Nasal administration of cholera toxin B subunit–nerve growth factor improves the space learning and memory abilities in β-amyloid protein25-35-induced amnesic mice

Nerve growth factor (NGF) is a potential drug for Alzheimer's disease treatment, but delivering NGF to the brain is difficult. To increase the content of NGF in brain, we prepared cholera toxin B subunit (CB) –NGF by the improved sodium metaperiodate method and compared its pharmacodynamics with NGF. In vitro, CB-NGF, as well as NGF, could promote neurite outgrowth and increase choline acetyltransferase activities. But the time window of TrkA phosphorylation induced by CB-NGF and NGF was different. In vivo, nasal administration of CB-NGF could increase the stay time and partially improve abilities of space learning and memory in amnesic mice, and protected the cholinergic neurons in basal forebrain against Aβ25-35. CB-NGF treatment has better curative effects than NGF in Alzheimer's disease model mice.