Hector J. Rosa, Karla M. Casillas, Loyda B. Méndez
Division of Science & Technology, Universidad Ana G. Méndez – Recinto de Carolina, Puerto Rico
Epidemiological studies have found associations between exposure to ambient particulate matter (PM) and adverse neurocognitive outcomes. Children are particularly vulnerable to the effects of ambient PM since their CNS is still in development, especially in regions related to executive functions, which develop significantly between the ages of 6 to 10 years. Toxicological studies have reported cognitive impairments, alteration in the levels of neurotransmitters, oxidative stress and neuroinflammatory responses in mice exposed to different types of PM. However, most studies have focused on prenatal, perinatal, and adult PM exposures. Therefore, the goal of this study was to assess if PM exposure impairs the postnatal development of executive function in an in-vivo model. To this extent, both female and male C57BL/6J mice (n=14/group) were exposed intranasally to either saline or increasing doses of diesel exhaust particles (DEP) during postnatal days (PND) 25 to 33. Neurocognitive processes were evaluated on PND36-38 with the Open Field Test and the Puzzle Box paradigm, which is a problem-solving test for screening general cognitive abilities and executive function in rodents. DEP exposure did not impair mice locomotion or exploratory behavior. However, mice exposed to DEP exhibited significantly higher latencies in problem-solving and short-term memory tasks, but not in long-term memory, when compared to controls. No sex related differences were observed. Thus, the results suggest DEP exposure specifically impairs the development of executive function related cognitive processes in juvenile mice.