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 Fast-tracking T cell therapies with immune-mimicking biomaterials
16.01.2018 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht Dengue takes low and slow approach to replication
12.01.2018 | Duke University

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 decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

Im Focus: A thermometer for the oceans

Measurement of noble gases in Antarctic ice cores

The oceans are the largest global heat reservoir. As a result of man-made global warming, the temperature in the global climate system increases; around 90% of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Novel 3-D printing technique yields high-performance composites

16.01.2018 | Materials Sciences

New application for acoustics helps estimate marine life populations

16.01.2018 | Life Sciences

Fast-tracking T cell therapies with immune-mimicking biomaterials

16.01.2018 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>