Selenium-biofortified Gboma (Solanum macrocarpon L.) vegetable-supplemented diets increased circulating selenium levels and potentiated endogenous anti-inflammatory, antioxidant and immunomodulatory properties in Wistar rats

Abstract

Selenium biofortification of staple foods is a strategy for ameliorating Selenium deficiency among populations. The aim of this study is to investigate the effect of Selenium biofortification on some phytochemicals present in Gboma (Solanum macrocarpon L.) leaves and to assess the effect of its dietary inclusions on some antioxidant molecules, immunoglobulins and inflammatory cytokines in the serum of Wistar rats. Gboma, also called African Eggplant was cultivated on soil enriched with Selenium biofortified fertilizer and harvested at maturity. The phytochemicals present were assessed via HPLC. The samples were also included into the diet of Wistar rats (4% and 8% inclusions) for fourteen days. The serum was then collected and assayed for glutathione peroxidase (GPx), glutathione-S-transferase (GST) and catalase activities. Imuunoglobulins M, G, A and E as well as the inflammatory makers-tumor necrosis factor-α and interleukin-10 were also assayed for. The results showed that Selenium bioaccumulation increased the concentration of some phytochemicals such as chlorogenic acid, 4- hydroxybenzoic acid and delphinidin. An increase in the activity of the antioxidant enzymes was also observed in rats fed with Selenium biofortified Gboma leaves (4% and 8%), compared to control and rats fed diets supplemented with Gboma leaves without Selenium biofortification. In addition, IgG, IgM and IgA levels increased in the serum of treated rats, coupled with an increase in IL-10 levels. This study therefore, shows that Selenium biofortification enhanced the antioxidant and immunomodulatory properties of Gboma leaves.

Keywords: Antioxidants; Gboma; Immunoglobulins; Phytochemicals; Selenium biofortification.