Krabbe disease: involvement of connexin43 in the apoptotic effects of sphingolipid psychosine on mouse oligodendrocyte precursors

Apoptosis. 2016 Jan;21(1):25-35. doi: 10.1007/s10495-015-1183-4.

Abstract

Krabbe disease is a genetic demyelinating syndrome characterized by deficiency of the enzyme β-galactosylceramidase, lysosomal psychosine accumulation, and loss of myelin-forming cells. In this study, some apoptotic markers such as apoptotic index (AI), DNA fragmentation, caspase-3, PTEN, Bad, and PI3K were determined in oligodendrocyte precursors from wild type or twitcher mice untreated or treated with psychosine. Twitcher is a natural mouse model of Krabbe disease containing a premature stop codon (W339X) in the β-galactosylceramidase gene. Moreover, a possible involvement of connexin (Cx)43 in cell death of oligodendrocyte precursors induced by psychosine was investigated with the final aim to provide a contribution to the knowledge of the molecular mechanisms and pathophysiological events that occur in Krabbe disease. Connexins are a multigene family of structurally related trans-membrane proteins able to modulate essential cellular processes such as proliferation, differentiation and migration. Among these, Cx43 is the predominant isoform in many cell types, including neural progenitor cells. Our results showed an increase of AI, DNA fragmentation, caspase-3, PTEN, Bad, and Cx43 associated to a decrease of PI3K, pAKT and pBad. Taken together, these findings suggest an involvement of Cx43 in the psychosine-mediated apoptosis of primary oligodendrocyte progenitors from wild type or twitcher mice, used for the first time as cell models in comparison. It could open unexplored perspective also for other demyelinating diseases.

Keywords: Apoptosis; Cx43; GALC; Globoid cell leukodystrophy; Psychosine; Twitcher mouse.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Brain / drug effects*
  • Brain / enzymology
  • Brain / pathology
  • Caspase 3 / genetics
  • Caspase 3 / metabolism
  • Cell Differentiation / drug effects
  • Connexin 43 / genetics*
  • Connexin 43 / metabolism
  • DNA Fragmentation / drug effects
  • Disease Models, Animal
  • Galactosylceramidase / deficiency*
  • Galactosylceramidase / genetics
  • Gene Expression Regulation
  • Humans
  • Leukodystrophy, Globoid Cell / enzymology
  • Leukodystrophy, Globoid Cell / genetics*
  • Leukodystrophy, Globoid Cell / pathology
  • Lysosomes / drug effects
  • Lysosomes / enzymology
  • Lysosomes / pathology
  • Mice
  • Mice, Knockout
  • Oligodendroglia / drug effects*
  • Oligodendroglia / enzymology
  • Oligodendroglia / pathology
  • PTEN Phosphohydrolase / genetics
  • PTEN Phosphohydrolase / metabolism
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism
  • Psychosine / metabolism
  • Psychosine / pharmacology*
  • Signal Transduction
  • bcl-Associated Death Protein / genetics
  • bcl-Associated Death Protein / metabolism

Substances

  • Bad protein, mouse
  • Connexin 43
  • GJA1 protein, mouse
  • bcl-Associated Death Protein
  • Psychosine
  • Phosphatidylinositol 3-Kinases
  • PTEN Phosphohydrolase
  • Pten protein, mouse
  • Galactosylceramidase
  • Casp3 protein, mouse
  • Caspase 3