Prolonged, Low-Level Exposure to the Marine Toxin, Domoic Acid, and Measures of Neurotoxicity in Nonhuman Primates
Rebekah Petroff, Christopher Williams, Jian‐Liang Li, James W. MacDonald, Theo K. Bammler, Todd L. Richards, Christopher N. English, Audrey Baldessari, Sara Shum, Jing Jing, Nina Isoherranen, Brenda Crouthamel, Noelle McKain, Kimberly S. Grant, Thomas M. Burbacher, G. Jean Harry
Abstract
BACKGROUND: ). At these levels, cognitive effects occur in the absence of acute symptoms or evidence of neuronal death. OBJECTIVES: monkeys. METHODS: for an average of 14 months. Clinical blood counts, chemistry, and cytokine levels were analyzed in the blood. In-life magnetic resonance (MR) imaging assessed volumetric and tractography differences in and between the hippocampus and thalamus. Histology of neurons and glia in the fornix, fimbria, internal capsule, thalamus, and hippocampus was evaluated. Hippocampal RNA sequencing was used to identify differentially expressed genes. Enrichment of gene networks for neuronal health, excitotoxicity, inflammation/glia, and myelin were assessed with Gene Set Enrichment Analysis. RESULTS: response showed no indication of astrocyte hypertrophy. DISCUSSION: monkeys to environmentally relevant levels of DA suggested a subtle shift in the molecular profile of the hippocampus and the microglia phenotype in the thalamus that was possibly reflective of an adaptive response due to prolonged DA exposure. https://doi.org/10.1289/EHP10923.