title: Transforming growth factor-beta promotes recruitment of bone marrow cells and bone marrow-derived mesenchymal stem cells through stimulation of MCP-1 production in vascular smooth muscle cells.
abstract: Bone marrow-derived progenitor cells have recently been shown to be involved in the development of intimal hyperplasia after vascular injury. Transforming growth factor-beta (TGF-beta) has profound stimulatory effects on intimal hyperplasia, but it is unknown whether these effects involve progenitor cell recruitment. In this study we found that although TGF-beta had no direct effect on progenitor cell recruitment, conditioned media derived from vascular smooth muscle cells (VSMC) stimulated with TGF-beta induced migration of both total bone marrow (BM) cells and BM-mesenchymal stem cells (MSC) and also induced MSC differentiation into smooth muscle like cells. Furthermore, overexpression of the signaling molecule Smad3 in VSMC via adenovirus-mediated gene transfer (AdSmad3) enhanced the TGF-beta's chemotactic effect. Microarray analysis of VSMC stimulated by TGF-beta/AdSmad3 revealed monocyte chemoattractant protein-1 (MCP-1) as a likely factor responsible for progenitor cell recruitment. We then demonstrated that TGF-beta through Smad3 phosphorylation induced a robust expression of MCP-1 in VSMC. Recombinant MCP-1 mimicked the stimulatory effect of conditioned media on BM and MSC migration. In the rat carotid injury model, Smad3 overexpression significantly increased MCP-1 expression after vascular injury, consistent with our in vitro results. Interestingly, TGF-beta/Smad3-induced MCP-1 was completely blocked by both Ro-32-0432 and rotterlin, suggesting protein kinase C-delta (PKCdelta) may play a role in TGF-beta/Smad3-induced MCP-1 expression. In summary, our data demonstrate that TGF-beta, through Smad3 and PKCdelta, stimulates VSMC production of MCP-1, which is a chemoattractant for bone marrow-derived cells, specifically MSC. Manipulation of this signaling system may provide a novel approach to inhibition of intimal hyperplasia.
authors.affiliation: Department of Surgery, University of Wisconsin School of Medicine, Madison, Wisconsin 53705, USA.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.forename: Shirling
authors.initials: S
authors.lastname: Tsai
authors.forename: Kaori
authors.initials: K
authors.lastname: Kato
authors.forename: Dai
authors.initials: D
authors.lastname: Yamanouchi
authors.forename: Chunjie
authors.initials: C
authors.lastname: Wang
authors.forename: Shahin
authors.initials: S
authors.lastname: Rafii
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: K Craig
authors.initials: KC
authors.lastname: Kent
mesh_terms: D000800:Angioplasty, Balloon; D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D001854:Bone Marrow Cells / Q000378:metabolism*; D002450:Cell Communication; D002454:Cell Differentiation; D002465:Cell Movement; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002633:Chemotaxis; D020869:Gene Expression Profiling; D006965:Hyperplasia / Q000378:metabolism / Q000473:pathology; D007124:Immunoenzyme Techniques; D008297:Male; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D051745:Protein Kinase C-delta / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D051900:Smad3 Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D013234:Stem Cells; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D017539:Tunica Intima / Q000378:metabolism / Q000473:pathology
chemical_list: D015415:Biomarkers; C491766:Ccl2 protein, rat; D018932:Chemokine CCL2; D012333:RNA, Messenger; D051900:Smad3 Protein; D016212:Transforming Growth Factor beta; D051745:Protein Kinase C-delta