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Caspase signalling controls microglia activation and neurotoxicity

Abstract

Activation of microglia and inflammation-mediated neurotoxicity are suggested to play a decisive role in the pathogenesis of several neurodegenerative disorders. Activated microglia release pro-inflammatory factors that may be neurotoxic. Here we show that the orderly activation of caspase-8 and caspase-3/7, known executioners of apoptotic cell death, regulate microglia activation through a protein kinase C (PKC)-δ-dependent pathway. We find that stimulation of microglia with various inflammogens activates caspase-8 and caspase-3/7 in microglia without triggering cell death in vitro and in vivo. Knockdown or chemical inhibition of each of these caspases hindered microglia activation and consequently reduced neurotoxicity. We observe that these caspases are activated in microglia in the ventral mesencephalon of Parkinson’s disease (PD) and the frontal cortex of individuals with Alzheimer’s disease (AD). Taken together, we show that caspase-8 and caspase-3/7 are involved in regulating microglia activation. We conclude that inhibition of these caspases could be neuroprotective by targeting the microglia rather than the neurons themselves.

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Figure 1: LPS-induced DEVDase activity regulates microglia activation but not cell death.
Figure 2: Knockdown of caspase-3 or caspase-7 decreases microglia activation in response to LPS.
Figure 3: Caspase-8 activity controls LPS-induced caspase-3/7 activation.
Figure 4: Caspase-3/7 regulates microglia activation through the PKC-δ pathway.
Figure 5: In vivo inhibition of the caspase-dependent pathways prevents microglia activation.
Figure 6: Activation of caspase-3 and caspase-8 in microglia in brain from individuals with PD and AD.

References

  1. Hanisch, U. K. & Kettenmann, H. Microglia: active sensor and versatile effector cells in the normal and pathologic brain. Nature Neurosci. 10, 1387–1394 (2007)

    Article  CAS  Google Scholar 

  2. Block, M. L., Zecca, L. & Hong, J. S. Microglia-mediated neurotoxicity: uncovering the molecular mechanisms. Nature Rev. Neurosci. 8, 57–69 (2007)

    Article  CAS  Google Scholar 

  3. Chao, C. C., Hu, S., Molitor, T. W., Shaskan, E. G. & Peterson, P. K. Activated microglia mediate neuronal cell injury via a nitric oxide mechanism. J. Immunol. 149, 2736–2741 (1992)

    CAS  PubMed  Google Scholar 

  4. Castano, A., Herrera, A. J., Cano, J. & Machado, A. Lipopolysaccharide intranigral injection induces inflammatory reaction and damage in nigrostriatal dopaminergic system. J. Neurochem. 70, 1584–1592 (1998)

    Article  CAS  Google Scholar 

  5. Saijo, K. et al. A Nurr1/CoREST pathway in microglia and astrocytes protects dopaminergic neurons from inflammation-induced death. Cell 137, 47–59 (2009)

    Article  CAS  Google Scholar 

  6. Zhao, J. et al. IRF-8/interferon (IFN) consensus sequence-binding protein is involved in Toll-like receptor (TLR) signaling and contributes to the cross-talk between TLR and IFN-gamma signaling pathways. J. Biol. Chem. 281, 10073–10080 (2006)

    Article  CAS  Google Scholar 

  7. Car, B. D. et al. Interferon gamma receptor deficient mice are resistant to endotoxic shock. J. Exp. Med. 179, 1437–1444 (1994)

    Article  CAS  Google Scholar 

  8. Jin, J. J., Kim, H. D., Maxwell, J. A., Li, L. & Fukuchi, K. Toll-like receptor 4-dependent upregulation of cytokines in a transgenic mouse model of Alzheimer’s disease. J. Neuroinflammation 5, 23 (2008)

    Article  Google Scholar 

  9. Balistreri, C. R. et al. Association between the polymorphisms of TLR4 and CD14 genes and Alzheimer’s disease. Curr. Pharm. Des. 14, 2672–2677 (2008)

