Background
Methods
Chest CT measurements
Plasma metabolomics measurements
Statistical analyses
Results
N = 928 | |
---|---|
Age, mean ± SD | 67.5 ± 8.6 |
Male | 466 (50.2) |
Self-reported race | |
White | 850 (91.6) |
Black | 78 (8.4) |
Former Smoker | 688 (74.1) |
Pack Years, mean ± SD | 44.5 ± 24.3 |
Body Mass Index (kg/m2), mean ± SD | 29.0 ± 6.1 |
Inhaled corticosteroid use | 49 (5.3) |
Post Bronchodilator FEV1 (L), mean ± SD | 2.0 ± 0.9 |
Post Bronchodilator FEV1 (percent predicted), mean ± SD | 77.8 ± 26.0 |
Post Bronchodilator FVC (L), mean ± SD | 3.1 ± 1.0 |
Post Bronchodilator FVC (percent predicted), mean ± SD | 86.6 ± 18.5 |
GOLD class | |
PRISm (reduced FEV1 and FVC, with a FEV1-to-FVC ratio of ≥ 0.7) | 82 (8.8) |
GOLD 0 | 412 (44.4) |
GOLD 1 | 97 (10.5) |
GOLD 2 | 198 (21.4) |
GOLD 3 | 109 (11.8) |
GOLD 4 | 29 (3.1) |
Percentage of Lung Occupied by QIA, mean ± SD | 5.0 ± 4.3 |
≥ 5% Percentage of Lung Occupied by QIA | 332 (35.8) |
Percentage of Lung Occupied by Emphysema, mean ± SD | 8.1 ± 16.0 |
≥ 5% Percentage of Lung Occupied by Emphysema | 242 (26.1) |
Association of metabolomics with QIA
Metabolite | HMDB ID* | Percent QIA per unit metabolite, mean [CI]† | FDR p-value | Metabolon class |
---|---|---|---|---|
Positively-associated with QIA | ||||
N-acetylneuraminate | 0000230 | 1.41 [0.80 to 2.02] | < 0.001 | Carbohydrate; Aminosugar Metabolism |
Pseudouridine | 0000767 | 1.35 [0.61 to 2.09] | 0.009 | Nucleotide; Pyrimidine Metabolism, Uracil containing |
C-glycosyltryptophan | 0240296 | 1.31 [0.69 to 1.93] | 0.002 | Amino Acid; Tryptophan Metabolism |
Erythronate | 0000613 | 1.23 [0.59 to 1.87] | 0.005 | Carbohydrate; Aminosugar Metabolism |
N-acetylserine | 0002931 | 1.23 [0.55 to 1.90] | 0.001 | Amino Acid; Glycine, Serine and Threonine Metabolism |
N-acetyl-L-methionine | 0011745 | 1.14 [0.57 to 1.72] | 0.004 | Amino Acid; Methionine, Cysteine, SAM and Taurine Metabolism |
5–6-Dihydrouridine | 0000497 | 1.11 [0.46 to 1.76] | 0.015 | Nucleotide; Pyrimidine Metabolism, Uracil containing |
N-acetylthreonine | 0062557 | 1.01 [0.40 to 1.62] | 0.021 | Amino Acid; Glycine, Serine and Threonine Metabolism |
N2, N2-Dimethylguanosine | 0004824 | 1.01 [0.35 to 1.66] | 0.030 | Nucleotide; Purine Metabolism, Guanine containing |
Cytidine | 0000089 | 0.98 [0.48 to 1.48] | 0.004 | Nucleotide; Pyrimidine Metabolism, Cytidine containing |
Hydroxyasparagine | 0341329 | 0.98 [0.32 to 1.64] | 0.038 | Amino Acid; Alanine and Aspartate Metabolism |
Sphingosine | 0000252 | 0.94 [0.40 to 1.47] | 0.013 | Lipid; Sphingosines |
N-Acetylgalactosamine, N-Acetyl-D-glucosamine‡ | 0000212, 000021‡ | 0.92 [0.37 to 1.47] | 0.018 | Carbohydrate; Aminosugar Metabolism |
N4-Acetylcytidine | 0005923 | 0.89 [0.49 to 1.30] | 0.001 | Nucleotide; Pyrimidine Metabolism, Cytidine containing |
