Table 2 Plasma metabolites significantly associated with DAS28-CRP

3-Hydroxystearate

Lipid

Fatty acid, monohydroxy

N/A

0.418

0.002

Phenol sulfate

Amino acid

Tyrosine metabolism

HMDB60015

−0.265

0.003

Trimethylamine N-oxide

Lipid

Phospholipid metabolism

HMDB00925

0.485

0.004

Bilirubin (E,E)

Cofactors and vitamins

Hemoglobin and porphyrin metabolism

N/A

−0.612

0.007

Serine

Amino acid

Glycine, serine, and threonine metabolism

HMDB00187

−1.594

0.010

Dimethylguanidino valeric acid (DMGV)

Amino acid

Urea cycle; arginine and proline metabolism

N/A

0.325

0.011

N-acetyltryptophan

Amino acid

Tryptophan metabolism

HMDB13713

−0.918

0.012

Glycoursodeoxycholate

Lipid

Secondary bile acid metabolism

HMDB00708

0.051

0.012

N-acetylneuraminate

Carbohydrate

Aminosugar metabolism

HMDB00230

0.470

0.013

Dihomo-linoleoylcarnitine (C20:2)

Lipid

Fatty acid metabolism (acyl carnitine, polyunsaturated)

N/A

−0.745

0.013

N-acetyltyrosine

Amino acid

Tyrosine metabolism

HMDB00866

−0.713

0.014

Branched chain 14:0 dicarboxylic acid

Lipid

Fatty acid, dicarboxylate

N/A

−0.201

0.014

1-Carboxyethylvaline

Amino acid

Leucine, isoleucine, and valine metabolism

N/A

0.408

0.015

(14 or 15)-methylpalmitate (a17:0 or i17:0)

Lipid

Fatty acid, branched

N/A

0.227

0.017

Isoursodeoxycholate

Lipid

Secondary bile acid metabolism

HMDB00686

0.059

0.018

Glucuronate

Carbohydrate

Aminosugar metabolism

HMDB00127

0.396

0.019

Glucose

Carbohydrate

Glycolysis, gluconeogenesis, and pyruvate metabolism

HMDB00122

1.107

0.019

Linoleoylcarnitine (C18:3)

Lipid

Fatty acid metabolism (acyl carnitine, polyunsaturated)

N/A

−0.534

0.020

1-Methylhistidine

Amino acid

Histidine metabolism

HMDB00001

0.580

0.020

Trigonelline (N′-methylnicotinate)

Cofactors and vitamins

Nicotinate and nicotinamide metabolism

HMDB00875

−0.227

0.020

Palmitoyl ethanolamide

Lipid

Endocannabinoid

HMDB02100

0.067

0.020

Hypoxanthine

Nucleotide

Purine metabolism, (hypo)xanthine/inosine containing

HMDB00157

0.482

0.022

Biliverdin

Cofactors and vitamins

Hemoglobin and porphyrin metabolism

HMDB01008

−0.436

0.022

Linoleoylcarnitine (C18:2)

Lipid

Fatty acid metabolism (acyl carnitine, polyunsaturated)

HMDB06469

−0.814

0.023

3-Methylhistidine

Amino acid

Histidine metabolism

HMDB00479

0.140

0.025

N-acetylarginine

Amino acid

Urea cycle; arginine and proline metabolism

HMDB04620

−0.755

0.026

4-Guanidinobutanoate

Amino acid

Guanidino and acetamido metabolism

HMDB03464

0.347

0.026

1-Carboxyethylisoleucine

Amino acid

Leucine, isoleucine, and valine metabolism

N/A

0.307

0.026

Cysteinylglycine disulfide

Amino acid

Glutathione metabolism

HMDB00709

1.562

0.027

Guanidinoacetate

Amino acid

Creatine metabolism

HMDB00128

−1.125

0.027

N2-acetyl,N6-methyllysine

Amino acid

Lysine metabolism

N/A

−0.213

0.028

Lysine

Amino acid

Lysine metabolism

HMDB00182

−1.395

0.031

1,6-Anhydroglucose

Xenobiotics

Food component/plant

HMDB00640

0.097

0.032

Pyrraline

Xenobiotics

Food component/plant

HMDB33143

0.190

0.032

Mannose

Carbohydrate

Fructose, mannose, and galactose metabolism

HMDB00169

0.633

0.032

Ectoine

Xenobiotics

Chemical

N/A

0.123

0.036

6-Bromotryptophan

Amino acid

Tryptophan metabolism

N/A

−0.758

0.037

1-Linoleoyl-GPA (18:2)

Lipid

Lysophospholipid

HMDB07856

−0.371

0.039

Eicosenoylcarnitine (C20:1)

Lipid

Fatty acid metabolism (acyl carnitine, monounsaturated)

N/A

−0.557

0.039

Erucate (22:1n9)

Lipid

Long-chain monounsaturated fatty acid

HMDB02068

0.346

0.040

Bilirubin

Cofactors and vitamins

Hemoglobin and porphyrin metabolism

HMDB00054

−0.432

0.042

Stearoyl ethanolamide

Lipid

Endocannabinoid

HMDB13078

0.070

0.043

3-Phenylpropionate (hydrocinnamate)

Xenobiotics

Benzoate metabolism

HMDB00764

−0.178

0.043

Beta-hydroxyisovalerate

Amino acid

Leucine, isoleucine, and valine metabolism

HMDB00754

0.723

0.045

Myo-inositol

Lipid

Inositol metabolism

HMDB00211

0.944

0.045

Gulonate

Cofactors and vitamins

Ascorbate and aldarate metabolism

HMDB03290

0.575

0.047

Gluconate

Xenobiotics

Food component/plant

HMDB00625

0.539

0.047

Tryptophan

Amino acid

Tryptophan metabolism

HMDB00929

−1.139

0.048

1-Carboxyethylleucine

Amino acid

Leucine, isoleucine, and valine metabolism

N/A

0.350

0.048

Alpha-ketobutyrate

Amino acid

Methionine, cysteine, SAM, and taurine metabolism

HMDB00005

0.268

0.049

Lanthionine

Amino acid

Methionine, cysteine, SAM, and taurine metabolism

N/A

−0.229

0.049