might help treat multiple sclerosis (MS), Canadian researchers report.
So far, the scientists -- who work at the University of Calgary -- have only
studied prolactin in female mice, not in people.
But they note that MS symptoms often ease in human pregnancy, possibly
because of prolactin.
If so, prolactin could hold promise as a treatment for MS, note the
researchers, who included Samuel Weiss, PhD.
In multiple sclerosis, the body's immune system attacks the fatty sheath,
called myelin, that protects nerves in the brain and spinal cord.
"It was thought that during pregnancy, [women's] immune systems no
longer destroyed the myelin," Weiss says in a Society for Neuroscience news
"But no previous study has tested whether pregnancy actually results in
the production of new myelin, which may explain improvement of symptoms,"
Weiss and colleagues studied pregnant and virgin female mice with damage to
They found that pregnant mice had both more prolactin and myelin-producing
cells than the virgin mice.
The pregnant mice also did better at repairing their myelin damage than the
virgin mice, the study shows.
Next, the scientists injected prolactin into virgin mice. Afterwards, the
virgin mice boosted their number of myelin-producing cells and improved their
ability to repair myelin damage.
If the findings are confirmed in further studies, prolactin may prove useful
in treating MS, note Weiss and colleagues.
However, they suggest that since prolactin can increase inflammation, it
might need to be combined with anti-inflammatory medicine.
The study appears in The Journal of Neuroscience.
By Miranda Hitti
Reviewed by Louise Chang
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