甘草酸对体外鸡巨噬细胞免疫和杀菌功能的影响（英文）

Glycyrrhizic acid activates chicken macrophages and enhances their Salmonella-killing capacity in vitro

目的:探究甘草酸能否激活体外鸡巨噬细胞并增强其免疫和吞噬杀菌功能。创新点:甘草酸通过核因子κB(NF-κB)和c-Jun氨基端激酶(JNK)信号通路提高一氧化氮(NO)和过氧化氢(H2O2)产生量,增强了其吞噬和杀菌的功能。方法:以不同浓度的甘草酸(0、12.5、25、50、100、200、400和800μg/ml)处理鸡巨噬细胞系HD11,采用荧光定量聚合酶链式反应(qP CR)和一氧化氮及过氧化氢测定试剂盒评价甘草酸对鸡巨噬细胞活化和免疫的影响,采用流式细胞技术和涂板计数法测定鸡巨噬细胞吞噬和杀菌能力。结论:甘草酸通过NF-κB和JNK信号通路激活鸡巨噬细胞,提高免疫细胞因子等基因的表达水平和NO及H_2O_2的产生量,从而增强了鸡巨噬细胞吞噬和清除胞内沙门氏菌的能力。

Objective： Salmonella enterica remains a major cause of food-borne disease in humans, and Salmonella Typhimurium （ST） contamination of poultry products is a worldwide problem. Since macrophages play an essential role in controlling Salmonella infection, the aim of this study was to evaluate the effect of glycyrrhizic acid （GA） on immune function of chicken HD11 macrophages. Methods： Chicken HD11 macrophages were treated with GA （0, 12.5 25, 50, 100, 200, 400, or 800 pg/ml） and lipopolysaccharide （LPS, 500 ng/ml） for 3, 6, 12, 24, or 48 h. Evaluated responses included phagocytosis, bacteria-killing, gene expression of cell surface molecules （cluster of differentiation 40 （CD40）, CD80, CD83, and CD197） and antimicrobial effectors （inducible nitric oxide synthase （iNOS）, NADPH oxidase-1 （NOX-1）, interferon-γ （IFN-γ）, LPS-induced tumor necrosis factor （TNF）-α factor （LITAF）, interleukin-6 （IL-6） and IL-IO）, and production of nitric oxide （NO） and hydrogen peroxide （H202）. Results： GA increased the internalization of both fiuorescein isothiocyanate （FITC）-dextran and ST by HD11 cells and markedly decreased the intracellular survival of ST. We found that the messenger RNA （mRNA） expression of cell surface molecules （CD40, CDSO, CD83, and CD197） and cytokines （IFN-γ, IL-6, and IL-10） of HD11 cells was up-regulated following GA exposure. The expression of iNOS and NOX-1 was induced by GA and thereby the productions of NO and H202 in HD11 cells were enhanced. Notably, it was verified that nuclear factor-κB （NF-κB） and c-Jun N-terminal kinase （JNK） pathways were responsible for GA-induced synthesis of NO and IFN-γ gene expression. Conclusions： Taken together, these results suggested that GA exhibits a potent immune regulatory effect to activate chicken macrophages and enhances Salmonella-killing capacity.