Featured Research

from universities, journals, and other organizations

In what ways does lead damage the brain? It derails the brain's center for learning

Date:
February 29, 2012
Source:
Columbia University's Mailman School of Public Health
Summary:
Exposure to lead wreaks havoc in the brain, with consequences that include lower IQ and reduced potential for learning. But the precise mechanism by which lead alters nerve cells in the brain has largely remained unknown. New research has used high-powered fluorescent microscopy and other advanced techniques to painstakingly chart the varied ways lead inflicts its damage.

New research shows that lead interferes with the synthesis and function of BDNF, derailing the brain’s center for learning.
Credit: Image courtesy of Columbia University's Mailman School of Public Health

Exposure to lead wreaks havoc in the brain, with consequences that include lower IQ and reduced potential for learning. But the precise mechanism by which lead alters nerve cells in the brain has largely remained unknown.

New research led by Tomαs R. Guilarte, PhD, Chair of Environmental Health Sciences, and post-doctoral research scientist Kirstie H. Stansfield, PhD, used high-powered fluorescent microscopy and other advanced techniques to painstakingly chart the varied ways lead inflicts its damage. They focused on signaling pathways involved in the production of brain-derived neurotropic factor, or BDNF, a chemical critical to the creation of new synapses in the hippocampus, the brain's center for memory and learning.

The study appears online in the journal Toxicological Sciences.

Once BDNF is produced in the nucleus, explains Dr. Stansfield, it is transported as cargo in a railroad-car-like vesicle along a track called a microtubule toward sites of release in the axon and dendritic spines. Vesicle navigation is controlled in part through activation (phosphorylation) of the huntingtin protein, which as its name suggests, was first identified through research into Huntington's disease. By looking at huntington expression, the researchers found that lead exposure, even in small amounts, is likely to impede or reverse the train by altering phosphorylation at a specific amino acid.

The BDNF vesicle transport slowdown is just one of a variety of ways that lead impedes BDNF's function. The researchers also explored how lead curbs production of BDNF in the cell nucleus. One factor, they say, may be a protein called methyl CpG binding protein 2, or MeCP2, which has been linked with RETT syndrome and autism spectrum disorders and acts to "silence" BDNF gene transcription.

The paper provides the first comprehensive working model of the ways by which lead exposure impairs synapse development and function. "Lead attacks the most fundamental aspect of the brain -- the synapse. But by better understanding the numerous and complex ways this happens we will be better able to develop therapies that ameliorate the damage," says Dr. Guilarte.

Study co-authors include J. Richard Pilsner from the University of Massachusetts, Amherst; and Quan Lu and Robert O. Wright of the Harvard School of Public Health.

Funding was provided by the National Institute for Environmental Health Sciences.


Story Source:

The above story is based on materials provided by Columbia University's Mailman School of Public Health. Note: Materials may be edited for content and length.


Journal Reference:

  1. K. H. Stansfield, J. R. Pilsner, Q. Lu, R. O. Wright, T. R. Guilarte. Dysregulation of BDNF-TrkB signaling in developing hippocampal neurons by Pb2 Implications for an environmental basis of neurodevelopmental disorders. Toxicological Sciences, 2012; DOI: 10.1093/toxsci/kfs090

Cite This Page:

Columbia University's Mailman School of Public Health. "In what ways does lead damage the brain? It derails the brain's center for learning." ScienceDaily. ScienceDaily, 29 February 2012. <www.sciencedaily.com/releases/2012/02/120229105141.htm>.
Columbia University's Mailman School of Public Health. (2012, February 29). In what ways does lead damage the brain? It derails the brain's center for learning. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2012/02/120229105141.htm
Columbia University's Mailman School of Public Health. "In what ways does lead damage the brain? It derails the brain's center for learning." ScienceDaily. www.sciencedaily.com/releases/2012/02/120229105141.htm (accessed July 31, 2014).

Share This




More Mind & Brain News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dieting At A Young Age Might Lead To Harmful Health Habits

Dieting At A Young Age Might Lead To Harmful Health Habits

Newsy (July 30, 2014) — Researchers say women who diet at a young age are at greater risk of developing harmful health habits, including eating disorders and alcohol abuse. Video provided by Newsy
Powered by NewsLook.com
It's Not Just Facebook: OKCupid Experiments With Users Too

It's Not Just Facebook: OKCupid Experiments With Users Too

Newsy (July 29, 2014) — If you've been looking for love online, there's a chance somebody has been looking at how you're looking. Video provided by Newsy
Powered by NewsLook.com
How Your Face Can Leave A Good Or Bad First Impression

How Your Face Can Leave A Good Or Bad First Impression

Newsy (July 29, 2014) — Researchers have found certain facial features can make us seem more attractive or trustworthy. Video provided by Newsy
Powered by NewsLook.com
Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) — A new study shows sleep deprivation can make it harder for people to remember specific details of an event. 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