University to Receive More than $6.5 Million to Study Environmental
Risk Factors for Parkinson's Disease
will receive one of three 5-year grants totaling $20 million from the
National Institute of Environmental Health Sciences (NIEHS), a division
of the National Institutes of Health, to study the relationship between
exposures to environmental agents and Parkinson's disease (PD). Parkinson's
disease is a progressive disorder of the central nervous system affecting
over one million people in the United States.
Emory University, the University
of California at Los Angeles and The Parkinson's Institute, Sunnyvale,
CA, will each receive more than $6.5 million to create new centers and
fund research relating to environmental agents that may trigger the
onset of PD. The NIEHS will make the grant announcement on Monday, August
26, in Sunnyvale.
"It's been thought for a
long time that environmental factors, including pesticides, may be important
in causing Parkinson's disease. We are very excited about this new opportunity
to broaden our research efforts in Parkinson's disease and its environmental
causes," says J. Timothy Greenamyre, M.D., Ph.D., professor of neurology
and pharmacology, Emory University School of Medicine, and co-director
of the Emory Neurodegenerative Disease Center. "We already have a strong
program in neurodegenerative diseases, particularly in Parkinson's disease,
and we have a longstanding interest in the links between a person's
genetic make-up, their exposures to environmental toxins, such as pesticides,
and their likelihood of developing PD. I think these new NIEHS Collaborative
Centers will really accelerate the pace of this research."
Dr. Greenamyre will direct
the new center at Emory, which will be called "The Emory Collaborative
Center for Parkinson's Disease Environmental Research." The center will
combine resources from different departments and schools, including
the Emory Neurodegenerative Disease Center, Emory's Department of Neurology
and the Rollins School of Public Health. Clinical and basic research
projects, all targeting gene-environment interactions in Parkinson's
disease, will be led by Dr. Greenamyre, Allan Levey, M.D., Ph.D., professor
of neurology, Emory University School of Medicine and director of the
Emory Neurodegenerative Disease and Gary Miller, Ph.D., associate professor
in the Department of Environmental and Occupational Health, Rollins
School of Public Health at Emory.
- Dr. Greenamyre's research
will focus on pesticides and their role in causing Parkinson's disease.
Rotenone, a commonly used organic pesticide, has attracted a lot of
attention in Dr. Greenamyre's lab. In past studies, Dr. Greenamyre
and colleagues found that rotenone can induce major features of PD
in rats, including slowness, stiffness and tremor. Published in Nature
Neuroscience in November 2000, these results support the idea
that chronic exposure to environmental pesticides may contribute to
the incidence of Parkinson's disease in humans.
With the new funding,
Dr. Greenamyre will continue to research rodent and cell models
of PD to determine which genes cause susceptibility or resistance
to the PD-inducing effects of pesticides.
- Dr. Miller, a neurotoxicologist,
will study the brain's reaction to organochlorine insecticides in
rodents and how these insecticides alter the function of cells that
die in Parkinson's disease. Specifically, he will research how these
chemicals affect storage and release of dopamine, a neurotransmitter
produced by neurons in the brain that is found in steadily decreasing
amounts as the disease progresses. Most organochlorine insecticides
were banned in the 1970's, but because the compounds are very environmentally
persistent, residue can still be found in the soil, the food chain
and in humans.
Using genetically altered
mice models, Dr. Miller will investigate the mechanisms of cell
death following exposure to insecticides.
- Dr. Levey will research
the genetic causes of PD by collecting DNA samples from Emory Parkinson's
patients and performing genetic analyses of those samples. Through
this analysis and a detailed, clinical registry of PD patients, environmental
factors and genetic susceptibility will be examined closely.
Dr. Levey will use brain
samples from post-mortem Parkinson's patients and pesticide-induced
rodent models, which Drs. Greenamyre and Miller will generate, to study
candidate genes, or genes of interest, in connection to environmental
exposure and PD.
Because the new Emory Collaborative
Center for Parkinson's Disease Environmental Research is a joint endeavor,
adding Dr. Miller's expertise in the fields of toxicology and public
health will expand research to include new approaches to PD prevention.
"If we can figure out how insecticides contribute to PD, it will help
us develop strategies to prevent or treat the disease in the future,"
Dr. Miller explains. "The solution is not to ban pesticides and insecticides,
because these products are very important in crop production and insect
control. However, it may be necessary to reevaluate the regulatory guidelines
for pesticides, taking into consideration the risks for Parkinson's
disease while not dismissing the positive impact these chemicals have
on public health."
Dr. Miller is a new recruit
in the Emory Neurodegenerative Disease Center, a center established
just four months ago through a $3 million gift. The center brings together
scientists from different disciplines to enhance research opportunities
and strengthen clinical services for patients with neurodegenerative
diseases. "This NIEHS grant is made possible through the collaborative
efforts of the Emory Neurodegenerative Disease Center and through new
faculty members like Dr. Miller," Dr. Levey points out. "It exemplifies
the power of people working together from different aspects and approaches."