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 Individual Receptors Caught at Work
19.10.2017 | Julius-Maximilians-Universität Würzburg

nachricht Rapid environmental change makes species more vulnerable to extinction
19.10.2017 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>