DJ-1基因及其与帕金森病关系的研究进展

帕金森病是目前世界上最常见的神经系统退行性病变之一,DJ-1基因是一个与帕金森病相关的基因,其致病机制还不完全清楚.很多研究人员对DJ-1蛋白的功能进行了研究,目前已经发现DJ-1蛋白具有抗氧化、调节转录、参与能量代谢、抑制细胞凋亡等作用,本文总结了DJ-1基因的结构、突变形式、生物学作用及其与帕金森病发生的关系,以及DJ-1基因与其他导致帕金森病的基因之间的相互作用.对研究和了解帕金森病及其基因治疗具有重要意义.     

DJ-1基因多态性与四川地区散发性帕金森病的相关性研究

目的 了解DJ-1基因3个多态位点(g.168-185del;SNP405,refSNPID:rs3766606;293G/A)的频率以及与帕金森病的相关性.方法 采用病例-对照研究,应用聚合酶链反应-限制性片段长度多态性及DNA测序等技术对192例帕金森病患者和198名对照者的3个位点进行基因型的检测.结果 在g.168-185del位点,研究人群中Ins/Ins基因型较普遍,等位基因Del的频率很低(0.38%);在所检测的人群中未发现293G/A的多态性.上述结果与欧美国家的报道不一致.在SNP405 G/T多态位点中,在发病年龄小于40岁的帕金森患者群中G/T基因型频率显著高于对照组(18.75%vs5.54%,P=0.004,OR=6.30,95%CI:1.96～20.18).结论 g.168-185del和293G/A两多态性位点的频率在中国人群与欧美人群间可能存在差异;非翻译区SNP405 G/T多态性可能增加早发帕金森病的发病风险.     

DJ-1基因与帕金森氏病的研究进展

[摘要] 帕金森氏病是目前世界上最常见的神经系统退行性病变之一，DJ-1是一个与帕金森氏病相关的基因，其致病的作用机制不完全清楚。很多研究人员对DJ-1的蛋白功能进行了研究，目前已经发现DJ-1蛋白具有抗氧化、调节转录、参与能量代谢、抑制细胞凋亡等作用，本文总结了DJ-1的结构、突变形式、生物学作用与帕金森病发生的关系，以及DJ-1基因与其它导致帕金森氏病的基因之间的相互作用。对研究和了解帕金森氏病及其基因治疗具有重要意义。     

DJ-1在帕金森病和肿瘤中抗氧化作用的研究进展

氧化应激在帕金森病多巴胺能神经元变性中起着重要作用,活性氧(reactive oxygen species,ROS)产生的来源和机制包括多巴胺本身的代谢,线粒体功能障碍等。DJ-1在帕金森病和心力衰竭中起抗氧化作用,参与氧化应激保护细胞。DJ-1是癌症相关蛋白,它参与细胞内不同的信号通路。DJ-1可以调控氧化应激反应,对肿瘤细胞的侵袭转移行为产生了明确的影响,因此可以推测, DJ-1作为一种抗氧化剂可以影响肿瘤的治疗和复发。现在已证实DJ-1与癌症之间有着密切关系,但是它是如何作用的而改变细胞存活的信号通路的详细机制仍然未知。本文综述DJ-1在帕金森病,心衰,肿瘤中抗氧化机制,以及该靶点在肿瘤治疗中的研究进展。     

