title: TRPM7 regulates proliferation and polarisation of macrophages.
abstract: Ion channels play pivotal roles in regulating important functions of macrophages, such as cytokine and chemokine production, migration, proliferation, phagocytosis and others. In this study, we have identified the transient receptor potential cation channel, subfamily M, member 7 (TRPM7) for the first time in macrophages. TRPM7 activity is differentially regulated in macrophages, i.e. current density in TRPM7 is significantly larger in anti-inflammatory M2-type macrophages than in untreated and in pro-inflammatory M1-type macrophages, whereas mRNA levels of TRPM7 remain unchanged upon cell polarisation. The specific TRPM7 inhibitors NS8593 and FTY720 abolish proliferation of macrophages induced by interleukin-4 (IL-4) and macrophage colony-stimulating factor (M-CSF), respectively, whereas proliferation arrest was not accompanied by induction of apoptosis or necrosis in macrophages. Furthermore, NS8593 and FTY720 prevented polarisation of macrophages towards the anti-inflammatory M2 phenotype. Inhibition of TRPM7 reduced IL-4-induced upregulation of arginase-1 (Arg1) mRNA levels and Arg1 activity, and abolished the inhibitory effects of IL-4 or M-CSF on LPS-induced TNF-α production by macrophages. In summary, our data suggest a main role of TRPM7 in the regulation of macrophage proliferation and polarisation.
authors.affiliation: Infection and Immunity Research Institute, St George's, University of London, London SW17 0RE, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Schilling
authors.affiliation: Cardiovascular and Cell Sciences Research Institute, St George's, University of London, London SW17 0RE, UK Institute for Medical and Biomedical Education, St. George's, University of London, London SW17 0RE, UK.
authors.forename: Francesc
authors.initials: F
authors.lastname: Miralles
authors.affiliation: Infection and Immunity Research Institute, St George's, University of London, London SW17 0RE, UK ceder@sgul.ac.uk.
authors.forename: Claudia
authors.initials: C
authors.lastname: Eder
mesh_terms: D015057:1-Naphthylamine / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D016764:Cell Polarity / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D004594:Electrophysiology; D000068876:Fingolimod Hydrochloride; D015847:Interleukin-4 / Q000494:pharmacology; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D011409:Propylene Glycols / Q000494:pharmacology; D013110:Sphingosine / Q000031:analogs & derivatives / Q000494:pharmacology; D050053:TRPM Cation Channels / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: C515166:(R)-N-(benzimidazol-2-yl)-1,2,3,4-tetrahydro-1-naphthylamine; D011409:Propylene Glycols; D050053:TRPM Cation Channels; D014409:Tumor Necrosis Factor-alpha; D015847:Interleukin-4; D016173:Macrophage Colony-Stimulating Factor; D015057:1-Naphthylamine; C421903:Trpm7 protein, mouse; D000068876:Fingolimod Hydrochloride; D013110:Sphingosine
keywords: Ion channel; Macrophage; Polarisation; Proliferation; TRP channel; Transient receptor potential channel