Impact of Alpha Tocopherol on the Liver Functions of Male Wistar Rats Exposed to Deltamethrin

Abstract

Aim: To evaluate the impact of alpha-tocopherol on liver function in Wistar rats exposed to deltamethrin. Study Design: A total of 40 male rats were randomly assigned to eight groups (n = 5). Group A = control; Group B = 25 mg/kg/bw/day of deltamethrin only; Group C = 12.5 mg/kg/bw/day of deltamethrin only; Group D = 6.25 mg/kg/bw/day of deltamethrin only; Group E = 0.1 mg/kg/bw/day of alpha-tocopherol only; Group F = 0.1 mg/kg/bw/day of alpha-tocopherol + 25 mg/kg/bw/day of deltamethrin; Group G = 0.1 mg/kg/bw/day of alpha-tocopherol + 12.5 mg/kg/bw/day of deltamethrin; and Group H = 0.1 mg/kg/bw/day of alpha-tocopherol + 6.25 mg/kg/bw/day of deltamethrin. Place and Duration of Study: The study was carried out in the animal house of the Department of Animal and Environmental Biology, Rivers State University, Port Harcourt (coordinates: 4°48′14″ N, 6°59′12″ E), between November 2025 and May 2026. Methodology: After a 35-day experimental period, blood samples were collected by ocular puncture, and serum was separated by centrifugation at 2500 g for 10 min for the determination of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) using their respective kits. For histopathological analysis, 0.5 g of the liver was fixed. Histological sections and photomicrographs were produced. Data were subjected to one-way ANOVA. Results: The results showed significant (p < 0.05) increases in ALT, AST, and ALP in Groups B, C, and D, which received deltamethrin only, compared with the other groups. Histopathological analysis showed that the liver epithelium of Groups A and E contained healthy, normal hepatocytes, whereas livers exposed to deltamethrin alone showed degenerated hepatocytes and multiple necrotic cells. Groups co-administered alpha-tocopherol showed many regenerating hepatocytes. Conclusion: Deltamethrin induced oxidative stress, while alpha-tocopherol provided antioxidant defence against liver injury in a dose-dependent manner, as evident in Groups F, G, and H.