Transcriptional expression patterns triggered by chemically distinct neuroprotective molecules.

TitleTranscriptional expression patterns triggered by chemically distinct neuroprotective molecules.
Publication TypeJournal Article
Year of Publication2012
AuthorsPappas DJ, Gabatto PA, Oksenberg D, Khankhanian P, Baranzini SE, Gan L, Oksenberg JR
Date Published2012 Dec 13
KeywordsAnimals, Calcium, Cell Adhesion, Cell Survival, Cerebral Cortex, Data Mining, Gene Library, Genome-Wide Association Study, Glutamic Acid, Hypoxia-Inducible Factor 1, Mice, Mitogen-Activated Protein Kinases, Neurons, Neuroprotective Agents, Real-Time Polymerase Chain Reaction, Receptors, N-Methyl-D-Aspartate, RNA Interference, Signal Transduction, Toll-Like Receptors, Transcription, Genetic, Transcriptome

Glutamate-mediated excitotoxicity has been purported to underlie many neurodegenerative disorders. A subtype of glutamate receptors, namely N-methyl-d-aspartate (NMDA) receptors, has been recognized as potential targets for neuroprotection. To increase our understanding of the mechanisms that underlie this neuroprotection, we employed a mouse model of glutamate receptor-induced excitotoxic injury. Primary cortical neurons derived from postnatal day-0 CD-1 mice were cultured in the presence or absence of neuroprotective molecules and exposed to NMDA. Following a recovery period, whole genome expression was measured by microarray analysis. We used a combination of database and text mining, as well as systems modeling to identify signatures within the differentially expressed genes. While molecules differed in their mechanisms of action, we found significant overlap in the expression of a core group of genes and pathways. Many of these molecules have clear links to neuronal protection and survival, including ion channels, transporters, as well as signaling pathways including the mitogen-activated protein kinase (MAPK), the Toll-like receptor (TLR), and the hypoxic inducible factor (HIF). Within the TLR pathway, we also discovered a significant enrichment of interferon regulatory factor 7 (IRF7)-regulated genes. Knockdown of Irf7 by RNA interference resulted in reduced survival following NMDA treatment. Given the prominent role that IRF7 plays in the transduction of type-I interferons (IFNs), we also tested whether type-I IFNs alone functioned as neuroprotective agents and found that type-I IFNs were sufficient to promote neuronal survival. Our data suggest that the TLR/IRF7/IFN axis plays a significant role in recovery from glutamate-induced excitotoxicity.

Alternate JournalNeuroscience
PubMed ID22986168
PubMed Central IDPMC3489981
Grant ListR01 AG036884 / AG / NIA NIH HHS / United States
R01 NS026799 / NS / NINDS NIH HHS / United States
R01NS26799 / NS / NINDS NIH HHS / United States