李源德2006-07-262018-07-112006-07-262018-07-112005http://ntur.lib.ntu.edu.tw//handle/246246/23682本計畫延續第一年成果,持續自粥狀動脈硬化斑塊中萃取oxLDL ,或取自循 環血液中的LDL 經由FPLC 分離LDL 子類。這些來自不同狀態不同氧化程度的 LDL ,在經trypsin 消化之後,以MALDI-TOF 質譜儀來確定受氧化修飾的區域。然 因國人之粥狀硬化斑塊取得有困難度,特別是量的限制,通常要匯集許多病人的檢 體才得以進行分析。目前除了持續收集病人檢體,並尋求靈敏度較高功能較吻合需 求的質譜儀。本機構已陸續購入SELDI, MALDI-TOF, MALDI-QTOF, LC-QTOF 四 種不同功能的質譜儀,MALDI-TOF 鑑定出的蛋白質,可將它的抗體coating 於chip , 再用SLEDI 進行大量篩選,以作為臨床的應用;MALDI-QTOF 則可進行peptide 定 序;而LC-QTOF 則可以在奈米的等級下進行極微量的蛋白質後修飾位置之研究。 藉由這些先進設備的陸續設置完成,即可達成確認氧化修飾區域的既定目標。 此外,本年度亦著手研究oxLDL 對細胞功能性的調控影響,乃是藉由proteomic 方法研究體外銅氧化LDL 與血液分離出的LDL 對人類臍帶靜脈內皮細胞 (human umbilical vein endothelial cells, HUVEC) 蛋白質之調控,並比較兩種處理方式對 HUVEC 細胞蛋白質調控方式的異同。針對被調控的未知蛋白質以質譜儀加以鑑定,並將探討其與粥狀硬化形成之關聯性,作為未來研究的新方向。 步驟:HUVEC 與serum-free medium, 正常LDL ,銅氧化LDL (氧化2 或24 小 時) 及血液分離出的LDL (L1, L3, and L5) 培養24 小時後,監測MCP-1 產量以作為 細胞發炎的標準。同時將細胞蛋白質經二維電泳分析得protein profiles ,再以 MALDI-TOF 質譜儀鑑定蛋白質。 結果:不同濃度的24 小時氧化LDL 作用對HUVEC 細胞數與MCP-1 濃度並 沒有明顯的影響。HUVEC 與不同氧化程度的LDL 培養24 小時,細胞存活數與 MCP-1 產量並無變化。但經血液分離出的LDL 與HUVEC 作用24 小時則可發現 L5 的細胞數量較L1 與L3 少,而MCP-1 則較高,顯示L5 可以引起較強的免疫發 炎反應及具有較強的atherogenic 能力。初步結果顯示protein profiles 不盡相似,可 能是因為銅氧化LDL 及血液分離出的LDL 對HUVEC 調控的方式不同,不過仍有 待進一步的量化統計。經由質譜儀鑑定出有調控的蛋白質大多與氧化還原相關;以 peroxiredoxins 與heat shock proteins 為大宗。 經由proteomic 方法鑑定出的蛋白質,為探討粥狀動脈硬化的形成,提供了新 的研究方向。我們將針對特定蛋白質加以調控,以觀察它在粥狀硬化斑塊中扮演的 角色。The objective of this study was to study the protein profiles of HUVEC regulated by oxLDL and LDL circulating subfraction by proteomic approaches. In addition, the candidate proteins which were regulated by oxidized LDL and LDL subfractions were identified. Human umbilical vein endothelial cells (HUVECs) were incubated with serum-free medium, native LDL (100 ug/mL), oxLDL (2hr- and 24 hr-oxidized; 100 ug/mL), LDL circulating subfraction (L1, L3 and L5; 50 ug/mL) for 24 hrs, respectively. MCP-1 was measured as an indicator of inflammation. Cytosolic proteins were applied in 2D electrophoresis and identified by MALDI-TOF mass-spectrometer. No differences of cell viability and MCP-1 production were observed on dose responses of 24hr- oxLDL treatment. Various grades of copper oxidation of LDL had the same effects on MCP-1production and cell viability. Circulating subfraction L5 had a highest inflammatory reaction and caused lower cell viability, suggested that L5 had a higher atherogenic capability than L1 and L3 did. The protein profiles of oxLDL and LDL subfraction were different in the preliminary test. However, more replications and statistical analysis are required to make the conclusion. For those proteins had been identified at present, most of them were redox-related proteins, peroxiredoxins and heat shock proteins were the majority.application/pdf136395 bytesapplication/pdfzh-TW國立臺灣大學醫學院內科氧化性低密度脂蛋白之結構及其臨床應用研究(2/3)reporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/23682/1/932314B002031.pdf