Immunological role of zinc in preterm neonates.

Zinc (Zn), an essential trace element, plays a significant role in fetal development and biological defense during the embryonic and neonatal periods. Therefore, exploring the kinetics of Zn related to immune disturbances in preterm neonates is important. We here performed the measurement of Zn concentration along with immunological analysis of neonates and investigated the role of Zn in the neonatal period. Serum Zn concentrations were measured immediately after birth in neonates (329 cases). Moreover, for 25 cases, the kinetics of various immune cells and cytokines were measured by flow cytometry and electrochemiluminescence. We observed that Zn levels were inversely correlated with gestational weeks. Immune cell and cytokine analysis revealed an inverse correlation between HLA-DR on monocytes and Zn levels and between inflammatory cytokine interleukin-12 and Zn levels. Furthermore, oxidative stress status was inversely correlated with Zn levels. Our results suggested that the Zn dynamics immediately after birth, which show a negative correlation with the gestational week, can provide an anti-inflammatory and anti-oxidative environment for preterm neonates. The increased Zn concentration in the blood of preterm neonates may consequently protect neonates from perinatal stress.