Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Estrogen’s Effects on Fat Depends on Where It’s Located

30.07.2013
Article published in the American Journal of Physiology: Endocrinology and Metabolism

Women have long bemoaned the fact that they tend to store more fat than men, particularly after menopause. Although it’s well established that estrogen, the primary sex hormone present during women’s childbearing years, is responsible for this effect, exactly how estrogen exerts this influence has been unknown.

Previous research has shown that body fat both absorbs estrogen and other sex hormones circulating in the blood as well as produces its own sex hormones, though researchers have been unsure what role that plays in fat accumulation. Also not completely understood is why women tend to accumulate fat in the stereotypical “pear” shape, with more fat in the buttocks and thighs—a shape that’s thought to be healthier than men’s stereotypical “apple” shape, with more fat around the belly.

Gathering clues to answer these questions, Kathleen M. Gavin and her colleagues at East Carolina University examined how estrogen locally affects fat accumulation in these key areas by slowly infusing the hormone into the buttocks and belly in overweight women while also giving them drugs or having them exercise to speed up fat breakdown. They found that estrogen’s effects on these fat deposits was highly dependent on the deposits’ specific location and the fat-burning interventions themselves.

The article is entitled “Estradiol Effects on Subcutaneous Adipose Tissue Lipolysis in Premenopausal Women are Adipose Tissue Depot Specific and Treatment Dependent” (http://bit.ly/1aKKegY). It appears in the June edition of the American Journal of Physiology: Endocrinology and Metabolism, published by the American Physiological Society.

Methodology

Gavin and her colleagues recruited 17 overweight-to-obese premenopausal women, all between the ages of 18 and 44 years old. After an initial visit to the lab to gather a variety of information on each study participant, including weight, height, percent fat and lean mass, and VO2 max (a measure of physical fitness), the researchers subjected each participant to a variety of interventions meant to speed up lipolysis, or fat breakdown/mobilization. Through probes inserted directly in the fat of the participants’ buttocks and abdomen, the researchers slowly infused two drugs, either individually or together, that encourage lipolysis. They also had participants perform a bout of exercise at an intensity similar to a standard exercise session. Such “submaximal” exercise is known to optimally break down fat.

Participants performed this exercise both by itself and while the drugs were being infused. To test the effects of estrogen, the researchers also performed each of these conditions while estrogen was also being slowly infused into participants’ fat deposits. To measure fat breakdown, the researchers used a technique called microdialysis to look for a marker (glycerol) left behind when stored fat is broken down for eventual production of energy.

Results

The researchers found that estrogen’s effects differed tremendously depending on the fat- mobilizing interventions themselves and where the fat deposit was located. For example, estrogen blunted fat breakdown in the abdomen if it was infused while a particular fat-mobilization drug called isoproterenol was also being infused, but it didn’t have this effect in the buttocks. When a second fat mobilizing drug was given along with the first while participants were at rest, fat breakdown didn’t change any further. However, when both drugs were injected together during exercise or when the volunteers exercised without the drugs, fat breakdown increased in the abdomen, but less so in the buttocks.

Importance of the Findings

These results suggest that estrogen has different effects within fat tissue depending on its location. Together, these effects could help maintain premenopausal women’s “pear” shape even in the face of exercise or other signals the body receives to break down fat. They could also help generate some new ideas on how estrogen in fat may influence why postmenopausal women tend to accumulate more fat in the abdomen.

The authors suggest that more research is necessary to better understand the mechanisms behind how and why estrogen acts in these differential ways.

Study Team

In addition to Kathleen M. Gavin, the study team also includes Elizabeth E. Cooper, Dustin K. Raymer, and Robert C. Hickner, all of East Carolina University.

NOTE TO EDITORS: To schedule an interview with a member of the research team, please contact Donna Krupa at dkrupa@the-aps.org, @Phyziochick, or 301.634.7209. The article is available online at http://bit.ly/1aKKegY.

Physiology is the study of how molecules, cells, tissues, and organs function in health and disease. Established in 1887, the American Physiological Society (APS) was the first US society in the biomedical sciences field. The Society represents more than 11,000 members and publishes 14 peer-reviewed journals with a worldwide readership.

Donna Krupa | Newswise
Further information:
http://www.the-aps.org

More articles from Health and Medicine:

nachricht TSRI researchers develop new method to 'fingerprint' HIV
29.03.2017 | Scripps Research Institute

nachricht Periodic ventilation keeps more pollen out than tilted-open windows
29.03.2017 | Technische Universität München

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>