact of BPA on the freshwater fish Oreochromis niloticus, focusing on genotoxicity, reproductive toxicity, and endocrine disruption. It also explored the protective effects of dietary grape seed extract (GREX^®) against BPA toxicity. One hundred eighty mixed-sex fish, averaging 15.04 ± 0.13 g, were randomly divided into four groups (three replicates each). The first group served as the control (0 mg GREX^®/kg), the second group received 200 mg GREX^®/kg, the third group was exposed to 3 mg BPA/L in water, and the fourth group received 3 mg BPA/L and 200 mg GREX^®/kg. Treatments lasted for 60 days. Body weight, gonadosomatic index (GSI), hepatosomatic index (HSI), cholesterol, triglycerides (TG), estradiol (E2), testosterone (T), cortisol, gonadal malondialdehyde (MDA), and superoxide dismutase (SOD) were measured. A histopathological examination of the liver, testes, and ovaries was conducted. BPA exposure induced significant pathophysiological alterations, including a significant decrease in GSI, HSI, E2, T, and gonadal antioxidant enzymes, while increasing cortisol, cholesterol, triglycerides (TG), and gonadal MDA. It also resulted in detrimental gonadal histology and downregulation of vitellogenin (VTG) mRNA levels. However, GREX^® significantly improved these BPA-induced effects and restored the VTG mRNA levels. GREX^® likely ameliorates BPA reproductive toxicity via antioxidant and stress-relieving mechanisms that improve gonadal sex hormones and pathology.