In another significant medical discovery in Perth, a team from Edith Cowan University has found that people with gut disorders may be at great risk of Alzheimer’s disease.
The world-first study could have a major impact on how people are diagnosed and treated for the disease, which is the most prevalent form of dementia and has no known curative treatments.
It will help researchers understand the causes of the conditions and know what to target to create more effective treatments — with cholesterol emerging as potential key.
Previous observational studies have suggested a relationship between Alzheimer’s and gastrointestinal tract disorders but what underpins these relationships had been unclear, until now.
ECU’s Centre for Precision Health analysed large sets of genetic data and was able to confirm a genetic link between Alzheimer’s and multiple gut disorders.
Research lead Dr Emmanuel Adewuyi said it was the first comprehensive assessment of the genetic relationship.
“This improves our understanding of the causes of these conditions and identifies new targets to investigate to potentially detect the disease earlier and develop new treatments for both types of conditions,” Dr Adewuyi said.
Centre director and study supervisor Professor Simon Laws said while the study did not conclude gut disorders caused Alzheimer’s or vice versa, the results were highly valuable.
“These findings provide further evidence to support the concept of the ‘gut-brain’ axis, a two-way link between the brain’s cognitive and emotional centres, and the functioning of the intestines,” Professor Laws said.
Is cholesterol a key?
When researchers conducted further analysis into the shared genetics, they found other important links between Alzheimer’s and gut disorders – such as the role cholesterol may play.
Dr Adewuyi said abnormal levels of cholesterol were shown to be a risk for both Alzheimer’s and gut disorders.
“Looking at the genetic and biological characteristics common to AD and these gut disorders suggests a strong role for lipids metabolism, the immune system, and cholesterol-lowering medications,” he said.
“While further study is needed into the shared mechanisms between the conditions, there is evidence high cholesterol can transfer into the central nervous system, resulting in abnormal cholesterol metabolism in the brain.
“There is also evidence suggesting abnormal blood lipids may be caused or made worse by gut bacteria (H.pylori), all of which support the potential roles of abnormal lipids in AD and gut disorders.
“For example, elevated cholesterol in the brain has been linked to brain degeneration and subsequent cognitive impairment.”
Hope for the future
The cholesterol link could prove vital in treating Alzheimer’s in the future.
While there are currently no known curative treatments, the study’s findings suggest statins could be therapeutically beneficial in treating both Alzheimer’s and gut disorders.
“Evidence indicates statins have properties which help reduce inflammation, modulate immunity and protect the gut,” Dr Adewuyi said.
However, he said there was a need for more studies and patients needed to be assessed individually to judge whether they would benefit from statin use.
The research also indicated diet could play a part in treating and preventing Alzheimer’s and gut disorders.