Table 1.
List of serum metabolites along with their measured or reported concentrations and their standard deviations and/or ranges (as measured in µM).
| Metabolite | Platform | Concentration | Literature Value |
|---|---|---|---|
|
WATER-SOLUBLE COMPOUNDS
AMINO ACIDS |
|||
| Alanine * | LC–MS/MS and NMR | 240 ± 30 | 151–222 a |
| Arginine | LC–MS/MS and NMR | 218 ± 33 | 135–182 a |
| Asparagine * | LC–MS/MS and NMR | 25 ± 4 | 20–33 b |
| Aspartate * | LC–MS/MS and NMR | 24 ± 11 | 14–16 c, 31–36 a |
| Beta-alanine * | NMR | 8 ± 1 | 8–9 d |
| Citrulline * | LC–MS/MS and NMR | 88 ± 15 | 71–84 d |
| Creatine | LC–MS/MS and NMR | 196 ± 28 | |
| Glutamate * | LC–MS/MS and NMR | 92 ± 19 | 35–39 d, 174–198 a |
| Glutamine * | LC–MS/MS and NMR | 330 ± 42 | 246–260 d |
| Glycine * | LC–MS/MS and NMR | 398 ± 65 | 405–428 d |
| Histidine * | LC–MS/MS | 78 ± 10 | 74–84 c |
| Isoleucine | LC–MS/MS and NMR | 153 ± 14 | 101–122 a |
| Leucine * | LC–MS/MS and NMR | 212 ± 24 | 205–264 c |
| Lysine * | LC–MS/MS and NMR | 88 ± 15 | 58–92 b |
| Methionine * | LC–MS/MS and NMR | 34 ± 4 | 22–29 c, 46–52 a |
| Ornithine * | LC–MS/MS and NMR | 61 ± 13 | 62–135 a |
| Phenylalanine * | LC–MS/MS and NMR | 71 ± 7 | 65–75 c |
| Proline * | LC–MS/MS and NMR | 103 ± 15 | 84–110 a |
| Serine * | LC–MS/MS and NMR | 85 ± 14 | 86–89 d |
| Threonine * | LC–MS/MS and NMR | 74 ± 12 | 58–76 c |
| Tryptophan * | LC–MS/MS | 47 ± 7 | 37–42 c |
| Tyrosine | LC–MS/MS and NMR | 91 ± 10 | 68–75 c |
| Valine * | LC–MS/MS and NMR | 356 ± 34 | 262–322 c |
| BIOGENIC AMINES | |||
| Acetyl-ornithine | LC–MS/MS | 3 ± 1 | |
| Asymmetric-dimethylarginine * | LC–MS/MS | 1.1 ± 0.2 | 1.3–2.1 e |
| Carnosine * | LC–MS/MS | 30 ± 12 | 15–20 d |
| Creatinine * | LC–MS/MS and NMR | 113 ± 17 | 109–140 f |
| Kynurenine * | LC–MS/MS | 7 ± 2 | 4–7 b |
| Methionine-sulfoxide | LC–MS/MS | 1.2 ± 0.3 | |
| Methylhistidine * | LC–MS/MS | 14 ± 2 | 2–12 g |
| Putrescine | LC–MS/MS | 0.04 ± 0.02 | |
| Sarcosine | LC–MS/MS and NMR | 3 ± 1 | 10–12 d |
| Serotonin * | LC–MS/MS | 9 ± 3 | 4–13 h |
| Spermidine | LC–MS/MS | 0.2 ± 0.1 | |
| Spermine | LC–MS/MS | 0.2 ± 0.2 | |
| Taurine | LC–MS/MS and NMR | 80 ± 20 | 33–47 d |
