title: Ascorbate-induced osteoblast differentiation recruits distinct MMP-inhibitors: RECK and TIMP-2.
abstract: The bone formation executed by osteoblasts represents an interesting research field both for basic and applied investigations. The goal of this work was to evaluate the molecular mechanisms involved during osteoblast differentiation in vitro. Accordingly, we demonstrated that, during the osteoblastic differentiation, TIMP-2 and RECK presented differential expressions, where RECK expression was downregulated from the 14th day in contrast with an increase in TIMP-2. Concomitantly, our results showed a temporal regulation of two major signaling cascades during osteoblast differentiation: proliferation cascades in which RECK, PI3 K, and GSK-3beta play a pivotal role and latter, differentiation cascades with participation of Ras, Rho, Rac-1, PKC alpha/beta, and TIMP-2. Furthermore, we observed that phosphorylation level of paxillin was downregulated while FAK(125) remained unchangeable, but active during extracellular matrix (ECM) remodeling. Concluding, our results provide evidences that RECK and TIMP-2 are involved in the control of ECM remodeling in distinct phases of osteoblast differentiation by modulating MMP activities and a multitude of signaling proteins governs these events.
authors.affiliation: Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Cidade Universitária, 13083-970, Campinas, Sao Paulo, Brazil. wzamba@unicamp.br
authors.forename: Willian F
authors.initials: WF
authors.lastname: Zambuzzi
authors.forename: Claudia L
authors.initials: CL
authors.lastname: Yano
authors.forename: Alexandre D M
authors.initials: AD
authors.lastname: Cavagis
authors.forename: Maikel P
authors.initials: MP
authors.lastname: Peppelenbosch
authors.forename: José Mauro
authors.initials: JM
authors.lastname: Granjeiro
authors.forename: Carmen V
authors.initials: CV
authors.lastname: Ferreira
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D002453:Cell Cycle; D002454:Cell Differentiation; D002478:Cells, Cultured; D005109:Extracellular Matrix / Q000378:metabolism; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11 / Q000378:metabolism; D015398:Signal Transduction; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism*; D020830:rac1 GTP-Binding Protein / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; C492025:Reck protein, mouse; D019716:Tissue Inhibitor of Metalloproteinase-2; D011493:Protein Kinase C; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D020830:rac1 GTP-Binding Protein; D020741:rho GTP-Binding Proteins; D001205:Ascorbic Acid