TABLE 1.
Summary of metabolite variations for different types of biological samples in selected studies.
| Groups | Sample | Investigative methodology | Levels of metabolites |
References | |
| ↑ | ↓ | ||||
| U-CD vs. HC | Stool | GC-MS | p-Cresol, acetone, sulcatone, 2-methyl-butanal, 3-methyl-butanal, carbon disulfide, dimethyl trisulfide, acetic, butyric, valeric acids | Dimethyl trisulfide, dimethyl disulfide, ethyl-acetate, octyl-acetate, 3-methyl-2-oxobutanoic acid, propyl-butanoate, propyl-propanoate, butyl-2-methylbutanoate, glucose, glutamine, Crn | Di Cagno et al., 2009 |
| U-CD vs. HC | Serum | GC-MS | Palmitic, palmitoelic, stearic, oleic acids | Linoleic, alpha-linoleic, arachidonic, eicosapentaenoic, docosapentanoic, docosahexanoic acids | Solakivi et al., 2009 |
| U-CD vs. HC | Serum | H-NMR | Glucose, 3-hydroxybutanoic acid | Lipids, pyruvate, glycoproteins | Bertini et al., 2009 |
| Urine | IS, Cho, acetoacetate, acetic, propanoic acids | ||||
| U-CD vs. HC | Serum | Spectrophotometer-based assay | Total cholesterol | Lewis et al., 2009 | |
| U-CD vs. HC | Stool | GC-MS | Iso-caproic, iso-valeric, iso-butyric, acetic acids | Tjellström et al., 2010 | |
| U-CD vs. HC | Urine | Spectrophotometer-based assay | NO2, NO3 | Högberg et al., 2011 | |
| U-CD vs. HC | Serum | H-NMR | Glucose, 3-hydroxybutanoic acid | Lipids, pyruvate, glycoproteins, Cho, Crn, iso-Leu, Leu, Met, Val | Bernini et al., 2011 |
| Urine | IS, Cho, acetoacetate, acetic, propanoic acids | ||||
| U-CD vs. HC | Serum | H-NMR | Lactic acid, valine, lipids | Fathi et al., 2013 | |
| U-CD vs. HC | Stool | GC-MS | Acetic, propionic, butyric acids | Caminero et al., 2015 | |
| U-CD vs. HC | Plasma | H-NMR | Ala, Gly, Ace, Cr | Crn | Upadhyay et al., 2015 |
| U-CD vs. HC | Stool | HPLC-diode-array detection | Acetic, propionic acids | Primec et al., 2016 | |
| U-CD vs. HC | Stool | GC-MS | ** | ** | Niccolai et al., 2019 |
| U-CD vs. HC | Stool | GC-MS | Acetic acid | Free sulfides, ammonia, L-lactic, propionic, butyric, valeric acids | Zafeiropoulou et al., 2020 |
| U-CD vs. HC | Plasma | H-NMR | Pro, Gly, Arg, Ala, Glu, Cr, Crn, Cys, glucose, lactate, acetate, acetoacetate, β-hydroxybutyrate, pyruvate, succinate, citrate, phosphocreatine | Cho | Upadhyay et al., 2020 |
| Urine | Pro, Trp, β-hydroxybutyrate, pyruvate, succinate, allantoin, aminohippurate | N-methylnicotinamide | |||
| U-CD vs. HC | Stool | HPLC-MS | Xanthurenic, kynurenic acids | Trp, tryptamine, indole-3-aldehyde, indole-3-lactic acid | Lamas et al., 2020 |
| U-CD vs. HC | Sera | GC-MS | Butyric, iso-valeric, butyric (2-methyl), heptanoic, dodecanoic, tetradecanoic, hexadecanoic, octadecanoic acids | Acetic, propionic, valeric acids | Baldi et al., 2021 |
| U-CD vs. HC | Serum | HPLC-MS | HDL-cholesterol, apolipoprotein-AI, retinol | Jamnik et al., 2018 | |
| Short-term GFD | |||||
| U-CD vs. T-CD | Serum | GC-FID | Steric, arachidonic, docosapentanoic, docosahexanoic acids | Solakivi et al., 2009 | |
| U-CD vs. T-CD | Stool | H-NMR | Butyric, valeric, acetic, propionic acids | Tjellström et al., 2014 | |
| U-CD vs. T-CD (oat-based GFD) | Stool | H-NMR | Butyric, valeric, acetic, propionic acids | Tjellström et al., 2014 | |
| Long-term GFD | |||||
| T-CD vs. U-CD | Serum | Spectrophotometer-based assay | HDL-cholesterol | Lewis et al., 2009 | |
| T-CD vs. U-CD | Serum | Spectrophotometer-based assay | HDL-cholesterol | De Marchi et al., 2013 | |
| T-CD vs. U-CD | Serum | Spectrophotometer-based assay | Vitamins (A, B12, D, E), zinc, ferritin, iron | Deora et al., 2017 | |
