Anti-inflammatory Effects Of Isoquercitrin On LPS-induced RAW264.7 Cells

Objective:This study aims to clarify the influence of isoquercitrin on inflammatory factors in LPS-induced RAW264.7 cells.Methods:The RAW264.7 cells were divided into 6 experimental groups:control group,LPS group,isoquercitrin plus LPS group and isoquercitrin group.RAW264.7 cells cultured in 6 wells plates at the concentration of 2×106cells per milliliter and 2mL per well.After pre-culture for 24 h,The cells were treated with isoquercitrin 1h before exposured LPS for 48 h in each experiment.Inhibition ratio of Isoquercitrin on the RAW264.7 cells were detected by MTT assay.The level of TNF-α in culture medium were measured by ELISA.NO was deteced by Nitrate Assay Kit.The expression of inducible nitric oxide synthase(iNOS)and cyclooxygenase-2(COX-2)were measured by Western blotting.Results: The half inhibitory concentration(IC50)of isoquercitrin was 65.73 umol/L.LPS had no inhibitory effect on cells.Compared with LPS group,isoquercitrin(20,10μmol·L-1)groups were found to attenuate the level of TNF-α.There was negitave correlation between the level of TNF-α and drug concentration in dose-dependent manner.The results measured by Nitrate Assay Kit revealed that isoquercitrin could suppress production of NO.The Western Blot results showed that isoquercitrin had stronger inhibitions on the expression of iNOS,COX-2.Conclusions:Isoquercitrin had stronger anti-inflammatory effects by inhibiting the productions of TNF-α,NO,iNOS and COX-2,the effective dose for the inhibition is 10μmol·L-1.