Table 3. Principal component analysis of CSF and plasma metabolite log transformed levels.
| Metabolite | PC1 | PC2 | PC3 | PC4 | PC5 | PC6 |
|---|---|---|---|---|---|---|
| CSF metabolites | ||||||
| 3-OH-KYN | 0.445 | -0.576 | -0.421 | 0.099 | 0.260 | 0.103 |
| Kynurenine | 0.791 | 0.070 | 0.081 | 0.365 | -0.242 | -0.038 |
| Quinolinic acid | 0.754 | -0.321 | -0.430 | 0.021 | 0.039 | 0.042 |
| Anthranilic acid | 0.666 | 0.349 | -0.147 | -0.143 | -0.391 | -0.248 |
| Kynurenic acid | 0.465 | -0.150 | 0.411 | 0.364 | -0.355 | 0.542 |
| Tryptophan | 0.527 | 0.245 | -0.146 | 0.646 | 0.041 | -0.357 |
| Plasma metabolites | ||||||
| 3-OH-KYN | 0.662 | -0.352 | 0.391 | -0.140 | 0.189 | -0.216 |
| Kynurenine | 0.844 | 0.143 | 0.130 | -0.153 | 0.246 | 0.156 |
| Quinolinic acid | 0.787 | -0.211 | -0.138 | -0.310 | -0.046 | -0.008 |
| Anthranilic acid | 0.594 | 0.367 | -0.131 | -0.462 | -0.294 | 0.124 |
| Kynurenic acid | 0.500 | 0.046 | 0.614 | -0.105 | 0.328 | -0.177 |
| Tryptophan | 0.291 | 0.649 | -0.197 | 0.102 | 0.566 | 0.298 |
Abbreviations: 3-OH-KYN, 3-hydroxykynurenine