The effect of ISRIB has so far been tested only in mice, but its results “stunned” specialists. In just three days, the cognitive abilities of the older animals increased to youthful levels.
Scientists at the University of California, San Francisco have found that just a few doses of the experimental drug ISRIB can help reverse age-related memory and mental impairment in rodents.
It is noted that during research, the drug has shown the ability to restore memory function a few months after traumatic brain injury, eliminates cognitive impairment in Down syndrome, prevents hearing loss due to noise, fights some types of prostate cancer and even improves cognitive function in healthy animals.
“ISRIB’s extremely rapid effects show for the first time that a significant component of age-related cognitive losses may be caused by a kind of reversible physiological “blockage” rather than more permanent degradation”says Susanna Rosi from Neurological Surgery and of Physical Therapy and Rehabilitation Science.
The drug was discovered in 2013. ISRIB reboots the mechanisms of protein production in cells after they are blocked by one of the integrated stress reactions (ISR).
The mechanism of stopping protein synthesis is crucial for weeding out incorrectly functioning cells, but if it “fails,” it can lead to serious problems. Scientists believe that the basis of age-related mental decline may be the extensive activation of the ISR mechanism.
During the experiments, old mice were taught to get out of a water trap using a hidden platform. This task is usually difficult for older animals to master, but those who received small doses of ISRIB for three days coped with the task as well as young ones, and much better than animals of the same age who did not take the drug.
A few weeks after the initial therapy, the scientists put the same mice on a mental flexibility test. They trained them to find a way out of the maze, which changed every day. Rodents that received ISRIB three weeks earlier performed well, unlike non-treated rodents.
After examining the activity and anatomy of cells in the brain’s hippocampus (plays a key role in learning and memory) a day after a single dose of ISRIB, the researchers found that common signs of neuronal aging “disappeared literally overnight.”
The study authors are now trying to understand how long the cognitive benefits of ISRIB may last. According to them, in the future, the discovery may lead to the treatment of Alzheimer’s, Parkinson’s, multiple sclerosis, the consequences of TBI, Down’s syndrome and age-related cognitive changes.