6-MeO-THBC; 5-MeO-TLN; 6-methoxy-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indole; Pinoline; 6-Methoxy-2,3,4,9-tetrahydro-1H-β-carboline; 6-Methoxy-1,2,3,4-tetrahydro-β-carboline; 6-Methoxy-tetrahydronorharman; 6-Methoxy-2,3,4,9-tetrahydro-1H-β-carboline
|Molar mass||202.25 g·mol−1|
|Melting point||216 °C (421 °F; 489 K)|
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
|what is: / ?)(|
Pinoline is a methoxylated tryptoline (5-methoxytryptoline) that is produced in the pineal gland during the metabolism of melatonin. Its IUPAC name is 6-methoxy-1,2,3,4-tetrahydro-β-carboline, usually abbreviated as 6-MeO-THBC, and its more common name is a combination of "pineal beta-carboline". The biological activity of this molecule is of interest as a potential free radical scavenger, also known as an antioxidant, and as a monoamine oxidase A inhibitor.
Protection of cellular membranes
Aluminium toxicity causes an increase in lipid peroxidation, with most damage occurring in the brain. A recent review of studies shows pinoline and melatonin to be effective at reducing the lipid peroxidation. Studies included both human and animal subjects. The studies’ results support that pinoline has antioxidant properties.
Lipopolysaccharide is produced by Gram-negative bacteria and stimulates the production of free radicals which in turn cause lipid peroxidation. A recent study compared the effectiveness of melatonin and other similar compounds on the lipopolysaccharide induced lipid peroxidation. The results showed support for pinoline’s ability to reduce damage from lipid peroxidation. Pinoline was also shown to be more effective than vitamin E at reducing lipopolysaccharide activity in the retina.
Another recent study compared the antioxidant properties of compounds from the tryptophan metabolic pathway in the pineal gland against oxidative damage to the lipids and proteins of synaptosomes. Synaptosomes isolated from rat brains were used in an experiment assessing damage by measuring malondialdehyde, 4-hydroxyalkenal, and carbonyl content in the proteins. Pinoline was shown to be the most powerful antioxidant. These results support the evidence for pinoline’s antioxidant abilities and the potential to protect against oxidative damage.
- Callaway, James C.; Gyntber, Jukka; Poso, Antti; Airaksinen, Mauno M.; Vepsäläinen, Jouko (1994). "The pictet-spengler reaction and biogenic tryptamines: Formation of tetrahydro-β-carbolines at physiologicalpH". Journal of Heterocyclic Chemistry 31 (2): 431. doi:10.1002/jhet.5570310231.
- Schiller, Erich; Bartsch, H. (2003). Free Radicals and Inhalation Pathology: Respiratory System, Mononuclear Phagocyte System, Hypoxia and Reoxygenation, Pneumoconioses, and Other Granulomatoses, Cancer (Google Books, page view). Springer. p. 107. ISBN 978-3-540-00201-7. Retrieved 2009-02-14.
- Airaksinen, M. M., Huang, J. T., Ho, B. T., Taylor, D., and Walker, K. (1978). "The Uptake of 6-Methoxy-1,2,3,4-Tetrahydro-β-carboline and its Effect on 5-Hydroxytryptamine Uptake and Release in Blood Platelets". Acta Pharmacol Toxicol 43 (5): 375–380. doi:10.1111/j.1600-0773.1978.tb02281.x.
- Bartels, S. P. (2006) U.S. Patent No. 20,060,292,202 Washington, DC: U.S.
- Mohammadir, Azadeh; Abdollahi, Mohammad (2011). "A Systematic Review on Oxidant/Antioxidant Imbalance in Aluminium Toxicity". International Journal of Pharmacology 7: 12. doi:10.3923/ijp.2011.12.21.
- Sewerynek, E; Wiktorska, JA; Stuss, M (2011). "6-methoxytryptophol reduces lipopolysaccharide-induced lipid peroxidation in vitro more effectively than melatonin". Journal of physiology and pharmacology : an official journal of the Polish Physiological Society 62 (6): 677–83. PMID 22314571.
- Millán-Plano, Sergio; Piedrafita, Eduardo; Miana-Mena, Francisco J.; Fuentes-Broto, Lorena; Martínez-Ballarín, Enrique; López-Pingarrón, Laura; Sáenz, María A.; García, Joaquín J. (2010). "Melatonin and Structurally-Related Compounds Protect Synaptosomal Membranes from Free Radical Damage". International Journal of Molecular Sciences 11 (1): 312–28. doi:10.3390/ijms11010312. PMC 2821006. PMID 20162018.