title: Transcranial Direct Current Stimulation Modulates Neurogenesis and Microglia Activation in the Mouse Brain.
abstract: Transcranial direct current stimulation (tDCS) has been suggested as an adjuvant tool to promote recovery of function after stroke, but the mechanisms of its action to date remain poorly understood. Moreover, studies aimed at unraveling those mechanisms have essentially been limited to the rat, where tDCS activates resident microglia as well as endogenous neural stem cells. Here we studied the effects of tDCS on microglia activation and neurogenesis in the mouse brain. Male wild-type mice were subjected to multisession tDCS of either anodal or cathodal polarity; sham-stimulated mice served as control. Activated microglia in the cerebral cortex and neuroblasts generated in the subventricular zone as the major neural stem cell niche were assessed immunohistochemically. Multisession tDCS at a sublesional charge density led to a polarity-dependent downregulation of the constitutive expression of Iba1 by microglia in the mouse cortex. In contrast, both anodal and, to an even greater extent, cathodal tDCS induced neurogenesis from the subventricular zone. Data suggest that tDCS elicits its action through multifacetted mechanisms, including immunomodulation and neurogenesis, and thus support the idea of using tDCS to induce regeneration and to promote recovery of function. Furthermore, data suggest that the effects of tDCS may be animal- and polarity-specific.
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany; Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany.
authors.forename: Anton
authors.initials: A
authors.lastname: Pikhovych
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany.
authors.forename: Nina Paloma
authors.initials: NP
authors.lastname: Stolberg
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany.
authors.forename: Lea
authors.initials: L
authors.lastname: Jessica Flitsch
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany; Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany.
authors.forename: Helene Luise
authors.initials: HL
authors.lastname: Walter
authors.affiliation: Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Graf
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, 52425 Juelich, Germany.
authors.forename: Gereon Rudolf
authors.initials: GR
authors.lastname: Fink
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany; Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, 52425 Juelich, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schroeter
authors.affiliation: Department of Neurology, University Hospital of Cologne, Kerpener Strasse 62, 50924 Cologne, Germany; Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Cognitive Neuroscience, Institute of Neuroscience and Medicine (INM-3), Research Centre Juelich, 52425 Juelich, Germany.
authors.forename: Maria Adele
authors.identifier: 0000-0001-8036-395X
authors.initials: MA
authors.lastname: Rueger