Ye Qing, Yuan Xiaolei, Zhou Jie, Yuan Canxing, Yang Xuming
J Tradit Chin Med. 2017 Apr;37(2):244-51. doi: 10.1016/s0254-6272(17)30051-1.
To investigate the regulatory mechanism of the c-Jun N-terminal protein kinase (JNK) signaling pathway in substantia nigra (SN) dopaminergic neurons inflammation and apoptosis, and the neuroprotective effect of Zishenpingchan granules in mice with Parkinson's disease (PD) induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).
PD model mice were established by intraperitoneally injecting MPTP. Sixty mice were divided into a model group, Traditional Chinese Medicine (TCM) group and control group. The mice of the TCM group were administered Zishenpingchan granules 7 days before PD induction. Seven days after PD induction, we examined locomotor activity, and performed the rotarod test and swimming test, to evaluate limb movement function. Furthermore, we used immunohistochemistry and western blotting to examine the expression of tyrosine hydroxylase (TH), cyclooxygenase-2 (Cox-2), caspase-3 and p-JNK. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method was used to examine neuron apoptosis in the SN.
Compared with the control group, the mean score of locomotor activity, rotarod test and swimming test was significantly lower in the model group (P < 0.05); the TH-positive neuron expression was significantly decreased in the SN pars compacta (SNpc); the protein expression levels of Cox-2, caspase-3 and p-JNK was obviously increased; and the number of TUNEL-positive neurons in the SN was increased (P < 0.01). Compared with the model group, the mean score of neurobehavioral tests in the TCM group was obviously higher, the loss of TH-positive neurons ignificantly decreased, the protein expression levels of Cox-2, caspase-3 and p-JNK obviously decreased, and the number of TUNEL- positive neurons in the SN clearly decreased (P < 0.01).
The JNK pathway plays an important role in the regulation of inflammation and apoptosis in nigral cells in PD mice. TCM can suppress the over-activation of the JNK pathway in the SN, and alleviate the inflammatory response in nigral cells and dopaminergic neuron apoptosis in PD mice.
探讨c-Jun氨基末端蛋白激酶（JNK）信号通路在黑质（SN）多巴胺能神经元炎症和凋亡中的调控机制，以及滋肾平颤颗粒对1-甲基-4-苯基-1,2,3,6-四氢吡啶（MPTP）诱导的帕金森病（PD）小鼠的神经保护作用。
通过腹腔注射MPTP建立PD模型小鼠。将60只小鼠分为模型组、中药组和对照组。中药组小鼠在诱导PD前7天给予滋肾平颤颗粒。PD诱导7天后，检测运动活性，进行转棒试验和游泳试验，以评估肢体运动功能。此外，采用免疫组织化学和蛋白质印迹法检测酪氨酸羟化酶（TH）、环氧化酶-2（Cox-2）、半胱天冬酶-3（caspase-3）和磷酸化JNK（p-JNK）的表达。采用末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）法检测SN中的神经元凋亡。
与对照组相比，模型组运动活性、转棒试验和游泳试验的平均得分显著降低（P<0.05）；致密部黑质（SNpc）中TH阳性神经元表达显著减少；Cox-2、caspase-3和p-JNK的蛋白表达水平明显升高；SN中TUNEL阳性神经元数量增加（P<0.01）。与模型组相比，中药组神经行为学试验的平均得分明显更高，TH阳性神经元的损失显著减少，Cox-2、caspase-3和p-JNK的蛋白表达水平明显降低，SN中TUNEL阳性神经元数量明显减少（P<0.01）。
JNK通路在PD小鼠黑质细胞炎症和凋亡的调控中起重要作用。中药可抑制SN中JNK通路的过度激活，减轻PD小鼠黑质细胞的炎症反应和多巴胺能神经元凋亡。
