Selenium deficiency as a cause of overload of iron and unbalanced distribution of other minerals

Abstract

Previous studies have shown that there are hematological abnormalities in selenium (Se)-deficient animals. This study examined the effects of Se deficiency on various minerals in serum and other tissues of male Wistar rats. The animals were given free access to either Torula yeast-based Se-deficient (SeD) diet or Se-adequate (SeA) (containing 0.1 mg Se/kg diet as sodium selenite) diet. Blood was sampled after 12 and 24 weeks, and the rats were killed after 24 weeks, for the analysis of minerals in serum, liver, kidney, heart, and spleen. Analyses showed that Se deficiency affected the concentrations of magnesium, calcium, iron, copper, and zinc in selected tissues and serum. During the entire feeding period, serum iron concentration was 40-58% greater in SeD rats compared with SeA rats. The transferrin saturation with iron was significantly greater in SeD rats than in SeA rats (57-60% versus 30-31%). Iron concentrations in the tissues ranged from 1.1 to 2.5 times higher in SeD rats than in SeA rats (p < 0.05). Similarly but to a lesser extent, the concentrations of zinc and magnesium were significantly greater in the serum of SeD rats compared with SeA rats, and the concentrations of calcium was significantly higher in kidney and spleen and of copper in liver, while the concentration of magnesium was significantly lower in liver and kidney. These results suggest that Se deficiency may cause a secondary overload of iron and unbalanced distribution of other minerals.