RESUMO
Gene transfer of key regulators of osteogenesis for mesenchymal stem cells represents a promising strategy to regenerate bone. It has been reported that LMP3, a transcription variant of LIM domain mineralization protein (LMP) lacking LIM domains, can induce osteogenesis in vitro and in vivo. As little is known about the effects of LMP3 gene therapy on periodontal ligament (PDL) cell osteogenic differentiation, this study sought to explore whether gene delivery of LMP3 can promote PDL cell mineralization and bone formation. Our results showed that adenoviral mediated gene transfer of LMP3 (AdLMP3) significantly upregulated ALP (Alkaline Phosphatase), BSP (Bone Sialoprotein) and BMP2 gene expression and increased in vitro matrix mineralization in human PDL. Although AdLMP3 gene delivery to PDL cells did not induce ectopic bone formation in vivo, we found that AdLMP3 augments new bone formation, which co-delivered with AdBMP7 gene transfer. Our study provides the evidence that there is a synergistic effect between LMP3 and BMP-7 in vivo, suggesting that LMP3 delivery may be used to augment BMP-mediated osteogenesis. LMP3 and BMP-7 combinatory gene therapy may also have specific applications for oral and periodontal regenerative medicine.
Assuntos
Proteína Morfogenética Óssea 7/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Ligamento Periodontal/fisiologia , Regeneração/genética , Adenoviridae/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Matriz Óssea/metabolismo , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 7/metabolismo , Calcificação Fisiológica , Diferenciação Celular , Linhagem Celular , Vetores Genéticos/genética , Humanos , Sialoproteína de Ligação à Integrina/genética , Sialoproteína de Ligação à Integrina/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Ligamento Periodontal/citologia , Transformação Genética , Regulação para CimaRESUMO
Periostin, a matricellular adapter protein highly expressed by periodontal ligament fibroblasts, is implicated in the maintenance of periodontal integrity, which is compromised during periodontal diseases. The aim of this study was to explore the influence of chronic periodontal inflammation on tissue periostin levels. Periodontal breakdown was induced in a pre-clinical ligature periodontal inflammatory disease model. Periodontal tissue specimens were harvested at baseline, 2 weeks, and 4 weeks and prepared for histologic, immunofluorescence, and micro-CT examination. Statistical analyses were conducted by Kruskal-Wallis, Mann-Whitney, and Spearman's tests. Periostin detection levels were reduced over time in response to the inflammatory process (1 ± 0.05; 0.67 ± 0.03; 0.31 ± 0.02; p < 0.001; baseline, 2, and 4 weeks, respectively). Simultaneously, alveolar bone loss increased from baseline to the 2- and 4-week time-points (0.40 ± 0.02 mm; 1.39 ± 0.08 mm; 1.33 ± 0.15 mm; p < 0.001), which was inversely correlated with the levels of periostin (ρ = -0.545; p < 0.001). In conclusion, periostin PDL tissue levels significantly decrease under chronic inflammatory response and correlate with the detrimental changes to the periodontium over time.