    Article  CAS  Google Scholar 

  10. Walter, S. et al. Role of the toll-like receptor 4 in neuroinflammation in Alzheimer’s disease. Cell. Physiol. Biochem. 20, 947–956 (2007)

    Article  CAS  Google Scholar 

  11. Nicholson, D. W. et al. Identification and inhibition of the ICE/CED-3 protease necessary for mammalian apoptosis. Nature 376, 37–43 (1995)

    Article  ADS  CAS  Google Scholar 

  12. Cohen, G. M. Caspases: the executioners of apoptosis. Biochem. J. 326, 1–16 (1997)

    Article  CAS  Google Scholar 

  13. Keller, M., Ruegg, A., Werner, S. & Beer, H. D. Active caspase-1 is a regulator of unconventional protein secretion. Cell 132, 818–831 (2008)

    Article  CAS  Google Scholar 

  14. Schulz, J. B. et al. Extended therapeutic window for caspase inhibition and synergy with MK-801 in the treatment of cerebral histotoxic hypoxia. Cell Death Differ. 5, 847–857 (1998)

    Article  ADS  CAS  Google Scholar 

  15. Braun, J. S. et al. Neuroprotection by a caspase inhibitor in acute bacterial meningitis. Nature Med. 5, 298–302 (1999)

    Article  CAS  Google Scholar 

  16. Cutillas, B., Espejo, M., Gil, J., Ferrer, I. & Ambrosio, S. Caspase inhibition protects nigral neurons against 6-OHDA-induced retrograde degeneration. Neuroreport 10, 2605–2608 (1999)

    Article  CAS  Google Scholar 

  17. Depino, A. M. et al. Microglial activation with atypical proinflammatory cytokine expression in a rat model of Parkinson’s disease. Eur. J. Neurosci. 18, 2731–2742 (2003)

    Article  Google Scholar 

  18. Kawai, T. & Akira, S. Signaling to NF-κB by Toll-like receptors. Trends Mol. Med. 13, 460–469 (2007)

    Article  CAS  Google Scholar 

  19. Gibbons, H. M. & Dragunow, M. Microglia induce neural cell death via a proximity-dependent mechanism involving nitric oxide. Brain Res. 1084, 1–15 (2006)

    Article  CAS  Google Scholar 

  20. Schumann, R. R. et al. Lipopolysaccharide activates caspase-1 (interleukin-1-converting enzyme) in cultured monocytic and endothelial cells. Blood 91, 577–584 (1998)

    CAS  Google Scholar 

  21. Li, P. et al. Mice deficient in IL-1β-converting enzyme are defective in production of mature IL-1β and resistant to endotoxic shock. Cell 80, 401–411 (1995)

    Article  CAS  Google Scholar 

  22. Friedlander, R. M. et al. Expression of a dominant negative mutant of interleukin-1β converting enzyme in transgenic mice prevents neuronal cell death induced by trophic factor withdrawal and ischemic brain injury. J. Exp. Med. 185, 933–940 (1997)

    Article  CAS  Google Scholar 

  23. Fernandes-Alnemri, T. et al. In vitro activation of CPP32 and Mch3 by Mch4, a novel human apoptotic cysteine protease containing two FADD-like domains. Proc. Natl Acad. Sci. USA 93, 7464–7469 (1996)

    Article  ADS  CAS  Google Scholar 

  24. Nunez, G., Benedict, M. A., Hu, Y. & Inohara, N. Caspases: the proteases of the apoptotic pathway. Oncogene 17, 3237–3245 (1998)

    Article  Google Scholar 

  25. Slee, E. A., Adrain, C. & Martin, S. J. Serial killers: ordering caspase activation events in apoptosis. Cell Death Differ. 6, 1067–1074 (1999)

    Article  CAS  Google Scholar 

  26. Aliprantis, A. O., Yang, R. B., Weiss, D. S., Godowski, P. & Zychlinsky, A. The apoptotic signaling pathway activated by Toll-like receptor-2. EMBO J. 19, 3325–3336 (2000)

