Table 4.
Tentative identification of metabolites significantly different between Rs and NRs taking lithium in the placebo arm of the therapy
| Compound | RT (min) | Measured mass (Da) | Mass error (p.p.m.) | Molecular formula | FC (%) in NRs | P value | CV (%) for QCs | Biochemical category | Subcategory | |
|---|---|---|---|---|---|---|---|---|---|---|
| 1a | Octanoylcarnitine | 4.14 | 287.2090 | −2.3 | C15H29NO4 | 65.0 | 0.028 | 8.92 | Fatty acyls | Fatty esters |
| 2a | Decanoylcarnitine | 8.18 | 315.2403 | −2.1 | C17H33NO4 | 66.6 | 0.024 | 7.64 | Fatty acyls | Fatty esters |
| 3 | Dodecanoylcarnitine | 12.10 | 343.2716 | −1.9 | C19H37NO4 | 40.7 | 0.049 | 5.59 | Fatty acyls | Fatty esters |
| N-palmitoyl serine | C19H37NO4 | Fatty acyls | N-acyl amines | |||||||
| 4a | LPC (16:1) | 16.41 | 493.3166 | −0.5 | C24H48NO7P | −34.9 | 0.025 | 8.21 | Glycerophospholipids | Monoacylglycerophosphocholines |
| LPE (19:1) | C24H48NO7P | Glycerophospholipids | Monoacylglycerophosphoethanolamines | |||||||
| 5 | Trp Phe | 1.03 | 351.1588 | 1.4 | C20H21N3O3 | −40.8 | 0.030 | 27.88 | Dipeptide |
Note: For putative identification, all the compounds with a score >80% were first formula matched with the experimental isotopic pattern distribution on Mass Hunter software.
Also found changed in the same direction in the comparison of Rs and NRs in the ketamine arm infusion.
FC, fold change; FC was calculated as follows: (Average [NRs] – Average [Rs])/Average [Rs] × 100).
+/–, increase/decrease in NRs when compared with Rs.
LPC, lysophosphatidylcholine; this entity has been named with the number of carbon of the fatty acid attached to the backbone and the number of unsaturation, for example, LPC (16:1).
KET, ketamine; NR, non-responders; R, responders.