High Mental Activity Protects Against Alzheimer's Disease in Mice
06.12.06
Tampa, FL. (June 12, 2006) - Researchers at the Byrd Alzheimer's Research Institute in Tampa, Florida have determined that Alzheimer's mice placed in a mentally-enriched environment outperform similar mice in traditional environments and behaviorally match those not suffering from the disease.
The research, if extended to people with the disease, demonstrates that living a life full of mentally challenging activities can slow and even protect against the development of Alzheimer's disease.
"What we are seeing in this research is that mice having the same characteristics as humans with Alzheimer's are able to perform well, even at the same level as mice without Alzheimer's, if housed in a mentally challenging, cognitively enriched environment. The mental stimulation provided in this environment appears to stymie mental impairment. After months of mental stimulation, it was impossible to differentiate these mice from the behaviorally normal, healthy mice,'' said Huntington Potter, Ph.D., investigator on the project and chief executive officer of the Byrd Research Institute.
In their initial 2004 report, Potter and his collaborators at the Institute found that even aged, mentally-impaired Alzheimer's mice show improved memory after being placed in a mentally-stimulating environment for several months. He said this successful Alzheimer's mouse experiment will be tested in Alzheimer's patients and that sessions of mentally-stimulating activities would be given on a regular basis. It is hoped that such cognitive-stimulation will stabilize or even improve the memory function of Alzheimer's patients.
"If individuals with Alzheimer's can benefit from living in a cognitively-enriched environment, then these individuals could live fuller, longer and more productive lives. Finding a cure for Alzheimer's will be accomplished in steps and research into mental exercises is one very important step,'' said Potter.
A high level of mental activity throughout life has been suggested to lower the risk of Alzheimer's disease, but it is impossible to assess the preventative potential of environmental enrichment in a controlled clinical study. The research done at the Byrd Alzheimer's Institute tackled this question by using Alzheimer's mice in a well-controlled, blind study. The experiments showed that the Alzheimer's mice living in the enriched environment outperformed those in standard housing when tested at an older age. The treated mice also were behaviorally indistinguishable from the mice without the Alzheimer's disease.
Mice used in the experiments develop a number of Alzheimer's characteristics in their brains as they age, along with the hallmark of the disease – memory impairment. In the experiment, young adult mice were placed into either an enriched environment, or a standard environment to measure the effects of environment on their mental abilities when they became older. The enriched environment included toys, mazes, tunnels, and social activity, along with cognitive stimulation sessions in novel environments every few days. All of this served to protect the mice from memory problems, while promoting beneficial changes in their brain.
"Not only did we find that mental stimulation throughout life protects memory in Alzheimer's mice, but we found beneficial changes in their brains as well," said David Costa, Ph.D., member of the investigative team. "A number of genes that provide for the growth and maintenance of neurons were more active. In addition, amyloid, a pathogenic protein that accumulates in Alzheimer's brains, was decreased."
The results indicate that the enriched environment protected against memory impairment through a dual mechanism, including changes in both gene activity and amyloid levels within the brain.
Alzheimer's disease is a neurodegenerative disease that results in the loss of brain cells and their connections. Signs of the disease usually become evident after 65 years of age, initially as a loss of short-term memory for events that occurred a few minutes earlier. Over the disease's time course of two to 20 years, cognitive impairment expands to involve long-term memory and language skills. Eventually, all aspects of intellect are lost. Alzheimer's disease currently affects 4.5 million Americans. By the middle of this century, as many as 14 million of today's baby boomers could have Alzheimer's.
The Byrd Alzheimer's Research Institute is a state-wide center for Alzheimer's research, based at the University of South Florida in Tampa. The National Institutes of Health recently designated the Byrd Alzheimer's Institute and USF as Florida's Alzheimer's Disease Research Center. Information on the study and helpful information on treatment and prevention of Alzheimer's disease can be found at: www.byrdinstitute.org.
Other key members of the team are Dr. David Costa, Jennifer Cracchiolo, and Dr. Gary Arendash, also of the Byrd Institute, the Florida ADRC, and the University of South Florida.
For interviews with Huntington Potter, Ph.D., please contact:
Jennifer Whelihan
813-866-1610 ext. 4115
jwhelihan@byrdinstitute.org
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Click here to read the final published version. (PDF)
For more information on the study or on Alzheimer's disease, please visit: www.byrdinstitute.org.