Cytoprotective and antioxidant effects of Echium amoenum anthocyanin-rich extract in human endothelial cells (HUVECs)

Abstract

Objective:<em> Echium amoenum </em>Fisch. & C.A. Mey. is used for the treatment of various diseases in traditional medicine. This plant is a major source of anthocyanins with beneficial cardiovascular properties such as anti-atherosclerotic and antihypertensive effects. In the present study, the protective and antioxidant effects of anthocyanin-rich <em>E. amoenum</em> extract were evaluated on human vascular endothelial cells (HUVECs) under oxidative stress. <br/>Materials and Methods: Cell viability and oxidative status were assessed on H₂O₂-induced oxidative stress (0.5 mM H₂O₂for 2 h) in HUVECs pretreated by anthocyanin-rich extract from the petals of <em>E. amoenum </em>(25-1000 µg/ml). Cytoprotective effect of the extract was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The hydroperoxides concentration and ferric reducing antioxidant power (FRAP) were assessed in intra- and extra-cellular fluid of pretreated cells. <br/>Results: Pretreatment of HUVECs with <em>E. amoenum</em> extract at the concentrations of 100-1000 µg/ml reduced the cell death resulted from the exposure to H₂O₂in a concentration-dependent manner. <em>E. amoenum</em> extract decreased hydroperoxides concentration and increased FRAP value in both intra- and extra-cellular fluid at different concentration ranges. Moreover, it did not show cytotoxic effects at the concentration range of 25-1000 µg/ml. <br/>Conclusion: These results suggest antioxidant and protective effect of anthocyanin-rich extract of the petals of <em>E. amoenum</em> against H₂O₂-induced oxidative stress in HUVECs. However, further investigations are needed for understanding the detailed mechanisms of cytoprotective effects of this traditional herbal medicine.