24 May 2011
Viagra touted as MS treatment
by Kate Melville
Pharma giant Pfizer may soon may be cranking out even more little blue pills if the results from a recent study in Spain hold up. Sildenafil, the active ingredient in Viagra, may soon get a clinical trial for treating multiple sclerosis (MS) in humans thanks to an animal model study that demonstrated a practically complete recovery in 50 percent of the animals after eight days of treatment. The study, by researchers at Universitat Aut�noma de Barcelona, appears in Acta Neuropathologica.
MS is the most common chronic inflammatory disease of the central nervous system and one of the main causes of disability among adults. The disease is caused by the loss of myelin sheaths around the axons in the nervous system, affecting the ability of neurons to communicate and triggering neurodegeneration. There is currently no cure for the disease, although some drugs have proven effective in fighting symptoms and preventing it from progressing.
The research team studied the effects of sildenafil in an animal model of multiple sclerosis known as experimental autoimmune encephalomyelitis (EAE). The researchers demonstrated that a daily treatment with sildenafil after disease onset quickly reduced clinical signs, with a practically complete recovery in 50 percent of the cases after only eight days. The study notes how the drug reduced the infiltration of inflammatory cells into the white matter of the spinal cord, thus reducing damage to the nerve cell's axon and facilitating myelin repair.
Sildenafil is typically used in the treatment of erectile dysfunction and as such has become an enormous money-maker for Pfizer. However, recent studies in animal models of central nervous system pathologies have shown that in addition to vasodilation, sildenafil might also offer other neuroprotective effects. Acute (eg. cerebrovascular stroke) and chronic (eg. Alzheimer's) neuropathologies are two areas that other researchers are studying closely and the same research group behind the new MS study previously demonstrated that neuronal damage in animal models of traumatic brain injury could also be treated with sildenafil.
Source: Universitat Autonoma de Barcelona