Human placenta extract ameliorates memory dysfunction and dendritic atrophy in a 5XFAD mouse model of Alzheimer's disease

Abstract

ABSTRACTAimIn this study, we investigated the effects of a human placenta‐derived drug, Laennec (Japan Bio Products), on memory improvement and neuritic regeneration in Alzheimer's disease model mice, to evaluate the potential of Laennec as a new candidate for anti‐Alzheimer's disease (AD) therapy.MethodsThe anti‐AD effects of Laennec were evaluated using amyloid β (Aβ)‐treated cortical neurons and the 5XFAD mouse model of AD.ResultsLaennec significantly improved the dendritic density in normal cortical neurons but not the axon density. Exposure to the peptide fragment Aβ(25–35) for 3 days resulted in significant atrophy in the axons and dendrites of cortical neurons (ddY mice, E14). Laennec significantly improved the density and dendritic length of the Aβ‐treated cortical neurons but did not affect axon atrophy. Synaptic loss induced by Aβ(25–35) was also completely reversed by Laennec treatment. The Laennec‐treated 5XFAD mice (for 15 days, i.p. or p.o.; 5–7 months old, female) showed significant improvement in object recognition memory, but had no reduction in amyloid plaques in the perirhinal cortex, although the reduced dendritic density in the amyloid plaque‐associated sites was significantly increased by Laennec treatment. Furthermore, the components of Laennec were separated based on their molecular weights using ultrafiltration. The Laennec fraction >2 kDa contained the active compounds for dendrite extension.ConclusionLaennec improved object recognition memory and dendritic growth in a model of AD.