Effect of Astragaloside Ⅳ on lipopolysaccharide-induced macrophages M1/M2 polarization and related mechanism
LU Fu-tai,YANG Tao,LI Man
Department of Anesthesiology, Tianjin Union Medical Center, Tianjin300121, China
Abstract:
Objective To evaluate the effect of Astragaloside Ⅳ (AS-Ⅳ) on lipopolysaccharide (LPS)-induced macrophages M1/M2 polarization and related mechanism. Methods Mouse monocyte-derived macrophages RAW264.7 were cultured in vitro and were randomly divided into 3 groups: control group (group C), LPS group (group LPS) and AS-Ⅳ treatment group (group AS-Ⅳ). In group C, cells were cultured in the common culture medium. In group LPS, 100 ng/mL LPS was added into the culture medium for 24 h incubation. In group AS-Ⅳ, 100 ng/mL LPS and 200 μg/mL AS-Ⅳ were added into the culture medium for 24 h incubation. The levels of IL-1β, IL-10 and IL-18 in culture medium were measured by ELISA assay. The mRNA levels of CD86, CD11c, CD206 and Arginase-1(Arg-1) were measured by qRT-PCR assay. The percentage of CD86(+) and CD206(+) cells was assessed by flow cytometry. The expression levels of nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) and apoptosis-associated speck-like protein (ASC) were detected by Western blot assay. Results Compared with group C, the levels of IL-1β and IL-18, the mRNA levels of CD86 and CD11c, the percentage of CD86(+) cells and the expression levels of NLRP3, ASC and caspase-1 were increased, while the level of IL-10 and the mRNA levels of CD206 and Arg-1, and the percentage of CD206(+) cells were decreased in group LPS(P <0.05). Compared with group LPS, the levels of IL-1β and IL-18, the mRNA levels of CD86 and CD11c, the percentage of CD86(+) cells and the expression levels of NLRP3, ASC and caspase-1 were decreased, while the level of IL-10 and the mRNA levels of CD206 and Arg-1, and the percentage of CD206(+) cells were increased in group AS-Ⅳ(P <0.05). Conclusion AS-Ⅳ can inhibit LPS-induced macrophages M1 polarizaion and promote macrophages M2 polarizaion, whose mechanism may be associated with down-regulating NLRP3 inflammasome expression.
