Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

When the stress brake fails

21.03.2011
First discovered ten years ago, it is now the subject of new findings relating to its function: the protein SPRED2 inhibits the hormonal stress response in the body. Whether it also plays a role in the development of illnesses has yet to be established.

SPRED2: This protein is found in humans and other mammals. Among those who discovered it is a team of scientists from the University of Würzburg led by Kai Schuh. The professor is researching the function that this protein performs. In this area, he and his doctoral student Melanie Ullrich as well as other colleagues from Würzburg, Ulm, and Stockholm have now made new findings that are reported in the Journal of Biological Chemistry.

Insights into the function of the protein were gained by the scientists using mice that lack the SPRED2 gene and are therefore unable to create the protein. These animals demonstrate unusual behavior: they drink twice as much as normal mice and scratch themselves extremely often, such as behind the ears.

Abnormal hormonal states

Why this abnormal behavior? To clarify this, the researchers from the University of Würzburg’s Institute of Physiology analyzed the organism of these animals very closely. One of the discoveries they made were significantly elevated quantities of the stress hormone cortisone and of the hormone aldosterone. The latter causes an increase in the concentration of salt in the blood, thereby raising blood pressure. Consequently, the mice drink more water so they can expel the excess salt more successfully.

The studies revealed other striking irregularities. The synapses in the brain release a greater number of transmitters. There is also an overabundance of the hormones CRH and ACTH, which are formed in the brain and the pituitary gland: these two transmitters in a signal chain control the production of the hormones cortisone and aldosterone in the adrenal cortex.

SPRED2, an inhibitor protein

The researchers concluded that if the organism is missing the protein SPRED2 the hormonal signal chain from the brain to the pituitary gland to the adrenal cortex is activated far too strongly. It would appear that the protein has the effect of slowing down this system that the organism sets in motion whenever it has to overcome physical or mental stress.

This therefore means that, hormonally speaking, SPRED2-free mice are in a state of permanent stress. The researchers are therefore interpreting the continuous scratching that they observe with these animals as a stress-related compulsion. “The elevated quantity of cortisone simulates stress for them,” says Kai Schuh. No evidence has been found of other conceivable causes for the scratching, such as diabetes.

Illnesses due to defective SPRED2?

The absence of SPRED2 leads to a hormone surplus with too much cortisone and aldosterone – this would suggest that a malfunction of this gene could have something to do with high blood pressure or other illnesses, such as depression. Scientists are also considering genetic causes for both ailments.

“We are not currently aware of any illnesses in humans that are connected to SPRED2,” says Professor Schuh. But this could all change, as the example of the closely related SPRED1 gene shows: geneticists only recently proved for the first time that a defect to this gene is the sole cause of neurofibromatosis, tumor-like growths of the nerve tissue.

Next steps for the researchers

There are many questions relating to the function of the SPRED2 protein that the Würzburg researchers have yet to answer. They want to work with neurophysiologists to analyze why the synapses in the brain are overactive without the protein. They are also looking in nerve cells for molecules that interact with SPRED2.

Are the mice really scratching because the hormones are simulating a stress situation for them? Behavioral experiments, conducted in collaboration with Professor Klaus-Peter Lesch from the Department of Psychiatry, should answer this question. The scientists are also planning to administer a common antidepressant to the “stressed” animals as an experiment to see whether it might alleviate the symptoms at all.

Identification of Sprouty-related protein with EVH-1 domain (SPRED) 2 as a negative regulator of the Hypothalamic-Pituitary-Adrenal (HPA) axis, Melanie Ullrich, Karin Bundschu, Peter M. Benz, Marco Abesser, Ruth Freudinger, Tobias Fischer, Julia Ullrich, Thomas Renne, Ulrich Walter, and Kai Schuh, The Journal of Biological Chemistry, Vol. 286, Issue 11, 9477-9488, March 18, 2011, DOI 10.1074/jbc.M110.171306

Contact

Prof. Dr. Kai Schuh, Institute of Physiology at the University of Würzburg, T +49 (0)931 31-82740, kai.schuh@uni-wuerzburg.de

Robert Emmerich | idw
Further information:
http://www.uni-wuerzburg.de

Further reports about: Biological Chemistry SPRED2 adrenal cortex blood pressure nerve cell

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>