| Total-dimethylarginine | LC–MS/MS | 2.1 ± 0.3 | |
| Trans-hydroxyproline | LC–MS/MS | 25 ± 5 | |
| Trimethylamine N-oxide | LC–MS/MS | 6 ± 3 | |
| CARBOHYDRATES | |||
| Glucose * | LC–MS/MS and NMR | 3962 ± 443 | 3290–4070 i |
| ORGANIC ACIDS | |||
| 3-hydroxybutyrate * | NMR | 340 ± 145 | 250–2110 j |
| Acetate | NMR | 403 ± 199 | 920–1040 k |
| Alpha-aminoadipate | LC–MS/MS | 1.28 ± 0.52 | 7.3–8.1 d |
| Ascorbate (Vitamin C) * | NMR | 11 ± 3 | 8–18 l |
| Formate | NMR | 78 ± 12 | |
| Fumarate | NMR | 1.2 ± 0.2 | |
| Lactate | NMR | 4850 ± 2017 | 658–1600 m |
| Pyruvate | NMR | 150 ± 40 | |
| MISCELANEOUS | |||
| Acetone * | NMR | 70 ± 22 | 80–990 j |
| Betaine | LC–MS/MS and NMR | 169 ± 31 | 14–26 n |
| Choline | LC–MS/MS and NMR | 20 ± 4 | 4–5 n |
| Ethanol * | NMR | 8 ± 1 | 3–68 i |
| Glycerol | NMR | 314 ± 38 | |
| Isopropanol | NMR | 2 ± 1 | |
| Methanol | NMR | 32 ± 4 | |
| Myo-inositol | NMR | 45 ± 11 | |
| Urea | NMR | 1321 ± 282 | 1950–4080 o |
| Uridine | NMR | 3 ± 1 | |
|
LIPID-LIKE COMPOUNDS
PHOSPHATIDYLCHOLINES, ACYL-ALKYL |
|||
| PC ae (36:0) | LC–MS/MS | 1.6 ± 0.4 | |
| PC ae (40:6) | LC–MS/MS | 0.46 ± 0.11 | |
| PHOSPHATIDYLCHOLINES, DIACYL | |||
| PC aa (32:2) | LC–MS/MS | 4 ± 1 | |
| PC aa (36:6) | LC–MS/MS | 0.7 ± 0.2 | |
| PC aa (36:0) | LC–MS/MS | 6 ± 2 | |
| PC aa (38:6) | LC–MS/MS | 1 ± 0.3 | |
| PC aa (38:0) | LC–MS/MS | 0.8 ± 0.2 | |
| PC aa (40:6) | LC–MS/MS | 1.6 ± 0.4 | |
| PC aa (40:2) | LC–MS/MS | 0.4 ± 0.1 | |
| PC aa (40:1) | LC–MS/MS | 0.21 ± 0.04 | |
| LYSOPHOSPHATIDYLCHOLINES, ACYL C | |||
| LysoPC(14:0) | LC–MS/MS | 0.8 ± 0.1 | |
| LysoPC(16:1) | LC–MS/MS | 0.6 ± 0.1 | |
| LysoPC(16:0) * | LC–MS/MS | 20 ± 4 | 15–58 n |
| LysoPC(17:0) | LC–MS/MS | 3 ± 1 | |
| LysoPC(18:2) | LC–MS/MS | 15 ± 3 | 30–186 n |
| LysoPC(18:1) | LC–MS/MS | 6 ± 1 | 18–69 n |
| LysoPC(18:0) * | LC–MS/MS | 30 ± 5 | 14–82 n |
| LysoPC(20:4) | LC–MS/MS | 0.48 ± 0.14 | |
| LysoPC(20:3) | LC–MS/MS | 1.6 ± 0.3 | |
| LysoPC(24:0) | LC–MS/MS | 0.051 ± 0.012 | |
| LysoPC(26:1) | LC–MS/MS | 0.1 ± 0.04 | |
| LysoPC(26:0) | LC–MS/MS | 0.7 ± 0.3 | |
| LysoPC(28:1) | LC–MS/MS | 0.3 ± 0.1 | |
