Botulinum toxin (Molecule of the Month for March 2008)
Botox, Myobloc, Dysport
Botulinum toxin is a neurotoxin protein produced by the bacterium Clostridium botulinum. It is one of the most poisonous naturally occurring substances in the world, and it is the most toxic protein, just 0.000 000 7 grams would kill most adults. Though it is highly toxic, it is used in minute doses both to treat painful muscle spasms, and as a cosmetic treatment in some parts of the world. It is sold commercially under the brand names Myobloc, Botox and Dysport for this purpose. Botox is manufactured by Allergan Inc (U.S.) for both therapeutic as well as cosmetic use. The formulation is best stored at cold temperature of 2-8 degrees Celsius. Dysport is a therapeutic formulation of the type A toxin developed and manufactured in Ireland and which is licenced for the treatment of focal dystonias and certain cosmetic uses in many territories world wide.
Cosmetically desirable effects of Botox were first discovered by Vancouver-based cosmetic surgeons Drs. Alastair and Jean Carruthers. The serendipitous discovery occurred when the husband-and-wife team observed the softening of patients' frown lines following treatment for eye muscle disorders, leading to clinical trials and subsequent FDA approval for cosmetic use in April 2002. As of 2006, Botox injection is the most common cosmetic operation in the United States. All cosmetic treatments are of limited duration, and can be as short a period as six weeks, but usually one reckons with an effective period of between 3 and 8 months. At the extremely low doses used medicinally, botulinum toxin has a very low degree of toxicity. Botox has also been approved for the treatment of excessive underarm sweating. The acceptance of Botox use for the treatment of spasticity and muscle pain disorders is growing, with approvals pending in many European countries and studies on headaches (including migraine), prostatic symptoms, asthma, obesity and many other possible indications are ongoing.
Between 1817 and 1822 the German physician and poet Justinus Kerner described botulinium toxin, using the terms "sausage poison" and "fatty poison", as this bacterium often causes poisoning by growing in badly handled or prepared meat products. He first conceived a possible therapeutic use of botulinium toxin. In 1870, Muller (another German physician) coined the name botulism, from Latin botulus = "sausage". In 1895, Emile van Ermengem first isolated the bacterium Clostridium botulinum. In 1944, Edward Schantz cultured Clostridium botulinum and isolated the toxin, and, in 1949, Burgen's group discovered that botulinum toxin blocks neuromuscular transmission.
Formal Chemical Name (IUPAC)
Update by Karl Harrison
(Molecule of the Month for March 2008 )