Effects of Cannabidiol Interactions With Wnt/β-catenin Pathway and PPARγ on Oxidative Stress and Neuroinflammation in Alzheimer's Disease

Acta Biochim Biophys Sin (Shanghai). 2017 Oct 1;49(10):853-866. doi: 10.1093/abbs/gmx073.

Abstract

Alzheimer's disease (AD) is a neurodegenerative disease, in which the primary etiology remains unknown. AD presents amyloid beta (Aβ) protein aggregation and neurofibrillary plaque deposits. AD shows oxidative stress and chronic inflammation. In AD, canonical Wingless-Int (Wnt)/β-catenin pathway is downregulated, whereas peroxisome proliferator-activated receptor γ (PPARγ) is increased. Downregulation of Wnt/β-catenin, through activation of glycogen synthase kinase-3β (GSK-3β) by Aβ, and inactivation of phosphatidylinositol 3-kinase/Akt signaling involve oxidative stress in AD. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid from Cannabis sativa plant. In PC12 cells, Aβ-induced tau protein hyperphosphorylation is inhibited by CBD. This inhibition is associated with a downregulation of p-GSK-3β, an inhibitor of Wnt pathway. CBD may also increase Wnt/β-catenin by stimulation of PPARγ, inhibition of Aβ and ubiquitination of amyloid precursor protein. CBD attenuates oxidative stress and diminishes mitochondrial dysfunction and reactive oxygen species generation. CBD suppresses, through activation of PPARγ, pro-inflammatory signaling and may be a potential new candidate for AD therapy.

Keywords: Alzheimer's disease; GSK-3β; PI3K/Akt pathway; PPARγ; Wnt/β-catenin pathway; cannabidiol; neuroinflammation; oxidative stress.

MeSH terms

  • Alzheimer Disease / metabolism*
  • Alzheimer Disease / pathology
  • Amyloid beta-Peptides / metabolism
  • Animals
  • Cannabidiol / pharmacology*
  • Glycogen Synthase Kinase 3 beta / metabolism
  • Inflammation / metabolism*
  • Inflammation / pathology
  • Models, Biological
  • Neurofibrillary Tangles / metabolism
  • Oxidative Stress / drug effects*
  • PC12 Cells
  • PPAR gamma / metabolism*
  • Phosphorylation
  • Rats
  • Wnt Signaling Pathway / drug effects*
  • tau Proteins / metabolism

Substances

  • Amyloid beta-Peptides
  • PPAR gamma
  • tau Proteins
  • Cannabidiol
  • Glycogen Synthase Kinase 3 beta