Interleukin-18/WNT1-inducible signaling pathway protein-1 signaling mediates human saphenous vein smooth muscle cell proliferation

✍ Scribed by Venkatapuram Seenu Reddy; Anthony J. Valente; Patrice Delafontaine; Bysani Chandrasekar

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 737 KB
• Volume: 226
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.22676

✦ Synopsis

We demonstrate for the first time that the pro-inflammatory cytokine interleukin (IL)-18 stimulates rapid and significant proliferation of SMC derived from human saphenous vein (VSMC), but not coronary artery. IL-18 also stimulates VSMC growth. Further investigations revealed that IL-18-induced VSMC proliferation was Wnt inducible secreted protein-1 (WISP1) dependent. In addition to inducing its own expression via phosphatidylinositol 3-kinase/Akt-dependent IKK/NF-kB activation, IL-18 stimulated glycogen synthase kinase 3b phosphorylation and degradation, b-catenin nuclear translocation and stabilization, T-cell factor-lymphoid enhancer binding factor (TCF-LEF) activation, and WISP1 induction. Moreover, WISP1 induced its own expression, and that of survivin and multiple matrix metalloproteinases via b-catenin/TCF-LEF interaction. WISP1 also activated AP-1, but not NF-kB, and induced matrix metalloproteinase (MMP)9 transcription in part via AP-1. Interestingly, WISP1 failed to regulate tissue inhibitors of matrix metalloproteinases (TIMP) expression. These novel findings indicate that IL-18 induces a series of signaling events that result in WISP1-mediated VSMC proliferation, survival and MMP induction that are key components of vein graft stenosis and this may be amplified by IL-18 and WISP1 autoregulation and cross-regulation.