基于小胶质细胞-神经元串扰信号CD300f/TLR4探讨左归降糖解郁方对糖尿病并发抑郁症大鼠海马突触微环境损伤的保护作用及机制  

Protective effect and mechanism of Zuogui Jiangtang Jieyu Formula on damage to hippocampal synaptic microenvironment in rats with diabetes-related depression based on microglia-neuron crosstalk signal CD300f/TLR4

作　　者：刘检[1] 杨蕙[1] 赵洪庆 李薇[1] 柳卓[4] 王宇红 LIU Jian;YANG Hui;ZHAO Hong-qing;LI Wei;LIU Zhuo;WANG Yu-hong(Center for Medical Research and Innovation,the First Hospital of Hunan University of Chinese Medicine,Changsha 410007,China;Hunan Key Laboratory of Traditional Chinese Medicine Prevention and Treatment of Depressive Diseases,Changsha 410208,China;Science&Technology Innovation Center,Hunan University of Chinese Medicine,Changsha 410208,China;the Affiliated Hospital of Hunan Academy of Traditional Chinese Medicine,Changsha 410006,China)

机构地区：[1]湖南中医药大学第一附属医院医学创新实验中心,湖南长沙410007 [2]抑郁类疾病中医药防治湖南省重点实验室,湖南长沙410208 [3]湖南中医药大学科技创新中心,湖南长沙410208 [4]湖南省中医药研究院附属医院,湖南长沙410006

出　　处：《中国中药杂志》2024年第17期4597-4606,共10页China Journal of Chinese Materia Medica

基　　金：国家自然科学基金青年科学基金项目(82104793,82104839);湖南省自然科学基金面上项目(2022JJ30451);湖南省自然科学基金优秀青年项目(2024JJ4033);湖南省自然科学基金医卫联合项目(2024JJ9427);湖南省三尖创新人才工程湖湘青年英才项目(2022RC1226)。

摘　　要：探讨左归降糖解郁方调控小胶质细胞免疫受体分子样家族成员f(CD300f)/Toll样受体4(TLR4)信号改善糖尿病并发抑郁症(DD)大鼠海马突触微环境损伤的保护作用及机制。首先通过2周高脂饲料喂养+STZ注射+28 d慢性温和不可预测性应激加孤养复制DD大鼠模型,实验设正常组、模型组、CD300f阻断剂组(CLM1,2μg·kg-1)、CD300f激动剂组(Fcγ,5μg·kg^(-1))、阳性药组(二甲双胍0.18 g·kg^(-1)+氟西汀1.8 mg·kg^(-1))以及左归降糖解郁方高、低剂量组(20.52、10.26 g·kg^(-1))。采用旷场、强迫游泳实验评估大鼠抑郁样行为;生化分析检测血糖、胰岛素水平;酶联免疫吸附法检测海马组织中肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1β、吲哚胺2,3-双加氧酶(IDO)、5-羟色胺(5-HT)、多巴胺(DA)水平;透射电镜观察大鼠海马神经元突触超微结构变化情况;免疫荧光、Western blot分别检测大鼠海马小胶质细胞中CD300f、TLR4及海马神经元中突触素(SYN)、突触后密度蛋白95(PSD-95)表达情况。结果表明,与正常组比较,模型组大鼠旷场总活动路程减少,强迫游泳不动时间增加,血清胰岛素、海马组织中TNF-α、IL-1β、IDO水平升高,而5-HT和DA水平明显下降,且海马小胶质细胞中CD300f表达下调、TLR4表达上调,海马神经元中突触相关蛋白SYN、PSD-95表达降低,同时海马神经元突触超微结构明显受损;与模型组比较,CD300f阻断剂和激动剂分别加重和减轻上述异常改变;左归降糖解郁方高、低剂量则能显著改善大鼠上述抑郁样行为,分别抑制TNF-α、IL-1β、IDO异常升高和5-HT、DA减少,并有效增加小胶质细胞中CD300f表达,降低TLR4表达,上调海马神经元中突触前膜SYN和突触后膜PSD-95蛋白表达水平,最终改善海马突触微环境损伤。综上,该文证实了左归降糖解郁方能有效改善糖尿病并发抑郁症大鼠抑郁样行为,抑制海马小胶质细胞炎症激活,其机制可能与调This study aims to reveal the protective effect and mechanism of Zuogui Jiangtang Jieyu Formula on the damage to hippocampal synaptic microenvironment in rats with diabetes-related depression(DD)via regulating microglia immune receptor moleculelike family member f(CD300f)/Toll-like receptor 4(TLR4)signal.Firstly,the model of DD rats was established by a two-week highfat diet+STZ injection+chronic mild and unpredictable stress plus isolation for 28 days.The rats were randomly divided into normal group,model group,CD300f blocker(CLM1,2μg·kg^(-1))group,CD300f agonist(Fcγ,5μg·kg^(-1))group,positive drug(0.18 g·kg^(-1)metformin+1.8 mg·kg^(-1)fluoxetine)group,and high-dose and low-dose(20.52 and 10.26 g·kg^(-1))Zuogui Jiangtang Jieyu Formula groups.Depression-like behavior of rats was evaluated by open field and forced swimming experiments.The levels of blood glucose and insulin were detected by biochemical analysis.The levels of tumor necrosis factorα(TNF-α),interleukin-1β(IL-1β),indoleamine 2,3-dioxygenase(IDO),5-hydroxytryptamine(5-HT),and dopamine(DA)in the hippocampus were detected by enzyme-linked immunosorbent assay.The changes in the synaptic ultrastructure in hippocampal neurons of rats were observed by transmission electron microscopy.The protein expressions of CD300f,TLR4,synaptophysin(SYN),and postsynaptic density protein 95(PSD-95)in microglial cells of the hippocampus were detected by immunofluorescence and Western blot.The results indicated that compared with that in the normal group,the total movement distance in open field experiments was reduced in the model group,and the immobility time in forced swimming experiments increased,with an elevated insulin level in serum,as well as TNF-α,IL-1β,and IDO levels in the hippocampus.The 5-HT and DA levels in the hippocampus were reduced.In addition,the CD300f expression was downregulated in microglial cells of the hippocampus,and the TLR4 expression was up-regulated.Moreover,the expression of synapse-related proteins SYN and PSD-95 in hippocampal

关 键 词：糖尿病并发抑郁症 小胶质细胞 CD300f/TLR4 突触微环境 左归降糖解郁方 

分 类 号：R285.5[医药卫生—中药学]