Wang Rui-Fang, Song Jun-Ying, Zhao Huan-Dong, Jia Ya-Quan, Yuan Yong, Ding Rui, Wang Meng-Fei, Zhang Zhen-Qiang
Academy of Chinese Medical Science, Henan University of Chinese Medicine Zhengzhou 450046, China the First Affiliated Hospital of Henan University of Chinese Medicine Zhengzhou 450046, China.
Academy of Chinese Medical Science, Henan University of Chinese Medicine Zhengzhou 450046, China.
Zhongguo Zhong Yao Za Zhi. 2024 Apr;49(7):1924-1931. doi: 10.19540/j.cnki.cjcmm.20240115.702.
The Chinese medical mechanism of Huanglian Jieduo Decoction on treating Alzheimer's disease(AD) characterized by "toxin damaging brain collateral" is still unclear. This study aims to explore the mechanism of Huanglian Jieduo Decoction on regulating triggering receptor expressed on myeloid cells 2(TREM2)/protein kinase B(Akt)/glycogen synthase kinase 3β(GSK3β) pathway to improve the cognitive deficit in APP/PS1 transgenic mice. APP/PS1 mice of approximately nine months old were randomly divided into the model group, the low, medium, and high(2.5, 5, and 10 g·kg(-1)) groups of Huanglian Jiedu Decoction, and 0.75 mg·kg(-1) donepezil hydrochloride group, and the C57BL/6J mice with the same age were taken as the normal group. After one month of continuous oral administration, a Morris water maze was performed to detect the learning and memory ability of mice. Hematoxylin-eosin(HE) staining was applied to observe the morphology of neuronal cells in the cortical area of mice. Immunofluorescence was used to detect the protein expressions of β-amyloid(Aβ_(1-42)), CD86, and arginase 1(Arg1). The mRNA levels of interleukin(IL)-1β, IL-6, and IL-10 in the cortex of mice were detected by real-time fluorescence quantitative polymerase chain reaction(RT-qPCR). The protein expressions of TREM2, phosphoinositide-3 kinase(PI3K), Akt, GSK3β, and beta-catenin(β-catenin) in mouse cortex were determined by Western blot. The results indicated that the escape latency of the model group was significantly prolonged, and the residence time in the target quadrant and the number of crossing the platform were significantly reduced compared with the normal group. Mice in the model group had a significantly lower number of neurons in the cortex and showed nuclear pyknosis and a significant increase in the expressions of Aβ_(1-42) and CD86. The mRNA levels of IL-1β and IL-6 in tissue were significantly increased, IL-10 were increased, while Arg1 were significantly decreased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3β(Ser9), and β-catenin in the cortex were significantly down-regulated. Compared with the model group, the escape latency of the mice in the administration group was significantly shortened, and the number of crossing the platform and the residence time in the target quadrant were significantly increased. Furthermore, the number of neurons in the cortex of mice was increased, and nuclear pyknosis was improved. Aβ_(1-42) deposition was decreased significantly. The mRNA levels of IL-1β, IL-6 and CD86 were significantly decreased, while IL-10 and Arg1 levels were significantly increased. The expression of TREM2, p-PI3K(Y607), p-Akt(T308), p-GSK3β(Ser9), and β-catenin protein in the cortex of each administration group was significantly up-regulated compared with the model group. In conclusion, Huanglian Jiedu Decoction reduced the expression of Aβ_(1-42) and neuroinflammation to a neuro-protective effect, thereby improving the learning and memory ability in APP/PS1 mice, which may be related to the TREM2/Akt/GSK3β signaling pathway.
黄连解毒汤治疗以“毒损脑络”为特征的阿尔茨海默病（AD）的中医作用机制尚不清楚。本研究旨在探讨黄连解毒汤通过调节髓系细胞触发受体2（TREM2）/蛋白激酶B（Akt）/糖原合酶激酶3β（GSK3β）通路改善APP/PS1转基因小鼠认知缺陷的机制。将约9月龄的APP/PS1小鼠随机分为模型组、黄连解毒汤低、中、高剂量（2.5、5、10 g·kg⁻¹）组和0.75 mg·kg⁻¹盐酸多奈哌齐组，将同龄C57BL/6J小鼠作为正常组。连续灌胃1个月后，进行Morris水迷宫实验检测小鼠的学习记忆能力。采用苏木精-伊红（HE）染色观察小鼠皮质区神经元细胞形态。采用免疫荧光法检测β淀粉样蛋白（Aβ₁₋₄₂）、CD86和精氨酸酶1（Arg1）的蛋白表达。采用实时荧光定量聚合酶链反应（RT-qPCR）检测小鼠皮质中白细胞介素（IL）-1β、IL-6和IL-10的mRNA水平。采用蛋白质印迹法检测小鼠皮质中TREM2、磷酸肌醇-3激酶（PI3K）、Akt、GSK3β和β连环蛋白（β-catenin）的蛋白表达。结果显示，与正常组相比，模型组小鼠的逃避潜伏期显著延长，在目标象限的停留时间和穿越平台的次数显著减少。模型组小鼠皮质神经元数量显著减少，出现核固缩，Aβ₁₋₄₂和CD86表达显著增加。组织中IL-1β和IL-6的mRNA水平显著升高，IL-10升高，而Arg1显著降低。皮质中TREM2、p-PI3K（Y607）、p-Akt（T308）、p-GSK3β（Ser9）和β-catenin的表达显著下调。与模型组相比，给药组小鼠的逃避潜伏期显著缩短，穿越平台的次数和在目标象限的停留时间显著增加。此外，小鼠皮质神经元数量增加，核固缩得到改善。Aβ₁₋₄₂沉积显著减少。IL-1β、IL-6和CD86的mRNA水平显著降低，而IL-10和Arg1水平显著升高。各给药组皮质中TREM2、p-PI3K（Y607）、p-Akt（T308）、p-GSK3β（Ser9）和β-catenin蛋白表达均较模型组显著上调。综上所述，黄连解毒汤降低Aβ₁₋₄₂表达和神经炎症发挥神经保护作用，从而改善APP/PS1小鼠的学习记忆能力，这可能与TREM2/Akt/GSK3β信号通路有关。
