Original Communication| Volume 144, ISSUE 1, P86-92, July 2008

The role of G proteins in thromospondin-1–induced vascular smooth muscle cell migration


      Thrombospondin-1 (TSP-1), which is a matricellular glycoprotein associated with chemotaxis of vascular smooth muscle cells (VSMCs), is relevant to the development of arterial lesions. Evidence suggests that TSP-1 receptors are linked to guanosine triphosphate-binding proteins (G proteins). The purpose of this study was to determine the role of G proteins in TSP-1–induced VSMC chemotaxis and whether this pathway was associated with extracellular signal-regulated kinase 1/2 (ERK) or p38 kinase activation (downstream pathways associated with VSMC chemotaxis).


      In all studies, quiescent VSMCs were preincubated either with serum-free medium, cholera toxin, pertussis toxin, forskolin, or 3-isobutyl-1-methylxanthine. Using a microchemotaxis chamber, preincubated VSMCs were exposed to TSP-1 or serum-free medium. Migrated VSMCs were recorded as cells/5 fields (400×) and analyzed by paired t-test. To evaluate the effect of G proteins on TSP-1–induced ERK or p38 activation, preincubated VSMCs were exposed to serum-free medium or TSP-1 and analyzed by Western immunoblotting. For measurement of intracellular cyclic adenosine monophosphate (cAMP) levels, enzyme-linked immunosorbant assay was performed on preincubated VSMCs exposed to serum-free medium or TSP-1.


      Although pertussis toxin attenuated TSP-1–induced chemotaxis, cholera toxin abolished TSP-1–induced chemotaxis. Cholera toxin, but not pertussis toxin, inhibited both ERK and p38 activation. The cAMP stimulators forskolin and IBMX abolished TSP-1–induced chemotaxis and ERK and p38 activation. Although no changes were observed in cAMP levels in VSMCs treated with serum-free medium, TSP-1, or pertussis toxin, cholera toxin alone significantly increased cAMP levels.


