Abstract
A deficit in brain serotonin (5-hydroxytryptamine; 5-HT) is implicated in a number of psychiatric illnesses, including depression. The treatment efficacy of this highly prevalent brain disorder is not adequate largely due to the depletion of serotonin stores. Tryptophan, an essential amino acid, is the sole precursor of serotonin; its systemic or oral administration increases serotonin synthesis because tryptophan hydroxylase, the rate-limiting enzyme of 5-HT biosynthesis, is physiologically unsaturated with its substrate. The present article targets the importance of tryptophan supplementation in treating serotonin deficiency and improving therapeutic intervention for depression and other serotonin deficiency brain disorders.
Keywords: Tryptophan, serotonin, depression, tryptophan hydroxylase, antidepressants, biosynthesis.
Graphical Abstract
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