Ratel David, Glazier Geneviève, Provençal Mathieu, Boivin Dominique, Beaulieu Edith, Gingras Denis, Béliveau Richard
Laboratoire de Médecine Moléculaire Ste-Justine-UQAM, Centre de Cancérologie Charles-Bruneau, Hôpital Ste-Justine et Université du Québec à Montréal, 3175 Chemin Côte-Ste-Catherine, Montréal, QC, Canada H3T 1C5.
Thromb Res. 2005;115(1-2):143-52. doi: 10.1016/j.thromres.2004.07.008.
Fibrinogen and fibrin are molecules with overlapping roles in blood clotting, fibrinolysis, wound healing, inflammation, matrix and cellular interactions and neoplasia. There is currently much interest in the possible use of fibrinolytic agents in human therapeutics. In this study, we report the presence of fibrinolytic activities in shark cartilage extract (SCE). In vitro, SCE at 100 microg/ml completely degraded fibrin gel in an aprotinin-insensitive manner, suggesting a non-plasmin molecular nature. SCE was able to cleave all chains of fibrinogen and fibrin and the cleavage was completely inhibited by 1,10-phenanthroline, suggesting an essential role for metalloprotease(s) in this process. Using fibrinogen zymography, we show that SCE contains two plasmin-independent fibrinolytic activities and that these activities are correlated with the presence of 58 and 62 kDa proteases in the extract. SCE-fibrinolytic activities are inhibited by dithiothreitol, suggesting that disulfide bonds are necessary for the protease structure. Finally, using thromboelastography, SCE markedly induced retraction of human platelet-rich plasma (PRP) clot, this process being completely abolished by 1,10-phenanthroline. These data suggest the presence of novel non-plasmin fibrinolytic activities within SCE. This extract may thus represent a potential source of new therapeutic molecules to prevent and treat vaso-occlusive and thromboembolic disorders.
纤维蛋白原和纤维蛋白是在血液凝固、纤维蛋白溶解、伤口愈合、炎症、基质与细胞相互作用以及肿瘤形成中发挥重叠作用的分子。目前人们对纤溶药物在人类治疗中的潜在用途兴趣浓厚。在本研究中，我们报告了鲨鱼软骨提取物（SCE）中存在纤溶活性。在体外，100微克/毫升的SCE以一种对抑肽酶不敏感的方式完全降解纤维蛋白凝胶，这表明其具有非纤溶酶的分子性质。SCE能够切割纤维蛋白原和纤维蛋白的所有链，并且这种切割被1,10 - 菲咯啉完全抑制，这表明金属蛋白酶在该过程中起关键作用。使用纤维蛋白原酶谱法，我们表明SCE含有两种不依赖纤溶酶的纤溶活性，并且这些活性与提取物中58 kDa和62 kDa蛋白酶的存在相关。SCE的纤溶活性被二硫苏糖醇抑制，这表明二硫键对于蛋白酶结构是必需的。最后，使用血栓弹力图，SCE显著诱导富含人血小板血浆（PRP）凝块的回缩，这一过程被1,10 - 菲咯啉完全消除。这些数据表明SCE中存在新型的非纤溶酶纤溶活性。因此，这种提取物可能代表了一种预防和治疗血管阻塞和血栓栓塞性疾病的新治疗分子的潜在来源。
