OFF TOPIC: News Item: Pregnancy hormone key to repairing nerve cell damage

[Guest guest]

Another interesting research item:

Pregnancy hormone key to repairing nerve cell damage

February 20, 2007

New research offers hope for treatment of multiple sclerosis and other

neurological disorders

The mystery of why multiple sclerosis (MS) tends to go into remission while

women are pregnant may be the

secret to overcoming the devastating neurodegenerative disease, according to

University of Calgary researchers

who have shown that a pregnancy-related hormone is responsible for rebuilding

the protective coating around

nerve cells.

In a paper to be published in the February 21 issue of The Journal of

Neuroscience, a team of researchers from

the U of C's Faculty of Medicine reports that a study conducted on mice found

that the hormone prolactin

encourages the spontaneous production of myelin, the fatty substance that coats

nerve cells and plays a

critical role in transmitting messages in the central nervous system. A

collaboration between the laboratories

of Drs. Weiss and V. Wee Yong of the Hotchkiss Brain Institute, the study

is the first to determine

that prolactin, which increases in the body during pregnancy, is directly

responsible for the formation of new

myelin in the brains and spinal cords of pregnant mice. Further, when

non-pregnant mice with MS-like lesions

were injected with prolactin, their myelin was also repaired.

The research was based on evidence that MS, which is more common in women than

men, goes into remission when

women become pregnant. MS is a neurodegenerative disease where the body's own

immune system attacks the myelin

surrounding nerves, leading to progressive loss of sensation and movement. MS

affects approximately 2.5

million people worldwide and Canadians have one of the highest rates of the

disease in the world.

" It is thought that during pregnancy, women's immune systems no longer destroyed

the myelin, " said Weiss,

director of the Hotchkiss Brain Institute and senior author of the study.

" However, no previous study has

tested whether pregnancy actually results in the production of new myelin, which

may lead to improvement of

symptoms. " The paper's findings represent the first example of a natural,

biological mechanism that produces

new myelin in the adult brain and spinal cord and identifies prolactin as a

potential therapeutic substance

for future testing in people with MS.

" Agents promoting remyelination will be beneficial not only for typical

demyelinating diseases like MS, " says

Dr. Fred (Rusty) Gage, of the Salk Institute, " but also for many other

neurological disorders, such as spinal

cord injuries and stroke. " Gage, an international leader in nervous system

repair, was not involved in this

study.

Subsequent tests of prolactin in animal models of MS will be required before

testing of prolactin on humans

can take place, but MS researchers are hopeful human trials can take place

within the next several years.

" This discovery has the potential to take MS therapy a step further than current

treatments that stabilize the

disease in its early stages. By promoting repair, which is the goal of prolactin

therapy, we have hope of

actually improving symptoms in people with MS, " says Dr. Luanne Metz, director

of the Calgary MS Clinic in the

Department of Clinical Neurosciences, University of Calgary and Calgary Health

Region.

The study, authored by Weiss, Gregg, Viktor Shikar, Larsen,

Gloria Mak, Chojnacki and

Yong, compared pregnant and virgin female mice of the same age and found that

pregnant mice had twice as many

myelin-producing cells, called oligodendrocytes, and continued to generate new

ones during pregnancy. By

chemically destroying myelin around nerve cells, the researchers found that

pregnant mice had twice as much

new myelin two weeks following the damage as virgin mice and that introducing

prolactin mimicked the effects

of pregnancy on myelin production and repair in mice that weren't pregnant.

" The results of this study should be well received by people living with MS

today, " said Dr. McIlroy,

national medical advisor for the Multiple Sclerosis Society of Canada. " It

represents a new insight of how we

might be able to reverse some of the effects of the disease and improve the

quality of life for those who live

under its influence. "

The study was funded by the Canadian Institutes of Health Research and the

Multiple Sclerosis Society of

Canada, with the support of the Alberta Heritage Foundation for Medical Research

and the Stem Cell Network.

The journal article " White matter plasticity and enhanced remyelination in the

maternal CNS " will be published

in the Feb. 21 issue of The Journal of Neuroscience. The journal is published by

the Society for Neuroscience,

an organization of more than 36,500 basic scientists and clinicians who study

the brain and nervous system.

Media reporting on the paper is subject to The Journal of Neuroscience embargo

rules, which state that the

study is embargoed until February 20, 2007 at 5:00 pm Eastern Time.

About the Hotchkiss Brain Institute

The Hotchkiss Brain Institute, established by the University of Calgary and the

Calgary Health Region, is

dedicated to neurological and mental health research and education, leading to

new discoveries and their

translation into improved patient care. It is the first research institute of

its kind in Western Canada.

About the Faculty of Medicine, University of Calgary

The UofC's Faculty of Medicine is a national leader in health research with an

international reputation for

excellence and innovation in health care research, education and delivery.

Through its educational programs,

the Faculty of Medicine trains the physicians and scientists who will lead the

next generation of health

practitioners. Through its clinical work, continuing medical education programs,

and close relationship with

the Calgary Health Region, the Faculty of Medicine moves new treatments and

diagnostic techniques from the

laboratory bench to the hospital bedside efficiently and effectively, improving

patient care.

About multiple sclerosis and the Multiple Sclerosis Society of Canada

Multiple sclerosis is a chronic, often disabling disease of the brain and spinal

cord. It is the most common

neurological disease of young adults in Canada. Most people with MS are

diagnosed between the ages of 15-40,

and the unpredictable effects of MS last for the rest of their lives. The MS

Society provides services to

people with MS and their families and funds research to find the cause and cure.

Visit www.mssociety.ca for

more information.

http://www.ucalgary.ca/news/feb2007/ms-hormone/