|
Catharanthine
Catharanthine is a terpene indole alkaloid produced by the medicinal plant '' Catharanthus roseus'' and '' Tabernaemontana divaricata''. 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. Pharmacology (+)-Catharanthine competitively inhibits α9α10 nAChRs with potencies higher than that at α3β4 and α4β2 nAChRs and directly blocks CaV2.2. Catharanthine alkaloids are non competitive antagonist of muscle type nAChRs 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'') Research, studies are performed with Cell (biology), cells or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in ...'' study, it increased the levels of cAMP by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimerization Of Catharanthine And Vindoline
Catharanthine and vindoline are terpenoid indole alkaloids naturally produced within the Madagascar periwinkle plant (''Catharanthus roseus'') whose dimerization produces the anti-cancer drugs vinblastine and vincristine. The precursor of catharanthine and vindoline is strictosidine, the common precursor of all indole alkaloids. Misra, N., Luthra, R., Singh, K. L., & Kumar, S. (1999). Recent advances in biosynthesis of alkaloids. Comprehensive Natural Products Chemistry, 25–59. https://doi.org/10.1016/b978-0-08-091283-7.00127-2 The localization of catharanthine and vindoline within the plant tissue has been heavily studied in recent years with conflicting results. The dimerization of catharanthine and vindoline to form vinblastine and vincristine is catalyzed by a peroxidase and a reductase, and includes several intermediate compounds.Li, C., Wood, J. C., Vu, A. H., Hamilton, J. P., Rodriguez Lopez, C. E., Payne, R. M., Serna Guerrero, D. A., Gase, K., Yamamoto, K., Vaillan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 stemmadenine and using it as a substrate remain unknown to date. It is thought to be intermediate compound in many different biosynthetic pathways such as in Aspidosperma species. Many alkaloids are proposed to be produced through intermediate stemmadenine. Some of them are: * Catharanthine and Tabersonine in '' Catharanthus roseus'' * Subincanadines D-F in '' Aspidosperma subincanum'' It is also present as product in plant like in '' Tabernaemontana dichotoma'' seeds. Pharmacology It has hypotensive and weak muscle relaxant properties. See also *Secologanin *Strictosidine Strictosidine is a natural chemical compound and is classified as a glucoalkaloid and a vinca alkaloid. It is formed by the Pictet–Spengler condensation reaction of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catharanthus Roseus
''Catharanthus roseus'', commonly known as bright eyes, Cape periwinkle, graveyard plant, Madagascar periwinkle, old maid, pink periwinkle, rose periwinkle, is a perennial species of flowering plant in the family Apocynaceae. It is native and endemic to Madagascar, but is grown elsewhere as an ornamental and medicinal plant, and now has a pantropical distribution. It is a source of the drugs vincristine and vinblastine, used to treat cancer. It was formerly included in the genus ''Vinca'' as ''Vinca rosea''. It has many vernacular names among which are ''arivotaombelona'' or ''rivotambelona'', ''tonga'', ''tongatse'' or ''trongatse'', ''tsimatiririnina'', and ''vonenina''. Taxonomy Two varieties are recognized * ''Catharanthus roseus'' var. ''roseus'' : Synonymy for this variety ::''Catharanthus roseus'' var. ''angustus'' Steenis ex Bakhuizen f. :: ''Catharanthus roseus'' var. ''albus'' G.Don G.Don, Gen. Hist. 4(1): 95. 1837. :: ''Catharanthus roseus'' var. ''occellatus'' G.D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinblastine
Vinblastine, sold under the brand name Velban among others, is a chemotherapy medication, typically used with other medications, to treat a number of types of cancer. This includes Hodgkin's lymphoma, non-small-cell lung cancer, bladder cancer, brain cancer, melanoma, and testicular cancer. It is given by injection into a vein. Most people experience some side effects. Commonly it causes a change in sensation, constipation, weakness, loss of appetite, and headaches. Severe side effects include low blood cell counts and shortness of breath. It should not be given to people who have a current bacterial infection. Use during pregnancy will likely harm the baby. Vinblastine works by blocking cell division. Vinblastine was isolated in 1958. An example of a natural herbal remedy that has since been developed into a conventional medicine, vinblastine was originally obtained from the Madagascar periwinkle. It is on the World Health Organization's List of Essential Medicines. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Natural Products
The ''Journal of Natural Products'' is a monthly peer-reviewed scientific journal covering all aspects of research on the chemistry and/or biochemistry of naturally occurring compounds. It is co-published by the American Society of Pharmacognosy and the American Chemical Society. The editor-in-chief is Philip J. Proteau (Oregon State University). History The journal was established in 1938 as ''Lloydia'', published by the Lloyd Library and Museum, and obtained its present title in 1979. It has been the official journal of the American Society of Pharmacognosy since 1961. Originally a quarterly publication, it became a bimonthly journal in 1975, and has appeared monthly since 1992. The American Society of Pharmacognosy began to co-publish the journal with the American Chemical Society in 1996. In 2008, the journal was hijacked by a low-quality open access journal using the same title. , this counterfeit journal was still active. Abstracting and indexing The journal is abstracted ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 enzyme tabersonine 16-hydroxylase (T16H) to form 16-hydroxytabersonine.St-Pierre and De Luca (1995) A Cytochrome P-450 Monooxygenase Catalyzes the First Step in the Conversion of Tabersonine to Vindoline in Catharanthus roseus. Plant Physiology. 109(1). 131-139 The enzyme leading to its formation is currently unknown. Tabersonine is the first intermediate leading to the formation of vindoline one of the two precursors required for vinblastine biosynthesis. See also * Conopharyngine * Tabernanthine *Vinblastine Vinblastine, sold under the brand name Velban among others, is a chemotherapy medication, typically used with other medications, to treat a number of types of cancer. This includes Hodgkin's lymphoma, non-small-cell lung ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strictosidine
