Effect of paeoniflorin on TLR2/4 pathwayin AGEs-induced RAW264.7 macrophages / 中国药理学通报

ABSTRACT

Aim To investigate the effect of paeoniflorin(PF)on TLR2/4 pathway in AGEs-induced RAW264.7 macrophages.Methods RAW264.7 macrophages were incubated at different time points in AGEs stimulation,as well as different concentrations of PF,to optimize experimental conditions.RAW264.7 macrophages were randomly divided into five groups: control group(DMEM),bull serum albumin(BSA)group(200 mg·L-1 BSA),AGEs group(200 mg·L-1 AGEs),paeoniflorin group(200 mg·L-1 AGEs+10-5 mol·L-1 PF)and TLR2/4 inhibitor group(200 mg·L-1 AGEs+30 mg·L-1 OxPAPC).The expression of Toll-like receptor 2(TLR2),Toll-like receptor 4(TLR4),myeloid differentiation factor 88(MyD88),p-IRAK1,TIR-domain containing adaptor protein-inducing IFN-β(TRIF),interferon regulatory factor 3(IRF3),p-IRF3,NF-κB p-p65,NF-κB p65,inducible nitric oxide synthase(iNOS),tumor necrosis factor-α(TNF-α),interleukin-l β(IL-1β)and monocyte chemotactic protein-1(MCP-1)were measured by Western blot.Real-time PCR was used to detect the expression of TLR2 and TLR4 mRNA,while TNF-α,IL-1β and MCP-1 levels in cell supernatant were measured by ELISA.Results Compared with control group,AGEs significantly increased the expression of TLR2,TLR4,MyD88,p-IRAK1,TRIF,IRF3,p-IRF3,NF-κB p-p65,NF-κB p65,iNOS,TNF-α,IL-1β and MCP-1 proteins(P<0.01),as well as TLR2 and TLR4 mRNA(P<0.01).TNF-α,IL-1β and MCP-1 contents were also elevated in cell supernatant(P<0.01).The effects induced by AGEs were decreased significantly in PF and TLR2/4 inhibitor group(P<0.01).Conclusion PF plays an anti-inflammatory effect via inhibiting TLR2/4 pathway on macrophages,which may provide a new theoretical basis for the treatment of diabetic nephropathy.