Elsevier

Neurobiology of Disease

Volume 8, Issue 2, April 2001, Pages 299-316
Neurobiology of Disease

Regular Article
Sublethal Concentrations of Prion Peptide PrP106–126 or the Amyloid Beta Peptide of Alzheimer's Disease Activates Expression of Proapoptotic Markers in Primary Cortical Neurons

https://doi.org/10.1006/nbdi.2001.0386Get rights and content

Abstract

Neurodegenerative disorders such as prion diseases and Alzheimer's disease (AD) are characterized by neuronal dysfunction and accumulation of amyloidogenic protein. In vitro studies have demonstrated that these amyloidogenic proteins can induce cellular oxidative stress and therefore may contribute to the neuronal dysfunction observed in these illnesses. Although the neurotoxic pathways are not fully elucidated, recent studies in AD have demonstrated up-regulation of caspases in neurons treated with amyloid beta (Aβ) peptide, suggesting involvement of apoptotic processes. To examine the role of proapoptotic pathways in prion diseases we treated primary mouse cortical neurons with the toxic prion protein peptide PrP106–126 and measured caspase activation and annexin V binding. We found that PrP106–126 induced a rapid and marked elevation in caspase 3, 6, and 8-like activity in neuronal cultures. Increased annexin V binding was observed predominantly on cortical cell neurites in peptide-treated cultures. Interestingly, these effects were induced by sublethal (5–50 μM) or lethal (100–200 μM) concentrations of PrP106–126. Sublethal concentrations of PrP106–126 maintained elevated caspase activation for at least 10 days with no loss of cell viability. Aβ1–40 also up-regulated caspase 3 activity and annexin V binding at both sublethal (5 μM) and lethal (25 μM) concentrations. There were no changes to proapoptotic marker expression in cultures treated with scrambled PrP106–126 (200 μM) or Aβ1–28 (25 μM) peptides. These studies demonstrate that amyloidogenic peptides can induce prolonged activation of proapoptotic marker expression in cultured neurons even at sublethal concentrations. These effects could contribute to chronic neuronal dysfunction and increase susceptibility to additional metabolic insults in neurodegenerative disorders. If so, targeting of therapeutic strategies against neuronal caspase activation early in the disease course could be beneficial in AD and prion diseases.

References (60)

  • L.F. Lue et al.

    Soluble amyloid beta peptide concentration as a predictor of synaptic change in Alzheimer's disease

    Am. J. Pathol.

    (1999)
  • M.P. Mattson et al.

    Evidence for synaptic apoptosis

    Exp. Neurol.

    (1998)
  • M.P. Mattson et al.

    Amyloid β-peptide induces apoptosis-related events in synapses and dendrites

    Brain Res.

    (1998)
  • D.W. Nicholson et al.

    Caspases: Killer proteases

    Trends Biochem. Sci.

    (1997)
  • G.S. Salvesen et al.

    Caspases: intracellular signalling by proteolysis

    Cell

    (1997)
  • S. Shimohama et al.

    Changes in caspase expression in Alzheimer's disease: Comparison with development and aging

    Biochem. Biophys. Res. Commun.

    (1999)
  • C. Stadelmann et al.

    Activation of caspase-3 in single neurons and autophagic granules of granulovacuolar degeneration in Alzheimer's disease

    Am. J. Pathol.

    (1999)
  • J. Wang et al.

    The levels of soluble versus insoluble brain A beta distinguish Alzheimer's disease from normal and pathologic aging

    Exp. Neurol.

    (1999)
  • A.R. White et al.

    Prion protein-deficient neurons reveal lower glutathione reductase activity and increased susceptibility to hydrogen peroxide toxicity

    Am. J. Pathol.

    (1999)
  • A. Williams et al.

    PrP deposition, microglial activation and neuronal apoptosis in murine scrapie

    Exp. Neurol.

    (1997)
  • T. Adayev et al.

    Externalization of phosphatidylserine may not be an early signal of apoptosis in neuronal cells but only the phosphatidylserine-displaying apoptotic cells are phagocytosed by microglia

    J. Neurochem.

    (1998)
  • S. Brandner et al.

    Normal host prion protein necessary for scrapie-induced neurotoxicity

    Nature

    (1996)
  • D.R. Brown et al.

    Mouse cortical cells lacking cellular PrP survive in culture with a neurotoxic PrP fragment

    Neuroreport

    (1994)
  • D.R. Brown et al.

    Role of microglia and host prion protein in neurotoxicity of a prion protein fragment

    Nature

    (1996)
  • D.R. Brown et al.

    PrP and beta-amyloid fragments activate different neurotoxic mechanisms in cultured mouse cells

    Eur. J. Neurosci.

    (1997)
  • D.R. Brown et al.

    Effects of copper on survival of prion protein knockout neurons and glia

    J. Neurochem.

    (1998)
  • A. Burkle et al.

    Poly(ADP-ribose) immunostaining to detect apoptosis induced by a neurotoxic fragment of prion protein

    Histochem. J.

    (1999)
  • C.K. Combs et al.

    Identification of microglial signal transduction pathways mediating a neurotoxic response to amyloidogenic fragments of β-amyloid and prion proteins

    J. Neurosci.

    (1999)
  • S.R. D'Mello et al.

    Caspase-3 is required for apoptosis-associated DNA fragmentation but not for cell death in neurons deprived of potassium

    J. Neurosci. Res.

    (2000)
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