Attenuation of oxidative stress of erythrocytes by the plant-derived flavonoids vitexin and apigenin.

Vitexin belongs to the flavonoid carbon glycosides, apigenin is its aglycone. Studies have shown that both of them have antiviral, antioxidant and anticancer effects in vivo and in vitro, but the protective effects on human erythrocytes have not been reported. We studied and compared the protective effects of vitexin and apigenin against H2O2-induced oxidative damage in human erythrocytes and explored the structure-activity relationships. The experiment established the H2O2-induced oxidative damage model, with vitamin C (VC) as a positive comparison, to observe the changes of sulfhydryl content in the red cell membrane protein, erythrocyte morphology and membrane skeleton ultrastructure after oxidative damage. Research results showed that vitexin and apigenin could significantly reduce the degree of hemolysis, lower MDA content, and enhance the activities of erythrocyte antioxidant enzymes. In addition, vitexin and apigenin could restore cell surface morphology through protecting the sulfhydryl content in the red cell membrane protein. Among them, antioxidant capacities of apigenin at doses of 15 and 30 μg/ml were better than that of the same doses of vitexin, while effects of 60 μg/ml vitexin and 30 μg/ml apigenin were the same as 30 μg/ml VC. In conclusion, both vitexin and apigenin have protective effects against H2O2-induced oxidative damage of erythrocytes, which might be achieved through directing subdue oxygen free radical and protecting the antioxidant enzyme activity in cells and the sulfhydryl in the red cell membrane protein.