BOSTON, Aug. 27--In laboratory tests, vitamin E prevented the death of brain cells exposed to a toxic protein found in the brains of patients with Alzheimer's disease, it was reported here today.
The protein, amyloid beta peptide (AB), is the major constituent of the senile plaques found in Alzheimer brains, and it generates oxygen free radicals that attack and kill brain cells, said Allan Butterfield, Ph.D., professor of chemistry and director of the Center for Membrane Sciences of the University of Kentucky. He presented his findings at a national meeting of the American Chemical Society, the world's largest scientific society.
Now, Dr. Butterfield says, he has become the first to see the actual death and survival of brain cells in tests of AB and antioxidants.
In one study, Dr. Butterfield added AB to the normal brain cells of test rodents and watched as all the cells died. He then pretreated rodent brain cells with Vitamin E before adding the AB. The Vitamin E prevented oxidation and cell death in almost every case, he said.
Another study, done in collaboration with colleague Mark Mattson, achieved even more dramatic result: Here Dr. Butterfield added AB to brain cells that had been genetically altered to produce antioxidants, in this case a protein called BCL-2. All of the genetically altered cells survived, he said. "The tests provide a model for how Alzheimer brain cells die-one I hope might someday light a path toward better therapies," he said.
In 1994, Dr. Butterfield postulated that AB generates oxygen free radicals that kill cells. His work helped to promote an explosion of research to determine whether antioxidants, such as vitamin E, could keep the cells alive.
Free radicals are molecules with one or more unpaired electrons that can unite
with the molecules in healthy cells and ultimately kill them; antioxidants are
molecules that can destroy these damaging free radicals. "I think it very
Contact: Nancy Blount
American Chemical Society