Brazilian green propolis (propolis) is a chemically complex resinous substance that is a potentially viable therapeutic agent for Alzheimer’s disease. Herein, propolis induced a transient increase in intracellular Ca concentration ([Ca]) in Neuro-2A cells; moreover, propolis-induced [Ca] elevations were suppressed prior to 24-h pretreatment with amyloid-β. To reveal the effect of [Ca] elevation on impaired cognition, we performed memory-related behavioral tasks in APP-KI mice relative to WT mice at 4 and 12 months of age. Propolis, at 300–1000 mg/kg/d for 8 wk, significantly ameliorated cognitive deficits in APP-KI mice at 4 months, but not at 12 months of age. Consistent with behavioral observations, injured hippocampal long-term potentiation was markedly ameliorated in APP-KI mice at 4 months of age following repeated propolis administration. In addition, repeated administration of propolis significantly activated intracellular calcium signaling pathway in the CA1 region of APP-KI mice. These results suggest a preventive effect of propolis on cognitive decline through the activation of intracellular calcium signaling pathways in CA1 region of AD mice model.

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蜂胶对阿尔茨海默病模型小鼠认知能力下降的预防作用

巴西绿蜂胶（蜂胶）是一种化学成分复杂的树脂物质，是治疗阿尔茨海默病的潜在可行药物。在此，蜂胶诱导 Neuro-2A 细胞中细胞内 Ca 浓度 ([Ca]) 短暂增加；此外，在用淀粉样蛋白-β 预处理 24 小时之前，蜂胶引起的 [Ca] 升高受到抑制。为了揭示 [Ca] 升高对认知受损的影响，我们在 4 个月和 12 个月大的 APP-KI 小鼠中相对于 WT 小鼠进行了与记忆相关的行为任务。蜂胶以 300–1000 mg/kg/d 的剂量持续 8 周，可以显着改善 APP-KI 小鼠 4 个月大时的认知缺陷，但不能改善 12 个月大时的认知缺陷。与行为观察结果一致，重复给予蜂胶后 4 个月大的 APP-KI 小鼠受损的海马长时程增强功能显着改善。此外，重复给予蜂胶可显着激活 APP-KI 小鼠 CA1 区的细胞内钙信号通路。这些结果表明，蜂胶通过激活 AD 小鼠模型 CA1 区的细胞内钙信号通路，对认知能力下降具有预防作用。