Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mouse, stripped of a key gene, resists diabetes

03.09.2003


An engineered mouse, already known to be immune to the weight gain ramifications of a high-calorie, high-fat diet, now seems able to resist the onset of diabetes.


Professor of biochemistry and nutritional sciences James Ntambi holds two mice in his research lab and points to the mouse that is missing a SCD-1 gene and is significantly thinner than the normal mouse at right. Ntambi recently found that subracting a single gene, SCD-1, from the genome of a mouse creates an animal that can eat a rich, high-fat diet without gaining weight or risking the complications of diabetes.
Photo by: Jeff Miller
Date: August 2002



The mouse, stripped of a gene known as SCD-1, is apparently impervious to the negative effects of the type of diet that, for many people, has significant health and social consequences.

"We think this animal model may be protected against diabetes," says James Ntambi, a University of Wisconsin-Madison professor of biochemistry and Steenbock professor of nutrition, and the senior author of a report describing the remarkable mouse in this week’s (Sept. 1) online editions of the Proceedings of the National Academy of Sciences (PNAS).


The new finding is important because it provides critical genetic and biochemical clues to diet, obesity and the onset of a disease that affects as much as 6 percent of the U.S. population.

Type II diabetes, which accounts for about 90 percent of the incidence of diabetes in the United States, is a chronic disease caused by a problem in the way the body makes or uses insulin. Insulin is a hormone secreted by the pancreas that, under healthy circumstances, plays an essential role in moving glucose from blood to cells where the sugar’s energy is expended.

In many instances, obesity and diabetes go hand in hand. Between 75 and 80 percent of people with type II diabetes are obese, although the disease can also develop in lean people, especially the elderly.

The discovery of a gene that seems to exercise significant influence over both weight gain and glucose regulation promises a potentially significant window into both conditions and their relationship. The gene makes an enzyme called SCD. It affects the production of fatty acids, and because humans have SCD-1 equivalents, the new finding helps explain why some people, who may lack the gene, remain lean and diabetes free, despite a rich, fatty diet.

"We are beginning to suspect that obese individuals have increased expression of this enzyme," says Ntambi. "If you reduce expression of this enzyme, you reduce fat expression in muscle."

This new insight into the gene and its influence could herald the development of new drugs to prevent both diabetes and obesity as it may help scientists zero in on the underlying problems that lead to both conditions.

In the engineered mice, the Wisconsin team observed that muscle cells were more sensitive to insulin, enabling the cells to absorb glucose and avoid hyperglycemia. Elevated levels of glucose in the blood prompt the pancreas to produce more insulin, which tends to make cells even more resistant to the critical hormone.

"In this animal, there is increased insulin signaling or sensitivity," Ntambi explains. "When insulin binds to the cell’s insulin receptor, it triggers a cascade of events " that enables the animal to successfully regulate levels of blood sugar.

"There are lots of steps involved in the process, and in the case of type II diabetes things go wrong in some of those events," Ntambi says. "What we found in these animals is that the insulin signaling steps in muscle are all enhanced, despite low levels of insulin in plasma. We don’t see a defect yet."


The work by the Wisconsin team was funded primarily by the National Institutes of Health and in part by a grant from Xenon Genetics, Inc.

In addition to Ntambi, co-authors of the PNAS report include Shaikh Mizanoor Rahman, Agnieszka Dobrzyn, Pawel Dobrzyn, Seong-Ho Lee and Makoto Miyazaki.

- Terry Devitt (608) 262-8282, trdevitt@wisc.edu

James Ntambi | EurekAlert!
Further information:
http://www.wisc.edu/

More articles from Health and Medicine:

nachricht Spanish scientists create a 3-D bioprinter to print human skin
24.01.2017 | Carlos III University of Madrid

nachricht Tracking movement of immune cells identifies key first steps in inflammatory arthritis
23.01.2017 | Massachusetts General Hospital

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: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

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...

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

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>