COMP-Ang1 enhances DNA synthesis and cell cycle progression in human periodontal ligament cells via Tie2-mediated phosphorylation of PI3K/Akt and MAPKs.
Recombinant COMP-Ang1, a chimera of angiopoietin-1 (Ang1), and a short coiled-coil domain of cartilage oligomeric matrix protein (COMP) can stimulate multiple cellular processes. Proliferative capacity of periodontal ligament (PDL) fibroblasts (PLFs) is important for maintaining PDL integrity and homeostasis. In this study, we explored whether exogenous COMP-Ang1 addition enhances proliferation of human PLFs and the cellular mechanisms therein. We initially isolated and characterized PLFs, where the cells showed highly positive staining for surface markers, CD90, CD105, and CD146. COMP-Ang1 treatment increased proliferation of PLFs by stimulating migration of cells into S and G2/M phases. This increase was coupled with decreased p21(Cip) and p27(Kip) levels and enhanced cyclin D1, cyclin-dependent kinase (CDK) 2, and CDK4 induction. Transfection with si-Tie2 near completely blocked COMP-Ang1-stimulated cell cycle progression in PLFs. Tie2 knockdown also inhibited COMP-Ang1-induced phosphorylation of mitogen-activated protein kinases (MAPKs). In addition, COMP-Ang1-mediated activation of Akt and c-Jun was suppressed by treating each of pharmacological inhibitors specific to phosphoinositide 3-kinase (PI3K) (LY294002 and Wortmannin) or MAPKs (PD98059, SB203580, and SP600125). Similarly, COMP-Ang1-mediated increases in DNA synthesis and cyclin D1 induction were prevented by treating inhibitor of MAPKs and PI3K or by c-Jun knockdown. These results suggest that COMP-Ang1 enhances survival and proliferation of human PLFs through the activation of Tie2-mediated signaling, where PI3K/Akt and MAPK-c-Jun signaling pathways act as downstream effectors. Collectively, COMP-Ang1 may be a useful as a stimulator of human PLFs and therefore improves PDL integrity and homeostasis.
Department of Oral and Maxillofacial Surgery, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, 03080, South Korea.
Shin-Saeng
SS
Lim
Department of Bioactive Material Sciences, Research Center of Bioactive Materials, Chonbuk National University, Jeonju, 54896, South Korea.|Cluster for Craniofacial Development & Regeneration Research, Institute of Oral Biosciences and School of Dentistry, Chonbuk National University, Jeonju, 54896, South Korea.
Sung-Ho
SH
Kook
Department of Bioactive Material Sciences, Research Center of Bioactive Materials, Chonbuk National University, Jeonju, 54896, South Korea. leejc88@jbnu.ac.kr.|Cluster for Craniofacial Development & Regeneration Research, Institute of Oral Biosciences and School of Dentistry, Chonbuk National University, Jeonju, 54896, South Korea. leejc88@jbnu.ac.kr.|Institute of Oral Biosciences and School of Dentistry, Chonbuk National University, Jeonju, 54896, South Korea. leejc88@jbnu.ac.kr.
Jeong-Chae
JC
Lee
D000328:Adult; D042683:Angiopoietin-1 / Q000235:genetics / Q000494:pharmacology*; D064236:Cartilage Oligomeric Matrix Protein / Q000235:genetics / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects*; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D008297:Male; D010513:Periodontal Ligament / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D042787:Receptor, TIE-2 / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000494:pharmacology*
D042683:Angiopoietin-1; D064236:Cartilage Oligomeric Matrix Protein; D004247:DNA; D048049:Extracellular Signal-Regulated MAP Kinases; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D042787:Receptor, TIE-2; D011993:Recombinant Fusion Proteins; C467630:ANGPT1 protein, human; C577553:TSP5 protein, human
COMP-Ang1; Cell cycle regulatory factors; Human periodontal ligament fibroblasts; Proliferation; Signal transduction pathway; Tie2