Monoamine precursors are precursors of monoamines and monoamine neurotransmitters in the body.[1][2] The amino acids L-tryptophan and L-5-hydroxytryptophan (5-HTP; oxitriptan) are precursors of serotonin and melatonin, while the amino acids L-phenylalanine, L-tyrosine, and L-DOPA (levodopa) are precursors of dopamine, epinephrine (adrenaline), and norepinephrine (noradrenaline).[1][2]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/c1/L-Tryptophan_-_L-Tryptophan.svg/225px-L-Tryptophan_-_L-Tryptophan.svg.png)
Administration of monoamine precursors can increase the levels of monoamine neurotransmitters in the body and brain.[2] Monoamine precursors may be used in combination with peripherally selective aromatic L-amino acid decarboxylase inhibitors (AAAD inhibitors; also known as DOPA decarboxylase (DDC) inhibitors) such as carbidopa and benserazide to restrict metabolism and activation in the periphery.[3] Carbidopa/levodopa and levodopa/benserazide are used to increase brain dopamine levels in the treatment of Parkinson's disease.[3] Carbidopa/oxitriptan (EVX-101), which increases brain serotonin levels, is under development as an antidepressant for possible use in the treatment of depression.[4][5]
Droxidopa (L-DOPS) is a synthetic precursor or prodrug of norepinephrine used orally in the treatment of certain types of hypotension and other conditions.[6][7] Dipivefrine is a synthetic precursor or prodrug of epinephrine used as an ophthalmic medication.[7]
References
edit- ^ a b Kohlstadt, Ingrid (19 April 2016). Food and Nutrients in Disease Management. CRC Press. ISBN 9781420067637.
- ^ a b c Fernandes, John; Saudubray, Jean-Marie; Berghe, Georges van den; Walter, John H. (22 November 2006). Inborn Metabolic Diseases: Diagnosis and Treatment. Springer. ISBN 9783540287858.
- ^ a b Salat D, Tolosa E (January 2013). "Levodopa in the treatment of Parkinson's disease: current status and new developments". J Parkinsons Dis. 3 (3): 255–69. doi:10.3233/JPD-130186. PMID 23948989.
- ^ Turner EH, Loftis JM, Blackwell AD (March 2006). "Serotonin a la carte: supplementation with the serotonin precursor 5-hydroxytryptophan". Pharmacol Ther. 109 (3): 325–338. doi:10.1016/j.pharmthera.2005.06.004. PMID 16023217.
- ^ "Carbidopa/Oxytriptan - Evecxia - AdisInsight".
- ^ Goldstein DS (2006). "L-Dihydroxyphenylserine (L-DOPS): a norepinephrine prodrug". Cardiovasc Drug Rev. 24 (3–4): 189–203. doi:10.1111/j.1527-3466.2006.00189.x. PMID 17214596.
- ^ a b Scott KA, Cox PB, Njardarson JT (May 2022). "Phenols in Pharmaceuticals: Analysis of a Recurring Motif". J Med Chem. 65 (10): 7044–7072. doi:10.1021/acs.jmedchem.2c00223. PMID 35533692.