Key role of Src kinase in S100B-induced activation of the receptor for advanced glycation end products in vascular smooth muscle cells.
The receptor for advanced glycation end products (RAGE) and its ligands have been implicated in the activation of oxidant stress and inflammatory pathways in vascular smooth muscle cells (VSMCs) leading to the initiation and augmentation of atherosclerosis. Here we report that non-receptor Src tyrosine kinase and the membrane protein caveolin-1 (Cav-1) play a key role in the activation of RAGE by S100B in VSMCs. S100B increased the activation of Src kinase and tyrosine phosphorylation of caveolin-1 in VSMCs. A RAGE-specific antibody blocked both these effects. An inhibitor of Src kinase, PP2, significantly blocked S100B-induced activation of Src kinase, mitogen-activated protein kinases, transcription factors NF-kappaB and STAT3, superoxide production, tyrosine phosphorylation of Cav-1, VSMC migration, and expression of the pro-inflammatory genes monocyte chemotactic protein-1 and interleukin-6. Cholesterol depletion also inhibited S100B-induced effects indicating the requirement for intact caveolae in RAGE-specific signaling. Nucleofection of either a Src dominant negative mutant, or a Cav-1 mutant lacking the scaffolding domain, or Cav-1 short hairpin RNA significantly reduced S100B-induced inflammatory gene expression in VSMCs. Furthermore, VSMCs derived from insulin-resistant and diabetic db/db mice displayed increased RAGE expression, Src activation, and migration compared with those from control db/+ mice. The RAGE antibody blocked enhanced migration in db/db cells. These studies demonstrate for the first time that, in VSMCs, Src kinase and Cav-1 play important roles in RAGE-mediated inflammatory gene expression and migration, key events associated with diabetic vascular complications.
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Marpadga A
MA
Reddy
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Shu-Lian
SL
Li
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Saurabh
S
Sahar
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Young-Sook
YS
Kim
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Zhong-Gao
ZG
Xu
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010.
Linda
L
Lanting
Department of Diabetes, Beckman Research Institute of the City of Hope, Duarte, California 91010. Electronic address: RNatarajan@coh.org.
Rama
R
Natarajan
D000818:Animals; D051242:Caveolin 1 / Q000378:metabolism; D002465:Cell Movement; D018932:Chemokine CCL2 / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2; D005786:Gene Expression Regulation; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D009414:Nerve Growth Factors / Q000494:pharmacology*; D018384:Oxidative Stress; D021381:Protein Transport; D051381:Rats; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic / Q000378:metabolism*; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000494:pharmacology*; D050796:STAT3 Transcription Factor / Q000378:metabolism; D013552:Swine; D050863:Synaptotagmin I / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism*
D051242:Caveolin 1; D018932:Chemokine CCL2; D015850:Interleukin-6; D016328:NF-kappa B; D009414:Nerve Growth Factors; D000067759:Receptor for Advanced Glycation End Products; D011971:Receptors, Immunologic; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579160:S100B protein, human; C579159:S100b protein, mouse; C579158:S100b protein, rat; D050796:STAT3 Transcription Factor; D050863:Synaptotagmin I; D019061:src-Family Kinases; D020928:Mitogen-Activated Protein Kinases