Protective Effects of Onjisaponin B in a Mouse Model of Alzheimer’s Disease via Enhancement of Hippocampal Neuroplasticity

Alzheimer’s disease mainly affects elderly population leading to impairment in cogitation. A lack of clear understanding of the mechanism of Alzheimer’s disease has led to a lack of definite therapeutic option. Herein we have explored the effect of Onjisaponin B derived from the traditional Chinese herbal medicinal plant Radix Polygalae in an animal model of Alzheimer’s disease. Onjisaponin B significantly reduced the severity of experimental Alzheimer’s disease in mice measured by learning abilities, spatial learning, memory, and recognition of novel objects via modulation of hippocampal neuroplasticity. Neuroplasticity was further confirmed by silver staining and expression of major proteins in the hippocampal synapse. Furthermore, Onjisaponin B remarkably altered the morphology of neuron dendrites in the CA1 region by increasing the numbers of apical and basal dendrites of neurons, and the length of neurons. In conclusion, Onjisaponin B might modulate neuroplasticity to attenuate Alzheimer’s disease.