Featured Research

from universities, journals, and other organizations

Exposure To Environmental Toxics Accelerates Age-related Parkinson's Disease In Mice

Date:
June 29, 2007
Source:
Buck Institute for Age Research
Summary:
Scientists at the Buck Institute for Age Research have shown that combining two environmental toxic substances accelerated age-related degeneration in neurons associated with Parkinson's disease (PD) in mice. Additionally, the study showed that pre-treating the mice with an antioxidant weakened the impact of the environmental exposures, suggesting the substances damage the neurons via oxidative stress. The toxics involved include increased neonatal iron intake and exposure to the herbicide paraquat.

Scientists at the Buck Institute for Age Research have shown that combining two environmental toxic substances accelerated age-related degeneration in neurons associated with Parkinson’s disease (PD) in mice. Additionally, the study showed that pre-treating the mice with an antioxidant weakened the impact of the environmental exposures, suggesting the substances damage the neurons via oxidative stress. The toxics involved include increased neonatal iron intake and exposure to the herbicide paraquat. Results of the study were published in the June 27 issue of The Journal of Neuroscience.

The study highlights the role of environmental factors in the development of PD, a progressive, incurable neurodegenerative disorder that results in tremor, slowness of movement and rigidity. Only five percent of the 160,000 cases of PD diagnosed in the U.S. each year are strictly genetic in nature; most of those afflicted have “sporadic” PD, likely due to a combination of environmental exposures and increased genetic susceptibilities. “Research keeps pointing to Parkinson’s disease as being a very complex disorder,” said Buck Institute faculty member Julie K. Andersen, lead author of the study. “This research looked at environmental risk factors in the context of aging which is essential, given the fact that aging is the single major risk factor for PD in humans.”

Andersen and her team worked with genetically identical mice, which put all the animals on the same footing in regards to genetic susceptibility. One group was given an excess of iron in infancy, another was given the herbicide paraquat, (both compounds have been shown to increase the risk of PD in earlier studies in mice), a third group was exposed to both substances and a fourth group was not exposed to either of the compounds. Half of each group received treatment with the antioxidant EUK-189, which is known to cross the blood brain barrier. The animals in each group were aged to the human equivalent of young adult, young middle-age (45 – 55 in humans), young-older (65 – 70 and elderly (85+). Results showed that exposing animals to both substances accelerated PD-like neurodegeneration in the mice, with symptoms beginning to appear at the human equivalent of middle-age. The mice demonstrated a progression of increased oxidative stress followed by decreased neuronal function and finally neuronal cell loss. In elderly mice, cell loss was roughly equivalent to that observed in the human disorder. Those mice treated with the antioxidant, which was delivered at the same time as the environmental toxin, had significantly less nerve death in the area of the brain commonly affected by PD.

“The fact that the antioxidant treatment prevented much of the nerve damage in the mice points to the need for an early diagnostic test for Parkinson’s disease,” said Andersen. “Currently, by the time humans are diagnosed with the disease they have already lost 60% of the neurons implicated in PD; treatment with an antioxidant would likely be maximally effective if taken before symptoms appear in order to halt disease progression.”

J. Timothy Greenamyre, MD, PhD, Professor of Neurology at the University of Pittsburgh commented on the work, “This study provides further confirmation that ‘innocuous’ early life events or exposures can lead to late life neurodegeneration. Secondly, it adds to the evidence that that abnormalities of iron handling can contribute to the pathogenesis of PD.” He added, “It also shows that early life exposures can predispose to or exacerbate neurodegeneration caused by subsequent exposures.”

Joining Andersen in the study were Jun Peng, and Fang Feng Stevensen, also of the Buck Institute, along with Li Peng of the Royal Perth Hospital, Perth, Australia; and Susan R. Doctrow of Proteome Systems, Inc., Woburn, MA. The work was funded by the National Institute of Environmental Health Sciences as part of a large Collaborative Centers for Parkinson’s Disease Environmental Research (CCPDER) U54 grant.


Story Source:

The above story is based on materials provided by Buck Institute for Age Research. Note: Materials may be edited for content and length.


Cite This Page:

Buck Institute for Age Research. "Exposure To Environmental Toxics Accelerates Age-related Parkinson's Disease In Mice." ScienceDaily. ScienceDaily, 29 June 2007. <www.sciencedaily.com/releases/2007/06/070627133328.htm>.
Buck Institute for Age Research. (2007, June 29). Exposure To Environmental Toxics Accelerates Age-related Parkinson's Disease In Mice. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2007/06/070627133328.htm
Buck Institute for Age Research. "Exposure To Environmental Toxics Accelerates Age-related Parkinson's Disease In Mice." ScienceDaily. www.sciencedaily.com/releases/2007/06/070627133328.htm (accessed July 23, 2014).

Share This




More Plants & Animals News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Stone Fruit Listeria Scare Causes Sweeping Recall

Stone Fruit Listeria Scare Causes Sweeping Recall

Newsy (July 22, 2014) The Wawona Packing Company has issued a voluntary recall on the stone fruit it distributes due to a possible Listeria outbreak. Video provided by Newsy
Powered by NewsLook.com
Michigan Plant's Goal: Flower and Die

Michigan Plant's Goal: Flower and Die

AP (July 22, 2014) An 80-year-old agave plant, which is blooming for the first and only time at a University of Michigan conservatory, will die when it's done (July 22) Video provided by AP
Powered by NewsLook.com
Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Huge Schizophrenia Study Finds Dozens Of New Genetic Causes

Newsy (July 22, 2014) The 83 new genetic markers could open dozens of new avenues for schizophrenia treatment research. Video provided by Newsy
Powered by NewsLook.com
CDC Head Concerned About a Post-Antibiotic Era

CDC Head Concerned About a Post-Antibiotic Era

AP (July 22, 2014) Sounding alarms about the growing threat of antibiotic resistance, CDC Director Tom Frieden warned Tuesday if the global community does not confront the problem soon, the world will be living in a devastating post-antibiotic era. (July 22) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins