活性多酚化合物LM49对RAW264.7巨噬细胞极化的影响

目的初步探讨LM49(2,4'三羟基-5,2'-二溴二苯甲酮)对脂多糖(LPS)联合干扰素γ(IFN-γ)诱导的小鼠单核巨噬细胞(RAW264.7)M1/M2极化的影响及其调控机制。方法四曱基偶氮唑蓝(MTT)法测定LM49对细胞活力的影响;流式细胞术、实时荧光定量聚合酶链反应(PCR)和Westem-blot法测定LM49(5,10,20μmol·L^-1)与LPS/INF-γ共同作用于RAW264.7细胞后,巨噬细胞亚型标志物的表达情况及对核因子(NF)-κB和JAK/STAT信号通路的影响。结果与LPS/INF-γ造模组相比,LM49显著抑制CD16/32^+细胞数及诱导型一氧化氮合酶(iNOS)、白细胞介素(IL)4和肿瘤坏死因子(TNF)-αmRNA的表达,升高CD206^+细胞数及Arg-1和IL-10 mRNA的表达,且降低巨噬细胞M1/M2的比值;Westem-blot法验证LM49可显著降低TLR4、Myd88、NF-κB和STAT1蛋白的表达量,同时抑制p-JAK2和p-STATl蛋白磷酸化水平。结论LM49通过抑制TLR4-Myd88-NF-κB和JAK2-STAT1信号通路,抑制巨噬细胞Ml型极化及促进巨噬细胞M2型极化,调节巨噬细胞M1/M2的平衡。

Effect of an Active Polyphenol Compound LM49 on Polarization of RAW264.7 Macrophages

OBJECTIVE To investigate the effect of LM49(2,4',5'-trihydroxy-5,2'-dibromobenzophenone)on M1/M2 phenotype in RAW264.7 macrophages by LPS plus INF-γand its regulation mechanism on M1/M2 polarization.METHODS MIT assay was used to determine the effect of LM49 on cell viability.Different concentrations of LM49(5,10,20μmol·L^-1)were used to intervene in LPS combined with IFN-γinduced macrophages,the expression of macrophage subsets of markers and the effect on JAK/STAT of the signaling pathway were examined by flow cytometry,RT-PCR and Western-blot.RESULTS Compared with LPS/INF-γgroup,LM49 significantly inhibited the number of GD16/32^+cells and the mRNA expression of iNOS,IL-6 and TNF-α,increased the number of CD206^+cells and the mRNA expression of Arg-1 and IL-10,and decreased the ratio of M1/M2 in macrophage.It was demonstrated that LM49 significantly reduced the proteins expression levels of TLR4,Myd88,NF-κB and STAT1,while inhibiting the phosphorylation levels of p-JAK2 and p-STAT1 by Western-blot.CONCLUSION The study demonstrates that LM49 inhibits M1 polarization and promotes M2 polarization in RAW264.7 macrophages via inhibiting TLR4-Myd88-NF-κB and JAK2-STAT1 pathway,regulating the balance of M1/M2 ratio in macrophages.