Unique amyloid buildup in brain blood vessel offers clue to Alzheimer’s development

Tuesday, November 22, 2016
Lead investigator in the study William Van Nostrand, PhD, a professor in the Department of Neurosurgery, says the findings stem from collaborative work with Steven Smith, PhD, a professor in the Department of Biochemistry & Cell Biology. Together with colleagues from both departments they have  mapped out the structural signature of amyloid that accumulates in brain blood vessels and compared it to the known structure of amyloid that accumulate in plaque around brain neurons.

Unique and alternating patterns

The team found that the subunits of the amyloid that accumulates in vessels line up uniquely and in alternating patterns, which presents in a near opposite pattern of amyloid buildup in plaque around neurons. “This discovery may help guide us to the development of a new diagnostic tool or therapeutic intervention for dementia patients who display this vessel pathology,” summarized Dr. Van Nostrand.
The study hypothesizes that the unique structure of this brain blood vessel amyloid could promote different pathological responses, ie, inflammation, which likely contributes differently to cognitive impairment and dementia than neuron amyloid.

Rates of dementia dropping in U.S.

In other research published online in JAMA Internal Medicine,  evidence suggests that rates of dementia across the United States are dropping. This could be because healthier behavior defers the onset of age-related dementia such as Alzheimer’s disease, as well as cancer, stroke and heart disease, the study states. Based on surveys of more than 20,000 individuals, the percentage of individuals 65 years or older with dementia declined from 11.6 percent in 2000 to 8.8 percent in 2012. The study was based on a nationally representative, population-based survey of individuals in the U.S.

Healthier behavior

Robert Friedland, M.D., professor of neurology at the University of Louisville School of Medicine,  attributes this reduction to healthier behaviors that defer onset of age-related dementia. Friedland studies brain disorders associated with aging and treats patients at University of Louisville Physicians.

“This work supports the past 20+ years of my research that has shown that it is possible to lower the risk of getting dementia with age. Lifestyle choices have consequences for the risk of Alzheimer’s disease, as well as cancer, stroke and heart disease,” Friedland said. “The reason that rates of dementia are declining is that people are living healthier lives than before.”