电针调节CD8+T细胞对帕金森病模型小鼠黑质区神经元损伤的保护机制研究

关键词：帕金森病  电针  CD8+T细胞  酪氨酸羟化酶  表型标记物CD103+T细胞  干扰素γ  颗粒酶B

Keywords:Parkinson's disease  electric acupuncture  CD8+T cell  tyrosine hydroxylase  phenotypic marker CD103+T cell  interferon γ  granzyme B

摘要：

      摘要 目的：观察早期电针干预对CD8+T细胞浸润帕金森病（Parkinson's disease， PD）模型小鼠黑质区酪氨酸羟化酶（tyrosine hydroxylase， TH）及CD8+T细胞相关细胞因子表达的影响，探讨早期电针对PD的神经元保护效应及机制。 方法：将雄性C57BL/6小鼠随机分为空白组、模型组、电针组、左旋多巴组，每组15只；除空白组外，其余各组均腹腔注射1-甲基-4-苯基-1，2，3，6-四氢吡啶（1-Methyl-4-phenyl-1，2，3，6-tetrahydropyridine， MPTP）构建PD小鼠模型。造模成功电针组选取“足三里”、“悬钟”进行干预14天，治疗结束后进行转棒、旷场测试，并观察黑质区TH表达及CD8+T细胞表型标记物CD103+T细胞、干扰素γ（IFNγ）蛋白及颗粒酶B（GzmB）蛋白的表达。 结果：造模结束后，模型组小鼠毛色暗淡无光，精神萧瑟，活动减少，肌肉颤动，而电针组及左旋多巴组小鼠精神状态良好。与模型组相比，电针组及左旋多巴组小鼠掉棒潜伏时间延长（P<0.01），运动总距离延长且经过区域中心的速度改善（P<0.01），黑质区TH阳性表达增加（P<0.01），CD8+CD103+T细胞共定位表达率降低（P<0.01），IFNγ含量下调（P<0.05，P<0.01），GzmB表达下降（P<0.05，P<0.01）。 结论：早期电针干预可以提高PD模型小鼠的运动能力，增加黑质区TH表达并改善神经元损伤，其机制与电针减少黑质区CD8+CD103+T细胞浸润，进一步抑制IFNγ、GzmB分泌，最终降低细胞毒性并提高机体免疫功能有关。

Abstract:

      Abstract Objective：To investigate the effect of early electroacupuncture intervention on CD8+T cells infiltrating tyrosine hydroxylase（TH）and expression of CD8+T cell-related cytokines in substantia nigra of Parkinson's disease （PD） model mice. To investigate the neuronal protective effect and mechanism of early electrotherapy on PD. Method： Male C57BL/6 mice were randomly divided into four groups: blank group， model group， electroacupuncture group and the levodopa group， with 15 mice in each group. PD mouse model was established by intraperitoneal injection of 1-methyl-4-phenyl-1，2，3，6-tetrahydropyridine（MPTP） except for the blank group. In the EA group， "Zusanli" and "Hanging Zhong" were selected for intervention for 14 days. After the treatment， the rod-shifting and open-field tests were performed to observe the expression of TH and CD8+T cell phenotype markers CD103+T cells， interferon γ （IFNγ） protein and granzyme B （GzmB） protein in the substantia nigra. Result： At the end of the modeling， the mice in the model group had dull coat color， bleak spirit， decreased activity and muscle fibrillation， while the mice in the EA and levodopa groups were in a good mental state. Compared with the model group， the EA group and the levodopa group had prolonged rod dropping latency （P<0.01）， prolonged total distance and improved speed through the regional center （P<0.01）， increased TH positive expression in substantia nigra （P<0.01）， and decreased CD8+CD103+T cell colocality expression rate （P<0.01）. The content of IFNγ was down-regulated （P<0.05， P<0.01）， and the expression of GzmB was down-regulated （P<0.05， P<0.01）. Conclusion： Early EA intervention can improve the exercise ability of PD model mice， increase the expression of TH in the substantia nigra， and improveneuronal injury. The mechanism is related to the reduction of CD8+CD103+T cell infiltration in the substantia nigra， further inhibition of IFNγ and GzmB secretion， and ultimately the reduction of cytotoxicity and improvement of immune function.