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 New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

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: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>