夏枯草提取物对脓毒症小鼠炎症反应和腹腔巨噬细胞的影响

The effect of prunella vulgaris extract on inflammatory response and peritoneal macrophages in septic mice

目的探究夏枯草提取物对脓毒症小鼠炎症、巨噬细胞表型及吞噬能力的影响,并分析Toll样受体4(TLR4)/核因子-κB(NF-κB)信号通路是否参与其作用。方法将C57BL/6小鼠分为对照组,模型组,夏枯草提取物低(25 mg/kg)、中(50 mg/kg)、高(100 mg/kg)剂量组。除对照组外,其余各组小鼠腹腔注射脂多糖(LPS)制备脓毒症模型;各组给予相应药物灌胃。给药24 h后,检测小鼠血清肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β、高迁移率族蛋白B1(HMGB1)、IL-10水平,M1型(CD11b^(+)F4/80^(+))和M2型(CD206^(+)F4/80^(+))巨噬细胞占腹腔巨噬细胞的比例及巨噬细胞的吞噬能力,腹腔巨噬细胞诱导型一氧化氮合酶(iNOS)mRNA和精氨酸酶1(Arg1)mRNA表达以及巨噬细胞TLR4、NF-κB p65及其磷酸化蛋白表达。结果与对照组相比,模型组小鼠血清TNF-α、IL-1β、HMGB1,腹腔M1型巨噬细胞比例,巨噬细胞的平均荧光强度和吞噬能力百分比,iNOS mRNA,TLR4、磷酸化NF-κB p65(p-NF-κB p65)/NF-κB p65蛋白表达升高(P<0.05),IL-10、M2型巨噬细胞比例、Arg1 mRNA表达降低(P<0.05);与模型组相比,夏枯草提取物低、中、高剂量组小鼠血清TNF-α、IL-1β、HMGB1,腹腔M1型巨噬细胞比例,iNOS mRNA,TLR4、p-NF-κB p65/NF-κB p65蛋白表达依次降低(P<0.05),IL-10、M2型巨噬细胞比例、巨噬细胞的平均荧光强度和吞噬能力百分比、Arg1 mRNA表达依次升高(P<0.05)。结论夏枯草提取物可能通过抑制TLR4/NF-κB通路抑制腹腔巨噬细胞极化为M1型,并促进其向M2型极化,增强巨噬细胞吞噬能力,减轻LPS诱导的脓毒症小鼠炎症反应。

Objective To investigate the effect of prunella vulgaris extract on inflammation,macrophage phenotype,and phagocytic ability in septic mice,and analyze whether Toll like receptor 4(TLR4)/nuclear factor-κB(NF-κB)signaling pathway involved in its mechanism.Methods C57BL/6 mice were divided into the control group,the model group and the prunella vulgaris extract low(25 mg/kg),medium(50 mg/kg)and high(100 mg/kg)dose groups.Except for the control group,all other groups of mice were injected intraperitoneally with lipopolysaccharide(LPS)to prepare sepsis model.Each group was given corresponding medication by gavage.After 24 hours of administration,serum tumor necrosis factor-α(TNF-α),interleukin(IL)-1β,high mobility group protein B1(HMGB1),IL-10 levels,the proportion of M1 type(CD11b^(+)F4/80^(+))and M2 type(CD206^(+)F4/80^(+))macrophages in peritoneal macrophages,the phagocytotic capacity of macrophages,the expression of inducible nitric oxide synthase(iNOS)messenger RNA(mRNA)and arginase 1(Arg1)mRNA in peritoneal macrophages and expression levels of TLR4,NF-κB p65 and their phosphorylated proteins in macrophages were detected.Results Compared with the control group,serum TNF-α,IL-1β,HMGB1,proportion of M1 type macrophages in abdominal cavity,mean fluorescence intensity and phagocytotic capacity of macrophages,iNOS mRNA,TLR4,phosphorylated NF-κB p65(p-NF-κB p65)/NF-κB p65 protein expression were increased in the model group(P<0.05).IL-10,proportion of M2 type macrophages and Arg1 mRNA expression were decreased(P<0.05).Compared with the model group,serum TNF-α,IL-1β,HMGB1,proportion of M1 type macrophages in abdominal cavity,iNOS mRNA,TLR4,p-NF-κB p65/NF-κB p65 protein expression were decreased successively in the prunella vulgaris extract low,medium and high dose groups(P<0.05).IL-10,proportion of M2 macrophages,mean fluorescence intensity and phagocytotic capacity of macrophages and Arg1 mRNA expression were increased successively(P<0.05).Conclusion By inhibiting TLR4/NF-κB pathway,prunella vulgaris extract may inhibit the polarization of peritoneal macrophages into M1 type and promote their polarization to M2 type,enhance macrophage phagocytic ability and alleviate LPS induced inflammatory response in septic mice.