The Regulating Mechanism of Chrysophanol on Protein Level of CaM-CaMKIV to Protect PC12 Cells Against Aβ25-35-Induced Damage

Drug Des Devel Ther. 2020 Jul 13:14:2715-2723. doi: 10.2147/DDDT.S245128. eCollection 2020.

Abstract

Objective: To investigate the neuroprotective effect of chrysophanol (CHR) on PC12 treated with Aβ25-35, and the involved mechanism.

Methods: After the establishment of an AD cell model induced by Aβ25-35, the cell survival rate was detected by MTT, cell apoptosis was assayed by Hoechst 33342 staining, mRNA expressions of calmodulin (CaM), calcium/calmodulin-dependent protein kinase kinase (CaMKK), calcium/calmodulin-dependent protein kinase IV (CaMKIV) and tau (MAPT; commonly known as tau) were determined by qRT-PCR, and protein levels of CaM, CaMKK, CaMKIV, phospho-CaMKIV (p-CaMKIV), tau and phospho-tau (p-tau) were detected by Western blot analysis.

Results: When pretreated with CHR before exposure to Aβ25-35, PC12 cells showed that increased cell viability and reduced apoptosis. The qRT-PCR results indicated that the deposition of Aβ25-35 triggers a decrease in levels of CaM, CaMKK, CaMKIV, and tau in PC12 cells. In addition, Western blot results also suggested that Aβ25-35 decreases the protein expression of CaM, CaMKK, CaMKIV, p-CaMKIV, and the ratio of p-tau to tau in PC12 cells. However, the above effects were significantly alleviated after the treatment of CHR.

Conclusion: CHR plays a neuroprotective role in AD though decreasing the protein level of CaM-CaMKK-CaMKIV and the expression of p-tau downstream.

Keywords: Alzheimer’s disease; CaM-CaMKK-CaMKIV; chrysophanol; p-tau.

MeSH terms

  • Amyloid beta-Peptides / antagonists & inhibitors*
  • Amyloid beta-Peptides / metabolism
  • Animals
  • Anthraquinones / metabolism
  • Anthraquinones / pharmacology*
  • Apoptosis / drug effects
  • Calcium-Calmodulin-Dependent Protein Kinase Type 4 / antagonists & inhibitors*
  • Calcium-Calmodulin-Dependent Protein Kinase Type 4 / genetics
  • Calcium-Calmodulin-Dependent Protein Kinase Type 4 / metabolism
  • Calmodulin / antagonists & inhibitors*
  • Calmodulin / genetics
  • Calmodulin / metabolism
  • Cell Survival / drug effects
  • Neuroprotective Agents / metabolism
  • Neuroprotective Agents / pharmacology*
  • PC12 Cells
  • Peptide Fragments / antagonists & inhibitors*
  • Peptide Fragments / metabolism
  • Rats
  • Tumor Cells, Cultured

Substances

  • Amyloid beta-Peptides
  • Anthraquinones
  • Calmodulin
  • Neuroprotective Agents
  • Peptide Fragments
  • amyloid beta-protein (25-35)
  • Calcium-Calmodulin-Dependent Protein Kinase Type 4
  • chrysophanic acid