Environmental enrichment that stimulates brain activity can reverse the long-term learning deficits caused by lead poisoning, according to a study conducted by researchers at the Johns Hopkins Bloomberg School of Public Health. It has long been known that lead poisoning in children affects their cognitive and behavioral development. Despite significant efforts to reduce lead contamination in homes, childhood lead poisoning remains a major public health problem with an estimated 34 million housing units in the United States containing lead paint. The Hopkins study is the first to demonstrate that the long-term deficits in cognitive function caused by lead can be reversed and offers a basis for the treatment of childhood lead intoxication. The findings appear in the online edition of the Annals of Neurology.
“Lead exposure during development causes long-lasting deficits in learning in experimental animals, but our study shows for the first time that these cognitive deficits are reversible,” said lead author Tomás R. Guilarte, PhD, professor of environmental health sciences at the Johns Hopkins Bloomberg School of Public Health. “This study is particularly important for two reasons. First, it was not known until now whether the effects of lead on cognitive function were reversible. Secondly, the environmental enrichment that reversed the learning deficits was administered after the animals were exposed to lead. Environmental enrichment could be a promising therapy for treating millions of children suffering from the effects of lead poisoning,” added Dr. Guilarte.
For their study, Dr. Guilarte, graduate student Christopher Toscano, research technologist Jennifer McGlothan, and research associate Shelley Weaver observed groups of lead–treated or non-treated (control) rats that were raised in an enriched environment. Enrichment cages were multi-level, containing toys, a running wheel, a hammock, platforms, tunnels, and housed multiple animals. Littermates to these rats were raised in standard-sized laboratory cages that the researchers designated as “isolated environment.” To measure the learning ability of rats in the various treatment groups, the researchers trained each rat to find a submerged, invisible platform in a pool of water, called the water maze. Each day of training, they timed how long each rat took to find the platform. They observed that both the lead-exposed and control rats living in the enriched environment learned to find the platform in 20 seconds or less within the four-day training period. The isolated control rats took longer to find the platform, while lead-exposed isolated rats took the longest and nearly 50 percent of them failed to learn the test by the last day of training.
Along with the enhanced learning performance of lead-exposed rats reared in an enriched environment, the researchers found a recovery in the levels of the NR1 subunit of the N-methyl-D-aspartate receptor (NMDAR) in the hippocampus. The NR1 subunit is obligatory for functional NMDAR and these researchers have previously shown that lead targets the NMDAR. The hippocampus is a brain region important for learning and memory and previous research has determined that the NR1 subunit is essential for learning performance in the water maze.
Tim Parsons | EurekAlert!
NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures
17.11.2017 | National Institute of Standards and Technology (NIST)
High speed video recording precisely measures blood cell velocity
15.11.2017 | ITMO University
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
20.11.2017 | Earth Sciences
20.11.2017 | Earth Sciences
20.11.2017 | Life Sciences