Protective effects of peoniflorin against hydrogen peroxide-induced oxidative stress in human umbilical vein endothelial cells

Peoniflorin (PF), extracted from the root of Paeonia lactiflora Pall., has been reported to have anti-inflammation and antioxidant effects in several animal models. Herein, we investigated the protective effects of PF against hydrogen peroxide (H2O2)-induced oxidative damage in human umbilical vein endothelial cells (HUVECs). HUVECs were treated by H2O2 (240 mu mol/L) with or without PF. PF significantly increased the percent cell viability of HUVECs injured by H2O2 using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. By flow cytometric analysis, PF markedly attenuated H2O2-induced apoptosis and intracellular reactive oxygen species production. In addition, PF also displayed a dose-dependent reduction of lactate dehydrogenase leakage, malondialdehyde formation, and caspase-3 proteolytic activities in H2O2-treated cells, which was accompanied with a restoration of the activities of endogenous antioxidants, including total superoxide dismutase and glutathione peroxidase. Finally, Western blot data revealed that H2O2 upregulated phosphorylation of extracellular signal-regulated kinase 1/2 in HUVECs, which was almost completely reversed by PF. Taken together, our data provide the first evidence that PF has a protective ability against oxidative damage in HUVECs. PF may be a candidate medicine for the treatment of vascular diseases associated with oxidative stress.