An Israeli study has discovered a biological mechanism that could explain how challenging mental and physical activity can delay the development and onset of Alzheimer’s disease, the Israeli newspaper Ha’aretz reports.
The study, led by Boaz Barak of Tel Aviv University, was published in the September issue of the journal Translational Psychiatry.
“As a rule, the more intellectually stimulating and physically challenging a patient’s lifestyle, the slower the disease develops,” Barak told the newspaper. “What was missing was the biological explanation behind this rule. What exactly about an environment rich in stimuli stalls the disease at the cellular level?”
Alzheimer’s is usually accompanied by the degeneration of brain cells and memory loss. It is characterized by decreased levels of proteins responsible for communication between the nerve cells and the brain. This decrease in proteins is what harms the patients’ cognitive and physical abilities.
The levels of these specific proteins are boosted by exposure to intellectual stimuli and physical activity.
The researchers compared the amount of microRNA, the molecules responsible for regulating the amount of proteins in cells in healthy rodents, to the amount of microRNA in rodents that served as a model for Alzheimer’s disease.
In the process, the team compared the amount of microRNA chains in mice that were raised in stimuli-rich environments with those raised in normal environments.
“The same microRNA chains that were found to have changed as a result of Alzheimer’s or stimulating environments are also responsible for the regulation of proteins that affect the communication between nerve cells and the brain,” Barak told Ha’aretz.
“The amount of those chains in the cell rose after exposure to Alzheimer’s and caused a decrease in the amount of proteins, which is liable to damage nerve function in the brain. On the other hand, exposure to stimuli-rich environments showed a decrease in the amount of such microRNA chains, which resulted in an increase in proteins, which could lead to an increase in nerve function in the brain.”
The scientists also discovered a number of microRNA chains that underwent significant changes during the early stages of the disease. This information could be used to establish an early detection test, possibly with a simple blood sample.
“Studies conducted over the last few years have proved that it’s possible to isolate and quantify the amount of various microRNA chains through simple blood tests, and I hope that within the next few years, it will be possible to detect changes to microRNA levels in the brain itself, and not just blood,” Barak said.
The findings could be used to create patient-specific treatments, he observed. It may pave the way for some form of Alzheimer’s medication.