Deborah Cory-Slechta, Ph.D.; Joshua Allen, Ph.D.
University of Rochester
NIEHS Grants R01ES021534, P30ES001247, T32ES007026
An NIEHS grantee and colleagues provide new insights into mechanisms by which early-life exposure to air pollution produces harmful brain changes in mice, including brain enlargement that is also seen in humans with autism and schizophrenia.
Exposure to air pollution has been linked with neurological and behavioral health effects in children and adults. To explore the biology involved, the researchers exposed mice to levels of ultrafine particles similar to what people might experience in mid-sized U.S. cities during rush hour. For two weeks after birth, the mice were exposed to four hours of polluted air a day for two four-day periods.
The researchers examined the brains of one group of mice 24 hours after the final pollution exposure. These mice all showed inflammation throughout the brain and had lateral brain ventricles two-to-three times larger than normal. As seen in autism and schizophrenia, the changes occurred predominately in males. The white matter normally surrounding the ventricles wasn’t fully developed, which the researchers attributed to damage from inflammation. The ventricles likely expanded to fill the space normally occupied by the white matter. The brain changes were also observed in mice examined 40 and 270 days after exposure, indicating that damage was permanent. The exposed mice performed poorly in tests of short-term memory, learning ability, and impulsivity. Brains of mice in all three groups also showed higher levels of the neurotransmitter glutamate, which is elevated in people with autism and schizophrenia.
Citation: Allen JL, Liu X, Pelkowski S, Palmer B, Conrad K, Oberdörster G, Weston D, Mayer-Pröschel M, Cory-Slechta DA. 2014. Early Postnatal Exposure to Ultrafine Particulate Matter Air Pollution: Persistent Ventriculomegaly, Neurochemical Disruption, and Glial Activation Preferentially in Male Mice. Environ Health Perspect; dx.doi.org/10.1289/ehp.1307984 [Online 5 June 2014].