Cytoprotective and antioxidant effects of human lactoferrin against H(2)O(2)-induced oxidative stress in human umbilical vein endothelial cells

BACKGROUND: Lactoferrin (LF) is an iron-binding glycoprotein with antioxidant, anti-inflammatory and nitric oxide-dependent vasodilatory properties. In the present study, we investigated the protective and antioxidant effects of LF on H(2)O(2)-induced oxidative stress in human umbilical vein endothelial cells (HUVECs). MATERIALS AND METHODS: HUVECs were pretreated by (6.25–100 μg/ml) LF for 24 h and then exposed to 0.5 mM H(2)O(2) for 2 h. Cell viability was assessed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The intra- and extra-cellular hydroperoxides concentration and ferric reducing antioxidant power (FRAP) were determined in pretreated cells. RESULTS: Pretreatment of HUVECs with LF at the concentrations of 25–100 μg/ml significantly reduced the cytotoxicity of H(2)O(2) in a concentration-dependent manner using MTT assay. LF pretreatment at different concentration ranges also decreased the hydroperoxides level and augmented the FRAP value in both intra-and extra-cellular assay. CONCLUSION: These findings revealed antioxidant and cytoprotective effects of LF against H(2)O(2)-induced oxidative stress in HUVECs. With regard to the beneficial vascular activity of LF, further investigations are suggested for understanding its clinical value in human endothelial dysfunction and prevention and/or treatment of CVDs.