1. ¹Molecular Neuroscience Unit, Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
2. ²Gene Expression and Genomics Unit, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA

Correspondence: Dr F Bosetti, Molecular Neuroscience Unit, Brain Physiology and Metabolism Section, National Institute on Aging/National Institutes of Health, 9 Memorial Drive, Bethesda, MD 20892-0947, USA. E-mail: frances@mail.nih.gov

³These authors contributed equally to this work.

Received 1 August 2008; Revised 5 September 2008; Accepted 7 October 2008; Published online 28 October 2008.

Abstract

Neuroinflammation plays a role in the progression of several neurodegenerative disorders. We used a lipopolysaccharide (LPS) model of neuroinflammation to characterize the gene expression changes underlying the inflammatory and behavioral effects of neuroinflammation. A single intracerebroventricular injection of LPS (5 g) was administered into the lateral ventricle of mice and, 24 h later, we examined gene expression in the cerebral cortex and hippocampus using microarray technology. Gene Ontology (GO) terms for inflammation and the ribosome were significantly enriched by LPS, whereas GO terms associated with learning and memory had decreased expression. We detected 224 changed transcripts in the cerebral cortex and 170 in the hippocampus. Expression of Egr1 (also known as Zif268) and Arc, two genes associated with learning and memory, was significantly lower in the cortex, but not in the hippocampus, of LPS-treated animals. Overall, altered expression of these genes may underlie some of the inflammatory and behavioral effects of neuroinflammation.