Scientists research early stages of Alzheimer’s

Researchers at the Medical College of Wisconsin and at the University of Wisconsin-Madison are seeking to do what has only become possible in recent years: use imaging technologies to illuminate the early stages of Alzheimer’s disease and its effect on the still-living brain.

Since its discovery by Alois Alzheimer in 1906, researchers examining the brains of people who have died while struggling with dementia have been confounded by the presence of sticky proteins, called plaques, and twisted fibers of protein, called tangles.

Scientists are still not sure what causes them or exactly how they cause neural cell death and tissue loss, but the presence of plaques and tangles is the diagnostic hallmark of Alzheimer’s disease.

Until recently, “mapping out plaques and tangles could only be done after death, taking brain tissue and putting it under a microscope,” said Barbara Bendlin, associate professor of geriatrics and gerontology at UW-Madison’s School of Medicine and Public Health.

“Now, in the last few years, we have been able to examine these same pathologies in living humans,” she said.

That’s because of advancements in brain imaging technologies, such as magnetic resonance imaging, or MRI, and positron emission tomography, or PET scans.

The problem is that the behaviors that alert doctors to the possibility that someone has developed Alzheimer’s disease — memory loss, confusion, diminished problem-solving skills — appear years, even decades, after plaques and tangles have begun to form.

Bendlin and co-investigator MCW’s Shi-Jiang Li are using a $5.5 million four-year grant from the National Institute on Aging to employ advanced imaging technology to understand how communications between different areas of the brain change as the result of normal aging and of Alzheimer’s disease.

“Our study represents a critical step toward the development of personalized medicine for use in prevention and treatment of Alzheimer’s disease,” said Li, professor of biophysics, psychiatry and behavioral medicine and director of MCW’s Center for Imaging Research.

“What we are able to do,” Bendlin said, “is map out changes to structural connectivity, to anatomical connectivity, in very fine detail, and we suspect that in mapping out these and other changes is going help us better predict who will eventually develop the dementia due to Alzheimer’s.”

The hope is to someday develop simple tests that clinicians can use to intervene in the disease’s earliest stages.

Li and Bendlin are recruiting 300 people ages 55 to 90 to participate in the study.