      Gs protein signaling inhibits TSP-1–induced VSMC chemotaxis by increasing the levels of cAMP. Gi signaling is involved in the mechanism of TSP-1 stimulated chemotaxis and warrants additional study. Agents that increase cAMP levels may be beneficial in reducing TSP-1–induced chemotaxis in response to vascular injury.
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        • Baklanov D.V.
        • Peters K.G.
        • Seidel A.L.
        • Taylor D.A.
        • Annex B.H.
        Neovascularization in intimal hyperplasia is associated with vein graft failure after coronary artery bypass surgery.
        Vasc Med. 2003; 8: 163-167
        • Hanyu M.
        • Kume N.
        • Ikeda T.
        • Minami M.
        • Kita T.
        • Komeda M.
        VCAM-1 expression precedes macrophage infiltration into subendothelium of vein grafts interposed into carotid arteries in hypercholesterolemic rabbits—a potential role in vein graft atherosclerosis.
        Atherosclerosis. 2001; 158: 313-319
        • Schepers A.
        • de Vries M.R.
        • van Leuven C.J.
        • Grimbergen J.M.
        • Holers V.M.
        • Daha M.R.
        • et al.
        Inhibition of complement component C3 reduces vein graft atherosclerosis in apolipoprotein E3-Leiden transgenic mice.
        Circulation. 2006; 114: 2831-2838
        • Adams J.C.
        Internat J Biochem Cell Biol. 1997; 29: 861-865
        • Gahtan V.
        • Wang X.J.
        • Willis A.I.
        • Tuszynski G.P.
        • Sumpio B.E.
        Thrombospondin-1 regulation of smooth muscle cell chemotaxis is extracellular signal-regulated protein kinases 1/2 dependent.
        Surgery. 1999; 126: 203-207
        • Raugi G.J.
        • Mullen J.S.
        • Bark D.H.
        • Okada T.
        • Mayberg M.R.
        Thrombospondin deposition in rat carotid artery injury.
        Am J Pathol. 1990; 137: 179-185
        • Gahtan V.
        • Wang X.J.
        • Ikeda M.
        • et al.
        Thrombospondin-1 induces activation of focal adhesion kinase in vascular smooth muscle cells.
        J Vasc Surg. 1999; 29: 1031-1036
        • Baenziger N.L.
        • Brodie G.N.
        • Majerus P.W.
        A thrombin-sensitive protein of human platelet membranes.
        Proc Natl Acad Sci U S A. 1971; 68: 240-243
        • Willis A.I.
        • Fuse S.
        • Wang X.J.
        • Chen E.
        • Tuszynski G.P.
        • Sumpio B.E.
        • et al.
        Inhibition of phosphatidylinositol 3-kinase and protein kinase C attenuates extracellular matrix protein-induced vascular smooth muscle cell chemotaxis.
        J Vasc Surg. 2000; 31: 1160-1167
        • Simon M.I.
        • Strathmann M.P.
        • Gautam N.
        Diversity of G proteins in signal transduction.
        Science. 1991; 252: 802-808
        • Wilkie T.M.
        • Gilbert D.J.
        • Olsen A.S.
        • Chen X.N.
        • Amatruda T.T.
        • Korenberg J.R.
        • et al.
        Evolution of the mammalian G protein alpha subunit multigene family.
        Nat Genet. 1992; 1: 85-91
        • Zolk O.
        • Kouchi I.
        • Schnabel P.
        • Böhm M.
        Heterotrimeric G proteins in heart disease.
        Can J Physiol Pharmacol. 2000; 78: 187-198
        • Lester B.R.
        • McCarthy J.B.
        • Sun Z.Q.
        • Smith R.S.
        • Furcht L.T.
        • Spiegel A.M.
        G-protein involvement in matrix-mediated motility and invasion of high and low experimental metastatic B16 melanoma clones.
        Cancer Res. 1989; 49: 5940-5948
        • Mansfield P.J.
        • Suchard S.J.
        Thrombospondin promotes chemotaxis and haptotaxis of human peripheral blood monocytes.
        J Immunol. 1994; 153: 4219-4229
        • Nelson P.R.
        • Yamamura S.
        • Kent K.C.
        Extracellular matrix proteins are potent agonists of human smooth muscle cell migration.
        J Vasc Surg. 1996; 24 (discussion 32-3): 25-32
        • Suchard S.J.
        • Mansfield P.J.
        Neutrophil thrombospondin receptors are linked to GTP-binding proteins.
        J Cell Physiol. 1996; 168: 217-227
        • Mills I.
        • Cohen C.R.
        • Kamal K.
        • Li G.
        • Shin T.
        • Du W.
        • et al.
        Strain activation of bovine aortic smooth muscle cell proliferation and alignment: study of strain dependency and the role of protein kinase A and C signaling pathways.
        J Cell Physiol. 1997; 170: 228-234
        • Palmer D.
        • Tsoi K.
        • Maurice D.H.
        Synergistic inhibition of vascular smooth muscle cell migration by phosphodiesterase 3 and phosphodiesterase 4 inhibitors.
        Circ Res. 1998; 82: 852-861
        • Boerth N.J.
        • Dey N.B.
        • Cornwell T.L.
        • Lincoln T.M.
        Cyclic GMP-dependent protein kinase regulates vascular smooth muscle cell phenotype.
        J Vasc Res. 1997; 34: 245-259
        • Johnson R.
        • Webb J.G.
        • Newman W.H.
        • Wang Z.
        Regulation of human vascular smooth muscle cell migration by beta-adrenergic receptors.
        Am Surg. 2006; 72: 51-54
        • Guo N.
        • Zabrenetzky V.S.
        • Chandrasekaran L.
        • Sipes J.M.
        • Lawler J.
        • Krutzsch H.C.
        • et al.
        Differential roles of protein kinase C and pertussis toxin-sensitive G-binding proteins in modulation of melanoma cell proliferation and motility by thrombospondin 1.
        Cancer Res. 1998; 58: 3154-3162
        • Wang X.Q.
        • Lindberg F.P.
        • Frazier W.A.
        Integrin-associated protein stimulates alpha2beta1-dependent chemotaxis via Gi-mediated inhibition of adenylate cyclase and extracellular-regulated kinases.
        J Cell Biol. 1999; 147: 389-400