| T-CD vs. U-CD | Stool | HPLC-MS | Indole-3-acetic acid | Lamas et al., 2020 | |
| T-CD vs. HC | Stool | GC-MS | Propanone, butyric, valeric acids | Total esters, iso-valeric acid | Di Cagno et al., 2009 |
| T-CD vs. HC | Serum | GC-MS | Palmitic, palmitoleic, stearic, oleic acids | Linoleic, alpha-linoleic, arachidonic, eicosapentaenoic, docosapentanoic, docosahexanoic acids | Solakivi et al., 2009 |
| T-CD vs. HC | Stool | H-NMR GC-MS | Carbon disulfides, 1-octen-3-ol, ethanol and 1-propanol, acetic acids | Ethyl-acetate, octyl-acetate, propyl-butyrate, propyl-propanoate, butyl 2-methylbutanoate, iso-caproic, butyric, propanoic acids | Di Cagno et al., 2011 |
| Urine | Dimethyl disulfide, dimethyl trisulfide, Lys, Arg, Cr, methylamine | 3-Methyl-2-oxobutanoic acid, Crn, glucose, glutamine | |||
| T-CD vs. HC | Serum | H-NMR | Cho | Lipids (mainly VLDL), lactate | Rezaei-Tavirani et al., 2012 |
| T-CD vs. HC | Serum | GC-MS | Valeric acid | Acetic acid | Jakobsdottir et al., 2013 |
| T-CD vs. HC | Saliva | GC-MS | Acetic acid, ethyl ester, nonanal, 1-chlorodecane, trichloromethane, carbon disulfide | 2-Ethyl-1-hexanol, 4-(1,1,3,3-tetramethylbutyl)-phenol, ethyl alcohol, butanoic acid 2-methyloctyl ester, thiophenes, ketones, terpenes, 1-octadecene, octanal | Francavilla et al., 2014 |
| T-CD vs. HC | Stool | *** | Propionic, butyric, valeric, iso-butyric, iso-valeric acids | Makinder et al., 2014 | |
| T-CD vs. HC | Stool | GC-MS | ** | ** | Rouvroye et al., 2019 |
| T-CD vs. HC | Plasma | LC-MS | Cysteine, cystathionine | Martín-Masot et al., 2020 | |
| T-CD vs. HC | Stool | HPLC-MS | Trp | Lamas et al., 2020 | |
| T-CD (semi-strict GFD) vs. HC | Serum | Spectrophotometer-based assay | NO2, NO3, NOx | Uspenskaya et al., 2014 | |
| T-CD (semi-strict GFD) vs. T-CD (strict GFD) | Serum | Spectrophotometer-based assay | NO3, NOx | Uspenskaya et al., 2014 | |
| Urine | D-xylose | ||||
| CD infants (weaned-GFD) vs. CD infants (weaned-GCD) | Stool | H-NMR | ** | ** | Sellitto et al., 2012 |
| CD-infants vs. HC infants | Serum | HPLC-MS | ** | ** | Kirchberg et al., 2016 # |
| Infants (enrolled before gluten exposure) | |||||
| U-CD infants vs. HC infants | Serum | UHPLC-MS | Lyso-phosphatidylcholine, alkylacyl-phosphatidylcholine, phosphatidylserine | Phosphatidyletanolamine phosphatidylglycerol | Auricchio et al., 2019 # |
| U-CD infants vs. HC infants | Plasma | UHPLC-MS | Triacylglycerols of low carbon number and double bond count | Phosphatidylcholines | Sen et al., 2019 # |
| U-CD infants vs. T-CD infants | Plasma | UHPLC-MS | Triacylglycerols (essential and nonessential) | Phosphatidylcholines | Sen et al., 2019 # |
For each raw, by referring to the first group reported in the first column, ↑ and ↓ mean a significant increase or decrease, respectively. **No discriminant analyte or significant alteration between groups. ***No methods described. #Longitudinal study. GFD, gluten-free diet; U-CD, active celiac disease subjects; T-CD, GFD-treated celiac disease subjects; HC, healthy controls; GCD, gluten contained diet; GC, gas chromatography; MS, mass spectrometry; H-NMR, nuclear magnetic resonance spectroscopy; LC, liquid chromatography; (U)HPLC, (ultra)high-performance liquid chromatography; Ala, alanine; Arg, arginine; Cho, choline; Cr, creatine; Crn, creatinine; Crn, carnosine; Glu, glutamic acid; Gly, glycine; IS, indoxyl sulfate; Leu, leucine; NOx, nitric oxides; Pro, proline; Trp, tryptophane.