Cited by 236Tryptophan and brain disordersMicrobial Natural Products and BiosynthesisNeurotransmitter Receptor Influence on Behavior

5-Hydroxytryptophan (5-HTP): Natural Occurrence, Analysis, Biosynthesis, Biotechnology, Physiology and Toxicology

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Maffei, Massimo E.·2020·International Journal of Molecular Sciences

Abstract

L-5-hydroxytryptophan (5-HTP) is both a drug and a natural component of some dietary supplements. 5-HTP is produced from tryptophan by tryptophan hydroxylase (TPH), which is present in two isoforms (TPH1 and TPH2). Decarboxylation of 5-HTP yields serotonin (5-hydroxytryptamine, 5-HT) that is further transformed to melatonin (N-acetyl-5-methoxytryptamine). 5-HTP plays a major role both in neurologic and metabolic diseases and its synthesis from tryptophan represents the limiting step in serotonin and melatonin biosynthesis. In this review, after an look at the main natural sources of 5-HTP, the chemical analysis and synthesis, biosynthesis and microbial production of 5-HTP by molecular engineering will be described. The physiological effects of 5-HTP are discussed in both animal studies and human clinical trials. The physiological role of 5-HTP in the treatment of depression, anxiety, panic, sleep disorders, obesity, myoclonus and serotonin syndrome are also discussed. 5-HTP toxicity and the occurrence of toxic impurities present in tryptophan and 5-HTP preparations are also discussed.

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  1. [190]Kilbourne E.M. Philen R.M. Kamb M.L. Falk H. Tryptophan produced by showa denko and epidemic eosinophilia-myalgia syndrome J. Rheumatol. 1996 23 81 88 8895184

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Authors
Maffei, M. E.
Affiliations
University of Turin (IT)
Corresponding author
Maffei, Massimo E.
Venue
International Journal of Molecular Sciences
Publisher
MDPI AG
Published
2020-12-26
Volume
22
Issue
1
Pages
181
ISSN
1422-0067 (ISSN-L)
OpenAlex
W3116316624
Cited by
236
References
196
Citations by year
2026: 45 · 2025: 58 · 2024: 50 · 2023: 44 · 2022: 28 · 2021: 11
FWCI
1.34
Type
journal article
Language
en
Open access
Locations
  • International Journal of Molecular Sciences (publishedVersion, cc-by)
  • Europe PMC (PubMed Central) (publishedVersion, other-oa)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Institutional Research Information System University of Turin (University of Turin) (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
University of Turin (localgrants2020)
Topics
  • Life Sciences › Neuroscience › Biological Psychiatry › Tryptophan and brain disorders
  • Health Sciences › Medicine › Pharmacology › Microbial Natural Products and Biosynthesis
  • Life Sciences › Neuroscience › Cellular and Molecular Neuroscience › Neurotransmitter Receptor Influence on Behavior
Keywords
5-hydroxytryptophan, tryptophan hydroxylase, serotonin synthesis, melatonin synthesis, tryptophan, dietary supplements, depression, anxiety, sleep disorders, obesity, myoclonus, serotonin syndrome, toxic impurities
MeSH terms
Toxicological Phenomena, Animals, Mental Disorders, Biotechnology, Humans, 5-Hydroxytryptophan, Obesity, Sleep Wake Disorders, Serotonin Syndrome

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