A study from Wake Forest University School of Medicine found that even moderate drinking can accelerate brain shrinkage and amplify the formation of amyloid plaques associated with Alzheimer's disease. Using mouse models, researchers found that continued exposure to alcohol disrupts metabolism, raises blood sugar levels and increases the risk of other diseases, including type 2 diabetes and cardiovascular disease.
A study shows that even moderate alcohol consumption can accelerate brain degeneration and amplify the formation of amyloid plaques, thereby exacerbating the risk of Alzheimer's disease.
Alzheimer's disease is the most common form of dementia, accounting for 60% to 80% of dementia cases, according to the Alzheimer's Association. Although current research suggests that alcohol use disorder is a risk factor for Alzheimer's disease, the impact of alcohol use disorder on Alzheimer's disease pathology remains an area that requires continued research.
In a preclinical study, scientists at Wake Forest University School of Medicine found that even moderate amounts of alcohol accelerate brain atrophy, the loss of brain cells, and increase the number of amyloid plaques, the buildup of toxic proteins seen in Alzheimer's disease.
The research was published in the journal Neurobiology of Disease.
"These findings suggest that alcohol may accelerate a pathological cascade in the early stages of Alzheimer's disease," said Dr. Shannon Macauley, associate professor of physiology and pharmacology at Wake Forest University School of Medicine.
The study was led by Jeffrey Weiner, Ph.D., professor of physiology and pharmacology at Wake Forest University School of Medicine, and was conducted through the School of Medicine's Alzheimer's Disease Research Center and Translational Alcohol Research Center.
Research methods and findings
Using a mouse model of Alzheimer's disease-related pathology, the researchers adopted a 10-week chronic drinking method, allowing the mice to choose between drinking water or alcohol, mimicking human drinking behavior. They then explored how voluntary, moderate alcohol consumption alters healthy brain function and behavior, and whether alcohol alters pathological changes associated with the early stages of Alzheimer's disease.
Researchers found that alcohol worsens brain atrophy and leads to an increase in the number of amyloid plaques, which include more small plaques, which may set the stage for plaque proliferation later in life.
Interestingly, the researchers also noticed that acute alcohol withdrawal increased levels of amyloid-beta, a major component of Alzheimer's disease amyloid plaques.
Further analysis showed that long-term alcohol exposure can adversely regulate brain and peripheral metabolism - another way to accelerate the pathological changes in Alzheimer's disease. Macauley has previously shown that elevated blood sugar increases amyloid-beta and amyloid plaques. In the current study, researchers found that even moderate drinking can lead to elevated blood sugar levels and elevated markers of insulin resistance, which not only increases the risk of Alzheimer's but also other conditions such as type 2 diabetes and cardiovascular disease.
Significance of research
Studies have also found that moderate drinking can change anxiety and dementia-related behaviors.
"These preclinical findings suggest that even moderate alcohol consumption can cause brain damage. Alcohol consumption may be a modifiable risk factor for Alzheimer's disease and dementia," Macauley said.