People with Alzheimer's disease have fat deposits in the brain. For the first time since the disease was described 109 years ago, researchers have discovered accumulations of fat droplets in the brain of patients who died from the disease and have identified the nature of the fat. The breakthrough, published in the journal Cell Stem Cell, opens up a new avenue in the search for a medication to cure or slow the progression of Alzheimer's disease.
Over 47.5 million people worldwide have Alzheimer's disease or some other type of dementia, according to the World Health Organization. Despite decades of research, the only medications currently available treat the symptoms alone.
This study highlights what might prove to be a missing link in the field. Researchers initially tried to understand why the brain's stem cells, which normally help repair brain damage, are unresponsive in Alzheimer's disease. They were astonished to find fat droplets near the stem cells, on the inner surface of the brain in mice predisposed to develop the disease.
The researchers examined the brains of nine patients who died from Alzheimer's disease and found significantly more fat droplets compared with five healthy brains. They then used an advanced mass spectrometry technique to identify these fat deposits as triglycerides enriched with specific fatty acids, which can also be found in animal fats and vegetable oils.
"We discovered that these fatty acids are produced by the brain, that they build up slowly with normal aging, but that the process is accelerated significantly in the presence of genes that predispose to Alzheimer's disease", the researchers explained. "In mice predisposed to the disease, we showed that these fatty acids accumulate very early on, at two months of age, which corresponds to the early twenties in humans. Therefore, we think that the build-up of fatty acids is not a consequence but rather a cause or accelerator of the disease."
Fortunately, there are pharmacological inhibitors of the enzyme that produces these fatty acids. These molecules, which are currently being tested for metabolic diseases such as obesity, could be effective in treating Alzheimer's disease. "We succeeded in preventing these fatty acids from building up in the brains of mice predisposed to the disease. The impact of this treatment on all the aspects of the disease is not yet known, but it significantly increased stem cell activity," the researchers said.
The researchers are continuing their experiments to verify whether this new approach can prevent or delay the problems with memory, learning and depression associated with the disease.
Based on material originally posted by University of Montreal.