Mechanism of arterial calcification: Role of matrix metalloproteinases

动脉钙化的机制：基质金属蛋白酶的作用

• 批准号: 16390351
• 负责人: SASAJIMA Tadahiro
• 金额: $ 8.83万
• 依托单位: Asahikawa Medical College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16390351/
• 关键词: arterial calcification; matrix metalloprotainases; medial calcification; diabetes; dialysis; osteocalcin; vein graft; electroprobe microanalysis; マトリックスメタロポロテイナーゼ; 電子線プローブマイクロアナライザー; AGE; 動脈硬化

OBJECTIVES: Current increase of patients with diabetes/dialysis increases opportunities of management of ischemic diseases with calcified arteries. In the present study, we investigated the mechanism of arterial calcification in diabetic/dialysis patients as well as animal model, and a role of matrix metalloproteinases in arterial calcification.MATERIAL AND METHOD : During the study period, human vein graft specimens were obtained from 12 patients with diabetes/dialysis who underwent revised surgery for vein graft stenosis 3-10 months after the initial vein bypasses for limb ischemia, and animal aortic specimens were obtained from old diabetic rats (Otsuka Long Evans Tokushima Fatty rat; OLETF rat) with age of 40 weeks, and were stored in cell baner for later analysis. All of the specimens were cross-sectioned, and calcification microspots were screened by light microscopy and SEM; when calcified microspots were identified by SEM, the specimens were analyzed by the electroprobe microan … More alysis (EPMA) for confirmation of calcification, and were also subjected to immunohistochemistry. In immunohistochemistry, osteocalcin and MMC-3,-9, and-13 were examined. After the confirmation, the calcification spots was subjected to TEM to evaluate relation to the surrounding tissue.RESULTS : The SEM demonstrated many various sized microspots in the media in all human vein grafts as well as rat aortas, and EPMA demonstrated the presense of phosphorus and calcium in the spots, probing the microspots to be calcification. In human vein grafts in diabetic/ dialysis patients, microcalcification initiates within 3 months after implantation.Immunohistochemistry demonstrated the expression of MMPs as well as osteocalcin, but the detail relationship to the initiation mechanism of arterial calcification remained unclear. TEM showed calcification spots were with diameters of 70-300 nm, and located in extracellular matrix. Further magnification disclosed the calcification consisted of an aggreigation of nanoparticles with a diameter of 10nm.CONCLUSION : Arterial calcification develops extracellular matrix in media, and forms aggregation with a diameter of 10 nm particles. Relation between development of calcification and gene expressions such as MMPs and osteocalcin still remained unclear. Less

优点：目前糖尿病/透析患者的增加了管理动脉钙化缺血性疾病的机会。在本研究中，我们研究了糖尿病/透析患者和动物模型动脉钙化的机制，以及基质金属蛋白酶在动脉钙化中的作用。材料和方法：在研究期间，从12名患有糖尿病/透析的患者获得人静脉移植物样本，这些患者在最初的静脉旁路术治疗肢体缺血后3-10个月接受了静脉移植物狭窄的修正手术，从40周龄的老年糖尿病大鼠（Otsuka Long Evans德岛脂肪大鼠; OLETF大鼠）获得动物主动脉标本，并储存在细胞库中用于以后的分析。对所有标本进行横切，光镜和扫描电镜下筛选钙化微斑，扫描电镜下识别钙化微斑后，用电探针显微镜分析标本。 ...更多信息 用电子探针分析（EPMA）确认钙化，并进行免疫组化。免疫组化检测骨钙素和MMC-3、-9和-13。结果：扫描电镜（SEM）显示所有人移植静脉及大鼠动脉中膜内均存在大小不一的钙化点，电子探针（EPMA）显示钙化点内含有磷、钙元素，提示钙化点与周围组织的关系。在糖尿病/透析患者的人静脉移植物中，微钙化在植入后3个月内开始，免疫组织化学显示MMPs和骨钙素的表达，但与动脉钙化起始机制的详细关系尚不清楚。电镜下可见钙化斑，直径70-300 nm，位于细胞外基质中。结论：动脉钙化中膜内有细胞外基质生成，形成直径约10 nm的颗粒聚集体。钙化的发生与MMPs和骨钙素等基因表达的关系尚不清楚。少