| LysoPC(28:0) | LC–MS/MS | 0.28 ± 0.11 | |
| SPHINGOMYELINS | |||
| SM(16:1) | LC–MS/MS | 5 ± 1 | |
| SM(16:0) | LC–MS/MS | 68 ± 10 | |
| SM(18:1) | LC–MS/MS | 11 ± 3 | |
| SM(18:0) | LC–MS/MS | 12 ± 2 | |
| SM(20:2) | LC–MS/MS | 1.1 ± 0.3 | |
| HYDROXYSPHINGOMYELINS | |||
| SM(14:1(OH)) | LC–MS/MS | 5 ± 1 | |
| SM(16:1(OH)) | LC–MS/MS | 9 ± 2 | |
| SM(22:2(OH)) | LC–MS/MS | 4 ± 1 | |
| SM(22:1(OH)) | LC–MS/MS | 9 ± 1 | |
| SM(24:1(OH)) | LC–MS/MS | 2 ± 0.4 | |
| ACYLCARNITINES | |||
| C0 (Carnitine) | LC–MS/MS | 7 ± 1 | |
| C2 (Acetylcarnitine) * | LC–MS/MS | 2 ± 1 | 0.65–1.09 b |
| C3:1 (Propenoylcarnitine) | LC–MS/MS | 0.029 ± 0.004 | |
| C3 (Propionylcarnitine) | LC–MS/MS | 0.2 ± 0.04 | |
| C4:1 (Butenylcarnitine) | LC–MS/MS | 0.017 ± 0.002 | |
| C4 (Butyrylcarnitine) | LC–MS/MS | 0.2 ± 0.1 | |
| C3-OH (Hydroxypropionylcarnitine) * | LC–MS/MS | 0.027 ± 0.004 | 0.01–0.02 b |
| C5:1 (Tiglylcarnitine) | LC–MS/MS | 0.023 ± 0.004 | |
| C5 (Valerylcarnitine) * | LC–MS/MS | 0.09 ± 0.03 | 0.03–0.06 b |
| C4-OH (C3-DC) (Hydroxybutyrylcarnitine) | LC–MS/MS | 0.04 ± 0.01 | |
| C6:1 (Hexenoylcarnitine) | LC–MS/MS | 0.02 ± 0.01 | |
| C6 (C4:1-DC) (Hexanoylcarnitine) | LC–MS/MS | 0.05 ± 0.01 | 0.02–0.03 b |
| C5-OH (C3-DC-M) (hydroxyvalerylcarnitine) * | LC–MS/MS | 0.04 ± 0.01 | 0.05–0.06 b |
| C5:1-DC (Glutaconylcarnitine) | LC–MS/MS | 0.018 ± 0.003 | |
| C5-DC (C6-OH)(Glutarylcarnitine) | LC–MS/MS | 0.03 ± 0.01 | |
| C8 (Octanoylcarnitine) | LC–MS/MS | 0.02 ± 0.01 | |
| C5-M-DC (methylglutarylcarnitine) | LC–MS/MS | 0.0196 ± 0.0024 | |
| C9 (Nonaylcarnitine) | LC–MS/MS | 0.022 ± 0.003 | |
| C7-DC (Pimelylcarnitine) * | LC–MS/MS | 0.04 ± 0.04 | 0.01–0.02 b |
| C10:2 (Decadienylcarnitine) | LC–MS/MS | 0.06 ± 0.01 | |
| C10:1 (Decenoylcarnitine) | LC–MS/MS | 0.17 ± 0.03 | |
| C10 (Decanoylcarnitine) | LC–MS/MS | 0.18 ± 0.04 | |
| C12:1 (Dodecenoylcarnitine) | LC–MS/MS | 0.084 ± 0.014 | |
| C12 (Dodecanoylcarnitine) * | LC–MS/MS | 0.04 ± 0.01 | 0.02–0.03 b |
| C14:2 (Tetradecadienylcarnitine) | LC–MS/MS | 0.03 ± 0.01 | |
| C14:1 (Tetradecenoylcarnitine) | LC–MS/MS | 0.0518 ± 0.0103 | |
| C14 (Tetradecanoylcarnitine) * | LC–MS/MS | 0.02 ± 0.01 | 0.01–0.02 b |
