One of the pathological hallmarks of Alzheimer's disease (AD) is the abnormal aggregation of amyloid beta (Aβ) peptides. Uncaria rhynchophylla (UR), one of the Uncaria species, has long been used to treat neurodegenerative disease. In particular, it has been reported that UR inhibits aggregation of Aβ in vitro. However, little is known about the histological effects of UR treatment on Aβ pathology in AD animal models. In the present study, we investigated the effect of UR on Aβ aggregation, Aβ-mediated pathologies and adult hippocampal neurogenesis in the brain of 5XFAD mice. First, using the thioflavin T assay and amyloid staining, we demonstrated that UR treatment effectively inhibited Aβ aggregation and accumulation in the cortex and subiculum. Second, immunofluorescence staining showed that administration of UR attenuated gliosis and neurodegeneration in the subiculum and cortex. Third, UR treatment ameliorated impaired adult hippocampal neurogenesis. The present results indicate that UR significantly alleviates Aβ deposition and Aβ-mediated neuropathology in the brain in 5XFAD mice, suggesting the potency of UR as a preventive and therapeutic agent for AD.

阿尔茨海默氏病（AD）的病理特征之一是淀粉样β（Aβ）肽的异常聚集。钩藤（Uncaria rhynchophylla）（UR）是钩藤（Uncaria）物种之一，长期以来一直用于治疗神经退行性疾病。特别地，已经报道了UR在体外抑制Aβ的聚集。但是，关于UR治疗对AD动物模型中Aβ病理的组织学影响知之甚少。在本研究中，我们研究了UR对5XFAD小鼠大脑中Aβ聚集，Aβ介导的病理学和成年海马神经发生的影响。首先，使用硫代黄素T分析法和淀粉样蛋白染色，我们证明了UR治疗有效抑制了Aβ在皮质和下丘脑的聚集和积累。其次，免疫荧光染色显示施用UR可减轻下丘脑和皮层的神经胶质增生和神经变性。第三，UR治疗改善了成年海马神经发生受损。目前的结果表明，UR可以显着缓解5XFAD小鼠大脑中Aβ沉积和Aβ介导的神经病理学，