NURR1基因多态性与帕金森病的关联研究

目的 了解NURR1基因多态性与四川地区散发性帕金森病之间的相关性.方法 采用病例-对照研究,应用聚合酶链反应、等位基因特异性、限制性片段长度多态性对四川地区汉族人群241例帕金森病患者和236名正常对照NURR1基冈启动子区的c.-2922(C)2-3及第6内含子的ⅣS6+18imG多态位点进行关联分析.结果 IVS6+18insG位点帕金森病组3G/3G,3G/2G,2G/2G基因型频率与对照组相比差异无统计学意义(X2=3.733,P=0.155).进一步按发病年龄分层后发现,50岁以前发病的帕金森病患者基因型频率与对照组之间差异有统计学意义(X2=6.545,P=0.038).发病年龄＜50岁的帕金森病组患者3G/2G基因型频率显著高于对照组(54.12%vs 38.14%),并且与其他两组基因型合并相比差异有统计学意义(X2=6.537,P=0.011;OR=1.913,95%CI:1.159～3.158).c.-2922(C)2-3位点帕金森病组与对照组相比3C/3C,3C/2C及2C/2C基因型频率差异无统计学意义(P=0.766).结论 本研究结果提示NURR1基因ⅣS6+18insG多态可能与本组人群早发性帕金森病的遗传易感性相关;未发现c.-2922(C)2-3位点多态性与本组人群帕金森病的遗传易感性相关.     

慢病毒载体介导下DJ-1过表达细胞模型的建立

目的构建人野生型DJ-1及其L166P突变体的慢病毒载体并探讨慢病毒载体在构建基因过表达细胞模型中的作用。方法分别构建野生型DJ-1与L166P突变型DJ-1慢病毒载体质粒。进行测序确定比对正确后,进行质粒的大量扩增与制备并转染包装细胞系HEK293T细胞,荧光法和Western blot检测野生型DJ-1与L166P突变型DJ-1在细胞系中的表达。在确定目的蛋白正确表达之后,大量转染HEK293T细胞进行包装并生产携带目的基因的慢病毒颗粒。测定病毒上清滴度后感染PC12细胞,荧光显微镜和Western blot观察GFP荧光强度以及目的蛋白的表达,确定病毒的感染效率。结果成功构建携带DJ-1野生型及其突变体的慢病毒载体。该病毒载体可以转染进入HEK293T细胞内且目的蛋白能够正确表达。LV-DJ-1与LV-DJ-1/L166P的病毒滴度分别为2×10~9TU/m L与2×10~8TU/m L。病毒上清可以高效感染PC12细胞,绝大多数细胞可表达目的蛋白。外源野生型DJ-1和L166P突变体的蛋白表达量分别是内源性含量的315%和285%。结论慢病毒感染细胞效率很高,是很好的制备基因过表达细胞的方法。通过慢病毒载体介导,本研究获得了DJ-1及其突变体的过表达细胞模型。该模型可以用于后续DJ-1功能研究。     

DJ-1在肿瘤中作用的研究进展

DJ-1基因是一种新的线粒体依赖癌基因。当前在帕金森病领域,对DJ-1基因的研究较多,认为其与人类家族性早发型帕金森病相关。近来研究发现DJ-1基因与人类多种恶性肿瘤的发生、进展及预后等密切相关,可作为癌症发生的预警标志物,但也有DJ-1在肿瘤中低表达的报道。     

DJ-1蛋白在缺血性中风发病中的作用研究进展

人帕金森病蛋白7/DJ-1蛋白(PARK7/DJ-1)为帕金森病相关蛋白,近年来研究发现其可通过调节细胞内线粒体转位和自噬、利用细胞外旁分泌或自分泌方式保护缺血神经元、介导Nrf2/ARE通路上调谷胱甘肽、调节PTEN/PI3K/AKT信号通路调节缺血再灌注(IR)损伤,从而保护缺血后脑组织,有望成为缺血性卒中新的生物标志物及治疗靶点。本文从DJ-1蛋白概况、DJ-1蛋白在缺血性中风发病中的作用等方面对近年来DJ-1蛋白在缺血性中风发病中的研究进展进行归纳总结,并分析其作为缺血性卒中治疗靶点的优势及目前研究中存在的不足。     

DJ-1缺失增加出生前脂多糖暴露引起的出生后小鼠多巴胺能神经元丢失(英文)

