: This paper seeks to provide mechanistic insight into the pathological transition through the analysis of metabolites and microorganisms in the tongue coating of gastric precancerous lesions (GPL) patients.: GC-TOF-MS and UHPLC-QE-MS metabolomics, combined with 16S rRNA microbiome techniques, were performed to explore the changes in metabolites and microorganisms in the tongue coating of GPL patients.: When compared with 15 controls, 133 metabolites were found to be differentially expressed in 60 GPL cases, of which could be divided into ten categories. Among them, most of the differentially expressed metabolites identified were lipids or lipid-like molecules. These metabolites were implicated in 6 metabolic pathways including glycine, serine and threonine metabolism, arginine and proline metabolism, sphingolipid metabolism, valine, leucine and isoleucine degradation, arachidonic acid metabolism, and tyrosine metabolism. The relative abundances of Alloprevotella, Solobacterium, Rothia, Eikenella, and Aggregatibacter in the GPL group increased significantly relative to the controls and were associated with lipids and lipid-like molecules, organic nitrogen compounds, organic oxygen compounds, phenylpropanoids and polyketides, and organoheterocyclic compounds, respectively.: Compared with healthy people, the changes of tongue coating metabolites in GPL patients were mainly characterized by alterations in lipid metabolism and were associated with localized changes in the microbiome.

ETHNOPHARMACOLOGICAL RELEVANCE:Tongue coating diagnosis is a useful tool to examine the changes of a human body in Chinese Medicine. Tongue coating varies in thickness in kidney disease. However, little information exists regarding the association between clinical characters and tongue coating thickness in CKD patients. AIM OF THE STUDY:This study was carried out to determine whether there is an association between tongue coating thickness and laboratory, histological variables in idiopathic membranous nephropathy patients: one group with thin tongue coating, the other with thick tongue coating. MATERIALS AND METHODS:During July 2012-March 2014, idiopathic membranous nephropathy patients(CKD 1-2 stage) with tongue coating thickness Score ≤7, or ≥11, were enrolled as thin tongue coating group or thick tongue coating group, from Hangzhou Hospital of TCM. Laboratory variables (Hemoglobin (Hb), albumin (Alb); eGFR; alanine transferase (ALT); aspartate aminotransferase (AST); triglyceride (TG); total cholesterone (TC); high density lipoprotein (HDL); low density lipoprotein (LDL); immunoglobin A, G, M; Complement 3, 4) and renal histological data (glomerular lesions; tubular-interstitial damage) were compared, between these two groups. RESULTS:12 idiopathic MN patients (CKD 1-2 stage) with thin tongue coating (tongue coating thickness score ≤7) and 11 with thick tongue coating (tongue coating thickness score ≥11) were enrolled in our study. We found a significant lower level of TC and LDL, a significant lower level of AST, ALT in those thick tongue coating patients, compared with thin. No significant difference was observed in pathological lesion between thick and thin tongue coating patients. CONCLUSION:Tongue coating thickness is associated with lipid metabolism in idiopathic MN patients (CKD 1-2 stages).