Alzheimer's, Dementia & Mental Health
Death of Neurons
Causing Parkinson’s Disease is Due to Exhaustion from Stress
Parkinson's disease
is second to Alzheimer’s as most common
neurodegenerative disease in U.S.; the average age of diagnosis is about
60
Nov. 10, 2010
-
All senior citizens know that living a stressful lifestyle can take its
toll, making us age faster and making us more susceptible to the latest
cold going around. The same appears to be true of dopamine-releasing
neurons in the brain. New research finds when these neurons become
stressed out they die, which causes Parkinson’s disease.
According to a
new Northwestern Medicine study published Nov. 10 in the journal
Nature, dopamine-releasing neurons in a region of the brain called
the "substantia nigra" lead a lifestyle that requires lots of energy,
creating stress that could lead to the neurons' premature death. Their
death causes Parkinson's disease.
"Why this small
group of neurons dies in Parkinson's disease is the core question we
struggled with," says lead author D. James Surmeier, the Nathan Smith
Davis Professor and chair of physiology at Northwestern University
Feinberg School of Medicine.
"Our research
provides a potential answer by showing this small group of neurons uses
a metabolically expensive strategy to do its job. This 'lifestyle'
choice stresses the neurons' mitochondria and elevates the production of
superoxide and free radicals – molecules closely linked to aging,
cellular dysfunction and death."
The good news is
preclinical research shows this stress can be controlled with a drug
already approved for human use. By preventing calcium entry, the drug
isradipine reduced the mitochondrial stress in dopamine-releasing
neurons to the levels seen in neurons not affected by the disease.
Northwestern
Medicine scientists currently are conducting a clinical trial to find
out if isradipine can be used safely and is tolerated by patients with
Parkinson's. Isradipine is already approved by the Food and Drug
Administration for treatment of high blood pressure.
Parkinson's
disease is the second most common neurodegenerative disease in the
United States, second only to Alzheimer's disease. The average age of
diagnosis is near 60. More than 1 million Americans currently have
Parkinson's disease, and this number is rising as the population ages.
The symptoms of
Parkinson's disease include rigidity, slowness of movement and tremors.
No treatment currently is known to prevent or slow the progression of
Parkinson's disease.
Although most
cases of Parkinson's disease have no known genetic link, Surmeier's
study in mice showed that the mitochondrial stress in dopamine-releasing
neurons was worsened in a genetic model of early-onset Parkinson's
disease, suggesting a similar mechanism in rare familial forms of the
disease and the more common forms.
Everyone loses
dopamine-releasing neurons with age, Surmeier noted. "By lowering their
metabolic stress level, we should be able to make dopamine-releasing
neurons live longer and delay the onset of Parkinson's disease," he
said.
"For individuals
diagnosed with Parkinson's disease, the hope is that this drug can slow
disease progression, giving symptomatic therapies a broader window in
which to work."
The study was
supported by the National Institutes of Health, United States Department
of Defense, Thomas Hartman Foundation For Parkinson's Research, Inc.,
The Picower Foundation and Dr. Ralph and Marian Falk Medical Research
Trust.
Links to Archived News Reports About
Parkinson's Disease
Seniors, Other Parkinson Patients Gain from Deep
Brain Stimulation but Take Serious Risk
Few previous randomized trials comparing treatments,
most excluded senior citizens - watch video - Jan. 7, 2009
Physical Activity Slows the Progress of Parkinson’s
in Study
U. of Michigan programs promote strengthening and
conditioning of patients
Aug. 11, 2008
Parkinson's Community Steps Out to Find a Cure at
the 14th Annual Parkinson's Unity Walk
Second most common chronic neurological disorder in
senior citizens after Alzheimer's
April 23, 2008
Parkinson’s Patients Play Nintendo to Test Occupational Therapy
Foul ball and improved walking ability brings a cheer
for Ingrid Bell
April 7, 2008
Researchers Claim Omega-3 Fatty Acids Protect Brain
from Parkinson's
Protection may come from DHA omega-3 eating up
dangerous omega-6 fatty acid in brain
Nov. 26, 2007
PET Scans Show
Gene Therapy Normalizes Brain Function in Parkinson’s
Study focuses on power of modern brain scans
to show that gene therapy altered brain activity in a favorable
way
Nov. 20, 2007
It's How Amyloid Fiber is Built that May Set Stage
for Alzheimer's, Parkinson's
Study of bacteria’s role in forming fibers leads to
new theory
July 13, 2007
Exelon Patch is First Approved by FDA to Treat
Alzheimer’s Disease
Patch also approved to treat Parkinson's disease
dementia
July 9, 2007
New Treatment in Battle Against Parkinson’s May Come
from Discovery
New protein appears to protect and rescue damaged
dopamine neurons
July 5, 2007
Parkinson’s Disease Risks Lower with High Levels of
Urate in Blood
Large Harvard study finds potent antioxidant works
against oxidative stress
June 22, 2007
Parkinson’s Disease Treatment with Gene Therapy
Shows Promise
First such clinical trial may lead to effective
management of disease that hits mostly senior citizens
June 22, 2007
Engineers Say They Now Know How Brain Pacemakers
Help Parkinson’s Patients
Deep brain stimulation erases diseased messages for
thousands
May 31, 2007
Alzheimer's, Parkinson's, Diabetes, Mad Cow
Similar
at Molecular Level
Protein analysis may offer new diagnoses and
treatment options
April 30, 2007
Parkinson's Treatment Drugs Being Withdrawn, Says
FDA
Permax (pergolide) and two generic versions may
damage heart valves
March 29, 2007
Major Parkinson's Trial Begins Testing Energy
Booster's Ability to Slow the Disease
Creatine to be tested in 52 sites with 1,720
participants
March 22, 2007
Australians Claim Low-Cost Gene Screening for
Parkinson's Disease
Seeks people for gene-sequencing trial,
Australia-wide gene-mapping study
Feb. 23, 2007
Parkinson's Linked to Low LDL Cholesterol
that is Good for Heart
People with Parkinson's have lower rate of heart
attack and stroke
December 20, 2006
Cell Activities that
Protect against Alzheimer's Protein Buildup Found
Findings may lead to new therapies for
Neurodegenerative Diseases such as Alzheimer's and Parkinson's
August 11, 2006
Researchers find 'Probable Cause' for Parkinson's,
Alzheimer's, other Brain Disorders
June 28, 2006
