【作者】 于飞；

【导师】 姚华；

【作者基本信息】 新疆医科大学 ， 劳动卫生学与环境卫生学， 2013， 博士

【摘要】 国内外大量流行病学研究表明，随着人们生活水平的提高，高尿酸血症的发病率日渐增高。高尿酸血症（hyperuricemia，HUA）除了引发痛风和尿酸性肾病等疾病，还可引起胰岛素抵抗，加速血管病变和糖耐量异常的发生和发展，与高血压、动脉粥样硬化、冠心病、血脂血糖代谢紊乱、肥胖和胰岛素抵抗等代谢综合症疾病密切相关。因此加强对高尿酸血症的认识和研究，积极探寻其发病机制，阻断高尿酸血症向相关疾病转化，寻找有效的防治策略和措施，显得非常必要和迫切。蛋白质作为基因功能和生理功能的实施者和生命现象的直接体现者，对蛋白质结构和功能的研究将直接阐明生命在生理或病理条件下的变化机制。近些年兴起的蛋白质组学研究方法为标准蛋白的筛选提供了有力工具，从而为研究重大疾病病理生理学机制、发现早期诊断的特异性标志物、研发药物作用靶点等开辟了新的途径。本课题选择维吾尔族及汉族高尿酸血症人群做为研究对象，运用双向电泳和串联质谱联用的研究方法进行研究，不仅可以发现不同民族高尿酸血症患者潜在的差异蛋白质，探讨可能参与不同民族高尿酸血症发病机制的蛋白质，而且能为将来进一步研究生活环境因素改变和遗传因素交互作用对高尿酸血症发病的综合影响奠定基础，为相关代谢性疾病的人群防治提供科学建议。目的：（1）应用2-D电泳技术检测维吾尔族和汉族原发性高尿酸血症患者和健康人血清蛋白质斑点，初步筛选出两个民族的患者和健康人的血清差异蛋白质。（2）应用基质辅助激光解吸飞行时间串联质谱（MALDI-TOF-MS/MS）技术鉴定差异蛋白质，筛选出可能参与了高尿酸血症的发生和发展的蛋白质，探讨不同民族高尿酸血症发病的可能机制。方法：（1）临床资料及血清标本采集：按照纳入、排出标准收集汉族、维吾尔族原发性高尿酸血症患者血清各15例为病例组；选择同期就诊的年龄、性别、地域等相匹配的汉族、维吾尔族健康体检者血清各15例为正常对照组。每组按等体积方式混合为一个血清样本。血清都是在患者和健康志愿者知情的情况下收集，所有处理过程都符合新疆医科大学第一附属医院医学伦理委员会的要求。（2）双向电泳：利用亲和捕获的方法去除血清混合样本中高丰度的白蛋白和免疫球蛋白，并除去血清中存在的影响后续实验的组份，然后用双向电泳方法进行蛋白质的分离。分离获得的凝胶内的蛋白点通过胶内考马斯亮蓝染色法显色，利用图像分析软件，经定量比较筛选出在维吾尔族和汉族高尿酸血症患者和健康人血清双向电泳图谱中表达存在显著差异的蛋白斑点。为了保证实验结果的重复性，以上实验在相同条件、不同时间下重复进行3次。（3）蛋白质点鉴定：双向电泳获得的凝胶中的差异蛋白斑点经切胶、酶解后运用基质辅助激光解吸飞行时间串联质谱技术（MALDI-TOF-MS/MS）进行鉴定，获得差异蛋白点的质量指纹图（PMF）和肽序列标签图（PST）及相关数据。（4）质谱数据的检索：将PMF数据和PST数据在NCBI（nr）非冗余数据库和Swissprot数据库进行检索。在两个数据库中检索数据一致并且Total Ion Score C.I.%大于95%的认为是成功鉴定出的蛋白质。（5）差异蛋白质的验证：本研究另外分别收集了维吾尔族和汉族原发性高尿酸血症患者血清各30例及维吾尔族和汉族健康人的血清各30例，用Western-blot方法验证补体C3和触珠蛋白在各组中的表达情况，同时评价差异表达蛋白质在高尿酸血症患者血清中表达的相对特异性并且探讨其与高尿酸血症的关系。结果：（1）获得了重复性较好的血清蛋白质组双向凝胶电泳图谱：血清标本经过预处理后，进行了3次重复双向电泳，获得了重复性较好的电泳图谱。维吾尔族和汉族血清双向电泳图谱中约各检测到650个蛋白质斑点。这些蛋白斑点经定量比较，维吾尔族高尿酸血症患者血清中筛选出10个蛋白斑点与健康人血清表达存在差异，其中9个蛋白斑点在高尿酸血症患者血清中表达上调，1个蛋白斑点在高尿酸血症患者血清中表达下调；汉族高尿酸血症患者血清中筛选出8个蛋白斑点与健康人血清表达存在差异，其中4个蛋白斑点在高尿酸血症患者血清中表达上调，4个蛋白斑点在高尿酸血症患者血清中表达下调；（2）差异蛋白斑点的质谱鉴定及数据库搜索：所有差异蛋白斑点经MALDI-TOF-MS/MS质谱分析和数据库检索，维吾尔族及汉族高尿酸血症组各成功鉴定出4种蛋白质。汉族高尿酸血症组鉴定出的4种蛋白质分别是补体C3（C3）、触珠蛋白（Hp）、α1-抗胰蛋白酶（α1-AT）和载脂蛋白L1（APOL1），其中补体C3、Hp、α1-AT呈上调表达，APOL1呈下调表达；维吾尔族高尿酸血症组鉴定出的的4种蛋白分别是补体C3（C3）、触珠蛋白（Hp）、补体C4（C4）和载脂蛋白A1（APOA1），均呈上调表达；（3）补体C3和Hp的Westem-blot验证：对在汉族和维吾尔族高尿酸血症患者血清中均呈上调表达的补体C3和触珠蛋白用免疫印迹法（Western blot）进行验证，同时评价两种蛋白在高尿酸血症患者血清中表达的相对特异性。结果显示，触珠蛋白和补体C3在维吾尔族和汉族高尿酸血症患者及健康人群血清中都有表达，但在高尿酸血症患者血清中的表达高于健康人，差异有统计学意义（P＜0.05）。结论：本研究进一步证实了蛋白质组学技术是研究疾病差异蛋白质的有力工具。通过双向电泳联合质谱的方法，我们发现补体C3（C3）、触珠蛋白（Hp）、α1-抗胰蛋白酶（α1-AT）在汉族高尿酸血症患者血清中表达上调，载脂蛋白L1（APOL1）在汉族高尿酸血症患者血清中表达下调；补体C3（C3）、触珠蛋白（Hp）、补体C4（C4）和载脂蛋白A1（APOA1）在维吾尔族高尿酸血症患者血清中均表达上调。这些差异表达蛋白质可能参与了高尿酸血症的发生和发展以及高尿酸血症与其他代谢综合症疾病之间的相互影响。更多还原

