α-亚麻酸通过调节Th17减轻鲍曼不动杆菌感染小鼠的肺部炎症  

α-linolenic acid alleviates pulmonary inflammation induced by Acinetobacter baumannii by modulating Th17 cell

作　　者：张鼎 张慧[1] 朱云竹 李家斌[1] 叶英[1] Zhang Ding;Zhang Hui;Zhu Yunzhu;Li Jiabin;Ye Ying(Department of infectious diseases,the First Affiliated Hospital of Anhui Medical University,Hefei 230022)

机构地区：[1]安徽医科大学第一附属医院感染病科,合肥230022

出　　处：《中国抗生素杂志》2024年第10期1183-1191,共9页Chinese Journal of Antibiotics

基　　金：国家自然科学基金(No.82304209)。

摘　　要：目的探究α-亚麻酸(ALA)在鲍曼不动杆菌(Acinetobacter baumannii,AB)小鼠肺炎中的作用机制。方法12只BALB/c小鼠随机分成野生组和肺炎组,分别利用靶向代谢组学技术和转录组学技术分析野生组和肺炎组小鼠的血清和肺组织中差异代谢物和差异基因。另取18只BALB/c小鼠随机分为空白组(vehicle组)、A.baumannii感染组(A.baumannii组)和实验组(A.baumannii+ALA组)。空白组和A.baumannii感染组给予普通饮食28 d,实验组给予定制饲料(含5%ALA)喂养28 d,第28天时A.baumannii感染组和实验组给予鲍曼不动杆菌悬液滴鼻,空白组给予PBS缓冲液滴鼻。24h后取小鼠肺组织,采用苏木精-伊红(HE)染色法观察肺组织病理学变化、酶联免疫吸附(ELISA)法测定肺组织炎症因子;流式细胞术和免疫荧光技术检测肺组织辅助性T细胞17(Th17)比例。体外评估ALA对于Th17细胞的影响时,设立ALA组(添加100μmol/L ALA)和对照组(添加相同体积PBS)并用流式细胞术分析Th17细胞比例。结果代谢组学显示,肺炎组小鼠血清的ALA水平显著低于野生组[(3.19+0.76)μg/mL比(10.32+1.75)μg/mL,P<0.0001]。转录组学显示,肺炎组小鼠的肺组织IL-17信号通路中有32个差异基因,其中包括28个上调基因和4个下调基因。在添加ALA的小鼠实验组中,实验组肺组织病理感染严重程度相比于A.baumannii感染组明显减轻,肿瘤坏死因子α(TNF-α)、白介素(IL)-1β、IL-17A水平和Th17细胞比例相比于A.baumannii感染组有明显降低(均P<0.05),IL-6和IL-10水平相对于A.baumannii感染组明显升高(均P<0.05)。在体外分化实验中,ALA组Th17细胞比例明显低于对照组(P<0.05)。结论AB肺炎小鼠血清ALA水平低下,补充ALA后通过抑制Th17分化,对鲍曼不动杆菌所致肺炎具有保护作用,提示膳食补充ALA对鲍曼不动杆菌感染的控制具有一定益处。Objective To investigate the mechanism ofα-linolenic acid on A.baumannii-infected pneumonia in mice.Methods A total of 12 BALB/c mice were randomly divided into two groups:The wild group and the pneumonia group.The differential metabolites and genes in the serum and lung tissues of the wild group and pneumonia group were analyzed by targeted metabonomics technology and RNA sequencing technology,respectively.In addition,18 BALB/c mice were randomly divided into three groups:The blank group(vehicle group),the A.baumannii-infected group(A.baumannii group)and the experimental group(A.baumannii+ALA group).The vehicle group and A.baumannii group were given the regular diet for 28 days,while the A.baumannii+ALA group was given customized feed(including 5%ALA)for 28 days.On day 28,the A.baumannii group and the A.baumannii+ALA group were given A.baumannii through intranasal infection,and the vehicle group was given phosphate buffer solution through intranasal administration.After 24 hours,the lung tissues were collected.Histopathological changes in lung tissues were determined by using hematoxylin and eosin staining.Pulmonary inflammatory cytokines were determined by enzyme-linked immunosorbent assay.Flow cytometry analysis and immunofluorescence techniques were performed to determine the proportion of T helper cells 17(Th17)in lung tissue.To evaluate the effect of ALA on Th17 cells in vitro,the ALA group(adding 100μmol/LALA)and the control group(adding the same volume of PBS)were set up and analyzed by flow cytometry analysis.Results Metabonomics showed that the serum ALA level in the pneumonia group was significantly lower compared with the wild group[(3.19+0.76)μg/mL vs.(10.32+1.75)μg/mL,P<0.0001].Transcriptomics showed that there were 32 differential genes in the IL-17 signaling pathway in the lung tissues of mice in the pneumonia group,including 28 up-regulated genes and 4 down-regulated genes.Compared with the A.baumannii group,the A.baumannii+ALA group alleviated pulmonary histopathological condition,the expres

关 键 词：鲍曼不动杆菌 Α-亚麻酸 TH17细胞 IL-17A 

分 类 号：R563.1[医药卫生—呼吸系统]