title: Effects of TGF-β1 on mineralization mediated by rat calvaria-derived osteogenic cells.
abstract: In this study, we have analyzed the viability and cell growth, as well as, the mineralization of extracellular matrix (ECM) by alizarin red and von Kossa staining of calvaria-derived osteogenic cultures, treated with TGF-β1 alone or associated with Dex comparing with acid ascorbic (AA) + β-glicerophosphate (βGP) (positive mineralization control). The expression of the noncollagenous proteins bone sialoprotein (BSP), osteopontin (OPN) and fibronectin (FN) were evaluated by indirect immunofluorescence. In addition, the main ultrastructural morphological findings were assessed by transmission electron microscopy. Osteogenic cells were isolated of calvaria bone from newborn (2-day-old) Wistar rats were treated with TGF-β1 alone or with dexamethasone for 7, 10, and 14 days. As positive mineralization control, the cells were supplemented only with AA+ βGP. As negative control, the cells were cultured with basal medium (α-MEM + 10%FBS + 1%gentamicin). The treatment with TGF-β1, even when combined with Dex, decreased the viability and cell growth when compared with the positive control. Osteoblastic cell cultures were positive to alizarin red and von Kossa stainings after AA + βGP and Dex alone treatments. Positive immunoreaction was found for BSP, OPN and FN in all studied treatments. Otherwise, when the cell cultures were supplemented with TGF-β1 and TGF-β1 + Dex, no mineralization was observed in any of the studied periods. These present findings suggest that TGF-β1, in the studied in vitro doses, inhibits the proliferation and differentiation of osteoblastic cells by impairment of nodule formation.
authors.affiliation: Department of Biomaterials and Oral Biology, Laboratory of Oral Biology, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Tatiani A G
authors.initials: TA
authors.lastname: Donato
authors.affiliation: Department of Biomaterials and Oral Biology, Laboratory of Oral Biology, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.|Department of Oral Pathology, São Leopoldo Mandic Institute and Research Center, Campinas, SP, Brazil.
authors.forename: Elizabeth F
authors.initials: EF
authors.lastname: Martinez
authors.affiliation: Department of Biomaterials and Oral Biology, Laboratory of Oral Biology, School of Dentistry, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Victor E
authors.identifier: http://orcid.org/0000-0002-6767-7812
authors.initials: VE
authors.lastname: Arana-Chavez
mesh_terms: D000818:Animals; D000880:Anthraquinones; D002113:Calcification, Physiologic / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D046529:Microscopy, Electron, Transmission; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010012:Osteogenesis / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000166:cytology; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
chemical_list: D000880:Anthraquinones; D053773:Transforming Growth Factor beta1; C010078:alizarin
keywords: TGF-beta1; dexamethasone; osteoblastic differentiation; osteoprogenitor cells; transmission electron microscopy