Scientific American makes note of a new finding regarding multiple
sclerosis, first reported in The Journal of Neuroscience.
 

One of the big shifts in our understanding of brain structure and
function, over the past decade or so, has been our improved
understanding of the process of href="http://en.wikipedia.org/wiki/Neurogenesis">neurogenesis
in adults.  It is more more common than had been assumed
previously.  It turns out that neurons are not the only brain
cells that change in such dynamic ways.  New href="http://en.wikipedia.org/wiki/Neuroglia">neuroglia
can be generated as well.

This is potentially important to the pathophysiology of demyelinating
illnesses such as MS.  Since myelin is produced by
oligodendrocytes, it is conceivable that creating more oligodendrocytes
could alleviate the disease.

The investigators in the study were investigating the observation that
MS often improves during pregnancy.  At first, they thought
this probably was due to changes in the immune system.  They
developed mouse models to investigate this.  What they found
was a complete surprise.

href="http://www.sciam.com/article.cfm?chanId=sa003&articleId=F0C97267-E7F2-99DF-3230A25CB13C55A4">Hormonal
Surge During Pregnancy Repairs Faulty Brain Signaling
New study finds that the release of prolactin
strengthens neuron insulation, which could one day help reduce the
effects of multiple sclerosis
By Nikhil Swaminathan

In what could give hope to the 2.5 million sufferers
of multiple sclerosis (MS) worldwide, a new study reports that the
hormone prolactin, the levels of which spike during pregnancy, mended
nerve damage in mice…

…”It was thought that during pregnancy, their immune systems no
longer destroyed the myelin,” says Samuel Weiss of Hotchkiss Brain
Institute in Calgary and co-author of the study published in The
Journal of Neuroscience. “No previous study has tested whether
pregnancy actually results in the production of new myelin, which may
explain [the] improvement of symptoms.”…

Through an elegant series of experiments, they developed strong
evidence to suggest that it is the increase in prolactin during
pregnancy that results in an increase in the number of
oligodendrocytes, and an increase in the amount of myelin produced.
 

Of course, this is still a long way from any potential clinical
application in humans, but still, it is a very encouraging finding.