CTGF increases vascular endothelial growth factor-dependent angiogenesis in human synovial fibroblasts by increasing miR-210 expression.

Abstract

Connective tissue growth factor (CTGF, a.k.a. CCN2) is inflammatory mediator and abundantly expressed in osteoarthritis (OA). Angiogenesis is essential for OA progression. Here, we investigated the role of CTGF in vascular endothelial growth factor (VEGF) production and angiogenesis in OA synovial fibroblasts (OASFs). We showed that expression of CTGF and VEGF in synovial fluid were higher in OA patients than in controls. Directly applying CTGF to OASFs increased VEGF production then promoted endothelial progenitor cells tube formation and migration. CTGF induced VEGF by raising miR-210 expression via PI3K, AKT, ERK, and nuclear factor-κB (NF-κB)/ELK1 pathways. CTGF-mediating miR-210 upregulation repressed glycerol-3-phosphate dehydrogenase 1-like (GPD1L) expression and PHD activity and subsequently promoted hypoxia-inducible factor (HIF)-1α-dependent VEGF expression. Knockdown of CTGF decreased VEGF expression and abolished OASF-conditional medium-mediated angiogenesis in vitro as well as angiogenesis in chick chorioallantoic membrane and Matrigel-plug nude mice model in vivo. Taken together, our results suggest CTGF activates PI3K, AKT, ERK, and NF-κB/ELK1 pathway, leading to the upregulation of miR-210, contributing to inhibit GPD1L expression and prolyl hydroxylases 2 activity, promoting HIF-1α-dependent VEGF expression and angiogenesis in human synovial fibroblasts.

• Authors: S-C Liu, S-M Chuang, C-J Hsu, C-H Tsai, S-W Wang, C-H Tang
• Journal: Cell death & disease (Cell Death Dis) Vol. 5 Pg. e1485 (Oct 23 2014) ISSN: 2041-4889 [Electronic] England
• PMID: 25341039 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• ELK1 protein, human
• Hypoxia-Inducible Factor 1, alpha Subunit
• MIRN210 microRNA, human
• MicroRNAs
• NF-kappa B
• Vascular Endothelial Growth Factor A
• ets-Domain Protein Elk-1
• Connective Tissue Growth Factor
• EGLN1 protein, human
• Hypoxia-Inducible Factor-Proline Dioxygenases
• Phosphatidylinositol 3-Kinases
• Proto-Oncogene Proteins c-akt
• Extracellular Signal-Regulated MAP Kinases

Topics

• Case-Control Studies
• Connective Tissue Growth Factor (metabolism)
• Extracellular Signal-Regulated MAP Kinases (metabolism)
• Fibroblasts (metabolism, pathology)
• Gene Knockdown Techniques
• Humans
• Hypoxia-Inducible Factor 1, alpha Subunit (metabolism)
• Hypoxia-Inducible Factor-Proline Dioxygenases (metabolism)
• MicroRNAs (metabolism)
• Models, Biological
• NF-kappa B (metabolism)
• Neovascularization, Physiologic
• Osteoarthritis (pathology)
• Phosphatidylinositol 3-Kinases (metabolism)
• Proto-Oncogene Proteins c-akt (metabolism)
• Signal Transduction
• Synovial Membrane (pathology)
• Up-Regulation
• Vascular Endothelial Growth Factor A (metabolism)
• ets-Domain Protein Elk-1 (metabolism)