Fig. 1

Summary of TRYCAT pathway in COVID-19. BMI body mass index, C cohort, T2DM type 2 diabetes mellitus, IFN-γ interferon-Gamma, IL-6 interleukin 6, IL-1β interleukin-1 beta, O&NS oxidative and nitrosative stress, O2 oxygen, CCTA chest computed tomography abnormalities, AhR aryl hydrocarbon receptor, IDO indoleamine 2,3 dioxygenase, TDO tryptophan 2,3-dioxygenase, KAT kynurenine aminotransferase, KMO kynurenine 3-monooxygenase, KYNU kynureninase, TRP tryptophan, KYN kynurenine, KA kynurenic acid, 3HK 3-hydroxykynurenine, AA anthranilic acid, XA xanthurenic acid, 3HA 3-hydroxyanthranilic acid, PA picolinic acid, QA quinolinic acid, NAD +  nicotinamide adenine dinucleotide. Created with BioRender.com