Curcumin Decreases Hyperphosphorylation of Tau by Down-Regulating Caveolin-1/GSK-3β in N2a/APP695swe Cells and APP/PS1 Double Transgenic Alzheimer's Disease Mice

Am J Chin Med. 2017;45(8):1667-1682. doi: 10.1142/S0192415X17500902. Epub 2017 Nov 13.

Abstract

Caveolin-1, the marker protein of membranal caveolae, is not only involved in cholesterol regulation, but also participates in the cleavage of amyloid [Formula: see text]-protein precursor (APP) and the generation of [Formula: see text]-amyloid peptide. It has been reported to be tightly related with Tau. In our previous studies, curcumin has been confirmed to play a neuroprotective role in Alzheimer's disease (AD), but its effects on Caveolin-1, Tau and their correlation, and the mechanism is still unknown. As such, in the present study, N2a/WT cells, N2a/APP695swe cell and six-month-old APP/PS1 double transgenic mice were enrolled. After curcumin treatment, the expression of Caveolin-1, Tau and their relationship was detected, and the potential mechanisms were explored. The results showed that in the N2a/APP695swe cells, curcumin not only decreased the number of caveolae, but also made their membrane to be thinner; and curcumin could decreased the expression of phosphorylated Tau (P-Tau(ser404)/Tau) and Caveolin-1 ([Formula: see text]), but the expression of phosphorylated GSK-3[Formula: see text] (P-GSK-3[Formula: see text]/GSK-3[Formula: see text] was increased ([Formula: see text]). In APP/PS1 transgenic mice, the same results were observed. Taken together, our data suggest that curcumin may play an important role in AD via reducing Caveolin-1, inactivating GSK-3[Formula: see text] and inhibiting the abnormal excessive phosphorylation of Tau, which will provide a new theory for AD treatment with curcumin.

Keywords: Alzheimer’s Disease; Caveolin-1; Curcumin; GSK-3; Tau.

MeSH terms

  • Alzheimer Disease / drug therapy
  • Alzheimer Disease / genetics*
  • Alzheimer Disease / metabolism*
  • Amyloid beta-Peptides / metabolism
  • Amyloid beta-Protein Precursor / genetics
  • Amyloid beta-Protein Precursor / metabolism
  • Animals
  • Brain / metabolism
  • Caveolae / drug effects
  • Caveolae / pathology
  • Caveolin 1 / genetics
  • Caveolin 1 / metabolism
  • Caveolin 1 / physiology*
  • Cells, Cultured
  • Curcumin / pharmacology*
  • Curcumin / therapeutic use
  • Down-Regulation / drug effects*
  • Gene Expression / drug effects
  • Glycogen Synthase Kinase 3 / genetics*
  • Glycogen Synthase Kinase 3 / metabolism*
  • Mice, Transgenic
  • Molecular Targeted Therapy
  • Phosphorylation / drug effects
  • Phytotherapy
  • tau Proteins / genetics
  • tau Proteins / metabolism*

Substances

  • Amyloid beta-Peptides
  • Amyloid beta-Protein Precursor
  • Caveolin 1
  • tau Proteins
  • Glycogen Synthase Kinase 3
  • Curcumin