Featured Research

from universities, journals, and other organizations

Novel role for protein linked to obesity and development of type 2 diabetes identified

Date:
December 17, 2012
Source:
UT Southwestern Medical Center
Summary:
Researchers have taken another step toward better understanding the metabolic functions of obesity and its connection to type 2 diabetes.

By successfully manipulating a specific protein, researchers like Drs. Phillip Scherer and Christine Kusminski have made headway in unlocking obesity's metabolic functioning and its connection to type 2 diabetes.
Credit: Image courtesy of UT Southwestern Medical Center

Researchers at UT Southwestern Medical Center have taken another step toward better understanding the metabolic functions of obesity and its connection to type 2 diabetes.

Dr. Philipp Scherer, Director of the Touchstone Center for Diabetes Research at UT Southwestern, led a group of researchers in a recent multicenter study published in Nature Medicine that successfully identified ways to manipulate the protein mitoNEET. This is the first time the protein has been effectively altered to expand fat tissue in a way that allows subjects -- in this case, mice -- to remain metabolically healthy.

MitoNEET is a key component of a cell's mitochondrion, which serves as the cell's energy powerhouse. When the levels of MitoNEET protein were elevated inside the fat cells of rodents, more fat was stored in the adipose tissue, thereby keeping toxic lipids away from other types of cells. This sequestration resulted in extremely obese yet metabolically healthy mice that displayed no signs of type 2 diabetes. In contrast, when MitoNEET levels were decreased, the mice became lean but unhealthy, and developed pre-diabetic conditions such as failure to metabolize glucose properly.

"The manipulation of mitochondrial activity in fat tissue is a very powerful approach to control how much excess energy we store in our bodies and where we store it. We have heretofore underestimated the importance of mitochondrial pathways in our fat cells and their influence on how we manage our weight," said Dr. Scherer, senior author of the three-year study and Professor of Internal Medicine and Cell Biology at UTSW.

The body stores fat in the white adipose tissue, and, ideally, individuals burn any excess calories through exercise and a healthy diet. The current research findings suggest that manipulating components of mitochondria in fat cells can be an effective way to funnel excess calories into "good" locations. This storage then thwarts their negative effect on other internal organs like the liver in which excess fat accumulation is toxic.

The obese mice in this study weighed 120 to 130 grams (4.23 to 4.58 ounces), whereas a normal adult mouse weighs 25 to 30 grams (.88 to 1.06 ounces). This difference is the equivalent of a 150-pound person increasing his or her weight to 700 pounds.

The researchers were careful to clarify that the findings were not meant to encourage obesity, even though the obese mice were considered metabolically healthy. The study instead provides a clearer understanding of the mitochondrion's importance to the metabolic dysfunction -- that is characteristic of obese patients and those with type 2 diabetes.

"These results taught us a great deal about how fat cells sense, store, and burn energy," said Dr. Christine Kusminski, a postdoctoral researcher in Internal Medicine who served as the study's first author. "By learning more about the underlying mechanisms, we hope to develop ways to target these pathways for future drug development."

The researchers now hope to translate these findings into a clinical setting. The staff of the Touchstone Center is devoted to the study of cells and tissues that either contribute to or are affected by diabetes and related diseases, including the physiology of adipose tissue.

Other UT Southwestern researchers involved in the study were Dr. William L. Holland, Instructor in Internal Medicine; Dr. Kai Sun, Assistant Instructor in Internal Medicine; Dr. Jiyoung Park, Assistant Instructor in Internal Medicine; and Stephen B. Spurgin, a medical student. Scientists from the Albert Einstein College of Medicine, the University of Utah School of Medicine, and Merck Research Laboratories also contributed.

The investigation was funded by support from the National Institutes of Health, the American Heart Association, and fellowships from the Juvenile Diabetes Research Foundation and the Department of Defense.


Story Source:

The above story is based on materials provided by UT Southwestern Medical Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christine M Kusminski, William L Holland, Kai Sun, Jiyoung Park, Stephen B Spurgin, Ying Lin, G Roger Askew, Judith A Simcox, Don A McClain, Cai Li, Philipp E Scherer. MitoNEET-driven alterations in adipocyte mitochondrial activity reveal a crucial adaptive process that preserves insulin sensitivity in obesity. Nature Medicine, 2012; 18 (10): 1539 DOI: 10.1038/nm.2899

Cite This Page:

UT Southwestern Medical Center. "Novel role for protein linked to obesity and development of type 2 diabetes identified." ScienceDaily. ScienceDaily, 17 December 2012. <www.sciencedaily.com/releases/2012/12/121217140432.htm>.
UT Southwestern Medical Center. (2012, December 17). Novel role for protein linked to obesity and development of type 2 diabetes identified. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2012/12/121217140432.htm
UT Southwestern Medical Center. "Novel role for protein linked to obesity and development of type 2 diabetes identified." ScienceDaily. www.sciencedaily.com/releases/2012/12/121217140432.htm (accessed April 21, 2014).

Share This



More Health & Medicine News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. 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