// Workers AI · dad joke modeWhat did Shepherdine say to her sheep? "Baa-d hair day?
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| Names | |
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| IUPAC names
1-methyl-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-6-ol | |
| Other names
1-Methyl-6-hydroxy-1,2,3,4-tetrahydrobetacarboline; 1-Methyl-6-hydroxytryptoline; 1-Methyl-6-hydroxytetrahydrocarboline; 5-Hydroxymethyltryptoline; 5-Hydroxymettryptoline; 6-Hydroxy-1-methyltryptoline; 6-OH-Mthbc; 6-Hydroxytetrahydroharman; 6-Hydroxy-1,2,3,4-tetrahydroharmane; 6-Tetrahydroharmol | |
| Identifiers | |
3D model (JSmol) |
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PubChem CID |
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| Properties | |
| C12H14N2O | |
| Molar mass | 202.257 g·mol−1 |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Shepherdine, also known as 6-hydroxy-1-tetrahydrocarboline (or 6-Hydroxy-1-methyltryptoline; 6-OH-Mthbc) it is an alkaloid found naturally in mammals and in small amounts in some fruits and fruit juices;[1] it has been reported to be present in bananas, pineapples, and tomatoes. It is said that shepherdine—specifically its oxidized metabolites, which are similar to certain salsolinols—increases in the brains of mammals following alcohol consumption, as a consequence of chronic alcoholism.
Shepherdine is known by many names in the literature; it has been referred to as 5-hydroxymettryptoline, 6-hydroxymettryptoline, or 7-hydroxy-1-methyltetrahydro-beta-carboline, although, despite the confusion, all these names describe the same compound
Formation
[edit]Shepherdine is formed as a result of the oxidation of alcohol, which produces acetaldehyde and free radicals in the cytoplasm of serotonergic axon terminals; these conditions facilitate the endogenous synthesis of shepherdine through the reaction of acetaldehyde with 5-hydroxytryptamine, as well as for the oxygen-radical-mediated oxidation of this alkaloid. The main product of shepherdine oxidation by the hydroxyl radical in the presence of reduced glutathione is 8-S-glutathionyl-1-methyl-1,2,3,4-tetrahydro-beta-carboline-5,6-dione, which exhibits neurotoxic properties; specifically, it is a monoaminergic neurotoxin with toxicity approximately equal to that of 6-hydroxydopamine when administered to the brain (the LD50 value for the oxidized metabolite of shepherdine is 2.9 μg), it causes episodes of hyperactivity and tremors; it binds to the GABAB receptor and induces increased release and turnover of several neurotransmitters; it is hypothesized that it may act as a reverse agonist of the GABAB receptor. The metabolite promotes increased release of several specific neurotransmitters, including dopamine and endogenous opioids, in brain regions innervated by serotonergic terminals.[2][3]
Natural occurrence
[edit]In mammals
[edit]There are several studies that have determined the levels of shepherdine in tissues and biological fluids; for example, a 1983 study on rats detected it in urine and feces, and the compound was found in the liver, kidneys, and plasma; however, that study reported the absence of the compound in the brain;[4] a 2009 study, also conducted on rats, determined its concentration in the brains of newborn rats, noting that shepherdine levels increased when the rats were exposed to alcohol.[5] Research conducted in the 1980s also described the natural presence of shepherdine in animals;[6][7][8][9] it was detected as a component of human and feline urine. It was concluded that shepherdine is naturally present in mammalian urine and is most likely a metabolite of 1-methyltryptoline.[6][10]
In plants
[edit]Shepherdine has been found in bananas, pineapples, and tomatoes, as well as in their juices.[1] It was first described as an alkaloid specifically from the plant Shepherdia canadensis[11]
See also
[edit]References
[edit]- 1 2 Herraiz, Tomas; Galisteo, Juan (2003-11-19). "Tetrahydro-β-carboline Alkaloids Occur in Fruits and Fruit Juices. Activity as Antioxidants and Radical Scavengers". Journal of Agricultural and Food Chemistry. 51 (24): 7156–7161. doi:10.1021/jf030324h. ISSN 0021-8561. PMID 14611187.
