Alzheimer's disease, one of the most common types of age-related dementia, is characterized by memory deterioration and behavior disorder. The aboveground part of Polygala tenuifolia is a traditional Chinese medicine used for the treatment of amnesia. This study was conducted to investigate the ameliorating effect of the aerial part of P. tenuifolia on d-galactose/NaNO2-induced learning and memory impairment in mice. d-galactose (120 mg/kg) and NaNO2 (90 mg/kg) were injected intraperitoneally for 60 days to induce learning and memory impairment in mice. The aerial part of P. tenuifolia (25, 50, and 100 mg/kg) and piracetam (200 mg/kg) were simultaneously administered orally on days 15 - 60. Results of this study showed that aerial part of P. tenuifolia significantly decreased the latency time and increased the number of platform crossings in the Morris water maze compared with the Model group. Moreover, the aerial part of P. tenuifolia significantly increased the latency time and decreased the error frequency in the step-down and step-through tests compared with the Model group. Meanwhile, the aerial part of P. tenuifolia was able to regulate the cholinergic system by increasing the levels of ACh and ChAT and decreasing the level of AChe. The aerial part of P. tenuifolia also significantly attenuated the levels of interleukin-1 beta and malonaldehyde and enhanced the interleukin-10 and glutathione levels and superoxide dismutase activity. Furthermore, treatment with aerial part of P. tenuifolia increased the protein and mRNA expression of brain-derived neurotrophic factor and tropomyosin receptor kinase B in the hippocampus. These results suggest that the aerial part of P. tenuifolia can ameliorate learning and memory impairments by modulating cholinergic activity, inhibiting neuroinflammation and oxidative stress, and regulating the brain-derived neurotrophic factor and tropomyosin receptor kinase B signaling pathway.

中文翻译：

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远志的地上部分提取物减轻 d-半乳糖/NaNO2 诱导的小鼠学习和记忆障碍

阿尔茨海默病是与年龄相关的痴呆症中最常见的类型之一，其特征是记忆力衰退和行为障碍。远志地上部分是治疗健忘症的中药。本研究旨在研究细叶松的地上部分对 d-半乳糖/NaNO2 诱导的小鼠学习记忆障碍的改善作用。d-半乳糖 (120 mg/kg) 和 NaNO2 (90 mg/kg) 腹腔注射 60 天，以诱导小鼠学习和记忆障碍。P. tenuifolia 地上部分（25、50 和 100 毫克/千克）和吡拉西坦（200 毫克/千克）在第 15-60 天同时口服给药。这项研究的结果表明，P. 与模型组相比，tenuifolia 显着减少了莫里斯水迷宫中的潜伏时间并增加了平台交叉次数。此外，与模型组相比，细叶松的地上部分在降压和跨步测试中显着增加了潜伏时间并降低了错误频率。同时，细叶松的地上部分能够通过增加 ACh 和 ChAT 的水平并降低 ACh 的水平来调节胆碱能系统。P. tenuifolia 的地上部分还显着降低了白细胞介素 1 β 和丙二醛的水平，并增强了白细胞介素 10 和谷胱甘肽水平以及超氧化物歧化酶活性。此外，用P的地上部分处理。细叶增加了海马中脑源性神经营养因子和原肌球蛋白受体激酶 B 的蛋白质和 mRNA 表达。这些结果表明，细叶松的地上部分可以通过调节胆碱能活性、抑制神经炎症和氧化应激、调节脑源性神经营养因子和原肌球蛋白受体激酶 B 信号通路来改善学习和记忆障碍。