光辉霉素A调节肾上腺髓质素表达改善帕金森病模型小鼠行为学异常  

Mithramycin A improves behavioral abnormalities in Parkinson’s disease mice through adrenomedullin expression inhibition

作　　者：姚璐[1,2] 周艳楠 王勇 闫翀 赵天宇 王会生 王星惠 戴星 YAO Lu;ZHOU Yannan;WANG Yong;YAN Chong;ZHAO Tianyu;WANG Huisheng;WANG Xinghui;DAI Xing(Department of Orthopaedics,First Affiliated Hospital,Xi’an Jiaotong University,Xi’an 710061,China;Department of Physiology and Pathophysiology,School of Basic Medical Sciences,Health Science Center,Xi’an Jiaotong University)

机构地区：[1]西安交通大学第一附属医院骨科,西安710061 [2]西安交通大学医学部基础医学院生理学与病理生理学系

出　　处：《山西医科大学学报》2019年第10期1413-1417,共5页Journal of Shanxi Medical University

基　　金：国家自然科学基金资助项目(31300899,81702699);陕西省重点研发计划项目(2017SF-231);陕西省自然科学基础研究计划项目(2018JM7035);中央高校基本科研业务费项目(XJJ2018046);陕西省大学生创新创业训练计划项目;西安交通大学本科教学实验中心(室)开放实验项目

摘　　要：目的探讨光辉霉素A(mithramycin A,MMA)通过调节肾上腺髓质素(adrenomedullin,ADM)表达改善帕金森病(Parkinson’s disease,PD)模型小鼠行为学异常的机制。方法12.5周龄雄性C57BL/6小鼠40只随机分为对照组,1-甲基-4-苯基-1,2,3,6-四氢吡啶(1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine,MPTP)毒性组,MMA与MPTP联合注射组和MMA单独注射组。采用腹腔注射MPTP的方法建立PD小鼠模型。造模成功后进行小鼠自主活动和避暗实验行为学检测,记录小鼠穿格次数、站立次数及避暗实验潜伏期。同时使用TH免疫荧光染色检测小鼠中脑纹状体多巴胺能神经纤维密度,采用ELISA方法检测小鼠纹状体中ADM表达水平。并进一步在1-甲基-4-苯基-吡啶离子(1-methyl-4-phenylpyridinium,MPP+)诱导的SH-SY5Y细胞PD模型中通过染色质免疫共沉淀(chromatin immunoprecipitation,ChIP)实验观察SP1与ADM启动子DNA结合及转录活性变化。结果与对照组相比,MPTP毒性组避暗实验潜伏期显著缩短(P<0.05)。MMA单独注射组与对照组相比在小鼠行为学检测中未见明显变化。MMA+MPTP组则显著改善了MPTP造成的避暗实验潜伏期的缩短(P<0.05)。MMA单独注射组纹状体TH免疫荧光显示MPTP导致纹状体中多巴胺能神经纤维密度降低(P<0.05),但MMA可以明显减少TH阳性神经纤维密度信号丢失(P<0.05)。ELISA结果显示MPTP毒性升高了小鼠纹状体中ADM的水平(P<0.05),当联合注射MMA后可以使升高的ADM水平降低(P<0.05)。此外,ChIP结果提示了MMA可以抑制MPP+诱导的SP1与ADM启动子结合转录活性的增强。结论MMA通过抑制SP1转录活性调控肾上腺髓质素表达,对PD模型小鼠具有神经保护作用。Objective To explore the mechanism of the improvement of behavioral abnormalities in Parkinson’s disease(PD)mice through inhibition of adrenomedullin(ADM)expression by mithramycin A.Methods Forty 12.5-week-old male C57BL/6 mice were randomly divided into control group,MPTP group,MMA+MPTP group and MMA group.PD mouse models were established by intraperitoneal injection of MPTP.Behavioral tests were conducted,including independent activities and dark avoidance experiments.TH immunofluorescence staining was used to detect the density of dopaminergic nerve fiber in the striatum of brain,and ELISA was used to detect the striatum ADM expression after successful modeling.Furthermore,the binding and transcription activity of SP1 to the ADM promoter were further observed in the MPP+-induced SH-SY5Y PD cell model by ChIP analysis.Results Compared with control group,the incubation period was shortened in the dark avoidance experiment in MPTP group(P<0.05).And the behavioral abnorma-lities were significantly alleviated in MMA+MPTP group compared with MPTP group(P<0.05),but there was no significant difference between MMA group and control group.TH immunofluorescence showed that MPTP toxicity reduced the density of dopaminergic nerve fibers in the striatum(P<0.05),and MMA alleviated the density signal decrease of TH positive nerve fibers(P<0.05).ELISA tests showed that MPTP toxicity also increased levels of ADM expression in the striatum(P<0.05),which was reduced by MMA injection(P<0.05).In addition,ChIP results showed that MMA inhibited the enhanced binding and transcription activity of SP1 to the ADM promoter induced by MPP+in PD models.Conclusion MMA could regulate the adrenomedulin expression by inhibiting the transcriptional activity of SP1,and have neuroprotective effects in PD mice models.

关 键 词：肾上腺髓质素 神经保护 帕金森病 转录因子SP1 

分 类 号：R742[医药卫生—神经病学与精神病学]