Colchicine and its various physicochemical and biological aspects

Natural (-)-(aS, 7S)-colchicine, an alkaloid and toxic natural product is a secondary plant metabolite, obtained from Colchicum autumnale also known as 'meadow saffron'. Colchicine, among the Indian medicinal plants, is contained in the corms of Colchicum luteum and the seeds of Iphigenia, to the extent of about 0.25 and 0.9 % respectively. These plants are not available in sufficient quantities to warrant any commercial utilization. Natural (-)-colchicine has only one stereogenic centre: carbon-7. The biosynthesis of colchicine involves amino acid precursors, phenylalanine and tyrosine. It is used to treat rheumatic complaints, especially gout, also prescribed for its cathartic and antiemetic effects and also in initial treatment for pericarditis. It is also being investigated for its use as an anti-cancer drug. Colchicine itself is too toxic for human use as an anti-tumour drug and hence its derivatives have been used. Colchicine poisoning has been reported in patients with kidney or liver failure. In neurons, axoplasmic transport is disrupted by colchicine. It is used widely off-label by naturopaths for a number of treatments, including the treatment of back pain and also used as an anti-inflammatory agent for long-term treatment of Behcet's disease.