珠蛋白在缺血及氧化损伤条件下神经保护作用的研究

发布时间：2018-01-09 05:12

本文关键词：珠蛋白在缺血及氧化损伤条件下神经保护作用的研究　出处：《西北农林科技大学》2011年硕士论文　论文类型：学位论文

【摘要】：脑血管疾病是威胁我国人们健康的重大疾病之一,脑血管疾病的预防和治疗已经成为医学界的重大难题。缺血性脑中风是常见的脑血管病之一,其病因是脑血管狭窄或栓塞,导致脑部血流阻断,使脑组织缺血从而引起病理反应。我们采用常用的大脑中动脉阻塞模型(MCAO),研究脑缺血的治疗,旨在探索治疗脑缺血的新方案。同时,脑缺血中氧自由基是造成损伤的重要来源,我们利用多重PCR技术检测在自由基氧化环境下线虫中33个珠蛋白(Globin)的表达差异,旨在寻找清除自由基的新药品,为脑缺血提供新的治疗方案。血液稀释通过降低红细胞压积和血液粘稠度以改善微循环和组织供氧,能抑制缺血再灌注引起的脑损伤。为研究扩容性血液稀释对脑缺血再灌注损伤的影响。我们以成年雄性SD大鼠为对象,制备脑缺血再灌注损伤模型。以生理盐水为血液稀释剂,对模型大鼠进行扩容性血液稀释。在再灌注同时,通过尾静脉分别注射0.5、1.0、2.0ml的生理盐水进行扩容性血液稀释,用2, 3, 5-三苯基四氮唑(TTC)染色,然后以图像分析方法计算TTC染色面积和脑梗死体积。结果显示随着注射生理盐水体积的增加,脑梗死体积呈降低的趋势,注射2.0ml生理盐水组脑梗死体积显著低于对照组。说明扩容性血液稀释能显著减小大鼠脑缺血再灌注模型脑梗死体积,对大鼠脑缺血再灌注损伤具有保护作用。脑红蛋白(NGB)是新发现的在脊椎动物神经系统中特异表达的携氧珠蛋白家族的成员,研究发现脑缺血能促进脑红蛋白的表达,同时脑红蛋白的过量表达能抑制缺血引起的脑损伤。为研究脑红蛋白对脑缺血再灌注损伤的影响。我们以成年雄性SD大鼠为对象,制备脑缺血再灌注损伤模型。用NGB和TAT-NGB(融合导肽的NGB)对脑缺血再灌注模型大鼠进行干预。于再灌注同时,通过尾静脉分别注射不同浓度的NGB和TAT-NGB溶液。用2, 3, 5-三苯基四氮唑(TTC)染色,然后以图像分析方法计算TTC染色面积和脑梗死体积。结果显示注射NGB和TAT-NGB溶液的大鼠脑梗死体积相对对照组减小,在NGB剂量为24mg/kg和TAT-NGB剂量为10mg/kg时脑梗死体积显著减小。说明NGB能减小大鼠脑缺血再灌注模型的脑梗死体积,对缺血再灌注引起的大鼠脑损伤有保护作用。珠蛋白是几乎存在于各种生物中的氧结合蛋白,其共同的特点是都含有典型的螺旋三明治折叠结构。线虫体内存在33种珠蛋白,这些蛋白的功能还不清楚。为了研究线虫体内33种珠蛋白与活性氧自由基的关系。我们以N2野生型线虫为实验对象,饲养于含有不同浓度(0.3 mmol/L、0.4 mmol/L、0.5 mmol/L )百草枯(PQ)的线虫培养基(NGM)上,五天后,提取线虫的总RNA,再进行反转录。然后利用多重PCR技术扩增线虫33种珠蛋白,用凝胶定量分析软件计算各条带的积分光密度,计算出各个珠蛋白的相对表达量。通过与对照组比较,得出33种珠蛋白的表达变化。结果显示在PQ处理下表达增加的基因有:Globin-7、Globin -12、Globin -19、Globin -22、Globin -24、Globin -31。这些基因在PQ的压力下表达明显增高,这些蛋白具有抑制PQ引起的氧化损伤的潜在能力。
[Abstract]:Cerebrovascular disease is one of the major diseases threatening people's health in our country, the prevention and treatment of cerebrovascular disease has become a major problem in the medical field. The ischemic stroke is one of the most common cerebrovascular disease, its etiology is cerebral vascular stenosis or embolism, resulting in blocking blood flow to the brain, the cerebral ischemia causing pathological reaction. We use the brain artery occlusion model (MCAO), the treatment of cerebral ischemia, to explore the new scheme for the treatment of cerebral ischemia. At the same time, the oxygen free radicals in cerebral ischemia is an important source of damage, we use multiple PCR technique in detection of free radical oxidation environment line 33 globins in C.elegans (Globin) expression the difference, in order to find a new drug to eliminate free radicals, provide a new treatment for cerebral ischemia.
Hemodilution by lowering hematocrit and blood viscosity to improve microcirculation and tissue oxygen, can inhibit brain injury induced by ischemia-reperfusion. To study the effects of hypervolemic hemodilution on cerebral ischemia reperfusion injury. We object to adult male SD rats, the preparation of the model of cerebral ischemic reperfusion injury. Saline for blood thinners, expansion of blood dilution on the rat model of reperfusion. In the meanwhile, normal saline were injected through the tail vein of 0.5,1.0,2.0ml of hypervolemic hemodilution. By 2, 3, three (TTC) 5- phenyl tetrazole staining and image