Objectives: To observe the effect of electroacupuncture (EA) on ferroptosis and apoptosis-related proteins in the substantia nigra of midbrain in mice with Parkinson's disease (PD), so as to explore its possible mechanisms in the treatment of PD.
Methods: Twenty-four C57BL/6 mice were randomly divided into blank, model and EA groups, with 8 mice in each group. The PD model was established by continuous gavage of rotenone for 4 weeks. EA was applied at "Baihui" (GV20), "Quchi" (LI11) and "Zusanli" (ST36) for 20 min, once a day for 14 days, with 2-day rest after every 5-day treatment. The open field test was used to evaluate the residence time in the central area, ave-rage movement speed, and total distance of the open field. Western blot was used to detect the protein expression le-vels of divalent metal ion transporter 1 (DMT1), membrane ferroportin 1 (FPN1), glutathione peroxidase 4 (GPX4), proapoptotic protein Bax, and anti apoptotic protein Bcl-2 in the substantia nigra. Immunohistochemical method was used to detect the morphological changes of neurons and the positive expression of tyrosine hydroxylase (TH) in the substantia nigra of mice.
Results: After 4 weeks of modeling, compared with the blank group, the residence time in the central area, average speed and total distance of open field were significantly lower (P<0.000 1, P<0.01, P<0.001)；the protein expression levels of DMT1 and Bax in the substantia nigra were increased (P<0.001, P<0.000 1), while the protein expression levels of FPN1, GPX4 and Bcl-2, and the optical density of TH+ cells in the substantia nigra were decreased (P<0.000 1, P<0.001) in the model group. In comparison with the model group, the residence time in the central area, average speed, and total distance of the EA group were increased (P<0.01, P<0.05)；the protein expression levels of DMT1 and Bax in the substantia nigra were decreased (P<0.01, P<0.001), while the protein expression levels of FPN1, GPX4, and Bcl-2, and the optical density of TH+ cells in the substantia nigra were increased (P<0.000 1, P<0.01, P<0.001, P<0.05).
Conclusions: EA has a protective effect on dopaminergic neurons in the substantia nigra of midbrain in PD model mice, which may be related with its effect in regulating oxidative stress and cell apoptosis induced by ferroptosis.
目的: 观察电针干预对帕金森病（PD）小鼠中脑黑质铁死亡及细胞凋亡相关蛋白的影响，探讨电针治疗PD的作用机制。方法: 将C57BL/6小鼠随机分为空白组、模型组及电针组，每组8只。采用鱼藤酮连续灌胃4周构建PD小鼠模型。电针组于造模成功后针刺“百会”，电针“曲池”“足三里”，20 min/次，1次/d，每治疗5 d休息2 d，共14 d。分别在造模前、造模后和电针干预结束后以旷场实验检测小鼠旷场中心区域停留时间、平均运动速度及运动总距离。干预结束后用Western blot法检测小鼠黑质二价金属离子转运体1（DMT1）、膜铁转运蛋白1（FPN1）、谷胱甘肽过氧化物酶4（GPX4）、促凋亡蛋白Bax、抗凋亡蛋白Bcl-2的蛋白表达水平；免疫组织化学法检测小鼠黑质神经元形态变化及酪氨酸羟化酶（TH）阳性表达。结果: 与空白组比较，造模4周后模型组小鼠旷场中心区域停留时间、平均运动速度及运动总距离均减少（P<0.000 1，P<0.01，P<0.001）；黑质中DMT1、Bax蛋白表达水平均升高（P<0.001，P<0.000 1），FPN1、GPX4、Bcl-2蛋白表达水平及黑质内TH+细胞吸光度值均降低（P<0.000 1，P<0.001）。与模型组比较，电针组小鼠中心区域停留时间、平均运动速度及运动总距离均增加（P<0.01，P<0.05）；黑质中DMT1、Bax蛋白表达水平均降低（P<0.01，P<0.001），FPN1、GPX4、Bcl-2蛋白表达水平及黑质内TH+细胞吸光度值均升高（P<0.000 1，P<0.01，P<0.001，P<0.05）。结论: 电针干预对PD模型小鼠中脑黑质多巴胺能神经元具有保护作用，其作用机制可能是通过调节铁死亡诱导的氧化应激及细胞凋亡实现的。.
Keywords: Cell apoptosis; Electroacupuncture; Ferroptosis; Oxidative stress; Parkinson’s disease.