Diabetes is associated with posttranslational modifications in plasminogen resulting in reduced plasmin generation and enzyme-specific activity
Diabetes is associated with posttranslational modifications in plasminogen resulting in reduced plasmin generation and enzyme-specific activity
复制标题
DOI：
10.1182/blood-2013-04-494641
复制
发表时间：
2013-07-04
期刊：
影响因子：
20.3
通讯作者：
Grant, Peter J.
中科院分区：
文献类型：
--
作者：
Ajjan, Ramzi A.;Gamlen, Toby;Grant, Peter J.
糖尿病与纤溶功能减退有关，其机制仅部分了解。我们研究了体内纤溶酶原糖化对纤维蛋白溶解、纤溶酶生成、蛋白质水解活性和纤溶酶原-纤维蛋白相互作用的影响。血浆收集自健康对照组和1型糖尿病患者在改善胰岛素抵抗前后。通过显色法、浊度法和纤溶酶转化试验评价血浆纯化的纤溶酶（原）功能活性，并采用表面等离子体共振法测定纤维蛋白-纤溶酶原相互作用。纤溶酶原翻译后修饰通过质谱法定量，糖化位点通过肽图谱定位。糖尿病与受损的血浆纤维蛋白网络溶解有关，其在改善糖尿病后部分正常化。与对照组相比，糖尿病患者的纯化纤溶酶（原）的纤溶活性受损（分别为723 +/- 16和317 +/- 4 s; P <0.01），主要与纤维蛋白依赖性纤溶酶生成减少和蛋白酶活性降低有关（K-cat/K-M分别为2.57 +/- 1.02 x 10（-3）和5.67 +/- 0.98 x 10（-3）M-1 s（-1）; P < .05）。与对照组相比，糖尿病患者纤溶酶原上的N ε-果糖基-赖氨酸残基增加（分别为6.26 +/- 3.43和1.82 +/- 0.95%mol; P <0.01），赖氨酸107和557优先糖化，分别涉及纤维蛋白结合和纤溶酶（原）切割。糖尿病中纤溶酶原的糖化通过减少纤溶酶生成和降低蛋白质特异性活性直接影响纤溶，这些变化在血糖控制适度改善时是可逆的。
Diabetes is associated with hypofibrinolysis by mechanisms that are only partially understood. We investigated the effects of in vivo plasminogen glycation on fibrinolysis, plasmin generation, protein proteolytic activity, and plasminogen-fibrin interactions. Plasma was collected from healthy controls and individuals with type 1 diabetes before and after improving glycemia. Plasma-purified plasmin(ogen) functional activity was evaluated by chromogenic, turbidimetric, and plasmin conversion assays, with surface plasmon resonance employed for fibrin-plasminogen interactions. Plasminogen post-translational modifications were quantified by mass spectrometry and glycation sites located by peptide mapping. Diabetes was associated with impaired plasma fibrin network lysis, which partly normalized upon improving glycaemia. Purified plasmin (ogen) from diabetic subjects had impaired fibrinolytic activity compared with controls (723 +/- 16 and 317 +/- 4 s, respectively; P < .01), mainly related to decreased fibrin-dependent plasmin generation and reduced protease activity (K-cat/K-M 2.57 +/- 1.02 x 10(-3) and 5.67 +/- 0.98 x 10(-3) M-1 s(-1), respectively; P < .05). N epsilon-fructosyl-lysine residue on plasminogen was increased in diabetes compared with controls (6.26 +/- 3.43 and 1.82 +/- 0.95%mol, respectively; P < .01) with preferential glycation of lysines 107 and 557, sites involved in fibrin binding and plasmin(ogen) cleavage, respectively. Glycation of plasminogen in diabetes directly affects fibrinolysis by decreasing plasmin generation and reducing protein-specific activity, changes that are reversible with modest improvement in glycemic control.