Researchers have long wondered why some older people remain cognitively normal despite having abnormal levels of beta-amyloid in their brains, a hallmark of Alzheimer’s disease. While research has shown that older adults with Mild Cognitive Impairment (MCI), which often leads to Alzheimer’s, frequently have increased activity in the hippocampus compared to their cognitively healthy peers, scientists questioned what the hyperactivity represented. Was it helping to compensate for declining brain function or signaling onset of the disease?
Many people who have been affected by Alzheimer’s wonder how they can help combat this devastating disease. Volunteering to participate in research is one powerful way. Right now, at least 70,000 volunteers are needed for more than 150 active Alzheimer’s and related clinical trials and studies in the United States. All kinds of people, including healthy older adults, can join in this critical research.
Two new NIH-supported studies have shown that a person’s epigenome—the chemical modifications, or marks, on our DNA that turn gene activity on and off—may influence Alzheimer’s disease-related changes in the brain. The two groups of researchers examined brain tissue donated by volunteers with Alzheimer’s and those free of the disease and linked a specific epigenome marker, DNA methylation, with Alzheimer’s pathology in the brain.
Preliminary findings from a study by National Institute on Aging (NIA) scientists and colleagues showed that a blood test for Alzheimer’s-related proteins may accurately predict who might be at risk for the disease years before symptoms develop. The test measured the levels of several tau and amyloid proteins—the hallmarks of Alzheimer’s disease—in exosomes, microscopic organelles shed by brain cells.
Physical activity may help prevent atrophy of the hippocampus, a brain region important for learning and memory that often shrinks in the brains of people with Alzheimer’s disease. A recent study that looked at the rate of atrophy over 18 months in cognitively normal older adults suggests that physical activity may help prevent or delay this Alzheimer’s-related change.
Scientists have discovered gene variants that affect the function of immune cells in young, healthy people. Interestingly, many of these same gene variants are known risk factors for diseases that occur later in life, including Alzheimer’s and Parkinson’s. This linking of known gene risk factors for age-related neurological disorders to immune system functions, such as inflammation, offers new insights into Alzheimer’s and other disorders and may one day lead to promising therapies.