This report examines whether cognitive enrichment protects against hippocampal impairment induced by amyloid-beta oligomers. The authors found that prolonged exposure to an enriched environment facilitated activation of β-adrenergic receptors and downstream cAMP/PKA signaling in the hippocampus of wild-type mice. This pathway prevented LTP inhibition by soluble oligomers of amyloid-beta protein (Aβ). Exposure to novelty afforded greater protection than did aerobic exercise. Mice chronically fed a β-adrenergic agonist without environmental enrichment were also protected from hippocampal impairment by Aβ oligomers. The authors concluded that environmental enrichment enhances hippocampal synaptic plasticity by activating β-adrenoceptor signaling and mitigating synaptotoxicity of human Aβ oligomers. They propose that prolonged exposure to cognitive novelty and/or oral β-adrenergic agonists may lessen the effects of Aβ accumulation during aging.
Li S, Jin M, Zhang D, Yang T, Koeglsperger T, Fu H, Selkoe DJ: Environmental Novelty Activates β2-Adrenergic Signaling to Prevent the Impairment of Hippocampal LTP by Aβ Oligomers. Neuron 77(5): 929-941 (2013).