Pretreatment of aripiprazole and minocycline, but not haloperidol, suppresses oligodendrocyte damage from interferon-γ-stimulated microglia in co-culture model

https://doi.org/10.1016/j.schres.2013.09.011Get rights and content

Abstract

Recent imaging studies have indicated that the pathophysiology of schizophrenia is closely related to white matter abnormalities and microglial activation. Additionally, recent clinical trials have suggested that atypical antipsychotics may have brain protective properties and that minocycline, an antibiotic with inhibitory effects on microglial activation, improves symptoms of schizophrenia. We have reported that not only atypical antipsychotics with dopamine D2 receptor (D2R) antagonism but also aripiprazole, a unique antipsychotic drug with D2R partial agonism, inhibit microglial activation in vitro. Thus, atypical antipsychotics may exert a beneficial influence on both microglia and oligodendrocytes, while the underlying mechanisms have not been clarified. Here, we investigated whether antipsychotics suppress oligodendrocyte damage by inhibiting microglial activation utilizing a co-culture model with microglia and oligodendrocytes. Pretreatment of aripiprazole and minocycline suppressed apoptosis of oligodendrocytes in the co-culture model with interferon-γ (IFN-γ)-activated microglia, while haloperidol, a traditional antipsychotic drug, did not. Aripiprazole and minocycline inhibited the production of tumor necrosis factor-alpha (TNF-α) from IFN-γ-activated microglia. Moreover, aripiprazole and minocycline attenuated the phosphorylation of signal transducer and activator of transcription 1 (STAT1) in microglia. Overall, our results suggest that aripiprazole and minocycline may have antipsychotic effects through reducing oligodendrocyte damage caused by microglial activation. These results put forward a novel therapeutic hypothesis in schizophrenia research. Future in vivo studies to confirm the present results should be performed.

Introduction

Multiple theories have been put forth regarding the pathogenesis of schizophrenia, while the underlying mechanisms remain to be identified (Fatemi and Folsom, 2009, Jaaro-Peled et al., 2009). Recent imaging studies have shown that first-episode schizophrenia patients have a significant volume reduction in white matter with abnormal brain connectivity (Price et al., 2006, Schlosser et al., 2007). Deviant myelination of schizophrenia patients has been evident in postmortem studies (Uranova et al., 2004, Uranova et al., 2007, Bernstein et al., 2009) and imaging studies (Miyata et al., 2009, Kubota et al., 2011, Kubota et al., 2013). Combined with evidence of dysregulation of myelination-related genes, a disruption of oligodendrocyte function in schizophrenia has been strongly implicated (McCullumsmith et al., 2007).

Mittelbronn et al. demonstrated that local distribution of microglia in the normal adult human brain differs by up to one order of magnitude and that there is significantly more microglia in white matter than in gray matter (Mittelbronn et al., 2001). Therefore, microglial activation plays an important role especially in white matter disorders (Schnieder and Dwork, 2011). Microglial cytotoxicity of oligodendrocytes is mediated through free radical-related molecules (nitric oxide (NO) and/or peroxynitrite) and pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) (Buntinx et al., 2004, Steelman and Li, 2011). TNF-α is known to compromise the growth of oligodendrocytes and the expression of mRNA for myelin basic protein (MBP) in cultures (Cammer and Zhang, 1999). Furthermore, TNF-α is reported to inhibit the survival and proliferation of oligodendrocyte progenitors and their subsequent differentiation into mature myelinating phenotypes (Feldhaus et al., 2004). Recent postmortem and imaging studies have suggested the microglial activation (Radewicz et al., 2000, Steiner et al., 2006, Steiner et al., 2008c, van Berckel et al., 2008, Doorduin et al., 2009, Takano et al., 2010) and oligodendrocyte dysfunction (Uranova et al., 2004, Uranova et al., 2007, Bernstein et al., 2009) in schizophrenia patients. Based on the above evidence, microglial activation may be involved in the pathological process of schizophrenia by damaging oligodendrocytes.