N-Acetylputrescine | 0002064 | 0.89 [0.30 to 1.49] | 0.035 | Amino Acid; Polyamine Metabolism |
N-acetyl-isoputreanine | 0.87 [0.44 to 1.29] | 0.003 | Amino Acid; Polyamine Metabolism | |
Succinylcarnitine | 0061717 | 0.85 [0.37 to 1.32] | 0.012 | Energy; TCA Cycle |
1-Methyl-4-imidazoleacetate | 0002820 | 0.81 [0.35 to 1.28] | 0.013 | Amino Acid; Histidine Metabolism |
3-ureido-Propionate | 0000026 | 0.78 [0.43 to 1.14] | 0.001 | Nucleotide; Pyrimidine Metabolism, Uracil containing |
Quinolinate | 0000232 | 0.73 [0.37 to 1.08] | 0.003 | Cofactors and Vitamins; Nicotinate and Nicotinamide Metabolism |
Acisoga | 0061384 | 0.66 [0.29 to 1.02] | 0.011 | Amino Acid; Polyamine Metabolism |
5-(galactosylhydroxy)-L-lysine | 0.61 [0.23 to 0.98] | 0.025 | Amino Acid; Lysine Metabolism | |
N-acetyltaurine | 0240253 | 0.55 [0.16 to 0.94] | 0.048 | Amino Acid; Methionine, Cysteine, SAM and Taurine Metabolism |
Phenylacetylglutamine | 0006344 | 0.54 [0.23 to 0.85] | 0.015 | Peptide; Acetylated Peptides |
1-Carboxyethyltyrosine | 0.51 [0.22 to 0.81] | 0.015 | Amino Acid; Tyrosine Metabolism | |
Negatively-associated with QIA | ||||
Phosphatidylcholine (18:0/18:2) | 0008039 | − 2.09 [− 3.26 to − 0.91] | 0.013 | Lipid; Phosphatidylcholine (PC) |
Phosphatidylcholine (16:0/18:2) | 0007973 | − 1.92 [− 3.25 to − 0.59] | 0.044 | Lipid; Phosphatidylcholine (PC) |
Lysophosphatidylcholine (16:0/0:0) | 0010382 | − 1.71 [− 2.76 to − 0.66] | 0.024 | Lipid; Lysophospholipid |
Phosphatidylcholine (18:2/20:4) | 0008147 | − 1.59 [− 2.21 to − 0.97] | < 0.001 | Lipid; Phosphatidylcholine (PC) |
Phosphatidylcholine (16:0/18:0) | 0007970 | − 1.45 [− 2.31 to − 0.59] | 0.018 | Lipid; Phosphatidylcholine (PC) |
Lysophosphatidylcholine (18:0/0:0) | 0010384 | − 1.45 [− 2.19 to − 0.70] | 0.005 | Lipid; Lysophospholipid |
Sphingomyelin (D18:1/20:0) | 0012102 | − 1.40 [− 2.22 to − 0.57] | 0.017 | Lipid; Sphingomyelins |
Vitamin A | 0000305 | − 1.16 [− 1.74 to − 0.57] | 0.004 | Cofactors and Vitamins; Vitamin A Metabolism |
Sphingomyelin (D18:2(4E,14Z)/14:0), Sphingomyelin (D18:1/14:1(9Z))‡ | 0240637, 0240612‡ | − 1.15 [− 1.63 to − 0.66] | < 0.001 | Lipid; Sphingomyelins |
Thyroxine | 0000248 | − 1.13 [− 1.83 to − 0.42] | 0.025 | Amino Acid; Tyrosine Metabolism |
L-alpha-Aminobutyric acid | 0000452 | − 1.13 [− 1.69 to − 0.57] | 0.003 | Amino Acid; Glutathione Metabolism |
Phosphatidylinositol (18:0/20:4) | 0009815 | − 1.10 [− 1.80 to − 0.39] | 0.028 | Lipid; Phosphatidylinositol (PI) |
Lysophosphatidylcholine (0:0/16:0) | 0061702 | − 1.10 [− 1.68 to − 0.53] | 0.005 | Lipid; Lysophospholipid |
3-methyl-2-oxobutyrate | 0000019 | − 1.06 [− 1.75 to − 0.37] | 0.030 | Amino Acid; Leucine, Isoleucine and Valine Metabolism |
Gamma-glutamyl-2-aminobutyrate | − 1.06 [− 1.48 to − 0.64] | < 0.001 | Peptide; Gamma-glutamyl Amino Acid | |
Lysophosphatidylcholine (18:1/0:0) | 0002815 | − 1.04 [− 1.69 to − 0.39] | 0.025 | Lipid; Lysophospholipid |
