PR-39 coordinates changes in vascular smooth muscle cell adhesive strength and locomotion by modulating cell surface heparan sulfate–matrix interactions

✍ Scribed by John H. Chon; Michelle M. Houston; Chengpei Xu; Elliot L. Chaikof

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 308 KB
• Volume: 189
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1050

✦ Synopsis

Abstract

PR‐39 is proline‐rich peptide produced at sites of tissue injury. While the functional properties of this peptide have not been fully defined, PR‐39 may be an important regulator of processes related to cell‐matrix adhesion since it reportedly upregulates syndecan‐4, which is a critical determinant of focal adhesion formation. The ability of PR‐39 to modulate the adhesion and chemokinetic migration behavior of arterial smooth muscle cells (SMCs) in a fashion coordinated with syndecan‐4 expression was investigated. Treatment of SMCs with PR‐39 did not alter syndecan‐1 mRNA, but did induce a two‐fold increase in syndecan‐4 mRNA (P < 0.0001) and significantly enhanced cell surface expression of both syndecan‐4 (P < 0.01) and heparan sulfate (HS) (P < 0.05). These observations were consistent with an observed increase in cell‐matrix adhesive strength (P < 0.05) and a reduction in cell speed (P < 0.01) on fibronectin‐coated substrates. Incubation of PR‐39 treated cells with a soluble fibronectin derived heparin‐binding peptide, as a competitive inhibitor of heparan sulfate/matrix interactions, abolished these effects. These data suggest that PR‐39 mediated alterations of cell adhesion and motility may be related, in part, to the increased expression of heparan sulfate glycosaminoglycans (GAGs) that accompany the upregulation of cell surface syndecan‐4. Futhermore, this investigation supports the notion that factors which control syndecan‐4 expression may play an important role in regulating adhesion related cell processes. © 2001 Wiley‐Liss, Inc.