基于16S rDNA基因测序探讨咳嗽变异性哮喘与肠道菌群的关系

Relationship between Cough Variant Asthma and Intestinal Flora Based on 16S rDNA Gene Sequencing

【目的】基于“肺与大肠相表里”中医理论和16S核糖体DNA(16S rDNA)基因测序技术,探讨卵清蛋白(OVA)诱导的咳嗽变异性哮喘(CVA)对小鼠肠道菌群的影响。【方法】20只BALB/c雌性小鼠随机分为模型组和对照组,以OVA致敏并激发制备CVA小鼠模型。记录小鼠体质量、咳嗽次数及咳嗽潜伏期,肺组织进行病理学检查,16S rDNA高通量测序分析粪便菌群。【结果】与对照组相比,模型组小鼠一般状态较差,躁动不安,抓耳挠腮,体质量下降(P<0.01),咳嗽次数增多(P<0.01),咳嗽潜伏期缩短(P<0.01);病理结果显示模型组小鼠肺部炎性浸润明显,气道平滑肌增厚,上皮细胞坏死等;16S rDNA测序显示模型组小鼠肠道菌群物种丰富度及多样性增加,菌群结构发生显著变化。在门水平上,模型组小鼠厚壁菌门相对丰度下降,拟杆菌门和广古菌门相对丰度增加;在属水平上,模型组乳酸杆菌属下降,甲烷短杆菌属和普雷沃氏菌科UCG-003属相对丰度增加。【结论】OVA诱导的CVA小鼠存在肠道菌群紊乱现象,为治疗CVA提供新的思路,进一步表征“肺与大肠相表里”的中医理论。

【Objective】To explore the effect of ovalbumin(OVA)-induced cough variant asthma(CVA)on the intesti⁃nal flora of mice,based on the traditional Chinese medicine theory of"exterior-interior relationship between the lung and the large intestine"and 16S ribosomal DNA gene sequencing technology.【Methods】Twenty BALB/c female mice were ran⁃domly divided into model group and control group,and were sensitized and stimulated with OVA to establish a CVA mouse model.After modeling,the body weight and the cough response of mice were recorded by ammonia water-induced cough method.Hematoxylin-eosin staining was used to observe the pathological changes in the lungs of mice.The feces of mice were collected for 16S rDNA high-throughput sequencing analysis.【Results】Compared with the control group,the mice in the model group were in a poorer general state,being restless,scratching their ears,and losing weight(P<0.01).The model group mice had increased cough times(P<0.01)and shortened cough latency(P<0.01)in comparison to the control group.Pathological results showed that the model group mice had obvious inflammatory infiltration,thickened airway smooth muscle,and epithelial cell necrosis.16S ribosomal DNA sequencing showed that the species richness and diversity of the intestinal flora of mice in the model group increased,and the structure of the intestinal flora changed significantly.At the phylum level,the relative abundance of Firmicutes in the model group was decreased,and the relative abundance of Bacteroidetes and Euryarchaeota was increased.At the genus level,the relative abundance of Lactobacillus was decreased in the model group,and the relative abundance of Methanobrevibacter and Prevotellaceae UCG-003 was increased.【Conclu⁃sion】OVA-induced CVA mice had intestinal flora disorder,which provides new idea for the treatment of CVA,and fur⁃ther enriches the traditional Chinese medicine theory of“exterior-interior relationship between the lung and the large intes⁃tine”.