A study from Edith Cowan University in Australia has confirmed the genetic link between gut disorders and Alzheimer’s disease, which could lead to earlier detection and potential new treatments.
Alzheimer’s disease destroys memory and the ability to think and is the most common form of dementia. It has no known cures and is expected to affect over 82 million people and cost $2 trillion by 2030.
Previous observational studies have suggested a link between Alzheimer’s disease and disorders of the gastrointestinal tract, but what underlies these links was unclear until now.
This work, published in the scientific journal ‘Communications Biology’, now provides new information on these relationships by confirming a genetic link between Alzheimer’s disease and multiple intestinal disorders.
The study analyzed large genetic datasets on Alzheimer’s disease and several studies on gut disorders, each involving about 400,000 people.
Research director Emmanuel Adewuyi said this is the first comprehensive assessment of the genetic relationship between Alzheimer’s disease and multiple bowel disorders.
The team found that people with Alzheimer’s disease and gut disorders share genes, which is important for many reasons.
“The study provides new insights into the genetics underlying the observed coexistence of Alzheimer’s disease and gut disorders. This improves our understanding of the causes of these conditions and identifies new targets to study to potentially detect the disease. earlier and develop new treatments for both types of conditions,” Dr. Adewuyi said.
Although the study does not conclude that intestinal disorders cause Alzheimer’s disease or vice versa, the results are extremely valuable. These results provide further evidence supporting the concept of the “gut-brain axis,” a two-way link between the cognitive and emotional centers of the brain and the functioning of the gut.
Is cholesterol the key?
When researchers delved into shared genetics, they discovered other important links between Alzheimer’s disease and gut disorders, such as the role cholesterol may play.
Abnormal cholesterol levels have been shown to be a risk for both Alzheimer’s disease and intestinal disorders. “The study of genetic and biological characteristics common to Alzheimer’s disease and these intestinal disorders suggests that lipid metabolism, the immune system and cholesterol-lowering drugs play an important role”, details Adewuyi.
Although the mechanisms common to both diseases require further study, there is evidence that high cholesterol can reach the central nervous system and cause abnormal cholesterol metabolism in the brain.
“There is also evidence to suggest that abnormal blood lipids may be caused or worsened by gut bacteria (“H. pylori”), supporting a potential role of abnormal lipids in Alzheimer’s disease and intestinal disorders. For example, high cholesterol in the brain has been linked to brain degeneration and subsequent cognitive decline,” says Adewuyi.