【Abstract】 The large number of domestic and international epidemiological studies have shownthat the incidence of hyperuricemia (HUA) increase gradually with the improvement ofpeople’s living standards. HUA not only leads to gout and uric acid kidney diseases, butalso can cause insulin resistance, vascular lesions and glucose tolerance abnormal.There isclosely correlationship between HUA and metabolic syndrome (hypertention, arteryatherosclerosis, coronary heart disease, dyslipidemia, obesity and insulin resistance).Therefore it is very necessary and urgent to strengthen the study of hyperuricemia and toexplore its pathogenesis, prevent transforming to related diseases.The proteomics methodsbooming in recent years provide a powerful tool for the screening of a standard protein.In this study we have used proteomics to identify differentially expressed proteins ofUyghur and Han patients with HUA in comparison to normal subjects’serum.The validityof the differential protein expression in patient’s with HUA was further examined andconfirmed with Western-blot.From this study we want to found that the differentlyexpressed proteins in Uyghur and Han patients with HUA, to explore the proteins possiblyinvolve in the pathogenesis of hyperuricemia.And for applying the foundation for furtherstudying of interaction of environment factors and genetic factors on hyperuricemia.Objective:(1) Screen the differently expressed proteins in Uyghur and Han patients with HUAand normal population by2-DE.(2) Identify the differently expressed proteins by MALDI-TOF-MS/MS, select theproteins that possibly involve in the pathogenesis of HUA and transformation betweenHUA and metabolic diseases. Methods:(1) Collection for clinical data and serum samples15sera of Uyghur and Han patients with HUA were selected respectively as studygroups and the control groups were selected from health examination people in the FirstAffiliated Hospital.Blood sample was taken from fasting patients in the morning.Sera wasseparated and freezed.The serum is collected in the case of informed patients and healthyvolunteers, and all process meet the requirements of the Ethics Committee of the FirstAffiliated Hospital of Xinjiang Medical University(2) Two dimensional electrophoresis (2-DE)Total protein was extracted, purified and quantified, and then separated by2-DE.Different protein spots were stained by Coomassie Brilliant Blue, and the twodimentional electrophoregram was analyzed with the application of PDQuest7.3.0software to screen the different proteins.In order to ensure the reproducibility of theexperimental results, the above experiment was repeated three times under the sameconditions, different time.(3) Identification of proteins by MALDI-TOF–MS/MSprotein spots which displayed significant expressional differences (up-ordown-regulated by more than2.5times) were excised from the gel and sliced into sectionsabout1mm3.Samples were analyzed using MALDI-TOF-MS/MS.After MS analysis,peptides, which were different from matrix PMF (peptide mass fingerprint), were selectedand MS/MS (massspectrum/massspectrum) was achieved.