Table 4.
Plasma and urinary amino acid metabolome
| Amino acid | Plasma (μM) | Urine (nmol/mg creatinine) | ||||
|---|---|---|---|---|---|---|
| Healthy controls | ASD | P value | Healthy controls | ASD | P value | |
| Ala | 294 ± 71.5 | 330 ± 98.3 | 301 (224–432) | 392 (305–533) | 0.030 | |
| Arg | 39.4 ± 10.3 | 48.4 ± 16.6 | 0.016 | 52.1 ± 17.1 | 64.0 ± 18.0 | 0.014 |
| Asn | 33.2 ± 4.57 | 34.3 ± 10.6 | 92.4 (72.1–132) | 169 (123–236) | 0.0012* | |
| Asp | 35.5 ± 7.37 | 37.0 ± 10.0 | 142 (112–179) | 160 (117–241) | ||
| Cys (total) | 41.7 ± 10.4 | 46.1 ± 15.0 | 25.3 (20.4–35.9) | 28.3 (21.1–43.3) | ||
| Gln | 463 ± 38.6 | 496 ± 61.2 | 0.024 | 529 (452–704) | 741 (609–876) | 0.0048 |
| Glu | 1672 ± 324 | 1999 ± 619 | 0.034 | 373 (254–495) | 475 (367–690) | 0.010 |
| Gly | 272 (187–1061) | 241 (121–515) | 1.12 (1.19–2.78) | 2.58 (1.84–3.45) | 0.019 | |
| His | 68.0 ± 8.51 | 72.8 ± 9.96 | 2.19 ± 0.88 | 2.90 ± 1.21 | 0.027 | |
| IIe | 50.7 ± 15.3 | 51.6 ± 12.4 | 13.0 ± 4.37 | 18.1 ± 6.50 | 0.0059 | |
| Leu | 126 ± 34.4 | 132 ± 25.6 | 43.1 ± 13.6 | 52.0 ± 13.5 | 0.028 | |
| Lys | 132 ± 20.3 | 146 ± 36.7 | 136 (83.3–264) | 171 (117–352) | ||
| Met | 23.1 ± 6.41 | 26.2 ± 5.84 | 17.9 ± 7.98 | 23.1 ± 7.20 | 0.0037 | |
| Phe | 68.9 ± 11.3 | 68.8 ± 16.8 | 101 ± 38.9 | 110 ± 32.9 | ||
| Pro | 195 ± 65.4 | 223 ± 94.7 | 14.5 ± 6.21 | 20.7 ± 5.37 | 0.00073** | |
| Ser | 128 ± 23.5 | 132 ± 18.7 | 461 (413–621) | 677 (519–910) | 0.0021* | |
| Thr | 116 ± 36.0 | 141 ± 46.8 | 0.041 | 216 (170–265) | 283 (221–405) | 0.0039 |
| Trp | 5.22 ± 1.26 | 3.92 ± 2.40 | 0.0055 | 114 ± 73.6 | 164 ± 48.6 | 0.0043 |
| Tyr | 84.4 ± 21.3 | 87.9 ± 26.8 | 204 (133–255) | 240 (173–317) | ||
| Val | 125 ± 31.3 | 120 ± 26.0 | 25.6 ± 9.52 | 34.8 ± 10.9 | 0.00073** | |
Data are Mean ± SD or median (lower–upper quartile); healthy controls, n = 21, and ASD, n = 27. Significance: t test for parametric data and Mann-Whitney U for non-parametric data
*P < 0.05 and **P < 0.01 after Bonferroni correction of 20 applied