The National Institute of Environmental Health Sciences, a component of the National Institutes of Health, provided $1.25 million to University of Wisconsin-Madison scientists for the transthyretin study. The scientists will present their findings October 26 at the 34th annual meeting of the Society for Neuroscience in San Diego, Calif.

"The results of this study are promising," said Kenneth Olden, Ph.D., director of the NIEHS. "More studies are needed to understand how transthyretin can be used in treating Alzheimer's patients."

Alzheimer's disease progresses when a toxic protein, known as "beta-amyloid," attacks the brain's nerve cells involved in learning and memory. The beta-amyloid creates sticky plaques and tangles that gradually disable nerve cells, producing memory loss. Transthyretin appears to protect brain cells by intercepting the beta-amyloid and preventing it from interacting with the brain tissue.

"Based on the results of animal studies, we know that the disease process depends in large part on the delicate balance between the 'good' transthyretin protein and the 'bad' beta-amyloid protein," says Dr. Jeff Johnson, associate professor at the University of Wisconsin's School of Pharmacy and lead author on the study. "In Alzheimer's patients, the 'bad' proteins significantly outnumber the 'good' proteins."

Johnson discovered the effect of transthyretin while studying mice genetically engineered with defective genes taken from human patients with early-onset Alzheimer's disease. As expected, the defective genes produced mice with higher-than-normal levels of the toxic beta-amyloid protein. These mice did not, however, exhibit symptoms
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Contact: John Peterson
peterso4@niehs.nih.gov
919-541-7860
NIH/National Institute of Environmental Health Sciences
25-Oct-2004