Nav: Home

In rats, perinatal exposure to phthalates impairs brain structure and function

July 18, 2018

CHAMPAIGN, Ill. -- Male and female rats exposed in the womb and during lactation to plasticizing chemicals known as phthalates had significantly fewer neurons and synapses than those that were not exposed, researchers report in a new study. The phthalate-exposed rats had reductions in the size of their medial prefrontal cortex, a brain region that regulates behavior, and showed deficits in cognitive flexibility.

The variety of phthalates and quantities used in the study were environmentally relevant to human exposures, said University of Illinois psychology professor Janice Juraska, who led the research.

"Phthalates are used as plasticizers in a variety of consumer goods, including plastics, personal care products, fragrances, pharmaceuticals, clothing and building materials," she said. "Contact with these products can lead to exposure through the skin, digestion or lungs."

Research has shown that phthalates readily cross the placenta to expose a developing fetus, and that they can be delivered to offspring via lactation, Juraska said. Because these chemicals can disrupt normal hormone signaling, their presence in infants and children is of special concern. The developing brain, in particular, is susceptible to hormone disruptions. Several studies in humans suggest that prenatal phthalate exposure may negatively affect children's behavior, their ability to regulate their own actions and the incidence of neuropsychiatric disorders, she said.

The pregnant rats in the study were each assigned to one of three groups - two of which were exposed to differing concentrations of phthalates during pregnancy and lactation, and one, a control group, that was not exposed at all. The researchers tested how well the offspring learned to use visual and textural cues to navigate a maze, and examined the relative development of their brains once they reached adulthood.

"We found that there was an appreciable reduction in the number of neurons, the number of synapses and the size of the medial prefrontal cortex in the phthalate-exposed rats," Juraska said. "They also showed a deficit in what we call cognitive flexibility. They made significantly more errors when navigating the mazes than rats that had not been exposed."

The negative effects of perinatal exposure to phthalates were seen at both doses of the phthalate mixture, the researchers report, which were "presumably within the range of the estimated daily intakes of humans."
-end-
Juraska is an affiliate of the Beckman Institute for Advanced Science and Technology at Illinois. The National Institute of Environmental Health Sciences and the U.S. Environmental Protection Agency supported this research.

University of Illinois at Urbana-Champaign

Related Neurons Articles:

New tool to identify and control neurons
One of the big challenges in the Neuroscience field is to understand how connections and communications trigger our behavior.
Neurons that regenerate, neurons that die
In a new study published in Neuron, investigators report on a transcription factor that they have found that can help certain neurons regenerate, while simultaneously killing others.
How neurons use crowdsourcing to make decisions
When many individual neurons collect data, how do they reach a unanimous decision?
Neurons can learn temporal patterns
Individual neurons can learn not only single responses to a particular signal, but also a series of reactions at precisely timed intervals.
A turbo engine for tracing neurons
Putting a turbo engine into an old car gives it an entirely new life -- suddenly it can go further, faster.
Brain neurons help keep track of time
Turning the theory of how the human brain perceives time on its head, a novel analysis in mice reveals that dopamine neuron activity plays a key role in judgment of time, slowing down the internal clock.
During infancy, neurons are still finding their places
Researchers have identified a large population of previously unrecognized young neurons that migrate in the human brain during the first few months of life, contributing to the expansion of the frontal lobe, a region important for social behavior and executive function.
How many types of neurons are there in the brain?
For decades, scientists have struggled to develop a comprehensive census of cell types in the brain.
Molecular body guards for neurons
In the brain, patterns of neural activity are perfectly balanced.
Engineering researchers use laser to 'weld' neurons
University of Alberta researchers have developed a method of connecting neurons, using ultrashort laser pulses -- a breakthrough technique that opens the door to new medical research and treatment opportunities.

Related Neurons Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".