Researchers at the School of Medicine have teamed up with colleagues at the VA-Palo Alto Health Care System to assemble a powerful resource for Alzheimer’s disease researchers: a brain bank of samples from people with Alzheimer’s or similar neurodegenerative diseases.

The unusual collection gives researchers a glimpse into the structural and molecular changes that lead up to the memory loss and disorientation that characterizes Alzheimer’s disease.

Slides made from brain tissue available at the brain bank show patterns of plaques and tangles that indicate the onset of Alzheimer’s disease. The brain bank provides tissue samples to researchers nationwide who are studying diseases related to dementia. Photo: Courtesy of The Brain Bank

The brain bank is part of the Stanford/VA Alzheimer’s Disease Center directed by Jerome Yesavage, MD, professor of psychiatry and behavioral sciences. This center is part of the Aging Clinical Research Center, supported by both Stanford and the VA and the National Institute on Aging. It currently has more than 1,000 samples from about 40 brains, available to researchers at any academic research center.

Ahmed Salehi, MD, PhD, senior research associate in neurology and neurological sciences and coordinator of the brain bank, said that there are no animal models for Alzheimer’s that perfectly mimic the disease in humans. "Studying human samples is the best way to understand the process," Salehi said. Investigating the disease in humans

is hindered by the fact that the disease can’t be diagnosed except by examining brain tissue, usually after death.

Because many of the brain bank’s donors were treated at the VA-Palo Alto Health Care System, detailed medical records go back much farther than in people who have switched from doctor to doctor, shedding their medical records along the way. These records help researchers put their findings in context. Researchers may discover that certain brain features show up only in people whose disease progressed quickly, who developed the disease early in life or who had specific symptoms such as trouble sleeping.

Salehi said samples from this brain bank offer a unique resource compared with other brain banks that exist throughout the world. These samples are taken sooner after death than at other brain banks, so any findings are a result of the disease rather than from changes that took place after death. The samples are also preserved in three formats suitable for different types of research.

Findings from studies using these samples may eventually help clarify how the brain changes during the course of Alzheimer’s disease and lead to new ways of preventing or treating the disease.

Salehi said that because people voluntarily agree to donate their brains before death — and therefore before an Alzheimer’s diagnosis is confirmed — some of the samples are from Alzheimer’s patients at different stages of the disease while other samples reveal that the donor had an unrelated neurodegenerative disease or no physical changes in the brain. These particular samples are still of interest to researchers who want to understand what distinguishes different forms of dementia or to use as controls for experiments using Alzheimer’s samples.

Researchers can request samples from specific brain areas based on criteria such as age, sex, delay between death and autopsy, or other factors they are interested in studying. The requests are reviewed by a monthly board, which is responsible for approving requests. Researchers pay only shipping costs for the samples and must credit the brain bank in any publications.

The brain bank is funded by the National Institute on Aging. For more information on the brain bank, visit http://www.stanford.edu/~yesavage/ACRC.html or contact asalehi@stanford.edu.