Various antipsychotics, which had classically been regarded to modulate solely neurons and synaptic networks, have recently been revealed to have direct anti-inflammatory properties on activated microglia from a series of in vitro studies (Kato et al., 2007, Kato et al., 2011a, Kato et al., 2013). We have reported that not only antipsychotics with dopamine D2 receptor (D2R) antagonism but also aripiprazole with D2R partial agonism inhibit microglial activation in vitro (Kato et al., 2008, Kato et al., 2011b). In spite of a different pharmacological profile, aripiprazole is effective against the positive and negative symptoms of patients with schizophrenia like other antipsychotics with lower side effects (Kasper et al., 2003, Potkin et al., 2003, Tandon et al., 2006). In addition, aripiprazole has been proved to be effective not only for schizophrenia but also for other psychiatric disorders such as major depressive disorders and bipolar disorders (Keck et al., 2006, Berman et al., 2007). On the other hand, minocycline, a semi-synthetic tetracycline antibiotic, is known to be one of the most well-known inhibitors of microglial activation (Yrjanheikki et al., 1998, Du et al., 2001). Minocycline, which can easily cross the blood–brain barrier, has been reported to provide neuroprotection via suppressing microglial activation in a number of neuronal disorders including amyotrophic lateral sclerosis (ALS), Parkinson's disease, Huntington's disease and Alzheimer's disease (Kriz et al., 2002, Van Den Bosch et al., 2002, Plane et al., 2010). Recent studies using animal models of schizophrenia have suggested that minocycline can be beneficial for the treatment of schizophrenia (Zhang et al., 2007, Fujita et al., 2008, Mizoguchi et al., 2008, Levkovitz et al., 2010). Furthermore, therapeutic improvement in psychotic symptoms has been demonstrated by minocycline in patients with schizophrenia (Ahuja and Carroll, 2007, Miyaoka et al., 2007, Miyaoka, 2008, Chaves et al., 2010, Levkovitz et al., 2010, Kelly et al., 2011, Chaudhry et al., 2012).

To the best of our knowledge, the protective effects of antipsychotics and minocycline on oligodendrocytes via the modulation of microglial inflammatory responses have never been reported. Our previous investigations have suggested that aripiprazole is the most effective antipsychotic, which directly and significantly inhibits microglial activation in vitro (Kato et al., 2008, Kato et al., 2011b). In the present study, we thus investigate the underlying mechanism of how aripiprazole, haloperidol and minocycline affect the degenerative process of oligodendrocytes via the modulation of microglial activation utilizing a co-culture model with microglia and oligodendrocytes.

Section snippets

Materials and methods

All experimental procedures were conducted in accordance with the Standard Guidelines for Animal Experiments of the Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.

Cell viability

In the present experiments, the cell viability of HAPI microglial cells was not affected by aripiprazole (20 μM), haloperidol (20 μM) and minocycline (10 μM) (data not shown). Therefore, we used these drugs under this concentration in the present study.

Protective effects of minocycline and antipsychotics on oligodendrocyte damage

IFN-γ is a typical Th1 cytokine and a major immuno-activator released by infiltrating T cells as well as activated microglia in the CNS (Kawanokuchi et al., 2006). Elevated mRNA levels of IFN-γ have been reported in the brain of schizophrenia

Discussion

This is the first report to demonstrate that pretreatment of aripiprazole and minocycline inhibits oligodendrocyte damage by suppressing IFN-γ-activated microglial cells.

We have already demonstrated that aripiprazole inhibits TNF-α production from IFN-γ-activated microglial cells via suppressing the elevation of intracellular calcium signaling, not via D2R receptor-related signaling (Kato et al., 2008). In the present study, we have proved that aripiprazole and minocycline have the potential to

Role of funding source

This work was financially supported by Grant-in-Aids from the Japan Society for the Promotion of Science (JSPS) [to YS, TAK, AM, YM and SK], and from the Mitsubishi Pharma Research Foundation [to TAK and HH].

