Background: Dysregulation of the kynurenine metabolic pathway has been reported in several neurological conditions. Methods & results: Sensitive and selective LC–MS/MS methods have been validated for six kynurenine pathway metabolites in human cerebrospinal fluid and plasma. For each matrix, we validated three methods – one for the simultaneous determination of kynurenine, kynurenic acid, anthranilic acid and 3-hydroxy-kynurenine (four-analyte assay), one for quinolinic acid and one for tryptophan – using stable-isotopically labeled internal standards. The dynamic range and quantitation limits were based on endogenous concentrations for each analyte. Conclusion: The use of validated methods for kynurenine pathway metabolites in human cerebrospinal fluid and plasma will provide definitive information in neurological diseases.
Keywords:
- 3-hydroxy-kynurenine
- anthranilic acid
- CSF
- human plasma
- Huntington’s disease
- kynurenic acid
- kynurenine
- kynurenine pathway metabolites
- quinolinic acid
- tryptophan
- validation