PI3Kδ inhibition reduces TNF secretion and neuroinflammation in a mouse cerebral stroke model

  • Nature Communications 5, Article number: 3450 (2014)
  • doi:10.1038/ncomms4450
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Stroke is a major cause of death worldwide and the leading cause of permanent disability. Although reperfusion is currently used as treatment, the restoration of blood flow following ischaemia elicits a profound inflammatory response mediated by proinflammatory cytokines such as tumour necrosis factor (TNF), exacerbating tissue damage and worsening the outcomes for stroke patients. Phosphoinositide 3-kinase delta (PI3Kδ) controls intracellular TNF trafficking in macrophages and therefore represents a prospective target to limit neuroinflammation. Here we show that PI3Kδ inhibition confers protection in ischaemia/reperfusion models of stroke. In vitro, restoration of glucose supply following an episode of glucose deprivation potentiates TNF secretion from primary microglia—an effect that is sensitive to PI3Kδ inhibition. In vivo, transient middle cerebral artery occlusion and reperfusion in kinase-dead PI3Kδ (p110δD910A/D910A) or wild-type mice pre- or post-treated with the PI3Kδ inhibitor CAL-101, leads to reduced TNF levels, decreased leukocyte infiltration, reduced infarct size and improved functional outcome. These data identify PI3Kδ as a potential therapeutic target in ischaemic stroke.

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We thank members of the Meunier and Arumugam laboratories for technical assistance, Geoffrey Osborne for his expertise support in flow cytometry, Rowan Tweedale for critical appraisal of this article and Shaun Jackson (Melbourne University) for the initial gift of IC87114. We also thank technical staff of The University of Queensland Biological Resources and Queensland Brain Institute animal facility for maintaining the mice (PI3Kδ transgenic and wild type) used in this study. The work was supported by a National Health and Medical Research Council of Australia (NHMRC) project Grant 1005964 (to F.A.M. and T.V.A.). M.J.R. is supported by a Career Development Fellowship from SpinalCure Australia, F.A.M. is a Senior Research Fellow of the NHMRC and T.V.A. was a Future Fellow of the Australian Research Council.

Author information

Author notes

    • Pei Ching Low
    •  & Silvia Manzanero

    These authors contributed equally to this work

    • Thiruma V. Arumugam

    Present address: Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore 117597, Singapore


  1. Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia

    • Pei Ching Low
    • , Nika Mohannak
    • , Vinod K. Narayana
    • , Tam H. Nguyen
    • , David Kvaskoff
    • , Marc J. Ruitenberg
    •  & Frédéric A. Meunier
  2. School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia

    • Silvia Manzanero
    • , Faith H. Brennan
    • , Marc J. Ruitenberg
    •  & Thiruma V. Arumugam
  3. Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany

    • Mathias Gelderblom
    •  & Tim Magnus
  4. Vascular Biology and Immunopharmacology Group, Department of Pharmacology, Monash University, Clayton, Victoria 3800, Australia

    • Hyun Ah Kim
    • , Brad R. S. Broughton
    •  & Christopher G. Sobey
  5. UCL Cancer Institute, Paul O'Gorman Building, University College London, 72 Huntley Street London WC1E 6DD, UK

    • Bart Vanhaesebroeck
  6. Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia

    • Jennifer L. Stow


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P.C.L., T.V.A., S.M. and F.A.M. conceived the study, designed the experiments and analysed the data. P.C.L and T.H.N. performed in vitro experiments; P.C.L., S.M. and N.M conducted immunohistochemistry, microscopy and analysis; T.V.A. and M.G. performed tMCAO and in vivo CAL-101 treatments; P.C.L. and M.G. carried out the FACS experiments and analysis. P.C.L. and N.M. performed all western blotting. F.H.B. and M.J.R. composed chimeras on which T.M., H.A.K., B.R.S.B. and C.S. performed stroke on. V.K.N. and D.K. carried out all mass spectrometry experiments. M.J.R., J.L.S., T.M., T.H.N. and B.V. provided intellectual expertise, analysed data and edited the manuscript. P.C.L., S.M., M.J.R., N.M., T.V.A. and F.A.M. wrote the manuscript. T.V.A. and F.A.M. supervised the study.

Competing interests

B.V. is a consultant for Activiomics (London, UK) and Karus Therapeutics (Oxford, UK). The remaining authors declare no competing financial interests.

Corresponding authors

Correspondence to Thiruma V. Arumugam or Frédéric A. Meunier.

Supplementary information

PDF files

  1. 1.

    Supplementary Figure

    Supplementary Figure 1


  1. 1.

    Supplementary Movie 1

    3D view through the ischemic penumbra of wild-type cerebral cortex by confocal imaging on cryosections stained for cell nuclei (white), Iba1-positive cells (green channel), and TNF (red channel).

  2. 2.

    Supplementary Movie 2

    3D view through the ischemic penumbra of CAL101-treated cerebral cortex by confocal imaging on cryosections stained for cell nuclei (white), Iba1-positive cells (green channel), and TNF (red channel).

  3. 3.

    Supplementary Movie 3

    3D view through the ischemic penumbra of wild-type cerebral cortex by confocal imaging on cryosections stained for cell nuclei (white), GFAP-positive astrocytes (red channel), and TNF (green channel).

  4. 4.

    Supplementary Movie 4

    3D view through the ischemic penumbra of CAL-101-treated cerebral cortex by confocal imaging on cryosections stained for cell nuclei (white), GFAP positive astrocytes (red channel), and TNF (green channel).


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