目的 探讨左归降糖解郁方（ZGF）对自噬介导的糖尿病并发抑郁症（diabetes mellitus with depression，DD）大鼠海马神经血管单元（neurovascular unit，NVU）中神经元的保护作用及其机制。方法 原代分离、纯化和培养SD大鼠海马神经元、星形胶质细胞及脑微血管内皮细胞，构建海马NVU体外共培养体系，并进行免疫细胞化学染色鉴定。采用高糖（150 mmol/L）联合皮质酮（200 μmol/L）干预制备海马NVU细胞模型，实验设对照组、模型组、空白血清对照组和ZGF含药血清组。采用Furo-3/AM染色法检测海马NVU神经元细胞内钙水平，高内涵细胞成像分析技术（high content analysis，HCA）检测海马NVU神经元细胞内自噬标志物自噬相关蛋白1（Beclin-1）、人微管相关蛋白轻链3Ⅱ（LC3-Ⅱ）及谷氨酸受体2（GluR2）/Ca²⁺/哺乳动物雷帕霉素靶蛋白（mTOR）信号通路关键蛋白的表达，TUNEL染色法观察各组海马神经元细胞凋亡。结果 与对照组比较，模型组及空白血清对照组海马NVU神经元细胞内钙水平显著升高，自噬标志物Beclin-1、LC3-Ⅱ蛋白表达水平显著升高，GluR2、mTOR蛋白表达水平显著降低，AMP依赖的蛋白激酶（AMPK）蛋白表达水平显著升高，且细胞凋亡明显增多；与模型组比较，ZGF含药血清组海马NVU神经元细胞内钙水平明显降低，自噬标志物Beclin-1、LC3-Ⅱ蛋白表达水平降低，GluR2/Ca²⁺/mTOR信号通路中GluR2、mTOR蛋白表达水平升高，AMPK蛋白表达水平降低，同时细胞凋亡显著减少。结论 ZGF对自噬介导的DD大鼠海马NVU神经元细胞损伤具有明显的保护作用，其作用机制与调控GluR2/Ca²⁺/mTOR信号通路及细胞凋亡有关。

Objective To investigate the protective effects and mechanism of Zuogui Jiangtang Jieyu Formulation (ZGF) on hippocampal neuron of neurovascular unit (NVU) induced by autophagy in diabetes mellitus with depression (DD). Methods Hippocampal neurons, astrocytes and brain microvascular endothelial cells from SD rats were primitively isolated, purified and cultured, and then immunocytochemistry staining was employed to identify primitive cells. The DD model of NVU was established by applying intervention of high glucose (150 mmol/L) and cortisone (200 μmol/L) after co-culture system was built in vitro. The cultured cells were randomly divided into normal group, blank serum group, model group, and medicated serum of ZGF group. Intracellular calcium levels (Ca²⁺) on hippocampal neuron of NVU was detected by Furo-3/AM staining. The expression of autophagy marker Beclin-1, LC3-Ⅱ, and GluR2/Ca²⁺/mTOR signaling pathway key proteins was detected by high content analysis. The apoptosis of hippocampal neurons was observed by Tunel staining. Results Compared with the normal group, Ca²⁺ levels was remarkably increased, expression of autophagy marker Beclin-1 and LC3-Ⅱ was dramatically up-regulated, proteins expression of GluR2 and mTOR was obviously down-regulated while AMPK up-regulated, and the apoptosis in hippocampal neuron of NVU was significantly increased in model and blank serum group. Compared with the model group, intracellular calcium levels was obviously decreased, expression of autophagy marker Beclin-1 and LC3-Ⅱ was down-regulated, GluR2/Ca²⁺/mTOR signaling pathway proteins expression of GluR2, mTOR was up-regulated while AMPK down-regulated, furthermore the apoptosis of hippocampal neurons was significantly decreased in ZGF group. Conclusion ZGF has significant protective effects on hippocampal neuron of NVU induced by autophagy in DD, and its mechanism is related to the GluR2/Ca²⁺/mTOR signaling pathway and apoptosis.

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国家自然科学基金资助项目（81573965）；国家自然科学基金资助项目（81703694）；湖南省自然科学基金项目（2017JJ3241）；湖南省教育厅科学研究项目（17C1229）；湖南中医药大学中医学一流学科开放基金（2018ZYX47）