目的:观察DJ-1缺失和出生前脂多糖(lipopolysaccharide,LPS)暴露对出生后小鼠多巴胺能(dopam-inergic,DA)系统和神经炎症的影响。方法:妊娠第10.5 d DJ-1基因敲除的小鼠腹腔注射脂多糖(10,000 EU/kg体重)后自然分娩的后代在4月和14月龄时处死。免疫组织化学染色结合体视学计数定量黑质酪氨酸羟化酶(Tyrosine hydroxylase,TH)和CD11b阳性细胞数量。高效液相色谱法测定纹状体DA代谢物水平。免疫荧光法测定TNF-α和IL-1β蛋白水平。结果:4月和14月龄的DJ-1基因敲除的小鼠均没有明显的DA神经元减少和脑内神经炎症改变。出生前接触过LPS的4月和14月龄野生型小鼠,黑质DA能神经元分别减少13.6%和23.1%,纹状体DA含量分别减少19.0%和26.2%,同时神经炎症改变明显。出生前接触过LPS的4月和14月龄DJ-1基因敲除小鼠,黑质DA能神经元分别减少22.5%和35.4%,纹状体DA含量分别减少34.3%和39.3%,同时脑内炎症反应更明显。结论:以上结果提示遗传因素缺失和环境因素可能共同引发帕金森病发生,进一步验证了帕金森病多因素损伤引发的发病假说。     

MicroRNA在建立DJ-1基因敲减细胞模型中的应用

 目的 与传统的siRNA方法建立基因敲减模型不同,探讨合成microRNA(miRNA)在DJ-1基因敲减细胞模型中的应用。方法 构建针对DJ-1基因的合成miRNA载体,合成DJ-1基因的siRNA干扰片断。在脂质体介导下,将上述两种小干扰RNA载体或片断分别转染MN9D细胞系,应用real-time PCR和Western blots检测目的基因DJ-1的mRNA和蛋白表达。结果 与Control组相比,转染合成microRNA的MN9D细胞中,DJ-1的mRNA水平下调90%（p<0.05）,蛋白水平下调70%~85%(p<0.05);而转染siRNA的MN9D细胞中,DJ-1的mRNA水平下调50%~70%（p<0.05）,蛋白水平下调20%~50%（p<0.05）。结论 microRNA与siRNA均可作为基因敲减的重要研究手段。与传统的siRNA相比,合成microRNA对目的DJ-1的干扰效率更为显著。     

Preparation and application of monoclonal antibodies against oxidized DJ-1. Significant elevation of oxidized DJ-1 in erythrocytes of early-stage Parkinson disease patients

DJ-1 was initially identified as a novel oncogene and has recently been found to be a causative gene for a familial form of Parkinson's disease (PD), viz, PARK7. Cysteine residue at position 106 (Cys-106) in DJ-1 was found to be oxidized preferentially under oxidative stress. In the present study, we developed specific antibodies against Cys-106-oxidized DJ-1 using baculovirus particles displaying the surface glycoprotein gp64-fusion protein as the immunizing agent. Western blot analysis combined with two-dimensional gel electrophoresis revealed that these antibodies specifically recognized oxidized DJ-1. Furthermore, we developed a competitive enzyme-linked immunosorbent assay (ELISA) for detecting oxidized DJ-1 and measured blood levels of oxidized DJ-1 in PD patients (n = 15). It was observed that the levels of oxidized DJ-1 in erythrocytes of unmedicated PD patients were markedly higher without overlap than those of medicated PD patients and healthy subjects. No significant difference was observed in DJ-1 levels between mediated and unmediated PD patient. These results suggest the oxidative modification of DJ-1 in PD patients and the potential application of the antibody for diagnosis of PD at early-stage.     

Elevation of oxidized DJ-1 in the brain and erythrocytes of Parkinson disease model animals

DJ-1, the causative gene of a familial form of Parkinson's disease (PD), has been reported undergo oxidation preferentially at the 106th cysteine residue (Cys-106) under oxidative stress. Recently, it has been found that the levels of oxidized DJ-1 in erythrocytes of unmedicated PD patients are markedly higher than those in medicated PD patients and healthy subjects. In the present study, we examined the changes in oxidized DJ-1 levels in the brain and erythrocytes of PD animal models using specific antibodies against Cys-106-oxidized DJ-1. Treatment with PD model compounds such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 6-hydroxydopamine significantly elevated the levels of oxidized DJ-1 in erythrocytes. Immunohistochemical analysis also revealed that the number of oxidized DJ-1 antibody-positive cells in the substantia nigra of MPTP-treated mouse increased in a dose-dependent manner. These results suggest that the oxidative modification of DJ-1 in the brain and erythrocytes is involved in the pathogenesis of PD in animal models.     

