Direct-acting fibrinolytic enzymes in shark cartilage extract: potential therapeutic role in vascular disorders.
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.
Ratel
David
D
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.
Glazier
Geneviève
G
Provençal
Mathieu
M
Boivin
Dominique
D
Beaulieu
Edith
E
Gingras
Denis
D
Béliveau
Richard
R
D000818:Animals; D002356:Cartilage / Q000201:enzymology*; D002457:Cell Extracts; D003018:Clot Retraction / Q000187:drug effects; D004220:Disulfides; D004798:Enzymes / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D005337:Fibrin / Q000378:metabolism; D005340:Fibrinogen / Q000378:metabolism; D005341:Fibrinolysin / Q000494:pharmacology; D005343:Fibrinolytic Agents / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D045726:Metalloproteases; D008970:Molecular Weight; D012754:Sharks; D014652:Vascular Diseases / Q000188:drug therapy
D002457:Cell Extracts; D004220:Disulfides; D004798:Enzymes; D005343:Fibrinolytic Agents; D005337:Fibrin; D005340:Fibrinogen; D045726:Metalloproteases; D005341:Fibrinolysin