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. 
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.