Selenium levels in kidney, liver and heart of newborns and infants

Background: Among the tissues of humans the highest lever of selenium (Se) is found in the kidney and the lowest in the muscle. The Se level in tissues is age-dependent. Aim: To measure the Se level in kidney, liver and heart of newborns and infants who were horn in different periods of pregnancy and died of various diseases. Subjects: Tissues obtained from 49 infants deceased at I day to 2.5 months of age. Forty-five of them were premature infants born between 23 and 36 weeks of pregnancy, four were horn at term. Results: Se levels in kidney and heart (but not liver) increased gradually with the duration of pregnancy. Positive and significant correlations were found between the weeks of pregnancy and Se levels in kidney (r=0.433, P=0.023) and heart (r=0.313, P= 0.030). In the total group, the mean Se levels in the kidney (185 +/- 64.7 ng/g wet weight) and liver (177 +/- 59.8 ng/g) were two times higher than those in the heart (90.5 +/- 33.7 ng/g). In this study, the Se levels in kidney and liver were from 2.5 to 1.2 times lower than the values found in our previous study for healthy adult victims. In the heart, the Se levels were similar in infants and adults. No significant differences were found in the mean Se levels in the various tissues in infants who died due to respiratory distress syndrome, congenital heart disease, other diseases and the group as a whole. The low levels of Se in the tissues studied by us, as compared with data from other countries, are probably due to lower Se intake by pregnant women in Poland. Conclusions: This study demonstrates that Se level in kidney and heart, but not in liver, increases with the progress of pregnancy. The Se level in kidney and liver is two times higher compared with heart and significantly higher than in adult subjects. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.