Â Lapin of Russia has implicated kynurenine in anxiety (1, 2). This has been supported in the US by Oxenkrug, who is of Russian descent (3). Ref. 3 is a free full text article available on the Internet at Pubmed Central. Ref. 3 is on a high academic level, so knowledge of medical matters is important to reading this brilliant article. The layman would struggle with it. Oxenkrug is a brilliant authority on psychiatry, as is Lapin.
Â Kynurenine is the main metabolite of tryptophan, which is found in the diet. Tryptophan is in proteins such as beef, dairy products, etc.
Â Down syndrome, which is a form of developmental disability, has been found to have abnormal tryptophan metabolism (5). This shows the tremendous importance of proper tryptophan metabolism. It also suggests that some tryptophan metabolites might be toxic in excess. Since Down syndrome is a brain disease, it appears to show that the brain is vulnerable to increased kynurenine. There is no known effective treatment for Down syndrome,Â but one study found benefit from vitamins. The government decided not to fund any further studies on this because the study didn't come out the way they wanted it to come out. Pauling blasted the government for this.Â
1.Â Lapin IP. Kynurenines and anxiety. Adv Exp Med Biol. 1996;398:191-194. [PubMed]
Baraldi S, Hepgul N, Mondelli V, Pariante CM.
J Clin Psychopharmacol. 2012 Jun 19. [Epub ahead of print]
8. <cite>Sandyk R. L-tryptophan in neuropsychiatric disorders: a review. Int J Neurosci</cite>Medline
<cite>9. Young SN. The use of diet and dietary components in the study of factors controlling affect in humans: a review. J Psychiatry Neurosci 1993; 18: 235-44.</cite> Medline
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