Lack of 2-antiplasmin promotes re-endothelialization via over-release of VEGF after vascular injury in mice

We here report that the arterial blood flow after endothelial injury in mice deficient in alpha 2-antiplasmin (alpha 2-AP-/- mice) was well maintained compared with that of wild-type mice. Moreover, the development of neointima 4 weeks after injury in alpha 2-AP-/- mice was significantly decreased. Histologic observations showed a prompt recovery of endothelial cells with a much higher proliferating index in repaired endothelium in alpha 2-AP-/- mice. The amount of secreted vascular endothelial growth factor (VEGF) by explanted vascular smooth muscle cells (SMCs) from alpha 2-AP-/- mice was significantly increased. In separate experiments using a human endothelial cell (EC) line, we could demonstrate that plasminogen binds to ECs and that this binding can be prevented by alpha 2-AP. Finally, an injection of either an anti-VEGF receptor-1 antibody or alpha 2-AP reduced the prompt endothelial healing. alpha 2-AP is the main inactivator of plasmin, which cleaves extracellular matrix-bound VEGF to release a diffusible proteolytic fragment. Lack of alpha 2-AP, therefore, could lead to a local over-release of VEGF by the continuously active plasmin in the injured area, which could result in a prompt re-endothelialization after vascular injury. Our results provide new insight into the role of alpha 2-AP and VEGF in the pathogenesis of re-endothelialization following vascular injury.

[1]  D. Gospodarowicz,et al.  Isolation and characterization of a newly identified endothelial cell mitogen produced by AtT‐20 cells. , 1989, The EMBO journal.

[2]  N. Ferrara,et al.  Molecular and biological properties of the vascular endothelial growth factor family of proteins. , 1992, Endocrine reviews.

[3]  M. Karkkainen,et al.  Lymphatic endothelium: a new frontier of metastasis research , 2002, Nature Cell Biology.

[4]  J. Isner,et al.  Local delivery of vascular endothelial growth factor accelerates reendothelialization and attenuates intimal hyperplasia in balloon-injured rat carotid artery. , 1995, Circulation.

[5]  Kenneth J. Hillan,et al.  Heterozygous embryonic lethality induced by targeted inactivation of the VEGF gene , 1996, Nature.

[6]  A. Hara,et al.  Lack of α2-antiplasmin promotes pulmonary heart failure via overrelease of VEGF after acute myocardial infarction , 2002 .

[7]  M. Dewerchin,et al.  Characterization and Targeting of the Murine α2-Antiplasmin Gene , 1997, Thrombosis and Haemostasis.

[8]  M. Dake,et al.  Inhibition of vascular endothelial growth factor-mediated neointima progression with angiostatin or paclitaxel. , 2002, Journal of vascular and interventional radiology : JVIR.

[9]  J. Paramo,et al.  Development and clinical application of a new ELISA assay to determine plasmin–α2‐antiplasmin complexes in plasma , 1996, British journal of haematology.

[10]  ToshihikoUematsu,et al.  Inhibition of von Willebrand Factor Binding to Platelet GP Ib by a Fractionated Aurintricarboxylic Acid Prevents Restenosis After Vascular Injury in Hamster Carotid Artery , 1997 .

[11]  J. Mills,et al.  Vein adaptation to arterialization in an experimental model. , 2001, Journal of vascular surgery.

[12]  B. Schlott,et al.  Characterization of the interaction between plasminogen and staphylokinase. , 1994, European journal of biochemistry.

[13]  O. Matsuo,et al.  Analysis of complex formation between plasmin(ogen) and staphylokinase or streptokinase. , 2001, Archives of biochemistry and biophysics.

[14]  J. Isner,et al.  Antibody blockade of thrombospondin accelerates reendothelialization and reduces neointima formation in balloon-injured rat carotid artery. , 1999, Circulation.

[15]  W. Klepetko,et al.  Co-expression of endothelin-1 and vascular endothelial growth factor mediates increased vascular permeability in lung grafts before reperfusion. , 2002, The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation.

[16]  P. Carmeliet,et al.  Targeted gene manipulation and transfer of the plasminogen and coagulation systems in mice , 1996 .

[17]  K. Alitalo,et al.  Signaling via vascular endothelial growth factor receptors. , 1999, Experimental cell research.

[18]  A. Bayés‐Genís,et al.  Elevated levels of plasmin-alpha2 antiplasmin complexes in unstable angina. , 1999, Thrombosis and haemostasis.

[19]  O. Kozawa,et al.  Plasmin Generation Plays different Roles in the Formation and Removal of Arterial and Venous Thrombus in Mice , 2002, Thrombosis and Haemostasis.

[20]  P. Carmeliet,et al.  Physiological consequences of loss of plasminogen activator gene function in mice , 1994, Nature.

[21]  P. Carmeliet,et al.  Insights in Vessel Development and Vascular Disorders Using Targeted Inactivation and Transfer of Vascular Endothelial Growth Factor, the Tissue Factor Receptor, and the Plasminogen System , 1997, Annals of the New York Academy of Sciences.

[22]  J. Hartikainen,et al.  Intravascular Adenovirus-Mediated VEGF-C Gene Transfer Reduces Neointima Formation in Balloon-Denuded Rabbit Aorta , 2000, Circulation.

[23]  R. Lucius,et al.  Vascular endothelial growth factor induces chemotaxis and proliferation of microglial cells , 2002, Journal of Neuroimmunology.

[24]  M. Dewerchin,et al.  Alpha2-antiplasmin gene deficiency in mice is associated with enhanced fibrinolytic potential without overt bleeding. , 1999, Blood.

[25]  H. Deckmyn,et al.  Inhibition of integrin function by a cyclic RGD-containing peptide prevents neointima formation. , 1994, Circulation.

[26]  W. Risau,et al.  Systemic hypoxia changes the organ-specific distribution of vascular endothelial growth factor and its receptors. , 1998, Proceedings of the National Academy of Sciences of the United States of America.

[27]  B. Wiman,et al.  Molecular mechanism of physiological fibrinolysis , 1978, Nature.

[28]  A. Bayés‐Genís,et al.  Elevated Levels of Plasmin-α2 Antiplasmin Complexes in Unstable Angina , 1999, Thrombosis and Haemostasis.

[29]  J. Isner,et al.  Divergence of Angiogenic and Vascular Permeability Signaling by VEGF: Inhibition of Protein Kinase C Suppresses VEGF-Induced Angiogenesis, but Promotes VEGF-Induced, NO-Dependent Vascular Permeability , 2002, Arteriosclerosis, thrombosis, and vascular biology.

[30]  R. Ross,et al.  A platelet-dependent serum factor that stimulates the proliferation of arterial smooth muscle cells in vitro. , 1974, Proceedings of the National Academy of Sciences of the United States of America.

[31]  J. Winer,et al.  Dual regulation of vascular endothelial growth factor bioavailability by genetic and proteolytic mechanisms. , 1992, The Journal of biological chemistry.

[32]  O. Kozawa,et al.  Differential Role of Components of the Fibrinolytic System in the Formation and Removal of Thrombus Induced by Endothelial Injury , 1999, Thrombosis and Haemostasis.