Genetic study of Apolipoprotein E gene,alpha‐1 antichymotrypsin gene in sporadic Parkinson disease

Several lines of evidence have suggested some common genetic risk factors for Alzheimer disease (AD) and Parkinson disease (PD) because there are some overlapping pathologies in these two neurodegenerative diseases. In the present study, we investigated the role of Apolipoprotein E gene polymorphism and the signal peptide polymorphism in alpha‐1 antichymotrypsin (ACT) gene in idiopathic sporadic PD. The study was performed in a sample consisting of 68 PD cases and 160 healthy subjects in Shanghai China. We found no significant differences of ACT gene polymorphic distribution between PD cases and controls. The ApoE gene ε2/ε4 genotype was significantly more frequent in PD subjects (χ² = 7.126, df = 1, P = 0.008) and conferred a 12.70 times susceptibility for PD (OR = 12.62, 95% CI: 1.445–110.17, χ² = 5.259, P < 0.05, AF = 4.59%). No interaction of ApoE and ACT genes was detected in PD. Therefore, our data suggested that the ApoE ε2/ε4 genotype might be a susceptibility variant of moderate effect for sporadic idiopathic PD in our samples, whereas the ACT gene signal peptide polymorphism might not. © 2002 Wiley‐Liss, Inc.     

Significance and confounders of peripheral DJ-1 and alpha-synuclein in Parkinson's disease

DJ-1 and α-synuclein are leading biomarkers for Parkinson's disease diagnosis and/or monitoring disease progression. A few recent investigations have determined DJ-1 and α-synuclein levels in plasma or serum, a more convenient sample source than cerebrospinal fluid; but the results were variable or even contradictory. Besides limitations in detection technology and limited number of cases in some studies, inadequate control of several important confounders likely has contributed to these inconsistent results. In this study, the relative contribution of each blood component to blood DJ-1 and α-synuclein was evaluated, followed by quantification of plasma levels of both markers in a larger cohort of patients/subjects (∼300 cases) whose cerebrospinal fluid DJ-1 and α-synuclein levels have been determined recently. The results demonstrated that the DJ-1 and α-synuclein in blood resided predominantly in red blood cells (>95%), followed by platelets (1–4%), white blood cells and plasma (≤1%), indicating that variations in hemolysis and/or platelet contamination could have a significant effect on plasma/serum DJ-1 and α-synuclein levels. Nonetheless, after adjusting for the age, although there was a trend of decrease in DJ-1 and α-synuclein in patients with Parkinson's or Alzheimer's disease compared with healthy controls, no statistical difference was observed in this cohort between any groups, even when the extent of hemolysis and platelet contamination were controlled for. Additionally, no correlation between DJ-1 or α-synuclein and Parkinson's disease severity was identified. In conclusion, unlike in cerebrospinal fluid, total DJ-1 or α-synuclein in plasma alone is not useful as biomarkers for Parkinson's disease diagnosis or progression/severity.     

LINGO1 rs9652490 variant in Parkinson disease patients

Essential tremor (ET) has been hypothesized to be a risk factor for the development of Parkinson disease (PD). Recently, rs9652490 variant in the leucine-rich repeat and Ig domain containing 1 gene (LINGO1) was found to be associated with ET susceptibility. To evaluate whether the same variant is associated also with PD susceptibility, we investigated the association between the LINGO1 rs9652490 variant and PD phenotype in Caucasian and Chinese PD subjects. We found no significant differences in genotypic and allele distribution between patients and control subjects (χ(2)=1.931, p=0.381 for genotypic distribution; χ(2)=0.001, p=0.973 for allele distribution), suggesting this variant is not associated with PD.