中药药理与临床

目的:探讨鸢芩胶囊对脂多糖(LPS)诱导的小鼠急性肺损伤的作用机制及肠道菌群的影响。方法:36只雄性C57BL/6J小鼠随机分为正常对照组、模型对照组、醋酸泼尼松50 mg/kg组、鸢芩胶囊1.95、3.90、7.80 g/kg组，采用气管滴注LPS构建急性肺损伤(ALI)模型。测定肺泡灌洗液(BALF)中细胞总数和白细胞数量；HE染色观察肺组织病理变化；ELISA法检测肺组织中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)含量；Western blot法检测肺组织中磷脂酰肌醇3-激酶(PI3K)、蛋白激酶B(AKT)及其磷酸化(p-PIK、p-AKT)、IL-6、TNF-α、诱导型一氧化氮合酶(iNOS)、甘露糖受体C型1(MRC1)、精氨酸酶-1(Arg1)蛋白表达；16S rRNA基因测序技术，检测粪便样本中菌群组成及多样性变化。结果:与正常对照组相比，模型对照组BALF中炎症细胞数量、肺损伤评分及IL-6、TNF-α含量均显著升高(P<0.01),肺组织p-PI3K/PI3K、p-AKT/AKT比值及Arg1、MRC1蛋白表达明显下调(P<0.05或P<0.01),iNOS、IL-1β、TNF-α蛋白表达明显上调(P<0.05或P<0.01);与模型对照组相比，鸢芩胶囊1.95 g/kg组肺泡灌洗液中细胞总数和白细胞数量显著降低(P<0.01),鸢芩胶囊1.95、7.80 g/kg组肺损伤评分显著降低(P<0.01),各剂量组肺组织中IL-6含量下降(P<0.01),3.90、7.80 g/kg组TNF-α含量显著降低(P<0.01),鸢芩胶囊7.80 g/kg组肺组织Arg1、MRC1、p-AKT/AKT、p-PI3K/PI3K蛋白表达上调，TNF-α、iNOS和IL-1β蛋白表达下调(P<0.05或P<0.01)。肠道菌群分析显示，鸢芩胶囊7.80 g/kg组能显著重塑ALI小鼠肠道菌群结构，降低菌群多样性，减少脱硫弧菌属、黏液螺旋菌属等促炎菌属丰度，富集阿克曼菌等有益菌丰度，并可能通过调节微生物功能影响炎症与代谢相关通路。结论:鸢芩胶囊可能通过激活PI3K/AKT信号通路，下调肺组织促炎因子表达、上调抗炎相关蛋白Arg1与MRC1表达，并调节肠道菌群结构，从而发挥对急性肺损伤的保护作用。

Objective:To explore the mechanism of action of Yuanqin(鸢芩) Capsules on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice and its effect on the gut microbiota. Methods:Thirty-six male C57BL/6J mice were randomly divided into normal control group, model control group, prednisone acetate 50 mg/kg group, and Yuanqin Capsules 1.95,3.90,and 7.80 g/kg groups. The ALImodel was established by intratracheal instillation of LPS. The total cell count and white blood cell count in bronchoalveolar lavage fluid(BALF) were measured. Hematoxylin and eosin(HE) staining was used to observe the histopathological changes in lung tissue. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in lung tissue. Western blot was used to detect the protein expression levels of phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT) and their phosphorylated forms(p-PI3K,p-AKT),IL-6,TNF-α,inducible nitric oxide synthase(iNOS),mannose receptor type C-1(MRC1) and arginase-1(Arg1) in lung tissue. 16S rRNA gene sequencing was used to detect the composition and diversity of the gut microbiota in fecal samples. Results:Compared with the normal control group, the model control group exhibited significantly increased inflammatory cell count in BALF,lung injury score, and IL-6 and TNF-α levels(P<0.01). The ratios of p-PI3K/PI3K and p-AKT/AKT,as well as the expressions of Arg1 and MRC1,significantly decreased(P<0.05 or P<0.01),while the protein expressions of iNOS,IL-1β and TNF-α were significantly upregulated(P<0.05 or P<0.01). Compared with the model control group, the total cell count and the white blood cell count in BALF significantly decreased in the Yuanqin Capsules 1.95 g/kg group(P<0.01). The lung injury scores significantly decreased in the Yuanqin Capsules 1.95 g/kg and 7.80 g/kg groups(P<0.01). The IL-6 levels in lung tissue were reduced in all dosage groups(P<0.05 or P<0.01). TNF-α levels significantly decreased in the Yuanqin Capsules 3.90 g/kg and 7.80 g/kg groups(P<0.01). In the Yuanqin Capsules 7.80 g/kg group, the protein expression levels of Arg1,MRC1,and the ratios of p-AKT/AKT and p-PI3K/PI3K were upregulated(P<0.05 or P<0.01),while the protein expression levels of TNF-α,iNOS and IL-1β were downregulated(P<0.05 or P<0.01). Gut microbiota analysis showed that the Yuanqin Capsules 7.80 g/kg group significantly remodeled the gut microbiota structure in ALI mice, reduced microbiota diversity, decreased pro-inflammatory genera such as Desulfovibrio and Mucispirillum,and enriched beneficial bacteria such as Akkermansia. It was also suggested that microbial functions related to inflammation and metabolic pathways might be modulated. Conclusion:Yuanqin Capsules may exert a protective effect against ALI by activating the PI3K/AKT signaling pathway, downregulating the expression of pro-inflammatory factors, upregulating the anti-inflammatory proteins Arg1 and MRC1 in lung tissue, and modulating the structure of the gut microbiota.