Xuebijing Injection Promotes M2 Polarization of Macrophages and Improves Survival Rate in Septic Mice

Xuebijing (XBJ) injection, a concoction of several Chinese herbs, has been widely used as animmunomodulator for the treatment of severe sepsis in China. However, the precise mechanismsresponsible for its efficacy have not been fully elucidated. In our study, we determined the flowcytometry markers (F4/80, CD11c, and CD206), the levels of secreted cytokines (TNF-α, IL-6, andIL-10), and the expression of specific proteins of M2 (Ym1, Fizz1, and Arg1) to assessmacrophage polarization. Treatment with XBJ lowered M1 associated cytokine levels andincreased the level of M2 associated cytokine level. The percentage of M2 phenotype cells of XBJgroup was much higher than that of the control group. Expressions of phosphorylated Janus kinase1 (JAK1) and signal transducer and activator of transcription 6 (STAT6) were markedly enhancedafter the administration of XBJ; on the other hand, the M2 associated cytokines and proteins weredecreased following treatment with JAK1 or STAT6 inhibitor. In addition, the treatment of XBJsignificantly improved the survival rate of septic mice. These studies demonstrate that XBJ canmarkedly promote M2 polarization and improve the survival rate of septic mice, therebycontributing to therapeutic effect in the treatment of septic complications.