The Tryptophan Kynurenine Pathway (TKP) in Post-Covid Syndrome (PCS) (WP5549)

Homo sapiens

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Following the SARS-CoV-2 pandemic, increasing evidence suggests that the overactivation of the Tryptophan–Kynurenine Pathway (TKP) plays a significant role in the pathophysiology of Post-Covid syndrome. This dysregulation is marked by reduced tryptophan (TRP) levels and elevated concentrations of specific tryptophan catabolites (TRYCATs). Notably, heightened TKP activity has been observed in patients exhibiting symptoms of post-acute sequelae of COVID-19 (PASC). In fact, elevated levels of TKP metabolites such as quinolinic acid, 3- hydroxy anthranilic acid and kynurenine, have been associated with cognitive impairments. Persistent inflammatory conditions observed in Post-Covid patients potentially upregulate the indoleamine 2,3-dioxygenase (IDO) enzymes, specifically IDO 1, as well as KMO, which catalyses the conversion from Kynurenine to 3-Hydroxykynurenine. Thus, the kynurenine pathway relates to PACS and potentially enables future biomarker and therapeutic possibilities.

Authors

Kristof-Kirps

Activity

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Organisms

Homo sapiens

Communities

Annotations

Pathway Ontology

kynurenine metabolic pathway tryptophan metabolic pathway immune system disease pathway nervous system disease pathway

Disease Ontology

long COVID mild cognitive impairment

Participants
Query Drugst.One

Label Type Compact URI Comment
Anthranilic acid Metabolite chebi:30754
Kynurenine Metabolite chebi:28683
N-Formylkynurenine Metabolite chebi:30249
3-Hydroxykynurenine Metabolite chebi:1547
3-Hydroxyanthranilic acid Metabolite hmdb:HMDB01476
Xanthurenic acid Metabolite hmdb:HMDB00881
Tryptophan Metabolite chebi:27897 OCR lexicon match: Trp
3-Hydroxykynurenamine Metabolite hmdb:HMDB0060281 3-Hydroxykynurenamine
Quinolinic acid Metabolite hmdb:HMDB00232
Kynurenic Acid Metabolite chebi:18344
H2O2 Metabolite chebi:16240
DDC GeneProduct hgnc.symbol:DDC catalyzes the decarboxylation of aromatic L-amino acids to their amine derivative
AADC (Aromatic L-amino acid decarboxylase)
IDO2 GeneProduct hgnc.symbol:IDO2
TNF GeneProduct hgnc.symbol:TNF
AADAT GeneProduct hgnc.symbol:AADAT KYAT2 = AADAT
Type your comment here
KMO GeneProduct hgnc.symbol:KMO
IL1B GeneProduct hgnc.symbol:IL1B
IFNB1 GeneProduct ensembl:ENSG00000171855
IL6 GeneProduct hgnc.symbol:IL6
AFMID GeneProduct hgnc.symbol:AFMID
HAAO GeneProduct hgnc.symbol:HAAO
IDO1 GeneProduct ncbigene:3620 OCR lexicon match: IDO
TDO2 GeneProduct ncbigene:6999 OCR lexicon match: TDO
KYNU GeneProduct hgnc.symbol:KYNU
KYNU GeneProduct ncbigene:8942
IFNG GeneProduct hgnc.symbol:IFNG
IFNA6 GeneProduct ensembl:ENSG00000120235
KYAT1 Protein uniprot:Q16773 KAT I/glutamine transaminase K/cysteine conjugate beta-lyase 1
KYAT2 Protein uniprot:Q8N5Z0 KAT II/aminoadipate aminotransferase
KYAT3 Protein uniprot:Q6YP21 KAT III/cysteine conjugate beta-lyase 2
KYAT4 Protein uniprot:P00505 KAT IV/glutamic-oxaloacetic transaminase 2/mitochondrial aspartate aminotransferase

References

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