The Sanders-Brown Center on Aging at the University of Kentucky has been around for nearly half a century. During that time, they have built an international reputation for cutting-edge research into a disease that kills more people each year than breast and prostate cancer combined – Alzheimer’s disease. The research underway at Sanders-Brown has several components, one of which is exploring ways to detect Alzheimer’s disease earlier in a person’s life.
A recent study published by the laboratory of Donna Wilcock, Ph.D., holder of the endowed Robert P. and Mildred A. Moores Chair in Alzheimer’s disease, shows promising results for a blood test that could be used to identify Alzheimer’s changes in the brain before any symptoms appear, which could lead to the use of preventive treatments before any memory loss occurs.
In their article published in Alzheimer’s and dementia: the journal of the Alzheimer’s Association, the researchers note that detection of pathogenic pathology associated with Alzheimer’s disease and vascular contributions to cognitive impairment and dementia (VCID) is limited to cognitive assessments and neuroimaging such as MRI and PET. Due to recent technological developments, blood biomarkers of the disease are now available that the Sanders-Brown team believe could be beneficial in the diagnosis of Alzheimer’s disease and other dementias. A biomarker – short for biological marker – is a measurable indicator that captures what is happening in a cell or organism at a given time.
Zachary Winder, a MD/PhD student at the UK College of Medicine, led the work within the Wilcock Laboratory which used the extensive bank of samples found in the Alzheimer’s Disease Research Center autopsy cohort in United Kingdom, which consists of Kentucky residents who agreed to donate their brains at the time of death. For this study, the researchers identified samples from participants whose blood had been collected and banked within two years of their death. They then tested blood samples from 90 participants for a variety of proteins with the aim of identifying biomarkers in the blood that could predict changes in the brain that may have contributed to dementia.
They believe their findings support further study of blood biomarkers as a clinical screening tool for Alzheimer’s disease and VCID. “This study provides evidence that a blood test could be used to estimate the presence of Alzheimer’s disease changes and blood vessel damage in the brain. We have identified proteins in the blood that indicate protein changes and changes in the brain known to cause dementia. A drop in beta-amyloid in the blood indicates Alzheimer’s disease amyloid plaques in the brain,” said Wilcock, associate director at Sanders-Brown. Protein markers of inflammation in the blood were also associated with higher amyloid plaques in the brain. We also looked at proteins that may have a relationship to damage to blood vessels in the brain. We found that inflammation proteins in the blood were linked to damage. to the blood vessels of the brain.
Wilcock, Winder and the rest of the research team agree that establishing biomarkers that allow physicians to diagnose and monitor patients is a crucial step toward identifying at-risk, but not yet symptomatic, patients who may be more responsive to potential therapies.
Blood samples can be easily obtained, even during primary care visits. Developing a blood test would eliminate the need for expensive and specialized PET scans or invasive and uncomfortable lumbar punctures.”
Donna Wilcock, Ph.D., Robert P. and Mildred A. Moores Endowed Chair in Alzheimer’s Disease
Through the UK Community Cohort, researchers have found through autopsies that there are mixed causes of dementia and that proteins in the blood are associated with brain changes. They believe these findings provide further evidence that blood biomarkers have strong potential for the diagnosis of Alzheimer’s disease and other causes of dementia.
Until recent years, the only way to know if someone had Alzheimer’s disease or a related dementia was after death through an autopsy. Advances in biomarker research, like this recent Sanders-Brown study, allow researchers to see changes in the brain while people are alive, monitor disease progression, and test the effectiveness of potential treatments.