Candesartan inhibits LPS-induced inflammatory cytokines release in VSMCs via TLR4-mediated signaling pathway / 重庆医学

ABSTRACT

Objective To study the effect of candesartan (Can) on the LPS‐induced proinflammatory cytokines release in VSMCs ,and to explore the role of TLR4‐mediated signaling pathway in this process .Methods Rat VSMCs were primarily cul‐tured ,and the effect of different concentrations of Can on VSMCs activity was observed by M TT assay .The cells were divided into 5 groupsA(control) ,B(LPS intervention) ,C(LPS + 10 - 7 mol/L Can) ,D(LPS + 10 - 7 mol/L Can ) and E (LPS + Can 10 - 5 mol/L Can) .mRNA and protein levels of Toll‐like receptor‐4(TLR4) ,myeloid differentiation primary response gene 88(Myd88)and nu‐clear factor‐κB(NF‐κB) nuclear translocation were determined by real‐time PCR and Western blot ,respectively ;IL‐1β and TNF‐αconcentration were detected by ELISA .The production of intercellular reactive oxygen species(iROS) was measured by the DCFH‐DA assay .Pretreating VSMCs with the inhibitors against TLR4 ,NADPH oxidase ,and NF‐κB ,or a combination with candesartan and these inhibitors ,and then the expression of IL‐1β and TNF‐α was measured by ELISA .Results Can in the concentration range of 10 - 8 - 10 - 3 mol/L had no significant effect onVSMCs activity .Compared with th control group ,Can could effectively inhibit LPS‐induced VSMCs ,IL‐1β and TNF‐α release ,decreased the mRNA and protein expression of TLR4 ,Myd88 ,reduced the produc‐tion of iROS ,inhibited the NF‐κB(p65) nuclear translocation with a concentration‐dependent manner(P< 0 .05) .Anti‐TLR4 anti‐body ,DPI ,and PDTC all inhibited LPS‐induced inflammatory cytokines release in VSMCs ,and the combination of Can and these blockers showed stronger anti‐inflammatory effect .Conclusion Can can decrease the releaseof inflammatory cytokines IL‐1β and TNF‐α in VSMCs stimulated by LPS ,which is realized by inhibiting the signaling pathway of TLR4/Myd88‐iROS‐NF‐κB .