Effects of selenium on selenoprotein synthesis and antioxidant parameters of bovine mammary epithelial cells

Abstract

This study aimed to investigate the effects of selenium (Se) on the selenoproteins synthesis and antioxidant parameters of bovine mammary epithelial cells (BMECs). The experiment was conducted as a single factor completely randomized design to explore the effect of different levels of Se supplementation (0, 10, 20, 50, and 100 nmol/l) on selenoproteins synthesis and antioxidant parameters of BMECs, and to screen the appropriate dose of Se supplementation ensuring a better antioxidant function. Se supplementation increased cell proliferation, the activities of glutathione peroxidase (GPx) and superoxide dismutase, total antioxidant capacity and seleoprotein P (SelP) content, and decreased reactive oxygen species and malondialdehyde levels in a dose-dependent manner. Se supplementation of 50–100 nmol/l had a better effect. Se supplementation also increased thioredoxin reductase (TrxR) activity in a dose-dependent manner, and Se supplementation of 20–50 nmol/l had a better promoting effect. The dose-dependent response between Se supplementation and mRNA and protein expression of GPx1 and TrxR1, as well as SelP mRNA expression was also observed in this experiment. The mRNA and protein expression of GPx1 was up-regulated with the addition of 50–100 nmol/l Se, and the mRNA expression of TrxR1 and SelP was up-regulated with the addition of 20–100 nmol/l Se. Results indicated that Se supplementation of 50 nmol/l had a better promoting effect on the selenoproteins synthesis and antioxidant parameters of BMECs.