Nerve cells threatened by stroke or degenerative diseases may have a surprising new ally--microscopic spheres of carbon called buckyballs. A study published in tomorrow's Proceedings of the American Academy of Sciences describes how modified buckyballs--which soak up nerve-destroying chemicals--delay the onset of symptoms in mice suffering from Lou Gehrig's disease.
Naturally occurring molecules called free radicals wreak havoc within cells partly by stripping electrons from DNA and other sensitive biological molecules. They have been implicated in nerve degeneration in Lou Gehrig's disease, multiple sclerosis, and Parkinson's disease. When Laura Dugan, a neurologist at Washington University in St. Louis, heard that buckyballs absorb free radicals, she designed experiments to test whether or not buckyballs could slow down nerve cell death.
Standard buckyballs wouldn't work since they dissolve only in highly toxic compounds such as benzene. Instead, Dugan used buckyballs modified with six pairs of water soluble carboxylic acid molecules. Dugan and her colleagues added these antioxidant buckyballs to cultured neurons that had been starved of oxygen and glucose (which occurs after a stroke) for an hour. The buckyballs cut neuron death by 75%.
Dugan also pumped the buckyballs into the stomach cavity of mice bred to mimic Lou Gehrig's disease. Untreated, these mice become progressively weaker in the hind, then the front limbs. They eventually lose all muscle control, and die after about 130 days. Mice who received the modified buckyballs had their symptoms delayed by 10 days and survived 8 to 10 days longer than untreated mice.
The finding shows that buckyballs "act as an effective antioxidant," sweeping up free radicals, says Jonathan Gitlin, a pediatric neurologist at Washington University. Since free radicals have been implicated in many diseases, he says the modified buckyballs have broad therapeutic potential.