Amyotropic lateral sclerosis (ALS, often called Lou Gehrig's disease) is a paralyzing disorder caused by the death of motor neurons in the spinal cord and brainstem. It is currently incurable, and patients typically die within three to five years of disease onset. However, a new treatment approach delays the progression of the disease in an animal model, reports a paper in the January issue of Nature Neuroscience.
Unlike patients with other neurodegenerative disorders like Alzheimer's or Parkinson's disease, ALS patients have no cognitive impairment. The disease often strikes healthy individuals in their prime, and more than 90% of ALS patients have no family history of neurodegenerative disease. ALS patients usually notice muscle weakness first in their limbs (limb-onset) but in about 25%, the motor neurons in the brainstem degenerate first (bulbar-onset). Bulbar-onset ALS progresses faster and causes life-threatening respiratory problems sooner than limb-onset ALS; these patients typically survive only for 12 to 18 months after becoming ill.
Peter Carmeliet and colleagues delivered recombinant VEGF, a growth factor known to promote neuron growth and survival, directly into the brains of rats with ALS symptoms. This treatment caused the rats to survive 3.5 times longer than untreated animals and delayed the onset of paralysis. To date, this is among the greatest therapeutic effects reported with growth-factor treatment in ALS.
Direct delivery to the brain was particularly effective in rats suffering from forelimb-onset ALS (the equivalent of human bulbar-onset cases), stimulating motor neuron survival in the brainstem. The authors also report that the VEGF was transported from axons back to cell bodies elsewhere in the brain, and that it helped preserve synapses between motor neurons and muscles in these animals.
This work may help revive interest in clinical trials using growth factors as a potential treatment for ALS, and also establishes a new rat ALS model that could be used to evaluate novel treatments.
Peter Carmeliet (University of Leuven, Belgium)
Tel: +32 16 34 57 74, E-mail: email@example.com
Also published online.
(C) Nature Neuroscience press release.
Message posted by: Trevor M. D'Souza