Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mysterious cells may play role in ALS

18.11.2010
By tracking the fate of a group of immature cells that persist in the adult brain and spinal cord, Johns Hopkins researchers discovered in mice that these cells undergo dramatic changes in ALS, also known as Lou Gehrig's disease.

A study reported November 17 online in Neuron shows that these cells, called NG2+, grow and expand rapidly during early life, eventually morphing into mature nervous system cells called oligodendrocytes.

These "oligos" help speed the transmission of electrical impulses by providing insulation around nerve cells. This insulation, known as myelin, is disrupted in nervous system diseases such as multiple sclerosis.

The team tracked the fate of NG2+ cells in both normal mice and mice with a mutant form of the SOD1 gene that causes ALS. Using a stringent system that let them color-tag only NG2+ cells and then accurately locate these cells at various times in their development, the researchers found that NG2+ cells normally keep up a quiet program of dividing in adult tissues, sometimes replacing themselves and other times forming new oligos.

A slow and steady turnover of oligodendrocytes may be required throughout life to maintain myelin, says Dwight Bergles, Ph.D., associate professor in The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine. However, the normal developmental program of NG2+ cells goes awry in the spinal cords of ALS mice.

"In the model ALS mice we studied, it's as though NG2+ cells step onto a high-speed treadmill," Bergles says. "They undergo explosive division, morph more readily into abnormal-looking oligodendrocytes and then, uncharacteristically, those differentiated cells quickly die. The brakes that normally hold these cells in check appear to be gone in ALS."

Of special note are provocative data showing this cell type as the most proliferating cell population in the spinal cords of ALS mice, churning out even more oligodendrocytes than in normal mice, says Shin Kang, Ph.D, a research associate in The Solomon H. Snyder Department of Neuroscience.

"This suggests there is significant oligodendrocyte death even before anything else degenerates," he explains, "which identifies a new and important player in the progression of this disease."

All this frenetic oligodendrocyte-generating activity takes place in the central nervous system's gray matter where other cells — the motor neurons — are dying. A body of research shows that after acute trauma to the central nervous system, a short-term upswing in NG2+ activity takes place that may help reduce the extent of damage. Whether this change in behavior of NG2+ cells is protective, or accelerates the death of motor neurons in ALS, is not yet known.

Earlier studies in lab-dish cultures showed that NG2+ cells acted like stem cells, capable of turning into the major cell types in the nervous system, suggesting that they could be harnessed to replace cells that died as a result of injury or disease. However, the Hopkins team saw no evidence that the cells become anything other than oligodendrocytes in both healthy animals and those carrying the ALS mutant gene.

"Although we found that the potential of these cells is more limited than previously thought, it might be possible to coax them to adopt different fates," Bergles says. "We only need to know what factors are restricting their development in the intact nervous system."

"This goes much further than simply confirming a negative finding about these mysterious cells," adds Kang. "We've answered a question, but the new observation about the overgrowth could lead to an entirely new understanding of ALS."

The study was supported by the Packard Center for ALS Research at Johns Hopkins and its sister organization, P2ALS, and by grants from the National Institutes of Health and Muscular Dystrophy Association.

Johns Hopkins authors of the study, in addition to Bergles, are Shin H. Kang, Jason K. Yang, and Jeffrey D. Rothstein. Masahiro Fukaya, Hokkaido University Graduate School of Medicine, Sapporo, Japan, is also an author.

On the Web:

Dwight Bergles: http://www.bergleslab.com/

Neuron: http://www.cell.com/neuron/

Maryalice Yakutchik | EurekAlert!
Further information:
http://www.jhmi.edu
http://www.cell.com/neuron/
http://www.bergleslab.com/

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>