Tongue coating’s metabolic markers in Dampness-heat syndrome of chronic gastritis patients

Objective: The aim of the study was to investigate the characteristic index and metabolic markers of tongue coating in the patients with chronic gastritis (CG). Methods: From October 2014 to July 2015, 24 healthy volunteers and 60 patients with chronic gastritis (30 with the dampness-heat syndrome and 30 with non-dampness-heat syndrome) were enrolled in the study. The metabolites of tongue coating among three groups were measured by gas chromatography/mass spectrometry (GC/MS) method. Results: The characteristics of tongue coating were different among dampness-heat syndrome group, non-dampness-heat syndrome group and control group. The tongue coating was thicker and greasier of the patients with chronic gastritis in dampness-heat syndrome group. Three metabolic markers were detected in tongue coating by gas chromatography/mass spectrometry, accompanied with a retention time of14.994955, 14.47272 and 7.190636 between the dampness-heat syndrome group and non-dampness-heat syndrome group. By searching the NIST2005 database, these three metabolic biomarkers identified as Cystathionine or 3,5-Di-t-butyl-4-hydroxybenzoic acid, ethyl ester; Pyroglutamic acid and Putrescine were closely correlated with the metabolic pathways of the dampness-heat syndrome. Conclusions: The tongue coating of chronic gastritis with dampness-heat syndrome was thicker and greasier. These three metabolites biomarker in dampness-heat syndrome of chronic gastritis may be associated with the synthesis and decomposition of amino acids, suggesting that the pathway of amino acid metabolism may mediate the dampness-heat syndrome of chronic gastritis.