Inhibitory Effect of Crude Walnut Leaf Polysaccharides on Oxidative Damage of Proteins and Proliferation of SGC-7901 Cells

In this paper, we studied the inhibitory effect of crude Walnut Leaf Polysaccharides (WLP) on free radical-induced oxidative damage of proteins and anti-proliferation activity on human Gastric Cancer cells (SGC-7901). The oxidative degradation of Bovine Serum Albumin (BSA), mouse brain proteins (MBP) and Mouse Liver Proteins (MLP) induced by hydroxyl radical and alcoxyl radical was analyzed by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). In addition, MTT method was used to analyze the effect of WLP on cell viabilities of SGC-7901 cells. The results indicated that WLP significantly inhibited the oxidative damage of BSA induced by hydroxyl radical within the concentration range of 0.5~20 mg/mL. Similar protective effects were found in hydroxyl radical-induced oxidative damage on mouse tissue proteins. WLP inhibited the oxidative damage of three protein models induced by alcoxyl radical in a dose-dependent manner. Furthermore, WLP inhibited the growth of SGC-7901 cells in time- and concentration-dependent manner. In conclusion, WLP show significant inhibitory effect on protein oxidative damage induced by hydroxyl radical and alcoxyl radical as well as anti-proliferation capacity on SGC-7901 cells.