Study On Antioxidant Effect And Mechanism Of Water Extract Of Cuscuta Seed

Cuscutachinensis(C.chinensis)is a well-known traditional Chinese herb that has been used to treat heart disease,diabetes,liver injury,and aging.In this study,the antioxidant mechanism of C.chinensis was measured.Murine osteoblastic MC3T3-E1 cells and human hepatocyte-derived cell line HL7702 cells were treated with various concentrations of C.chinensis water extraction at different time intervals.The antioxidant effect of C.chinensis on MC3T3-E1 cells and HL7702 cells was evaluated using MTT and TUNEL assays.The effect of C.chinensis on cell cycle was analyzed by flow cytometry with propidium iodide.Lipid peroxidation was measured by HPLC method.The cellular redox status was determined from the reduced glutathione to oxidized glutathione ratio(GSH/GSSG)and the enzymes involved in glutathione metabolism.The changes in relative mitochondrial transmembrane potential(??m)in the MC3T3-E1 cells were analyzed with rhodamine 123 staining.Western blot analysis was used to evaluate the levels of cytochrome c(cyto c),Bax,Bcl-2,caspase 3,Sirt3,and IDH2 expressions.The C.chinensis water extraction protects tertiary butyl hydroperoxide(TBHP)-treated MC3T3-E1 cells and HL7702 cells from death in a dose-dependent manner.C.chinensis treatment significantly inhibited the reactive oxygen species(ROS)generation,malondialdehyde(MDA)production,and increased the activity of SOD,GR,GST,and G6PD.The release of cyto c from mitochondria was reduced by C.chinensis,which increased the expression of antiapoptotic IDH2,Sirt3,and Bcl-2 and decreased the expression of Bax,cyto c,and caspase 3.Taken together,C.chinensis modulated the oxidative stress-induced apoptosis in MC3T3-E1 cells and HL7702 cells,probably due to its antioxidant activity and functioning via mitochondria-dependent pathways.