- ↑ Wrona, M. Z.; Waskiewicz, J.; Han, Q. P.; Han, J.; Li, H.; Dryhurst, G. (1997). "Putative oxidative metabolites of 1-methyl-6-hydroxy-1,2,3,4-tetrahydro-beta-carboline of potential relevance to the addictive and neurodegenerative consequences of ethanol abuse". Alcohol. 14 (3). Fayetteville, N.Y.: 213–223. doi:10.1016/s0741-8329(96)00144-9. ISSN 0741-8329. PMID 9160798.
- ↑ Han, Q. P.; Dryhurst, G. (1996-03-29). "Influence of glutathione on the oxidation of 1-methyl-6-hydroxy-1,2,3,4-tetrahydro-beta-carboline: chemistry of potential relevance to the addictive and neurodegenerative consequences of ethanol use". Journal of Medicinal Chemistry. 39 (7): 1494–1508. doi:10.1021/jm9504870. ISSN 0022-2623. PMID 8691480.
- ↑ Beck, O.; Lundman, A. (1983-05-01). "Occurrence of 6-hydroxy-1-methyl-1,2,3,4-tetrahydro-beta-carboline in tissues and body fluids of rat". Biochemical Pharmacology. 32 (9): 1507–1510. doi:10.1016/0006-2952(83)90473-2. ISSN 0006-2952. PMID 6860369.
- ↑ Mao, Jian; Su, Yang; Luan, Yujing; Chen, Xuechai; Deng, Yulin (2009). "[Determination of 6-hydroxy-1-methyl-1,2,3,4-tetrahydro-beta-carboline, 5-hydroxytryptamine and 5-hydroxyindole acetic acid in the neonatal rat brains using high performance iquid chromatography-electrochemical detection]". Se Pu = Chinese Journal of Chromatography. 27 (2): 216–219. ISSN 1000-8713. PMID 19626852.
- 1 2 Beck, O.; Repke, D. B.; Faull, K. F. (1986). "6-Hydroxymethtryptoline is naturally occurring in mammalian urine: identification by combined chiral capillary gas chromatography and high resolution mass spectrometry". Biomedical & Environmental Mass Spectrometry. 13 (9): 469–472. doi:10.1002/bms.1200130903. ISSN 0887-6134. PMID 2946335.
- ↑ Beck, O.; Faull, K. F. (1986-08-01). "Concentrations of the enantiomers of 5-hydroxymethtryptoline in mammalian urine: implications for in vivo biosynthesis". Biochemical Pharmacology. 35 (15): 2636–2639. doi:10.1016/0006-2952(86)90067-5. ISSN 0006-2952. PMID 3741463.
- ↑ Peura, P.; Johnson, J. V.; Yost, R. A.; Faull, K. F. (1989). "Concentrations of tryptoline and methtryptoline in rat brain". Journal of Neurochemistry. 52 (3): 847–852. doi:10.1111/j.1471-4159.1989.tb02531.x. ISSN 0022-3042. PMID 2918311.
- ↑ Beck, O.; Faull, K. F.; Barchas, J. D. (1985). "Chiral analysis of urinary 5-hydroxymethtryptoline: implications for endogenous biosynthesis and formation during ethanol intoxication". Progress in Clinical and Biological Research. 183: 145–160. ISSN 0361-7742. PMID 4048181.
- ↑ Beck, O.; Faull, K. F.; Repke, D. B. (1986). "Rapid hydroxylation of methtryptoline (1-methyltetrahydro-beta-carboline) in rat: identification of metabolites by chiral gas chromatography-mass spectrometry". Naunyn-Schmiedeberg's Archives of Pharmacology. 333 (3): 307–312. doi:10.1007/BF00512946. ISSN 0028-1298. PMID 3762741.
- ↑ Ayer, W. A.; Browne, L. M. (1970). "Alkaloids of Shepherdiaargentea and Shepherdiacanadensis". Canadian Journal of Chemistry. 48 (13). NRC Research Press: 1980–1984. doi:10.1139/v70-328. ISSN 0008-4042.