analysis method to calculate TTC staining area and infarct volume. Show that with the increase of saline injection volume, cerebral infarction volume was decreased, 2.0ml saline was injected into the cerebral infarction volume was significantly lower than the control group. The expansion of the blood dilution significantly The reduction of cerebral ischemia reperfusion model cerebral infarction volume in rats has a protective effect on cerebral ischemia reperfusion injury in rats.
Neuroglobin (NGB) is a new found in the vertebrate nervous system specific expression of the globin family members carrying oxygen, the study found that cerebral ischemia can promote the expression of neuroglobin, brain damage and excessive expression of neuroglobin can inhibit ischemia induced. In order to study the effect of neuroglobin on cerebral ischemia reperfusion injury. We object to adult male SD rats, preparation of cerebral ischemia reperfusion injury model. Using NGB and TAT-NGB (fusion leader peptide NGB) on cerebral ischemia reperfusion rat model of reperfusion intervention. At the same time, through the tail vein were injected different concentrations of NGB and TAT-NGB solution. In 2, 3, three (TTC) 5- phenyl tetrazole staining and image analysis method to calculate TTC staining area and infarct volume. The results showed that the volume of cerebral infarction in rats injected with NGB and TAT-NGB solution relative to the control group decreased at the dose of NGB 24mg/ and TAT-NGB kg When the dose was 10mg/kg, the volume of cerebral infarction decreased significantly, indicating that NGB could reduce the volume of cerebral infarction in rats with cerebral ischemia-reperfusion and protect the brain injury induced by ischemia-reperfusion.
The pearl protein is present in almost all kinds of organisms oxygen binding protein, its common feature is to contain helical sandwich structure. There are 33 kinds of typical globins in C.elegans, the function of these proteins is not clear. In order to study the relationship between 33 kinds of nematode globin and active oxygen free radicals. We used N2 wild nematodes as the experimental object, raised in containing different concentrations (0.3 mmol/L, 0.4 mmol/L, 0.5 mmol/L) of paraquat (PQ) medium nematode (NGM), five days later, the total RNA extraction of nematodes, reverse transcription was then amplified by multiplex PCR. 33 species of nematode globin, calculate the integral light the density of each band by gel quantitative analysis software, calculated the relative expression of each globin. Compared with the control group, the expression obtained 33 globin. The results showed that the increase of gene expression under PQ treatment: Globin-7, Globin -12, Globin -19, Globin -22, Globin -24, Globin -31. have significantly higher expression levels under PQ pressure. These proteins have potential to inhibit oxidative damage induced by PQ.

【学位授予单位】：西北农林科技大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：R363

【参考文献】