【摘要】 目的:利用db/db转基因小鼠模型探究二甲双胍联合小檗碱对糖尿病认知功能障碍的改善作用。方法:将db/db小鼠随机分为模型组（M）、二甲双胍给药组（Mt）、小檗碱给药组（Bb）和二甲双胍联合小檗碱给药组（MB）,将同窝出生的db/m小鼠设为空白对照组（C）。分别灌胃给药二甲双胍(300 mg·kg^-1)、小檗碱(135 mg·kg^-1)、二甲双胍联合小檗碱(300 mg·kg^-1+135 mg·kg^-1)10周,测定各组db/db小鼠体重、血糖及其相关指标、行为学、氧化应激和炎症因子相关指标;并用苏木素-伊红染色处理脑组织切片,光镜观察病理学改变;利用基质辅助激光解析电离质谱成像（matrix-assisted laser desorption ionization time-of-flight mass spectrometry imaging, MALDI-TOF-MSI）技术观察小鼠脑组织代谢小分子含量的变化。结果:MB组小鼠空腹血糖值明显低于M组,且低于Mt和Bb组小鼠血糖。水迷宫实验中,和M组小鼠比较,MB组小鼠逃避潜伏期和从对侧象限入水找到平台的时间明显变短;90 s内穿台次数和在目标象限中停留时间明显增多。在外周血清ELISA测定中,MB组小鼠对比M组小鼠HbA1c, 8-OHdG,PCO,TNF-α,NLRP3和IL-1β水平均明显降低,IL-6水平明显升高。在HE染色实验中,和M组小鼠比较,MB组小鼠脑海马区中神经细胞排列整齐,形态较完整,核染色清晰,细胞间界限清楚。在质谱成像实验中,和M组小鼠比较,MB组小鼠脑天冬氨酸、N-乙酰-天冬氨酸、谷氨酸水平明显上升且高于Mt和Bb组;牛磺酸、葡萄糖水平明显降低且低于Mt和Bb组。结论:本实验证明了二甲双胍联合小檗碱口服给药对糖尿病认知功能障碍有改善作用,且比单独给药二甲双胍或小檗碱效果更明显,其作用机制或与抗炎、抗氧化应激、改善TCA循环以及提高兴奋性氨基酸水平等相关。更多还原

【Abstract】 Objective: To explore the protective effects of metformin plus berberine against diabetes-induced cognitive dysfunction in db/db mice. Methods: Mice were randomly divided into model, metformin, berberine, and metformin plus berberine（MB） groups. Db/m mice born in the same litter were used as the control group. Metformin(300 mg·kg^-1) and berberine(135 mg·kg^-1), either alone or in combination, were administered orally for 10 weeks. Body weight, blood glucose and related indices, and behavioral, oxidative stress-related, and inflammatory factor-related indexes of db/db mice were measured. Brain tissue sections were subjected to hematoxylin-eosin（HE） staining, and pathological changes were observed via light microscopy. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to observe changes in the levels of small molecules in the brain tissue. Results: Fasting blood glucose levels were significantly lower in the MB group than in the model, metformin, and berberine groups after 8 and 10 weeks of dosing. In the Morris water maze test, escape latency and time to find the platform from the contralateral quadrant were significantly shorter in the MB group than in the model group. The number of target crossings in 90 s and residence time in the target quadrant significantly increased in the metformin plus berberine group. According to ELISA, glycated hemoglobin, 8-hydroxydeoxyguanosine, protein carbonyl, tumor necrosis factor-α, NLRP3, and interleukin-1β levels were significantly lower in the MB group than in the model group, whereas interleukin-6 levels significantly increased. In HE staining experiments, compared with the model group, the neurons in the hippocampal region in the metformin plus berberine group were arranged neatly, with more complete shape, clear nuclear staining, and clear cell boundaries. In mass spectrometry imaging experiments, brain aspartate, N-acetyl-aspartate, and glutamate levels were significantly higher in the MB group than in the model group, whereas taurine and glucose levels significantly decreased. Conclusion: Oral administration of MB has protective effects on diabetes-induced cognitive dysfunction and stronger effects than using either drug alone. The mechanism of action may be related to anti-inflammatory and antioxidative stress effects and increase in excitatory amino acids levels.更多还原