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 Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign

nachricht Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn

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: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>