Researchers may have found a way to delay or even prevent Alzheimer's disease. They discovered that pre-treatment of neurons with the anti-aging protein Klotho can prevent neuron death in the presence of the toxic amyloid protein and glutamate. Alzheimer's disease is the most frequent age-related dementia affecting 5.4 million Americans including 13 percent of people age 65 and older and more than 40 percent of people over the age of 85.