Contributors

All authors contributed substantially to the scientific process leading up to the writing of the present paper. TAK and AM, the principal investigators of the present research, and YS, the first author, made the conception and design of the project and wrote the protocol. The performance of experiments and the data analysis/interpretation were done by YS, TAK, AM, YM, HH and MSK. YS wrote the first draft of the manuscript. Critical revisions of the manuscript were made by TAK, AM, DY and SK.

Conflict of interest

All authors declare that they have no financial conflict of interest.

Acknowledgments

The authors would like to thank Dr. Masahiro Ohgidani, Dr. Noriaki Sagata, Dr. Yusuke Yamauchi, and Dr. Kohei Hayakawa (Molecular & Translational Psychiatry Unit, Department of Neuropsychiatry, Kyushu University) and Dr. Daichi Muratsu (Division of Oral and Maxillofacial Oncology, Faculty of Dental Science, Kyushu University) for fruitful comments and technical supports.

References (84)

  • O. Freudenreich et al.

    Analysis of peripheral immune activation in schizophrenia using quantitative reverse-transcription polymerase chain reaction (RT-PCR)

    Psychiatry Res.

    (2010)
  • Y. Fujita et al.

    Phencyclidine-induced cognitive deficits in mice are improved by subsequent subchronic administration of the antibiotic drug minocycline

    Prog. Neuropsychopharmacol. Biol. Psychiatry

    (2008)
  • D.J. Gough et al.

    IFNgamma signaling — does it mean JAK-STAT?

    Cytokine Growth Factor Rev.

    (2008)
  • H. Jaaro-Peled et al.

    Neurodevelopmental mechanisms of schizophrenia: understanding disturbed postnatal brain maturation through neuregulin-1-ErbB4 and DISC1

    Trends Neurosci.

    (2009)
  • T. Kato et al.

    Risperidone significantly inhibits interferon-gamma-induced microglial activation in vitro

    Schizophr. Res.

    (2007)
  • T.A. Kato et al.

    Aripiprazole inhibits superoxide generation from phorbol-myristate-acetate (PMA)-stimulated microglia in vitro: implication for antioxidative psychotropic actions via microglia

    Schizophr. Res.

    (2011)
  • D.L. Kelly et al.

    Adjunct minocycline to clozapine treated patients with persistent schizophrenia symptoms

    Schizophr. Res.

    (2011)
  • Y.K. Kim et al.

    Th1, Th2 and Th3 cytokine alteration in schizophrenia

    Prog. Neuropsychopharmacol. Biol. Psychiatry

    (2004)
  • J. Kriz et al.

    Minocycline slows disease progression in a mouse model of amyotrophic lateral sclerosis

    Neurobiol. Dis.

    (2002)
  • M. Kubota et al.

    Age-related cortical thinning in schizophrenia

    Schizophr. Res.

    (2011)
  • R.E. McCullumsmith et al.

    Expression of transcripts for myelination-related genes in the anterior cingulate cortex in schizophrenia

    Schizophr. Res.

    (2007)
  • T. Miyaoka et al.

    Possible antipsychotic effects of minocycline in patients with schizophrenia

    Prog. Neuropsychopharmacol. Biol. Psychiatry

    (2007)
  • J. Miyata et al.

    Reduced white matter integrity correlated with cortico-subcortical gray matter deficits in schizophrenia

    Schizophr. Res.

    (2009)
  • M. Nikodemova et al.

    Minocycline down-regulates MHC II expression in microglia and macrophages through inhibition of IRF-1 and protein kinase C (PKC)alpha/beta II

    J. Biol. Chem.

    (2007)
  • S. Renaud et al.

    Gene expression profiling in chronic inflammatory demyelinating polyneuropathy

    J. Neuroimmunol.

    (2005)
  • K. Rutault et al.

    Combinations of ERK and p38 MAPK inhibitors ablate tumor necrosis factor-alpha (TNF-alpha) mRNA induction. Evidence for selective destabilization of TNF-alpha transcripts

    J. Biol. Chem.

    (2001)
  • R.G. Schlosser et al.

    White matter abnormalities and brain activation in schizophrenia: a combined DTI and fMRI study

    Schizophr. Res.

    (2007)
  • T.P. Schnieder et al.

