The regulatory effect of cardamonin on TLR4/MyD88/NF-κB/iNOS pathway / 中国药理学通报

ABSTRACT

Aim Toassesstheregulatoryeffectsofcar-damonin (CDN ) on toll-like receptor (TLR )-4/MyD88/NF-κB/iNOS signaling pathway in lipopolysac-charide (LPS )-stimulated RAW264. 7 macrophage cells.Methods LPS-stimulatedRAW264.7cells were divided into three groupsvehicle-treated group, LPS-treated group and LPS +CDN-treated group.Cell viability was assessed by CCK-8 assay.The concentra-tion of nitric oxide (NO)in cell culture medium was measured by Griess reagent.The mRNA levels of iN-OS,COX-2,MCP-1 ,TNF-α,IL-6 and IL-1βwere de-termined by reverse transcription real-time quantitative PCR(RT-qPCR).The protein levels of inducible nitric oxide synthase(iNOS),TLR4,myeloid differentiation factor 88(MyD88),nuclear factor κB(NF-κB)phos-phorylated (p )-p65 ,inhibitor κBα(IκBα),and p-IκBαweredeterminedbyWesternblot.Results 1~50 μmol·L-1 CDN had no cytotoxicity in RAW264. 7 cells.However,CDN inhibited the LPS-induced secre-tion of nitric oxide(NO)and mRNA expressions of iN-OS,COX-2,MCP-1 ,TNF-α,IL-6 and IL-1βin a dose-dependent manner.Moreover,50 μmol · L-1 CDN inhibited the LPS-induced up-regulation of iNOS, TLR4,MyD88,NF-κB p-p65,p-IκBαand down-reg-ulationofIκBα.Conclusion Cardamonininhibitsthe production of NO via a mechanism associated with the inhibition of TLR4/MyD88/NF-κB/iNOS pathway.