[Involvement of Wnt/beta-catenin signaling in tripchlorolide protecting against oligomeric beta-amyloid-(1-42)-induced neuronal apoptosis]

Yao Xue Xue Bao. 2010 Jul;45(7):853-9.
[Article in Chinese]

Abstract

This study is to explore whether the Wnt/beta-catenin signaling pathway is involved in the process of tripchlorolide (T4) protecting against oligomeric Abeta(1-42)-induced neuronal apoptosis. Primary cultured cortical neurons were used for the experiments on day 6 or 7. The oligomeric Abeta(1-42) (5 micromol x L(-1) for 24 h) was applied to induce neuronal apoptosis. Prior to treatment with Abeta(1-42) for 24 h, the cultured neurons were pre-incubated with T4 (2.5, 10, and 40 nmol x L(-1)), Wnt3a (Wnt signaling agonists) and Dkk1 (inhibitors) for indicated time. Then the cell viability, neuronal apoptosis, and protein levels of Wnt, glycogen synthase kinase 3beta (GSK3beta), beta-catenin and phospho-beta-catenin were measured by MTT assay, TUNEL staining and Western blotting, respectively. The result demonstrated that oligomeric Abeta(1-42) induced apoptotic neuronal cell death in a time- and dose-dependent manner. Pretreatment with T4 significantly increased the neuronal cell survival and attenuated neuronal apoptosis. Moreover, oligomeric Abeta(1-42)-induced phosphorylation of beta-catenin and GSK3beta was markedly inhibited by T4. Additionally, T4 stabilized cytoplasmic beta-catenin. These results indicate that tripchlorolide protects against the neurotoxicity of Abeta by regulating Wnt/beta-catenin signaling pathway. This may provide insight into the clinical application of tripchlorolide to Alzheimer's disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amyloid beta-Peptides / antagonists & inhibitors
  • Amyloid beta-Peptides / toxicity*
  • Animals
  • Apoptosis / drug effects*
  • Cell Survival / drug effects
  • Cells, Cultured
  • Cerebral Cortex / cytology
  • Diterpenes / isolation & purification
  • Diterpenes / pharmacology*
  • Female
  • Fetus
  • Glycogen Synthase Kinase 3 / metabolism
  • Glycogen Synthase Kinase 3 beta
  • Neurons / cytology
  • Neurons / drug effects
  • Neuroprotective Agents / isolation & purification
  • Neuroprotective Agents / pharmacology
  • Peptide Fragments / antagonists & inhibitors
  • Peptide Fragments / toxicity*
  • Phenanthrenes / isolation & purification
  • Phenanthrenes / pharmacology*
  • Phosphorylation
  • Plants, Medicinal / chemistry
  • Pregnancy
  • Rats
  • Rats, Sprague-Dawley
  • Signal Transduction*
  • Tripterygium / chemistry
  • Wnt Proteins / metabolism*
  • beta Catenin / metabolism*

Substances

  • Amyloid beta-Peptides
  • Ctnnb1 protein, rat
  • Diterpenes
  • Neuroprotective Agents
  • Peptide Fragments
  • Phenanthrenes
  • Wnt Proteins
  • amyloid beta-protein (1-42)
  • beta Catenin
  • tripchlorolide
  • Glycogen Synthase Kinase 3 beta
  • Gsk3b protein, rat
  • Glycogen Synthase Kinase 3