Lysophosphatidylcholine (18:2/0:0) | 0010386 | − 1.04 [− 1.69 to − 0.39] | 0.025 | Lipid; Lysophospholipid |
Sphingomyelin (D17:2/16:0) Sphingomyelin (D18:2/15:0)‡ | 0240677 | − 1.02 [− 1.47 to − 0.58] | < 0.001 | Lipid; Sphingomyelins |
Arachidoylcarnitine | 0006460 | − 1.00 [− 1.52 to − 0.48] | 0.005 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Long Chain Saturated) |
Phosphatidylcholine (18:2/18:2) | 0008138 | − 0.98 [− 1.53 to − 0.44] | 0.010 | Lipid; Phosphatidylcholine (PC) |
Sphingomyelin (D17:1/14:0), Sphingomyelin (D16:1/15:0)‡ | − 0.95 [− 1.33 to − 0.57] | < 0.001 | Lipid; Sphingomyelins | |
Ceramide (D18:2/22:0) | − 0.93 [− 1.38 to − 0.47] | 0.003 | Lipid; Ceramides | |
Citrulline | 0000904 | − 0.92 [− 1.56 to − 0.29] | 0.043 | Amino Acid; Urea cycle; Arginine and Proline Metabolism |
Ceramide (D20:1/18:0), Ceramide (D16:1/22:0), Ceramide (D18:1/20:0)‡ | 0240684, 0240682, 0004951‡ | − 0.91 [− 1.40 to − 0.41] | 0.009 | Lipid; Ceramides |
Lysophosphatidylcholine (24:0/0:0) | 0010405 | − 0.84 [− 1.25 to − 0.43] | 0.003 | Lipid; Lysophospholipid |
Pathway* | Total in pathway | Hits | FDR p-value | Pathway impact value | |
---|---|---|---|---|---|
Nicotinate and nicotinamide metabolism | 15 | 1 | Quinolinate | 6.81E−11 | 0 |
Histidine metabolism | 16 | 1 | Methylimidazoleacetic acid | 5.61E−09 | 0 |
Starch and sucrose metabolism | 18 | 2 | Sucrose; Maltose | 2.14E−07 | 0.123 |
Glycerophospholipid metabolism | 36 | 2 | Phosphatidylcholine (PC); 1-Acyl-sn-glycero-3-phosphocholine (Lysophosphatidylcholine, LPC) | 7.83E−0 | 0.112 |
Pyrimidine metabolism | 39 | 2 | 3-Ureidopropionate; Cytidine | 1.81E−05 | 0.020 |
Galactose metabolism | 27 | 1 | Sucrose | 1.50E−04 | 0.039 |
Pentose and glucuronate interconversions | 18 | 1 | D-Xylose | 2.11E−04 | 0.078 |
Arginine and proline metabolism | 38 | 1 | N-Acetylputrescine | 2.77E−04 | 0.023 |
Pantothenate and CoA biosynthesis | 19 | 2 | 3-Ureidopropionate; 3-Methyl-2-oxobutanoic acid | 4.05E−04 | 0.029 |
Sphingolipid metabolism | 21 | 2 | Sphingomyelin; Sphingosine | 4.60E−04 | 0.045 |
beta-Alanine metabolism | 21 | 1 | 3-Ureidopropionate | 6.93E−04 | 0.104 |
Arachidonic acid metabolism | 36 | 1 | Phosphatidylcholine (PC) | 8.32E−04 | 0 |
Linoleic acid metabolism | 5 | 1 | Phosphatidylcholine (PC) | 8.32E−04 | 0 |
Primary bile acid biosynthesis | 46 | 1 | Taurochenodeoxycholate | 0.009 | 0.010 |
Valine, leucine and isoleucine degradation | 40 | 1 | 3-Methyl-2-oxobutanoic acid | 0.02 | 0.011 |
Cysteine and methionine metabolism | 33 | 2 | (S)-2-Aminobutanoate; 2-Oxobutanoate | 0.02 | 0.102 |
Valine, leucine and isoleucine biosynthesis | 8 | 2 | 3-Methyl-2-oxobutanoic acid; 2-Oxobutanoate | 0.07 | 0 |
Arginine biosynthesis | 14 | 1 | Citrulline | 0.10 | 0.228 |
Propanoate metabolism | 23 | 1 | 2-Oxobutanoate | 0.10 | 0.041 |
