人脐带血血浆外泌体调控帕金森病小鼠免疫反应发挥神经保护作用的研究

Neuroprotective effect of human umbilical cord blood-derived exosomes in Parkinson disease mice via modulating immunity

目的:观察人脐带血血浆外泌体(UCB-Exos)对帕金森病小鼠模型运动功能的影响,探究其免疫干预作用和神经保护机制。方法:改良超速离心法分离UCB-Exos,透射电镜、动态光散射技术和Western blot法进行鉴定。将C57BL/6小鼠随机分为对照组、模型组[腹腔注射1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)造模]、治疗组(造模后尾静脉注射UCB-Exos)和预保护组(造模前尾静脉注射UCB-Exos)。检测小鼠运动功能变化;免疫组化检测小鼠黑质区酪氨酸羟化酶(TH)、离子钙结合衔接分子1(IBA-1)和胶质细胞原纤维酸性蛋白(GFAP)的表达;流式细胞术分析小鼠外周血淋巴细胞和巨噬细胞的变化;RT-qPCR和ELISA检测小鼠脑组织炎症因子的表达水平。结果:与模型组相比,治疗组和预保护组小鼠运动功能显著改善,黑质区TH表达水平升高,IBA-1和GFAP表达水平降低,脑组织白细胞介素6(IL-6)、IL-1β和IL-18表达水平显著降低,IL-10表达水平升高。流式细胞术结果显示,经UCB-Exos处理后,小鼠外周血T淋巴细胞亚群比例发生改变。结论:UCB-Exos调节免疫反应,减轻神经炎症,从而缓解帕金森病小鼠的运动功能障碍。

AIM:To observe the effect of human umbilical cord blood plasma-derived exosomes(UCB-Exos)on motor function of Parkinson disease model mice,and to explore the potential immunoregulatory and neuroprotective mechanisms.METHODS:The UCB-Exos were isolated using ultracentrifugation,and characterized via transmission electron microscopy,transmission dynamic light scattering and Western blot.The C57BL/6 mice were randomly divided into control group,model[1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)]group(intraperitoneal injection of MPTP for modeling),treatment(MPTP+UCB-Exos)group(injection of UCB-Exos via the tail vein after modeling),and preprotection(pro-UCB-Exos+MPTP)group(injection of UCB-Exos via the tail vein before modeling).Motor function of the mice was assessed.Immunohistochemistry was used to measure the expression of tyrosine hydroxylase(TH),ionized calcium-binding adapter molecule-1(IBA-1)and glial fibrillary acidic protein(GFAP)in the substantia nigra.Flow cytometry was used to analyze the changes of peripheral blood lymphocyte and macrophage subsets.RT-qPCR and ELISA were used to detect the expression of inflammatory factors in brain tissues.RESULTS:Compared with model group,the mice in MPTP+UCB-Exos and pro-UCB-Exos+MPTP groups exhibited significantly improved motor function,as well as an increase in TH expression and a decrease in IBA-1 and GFAP expression in the substantia nigra.Additionally,the expression levels of interleukin-6(IL-6),IL-1βand IL-18 were significantly decreased in brain tissues,while the expression of IL-10 was increased.Flow cytometry analysis revealed that the proportions of peripheral T-lymphocyte subsets were significantly altered in MPTP+UCB-Exos and pro-UCB-Exos+MPTP groups compared with model group.CONCLUSION:The UCB-Exos modulate peripheral immunity and alleviate neuroinflammation,thus improving the motor function in MPTP-induced Parkinson disease mouse model.