Effect of Soybean Peptides against Hydrogen Peroxide Induced Oxidative Stress in HepG2 Cells via Nrf2 signaling

The aim of this study was to determine the effects of soybean protein hydrolysates against intracellular antioxidant activity. Soybean peptides (1000 to 2000Da range) were extracted by soybean proteolysis, ultrafiltration and sequenced with the nano-LC-ESI-MS/MS. In this study we found that soybean peptides induced by hydrogen peroxide (H2O2) in HepG2 cells inhibited the production of reactive oxygen species (ROS), malondialdehyde (MDA) and oxidized glutathione (GSSG). Moreover, it also prevented the reduction of reduced glutathione (GSH), and up-regulated cellular resistance oxidase activity. In addition, soybean peptides treatment stimulated mRNA and protein expression levels of antioxidant enzymes and nuclear factor E2 related factor 2 (Nrf2). Activated Nrf2 up-regulated antioxidant enzyme activities (SOD, CAT and GSH-Px) and inhibited ROS and MDA production. It was concluded that soybean peptides effectively activated the Nrf2/antioxidant response element (ARE) mediated activity.