| C12-DC (Dodecanedioylcarnitine) | LC–MS/MS | 0.018 ± 0.003 | |
| C14:2-OH (Hydroxytetradecadienylcarnitine) | LC–MS/MS | 0.008 ± 0.002 | |
| C14:1-OH (Hydroxytetradecenoylcarnitine) | LC–MS/MS | 0.009 ± 0.002 | |
| C16:2 (Hexadecadienylcarnitine) | LC–MS/MS | 0.012 ± 0.002 | |
| C16:1 (Hexadecenoylcarnitine) | LC–MS/MS | 0.029 ± 0.003 | |
| C16 (Hexadecanoylcarnitine) | LC–MS/MS | 0.02 ± 0.01 | |
| C16:2-OH (Hydroxyhexadecadienylcarnitine) | LC–MS/MS | 0.005 ± 0.001 | |
| C16:1-OH (Hydroxyhexadecenoylcarnitine) | LC–MS/MS | 0.0184 ± 0.0034 | |
| C16-OH (Hydroxyhexadecanoylcarnitine) * | LC–MS/MS | 0.008 ± 0.001 | 0.003–0.006 b |
| C18:2 (Octadecadienylcarnitine) | LC–MS/MS | 0.007 ± 0.001 | |
| C18:1 (Octadecenoylcarnitine) | LC–MS/MS | 0.0147 ± 0.0031 | |
| C18 (Octadecanoylcarnitine) | LC–MS/MS | 0.021 ± 0.008 | |
| C18:1-OH (Hydroxyoctadecenoylcarnitine) * | LC–MS/MS | 0.009 ± 0.001 | 0.008–0.009 b |
| TRACE ELEMENTAL COMPOUNDS | |||
| Sodium * | ICP–MS | 133,515 ± 13,658 | 107,400–108,600 p, 136,000–136,710 q |
| Magnesium * | ICP–MS | 931 ± 88 | 850–920 f |
| Phosphorus * | ICP–MS | 1298 ± 164 | 1350–1620 p |
| Potassium * | ICP–MS | 4296 ± 388 | 4060–4340 f |
| Calcium * | ICP–MS | 2228 ± 221 | 1400–2200 h |
| Iron * | ICP–MS | 52 ± 13 | 50–51 r |
| Copper * | ICP–MS | 9 ± 2 | 6–9 r |
| Zinc * | ICP–MS | 12 ± 2 | 14–18 r |
| Selenium * | ICP–MS | 1.4 ± 0.2 | 0.5–2.7 s |
| Rubidium | ICP–MS | 1.8 ± 0.2 | |
| Strontium | ICP–MS | 1 ± 0.1 | |
| Cesium | ICP–MS | 0.0017 ± 0.0003 | |
| Barium | ICP–MS | 0.2 ± 0.03 | |
* Compounds that exhibited good agreement with literature values; a Motyl and Barej, 1986 [40]; b Sadri et al., 2017 [41]; c Greenwood et al., 2001 [42]; d Zhou et al., 2016 [37]; e Chan et al., 2000 [43]; f Consolo et al., 2018 [44]; g van der Drift et al., 2012 [45]; h Hernandez-Castellano et al., 2017 [46]; I Raun and Kristensen, 2011 [33]; j Sato, 2009 [34]; k Sato et al., 1999 [35]; l Padilla et al., 2006 [47]; m Kenny et al., 2002 [48]; n Artegoitia et al., 2014 [49]; o Liker et al., 2005 [50]; p Nozad et al., 2012 [51]; q Macdonald et al., 2017 [52]; r Noaman et al., 2012 [30]; s Waldner et al., 1998 [53].