β-asarone improves learning and memory and reduces Acetyl Cholinesterase and Beta-amyloid 42 levels in APP/PS1 transgenic mice by regulating Beclin-1-dependent autophagy

Brain Res. 2016 Dec 1:1652:188-194. doi: 10.1016/j.brainres.2016.10.008. Epub 2016 Oct 11.

Abstract

Alzheimer's disease (AD) is the most common neurodegenerative disorder in the elderly, and studies have suggested that β-asarone has pharmacological effects on beta-amyloid (Aβ) injected in the rat hippocampus. However, the effect of β-asarone on autophagy in the APP/PS1 transgenic mouse is unreported. APP/PS1 transgenic mice were randomly divided into six groups (n=10/group): an untreated group, an Aricept-treated group, a 3-MA-treated group, a rapamycin-treated group, an LY294002-treated group, a β-asarone-treated group. The control group consisted of wild-type C57BL/6 mice. All treatments were administered to the mice for 30 days. Spatial learning and memory were assessed by water maze, passive avoidance, and step-down tests. AChE and Aβ42 levels in the hippocampus were determined by ELISA. p-Akt, p-mTOR, and LC3B expression were detected by flow cytometry. The expression of p-Akt, p-mTOR, Beclin-1, and p62 proteins was assessed by western blot. Changes in autophagy were viewed using a transmission electron microscope. APP and Beclin-1 mRNA levels were measured by Real-Time PCR. The learning and memory of APP/PS1 transgenic mice were improved significantly after β-asarone treatment compared with the untreated group. In addition, β-asarone treatment reduced AChE and Aβ42 levels, increased p-mTOR and p62 expression, decreased p-Akt, Beclin-1, and LC3B expression, decreased the number of autophagosomes and reduced APP mRNA and Beclin-1 mRNA levels compared with the untreated group. That is, β-asarone treatment can improve the learning and memory abilities of APP/PS1 transgenic mouse by inhibiting Beclin-1-dependent autophagy via the PI3K/Akt/mTOR pathway.

Keywords: APP/PS1 transgenic mice; Alzheimer’s disease; Autophagy; PI3K/Akt/mTOR pathway; β-asarone.

MeSH terms

  • Acetylcholinesterase / metabolism*
  • Administration, Oral
  • Allylbenzene Derivatives
  • Alzheimer Disease / drug therapy
  • Alzheimer Disease / metabolism
  • Alzheimer Disease / pathology
  • Amyloid beta-Peptides / metabolism
  • Amyloid beta-Protein Precursor / genetics
  • Amyloid beta-Protein Precursor / metabolism
  • Animals
  • Anisoles / pharmacology*
  • Autophagy / drug effects*
  • Autophagy / physiology
  • Beclin-1 / metabolism
  • Disease Models, Animal
  • Female
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Humans
  • Learning / drug effects*
  • Learning / physiology
  • Male
  • Memory / drug effects*
  • Memory / physiology
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Nootropic Agents / pharmacology*
  • Peptide Fragments / metabolism
  • Presenilin-1 / genetics
  • Presenilin-1 / metabolism
  • Random Allocation
  • Signal Transduction / drug effects

Substances

  • APP protein, human
  • Allylbenzene Derivatives
  • Amyloid beta-Peptides
  • Amyloid beta-Protein Precursor
  • Anisoles
  • Beclin-1
  • Becn1 protein, mouse
  • Nootropic Agents
  • PSEN1 protein, human
  • Peptide Fragments
  • Presenilin-1
  • amyloid beta-protein (1-42)
  • asarone
  • Acetylcholinesterase