Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fitness counteracts cognitive decline from hormone-replacement therapy

25.01.2006


Women pondering hormone-replacement therapy also should consider regular exercise. A new study at the University of Illinois at Urbana-Champaign suggests that being physically fit offsets cognitive declines attributed to long-term therapy.

"This study not only tells us that there is a benefit to being highly fit, it pinpoints where in the brain it matters for postmenopausal women who have been using the two strategies," said lead author Kirk I. Erickson, a postdoctoral researcher at the Beckman Institute for Advanced Science and Technology at Illinois.

The study appeared online this month in advance of regular publication in the journal Neurobiology of Aging. By using magnetic resonance imaging and voxel-based morphometry (VBM), researchers documented the combined effects on specific areas of the brain based on fitness of short- and long-term users of hormone therapy.



Researchers also looked at how well 54 postmenopausal women performed on a computerized version of the Wisconsin Card Sort Test, in which constantly changing rules challenge memory, inhibition and task-switching abilities known as executive functions. The women were divided into groups based on use or non-use and duration of hormone therapy and existing fitness levels.

"We found that higher fitness levels enhance the effects of shorter durations of hormone treatment and offset the declines associated with long-term use," said Arthur F. Kramer, a Beckman researcher and psychology professor. "It may be that a combination of HRT and exercise boosts both cognition and brain structure of older women."

Participants ranged in age from 58 to 80, with a mean age of 70. Hormone status and duration of use were assessed based on their self-reports, and aerobic fitness was measured by monitoring respiration, heart rate and blood pressure during a treadmill test.

MRI images of the participants’ brains were taken, segmented into 3-D maps and analyzed by VBM, which allows for high spatial resolution of the volume of gray and white matter. The women also were screened for duration of hormone use, aerobic fitness levels, age, education, socioeconomic status, age at menopause and for dementia.

VBM analysis revealed that four regions of gray matter -- left and right prefrontal cortex, left parahippocampal gyrus and left subgenual cortex -- varied with duration of hormone treatment. Longer hormone usage resulted in significantly less tissue volume in these areas. However, higher fitness scores were tied to greater tissue volume.

While there were no significant effects of the interaction of hormone duration and fitness on white matter in general, higher fitness levels were tied to greater prefrontal white matter regions and in the genu of the corpus callosum, a key area that interconnects frontal areas of the brain.

"Critically, the tissue volume measures in all four gray matter regions revealed that high fitness levels were associated with a more modest decline in regional brain volume than low fitness levels with increasing durations of hormone therapy," the researchers wrote. "High fitness levels also were associated with a significant sparing of the neural tissue of women not receiving hormone replacement therapy."

Durations of therapy of less than 10 years showed enhanced tissue volume compared with all other groups, and the decline in tissue volume only began after 11 to 15 years of hormone-replacement therapy.

Erickson and Kramer noted that their findings in women were in line with previous animal studies that have found that estrogen and fitness have similar mechanisms in the brain. Estrogen and fitness both stimulate brain-derived neurotropic factor, a molecule tied to the production of capillaries, plasticity and neurons.

These preliminary findings are based on only a small sampling of women and need to be considered in a much broader clinical setting, Kramer said. However, the findings mirror similar studies in his lab that are continuing to show the benefits of physical fitness in older people.

Co-authors with Erickson and Kramer were Stanley J. Colcombe, a research scientist at the Beckman Institute; Paige E. Scalf, a postdoctoral researcher in Kramer’s lab; Edward McAuley, a Beckman researcher and professor of kinesiology and psychology; McAuley’s former doctoral student Steriani Elavsky; and Donna L. Korol, professor of psychology.

Jim Barlow | EurekAlert!
Further information:
http://www.uiuc.edu

More articles from Health and Medicine:

nachricht Study tracks inner workings of the brain with new biosensor
16.08.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht Foods of the future
15.08.2018 | Georg-August-Universität Göttingen

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

Smallest transistor worldwide switches current with a single atom in solid electrolyte

17.08.2018 | Physics and Astronomy

Robots as Tools and Partners in Rehabilitation

17.08.2018 | Information Technology

Climate Impact Research in Hannover: Small Plants against Large Waves

17.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>