Botulinum toxin therapy for pain and inflammatory disorders: mechanisms and therapeutic effects.
Botulinum toxin (BTX) injections are a well-recognised therapeutic modality for the treatment of regional involuntary muscle disorders and recently BTX has been used for treatment of pain and inflammatory disorders. The primary purpose of this review is to discuss the mechanism of action of therapeutic BTX in light of both the traditional understanding of BTX pharmacological effects as well as new observations. The review will deal with clinical observations and relevant animal experimentation. The data and hypotheses presented are not only relevant to botulinum toxin technology but will certainly prove important in the basic mechanisms of some of the diseases where botulinum toxin has been successfully applied. BTX used clinically comprises botulinum neurotoxin (BoNT) complexed with non-toxic proteins. The non-toxic components of the BTX complexes stabilise the labile BoNT during purification and formulation as a therapeutic. The complex proteins may also have unrecognised clinical significance such as slowing diffusion in tissues or imparting stability. The mechanisms of BTX formulations acting on SNARE proteins are briefly reviewed providing a basis for BTX clinical applications. The potential for design of improved botulinum toxins and formulations is addressed.
Borodic
G E
GE
Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA. borodic@aol.com
Acquadro
M
M
Johnson
E A
EA
D000818:Animals; D001341:Autonomic Nervous System / Q000187:drug effects; D001905:Botulinum Toxins / Q000494:pharmacology / Q000627:therapeutic use*; D005157:Facial Pain / Q000188:drug therapy; D006801:Humans; D006967:Hypersensitivity / Q000150:complications; D007249:Inflammation / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D008565:Membrane Proteins / Q000187:drug effects; D008881:Migraine Disorders / Q000188:drug therapy; D009069:Movement Disorders / Q000188:drug therapy; D009468:Neuromuscular Diseases / Q000188:drug therapy; D010146:Pain / Q000188:drug therapy*; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins
D008565:Membrane Proteins; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins; D001905:Botulinum Toxins