Selenium requirement in children

Abstract

Under approved dietary treatment the daily Se intake amounted only to 1.0-4.7/ug in patients with phenylketonuria (PKU) or maple-syrup-urine disease (MSUD). For 120 days 5 patients got an oral Se supplementation by yeast rich in Se, daily dose 0.56 g yeast, equivalent to 45/ug Se. Before supplementation the Se contents of serum and whole blood were reduced to 5-16 ng/ml, 10-27 ng/ml resp., that means to 10-20% normal. The activity of the erythrocyte glutathione peroxidase (GSHPx) amounted only to 0.19-2.69 U37/g Hb. After 4-8 weeks of supplementation the Se contents of serum and whole blood reached normal values. The activity of the erythrocyte GSHPx showed only a slow increase of the values after 4-6 weeks of Se supplementation. Within 9-15 weeks it reached a plateau at low normal values - a time similar to normal red cell life span. There was a close positive relationship between the erythrocyte Se content and the activity of the erythrocyte GSHPx.- Although mammalian GSHPx has been shown to contain seleno-cysteine residues in polypeptide linkage, our knowledge about the Se requirements in man is still scarce.