Featured Research

from universities, journals, and other organizations

Turning 'bad' fat into good: A new candidate pathway for treating visceral obesity

Date:
May 6, 2012
Source:
Brigham and Women's Hospital
Summary:
Brown seems to be the color of choice when it comes to the types of fat cells in our bodies. Brown fat expends energy, while its counterpart, white fat stores it. Now a team of researchers has essentially made white fat take on characteristics of brown fat. Their findings put medical science a step closer in the race to develop novel anti-obesity therapies.

In the absence of Aldh1a1, visceral fat (far left) begins producing proteins that characterize brown fat (far right), including UCP1, which releases heat and appears brown in these cells (see arrow). The changes in visceral fat are more pronounced that subcutaneous fat (middle panel).
Credit: Image courtesy of Brigham and Women's Hospital

Brown seems to be the color of choice when it comes to the types of fat cells in our bodies. Brown fat expends energy, while its counterpart, white fat stores it. The danger in white fat cells, along with the increased risk for diabetes and heart disease it poses, seems especially linked to visceral fat. Visceral fat is the build-up of fat around the organs in the belly.

So in the battle against obesity, brown fat appears to be our friend and white fat our foe.

Now a team of researchers led by Jorge Plutzky, MD, director of The Vascular Disease Prevention Program at Brigham and Women's Hospital (BWH) and Harvard Medical School has discovered a way to turn foe to friend.

By manipulating the metabolic pathways in the body responsible for converting vitamin A-or retinol-into retinoic acid, Plutzky and his colleagues have essentially made white fat take on characteristics of brown fat. Their findings put medical science a step closer in the race to develop novel anti-obesity therapies.

The study will be published online on May 6, 2012 in Nature Medicine.

Retinoids, which are molecules derived from vitamin A metabolism, are responsible for many biological functions. One such function is the control of fat cell development and actions. A key step in retinoid metabolism occurs with help from an enzyme called retinaldehyde dehydrogenase 1, or Aldh1a1. The researchers saw that in humans and mice, Aldh1a1 is abundant in white fat cells, especially in the more dangerous visceral fat (sometimes referred to as abdominal fat or belly fat).

When Aldh1a1 was inhibited in white fat cells, those cells began acting like brown fat cells. One of the defining characteristics of brown fat is its ability to release energy as heat. Mice with either deficiency or inhibition of Aldh1a1 become protected against exposure to cold. The researchers saw this classic indicator of brown fat and its ability to generate heat by oxidizing fat (a chemical reaction involving oxygen) in their research.

Especially exciting for the prospects of targeting Aldh1a1 for therapeutic benefit, the researchers found that knocking down expression of the Aldh1a1 gene by injecting antisense molecules into mice made fat by diet resulted in less visceral fat, less weight gain, lower glucose levels, and protection against cold exposure as compared to control mice.

"Brown fat, and mechanisms that might allow white fat to take on brown fat characteristics, has been receiving increasing attention as a possible way to treat obesity and its complications," said Plutzky. "Although more work is needed, we can add specific aspects of retinoid metabolism to those factors that appear involved in determining white versus brown fat."

According to the Centers for Disease Control and Prevention, more than one-third of adults in the United States are obese. Current methods to reduce obesity include exercise, dietary therapy, medications and surgery.

This research was supported by the National Institutes of Health grants HL048743, AR054604-03S1, 5P30DK057521-12; Mary K. Iacocca Professorship; National Institute of Diabetes and Digestive and Kidney Diseases; and Austrian Science Fund.


Story Source:

The above story is based on materials provided by Brigham and Women's Hospital. Note: Materials may be edited for content and length.


Journal Reference:

  1. Florian W Kiefer, Cecile Vernochet, Patrick O'Brien, Steffen Spoerl, Jonathan D Brown, Shriram Nallamshetty, Maximilian Zeyda, Thomas M Stulnig, David E Cohen, C Ronald Kahn, Jorge Plutzky. Retinaldehyde dehydrogenase 1 regulates a thermogenic program in white adipose tissue. Nature Medicine, 2012; DOI: 10.1038/nm.2757

Cite This Page:

Brigham and Women's Hospital. "Turning 'bad' fat into good: A new candidate pathway for treating visceral obesity." ScienceDaily. ScienceDaily, 6 May 2012. <www.sciencedaily.com/releases/2012/05/120506160113.htm>.
Brigham and Women's Hospital. (2012, May 6). Turning 'bad' fat into good: A new candidate pathway for treating visceral obesity. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2012/05/120506160113.htm
Brigham and Women's Hospital. "Turning 'bad' fat into good: A new candidate pathway for treating visceral obesity." ScienceDaily. www.sciencedaily.com/releases/2012/05/120506160113.htm (accessed July 24, 2014).

Share This




More Health & Medicine News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com
Condemned Man's US Execution Takes Nearly Two Hours

Condemned Man's US Execution Takes Nearly Two Hours

AFP (July 24, 2014) America's death penalty debate raged Thursday after it took nearly two hours for Arizona to execute a prisoner who lost a Supreme Court battle challenging the experimental lethal drug cocktail. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com
Can Watching TV Make You Feel Like A Failure?

Can Watching TV Make You Feel Like A Failure?

Newsy (July 24, 2014) A study by German researchers claims watching TV while you're stressed out can make you feel guilty and like a failure. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins