(Press-News.org) Contact information: Bonnie Prescott
bprescot@bidmc.harvard.edu
617-667-7306
Beth Israel Deaconess Medical Center
Intranasal insulin improves cognitive function in patients with type 2 diabetes
BOSTON – In recent years, the link between type 2 diabetes and dementia has become widely recognized. Older individuals with diabetes develop Alzheimer's disease at an earlier age, and are more likely to develop vascular dementia than people who do not have diabetes.
Now, a small proof-of-concept study led by investigators at Beth Israel Deaconess Medical Center (BIDMC) offers promise of a new treatment for this widespread problem. Currently published on-line in the journal Diabetes Care, the study results show that a single dose of intranasal insulin can help improve cognitive function in patients with diabetes.
"We know that diabetes accelerates brain aging," explains first author Vera Novak, MD, PhD, an investigator in the Department of Neurology at BIDMC, who conducted this research as a faculty member in BIDMC's Department of Medicine. "If we consider that there are more than 45 million people with diabetes in the U.S. alone and that older adults are the fastest growing segment of the diabetes population, we realize what an extremely serious problem we're facing."
In the brain, insulin helps to regulate signaling and connections among neurons and also regulates vascular functions. Central insulin receptors are abundant and yet are mostly dependent upon insulin transport through the blood-brain barrier. Therefore, inadequate insulin delivery may affect perfusion and cortical activity in brain regions associated with high-energy demands, such as cognitive networks.
"Previous studies had suggested that augmenting cerebral insulin may enhance cognitive function," says Novak, an Associate Professor of Neurology at Harvard Medical School. Intranasal administration delivers insulin directly to the brain, bypassing the blood-brain barrier and reaching receptors in multiple brain regions within minutes after administration.
In this pilot study, the authors tested whether similar effects would be observed in patients with diabetes. Fifteen patients with diabetes and 14 healthy older adults, average age 62, were administered a single 40-unit dose of insulin or saline in a randomized order on two subsequent days. Measurements of brain function were then made using regional perfusion and vasodilatation with 3 Tesla MRI and neuropsychological evaluation of learning and memory.
"We observed in both the healthy subjects and the patients with diabetes that there was an improvement in both verbal learning and visual-spatial learning and memory after they received the insulin," explains Novak. Through imaging tests, the investigators also learned that these improvements were dependent on the brain's vascular function.
"Our findings provide preliminary evidence that intranasal insulin administration appears safe in older adults, and does not lead to low sugar levels," says Novak. "Intranasal insulin may potentially improve learning and memory in older adults with and without diabetes, through vascular mechanisms. However, larger and longer duration studies are needed to determine whether intranasal insulin may provide long-term benefits for memory in older patients with diabetes."
###
Study coauthors include BIDMC investigators Andrew Galica and Bradley Manor; William Milberg of VA Boston Healthcare and Harvard Medical School; Medha Munshi of the Joslin Diabetes Center; Peter Novak of the University of Massachusetts Medical School; Paula Roberson of the University of Arkansas for Medical Sciences; Suzanne Craft of Wake Forest University School of Medicine and Amir Abduljalil of The Ohio State University; and Yin Hao of Peking University.
This study was funded by grants from the National Institute of Diabetes and Digestive and Kidney Diseases (5R21-DK-084463-02), the National Institute on Aging (1R01-AG-0287601-A2; R01-AG-027415); the National Institutes of Health (1KL2RR025757-04; 8KL2T^R000168-05;; 8UL1TR000170-05); Veterans Administration (B6796-C) as well as grants from the China Scholarship Council.
Beth Israel Deaconess Medical Center is a patient care, teaching and research affiliate of Harvard Medical School and currently ranks third in National Institutes of Health funding among independent hospitals nationwide.
BIDMC has a network of community partners that includes Beth Israel Deaconess Hospital-Milton, Beth Israel Deaconess Hospital-Needham, Anna Jaques Hospital, Cambridge Health Alliance, Lawrence General Hospital, Signature Health Care, Commonwealth Hematology-Oncology, Beth Israel Deaconess HealthCare, Community Care Alliance, and Atrius Health. BIDMC is also clinically affiliated with the Joslin Diabetes Center and Hebrew Senior Life and is a research partner of the Dana-Farber/Harvard Cancer Center. BIDMC is the official hospital of the Boston Red Sox. For more information, visit http://www.bidmc.org.
Intranasal insulin improves cognitive function in patients with type 2 diabetes
2013-11-14
ELSE PRESS RELEASES FROM THIS DATE:
Fantastic phonons: Blocking sound, channeling heat with 'unprecedented precision'
2013-11-14
Fantastic phonons: Blocking sound, channeling heat with 'unprecedented precision'
Imagine living on a bustling city block, but free from the noise of car horns and people on the street. The emerging field of phononics could one day make this ...
Feral cats avoid urban coyotes, are surprisingly healthy
2013-11-14
Feral cats avoid urban coyotes, are surprisingly healthy
Study suggests urban coyotes may 'protect' certain wildlife from cats
COLUMBUS, Ohio -- Cats that live outdoors in the city do their darnedest to steer clear of urban coyotes, a new study says.
The cats cause less ...
NASA sees a re-awakening of ex-Depression 30W in a different ocean
2013-11-14
NASA sees a re-awakening of ex-Depression 30W in a different ocean
The former tropical storm known as 30W that moved from the western North Pacific Ocean basin into the northern Indian Ocean appears to be ramping up for a short stint at depression status again. ...
Lifting fusion power onto an (optimized) pedestal
2013-11-14
Lifting fusion power onto an (optimized) pedestal
New insights into a fusion plasma's transport barrier promise to boost future reactor performance
In a collaborative effort, researchers in the United States and the United Kingdom have developed a new technique that ...
New antenna spreads good vibrations in fusion plasma
2013-11-14
New antenna spreads good vibrations in fusion plasma
'Shoelace Antenna' exploits naturally occurring resonant vibrations to regulate heat and particle flow through the plasma boundary in a tokamak fusion reactor
If you want to catch a firefly, any old glass jar will ...
BUSM/BMC study shows decrease in sepsis mortality rates
2013-11-14
BUSM/BMC study shows decrease in sepsis mortality rates
(Boston) – A recent study from Boston University School of Medicine (BUSM) and Boston Medical Center (BMC) shows a significant decrease in severe sepsis mortality rates over the past 20 years. Looking ...
Expert assessment: Ocean acidification may increase 170 percent this century
2013-11-14
Expert assessment: Ocean acidification may increase 170 percent this century
Substantial costs expected from coral reef loss and declines in shellfisheries; Cold water corals also at risk
In a major new international report, experts conclude ...
Lignin-feasting microbe holds promise for biofuels
2013-11-14
Lignin-feasting microbe holds promise for biofuels
Nature designed lignin, the tough woody polymer in the walls of plant cells, to bind and protect the cellulose sugars that plants use for energy. For this reason, lignin is a major challenge for those ...
Northeastern researchers have discovered a new treatment to cure MRSA infection
2013-11-14
Northeastern researchers have discovered a new treatment to cure MRSA infection
Recent work from University Distinguished Professor of Biology Kim Lewis promises to overcome one of the leading public health threats of our time. In a groundbreaking study published ...
Snow melts faster under trees than in open areas in mild climates
2013-11-14
Snow melts faster under trees than in open areas in mild climates
It's a foggy fall morning, and University of Washington researcher Susan Dickerson-Lange pokes her index finger into the damp soil beneath a canopy of second-growth conifers. The tree cover is dense here, ...