(4) Database retrieval.The mass spectrum obtained from MALDI-TOF was searched using Mascotsoftware from NCBInr (www.matrixscience.com) and Swissprothttp (www.expasy.ch/sprot). The results were accordance in the two database and Total Ion Score C.I.%wasover95%were recogonized as successfully identified proteins.(5) Validation of differential expressed proteins.The levels of the proteins identified above (associated with HUA pathology) weremeasured in blood serum samples using Western-blot.Blood serums were obtainedrespectively from another30patients with HUA in Uyghur and Han and30normalsubjects in Uyghur and Han.Results:(1)2-D maps with a good reproducibility were obtained. After pretreatment, about650protein spots were respectively detected in2-dimensional electrophoresis profiles of Han and Uygur sera.By the quantitative analyse,there were8differential expressed protein spots in Han patients with HUA and10differential expressed protein spots in Uygur patients with HUA compared to controlgroups. Four of the total8proteins were up-expressed and other four proteins weredown-expressed.And nine of the total10proteins were up-expressed and other one proteinwas down-expressed in the serum.(2) Identification and verification of protein spots8PMFs were successfully identified by MALDI-TOF-MS/MS analyzing andretrieving NCBInr and Swissspot database.Complement3, haptoglobin, α1-antitrypsinwere up-regulated and apolipoprotein L1was down-regulated in Han patients as comparedwith control group. Complement3, complement4, haptoglobin, apolipoprotein A1wereup-regulated in Uygur patients as compared with control group.(3) Validation of complement3and haptoglobin by Western-blotComplement3and haptoglobin were validated by Western-blot and the results ofWestern-blot support the results of proteomic analysis.Conclusions:This study further validated that the proteomics techniques are powerful tools forscreening different proteins from patient’s serum.Our results revealed a significantlyincreased expression of Hp, C3and α1-AT in Han patients with HUA, and a significantlylowered level of APO L1in Han patients with HUA. And Complement3, complement4,haptoglobin, apolipoprotein A1are in higher level expression in Uygur patients’ sera thanin control.These proteins are correlated with immunization and lipid metabolism..Ourresults of comparative serum proteomics analysis might provide clues for furtherelucidating the role of these proteins in HUA. These differentially expressed proteins maybe involved in the HUA occurrence, development and the relationship betweenhyperuricemia and other metabolic syndrome diseases.更多还原