    Searching for neuropathology: gliosis in schizophrenia

    Biol. Psychiatry

    (2011)
  • J. Steiner et al.

    S100B-immunopositive glia is elevated in paranoid as compared to residual schizophrenia: a morphometric study

    J. Psychiatr. Res.

    (2008)
  • J. Steiner et al.

    S100B is expressed in, and released from, OLN-93 oligodendrocytes: influence of serum and glucose deprivation

    Neuroscience

    (2008)
  • J. Steiner et al.

    Immunological aspects in the neurobiology of suicide: elevated microglial density in schizophrenia and depression is associated with suicide

    J. Psychiatr. Res.

    (2008)
  • J. Steiner et al.

    A new pathophysiological aspect of S100B in schizophrenia: potential regulation of S100B by its scavenger soluble RAGE

    Biol. Psychiatry

    (2009)
  • R. Tandon et al.

    A prospective, multicenter, randomized, parallel-group, open-label study of aripiprazole in the management of patients with schizophrenia or schizoaffective disorder in general psychiatric practice: Broad Effectiveness Trial With Aripiprazole (BETA)

    Schizophr. Res.

    (2006)
  • N.A. Uranova et al.

    Oligodendroglial density in the prefrontal cortex in schizophrenia and mood disorders: a study from the Stanley Neuropathology Consortium

    Schizophr. Res.

    (2004)
  • B.N. van Berckel et al.

    Microglia activation in recent-onset schizophrenia: a quantitative (R)-[11C]PK11195 positron emission tomography study

    Biol. Psychiatry

    (2008)
  • R.H. Woodruff et al.

    Oligodendrocyte development in the spinal cord and telencephalon: common themes and new perspectives

    Int. J. Dev. Neurosci.

    (2001)
  • Y. Zhang et al.

    Quetiapine alleviates the cuprizone-induced white matter pathology in the brain of C57BL/6 mouse

    Schizophr. Res.

    (2008)
  • R.M. Berman et al.

    The efficacy and safety of aripiprazole as adjunctive therapy in major depressive disorder: a multicenter, randomized, double-blind, placebo-controlled study

    J. Clin. Psychiatry

    (2007)
  • H.G. Bernstein et al.

    Glial cells in schizophrenia: pathophysiological significance and possible consequences for therapy

    Expert. Rev. Neurother.

    (2009)
  • M. Buntinx et al.

    Cytokine-induced cell death in human oligodendroglial cell lines. II: alterations in gene expression induced by interferon-gamma and tumor necrosis factor-alpha

    J. Neurosci. Res.

    (2004)
  • I.B. Chaudhry et al.

    Minocycline benefits negative symptoms in early schizophrenia: a randomised double-blind placebo-controlled clinical trial in patients on standard treatment

    J. Psychopharmacol.

    (2012)
  • P. Cheepsunthorn et al.

    Characterization of a novel brain-derived microglial cell line isolated from neonatal rat brain

    Glia

    (2001)
  • Cited by (68)

    • Neuroinflammation as a potential therapeutic target in neuroimmunological diseases

      2023, Translational Neuroimmunology: Neuroinflammation: Volume 7
    • Microglia increase tight-junction permeability in coordination with Müller cells under hypoxic condition in an in vitro model of inner blood-retinal barrier

      2021, Experimental Eye Research
      Citation Excerpt :

      In hypoxic condition, the resting microglia with a ramified morphology are transformed into activated microglia (Kettenmann et al., 2011), and subsequently, produce proinflammatory cytokines such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, which provoke the increase in TJ permeability (Dudvarski Stankovic et al., 2016). Due to multiple effects on vessels and neurons, microglia are considered as a new therapeutic target for CNS diseases (Seki et al., 2013; Wes et al., 2016). Müller cells (MCs), the most common type of glial cell found in the retina, possess a wide range of functions and are vital for the maintenance of TJ (Bai et al., 2009; Pierce et al., 1995; Reichenbach and Bringmann, 2013; Vecino et al., 2016).

    View all citing articles on Scopus
    View full text