Abstract: To investigate the protective effects and potential mechanism of curcumin against H₂O₂-induced oxidative injury in HT29 Cells.A model of H₂O₂-induced injury in HT29 Cells was successfully established.Cells were divided into control group,model group,curcumin ((low,medium and high concentrations)groups.The optimal damage concentration and time of H₂O₂,and the effect of curcumin (2.5,5,10 μmol/L) on the activity of H₂O₂-induced HT29 cells were determined by MTT assay.The apoptotic rate of HT29 cells was detected by Annexin V/ Propidium iodide staining.HT29 cell cycle alteration was analyzed by Propidium iodide staining.ROS production was assessed by DCFH-DA fluorescence.Mitochondria membrane potential was determined by JC-1 staining.The activities of malondialdelyde (MDA),superoxide dismutase (SOD),caspase-9 and caspase-3 were measured by the spectrophotometric method.Compared with H₂O₂model group,the cell in Curcumin groups exhibited significantly increased viability (P<0.05,P<0.01),decreased apoptosis index (P<0.01),increased proliferation index (P<0.05,P<0.01),decreased intracellular ROS (P<0.05,P<0.01),increased mitochondrial membrane potential (P<0.01),and enhanced caspase-9 and caspase-3 activity (P<0.01).In addition,curcumin groups reduced LDH leakage(P<0.05,P<0.01),inhibited MDA formation(P<0.01) and increased SOD levels(P<0.01).Curcumin has favorable protective effect on H₂O₂-induced HT29 cell injury in a certain dose range,which may be related to scavenging ROS,alleviating DNA oxidative damage and inhibiting mitochondrial pathway-mediated apoptosis.

Key words: curcumin, H₂O₂, HT29 cell, oxidative stress