Colchicum autumnale alkaloids

In addition, the alkaloid colchicine (from Colchicum autumnale) blocks tubulin polymerization by binding to heterodimeric (3-tubulin between amino acids 239 and 254. Since it inhibits the MT-dependent migration of granulocytes into areas of inflammation and their MT-dependent release of proinflammatory agents, it is used to treat attacks of gout. Its antimitotic effect in the gastrointestinal system induces diarrhoea. Nocodazole competes for the binding site of colchicine and has similar effects on heterodimeric (3-tubulin. 

Several groups of drugs that bind to tubulin at different sites interfere with its polymerization into microtubules. These drugs are of experimental and clinical importance (Bershadsky and Vasiliev, 1988). For example, colchicine, an alkaloid derived from the meadow saffron plant Colchicum autumnale or Colchicum speciosum), is the oldest and most widely studied of these drugs. It forms a molecular complex with tubulin in the cytosol pool and prevents its polymerization into microtubules. Other substances such as colcemid, podophyllotoxin, and noco-dazole bind to the tubulin molecule at the same site as colchicine and produce a similar effect, albeit with some kinetic differences. Mature ciliary microtubules are resistant to colchicine, whereas those of the mitotic spindle are very sensitive. Colchicine and colcemid block cell division in metaphase and are widely used in cytogenetic studies of cultured cells to enhance the yield of metaphase plate chromosomes. 

Colchicine is an alkaloid of Colchicum autumnale. Colchicine can produce dramatic relief from acute gout. Its mechanism of action is based on disappearance of microtubules in granulocytes, thereby inhibiting their migratory capacity, which is brought forward by the ability of colchicine to bind to tubulin. Colchicine is rapidly absorbed after oral administration and then metabolized to several metabolites which are excreted in the bile. Elimination from the body is slow. 

Although NSAIDs are now the first-line drugs for acute gout, colchicine was the primary treatment for many years. Colchicine is an alkaloid isolated from the autumn crocus, Colchicum autumnale. Its structure is shown in Figure 36-6. 

Colchicine is a poisonous tricyclic tropane alkaloid from the autumn crocus (Colchicum autumnale) and gloriosa lily (Gloriosa superba). This alkaloid is a potent spindle fiber poison, preventing tubulin polymerization.25 Colchicine has been used as an effective anti-inflammatory drug in the treatment of gout and chronic myelocytic leukemia, but therapeutic effects are attainable at toxic or near toxic dosages. For this reason, colchicine and its analogs are primarily used as biochemical tools in the mechanistic study of new mitotic inhibitors. 

Colchicine is an alkaloid isolated from the autumn crocus, Colchicum autumnale. Its structure is shown in Figure 36-6. 

The chemistry and pharmacology of colchicine, the major alkaloid from Colchicum autumnale, have been repeatedly reviewed (/), and findings made since 1984 have been reported (2a-d). Recent developments in the... 

Colchicum autumnale 17). With the isolation of monophenol androbiphe-nyline (13) and the diphenol colchibiphenyline (14) from Colchicum ritchii from southern Jordan (72), two more representatives of this group of alkaloids became available. 

Compared with extracts, pure compounds undoubtedly guarantee a more precise and reproducible dosage and are the only acceptable form of administration of active principles characterised by an extremely narrow therapeutic window, such as the plant alkaloid colchicine 40 from Colchicum autumnale L. Lethal poisoning from colchicine has been reported upon ingestion of 3-4 times the therapeutic dose of this compound111 and it would, therefore, be impractical to use colchicine-rich extracts rather than their active principle. 

An alkaloid obtained from the corm and seeds of the meadow saffron, Colchicum autumnale (Liliaceae) and other Colchicum species. 

The alkaloid colchicine (FI) isolated from the medicinal plant Colchicum autumnale L. (Liliaceae family) still is used to treat gout and familial Mediterranean fever. FI and thiocolchicine (F2) (SCH3 rather than OCH3 at C-10), which is more stable and more potent but slightly more toxic, are mitotic inhibitors that inhibit polymerization of tubulin (69). Although they show antileukemic activity, they are too toxic to use as anticancer agents, which prompts the synthesis of new, less toxic analogs. 

Colchicum autumnale (autumn crocus) and other Colchicum species belong to the family known as the Colchicaceae, a proposed subdivision of the Liliaceae. They contain colchicine and related alkaloids. Other members of the Colchicaceae include Gloriosa species and Merendera species. C. autumnale (autumn crocus) is the traditional source of colchicine, which is covered in a separate monograph. 

LOIC C Colchicum and demecolchicine Colchicine is an alkaloid, previously extracted from the seeds of the Autumn Crocus or Meadow-saffron, Colchicum autumnale L., but nowadays from the seeds of Gloriosa,... 

Major alkaloid extracted from seeds of Colchicum autumnale common meadow saffron. Nausea, vomiting, convulsions, paralysis, death. Used as a treatment for gout and in experimental biology as an arrestor of mitosis to facilitate examination of chromosomes. 

Also mentioned in the aforecited book are colchicine and colchidnamide, derived from the common autumn crocus (Colchicum autumnale), also called meadow saffron. (Colchicine, incidentally, is used in plant gaieties to artificially produce mutations.) The notable use cited is against breast cancer, but gout and arthritis also yield to treatment. It is emphasized that both these alkaloids are potent, and their use requires expert medical supervision. Another plant mentioned is cro-talaria (Crotalaria spectabilis), from which a toxic alkaloid called monocrotaline may be obtained. This substance also has antitumor properties, but acts against the liver. 

Colchicine occurs as the major alkaloid of the autumn crocus, Colchicum autumnale and the African climbing Lily, GloriosasuperbaLinn., (Family Liliaceae). 

Colchicine is present in the poisonous autumn crocus (meadow saffron). It is the major alkaloid of Colchicum autumnale L. and Lili-aceae. It was used in poison potions in the ancient kingdom of Colchis (Greece). It is used therapeutically as an antineoplast, for the suppression of gout, and in the treatment of Mediterranean fever. It is nsed in plant studies for doubling chromosome groups. 

Saffron genus Colchicum (Colchicum L.) produces colchicines. Metacolchicine is in Sandersonia aurantiaca and other colchicines in meadow saffron (Colchicum autumnale L.). Stereoidal alkaloids in the Liliaceae family are found in the Hellebore genus (Veratrum Bemch.). Jervine, cyclo-pamine (Figure 1.18), cycloposine, protoveratrine A, and protoveratrine B yield Veratrum album. Veramadines A and B are reported to be found in Veratratum mackii var. japonicum. O-Acetyljervine has been reported in the false hellebore (Veratrum lobelianum Bemch.). Steroidal alkaloids... 

At the end of the 1930s, with the alkaloid colchicine [303] from the autumn crocus (Colchicum autumnale, also known as the meadow safifon or naked lady) the first natural product was discovered, which attacks the spindle apparatus. Whereas colchicine and the Vinca alkaloids interfere with the polymerisation of tubulins, taxanes and epothilone inhibit their depolymerisation. 

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