Strictosidine is a natural chemical compound and is classified as a glucoalkaloid and a vinca alkaloid. It is formed by the Pictet–Spengler condensation reaction of tryptamine with secologanin, catalyzed by the enzyme strictosidine synthase. Thousands of strictosidine derivatives are sometimes referred to by the broad phrase of monoterpene indole alkaloids. Strictosidine is an intermediate in the biosynthesis of numerous pharmaceutically valuable metabolites including quinine, camptothecin, ajmalicine, serpentine, vinblastine, vincristine and mitragynine. Biosynthetic pathways help to define the subgroups of strictosidine derivatives. Distribution Strictosidine is found in the following plant families: *Apocynaceae Here especially in Rhazya stricta and Catharanthus roseus. * Loganiaceae *Rubiaceae * Icacinaceae * Nyssaceae * Alangiaceae Recent efforts in metabolic engineering have permitted the synthesis of strictosidine by yeast (''Saccharomyces cerevisiae ''S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conopharyngine
Conopharyngine is the major alkaloid present in the leaves and stem-bark of ''Tabernaemontana pachysiphon'' and ''Tabernaemontana crassa, Conopharyngia durissima''. It is closely related voacangine and coronaridine. Conopharyngine pseudoindoxyl, a derivative of it, is also found in the same plant ''Tabernaemontana pachysiphon''. Pharmacology It possess central nervous system stimulant activity and produces bradycardia and hypotension in cats. It has weak acetylcholinesterase inhibitory activity and significantly increases hexobarbitone induced sleeping time. Toxicity It has low intravenous toxicity in mice (LD50 = 143 mg/kg). See also * Ibogaline References {{Reflist Alkaloids found in Iboga Methoxy compounds Heterocyclic compounds with 5 rings Methyl esters Nitrogen heterocycles Tryptamine alkaloids Catechol ethers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Akuammicine
Akuammicine is a monoterpene indole alkaloid of the Vinca sub-group. It is found in the Apocynaceae family of plants including '' Picralima nitida'', '' Vinca minor'' and the '' Aspidosperma''. History The alkaloids are a large group of natural products which are classified according to the part-structure which members of a particular group contain. Akuammicine is a monoterpene indole alkaloid of the Vinca sub-group which shares a common biosynthesis with other members, namely that they are derived from strictosidine. It was first isolated in 1927 and had been investigated by Sir Robert Robinson and others before its structure was correctly deduced. This was confirmed by X-ray crystallography in 2017. Natural occurrence Akuammicine is found in plants of the Apocynaceae family and was first isolated from '' Picralima nitida''. It has also been reported in '' Catharanthus roseus''. Synthesis Biosynthesis As with other indole alkaloids, the biosynthesis of akuammicine start ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyrylcholinesterase
Butyrylcholinesterase ( HGNC symbol BCHE; EC 3.1.1.8), also known as BChE, BuChE, BuChase, pseudocholinesterase, or plasma (cholin)esterase, is a nonspecific cholinesterase enzyme that hydrolyses many different choline-based esters. In humans, it is made in the liver, found mainly in blood plasma, and encoded by the ''BCHE'' gene. It is very similar to the neuronal acetylcholinesterase, which is also known as RBC or erythrocyte cholinesterase. The term "serum cholinesterase" is generally used in reference to a clinical test that reflects levels of both of these enzymes in the blood. Assay of butyrylcholinesterase activity in plasma can be used as a liver function test as both hypercholinesterasemia and hypocholinesterasemia indicate pathological processes. The half-life of BCHE is approximately 10 to 14 days. Butyrylcholine is a synthetic compound that does not occur in the body naturally. It is used as a tool to distinguish between acetylcholinesterase and butyrylcholinesteras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRPA1
Transient receptor potential cation channel, subfamily A, member 1, also known as transient receptor potential ankyrin 1, TRPA1, or The Mustard and Wasabi Receptor, is a protein that in humans is encoded by the ''TRPA1'' (and in mice and rats by the ''Trpa1'') gene. TRPA1 is an ion channel located on the plasma membrane of many human and animal cells. This ion channel is best known as a sensor for pain, cold and itch in humans and other mammals, as well as a sensor for environmental irritants giving rise to other protective responses (tears, airway resistance, and cough). Function TRPA1 is a member of the transient receptor potential channel family. TRPA1 contains 14 N-terminal ankyrin repeats and is believed to function as a mechanical and chemical stress sensor. One of the specific functions of this protein involves a role in the detection, integration, and initiation of pain signals in the peripheral nervous system. It can be activated at sites of tissue injury or sites ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TRPM8
Transient receptor potential cation channel subfamily M (melastatin) member 8 (TRPM8), also known as the cold and menthol receptor 1 (CMR1), is a protein that in humans is encoded by the ''TRPM8'' gene. The TRPM8 channel is the primary molecular transducer of cold somatosensation in humans. In addition, mints can desensitize a region through the activation of TRPM8 receptors (the 'cold'/menthol receptor). Structure The TRPM8 channel is a homotetramer, composed of four identical subunits with a transmembrane domain with six helices (S1–6). The first four, S1–4, act as the voltage sensor and allow binding of menthol, icilin and similar channel agonists. S5 and S6 and a connecting loop, also part of the structure, make up the pore, a non-selective cation channel which consists of a highly conserved hydrophobic region. A range of diverse components are required for the high level of specificity in response to cold and menthol stimuli which eventually lead to ion flow through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