Glycine, serine and threonine metabolism | 33 | 1 | 2-Oxobutanoate | 0.10 | 0 |
Tyrosine metabolism | 42 | 1 | Thyroxine | 0.12 | 0 |
alpha-Linolenic acid metabolism | 13 | 2 | Phosphatidylcholine (PC); Stearidonic acid | 0.19 | 0 |
Biosynthesis of unsaturated fatty acids | 36 | 3 | Octadecanoic acid; Docosahexaenoic acid; Icosapentaenoic acid | 0.27 | 0 |
Fatty acid biosynthesis | 47 | 1 | Tetradecanoic acid | 0.36 | 0 |
Multinomial outcomes of CT phenotypes
Metabolite | HMDB ID* | Odds of QIA-predominant over emphysema-predominant, mean [CI]† | FDR p-value | Metabolon class |
---|---|---|---|---|
Symmetric dimethylarginine (SMDA), Asymmetric dimethylarginine (ADMA)‡ | 0003334, 0001539‡ | 5.19 [2.01–13.40] | 0.021 | Amino Acid; Urea cycle; Arginine and Proline Metabolism |
Phenylalanine | 0000159 | 5.04 [1.73–14.72] | 0.040 | Amino Acid; Phenylalanine Metabolism |
Asparagine | 0000168 | 4.79 [1.99–11.54] | 0.018 | Amino Acid; Alanine and Aspartate Metabolism |
Sulfate | 01448 | 4.05 [1.79–9.17] | 0.022 | Xenobiotics; Chemical |
Proline | 0000162, 0003411 | 3.36 [1.61–7.03] | 0.028 | Amino Acid; Urea cycle; Arginine and Proline Metabolism |
Kynurenine | 0000684 | 2.82 [1.48–5.34] | 0.031 | Amino Acid; Tryptophan Metabolism |
Erythronate | 0000613 | 2.71 [1.46–5.04] | 0.031 | Carbohydrate; Aminosugar Metabolism |
N-acetyl-isoputreanine | 2.64 [1.73–4.04] | 0.002 | Amino Acid; Polyamine Metabolism | |
Alpha-Ketoglutaramate | 0001552 | 2.57 [1.46–4.50] | 0.026 | Amino Acid; Glutamate Metabolism |
Gamma-Glutamylphenylalanine | 0000594 | 2.49 [1.40–4.42] | 0.031 | Peptide; Gamma-glutamyl Amino Acid |
Phosphatidylethanolamine (16:0/18:2) | 0005322 | 2.37 [1.65–3.40] | < 0.001 | Lipid; Phosphatidylethanolamine (PE) |
Phosphatidylethanolamine (16:0/18:1) | 0005320 | 2.31 [1.66–3.23] | < 0.001 | Lipid; Phosphatidylethanolamine (PE) |
Aspartate | 0000191 | 2.25 [1.40–3.61] | 0.022 | Amino Acid; Alanine and Aspartate Metabolism |
Lysophosphatidylethanolamine (16:0/0:0) | 0011503 | 2.16 [1.30–3.58] | 0.039 | Lipid; Lysophospholipid |
Phosphatidylethanolamine (18:0/20:4) | 0009003 | 2.10 [1.39–3.18] | 0.018 | Lipid; Phosphatidylethanolamine (PE) |
Phosphatidylethanolamine (16:0/20:4) | 0005323 | 2.09 [1.43–3.04] | 0.011 | Lipid; Phosphatidylethanolamine (PE) |
3-Ureidopropionate | 0000026 | 1.99 [1.40–2.83] | 0.011 | Nucleotide; Pyrimidine Metabolism, Uracil containing |
N-formylanthranilic acid | 0004089 | 1.97 [1.32–2.95] | 0.026 | Amino Acid; Tryptophan Metabolism |
Phosphatidylethanolamine (18:0/18:2) | 0008994 | 1.94 [1.37–2.74] | 0.011 | Lipid; Phosphatidylethanolamine (PE) |
Succinylcarnitine | 0061717 | 1.92 [1.22–3.01] | 0.049 | Energy; TCA Cycle |
Quinolinate | 0000232 | 1.89 [1.35–2.66] | 0.011 | Cofactors and Vitamins; Nicotinate and Nicotinamide Metabolism |
Gulonate | 0003290 | 1.89 [1.25–2.87] | 0.037 | Cofactors and Vitamins; Ascorbate and Aldarate Metabolism |
