Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hopkins researchers discover potential new approach to treating diabetes

12.06.2006
Scientists at Johns Hopkins have uncovered a surprising and novel way of lowering blood sugar levels in mice by manipulating the release of sugar by liver cells. The results, published in the June issue of Cell Metabolism, have implications for treating conditions like diabetes.

The discovery by researchers in Hopkins' Institute of Basic Biomedical Sciences and McKusick-Nathans Institute for Genetic Medicine reveals that a protein called GCN5 is critical for controlling a domino-like cascade of molecular events that lead to the release of sugar from liver cells into the bloodstream. Understanding the role of GCN5 in maintaining blood sugar levels is leading to a clearer picture of how the body uses sugar and other nutrients to make, store and spend energy.

"Understanding the ways that energy production and use are controlled is crucial to developing new drugs and therapies," says the report's senior author, Pere Puigserver, Ph.D., an assistant professor of cell biology at Hopkins.

The inability to properly regulate blood sugar levels leads to conditions like obesity and diabetes. Both type 1 and type 2 diabetes cause blood sugar levels to stay too high, which can lead to complications like blindness, kidney failure and nerve damage.

"Diabetes is a really big problem, even when patients are given insulin and stay on strict diets," says Carles Lerin, Ph.D., a postdoctoral fellow in cell biology at Hopkins and an author of the report. "In the absence of a cure for the disease, we are really trying to focus on finding better treatment because currently available methods just don't work that efficiently," he says.

The body keeps blood sugar – known as glucose – within a narrow range. Extra glucose floating through the bloodstream, which is common after eating a meal, is captured and kept in the liver. When blood glucose runs low, the liver releases its stores back into the bloodstream. When those reserves are tapped out, liver cells turn on genes to make more glucose to fuel the body.

The research team found that GCN5 chemically alters another protein called PGC-1alpha that normally turns on a set of genes to manufacture enzymes required for glucose release. When GCN5 is fully functional in liver cells, this cascade is turned off and glucose is not released from those cells. Removal of functional GCN5 from liver cells restores the cells' ability to release glucose.

The researchers showed that GCN5 alters its target, sabotaging it by adding a chemical tag called an acetyl group. By using molecules that glow fluorescently, the researchers saw under high-power microscopes that GCN5 carries its tagged target to a different location in the cell's nucleus – sequestering it away from the genes it's normally meant to turn on.

"GCN5 has been generally shown to turn on genes. No one knew that GCN5 could be used to turn off pathways" says Lerin. "It was a bit of a surprise."

When the researchers put GCN5 into live mice, they found that it can in fact decrease blood glucose levels. Liver cells in mice that were given no food for 16 hours actively release glucose into the bloodstream. Introducing GCN5 into their livers, however, causes blood glucose levels in these mice to be reduced.

"These results show that changing GCN5 is sufficient to control the sugar balance in mice," says Puigserver. "Therefore, GCN5 has the potential to be a target for therapeutic drug design in the future."

Audrey Huang | EurekAlert!
Further information:
http://www.jhmi.edu

More articles from Health and Medicine:

nachricht Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine

nachricht NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)

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: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Previous evidence of water on mars now identified as grainflows

21.11.2017 | Physics and Astronomy

NASA's James Webb Space Telescope completes final cryogenic testing

21.11.2017 | Physics and Astronomy

New catalyst controls activation of a carbon-hydrogen bond

21.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>