Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: CAS:59-00-7 (Xanthurenic acid)
 47 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Eight kynurenic acid analogues were bath-applied to rat hippocampal slices while recording extracellular synaptic field potentials and the potencies of these analogues for inhibition of these responses were compared to that of kynurenic acid. Quinaldic acid, 4-hydroxyquinoline, 4-hydroxypicolinic acid, L-kynurenine and picolinic acid inhibited evoked field potentials, but were at least 15-fold less potent than kynurenic acid in all pathways tested. Xanthurenic acid was inactive in the pathways tested. Quinolinic acid and dipicolinic acid showed signs of agonist activity with IC50's of approx. 400 microM and 2500 microM, respectively. These studies show that the 2-carboxy group and the 4-hydroxy moiety are essential for the antagonist activity exhibited by kynurenate. They also show that the unsubstituted second aromatic ring greatly enhances the affinity of kynurenate for these receptors and that substitution in at least one position on this aromatic ring abolishes activity.
Brain Res 1985 Dec 30
PMID:Structure-function relationships for kynurenic acid analogues at excitatory pathways in the rat hippocampal slice. 408 92

Immune activation is accompanied by induction of indoleamine (2,3)-dioxygenase (IDO), an enzyme which degrades tryptophan, a phenomenon which plays a role in the pathophysiology of major depression and post-natal depression and anxiety states. TRYCATs - tryptophan catabolites along the IDO pathway - such as kynurenine, kynurenic acid, xanthurenic acid, and quinolinic acid, have multiple effects, e.g. apoptotic, anti- versus pro-oxidant, neurotoxic versus neuroprotective, and anxiolytic versus anxiogenic effects. The aim of the present study was to study the immune effects of the above TRYCATS. Toward this end we examined the effects of the above TRYCATs on the LPS + PHA-induced production of interferon-gamma (IFNgamma), interleukin-10 (IL-10), and tumor necrosis factor-alpha (TNFalpha) in 18 normal volunteers. We found that the production of IFNgamma was significantly decreased by all 4 catabolites. Xanthurenic acid and quinolinic acid decreased the production of IL-10. Kynurenine, kynurenic acid, and xanthurenic acid, decreased the IFNgamma/IL-10 production ratio, whereas quinolinic acid increased this ratio. Kynurenic acid significantly reduced the stimulated production of TNFalpha. It is concluded that kynurenine, kynurenic acid, and xanthurenic acid have anti-inflammatory effects trough a reduction of IFNgamma, whereas quinolinic acid has pro-inflammatory effects in particular via significant decreases in IL-10. Following inflammation-induced IDO activation, some TRYCATs, i.e. kynurenine, kynurenic acid, and xanthurenic acid, exert a negative feedback control over IFNgamma production thus downregulating the initial inflammation, whereas an excess of quinolinic acid further aggravates the initial inflammation.
Neuro Endocrinol Lett 2007 Dec
PMID:The immune effects of TRYCATs (tryptophan catabolites along the IDO pathway): relevance for depression - and other conditions characterized by tryptophan depletion induced by inflammation. 1806 23

Xanthurenic acid (XA), formed from 3-hydroxykynurenine (3-HK) in the kynurenine pathway of tryptophan degradation, may modulate glutamatergic neurotransmission by inhibiting the vesicular glutamate transporter and/or activating Group II metabotropic glutamate receptors. Here we examined the molecular and cellular mechanisms by which 3-HK controls the neosynthesis of XA in rat, mouse and human brain, and compared the physiological actions of 3-HK and XA in the rat brain. In tissue homogenates, XA formation from 3-HK was observed in all three species and traced to a major role of kynurenine aminotransferase II (KAT II). Transamination of 3-HK to XA was also demonstrated using human recombinant KAT II. Neosynthesis of XA was significantly increased in the quinolinate-lesioned rat striatum, indicating a non-neuronal localization of the process. Studies using rat cortical slices revealed that newly produced XA is rapidly released into the extracellular compartment, and that XA biosynthesis can be manipulated experimentally in the same way as the production of kynurenic acid from kynurenine (omission of Na+ or glucose, depolarizing conditions, or addition of 2-oxoacids). The synthesis of XA from 3-HK was confirmed in vivo by striatal microdialysis. In slices from the rat hippocampus, both 3-HK and XA reduced the slopes of dentate gyrus field EPSPs. The effect of 3-HK was reduced in the presence of the KAT inhibitor aminooxyacetic acid. Finally, both 3-HK and XA reduced the power of gamma-oscillatory activity recorded from the hippocampal CA3 region. Endogenous XA, newly formed from 3-HK, may therefore play a physiological role in attentional and cognitive processes.
Neuroscience 2017 Dec 26
PMID:Xanthurenic Acid Formation from 3-Hydroxykynurenine in the Mammalian Brain: Neurochemical Characterization and Physiological Effects. 2903 3