RESUMO
Bioactive ceramics have interesting properties from the biological standpoint, but their effects on cellular events remain partially unknown. In the current work, we investigated cellular viability, proliferation, and metabolic activity of rat primary osteoblasts in contact with four different samples: type I collagen, bioactive glass-coated collagen (GC), and both samples submitted to immersion for 5 days in a simulated body fluid. The bioactive glass coating was obtained from a sol-gel process. The cell viability, the alkaline phosphate, the collagen secretion, and the nitric oxide production by osteoblast were measured after 72 h of incubation in the presence of the samples. The GC that was immersed for 5 days in a simulated body fluid solution showed an increase in osteoblast viability and proliferation when it was compared with control and the other samples.
Assuntos
Substitutos Ósseos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Colágeno Tipo I/farmacologia , Vidro , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/análise , Animais , Substitutos Ósseos/química , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Colágeno Tipo I/química , Osteoblastos/enzimologia , Ratos , Ratos Wistar , Propriedades de SuperfícieRESUMO
Cementum is a mineralized tissue that lines the surface of the tooth root enabling attachment of the periodontal ligament to the root and surrounding alveolar bone. Studies examining the mechanisms involved in the formation of root cementum have been hindered by an inability to isolate and culture the cells required for cementum production (cementoblasts). This study isolated and characterized cementoblast cells derived from rat molar periodontal ligament. It was observed that the isolated cells expressed F-Spondin, a cementoblast marker, while F-Spondin expression was not observed in the cells of other tissues such as gingival fibroblasts and osteoblasts. As expected, the isolated cementoblast cells also expressed osteocalcin (OC), bone sialoprotein (BSP), alkaline phosphatase (ALP), and type I collagen, demonstrating the presence of mineralized tissues genes in cementoblast cells. These cells showed high ALP activity and calcified nodule formation in vitro. Since cementogenesis could be a critical event for regeneration of periodontal tissues, this study investigated whether bioactive glass particles could affect the proliferation of cementoblasts since they are known to enhance osteoblast proliferation. It was found that the ionic products from bioactive glass nanoparticles increased cementoblast viability, mitochondrial activity, and induced cell proliferation. Together, these results show the characterization of cementoblast cells from rat molar periodontal ligament. Additionally, it was shown that bioactive glass nanoparticles induced cementoblast to proliferate, indicating that they could be a potential material for use in cement regeneration through tissue engineering.
Assuntos
Proliferação de Células , Cemento Dentário/citologia , Vidro/química , Nanopartículas/química , Animais , Antígenos de Diferenciação/biossíntese , Sobrevivência Celular , Células Cultivadas , Cemento Dentário/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Dente Molar/citologia , Dente Molar/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Peptídeos/metabolismo , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Ratos , Ratos WistarRESUMO
Previous studies have demonstrated the absorption of porcine trypsin in isolated jejunal loops from male Wistar rats by open-loop perfusion. The possible routes of absorption were examined in the study reported here. Trypsin (0.5 mg/ml) was dissolved in tyrode solution and perfused at a rate of 0.5 ml/min, at 37 degrees C, for 40 min. Using immunoperoxidase and immunofluorescence techniques, strong reactivity towards anti-TLCK-trypsin antibody was demonstrated through out the enterocyte cytosol. The present data indicate that trypsin was absorbed by enterocytes, probably through a transcellular route.