HIF-1α在颅脑损伤中的神经保护作用及其相关分子机制

发布时间：2018-04-10 12:41

  本文选题：创伤性颅脑损伤 + 缺氧诱导因子-1?　； 参考：《天津医科大学》2017年博士论文

【摘要】：目的:随着社会进步与经济的高速发展及国际局势的多变,因交通事故、生产意外、自然灾害、局部区域的战争等因素造成的创伤性颅脑损伤(Traumatic Brain Injury,TBI)的发病率越来越高,其致残率以及致死率逐年上升,特别是由于恶性车祸、生产事故以及杀伤性武器的使用所带来的中、重度TBI对患者伤害尤为巨大,同时也给家庭以及社会造成很大的伤害与不良影响。因此,对于TBI发病机制的研究以及对其给予有效的干预、治疗方法的探索越来越受到创伤外科、神经医学等多领域研究学者的关注。缺氧诱导因子-1?(hypoxia-inducible factor-1?,HIF-1?)与TBI的多种病理变化关系非常密切。在TBI后缺血缺氧的内环境中,HIF-1?对神经细胞的适应、存活、凋亡以及对神经血管的修复、再生等病理生理变化过程都起着重要的稳定与促进作用。基于此,本课题拟通过观察在TBI中HIF-1?是否也发挥着抑制炎症反应以及促进血管生成的作用,并通过调控HIF-1?进一步探讨其在TBI中可能存在的神经血管保护作用。方法:利用液压打击仪建立Wistar大鼠TBI模型,在造模前将实验动物随机分为假手术组、TBI组、HIF-1?沉默表达组以及对照病毒颗粒组。观察时相分别设置为模型制备后第3、7、14天(即急性期、亚急性期、慢性期三个时段):(1)通过改良神经功能缺损程度评分(mNSS)量表对TBI后的大鼠神志及功能缺损变化进行动态评估。(2)通过HE切片染色观察TBI脑损伤面积以及损伤区形态结构的变化;(3)通过Western Blot方法检测大鼠受伤脑组织HIF-1?及vWF的表达变化;(4)通过ELISA法检测脑组织MMP9、VEGF、TNF-α、IL-6、NF-κB的表达变化;(5)通过统计学观察HIF-1?对TBI神经功能的影响分析其神经保护作用,并初步探讨HIF-1?与血管生成、炎症反应相关的分子机制。结果:(1)HE染色显示TBI组脑水肿程度在第3天、第7天、第14天较HIF-1?沉默表达组均有所减轻(P0.05,P0.05,P0.05);而改良神经功能缺损评分水平在第7天、第14天TBI组较HIF-1?沉默表达组也均明显好转(P0.05,P0.05)。(2)TBI大鼠中,HIF-1?沉默慢病毒颗粒颅内微量注射预处理后,脑组织内HIF-1?与vWF表达水平在3天、7天、14天三个观察时相均较TBI组明显下降(P0.05,P0.05,P0.05),表明脑组织内HIF-1?沉默表达的成功,且可抑制脑血管生成。液压打击造成TBI后第3天,TBI组HIF-1?表达水平较HIF-1?沉默表达组与假手术组明显升高(P0.05,P0.05),到第7天与第14天仍然保持较高水平,第7天TBI组HIF-1?表达水平较HIF-1?沉默表达组与假手术组升高明显(P0.05,P0.05),第14天TBI组HIF-1?表达水平较HIF-1?沉默表达组与假手术组也均升高明显(P0.05,P0.05)。(3)HIF-1?沉默表达组在3天、7天、14天的VEGF活性表达水平与TBI组相比均明显下降(P0.05,P0.05,P0.05),而MMP-9活性水平在第3天小幅下降(P0.05)后,在第7天、第14天出现显著的降低(P0.05,P0.05)。(4)IL-6活性水平:TBI组与HIF-1?沉默表达组比较在第3天、第7天、第14天,三个时相点均明显降低(P0.05,P0.05,P0.05);TNF-α水平:TBI组较HIF-1?沉默表达组在第3天、第7天、第14天,三个时相也明显降低(P0.05,P0.05,P0.05);NF-κB激活程度在第3天、第7天、第14天,三个时相TBI组较HIF-1?沉默表达组明显减弱(P0.05,P0.05,P0.05)。结论:HIF-1?沉默表达组炎症反应抑制以及促进血管形成方面均较TBI组明显减弱,从而说明HIF-1?在TBI后可通过抑制炎症反应以及促进血管形成的双重调节机制降低脑水肿程度,保护脑组织、改善脑神经功能,促进TBI恢复。
[Abstract]:Objective: with the rapid development of economic and social progress and the changeable international situation, due to traffic accidents, production accidents, natural disasters, traumatic brain injury caused by local war and other factors (Traumatic Brain, Injury, TBI) the increasing incidence of the disability rate and the mortality rate increased year by year, especially since the malignant accidents, accidents and the use of weapons of destruction caused by severe injury to patients, TBI is particularly great, but also caused great harm and adverse effects to the family and society. Therefore, the study of TBI pathogenesis and effective intervention for the treatment of exploration, more and more trauma surgery researchers in many fields, such as neural medical attention. Hypoxia inducible factor -1 (hypoxia-inducible? Factor-1?, HIF-1?) are associated with a variety of pathological changes. The relationship between TBI in TBI after hypoxia ischemia In the HIF-1 environment,? Adaptation, on cell survival, apoptosis and repair the nerve and blood vessel pathological changes, regeneration process plays an important role in promoting stability and. Based on this, this paper through the observation of HIF-1 in TBI? Whether to inhibit inflammatory reaction and promote angiogenesis the role, and through the regulation of HIF-1? Further discusses the possible TBI in the protection of the nerves and blood vessels. Methods: the use of hydraulic percussion instrument to establish Wistar rat model of TBI, before modeling the experimental animal were randomly divided into sham operation group, TBI group, HIF-1 group and the expression of silence? Virus particles observed group. When the phase were set for the preparation of the model after 3,7,14 days (i.e., acute, subacute, chronic period of three hours): (1) by modified neurological severity scores (mNSS) scale of god records and function defect changes of rats after TBI. Dynamic assessment. (2) to observe the changes of TBI area of brain injury and the morphology damage zone by HE staining; (3) detected by Western Blot method in rats injured brain tissue HIF-1 expression and vWF?; (4) through the detection of brain tissue by ELISA MMP9, VEGF, TNF- alpha, IL-6, expression NF- K B; (5) through statistical observation of the neuroprotective effect of HIF-1? TBI analysis on the influence of neural function, and to explore HIF-1? And angiogenesis, molecular mechanism of inflammatory reaction. Results: (1) HE staining showed that TBI group of brain edema in third days, seventh days, fourteenth days HIF-1? Silent expression group were improved (P0.05, P0.05, P0.05); and the modified neurological score levels in seventh days, fourteenth days in TBI group than HIF-1 group also? Silencing expression were significantly improved (P0.05, P0.05). (2) HIF-1 TBI in rat? Silent lentivirus intracranial microinjection after the pretreatment, brain tissue H IF-1?涓巚WF琛ㄨ揪姘村钩鍦，

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