    Article  CAS  Google Scholar 

  27. Jung, D. Y. et al. TLR4, but not TLR2, signals autoregulatory apoptosis of cultured microglia: a critical role of IFN-beta as a decision maker. J. Immunol. 174, 6467–6476 (2005)

    Article  CAS  Google Scholar 

  28. Kuno, R. et al. Autocrine activation of microglia by tumor necrosis factor-alpha. J. Neuroimmunol. 162, 89–96 (2005)

    Article  CAS  Google Scholar 

  29. Storz, P., Doppler, H. & Toker, A. Protein kinase Cdelta selectively regulates protein kinase D-dependent activation of NF-κB in oxidative stress signaling. Mol. Cell. Biol. 24, 2614–2626 (2004)

    Article  CAS  Google Scholar 

  30. Vancurova, I., Miskolci, V. & Davidson, D. NF-κB activation in tumor necrosis factor α-stimulated neutrophils is mediated by protein kinase Cδ. Correlation to nuclear IκBα. J. Biol. Chem. 276, 19746–19752 (2001)

    Article  CAS  Google Scholar 

  31. Reyland, M. E., Anderson, S. M., Matassa, A. A., Barzen, K. A. & Quissell, D. O. Protein kinase Cδ is essential for etoposide-induced apoptosis in salivary gland acinar cells. J. Biol. Chem. 274, 19115–19123 (1999)

    Article  CAS  Google Scholar 

  32. Czlonkowska, A., Kohutnicka, M., Kurkowska-Jastrzebska, I. & Czlonkowski, A. Microglial reaction in MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) induced Parkinson’s disease mice model. Neurodegeneration 5, 137–143 (1996)

    Article  CAS  Google Scholar 

  33. Aarli, J. A. Role of cytokines in neurological disorders. Curr. Med. Chem. 10, 1931–1937 (2003)

    Article  CAS  Google Scholar 

  34. Gonzalez-Scarano, F. & Baltuch, G. Microglia as mediators of inflammatory and degenerative diseases. Annu. Rev. Neurosci. 22, 219–240 (1999)

    Article  CAS  Google Scholar 

  35. Jordan, J., Segura, T., Brea, D., Galindo, M. F. & Castillo, J. Inflammation as therapeutic objective in stroke. Curr. Pharm. Des. 14, 3549–3564 (2008)

    Article  CAS  Google Scholar 

  36. Lenzlinger, P. M., Morganti-Kossmann, M. C., Laurer, H. L. & McIntosh, T. K. The duality of the inflammatory response to traumatic brain injury. Mol. Neurobiol. 24, 169–181 (2001)

    Article  CAS  Google Scholar 

  37. Allan, S. M. & Rothwell, N. J. Inflammation in central nervous system injury. Phil. Trans. R. Soc. Lond. B 358, 1669–1677 (2003)

    Article  CAS  Google Scholar 

  38. Karatas, H. et al. A nanomedicine transports a peptide caspase-3 inhibitor across the blood-brain barrier and provides neuroprotection. J. Neurosci. 29, 13761–13769 (2009)

    Article  CAS  Google Scholar 

  39. Bilsland, J. & Harper, S. Caspases and neuroprotection. Curr. Opin. Investig. Drugs 3, 1745–1752 (2002)

    CAS  PubMed  Google Scholar 

  40. Friedlander, R. M. Apoptosis and caspases in neurodegenerative diseases. N. Engl. J. Med. 348, 1365–1375 (2003)

    Article  CAS  Google Scholar 

  41. Le, D. A. et al. Caspase activation and neuroprotection in caspase-3-deficient mice after in vivo cerebral ischemia and in vitro oxygen glucose deprivation. Proc. Natl Acad. Sci. USA 99, 15188–15193 (2002)

    Article  ADS  CAS  Google Scholar 

  42. Joseph, B. et al. p57(Kip2) cooperates with Nurr1 in developing dopamine cells. Proc. Natl Acad. Sci. USA 100, 15619–15624 (2003)

    Article  ADS  CAS  Google Scholar 

  43. Bocchini, V. et al. An immortalized cell line expresses properties of activated microglial cells. J. Neurosci. Res. 31, 616–621 (1992)

