More MS news articles for April 2001

International Conference Held to Understand and Prevent Nerve Cell Damage in MS
 
http://www.nationalmssociety.org/Research-2001Apr27-2.asp

April 26, 2001

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Summary: Top experts in the research of MS and related diseases met in New Orleans on March 18-21, 2001 to discuss “Neuronal Injury in MS and Related Disorders: Mechanisms and Prevention” – how and why nerve cells are damaged in MS, and how they might be protected. The National MS Society organized and supported this international workshop.

Damage to nerve cells (neurons) is an area of growing concern in MS research: Evidence indicates that this damage occurs early in the course of the disease, and may be a major contributor to progressive disability in later stages.
The Society brought together nearly 100 basic and clinical experts from around the globe to discuss methods of measuring injury to neurons in MS and related disorders, explanations for how and why neurons are damaged or disrupted, and therapeutic possibilities.

A summary of the proceedings is soon to be published in a major journal. A follow-up workshop is planned, which will focus on methods of repairing damaged neurons.
Details: Top experts in the research of MS and related diseases met in New Orleans on March 18-21, 2001 to discuss “Neuronal Injury in MS and Related Disorders: Mechanisms and Prevention” – how and why nerve cells are damaged in MS, and how they might be protected. The National MS Society organized and supported this international workshop, which was chaired by Stephen G. Waxman, MD, PhD (Yale University Medical School, New Haven, CT) and W. Ian McDonald, MB, ChB, PhD (Royal College of Physicians, London).

Damage to nerve cells (neurons) is an area of growing concern in MS research: Evidence indicates that this damage occurs early in the course of the disease, and may be a major contributor to progressive disability in later stages. The Society brought together nearly 100 basic and clinical experts from around the globe to discuss this important topic. Such meetings create a vital forum where researchers are stimulated to share findings – these discussions often spawn new ideas and collaborations that greatly advance both basic and clinical research.

Additional support for the conference was provided by the MS International Federation, Acorda Therapeutics, Bayer AG, Berlex Laboratories, Biogen, Immunex Corporation, Serono Laboratories, Inc. and Teva Marion Partners.

Proceedings: “MS is traditionally thought of as a demyelinating disorder,” noted Dr. Waxman in introducing the workshop, referring to damage to myelin, the substance that insulates nerve fibers. “There is an immense effort to understand myelin and glial cells [the cells that make myelin] as disease targets. Now attention is turning to neurons. Why do neurons die in MS? How can we intercede and protect them? This may present us with another target for developing therapies for MS.”

This is not a new realization, however, noted Dr. McDonald, referring particularly to damage to axons – extensions of neurons that allow them to transmit electrical impulses. “Axonal loss was recognized by Jean-Martin Charcot, when he first described MS in 1868, and several times since,” he said. “Now it is getting the emphasis it deserves. Permanent disability arises because of the loss of axons. Even if people with relapsing-remitting MS experience complete remissions, they still may progress to disability, and this relates to axonal loss.”

The discussions began with presentations from top experts in disorders where neuronal injury also plays a role, such as Guillain-Barre Syndrome (a disease of the peripheral nervous system that involves myelin loss), HIV-associated dementia and stroke. Researchers shared ideas on what causes the loss of neurons in these disorders, and described some therapeutic possibilities that may be applicable to MS.

Next, presenters reviewed methods of measuring injury to neurons and axons in MS. MRI (magnetic resonance imaging) reveals the loss of axons in the form of “black holes” in MS lesions (areas of disease activity). Novel computerized analyses that measure brain volume changes can be applied to MRI images to study the pattern and rate of brain tissue changes and loss. MRS (magnetic resonance spectroscopy, which evaluates levels of certain key chemicals in the brain) can demonstrate reductions in n-acetyl aspartate, a chemical marker that indicates whether nerve cells are intact and functioning properly.

Speakers suggested explanations for how and why neurons are damaged or disrupted in MS. Because this damage often is seen in active, inflammatory lesions, researchers suggested that the immune attack in MS may target neurons directly, and not just myelin. For example, evidence was presented that a naturally occurring molecule, nitric oxide – which can be elevated in inflammation and immune attack – may be a culprit in inducing damage to axons. Other explanations focused on the tight-knit relationship between nerve fibers and the myelin sheath: tiny changes in the formation of myelin can dramatically affect the function of neurons.

Therapeutic possibilities were also discussed. The involvement of the immune system implies that therapies that control inflammation may help protect neurons. It was suggested that blocking sodium channels, tiny pores involved in nerve conduction, might help to protect axons and enhance nerve conduction. Considering the tight-knit relationship between myelin and axons, it was suggested that axonal damage may be prevented by therapies that encourage myelin repair. These include the future possibility of stem cell transplantation – transplanting immature cells into the central nervous system which then grow into myelin-making cells and may repair myelin. Although preliminary, these suggestions present exciting opportunities for further research.

Conclusions: The National MS Society-sponsored conference on “Neuronal Injury in MS and Related Disorders” provided a stimulating forum for basic and clinical scientists to come together and discuss this fast-moving aspect of MS research. A summary of the proceedings is soon to be published in a major journal. A follow-up workshop is planned, which will focus on methods of repairing damaged neurons.

--Research Programs Department