Research Highlights

Researchers Link Two Molecules to Multiple-Sclerosis Nerve Damage

May 1, 2004

Scientists with VA, Yale and University College London identified two molecules that may underlie nerve-fiber degeneration in secondary progressive multiple sclerosis. MS is a disease of the central nervous system that attacks myelin, the protective coating around nerve fibers. In the progressive forms, entire lengths of the nerve fibers begin to degenerate, resulting in permanent and irreparable damage and a steady worsening of symptoms. The new finding is the first observation in humans of specific molecules that contribute to the degeneration of nerve fibers. The researchers examined postmortem spinal-cord tissue from patients with secondary progressive MS and noted a link between nerve damage and the presence of two molecules, Nav. 1.6 and NCX. Located on the surface of most nerve fibers, Nav.1.6 controls the flow of sodium into the cell. This in turn activates NCX, a "sodium-calcium exchanger" that potentially allows excess calcium into the nerve fibers, ultimately causing them to die. The discovery may lead to new therapies to help protect nerve fibers.

Craner MJ, Newcombe J, Black JA, Hartle C, Cuzner ML, Waxman SG. Molecular changes in neurons in multiple sclerosis: altered axonal expression of Nav1.2 and Nav1.6 sodium channels and Na+/Ca2+ exchanger. Proc Natl Acad Sci U S A. 2004 May 25;101(21):8168-73. Epub 2004 May 17