黄腻苔人群舌苔与肠道菌群微生态特征及其相关性研究

Perturbations in gastrointestinal tract microbiota composition and function in individuals with yellow-greasy tongue coating

目的研究黄腻苔人群的舌苔和肠道微生物菌群结构和代谢特征,探讨黄腻苔人群舌苔和肠道菌群代表性的代谢标志物和代谢通路。方法于2021年12月1日至2022年10月30日采集黄腻苔及薄白苔受试者的舌苔及大便样本。16S rRNA及宏基因组测序技术对2组受试者的舌苔和粪便样本进行菌群鉴定;并对2组样品进行菌群α-多样性分析、主成分分析(PCA)和Spearman相关性分析;超高效液相色谱联用串联质谱(UPLC–MS/MS)进行代谢组学分析及代谢通路富集分析。结果本研究共招募20例黄腻苔受试者和19例薄白苔受试者。在菌群属水平,2组受试者的舌苔菌群及肠道菌群的优势菌种大致相同,但是相对峰度差异明显,黄腻苔受试者舌苔及粪便样本中潜在致病菌丰度较高。黄腻苔受试者的舌苔样品中有9种微生物下调,粪便样品中有26种微生物下调,6种微生物上调。α-多样性分析显示,黄腻舌苔受试者舌苔菌群的Chao和ACE指数有下降趋势,但差异无统计学意义(P>0.05);粪便样本菌群的α-多样性明显降低,Chao和ACE指数显著下降(P<0.05)。主成分分析结果显示,2组受试者的舌苔和粪便样本的菌群结构差异较大。Spearman相关性分析,同一受试者舌苔和粪便微生物在菌种在门和属水平上无相关性(P>0.05)。代谢组学结果显示黄腻苔的舌苔样本中富马酸还原酶、V/A型ATP酶、磷脂酰乙醇胺等含量增加,甘油酸-3P,UDP-葡萄糖和醌氧化还原酶代谢物等代谢物含量减少;大便样本中单磷酸肌苷(IMP)、单磷酸尿苷(UMP)、γ氨基丁酸等含量增加,核糖-5P、组氨酸、生物素、钴胺素等含量减少。代谢通路分析显示黄腻苔的舌苔样本及粪便样本在包括氨基酸代谢、碳水化合物代谢、氮代谢及能量代谢等多种代谢通路相对丰度较低。结论舌苔和肠道微生物群或代谢物的结构和功能的变化可能是黄腻苔形成的潜在生物学基础。

Objective To study the composition and function of tongue coating(TC)and gastrointestinal tract(GIT)microbiota in participants with yellow-greasy tongue coating(YGTC),and to explore the representative metabolite markers and pathways in this group.Methods Subjects with YGTC or thin-white tongue coating(TWTC)were recruited from December 1,2021 to October 30,2022,and the TC and fecal samples were collected.Samples were subjected to both whole-genome shotgun(WGS),and 16S rRNA gene sequencing.Theα-diversity analysis,principal component analysis(PCA),and Spearman correlation analysis were performed for two groups.Ultra-performance liquid chromatography combined with tandem mass spectrometry(UPLC–MS/MS)analysis was used to analyze metabolomics and enrichment of metabolic pathways.Results The results revealed 20 YGTC participates and 19 TWTC participates.At the genus level,the dominant bacterial species of TC flora and intestinal flora in the two groups were roughly the same,but the relative kurtosis difference was marked,and the abundance of potentially pathogenic bacteria in TC and fecal samples of YGTC subjects was higher.There were 9 down-regulated microorganisms in the TC samples,26 down-regulated microorganisms,and 6 up-regulated microorganisms in YGTC subjects.Theα-diversity analysis indicated that the Chao and abundance-based coverage estimator(ACE)indices of TC bacteria in the YGTC subjects showed a decreasing trend,but the difference was not statistically significant(P>0.05).Theα-diversity of fecal samples and the Chao and ACE indices decreased significantly(P<0.05).PCA showed that the microflora structure of TC and fecal samples were significantly different between the two groups.Spearman correlation analysis showed that there was no correlation between TC and fecal microorganisms at phyla and genus levels in the same subjects(P>0.05).The metabolomics results demonstrated that fumarate reductase,V/A ATPase,and phosphatidylethanolamine were increased,and glycerate-3p,UDP-glucose,and quinone oxidoreductase metabolites were decreased in YGTC TC samples.Inosine monophosphate(IMP),uridine monophosphate(UMP),and gamma-aminobutyric acid(GABA)were increased in YGTC fecal samples,while the contents of ribo-5P,histidine,biotin,and cobalamin were decreased.Metabolic pathway analysis indicated that the abundance of the TC and fecal samples of the YGTC subjects was relatively low in various metabolic pathways,including amino acid metabolism,carbohydrate metabolism,nitrogen metabolism,and energy metabolism.Conclusion Structural and functional changes in TC and GIT microbiota or metabolite markers could be potential biological bases of YGTC formation.