Effect of an Active Polyphenol Compound LM49 on Polarization of RAW264.7 Macrophages / 中国药学杂志

ABSTRACT

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-γ and its regulation mechanism on M1/M2 polarization. METHODS MTT assay was used to determine the effect of LM49 on cell viability. Different concentrations of LM49 (5, 10, 20 μmol•L-1) were used to intervene in LPS combined with IFN-γ induced 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-γ group, LM49 significantly inhibited the number of CD16/32+ 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.