Activation of α7 Nicotinic Acetylcholine Receptor by its Selective Agonist Improved Learning and Memory of Amyloid Precursor Protein/Presenilin 1 (APP/PS1) Mice via the Nrf2/HO-1 Pathway.

BACKGROUND To reveal the mechanism underlying the effect of alpha7 nicotinic acetylcholine receptor (nAChR) on neurodegeneration in Alzheimer disease (AD), the influence of the receptor on recognition in APP/PS1 mice was evaluated by using its selective agonist (PNU-282987). MATERIAL AND METHODS APP/PS1 and wild-type (WT) mice were treated with PNU or saline, respectively, for 7 days at the ages of 6 and 10 months. RESULTS Morris water maze analysis showed that both at 6 and 10 months of age, PNU treatment enhanced the learning and memory of APP/PS1 mice. However, PNU treatment did not alter the number of senile plaques. Furthermore, a higher protein expression of Nrf2/HO-1, ADAM10, SYP, and SNAP-25, and a lower level of oxidative stress, were observed in the hippocampus of APP/PS1 mice treated with PNU compared with the control group. CONCLUSIONS The results indicated that the activation of alpha7 nAChR by PNU improved the learning and memory of mice carrying the APP/PS1 mutation, regulated the levels of enzymes that mediate APP metabolization to reduce ß-amyloid peptide damage, and decreased the level of oxidative stress and maintained synaptic plasticity, in which the mechanism might be enhancement of the Nrf2/HO-1 pathway.