Metabolism and biological activity of -tocopherol derived from vitamin E-enriched transgenic maize in broilers

BACKGROUND The aim of this study was to investigate the metabolism of alpha-tocopherol derived from vitamin E-enriched transgenic maize (VER) and its effects on antioxidant and immune functions in broilers aged 1-42 days. A total of 360 1-day-old male broilers were randomly divided into three groups containing six replicates with 20 broilers per replicate. The negative control (NC) group and the positive control (PC) group were given non-GM maize and non-GM maize plus exogenous vitamin E (VE), respectively, and the VER group was given VER, replacing the non-GM maize given to the NC group. Between days 1 and 21 and days 22 and 42, VE levels were 4.38 and 4.63 mg kg(-1) in the NC group, and 14.11 and 14.91 mg kg(-1) in the PC and VER group, respectively. RESULTS The results showed that alpha-tocopherol from both VER and additives increased alpha-tocopherol transfer protein and cytochrome P450 concentrations. Serum alpha-tocopherol and alpha-tocopherylquinone levels of broilers in the PC and VER groups were also significantly higher than those in the NC group (P < 0.05). Compared with the NC group, broilers in both groups that received alpha-tocopherol had reduced NF-kappa B p65 concentrations, significantly decreased serum prostaglandin E-2, interleukin-6, malondialdehyde, and hydrogen peroxide levels (P < 0.05), and significantly increased glutathione, glutathione peroxidase, and total antioxidant capacity (P < 0.05). CONCLUSION In summary, both VER and non-GM maize fortified with exogenous VE showed similar effects on broilers, indicating that the alpha-tocopherol in VER has sufficient biological activity. (c) 2020 Society of Chemical Industry