金属催化氧化作用对高级氧化蛋白产物生成的影响  

Effects of metal-catalyzed oxidation on the formation of advanced oxidation protein products

作　　者：李丽[1] 彭艾[1] 朱开元[1] 于宏[1] 李新华[1] 李昌斌[1] 

机构地区：[1]同济大学附属第十人民医院肾脏免疫科,上海200072

出　　处：《中华医学杂志》2008年第10期674-678,共5页National Medical Journal of China

基　　金：国家自然科学基金资助项目（30472163）;上海市自然科学基金资助项目（06ZR14161）

摘　　要：目的探讨金属催化氧化（MCO）与高级氧化蛋白产物（AOPP）生成的关系及机制。方法血液样本采自健康人（n=3）和尿毒症患者（n=4）。AOPP采用紫外分光光度法测定，其波谱特点由高效凝胶色谱法分析。人血清白蛋白（HSA）组、健康人和尿毒症患者血浆蛋白与不同浓度的铜离子在有无过氧化氢存在下共同温育30min和24h。用AOPP水平、蛋白交联聚集、破碎、对羟自由基的清除能力衡量MCO对蛋白质的损伤程度。结果（1）与对照组（0mmol／L铜）相比，各组铜离子均以剂量相关的方式诱导AOPP的产生。特别是存在过氧化氢的情况下，铜离子诱导的HSA组AOPP水平增幅超过123％，差异有统计学意义（P〈0．05）。（2）单独过氧化氢的存在或加用铜离子并不能增强铜离子对各种蛋白的聚集作用，相反却诱导了更多的蛋白碎片。（3）除了HSA组外，健康人或尿毒症患者组，与AOPP产生最为相关的蛋白碎片相对分子质量均为7100。（4）健康人组基础AOPP水平比尿毒症患者组低约2倍，清除羟自由基的能力要高出患者组1．38～9．03倍。结论金属铜离子／过氧化氢催化氧化作用参与了AOPP的形成；其诱导生成的蛋白碎片可能也是增加AOPP形成的机制之一。Objective To explore the relationship between metal-catalyzed oxidation （MCO） and the formation of advanced oxidation protein products （ AOPPs ）. Methods Specimens of human serum albumin （HSA） and pooled plasma were collected from 3 healthy volunteers and 4 uremia patients were divided into 3 groups ： Group A incubated with copper sulfate solution of the concentrations of 0, 0.2, or 0.5 mmol/L, Group B, incubated with hydrogen peroxide 2 mmol/L, and Group C, incubated with copper sulfate 0.2 or 0.5 mmol/L plus hydrogen peroxide 2 mmol/L. 30 min and 24 h later the AOPP level was determined by ultraviolet visible spectrophotometry. High-performance liquid chromatography （HPLC） was used to observe the fragmentation effect on plasma proteins. Ninhydrin method was used to examine the protein fragments. The scavenging capacity of hydroxyl radical by macromolecules was measured so as to estimate the extent of damage for proteins induced by MCO. Results （ 1 ） The AOPP level of the HSA and plasma specimens of the uremia patients increased along with the increase of cupric ion concentration in a dose-dependent manner, especially in the presence of hydrogen peroxide （P 〈 0.05 ）. （2） Aggregation of proteins was almost negligible in all groups, however, HPLC showed that cupric ion with or without hydrogen peroxide increased the fragments in the HAS specimens （with a relative molecular mass of 5000） and uremia patients＇ plasma proteins （with the molecular mass 7000）. （3） The plasma AOPP level of the healthy volunteers was 68. 2 μmol/L ± 2. 4 μmol/L, significantly lower than that of the uremia patients （158.5 μmol/L ±8.2 μmol/L）. 4） The scavenging ability to clear hydroxyl radical by plasma proteins of the healthy volunteers was 1.38 - 9.03 times as higher than that of the uremia patients. Conclusion MCO contributes to the formation of AOPPs mainly through its fragmentation effect to proteins.

关 键 词：氧化物 催化作用 色谱法 凝胶 

分 类 号：R686[医药卫生—骨科学]