Methionine sulfone | 0062174 | 1.85 [1.26–2.70] | 0.031 | Amino Acid; Methionine, Cysteine, SAM and Taurine Metabolism |
1-Carboxyethylphenylalanine | 1.81 [1.34–2.43] | 0.011 | Amino Acid; Phenylalanine Metabolism | |
Glutamate | 0000148 | 1.80 [1.25–2.61] | 0.031 | Amino Acid; Glutamate Metabolism |
Sphingomyelin (D18:1/20:1(11Z)), Sphingomyelin (D18:2/20:0)‡ | 0240610, 0240632‡ | 0.31 [0.16–0.63] | 0.026 | Lipid; Sphingomyelins |
Thyroxine | 0000248 | 0.32 [0.16–0.64] | 0.028 | Amino Acid; Tyrosine Metabolism |
Sphingomyelin (D18:1/18:1), Sphingomyelin (D18:2/18:0)‡ | 0012101 | 0.32 [0.16–0.66] | 0.031 | Lipid; Sphingomyelins |
Sphingomyelin (D18:1/18:0) | 0001348 | 0.33 [0.16–0.68] | 0.038 | Lipid; Sphingomyelins |
Citrulline | 0000904 | 0.41 [0.22–0.74] | 0.043 | Amino Acid; Urea cycle; Arginine and Proline Metabolism |
Sphingomyelin (D18:2/18:1) | 0.43 [0.26–0.69] | 0.020 | Lipid; Sphingomyelins | |
Eicosenoylcarnitine | 0.47 [0.31–0.70] | 0.011 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) | |
Oleoylcarnitine | 0005065 | 0.49 [0.30–0.80] | 0.049 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) |
Stearoylethanolamide | 0013078 | 0.50 [0.31–0.80] | 0.045 | Lipid; Endocannabinoid |
Glycerol | 0000131 | 0.53 [0.38–0.74] | 0.011 | Lipid; Glycerolipid Metabolism |
N6,N6,N6-Trimethyl-L-lysine | 0001325 | 0.55 [0.38–0.81] | 0.033 | Amino Acid; Lysine Metabolism |
Homostachydrine | 0033433 | 0.59 [0.43–0.81] | 0.024 | Xenobiotics; Food Component/Plant |
9-Decenoylcarnitine | 0013205 | 0.61 [0.44–0.84] | 0.037 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) |
9-Hexadecenoylcarnitine | 0013207 | 0.62 [0.45–0.86] | 0.049 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) |
10-undecylenate | 0033724 | 0.63 [0.47–0.85] | 0.037 | Lipid; Medium Chain Fatty Acid |
Myristoleoylcarnitine | 0240588 | 0.63 [0.49–0.82] | 0.018 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) |
Trans-2-Dodecenoylcarnitine | 13,326 | 0.64 [0.49–0.84] | 0.031 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Monounsaturated) |
Dodecadienoate | 0.66 [0.52–0.85] | 0.028 | Lipid; Fatty Acid, Dicarboxylate | |
Decanoylcarnitine | 0000651 | 0.67 [0.52–0.87] | 0.034 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Medium Chain) |
Octanoylcarnitine | 0000791 | 0.68 [0.53–0.88] | 0.037 | Lipid; Fatty Acid Metabolism (Acyl Carnitine, Medium Chain) |
Linoelaidic acid, Linoleic acid‡ | 0006270, 0000673‡ | 0.69 [0.54–0.87] | 0.033 | Lipid; Long Chain Polyunsaturated Fatty Acid (n3 and n6) |
gamma-Linolenic acid, alpha-Linolenic acid‡ | 0003073, 0001388‡ | 0.71 [0.57–0.88] | 0.031 | Lipid; Long Chain Polyunsaturated Fatty Acid (n3 and n6) |
Vaccenic acid, Elaidic acid, cis-Vaccenic acid, Oleic acid‡ | 0003231, 0000573, 0240219, 0000207‡ | 0.71 [0.56–0.90] | 0.049 | Lipid; Long Chain Monounsaturated Fatty Acid |
