Citral Protects Human Endothelial Cells Against Hydrogen Peroxide-induced Oxidative Stress

Objectives: Oxidative stress plays a major role in endothelial dysfunction. Citral is a monoterpene aldehyde with antioxidant properties. This study aimed to investigate the effect of citral on human umbilical vein endothelial cells (HUVECs) under hydrogen peroxide (H2O2)-induced oxidative stress. Materials and Methods: The cells were treated with citral (0.625-10 mu g/mL) for 24 h before exposure to H2O2 (0.5 mM, 2 h). Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. The hydroperoxide concentrations and ferric reducing ability of plasma (FRAP) were measured in intra- and extracellular fluids. Results: Pretreatment of HUVECs with citral at concentrations of 5 and 10 mu g/mL significantly enhanced the cell viability in H2O2-induced cytotoxicity. It reduced intracellular hydroperoxide levels at the concentrations of 5 and 10 mu g/mL and extracellular hydroperoxide levels at the concentrations of 2.5-10 mu g/mL. Pretreatment with citral significantly increased the FRAP value in intra- and extracellular fluids at the concentration range of 1.25-10 mu g/mL. Conclusion: Antioxidant and cytoprotective effects were found for citral against oxidative damage induced by H2O2 in human endothelial cells. However, more studies in this area are needed to assess its clinical value for prevention and treatment of cardiovascular diseases.