Featured Research

from universities, journals, and other organizations

UT Southwestern Researchers Find Leptin Turns Fat-storing Cells Into Fat-burning Cells

Date:
February 10, 2004
Source:
University Of Texas Southwestern Medical Center At Dallas
Summary:
Increasing leptin, a protein involved in regulating body weight, in laboratory animals transforms fat-storing cells into unique fat-burning cells, researchers at UT Southwestern Medical Center at Dallas report. They speculate that these findings could provide "a quick and safe solution" to the obesity problem in humans.

DALLAS – Feb. 9, 2004 – Increasing leptin, a protein involved in regulating body weight, in laboratory animals transforms fat-storing cells into unique fat-burning cells, researchers at UT Southwestern Medical Center at Dallas report. They speculate that these findings could provide "a quick and safe solution" to the obesity problem in humans.

Related Articles


Researchers attribute the change in the cell's structure and function in rats – from fat storing to fat-burning – to a massive increase in the action of mitochondria, the principal energy source of the cell. The increase in mitochondria, which also led to substantial weight loss in the rats, was found two weeks after researchers injected the leptin gene.

Findings from the study will appear in an upcoming issue of the Proceedings of the National Academy of Sciences and are currently available online.

"This is the first careful examination of the fat cells after leptin therapy," said Dr. Roger Unger, director of the Touchstone Center for Diabetes Research at UT Southwestern, a physician at the Dallas Veterans Affairs Medical Center and the study's senior author. "The structure of the cells changed from the normal appearance of a fat cell to a very novel cell that's really never been seen before. There's no precedent for a cell that appears like this.

"The ability to convert fat cells into fat-burning cells may suggest novel therapeutic strategies for obesity."

Dr. Unger and his collaborators began working on this research in 1996. During the initial phase of the study, Dr. Unger observed that the fat had disappeared in the fat cells, but at that time the researchers could only guess why.

"We predicted this in 1996, but until we showed the increase in mitochondria there was not any proof of what was happening, but there were many clues that the fat was being burned inside the cell," Dr. Unger said.

Collaborating with researchers at the University of Geneva Medical School, who conducted morphological tests to analyze the form and structure of the cells, the scientists found in the current study that instead of containing fat, the cells were crowded with mitochondria.

Researchers examined laboratory animals weighing between 280 grams (a little more than half a pound) and 300 grams. Some of the study subjects received an intravenous injection of the leptin gene, which was expressed in and produced by the liver; leptin level rose 50 times greater than normal in rats after two to four days before tapering off. The remaining laboratory animals followed a restricted diet.

Animals receiving the injection experienced a rapid and profound loss of fat compared to the animals that followed a restricted diet. "After 14 days, rats receiving leptin injections plummeted on average from 280 to 207 grams," Dr. Unger said, or about 26 percent of total body weight.

While the rats receiving the leptin injections were healthy, active and had a decreased appetite, the animals that followed a restricted diet were constantly searching for food and experienced reduced physical activity.

The animals fed a restricted diet also gained back their weight faster than animals receiving the leptin injections.

Under normal circumstances leptin produced by fat cells does not interfere with the accumulation of surplus fat, but leptin secreted by the liver does interfere with the fat and actually causes the surplus to burn up, Dr. Unger said.

"We would like to break down the normal defense system against leptin produced in the fat cell. If we could disable or bypass this system and transform fat (storing) cells into fat-burning cells, then we may be a step closer to solving the obesity epidemic."

###

Other UT Southwestern researchers who contributed to the study were Dr. William Cook, a postdoctoral researcher in surgery; Dr. Byung-Hyun Park, a postdoctoral researcher in internal medicine; and Dr. May-Yun Wang, an instructor of internal medicine.

The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases and the Swiss National Science Foundation.


Story Source:

The above story is based on materials provided by University Of Texas Southwestern Medical Center At Dallas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas Southwestern Medical Center At Dallas. "UT Southwestern Researchers Find Leptin Turns Fat-storing Cells Into Fat-burning Cells." ScienceDaily. ScienceDaily, 10 February 2004. <www.sciencedaily.com/releases/2004/02/040210080157.htm>.
University Of Texas Southwestern Medical Center At Dallas. (2004, February 10). UT Southwestern Researchers Find Leptin Turns Fat-storing Cells Into Fat-burning Cells. ScienceDaily. Retrieved November 26, 2014 from www.sciencedaily.com/releases/2004/02/040210080157.htm
University Of Texas Southwestern Medical Center At Dallas. "UT Southwestern Researchers Find Leptin Turns Fat-storing Cells Into Fat-burning Cells." ScienceDaily. www.sciencedaily.com/releases/2004/02/040210080157.htm (accessed November 26, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Wednesday, November 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pet Dogs to Be Used in Anti-Ageing Trial

Pet Dogs to Be Used in Anti-Ageing Trial

Reuters - Innovations Video Online (Nov. 26, 2014) Researchers in the United States are preparing to discover whether a drug commonly used in human organ transplants can extend the lifespan and health quality of pet dogs. Video provided by Reuters
Powered by NewsLook.com
From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

From Popcorn To Vending Snacks: FDA Ups Calorie Count Rules

Newsy (Nov. 25, 2014) The US FDA is announcing new calorie rules on Tuesday that will require everywhere from theaters to vending machines to include calorie counts. Video provided by Newsy
Powered by NewsLook.com
Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Daily Serving Of Yogurt Could Reduce Risk Of Type 2 Diabetes

Newsy (Nov. 25, 2014) Need another reason to eat yogurt every day? Researchers now say it could reduce a person's risk of developing type 2 diabetes. Video provided by Newsy
Powered by NewsLook.com
Madagascar Working to Contain Plague Outbreak

Madagascar Working to Contain Plague Outbreak

AFP (Nov. 24, 2014) Madagascar said Monday it is trying to contain an outbreak of plague -- similar to the Black Death that swept Medieval Europe -- that has killed 40 people and is spreading to the capital Antananarivo. Duration: 00:42 Video provided by AFP
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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