Featured Research

from universities, journals, and other organizations

PCBs, Fungicide Open Brain Cells To Parkinson's Assault

Date:
January 31, 2005
Source:
University Of Rochester Medical Center
Summary:
University of Rochester scientists investigating the link between PCBs, pesticides and Parkinson’s disease demonstrated new and intricate reactions that occur in certain brain cells, making them more vulnerable to injury after exposures.

University of Rochester scientists investigating the link between PCBs, pesticides and Parkinson’s disease demonstrated new and intricate reactions that occur in certain brain cells, making them more vulnerable to injury after exposures.

In two papers published in the journal NeuroToxicology (Dec. 2004 and Feb. 2005), the group describes how Polychlorinated biphenyls (PCBs) disrupt dopamine neurons, which are the cells that degenerate during the course of Parkinson’s disease. Researchers also show that low levels of maneb, a fungicide commonly used in farming, can injure the antioxidant system in those same types of cells. Environmental contaminants might make dopamine cells more vulnerable to damage from normal aging, infection, or subsequent exposure to pollutants, researchers say.

The UR investigation is part of a nationwide race to better understand every aspect of Parkinson’s disease, which affects up to 1 million Americans. It is a progressive neurological disorder that occurs when certain nerve cells in the substantia nigra region of the brain die or can no longer produce the brain chemical dopamine. A lack of dopamine is what causes patients to experience tremors, stiffness in the limbs and trunk, and impaired movement or balance.

In the 1990s scientists reported that the brains of Parkinson’s patients contained elevated levels of PCBs and certain pesticides. While researchers believe that genetics, the aging process and exposure to toxicants all play a role in the development of Parkinson’s, the UR group led by Lisa Opanashuk, Ph.D., is focused on environmental exposures. The National Institutes of Health is funding the work.

“If we can identify the mechanisms by which PCBs or pesticides perturb dopamine neuron function, it may lead to the development of therapies that can prevent, slow or stop the progression of Parkinson’s,” says Opanashuk, an assistant professor of Environmental Medicine.

PCBs create havoc in the body’s cellular system by producing free radicals, which leads to a process known as oxidative stress (OS). Oxidative stress is thought to be one of the main causes of cell degeneration. Normally, antioxidants can balance the damage done by OS. But toxic pesticide exposure, combined with the normal aging process, shifts the equilibrium toward oxidative stress and neurodegeneration.

The UR studies demonstrate, for the first time, the intricate OS and antioxidant responses to PCBs in dopamine neurons. Investigators treated dopamine cells and other brain cells with PCBs and documented the activation of oxidative-stress related pathways. Further research will evaluate how PCBs become risk factors for disease.

PCBs, used as industrial coolants and lubricants, were banned in 1977 but remain widespread in the environment due to their improper disposal. They linger in the food chain, particularly in wild and farmed salmon and other fish. PCBs accumulate in the body in fat and brain cells and other tissues. The potential adverse health effects of PCBs are dependent upon many factors, such as the levels of exposure, the toxicities of individual chemicals present in any given mixture, and their interactive properties.

Pesticides such as maneb remain in farmed soil for 20-75 days following application and can be found on produce for more than three weeks, even after washing, according to researchers. Until now, the effect of maneb on oxidative stress responses in dopamine neurons was unknown.

But Opanashuk’s group shows that just as in exposure to PCBs, cells treated with low levels of maneb also undergo changes that disturb the balance in the antioxidant defense system. Another concern is whether maneb causes more damage when people are exposed in combination with other pesticides, which occurs in rural communities. Opanashuk hopes the research will lead to developing safety guidelines and determining more closely the role that maneb plays in neurological diseases.

Besides Opanashuk, the research group included Donna W. Lee and Mary Williamson, fifth year graduate students in the Toxicology PhD. Program, technician Bryan Thompson, and former UR scientists Brian K. Barlow and Deborah Cory-Slechta, who are now associated with the Robert Wood Johnson Medical School in New Jersey. The UR is also home to the Parkinson’s Disease Data and Organizing Center, directed by Roger Kurlan, M.D., a nationwide network of 12 institutions, and the Parkinson Study Group, a consortium of experts founded and headed by UR neurologist Ira Shoulson, M.D.


Story Source:

The above story is based on materials provided by University Of Rochester Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

University Of Rochester Medical Center. "PCBs, Fungicide Open Brain Cells To Parkinson's Assault." ScienceDaily. ScienceDaily, 31 January 2005. <www.sciencedaily.com/releases/2005/01/050128224727.htm>.
University Of Rochester Medical Center. (2005, January 31). PCBs, Fungicide Open Brain Cells To Parkinson's Assault. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2005/01/050128224727.htm
University Of Rochester Medical Center. "PCBs, Fungicide Open Brain Cells To Parkinson's Assault." ScienceDaily. www.sciencedaily.com/releases/2005/01/050128224727.htm (accessed September 2, 2014).

Share This




More Mind & Brain News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
Coffee Then Napping: The (New) Key To Alertness

Coffee Then Napping: The (New) Key To Alertness

Newsy (Aug. 30, 2014) Researchers say having a cup of coffee then taking a nap is more effective than a nap or coffee alone. Video provided by Newsy
Powered by NewsLook.com
Young Entrepreneurs Get $100,000, If They Quit School

Young Entrepreneurs Get $100,000, If They Quit School

AFP (Aug. 29, 2014) Twenty college-age students are getting 100,000 dollars from a Silicon Valley leader and a chance to live in San Francisco in order to work on the start-up project of their dreams, but they have to quit school first. Duration: 02:20 Video provided by AFP
Powered by NewsLook.com
Baby Babbling Might Lead To Faster Language Development

Baby Babbling Might Lead To Faster Language Development

Newsy (Aug. 29, 2014) A new study suggests babies develop language skills more quickly if their parents imitate the babies' sounds and expressions and talk to them often. Video provided by Newsy
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