- HMS Community Values
- Introduction to Clinical Research Training
- Letter from the Chairman
- Medical Education
- Application Form and Instructions
- United Kingdom Clinical Scholars Research Training
- Award Listing
- Vanderbilt Hall
- Award Summaries
- Financial Aid
- Spring Preview
- Frequently Asked Questions
- Office of the Registrar
- Award Recipients
- Campus Planning and Facilities
- Ombuds Office
- Research Administration Contacts
- Committee on Microbiological Safety
- Contact Us
- Human Resources
- The Academy
- Office for Academic and Clinical Affairs
- Joint Committee on the Status of Women
- Global Health Research Core
- Global Clinical Scholars Research Training Program
- HMA Standing Committee on Animals
- Office of Research Compliance
- Harvard Medical School Event Calendar
- Office of Diversity RIA Program
- The Dean's Perspective
- Department of Pathology
- Harvard Mahoney Neuroscience Institute
- OHRA Home
- Office of Research Subject Protection
- Alumni Association
- Cancer Biology & Therapeutics Program
- Celiac Program
- Department of Medicine
- HMS Information Technology
- HMS TransMed Program
- Introduction to the Practice of American Medicine
- Office of Communications & External Relations
- Big Data In Healthcare
- Institutional Planning and Policy
- Master of Medical Sciences In Clinical Investigation
- Office of Global Education
- Portugal Clinical Scholars Research Training Program
- Safety Quality Informatics and Leadership
- South American Clinical Research Training Program | SACRT
- Southeast Asia Leadership Program
- Shenzhen-HMS Initiative in International Education
- Contact @HMS
- Office of Global Education
- Human Resources
- Jobs @ HMS
- Dental Medicine
- Harvard University
- Contact us
Environment Counts, Alzheimer’s Research Suggests
Previous studies have shown that exercise, an active mind and social interaction may help delay the onset of dementia in Alzheimer’s patients, but now a new study indicates environment also plays a key role.
The study, led by Dennis Selkoe, Vincent and Stella Coates Professor of Neurologic Diseases in the HMS Department of Neurology and Brigham and Women’s Hospital, provides specific, preclinical evidence supporting the concept that prolonged and intensive stimulation by an enriched environment—especially regular exposure to new activities—may have beneficial effects in delaying one of the key negative factors in Alzheimer’s disease.
“This part of our work suggests that prolonged exposure to a richer, more novel environment beginning even in middle age might help protect the hippocampus from the bad effects of amyloid beta, which builds up to toxic levels in 100 percent of Alzheimer’s patients,” said Selkoe
Researchers used a wild-type mouse model to evaluate how the environment might affect the progression of Alzheimer’s. Unlike other preclinical models used in Alzheimer’s research, wild-type mice tend to more closely mimic the scenario of disease development in humans under normal environmental conditions, rather than in individuals with a strong genetic predisposition to the disease.
Alzheimer’s disease occurs when amyloid beta protein accumulates and forms so-called senile plaques in the brain. This protein accumulation can block nerve cells in the brain from properly communicating with one another. This may lead to a gradual erosion of an individual’s mental processes, such as memory, attention and the ability to learn, understand and process information.
Selkoe and his team found that prolonged exposure to an enriched environment activated certain adrenalin-related brain receptors. The activity triggered a signaling pathway that prevented the amyloid beta protein from weakening the communication between nerve cells in the hippocampus, which plays an important role in both short- and long-term memory.
The ability of an enriched, novel environment to prevent amyloid beta protein from affecting the signaling strength and communication between nerve cells was seen in both young and middle-aged wild-type mice.
Moreover, the scientists found that exposing the brain to novel activities in particular provided greater protection against Alzheimer’s disease than did just aerobic exercise. According to the researchers, this observation may be due to stimulation that occurred not only physically, but also mentally, when the mice moved quickly from one novel object to another.
“This work helps provide a molecular mechanism for why a richer environment can help lessen the memory-eroding effects of the buildup of amyloid beta protein with age,” said Selkoe. “They point to basic scientific reasons for the apparent lessening of [Alzheimer’s disease] risk in people with cognitively richer and more complex experiences during life.”
This work was supported by the National Institutes of Health, the Massachusetts Alzheimer’s Disease Research Center, the Massachusetts General Hospital Neurology Clinical Trials Units, and the Harvard NeuroDiscovery Center.
Adapted from Brigham and Women’s Hospital news release.
Stay informed via email on the latest news, research, and
media from Harvard Medical School.