Staphylokinase reduces plasmin formation by endogenous plasminogen activators.

• Hyperfibrinolysis is a consequence of imbalance between fibrinolytic activators and their inhibitors. Increased levels of circulating plasminogen (Plg) activators such as tissue- or urokinase-type plasminogen activators (tPA or uPA respectively) are the most common causes of hyperfibrinolysis, occasionally causing major hemorrhages. We found that staphylokinase (SAK), a well-known Plg activator of bacterial origin, inhibits Plg activation mediated by endogenous tPA and uPA. Furthermore, mixture of SAK with tPA led to a significantly reduced Plg-dependent fibrinolysis. This inhibitory effect was exerted through direct action of SAK on Plg rather than indirectly on tPA or uPA. Inhibition of Plg activation by SAK is readily abrogated by interaction of SAK with human neutrophil peptides (HNPs). Finally, we show that NH2-terminal residues of SAK are important for the inhibitory effect of SAK on tPA- and uPA-mediated Plg activation. In conclusion, SAK reduces tPA/uPA-mediated Plg activation by means of SAK.Plg complex formation, consequently downregulating tPA/uPA-induced fibrinolysis.

Nyckelord

Adult

Female

Fibrinolysis

drug effects

Humans

Male

Metalloendopeptidases

pharmacology

Middle Aged

Plasmin

antagonists & inhibitors

biosynthesis

Plasminogen

antagonists & inhibitors

Plasminogen Activators

metabolism

Recombinant Proteins

Tissue Plasminogen Activator

Urokinase-Type Plasminogen Activator

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)