title: P2X4 receptor regulates alcohol-induced responses in microglia.
abstract: Mounting evidence indicates that alcohol-induced neuropathology may result from multicellular responses in which microglia cells play a prominent role. Purinergic receptor signaling plays a key role in regulating microglial function and, more importantly, mediates alcohol-induced effects. Our findings demonstrate that alcohol increases expression of P2X4 receptor (P2X4R), which alters the function of microglia, including calcium mobilization, migration and phagocytosis. Our results show a significant up-regulation of P2X4 gene expression as analyzed by real-time qPCR (***p < 0.002) and protein expression as analyzed by flow cytometry (**p < 0.004) in embryonic stem cell-derived microglial cells (ESdM) after 48 hours of alcohol treatment, as compared to untreated controls. Calcium mobilization in ethanol treated ESdM cells was found to be P2X4R dependent using 5-BDBD, a P2X4R selective antagonist. Alcohol decreased migration of microglia towards fractalkine (CX3CL1) by 75 % following 48 h of treatment compared to control (***p < 0.001). CX3CL1-dependent migration was confirmed to be P2X4 receptor-dependent using the antagonist 5-BDBD, which reversed the effects as compared to alcohol alone (***p < 0.001). Similarly, 48 h of alcohol treatment significantly decreased phagocytosis of microglia by 15 % compared to control (*p < 0.05). 5-BDBD pre-treatment prior to alcohol treatment significantly increased microglial phagocytosis (***p < 0.001). Blocking P2X4R signaling with 5-BDBD decreased the level of calcium mobilization compared to ethanol treatment alone. These findings demonstrate that P2X4 receptor may play a role in modulating microglial function in the context of alcohol abuse.
authors.affiliation: Department of Pathology and Laboratory Medicine, Temple University School of Medicine, 3500 N. Broad Street, MERB 845A, Philadelphia, PA, 19140, USA.
authors.forename: Larisa
authors.initials: L
authors.lastname: Gofman
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Cenna
authors.forename: Raghava
authors.initials: R
authors.lastname: Potula
mesh_terms: D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D000431:Ethanol / Q000494:pharmacology*; D006801:Humans; D017628:Microglia / Q000187:drug effects* / Q000502:physiology*; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology; D058848:Receptors, Purinergic P2X4 / Q000502:physiology*
chemical_list: D058848:Receptors, Purinergic P2X4; D000431:Ethanol