间歇性缺氧对睡眠呼吸暂停大鼠模型肠道菌群结构的影响

Intermittent hypoxia induce the change of gut microbiota in OSAS rat models

目的探讨间歇性缺氧(IH)对睡眠呼吸暂停综合征(OSAS)大鼠模型肠道菌群结构的影响。方法16只大鼠随机均分为两组,分别给予4周常氧处理(NC组)或间歇性缺氧处理(IH组)。然后采集并提取大鼠粪便DNA,进行16S rRNA焦磷酸测序,并对测序结果进行生物信息学分析。Welch T检验分析两组间样本α多样性差异,ANOSIM分析检验组间β多样性差异,KW秩和检验分析组间显著丰度差异。结果IH组与NC组间OTUs数量无显著差异(P>0.05)。且群落多样性(Shannon指数)和丰富度(Chao1指数)亦无显著差异(P>0.05)。物种差异分析显示,在门水平,拟杆菌门(P<0.05)、软壁菌门(P<0.01)在IH组肠道中显著富集,而厚壁菌门(P<0.05)在NC组肠道中显著富集,但并未发现IH对大鼠肠道内变形菌门(P>0.05)物种丰度的影响。在科水平上,优势菌科中,普雷沃氏菌科(P<0.05),克里斯滕森菌科(P<0.001),韦荣球菌科(P<0.05),柔膜细菌RF9(P<0.01)在IH组显著富集,理研菌科(P<0.001),乳杆菌科(P<0.01)在NC组显著富集。弱势菌科中,产碱菌科(P<0.01),红螺菌科(P<0.05),vadinBE97(P<0.05)IH组显著富集。网络分析显示,IH组和NC组间有广泛的物种之间的相互作用。结论间歇性缺氧可以显著改变大鼠肠道菌群结构特征。

Objective The purpose of the present study was to investigate the influence of intermittent hypoxia on gut microbiota in OSAS rat models.Methods 16 rats were randomly divided into the normoxic group(NC group)and the intermittent hypoxia group(IH group),with 8 rats in each group.At the end of the 4-week intermittent hypoxia or normoxic treatment experiment,feces of each rat were collected to extract DNA.Microbiome composition was determined by 16S rRNA pyrosequencing and bioinformatic analysis.Welch T test and ANOSIM was used to analyzeαdiversity andβdiversity between the two groups,respectively.KW sum-rank test was conducted to analyze abundance difference between the two groups.Results There is no significant difference in the number of OTUs between IH group and NC group(P>0.05).And no significant differences in community diversity(Shannon index)and community richness(Chao1 index)between the two groups were found(P>0.05).Then the structure of the gut microbiome was examined by Lefse software and the LDA score was used to estimate the effect of abundance of each species on the difference between IH group and NC group.The results showed that,at the level of phylum,Bacteroidetes(P<0.05)and Tenericutes(P<0.001)were significantly enriched in IH group,while Firmicutes(P<0.05)were significantly enriched in NC group.However,We found no significant difference between IH and NC groups in terms of the abundance of Proteobacterias(P>0.05).At the family level,among the 12 dominant bacteria,Prevotellaceae(P<0.05),Christensenellaceae(P<0.001),Erysipelotrichaceae(P<0.05),Mollicutes_RF9(P<0.01)were significantly enriched in IH group,while Rikenellaceae(P<0.001)and Lactobacillaceae(P<0.01)were significantly enriched in NC group.In the disadvantaged bacteria,Alcaligenaceae(P<0.01),Rhodospirillaceae(P<0.05),vadinBE97(P<0.05)showed significant enrichment in IH group.Network analyses and single factor correlation network analysis revealed extensive interactions among the identified species between the IH and NC groups.Conclusion Although intermittent hypoxia did not change the community diversity and richness,it has a significant influence on the structure of the gut microbiome in OSAS rat model.