Catharanthine is a terpene indole alkaloid produced by the medicinal plant ''
Catharanthus roseus'' and ''
Tabernaemontana divaricata
''Tabernaemontana divaricata'', commonly called pinwheel flower, crape jasmine, East India rosebay, and Nero's crown, is an evergreen shrub or small tree native to South Asia, Southeast Asia and China. In zones where it is not hardy it is grown a ...
''. Catharanthine is derived from
strictosidine, but the exact mechanism by which this happens is currently unknown. Catharanthine is one of the two precursors that form
vinblastine, the other being
vindoline
Vindoline is a chemical precursor to vinblastine.
Vindoline is formed through biosynthesis from Tabersonine
Tabersonine is a terpene indole alkaloid found in the medicinal plant ''Catharanthus roseus'' and also in the genus Voacanga (both taxa b ...
.
Pharmacology
(+)-Catharanthine competitively inhibits α9α10
nAChRs
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral n ...
with potencies higher than that at
α3β4 and
α4β2
The alpha-4 beta-2 nicotinic receptor, also known as the α4β2 receptor, is a type of nicotinic acetylcholine receptor implicated in learning, consisting of α4 and β2 subunits. It is located in the brain, where activation yields post- and pre ...
nAChRs and directly blocks
CaV2.2.
Catharanthine alkaloids are non competitive antagonist of muscle type
nAChRs
Nicotinic acetylcholine receptors, or nAChRs, are receptor polypeptides that respond to the neurotransmitter acetylcholine. Nicotinic receptors also respond to drugs such as the agonist nicotine. They are found in the central and peripheral n ...
and this is thought to be the case due to presence of catharanthine moiety in those compounds.
In ''
in vitro
''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...
'' study, it increased the levels of
cAMP
Camp may refer to:
Outdoor accommodation and recreation
* Campsite or campground, a recreational outdoor sleeping and eating site
* a temporary settlement for nomads
* Camp, a term used in New England, Northern Ontario and New Brunswick to descri ...
by inhibiting cAMP phosphodiesterase in brain. It is a potent inhibitor of TRPM8, similar to BCTC.
Structural analysis of catharanthine shows activity on
TRPM8,
TRPA1
Transient receptor potential cation channel, subfamily A, member 1, also known as transient receptor potential ankyrin 1, TRPA1, or The Wasabi Receptor, is a protein that in humans is encoded by the ''TRPA1'' (and in mice and rats by the ''Trpa1' ...
, and
butyrylcholinesterase.
See also
*
Akuammicine
*
Conopharyngine
Conopharyngine is the major alkaloid present in the leaves and stem-bark of ''Tabernaemontana pachysiphon'' and '' Conopharyngia durissima''. It is closely related voacangine and coronaridine. Conopharyngine pseudoindoxyl, a derivative of it, is ...
*
Stemmadenine
Stemmadenine is a terpene indole alkaloid. Stemmadenine is believed to be formed from preakuammicine by a carbon-carbon bond cleavage. Cleavage of a second carbon-carbon bond is thought to form dehydrosecodine. The enzymes forming stemmadeni ...
*
Tabersonine
Tabersonine is a terpene indole alkaloid found in the medicinal plant ''Catharanthus roseus'' and also in the genus Voacanga (both taxa belonging to the alkaloid-rich family Apocynaceae). Tabersonine is hydroxylated at the 16 position by the enzy ...
References
External links
* {{cite journal , pmid = 23532933 , year = 2013 , last1 = Jadhav , first1 = A. , last2 = Liang , first2 = W. , last3 = Papageorgiou , first3 = P. C. , last4 = Shoker , first4 = A. , last5 = Kanthan , first5 = S. C. , last6 = Balsevich , first6 = J. , last7 = Levy , first7 = A. S. , last8 = Heximer , first8 = S. , last9 = Backx , first9 = P. H. , last10 = Gopalakrishnan , first10 = V. , title = Catharanthine dilates small mesenteric arteries and decreases heart rate and cardiac contractility by inhibition of voltage-operated calcium channels on vascular smooth muscle cells and cardiomyocytes , journal = The Journal of Pharmacology and Experimental Therapeutics , volume = 345 , issue = 3 , pages = 383–392 , doi = 10.1124/jpet.112.199661 , s2cid = 206501362
Alkaloids