Higher levels of a molecule called anthranilic acid could signal that a person is at increased risk of developing dementia and Alzheimer’s disease, according to a study.
The research, “Association of amine biomarkers with incident dementia and Alzheimer’s disease in the Framingham Study,” was published in the journal Alzheimer’s & Dementia.
In a search for new biomarkers to diagnose and track the progression of dementia and Alzheimer’s, researchers analyzed levels of 217 molecules known as metabolites that circulate in blood.
They looked at blood samples from 2,067 people who participated in the Framingham Heart Study, which was conducted to identify risk factors for heart disease. Ninety-three people in a subgroup of patients developed dementia during a mean follow-up period of 15.6 years, they discovered. Their average age was 56.
Researchers then looked for an association between metabolite levels and the risk of a person developing the neurodegenerative diseases after 10 years.
Increased levels of anthranilic acid were associated with greater risk of dementia, the team discovered. Increased levels of the neurotransmitter glutamate and lower levels of taurine and hypoxanthine, a precursor of uric acid, also seemed to be associated with increased risk of developing dementia.
Importantly, anthranilic acid is known to be involved in glutamate excitotoxicity, a process in which glutamate damages neurons by promoting their excessive and unregulated activity.
Although the results are preliminary, researchers believe there are several reasons why the metabolites they identified show promise as biomarkers of dementia and Alzheimer’s.
“First, anthranilic acid is produced during the degradation of tryptophan, an essential amino acid,” Dr. Sudha Seshadri, the study’s senior author, said in a news release. “Interestingly, other compounds produced through the same reactions have been reported as protective or deleterious for neurons and could constitute valuable drug targets.
“Second, this potential marker could also be used to identify groups of persons at higher risk of developing dementia, which could improve the efficiency of clinical trials and, in the future, detect persons that would benefit the most from a preventive treatment.”
This study was the first to use information from the Framingham Heart Study to search for new biomarkers for dementia and Alzheimer’s.
“As the field of [Alzheimer’s disease] epidemiology is only beginning to integrate the metabolomics approach, it is likely that fruitful collaborations and innovative ways to analyze these data will follow,” said Dr. Vincent Chouraki, the study’s lead author.