kynurenic acid {90000259}

Shared Reference Notes

• [1.1] [#Infantile Spasm] 
  - kynurenic acid > a metabolite with antiepileptic effects.
• [1.2] [#Alcoholism] [#Quinolinic acid] 
• [1.3] [#Irritable bowel syndrome] [#kynurenine] 
  -IBS > the level of neuroprotective kynurenic acid (KynA) and the ratio of KynA/Kyn were reduced
• [1.4] [#Bifidobacterium infantis] 
  - treatment with B. infantis 35624 resulted in elevated circulating levels of both #Tryptophan and kynurenic acid.
• [1.5] [#kynurenine] 
  - Kyn can be metabolized either to kynurenic acid (KYNA), with neuroprotective properties, or to the neurotoxic components #Quinolinic acid (QA) and #3-hydroxykynurenine (3-HK)
• - KYNA acts as an NMDA receptor antagonist or through the inhibition of the α7 nicotinic #Acetylcholine (α7nACh) receptors.
• [#Bipolar disorder] [#3-hydroxykynurenine, #Quinolinic acid, #kynurenine] - individuals with BD present lower peripheral blood levels of #Tryptophan, Kyn, KYNA, xanthurenic acid (a component derived from 3-HK), KYNA/Kyn and KYNA/QA ratio
• [#Bipolar disorder] - there is an inverse relationship between #Oscillibacter (a genera increased in patients with BD) and the levels of #Tryptophan and KYNA.
• [#Bipolar disorder] - individuals with manic episode showed the greatest reductions in #Tryptophan levels whereas KYNA levels were more notably reduced among individuals in the depressive phase
• [1.6] 
  - Kynurenic acid is a ligand for the orphan protein GPR35 (the chemokine receptor CXCR8), a membrane-located protein that can modulate the activity of several cytokines and chemokines as well as calcium channels. - It is expressed in the intestine, bone marrow, lymphoid tissue, and central nervous system (CNS). Kynurenic acid is the most active endogenous compound identified to date, which is able to activate GPR35
• [1.7] 
  - enhanced cognitive abilities and memory in model animals have been achieved as a result of enhancing #Glutamate levels via limiting hippocampal kynurenic supply.
• [1.8] [#Picolinic acid, #Quinolinic acid] 
  - The #kynurenine pathway, > production of the bioactive compounds quinolinic, picolinic, kynurenic, and #Anthranilic acid
• [1.9] [#Multiple Sclerosis] [#kynurenine] 
  - the small-intestinal microbes in EAE mice enhanced the KYN pathway, resulting in increased KYNA in the SI; - increased KYNA contributed to the accumulation of Th17-inducing GPR35+ Ly6C+ macrophages in the SI of EAE mice before inflammation in the SC; - microbiota-induced Th17 cells were not retained in the intestines and migrated toward the SC to induce EAE.
• [#Short Chain Fatty Acid] - genera #Lactobacillus and #Megasphaera are increased in #Schizophrenia (SZ), as well as alterations in the #Glutamate-#Glutamine-#GABA cycle, serum levels of #Tryptophan, kynurenic acid (KYNA), and short-chain fatty acids (SCFAs).
• [#Schizophrenia] - altered microbiota in psychosis induces lower serum #Tryptophan, higher serum kynurenic acid (KYNA) levels, and changes in gray matter volume in non-medicated psychotic patients
• [1.11] 
  - #kynurenine aminotransferase (KAT) converts #kynurenine into kynurenic acid (KA). - KA is an N-methyl-D-aspartate (NMDA) receptor antagonist and α7 nicotinic acetylcholine receptor and it exhibits immunosuppressive, anti-oxidative, and neuroprotective roles

References Notes