RESUMO
Linguizhugan decoction (LGZG), a notable prescription in Traditional Chinese Medicine, is a classical formula for the treatment of Alzheimer's disease (AD), inflammatory injury and fluid retention. The present study aimed to investigate the neuroprotective effect of LGZG on an amyloid ß (Aß)induced AD rat model. SpragueDawley rats were administered with Aß142 to induce AD and inflammatory responses, and subsequently with LGZG (4.8, 2.4 or 1.2 g/kg), donepezil (2 mg/kg) or distilled water for 30 consecutive days. Learning and memory behaviors were evaluated via Morris water maze test. The neuronal impairment of AD rats was observed via hematoxylineosin staining. The levels of proinflammatory cytokines, and Aß in the brain tissue were detected with ELISA kits. Protein expression levels of mitogenactivated protein kinase and nuclear factorκB signalling were measured by western blot analysis. The expression of lipoprotein receptorrelated protein1 (LRP1) and receptor for advanced glycation endproducts (RAGE) in the brain were detected by western blot analysis, reverse transcriptionquantitative polymerase chain reaction and immunohistochemistry analysis. LGZG was demonstrated to significantly improve learning and memory ability, and ameliorate neuroinflammation in AD rats. LGZG increased the levels of LRP1 and decreased the levels of RAGE. Furthermore, the present results demonstrated that LGZG treatment significantly inhibited MAPK and NFκB signalling, and reduced the production of proinflammatory cytokines and Aß accumulation in AD rats. LGZG exhibited a potential protective effect on Aß142induced AD by regulating Aß transportation, and inhibiting RAGE/MAPK and NFκB signalling. These results suggest that LGZG may be considered for the treatment of AD.