The DOI matches its Crossref record; 132 of the 132 references it cites were found in a registry or an index.
The kynurenine pathway in major depressive disorder, bipolar disorder, and schizophrenia: a meta-analysis of 101 studies
Open accessAbstract
The importance of tryptophan as a precursor for neuroactive compounds has long been acknowledged. The metabolism of tryptophan along the kynurenine pathway and its involvement in mental disorders is an emerging area in psychiatry. We performed a meta-analysis to examine the differences in kynurenine metabolites in major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ). Electronic databases were searched for studies that assessed metabolites involved in the kynurenine pathway (tryptophan, kynurenine, kynurenic acid, quinolinic acid, 3-hydroxykynurenine, and their associate ratios) in people with MDD, SZ, or BD, compared to controls. We computed the difference in metabolite concentrations between people with MDD, BD, or SZ, and controls, presented as Hedges’ g with 95% confidence intervals. A total of 101 studies with 10,912 participants were included. Tryptophan and kynurenine are decreased across MDD, BD, and SZ; kynurenic acid and the kynurenic acid to quinolinic acid ratio are decreased in mood disorders (i.e., MDD and BD), whereas kynurenic acid is not altered in SZ; kynurenic acid to 3-hydroxykynurenine ratio is decreased in MDD but not SZ. Kynurenic acid to kynurenine ratio is decreased in MDD and SZ, and the kynurenine to tryptophan ratio is increased in MDD and SZ. Our results suggest that there is a shift in the tryptophan metabolism from serotonin to the kynurenine pathway, across these psychiatric disorders. In addition, a differential pattern exists between mood disorders and SZ, with a preferential metabolism of kynurenine to the potentially neurotoxic quinolinic acid instead of the neuroprotective kynurenic acid in mood disorders but not in SZ.
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“Alongside the biosynthesis of serotonin, an estimated 90% of tryptophan is metabolized via the kynurenine pathway [6].”
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Cited by
Tryptophan metabolism in health and disease
Xue, C., Li, G., Zheng, Q., Gu, X., Shi, Q., Su, Y., Chu, Q., Yuan, X., Bao, Z., Lu, J., et al. (2023) · Cell Metabolism · doi:10.1016/j.cmet.2023.06.004 · Cited by 961
McGuinness, A. J., Davis, J. A., Dawson, S. L., Loughman, A., Collier, F., O’Hely, M., Simpson, C. A., Green, J., Marx, W., Hair, C., et al. (2022) · Molecular Psychiatry · doi:10.1038/s41380-022-01456-3 · Cited by 502
Self-citationHow inflammation affects the brain in depression: a review of functional and structural MRI studies
Han, K.-M., & Ham, B.-J. (2021) · Journal of Clinical Neurology · doi:10.3988/jcn.2021.17.4.503 · Cited by 187
Peripheral and central kynurenine pathway abnormalities in major depression
Paul, E. R., Schwieler, L., Erhardt, S., Boda, S., Trepci, A., Kämpe, R., Asratian, A., Holm, L., Yngve, A., Dantzer, R., et al. (2022) · Brain, Behavior, and Immunity · doi:10.1016/j.bbi.2022.01.002 · Cited by 134
Tryptophan metabolism: Mechanism-oriented therapy for neurological and psychiatric disorders
Li, D., Yu, S., Long, Y., Shi, A., Deng, J., Ma, Y., Wen, J., Li, X., Liu, S., Zhang, Y., et al. (2022) · Frontiers in Immunology · doi:10.3389/fimmu.2022.985378 · Cited by 129
Metadata
- Authors
- Marx, W., McGuinness, A. J., Rocks, T., Ruusunen, A., Cleminson, J., Walker, A. J., Gomes-da-Costa, S., Lane, M., Sanches, M., Diaz, A. P., Tseng, P.-T., Lin, P.-Y., Berk, M., Clarke, G., O’Neil, A., Jacka, F., Stubbs, B., Carvalho, A. F., Quevedo, J., Soares, J. C., & Fernandes, B. S.
- Venue
- Molecular Psychiatry
- Published
- 2020-11-23
- Volume
- 26
- Issue
- 8
- Pages
- 4158-4178
- ISSN
- 1359-4184 (ISSN-L)
- 1476-5578
- OpenAlex
- W3106920291
- Cited by
- 322
- References
- 132
- FWCI
- 2.05
- Type
- journal article
- Language
- en
- Open access
- green
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- The paper
- Marx, W., McGuinness, A. J., Rocks, T., Ruusunen, A., Cleminson, J., Walker, A. J., Gomes-da-Costa, S., Lane, M., Sanches, M., Diaz, A. P., Tseng, P.-T., Lin, P.-Y., Berk, M., Clarke, G., O’Neil, A., Jacka, F., Stubbs, B., Carvalho, A. F., Quevedo, J., . . . Fernandes, B. S. (2021). The kynurenine pathway in major depressive disorder, bipolar disorder, and schizophrenia: a meta-analysis of 101 studies. Molecular Psychiatry. https://doi.org/10.1038/s41380-020-00951-9
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
