Evaluation of the Anti-Alzheimer Activity of Lycium barbarum Polysaccharide in Aβ(1-42)-Induced Neurotoxicity in Rat Model.

As a common neurodegenerative disorder, Alzheimer's disease (AD) manifests as progressive memory loss, cognitive deficits, and dementia in older adults. As the basis of the traditional Chinese medicinal herb Goji berries, Lycium barbarum polysaccharide (LBP) has been proven to exhibit multiple pharmacological activities, including antioxidant, neuroprotective, and anti-inflammatory effects. Evidence supports that LBP can enhance cognitive function and holds promise in counteracting AD. In order to determine the neuroprotective effects of LBP, this study was conducted on an AD rat model induced by intracerebroventricular injection of Aβ(1-42) peptides. From 24 h after induction until the end of the behavioral experiment, rats were orally administered LBP (150 and 300 mg/kg) once a day. Neurobehavioral parameters were evaluated starting 1 week after administration. After behavioral tests, rats were euthanized, and the whole brain and cortex were isolated to detect the variations in histopathology and biochemical parameters. LBP significantly reversed cognitive impairments, assessed through the Y-maze, Passive Avoidance Test (PAT), and Morris water maze (MWM) test, respectively. Furthermore, LBP not only attenuated NFκB, TNF-α, IL-1β, IL-6, AChE, and oxidative/nitrosative stress levels but also increased IL-4, IL-10, and ACh levels and ChAT activity in the cortex. HE staining also exhibited the neuroprotection of LBP. Our study findings imply that LBP may improve cognitive function through multiple mechanisms and is a potential anti-AD compound.