Myelin is the material sheathing axons in nerve cells. A number of conditions involve loss of myelin, such as multiple sclerosis (MS), but loss of myelin integrity occurs to a lesser degree for all of us as we age, and is thought to contribute to the characteristic cognitive decline of later years. Thus research into ways to regenerate myelin sheathing has broad potential application and is worth keeping an eye on:
We have identified a whole new target for drugs that might promote repair of the damaged brain in any disorder in which demyelination occurs. Any kind of therapy that can promote remyelination could be an absolute life-changer for the millions of people suffering from MS and other related disorders.
In 2005, [researchers] discovered that a sugar molecule, called hyaluronic acid, accumulates in areas of damage in the brains of humans and animals with demyelinating brain and spinal cord lesions. Their findings at the time [suggested] that hyaluronic acid itself prevented remyelination by preventing cells that form myelin from differentiating in areas of brain damage. The new study shows that the hyaluronic acid itself does not prevent the differentiation of myelin-forming cells. Rather, breakdown products generated by a specific enzyme that chews up hyaluronic acid - called a hyaluronidase - contribute to the remyelination failure.
This enzyme is highly elevated in MS patient brain lesions and in the nervous systems of animals with an MS-like disease. The research team [found] that by blocking hyaluronidase activity, they could promote myelin-forming cell differentiation and remyelination in the mice with the MS-like disease. Most significantly, the drug that blocked hyaluronidase activity led to improved nerve cell function. The next step is to develop drugs that specifically target this enzyme.