    Article  CAS  Google Scholar 

  44. Giulian, D. & Baker, T. J. Characterization of ameboid microglia isolated from developing mammalian brain. J. Neurosci. 6, 2163–2178 (1986)

    Article  CAS  Google Scholar 

  45. Li, J. Y. et al. Lewy bodies in grafted neurons in subjects with Parkinson’s disease suggest host-to-graft disease propagation. Nature Med. 14, 501–503 (2008)

    Article  ADS  CAS  Google Scholar 

  46. Joseph, B. et al. Mitochondrial dysfunction is an essential step for killing of non-small cell lung carcinomas resistant to conventional treatment. Oncogene 21, 65–77 (2002)

    Article  CAS  Google Scholar 

  47. Rite, I., Machado, A., Cano, J. & Venero, J. L. Blood-brain barrier disruption induces in vivo degeneration of nigral dopaminergic neurons. J. Neurochem. 101, 1567–1582 (2007)

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We thank A. Gorman, O. Hermanson, M. Malewicz, S. Orrenius, T. Panaretakis and B. Zhivotovsky for discussion, and L. Hjortsberg, M. Reyland and S. Ceccatelli for providing us with reagents. M. Carballo, JL. Ribas, A. Fernández and B. Haraldsson provided qualified technical support. This work has been supported by grants from the Spanish Ministerio de Ciencia y Tecnología (SAF2006-04119 and 2009-13778), the Swedish Research Council, the Parkinson Foundation of Sweden, the Swedish Alzheimer Foundation and the Swedish Cancer Society. M.A.B., T.D. and P.B. are members of Neurofortis and Bagadilico, both of which are research environments sponsored by the Swedish Research Council.

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Authors

Contributions

M.A.B. performed all the experiments except as otherwise noted. qPCR was performed by A.G.-Q. and E.K. J.L.V. and J.C. collaborated in doing surgery and further dissecting the animal brains. M.A.B. and T.D. performed primary cell culture experiments and cytokine analysis. E.K. collaborated in performing the caspase activity assay. B.J. and E.K. collaborated in performing FACS. B.J. collaborated also in the confocal imaging analysis. E.E. did the neuropathology of the individuals with PD and AD and the controls. A.P. prepared tissue and participated in the morphological assessment of human brain specimens. N.H. and P.B. were involved in study design. M.A.B., J.L.V. and B.J. designed the study, analysed and interpreted the data. All authors discussed the results and commented on or edited the manuscript. The first draft of the paper was written by B.J. J.L.V. and B.J. share senior authorship of the paper. T.D and E.K. share second authorship.

Corresponding authors

Correspondence to Jose L. Venero or Bertrand Joseph.

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The authors declare no competing financial interests.

Supplementary information

Supplementary Information

This file contains Supplementary Figures 1-20 with legends, Supplementary Tables 1-3 and legends for Supplementary Movies 1-2. (PDF 20300 kb)

Supplementary Movie 1

This movie shows 3D confocal analysis of cleaved caspase-3 (in green) in lipopolysaccharide treated BV2 microglia cells. Nuclear and plasma membrane compartments were labeled with DAPI (Blue) and red fluorescent cholera toxin subunit B conjugates respectively. LPS-induced caspase-3 activation in BV2 microglia cells is restricted to plasma membrane compartment. (MOV 1592 kb)

Supplementary Movie 2

This movie shows 3D confocal analysis of cleaved caspase-3 (in green) in staurospaurine treated BV2 microglia cells. Nuclear and plasma membrane compartments were labeled with DAPI (Blue) and red fluorescent cholera toxin subunit B conjugates respectively. STS-induced caspase-3 activation in BV2 microglia cells accumulates in the nuclear compartment. (MOV 1349 kb)

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Burguillos, M., Deierborg, T., Kavanagh, E. et al. Caspase signalling controls microglia activation and neurotoxicity. Nature 472, 319–324 (2011). https://doi.org/10.1038/nature09788

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