Dicoumarol

Dicoumarol (INN) or dicumarol (USAN) is an anticoagulant that functions as a vitamin K antagonist (similar to warfarin, for which it was the inspiration). It is also used in biochemical experiments as an inhibitor of reductases.

Dicoumarol is a natural chemical substance of combined plant and fungal origin. It is a derivative of coumarin, a bitter substance made by plants that does not itself affect coagulation, but which is (classically) transformed in mouldy feeds or silages by a number of species of fungi, into active dicoumarol. Dicoumarol does affect coagulation, and was discovered in mouldy wet sweet-clover hay, as the cause of a naturally occurring bleeding disease in cattle.

Identified in 1940, dicoumarol became the prototype of the 4-hydroxycoumarin derivative anticoagulant drug class. Dicoumarol itself, for a short time, was employed as a medicinal anticoagulant drug, but since the mid-1950s has been replaced by its simpler derivative warfarin, and other 4-hydroxycoumarin drugs.

It is given only orally, and it acts within two days.

Mechanism of action

Like all 4-hydroxycoumarin drugs it is a competitive inhibitor of vitamin K, preventing the formation of prothrombin. Administration of vitamin K is therefore the antidote for dicoumarol toxicity. The toxicity and the antidote effectiveness are measuring with the prothrombin time (PT) blood test.

Uses

Dicoumarol was used along with heparin, for the treatment of deep venous thrombosis. Unlike heparin, this class of drugs may be used for months or years.

References

• Cullen J, Hinkhouse M, Grady M, Gaut A, Liu J, Zhang Y, Weydert C, Domann F, Oberley L (2003). "Dicumarol inhibition of NADPH: quinone oxidoreductase induces growth inhibition of pancreatic cancer via a superoxide-mediated mechanism.". Cancer Res 63 (17): 5513–20. PMID 14500388. 
• Mironov A, Colanzi A, Polishchuk R, Beznoussenko G, Mironov A, Fusella A, Di Tullio G, Silletta M, Corda D, De Matteis M, Luini A (2004). "Dicumarol, an inhibitor of ADP-ribosylation of CtBP3/BARS, fragments golgi non-compact tubular zones and inhibits intra-golgi transport.". Eur J Cell Biol 83 (6): 263–79. doi:10.1078/0171-9335-00377. PMID 15511084. 
• Abdelmohsen K, Stuhlmann D, Daubrawa F, Klotz L (2005). "Dicumarol is a potent reversible inhibitor of gap junctional intercellular communication.". Arch Biochem Biophys 434 (2): 241–7. doi:10.1016/j.abb.2004.11.002. PMID 15639223. 
• Thanos C, Liu Z, Reineke J, Edwards E, Mathiowitz E (2003). "Improving relative bioavailability of dicumarol by reducing particle size and adding the adhesive poly(fumaric-co-sebacic) anhydride.". Pharm Res 20 (7): 1093–100. doi:10.1023/A:1024474609667. PMID 12880296. ]

External links

• DDB 30166