Tryptophan kynurenine

Keywords Schizophrenia Major depression Thl/Th2 balance Pro-inflammatory cytokines NMDA hypothesis Glutamate Serotonin Tryptophan Kynurenine Kynurenic acid HPA axis... 

In schizophrenia and depression, opposite patterns of type-1 - type-2 immune activation seem to be associated wdth differences in the IDO activation and in the tryptophan— kynurenine metabolism resulting in increased production of kynurenic acid... 

Among the active compounds were xanthurenic and 3-hydroxyanthra-nilic acids, whereas tryptophan, kynurenine, and kynurenic, anthranilic, and nicotinic acids were unable to cause deiodination. These findings support, according to the authors, the view that the deiodination of the thyroid hormone may be closely associated with its biological action. 

T3. Tompsett, S. L., The determination in urine of some metabolites of tryptophan-kynurenine, anthraniUc acid and 3-hydroxyanthranilic acid—and reference to the presence of o-aminophenol in urine. CZin. Chim. Acta 4, 411-419 (1959). 

Kohl C, Walch T, Huber R, Kemmler G, Neurauter G, Fuchs D, Solder E, Schrocksnadel H, Spemer-Unterweger B (2005) Measurement of tryptophan, kynurenine and neopterin in women with and without postpartum blues. J Affect Disord 86 135-142. 

Interest then moved to animals. Both isotopic and nutritional experiments showed that the pathway established in microorganisms applied equally to mammals. Thus hydroxyanthranilic acid was converted to nicotinic acid (9, 604), which it could replace as a growth factor (944), whereas there was no similar conversion of anthranilic acid (343). An outstanding series of isotopic experiments, especially by Heidelberger and co-workers, showed that the 8-carbon atom of the tryptophan side chain became the 8-carbon atom of the kynurenine side chain and that the side chain was lost in conversion of kynurenine to nicotinic acid (369, 371, 427). Moreover the carbon in the 3-position of the indole nucleus became the carboxyl carbon of nicotinic acid (370 this experiment proved conclusively the reality of the tryptophan-nicotinic acid conversion) and the indole nitrogen appeared with only slight dilution in kynurenine, kynurenic acid, and xanthurenic acid (759). All these relations are those to be expected for the pathway tryptophan —+ kynurenine —> hydroxykynurenine (or its phosphate) —> hydroxyanthranilic acid (or its phosphate) — nicotinic acid, illustrated in diagrams 17 and 18. 

Fujigaki, S., Saito, K., Takemura, M., Fujii, H., Wada, H., Noma, A., and Seish-ima, M., Species differences in L-tryptophan-kynurenine pathway metabolism Quantification of anthranilic acid and its related enzymes, Arch. Biochem. Biophys., 358, 329, 1998. 

Trisiamylborane, 216 Tris(methylthio)methyllithium, 412 Tris(trimethylsilyl) phosphite, 412-413 Tiis(triphenylsilyl)vanadate, 413-414 Triton, B., 20, 72, 91, 133 2-(p-Tritylphenyl)sulfonylethanol, 414 2-(p-Tritylphenyl)thioethaiiol, 414 Trityl tetrafluoroborate, 414-415 Tropylium bromide, 369 Tryptamine, 358 Tryptophan, 78, 135 Tryptophan-kynurenine conversion, 261-262... 

Tryptophan-kynurenine conversion. Photosensitized oxygenation of (1) followed by work-up under carefully controlled conditions gives (2) in 41% yield, originally believed to be formed from a dioxetane but now considered to arise from 3-hydroperoxyindolcninc (a). 

Quinolobactin, 8-hydroxy-4-methoxy-2-quinoline carboxylic acid, is an alkaloid produced by Pseudomonas fluorescens ATCC17400. The biosynthesis of quinolobactin involves the tryptophan-kynurenine-xanthurenic acid pathway (Figure 6.13). 

Oxenkrug, G.F., 2010. Tryptophan kynurenine metabolism as a common mediator of genetic and environmental impacts in major depressive disorder the serotonin hypothesis revisited 40 years later. Israeli Journal of Psychiatry and Related Sciences. 47 56-63. 

Arginine Glycine, Serine, Tryptophan, Kynurenine (31), Ornithine, Citrulline, Lysine, Threonine (39), Proline, Norvaline, Nor- 0 8 IB... 

Phenylalanine hydroxylase occurs only in mammalian liver (that is, in the rat, guinea-pig, rabbit, d<, chicken, and human) (see also 259). No activity has been observed in (rat) lung, kidney, brain, or muscle. The system is quite speciOc for L-phenylalanine. Tjrro-sine is not formed from n-phenylalanine, nor are the corresponding p-phenols formed from N-acetyl- or N-chloroacetyl-L-phenylalanine, L-phenylalanine ethyl ester, DL-phenylglycine, phenylserine, phenylpyruvic acid, phenylethylamine, benzoic acid, hippuric acid, cinnamic acid, or mandelic acid (768), or from aniline, acetanilide, tryptophan, kynurenine, anthranilic acid, or phenylacetate (557). This specificity is a distinguishing character of the enzyme, which occurs in the same tissue as the nonspecific aromatic hydroxylase described above. 

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