Zinc Ions Induce Inflammatory Responses in Vascular Endothelial Cells

Using one particulate zinc oxide (ZnO) and two soluble zinc compounds (Zn(NO(3))(2) and Zn(CH(3)COO)(2)), we aimed to clarify if zinc ions (Zn(2+)), like particulate ZnO, caused inflammatory responses in vascular endothelial cells. Treatments of human umbilical vein endothelial cells (HUVECs) with 368.6 mu M of each zinc compound caused marked increases in I kappa B alpha phosphorylation and intercellular adhesion molecule-1 (ICAM-1) expression. Treatments with Zn(CH(3)COO)(2) (50-350 mu M) induced a dose-dependent ICAM-1 expression. These results show that Zn(2+) alone is sufficient to induce similar levels of ICAM-1 expression as ZnO particles, suggesting that dissolved Zn(2+) may play the major role in inflammatory effect of ZnO particles on vascular endothelial cells.