Tauroursodeoxycholic acid modulates p53-mediated apoptosis in Alzheimer's disease mutant neuroblastoma cells

J Neurochem. 2006 Sep;98(5):1610-8. doi: 10.1111/j.1471-4159.2006.04007.x.

Abstract

Early onset familial Alzheimer's disease (FAD) is linked to autosomal dominant mutations in the amyloid precursor protein (APP) and presenilin 1 and 2 (PS1 and PS2) genes. These are critical mediators of total amyloid beta-peptide (Abeta) production, inducing cell death through uncertain mechanisms. Tauroursodeoxycholic acid (TUDCA) modulates exogenous Abeta-induced apoptosis by interfering with E2F-1/p53/Bax. Here, we used mouse neuroblastoma cells that express either wild-type APP, APP with the Swedish mutation (APPswe), or double-mutated human APP and PS1 (APPswe/DeltaE9), all exhibiting increased Abeta production and aggregation. Cell viability was decreased in APPswe and APPswe/DeltaE9 but was partially reversed by z-VAD.fmk. Nuclear fragmentation and caspase 2, 6 and 8 activation were also readily detected. TUDCA reduced nuclear fragmentation as well as caspase 2 and 6, but not caspase 8 activities. p53 activity, and Bcl-2 and Bax changes, were also modulated by TUDCA. Overexpression of p53, but not mutant p53, in wild-type and mutant neuroblastoma cells was sufficient to induce apoptosis, which, in turn, was reduced by TUDCA. In addition, inhibition of the phosphatidylinositide 3'-OH kinase pathway reduced TUDCA protection against p53-induced apoptosis. In conclusion, FAD mutations are associated with the activation of classical apoptotic pathways. TUDCA reduces p53-induced apoptosis and modulates expression of Bcl-2 family.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease / genetics*
  • Amino Acid Chloromethyl Ketones / pharmacology
  • Amyloid beta-Protein Precursor / genetics
  • Animals
  • Antiviral Agents / pharmacology*
  • Apoptosis / drug effects*
  • Apoptosis / physiology
  • Blotting, Western
  • Caspases / metabolism
  • Cell Line, Tumor
  • Cysteine Proteinase Inhibitors / pharmacology
  • Enzyme Activation / drug effects
  • Humans
  • In Situ Nick-End Labeling / methods
  • Membrane Proteins / genetics
  • Mice
  • Mutation*
  • Neuroblastoma
  • Presenilin-1
  • Presenilin-2
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Taurochenodeoxycholic Acid / pharmacology*
  • Transfection / methods
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*
  • bcl-2-Associated X Protein / metabolism

Substances

  • Amino Acid Chloromethyl Ketones
  • Amyloid beta-Protein Precursor
  • Antiviral Agents
  • Cysteine Proteinase Inhibitors
  • Membrane Proteins
  • PSEN1 protein, human
  • PSEN2 protein, human
  • Presenilin-1
  • Presenilin-2
  • Proto-Oncogene Proteins c-bcl-2
  • Tumor Suppressor Protein p53
  • bcl-2-Associated X Protein
  • benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone
  • Taurochenodeoxycholic Acid
  • ursodoxicoltaurine
  • Caspases