Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Joslin study finds clue to birth defects in babies of mothers with diabetes

17.10.2011
Stimulation of metabolism-sensing enzyme that can regulate crucial gene explains how free radicals generated during maternal hyperglycemia cause malformation of the neural tube

In a paper published today in Diabetologia, a team at Joslin Diabetes Center, headed by Mary R. Loeken, PhD, has identified the enzyme AMP kinase (AMPK) as key to the molecular mechanism that significantly increases the risk of neural tube defects such as spina bifida and some heart defects among babies born to women with diabetes.

Even if women with diabetes -- either type 1 or type 2 -- work vigilantly to control their blood sugar levels around the time of conception, the risk of a defect is still twice that of the general population. This finding could lead to strategies to interfere with the mechanism and reduce the chances of such birth defects occurring.

Previous studies published by Loeken's lab showed that maternal hyperglycemia (high blood sugar) causes oxidative stress in the embryo, and inhibits expression of the Pax3 gene. Pax3 is essential to the formation of the neural tube, which in the embryo is the precursor to the brain and spinal cord. Oxidative stress results when oxidized molecules - called free radicals - are created faster than they can be eliminated.

However, Loeken said, it was not known how the cells that express Pax3 could sense the oxidative stress and why oxidative stress, which occurs throughout the embryo, only damages selective structures such as the neural tube.

In the paper published today, Loeken's team identifies the key to the process as AMP kinase, which is activated by oxidative stress and was found to signal the cell nucleus to block the expression of Pax3.

"The stimulation of a metabolism-sensing enzyme that can regulate specific genes explains how oxidative stress, which is generated throughout the embryo during maternal hyperglycemia, causes malformation of specific embryo structures," Loeken said.

"We now know that we must do whatever we can to prevent AMPK from being stimulated," said Loeken, who is a research investigator in Joslin's Section on Islet Cell and Regenerative Biology.

Trying to keep the mother's blood glucose levels under control is currently the only way to do that, she noted. "That's the best we can do right now," she said. But armed with the findings of this study, she noted, other researchers may be able to come up with drugs or other strategies to inhibit AMPK activity,

Dr. Loeken added, however, that formulating a strategy could be tricky because it is not known if interfering with AMPK activity -- while a good thing in preventing neural tube birth defects -- might also have negative effects on the embryo.

In their study Loeken and her group, including Yichao Wu, Marta Viana, and Shoba Thirumangalathu, used mice and cell lines to test their hypothesis that AMPK might be stimulated in the embryo and that stimulation of AMPK was responsible for blocking Pax3 expression and causing neural tube defects in response to high glucose.

"We found in this study that AMPK is stimulated in embryo by both high glucose and oxidative stress," Loeken said.

The study used interventions including a drug that activates AMPK and another that blocks it. The paper showed that a drug that increased AMPK activity mimics the effects of oxidative stress to inhibit expression of Pax3, thus inducing neural tube defects.

This research was supported by a grant from the National Institutes of Health.

About Joslin Diabetes Center

Joslin Diabetes Center is the world's preeminent diabetes research and clinical care organization. Joslin is dedicated to ensuring that people with diabetes live long, healthy lives and offers real hope and progress toward diabetes prevention and a cure. Joslin is an independent, nonprofit institution affiliated with Harvard Medical School. For more information about Joslin, visit http://www.joslin.org. Keep up with Joslin research and clinical news at Inside Joslin at http://www.joslin.org/news/inside_joslin.html, Become a fan of Joslin on Facebook at http://www.facebook.com/joslindiabetes and follow Joslin on Twitter at http://www.twitter.com/joslindiabetes

Jeffrey Bright | EurekAlert!
Further information:
http://www.joslin.org

More articles from Studies and Analyses:

nachricht Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>