U.S. Department of Health and Human Services
NATIONAL INSTITUTES OF HEALTH NIH News
National Heart, Lung, and Blood Institute (NHLBI) <http://www.nhlbi.nih.gov/>
Embargoed for Release: Thursday, August 25, 2011, 12 p.m. EDT
CONTACT: NHLBI Office of Communications, 301-496-4236, <e-mail:NHLBI_news@xxxxxxxxxxxxx>
PROTEIN LINKED TO PARKINSON'S DISEASE MAY REGULATE FAT METABOLISM
Preliminary NIH study may have implications for early onset of the disease
National Institutes of Health researchers have found that Parkin, an important protein linked with some cases of
early-onset Parkinson's disease, regulates how cells in our bodies take up and process dietary fats.
Parkinson's disease is a complex, progressive, and currently incurable neurological disorder characterized by
shaking, stiffness, slowed movement, and impaired balance. Parkinson's primarily affects people over 50, but in
about 5 to10 percent of cases it occurs in people as young as their 20s. This form of the disease, which affects
actor, author, and Parkinson's activist Michael J. Fox, is known as early-onset Parkinson's.
Parkin mutations are present in as many as 37 percent of early-onset Parkinson's cases. However, laboratory mice
with defective Parkin do not display obvious signs of the disease.
This preliminary study, which will appear online in the Journal of Clinical Investigation on Aug. 25, suggests
defective Parkin may indirectly contribute to the development of some early-onset Parkinson's by changing the
amount and types of fat in people's bodies.
"This discovery shows that the clues to understand Parkinson's disease may not necessarily be in the brain," said
study leader Michael Sack, M.D., chief of the Laboratory of Mitochondrial Biology in Cardiometabolic Syndromes at
the NIH's National Heart, Lung, and Blood Institute.
The research team, composed of scientists from the NHLBI and the NIH's National Institute of Neurological
Disorders and Stroke, observed that mice with defective Parkin did not gain weight in response to a high-fat
laboratory diet, as regular mice typically do.
When the researchers examined several organs of the Parkin-defective mice, they noticed that the cells contained
low levels of certain proteins that transport fat in the body. In contrast, normal mice that were fed the same
high-fat diet had high levels of these fat-carrying proteins, as well as high levels of Parkin, suggesting that
Parkin is involved in fat transportation.
The researchers saw a similar pattern when they analyzed blood cells from patients enrolled at the NIH
Parkinson's Clinic. In lab tests, cells from people with Parkin mutations had less ability to absorb fat. These
results provide evidence that the findings could be relevant in humans.
As to how fat may be important in Parkinson's, Dr. Sack notes that the brain cells destroyed during the course of
the disease are found in a region called the substantia nigra, which controls movement, among other roles. "The
neurons in this part of the brain are extremely active. Each one has over 300,000 connections and is continuously
transmitting information," he said. "These neurons require good support in the form of their fat and cholesterol
membrane. If the right types of fat aren't available, then cell integrity will be sub-par and they could be prone
to damage."
Dr. Sack and his colleagues plan some early-stage clinical studies on the connection between fat metabolism and
Parkinson's. They will continue working with the NIH Parkinson's Clinic and encourage patients to participate in
the research as it moves forward.
To schedule an interview with Dr. Sack or learn more about the study, contact the NHLBI Office of Communications
at 301-496-4236 or <email:NHLBI_news@xxxxxxxxxxxxx>.
The National Heart, Lung, and Blood Institute (NHLBI) is a component of the National Institutes of Health. NHLBI
plans, conducts, and supports research related to the causes, prevention, diagnosis, and treatment of heart,
blood vessel, lung, and blood diseases; and sleep disorders. The Institute also administers national health
education campaigns on women and heart disease, healthy weight for children, and other topics. NHLBI press
releases and other materials are available online at: <www.nhlbi.nih.gov>.
NINDS <www.ninds.nih.gov> is the nation's leading funder of research on the brain and nervous system. The NINDS
mission is to reduce the burden of neurological disease -- a burden borne by every age group, by every segment of
society, by people all over the world.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes
and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal
agency conducting and supporting basic, clinical, and translational medical research, and is investigating the
causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs,
visit <www.nih.gov>.
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RESOURCES:
-- Parkinson's Disease: Hope Through Research
-- Parkinson's Disease: Challenges, Progress and Promise
-- NHLBI Intramural Research Program
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