Protective role of selenium status on T₃/T₄ kinetics in rats under hyperlipidemia

Abstract

The effect of high fat diet (HFD) on thyroid hormones (T₃/T₄ ) and protective role of selenium (Se) were studied in rats. Se levels in serum and liver decreased significantly, whereas glutathione peroxidase (GSH-Px) in liver and lipid levels (cholesterol and triglycerides) in serum increased after 1, 2 and 3 months of HFD feeding in comparison to controls in all the three Se status i.e. deficient (0.02 ppm), adequate (0.2 ppm) and excess (1 ppm) groups. Levels of T₃/T₄ decreased significantly on HFD feeding, as compared to respective controls in all the groups. Within the deficient group, as Se deficiency progressed, T₃/T₄ levels decreased after 2 and 3 months in comparison to 1 month. A significant increase was observed in T₃/T₄ concentration on feeding 1 ppm (excess) Se supplemented diet, in comparison to adequate group. Also, in 1 ppm Se supplemented group as the Se deposition increased i.e. after 2 and 3 months, levels of T₃/T₄ increased significantly. So, the present study indicates that Se supplementation up to 1 ppm normalizes the T₃ and T₄concentrations or regulates the hypothyroidism induced by hyperlipidemia.