Preventive Effects of Psoraleae Semen Extracts on Cognitive Dysfunction in Alzheimer's Disease Model App^NL-P-F Mice

Oxidative stress and neuroinflammation accompanied by microglial activation are increased in Alzheimer's disease (AD) and contribute to the pathogenesis of AD. Nuclear factor erythroid-derived 2-related factor 2 (Nrf2) is a master transcription factor that acts as an endogenous defense mechanism against oxidative stress and inflammation and is a potential target for preventing AD. Psoraleae Semen (PS) reportedly has antioxidant and anti-inflammatory effects. This study aimed to examine the effects of PS extract (PSE) on Nrf2 activation and prevention of cognitive dysfunction in App^NL-P-F AD model mice. The effects of PSE on antioxidant response element (ARE) activity and cytoprotection in PC12 cells and on microglial activation in BV-2 cells were evaluated. PSE showed high ARE activity and prevented 6-hydroxydopamine-induced cytotoxicity in PC12 cells. Moreover, PSE suppressed lipopolysaccharide-induced nitric oxide production in BV-2 cells. Oral administration of PSE prevented cognitive dysfunction in App^NL-P-F mice without affecting motor function. Our results support that PSE can contribute to the development of new preventive and therapeutic agents for AD focusing on Nrf2 activation.