E-GEOD-55627 - Microglial response to Aβ and prostaglandin-E2 EP4 receptor activation
Released on 25 April 2014, last updated on 6 May 2014
A persistent and non-resolving inflammatory response to accumulating Aβ peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating Aβ peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many pro-inflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing Aβ-induced inflammation represent a relatively unexplored area. Here we hypothesized that signaling through the prostaglandin-E2 (PGE2) EP4 receptor potently suppresses microglial inflammatory responses to Aβ42 peptides. In cultured microglial cells, EP4 stimulation attenuated levels of Aβ42-induced inflammatory factors and potentiated phagocytosis of Aβ42. Microarray analysis was performed and demonstrated that EP4 stimulation broadly opposed Aβ42-driven gene expression changes in microglia, with enrichment for targets of IRF1, IRF7, and NF-κB transcription factors. Primary microglia were isolated from the brains of postnatal day 7 C57BL/6J mouse pups using the Neural Tissue Dissociation Kit (P), MACS Separation Columns (LS), and magnetic CD11b Microbeads from Miltenyi Biotec (Auburn, CA). Microglia from three separate litters of pups were maintained as three independent biological replicates for each treatment. After being cultured for three days, microglia were treated with oligomeric Aβ42 (10uM) and/or the specific EP4 agonist AE1-329 (100nM) for 6 hours. These 4 treatment conditions (Aβ + AE1, Aβ alone, AE1 alone, and vehicle alone) and 3 independent biological replicates per treatment gave us 12 total samples. After 6 hours of treatment, RNA was isolated from the microglia for microarray analysis.
transcription profiling by array
Katrin Andreasson <email@example.com>, Katrin I Andreasson, Nathaniel S Woodling
Suppression of Alzheimer-Associated Inflammation by Microglial Prostaglandin-E2 EP4 Receptor Signaling. Woodling NS, Wang Q, Priyam PG, Larkin P, Shi J, Johansson JU, Zagol-Ikapitte I, Boutaud O, Andreasson KI. , Europe PMC 24760848