ABSTRACT
Objective:To investigate the neuroprotective effect of Danggui Shaoyaosan （DSS） in a rat model of amyloid-<italic>β</italic>-peptide<sub>1-42</sub> （A<italic>β</italic><sub>1-42</sub>）-induced Alzheimer's disease （AD） as well as its regulatory effect on NOD-like receptor protein 3 （NLRP3）/cysteinyl aspartate-specific protease-1 （Caspase-1） signaling pathway. Method:The AD animal model was established via intracerebral injection of A<italic>β</italic><sub>1-42</sub> and treated with different concentrations of DSS after the division of rats into the sham operation group， model group， as well as the high-， medium-， and low-dose DSS groups. Morris water maze test was conducted to determine the learning and memory abilities of rats. The morphology and function of neurons were detected by hematoxylin-eosin （HE） staining and Golgi staining， followed by immunofluorescence co-localization of NLRP3 inflammasome activation. The mRNA expression levels of interleukin （IL）-1<italic>β</italic> and IL-18 were measured by Real-time polymerase chain reaction （Real-time PCR）， and the protein expression levels of NLRP3， Caspase-1， and IL-1<italic>β </italic>were assayed by Western blot. Result:Compared with the sham operation group， the model group exhibited significantly decreased learning and memory abilities （<italic>P</italic><0.01）， impaired neuronal morphology and function， up-regulated IL-1<italic>β</italic> and IL-18 mRNA expression， enhanced NLRP3 inflammasome activation， and elevated NLRP3， Caspase-1， and IL-1<italic>β</italic> protein expression （<italic>P</italic><0.01）. Compared with the model group， DSS at both medium and high doses remarkably improved the learning and memory abilities of AD rats （<italic>P</italic><0.05， <italic>P</italic><0.01）， restored neuronal morphology and function， down-regulated the mRNA expression levels of inflammatory factors IL-1<italic>β</italic> and IL-18， reduced the activation of NLRP3 inflammasomes， and lowered the protein expression levels of NLRP3， Caspase-1， and IL-1<italic>β</italic> （<italic>P</italic><0.01）. Conclusion:DSS inhibits inflammasome activation and neuroinflammatory response possibly by regulating the NLRP3/Caspase-1 signaling pathway， thus exerting the neuroprotective effect.