Antioxidant activity of plicatin B on cultured human microvascular endothelial cells exposed to H2O2

Oxidative stress plays a crucial role in the pathogenesis of atherosclerosis by promoting endothelial dysfunction and impairing vascular relaxation. Flavonoids are largely investigated for their biological properties and particularly for their scavenging and antioxidant properties. In the current study, we evaluated the clastogenicity of the chalcone plicatin B in peripheral human lymphocytes (whole blood and pure lymphocytes) as well as its antioxidant activity and its ability to contrast dysfunction on human microvascular endothelial cells (HMEC-1) exposed to hydrogen peroxide. We measured in the cell culture medium the levels of 8-isoprostane, NOx, ET-1, and ICAM-1, as well as the expression of e-NOS, prepro-ET-1, and ICAM-1. In conclusion, our results demonstrate that the chalcone plicatin B (1-10 mu M) may represent a good candidate for the prevention of atherosclerosis, as it consistently reduces the oxidative/inflammatory process and is not genotoxic to human lymphocytes.