Closing in on treatment for Charcot-Marie-Tooth disease?


Charcot-Marie-Tooth (CMT) is a hereditary disorder of the peripheral nervous system that strikes 1 person in every 2500. Increasing debilitation of the muscles ultimately leads to their disappearance in the lower legs, feet and hands. Now, researchers from VIB (the Flanders Interuniversity Institute for Biotechnology) have discovered a piece of the molecular puzzle of this disease. Two small 'heat shock' proteins turn out to be crucial - faults in the coding genes lead to the disease. Additional research has shown that these proteins play an important role in many other neurodegenerative disorders as well. This research moves us a step closer to the development of new therapies.

CMT, a serious disorder without a cure

CMT, the most common hereditary disorder of the peripheral nervous system, leads to debilitation of the muscles in the lower legs, feet and hands. The clinical picture is extremely variable, but older patients sometimes require a wheelchair. Today, only supportive treatment is available; there are still no effective therapies to retard or stop the progress of the disease. More insight into the molecular processes of this disease is essential for diagnosis and potential treatment. And exploration of the genes involved is a crucial step in this.

VIB research findings

Joy Irobi and her colleagues - under the direction of Vincent Timmerman and Peter De Jonghe of the Department of Molecular Genetics, University of Antwerp - are concentrating on the genetic and biological study of hereditary disorders of the peripheral nervous system. The largest cells in our body, our peripheral neurons can be 1 meter long in bundles of nerve fibers extending from the spinal cord to the feet.

Recently, the researchers in Antwerp have found mutations in the genetic code of two small 'heat shock' proteins (HSPs) in a number of people with CMT. In stress situations, cells produce HSPs that act as 'chaperones', stabilizing other proteins and protecting against degradation. The specific function of the two HSPs in our peripheral nerves has not yet become clear, but the mutations that have been discovered in several European families are now leading to serious symptoms.

Toward new therapies

The scientists have shown that the mutations lead to a stronger interaction between the two HSPs. This causes a precipitation in cultured cells and reduces the viability of neurons. These findings demonstrate the importance of HSPs in neurodegenerative disorders. The team's research results will open the way for new progress in the development of therapies for these hereditary nervous disorders. These HSPs have previously been studied in Amyotrophic Lateral Sclerosis (ALS, or Lou Gehrig's disease), a serious acquired disorder of the nervous system. Hopefully, the discovery of the mutations in the two HSPs will now lead to new insights into this disorder as well.

Source: Eurekalert & others

Last reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
    Published on All rights reserved.