The ADMA/DDAH pathway is a critical regulator of endothelial cell motility.
Asymmetric dimethylarginine (ADMA) is an inhibitor of nitric oxide production associated with abnormal blood vessel growth and repair, however, the mechanism of action of ADMA is not well understood. We studied the role of exogenous and endogenous ADMA in the regulation of cell motility and actin cytoskeleton in porcine pulmonary endothelial cells (PAECs) and pulmonary microvascular endothelial cells (PMECs) from knockout mice that lack one of the enzyme metabolising ADMA, dimethylarginine dimethylaminohydrolase I (DDAHI) as well as endothelial cells overexpressing DDAH in vitro. We show that ADMA induced stress fibre and focal adhesion formation and inhibited cell motility in primary pulmonary endothelial cells. The effects of ADMA depended on the activity of RhoA and Rho kinase and were reversed by overexpression of DDAH, nitric oxide donors and protein kinase G activator, 8-bromo-cGMP. ADMA also inhibited the activities of Rac1 and Cdc42 in cells but these changes had a minor effect on cell motility. Endogenous ADMA increased RhoA activity and inhibited cell motility in PMECs from DDAHI knockout mice and inhibited angiogenesis in vitro. These results are the first demonstration that metabolism of cardiovascular risk factor ADMA regulates endothelial cell motility, an important factor in angiogenesis and vascular repair.
Wojciak-Stothard
Beata
B
BHF Laboratories, Department of Medicine, University College London, 5 University Street, London, WC1 E6JJ, UK. B.Wojciak-Stothard@ucl.ac.uk
Torondel
Belen
B
Tsang
Lillian Yen Fen
LY
Fleming
Ingrid
I
Fisslthaler
Beate
B
Leiper
James M
JM
Vallance
Patrick
P
D008841:Actin Cytoskeleton / Q000187:drug effects / Q000502:physiology; D000581:Amidohydrolases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000031:analogs & derivatives / Q000494:pharmacology; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology; D042783:Endothelial Cells / Q000187:drug effects / Q000502:physiology*; D004789:Enzyme Activation; D022001:Focal Adhesions / Q000502:physiology; D008168:Lung / Q000098:blood supply / Q000166:cytology; D051379:Mice; D018345:Mice, Knockout; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D015398:Signal Transduction; D022502:Stress Fibers / Q000502:physiology; D013552:Swine; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism; D020830:rac1 GTP-Binding Protein / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000378:metabolism; D020743:rhoB GTP-Binding Protein / Q000378:metabolism
C016276:8-bromocyclic GMP; C018524:N,N-dimethylarginine; D001120:Arginine; D017869:Cyclic GMP-Dependent Protein Kinases; D000581:Amidohydrolases; C059999:dimethylargininase; D020764:cdc42 GTP-Binding Protein; D020830:rac1 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein; D020743:rhoB GTP-Binding Protein; D006152:Cyclic GMP