RESUMO
Osteoblast differentiation and extracellular matrix production are pivotal processes for implant osseointegration or bone tissue engineering. We hypothesized that a biomimetic coating on titanium surfaces, consisting of apatite and amelogenin, would promote such processes. Human Embryonic Palatal Mesenchymal pre-osteoblasts were used as a model for the evaluation of cell adhesion and spreading patterns, as well as mRNA expression of certain osteoblastic gene products. Real-time PCR showed significant (p < 0.05) increase in expression of type I collagen, alkaline phosphatase, and osteocalcin from cells grown on titanium with an apatite/amelogenin composite, as compared with that from cells grown on a pure titanium or apatite coating only. Osteocalcin expression was specifically stimulated by amelogenin added to the culture media. Enhanced attachment and cell spreading were also observed. The biomimetic coating promoting cell adhesion and osteoblast differentiation may have great potential for future dental and biomedical applications.
Assuntos
Apatitas/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Proteínas do Esmalte Dentário/farmacologia , Osteoblastos/efeitos dos fármacos , Osteogênese/genética , Titânio/química , Fosfatase Alcalina/análise , Amelogenina , Apatitas/química , Materiais Biomiméticos/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Colágeno Tipo I/análise , Proteínas do Esmalte Dentário/química , Matriz Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica , Humanos , Mesoderma/citologia , Mesoderma/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Osteocalcina/análise , Osteogênese/efeitos dos fármacosRESUMO
The transcription factor Cbfa1 regulates osteoblast differentiation and expression of genes necessary for the development of a mineralized phenotype. The purpose of this study was to determine if Cbfa1 and BSPII gene expression are influenced by implant surface microtopography. Osteoblasts were cultured on 600-grit (grooved) or sandblasted (roughened) cpTi implant discs. Mineralization was evaluated by Alizarin-Red-S staining. Real Time PCR was used for quantitative analysis of Cbfa1 and BSPII gene expression. Enhanced mineralization was seen in osteoblasts grown on roughened implant surfaces relative to tissue culture plastic. Real Time PCR showed significant (P < 0.05) increases in Cbfa1 gene expression in cells grown on roughened, as compared with grooved, implant surfaces. BSPII gene expression was also increased on rough surfaces in the UMR cells, but was reduced in the rat calvarial osteoblast cultures. These results suggest that osteoblast gene expression and mineralization are affected by roughened implant surface microtopographies during osseointegration of dental implants.
