In a truly exciting area of neuroscience, researchers reported this week that they were able to identify specific changes in the brain that impair age-related memory and learning in elderly mice. These are the kind of gradual memory glitches that humans begin to experience in their late 40s and continue during the aging process. It appears that epigenetic changes -- changes in the way genes function but that do not involve changes in DNA -- cause this type of memory decline. But reversing these changes may yield treatments for cognitive loss.
Researchers in Germany determined that memory decline became impaired in aging mice around 16 months of age. Examining the mice, they found changes in the proteins that control gene expression in their brains. One particular change was found in enzymes called histone acetyltransferases. When the researchers treated the mice with a drug that reinstated the change in the enzymes and in the gene expression, they saw improved memory function in the mice. The study was published Thursday in the journal Science.
"This study presents a major advance in thinking about the role of histone modifications in synaptic plasticity and memory formation," J. David Sweatt, chairman of the University of Alabama at Birmingham department of neurobiology, said in a commentary accompanying the study. Sweatt, in a paper published recently, showed that drugs that affect histone acetyltransferases also benefit mice with Alzheimer's disease.
"These studies will hopefully lead to more effective prevention strategies to improve quality of life in the aged, as well as contribute to a better understanding of memory," Sweatt said in a news release.