10Z-Heptadecenoic acid | 0060038 | 0.74 [0.61–0.90] | 0.041 | Lipid; Long Chain Monounsaturated Fatty Acid |
7Z,10Z-Hexadecadienoic acid | 0000477 | 0.74 [0.61–0.89] | 0.031 | Lipid; Long Chain Polyunsaturated Fatty Acid (n3 and n6) |
Pathway* | Total in pathway | Hits | FDR p-value | Pathway impact value | |
---|---|---|---|---|---|
Nicotinate and nicotinamide metabolism | 15 | 2 | Aspartate; Quinolinate | 2.71E−05 | 0 |
Aminoacyl-tRNA biosynthesis | 48 | 5 | Asparagine; Phenylalanine; Aspartate; Proline; Glutamate | 2.71E−05 | 0 |
Arginine and proline metabolism | 38 | 2 | Proline; Glutamate | 2.71E−05 | 0.164 |
Alanine, aspartate and glutamate metabolism | 28 | 4 | Aspartate; Asparagine; Glutamate; 2-Oxoglutaramate | 2.71E−05 | 0.421 |
Arginine biosynthesis | 14 | 3 | Glutamate; Citrulline; Aspartate | 2.71E−05 | 0.345 |
Pentose and glucuronate interconversions | 18 | 2 | Gulonate; D-Xylose | 2.71E−05 | 0.156 |
D-Glutamine and D-glutamate metabolism | 6 | 1 | Glutamate | 2.71E−05 | 0.500 |
Glutathione metabolism | 28 | 1 | Glutamate | 2.71E−05 | 0.020 |
Glyoxylate and dicarboxylate metabolism | 32 | 1 | Glutamate | 2.71E−05 | 0 |
Butanoate metabolism | 15 | 1 | Glutamate | 2.71E−05 | 0 |
Porphyrin and chlorophyll metabolism | 30 | 1 | Glutamate | 2.71E−05 | 0 |
Nitrogen metabolism | 6 | 1 | Glutamate | 2.71E−05 | 0 |
Histidine metabolism | 16 | 2 | Glutamate; Aspartate | 2.79E−05 | 0 |
Glycerophospholipid metabolism | 36 | 1 | Phosphatidylethanolamine | 3.91E−05 | 0.104 |
Glycosylphosphatidylinositol (GPI)-anchor biosynthesis | 14 | 1 | Phosphatidylethanolamine | 3.91E−05 | 0.004 |
Sulfur metabolism | 8 | 1 | Sulfate | 5.60E−05 | 0.213 |
Purine metabolism | 65 | 1 | Sulfate | 5.60E−05 | 0 |
beta-Alanine metabolism | 21 | 2 | Aspartate; 3-Ureidopropionate | 1.09E−04 | 0.104 |
Pantothenate and CoA biosynthesis | 19 | 2 | Aspartate; 3-Ureidopropionate | 1.09E−04 | 0.029 |
Phenylalanine, tyrosine and tryptophan biosynthesis | 4 | 1 | Phenylalanine | 1.99E−04 | 0.500 |
Phenylalanine metabolism | 10 | 1 | Phenylalanine | 1.99E−04 | 0.357 |
Pyrimidine metabolism | 39 | 2 | Orotidine 5'-phosphate; 3-Ureidopropionate | 5.06E−04 | 0.083 |
Amino sugar and nucleotide sugar metabolism | 37 | 1 | beta-D-Fructose | 0.002 | 0 |
Ascorbate and aldarate metabolism | 8 | 1 | Gulonate | 0.002 | 0 |
Tryptophan metabolism | 41 | 2 | Kynurenine; Formylanthranilate | 0.004 | 0.099 |
Lysine degradation | 25 | 1 | N6,N6,N6-Trimethyl-L-lysine | 0.007 | 0 |
Caffeine metabolism | 10 | 1 | 7-Methylxanthine | 0.01 | 0 |
Primary bile acid biosynthesis | 46 | 1 | Glycocholate | 0.01 | 0.008 |
Tyrosine metabolism | 42 | 1 | Thyroxine | 0.04 | 0 |
Glycerolipid metabolism | 16 | 1 | Glycerol | 0.50 | 0.237 |
Galactose metabolism | 27 | 1 | Glycerol | 0.50 | 0 |
Sphingolipid metabolism | 21 | 1 | Sphingomyelin | 0.85 | 0 |