BACKGROUND: Previously, we reported that low-intensity laser irradiation accelerated bone formation, and that this mechanism deeply involved insulin-like growth factor I expression. However, as bone formation is supported by many local factors, the mechanism involved in laser irradiation remains incompletely understood. Therefore, the purpose of this study was to determine the effects of laser irradiation on the osteogenic response in vitro. METHODS: Mouse osteoblast-like cells, MC3T3-E1, were cultured and were irradiated for 5-20 minutes (0.96-3.82 J/cm(2)) at the subconfluent stage using a low-intensity Ga-Al-As diode laser apparatus. After laser irradiation, expression of bone morphogenetic proteins (BMPs), transcription factors (Runx2, Osterix, Dlx5, Msx2), and phosphorylation of Smad1 were determined, and calcium content of cell cultures was also determined. RESULTS: Irradiation at 1.91 J/cm(2) significantly increased the expression of BMPs and Runx2, Osterix, Dlx5, Msx2, and the phosphorylation of Smad1. Noggin, a BMP receptor blocker, inhibited the laser-induced Runx2 expression and phosphorylation of Smad1. Moreover, laser irradiation significantly increased the calcium content of cell cultures, and noggin inhibited this increase. CONCLUSION: These results suggest that low-intensity laser irradiation stimulates in vitro mineralization via increased expression of BMPs and transcription factors associated with osteoblast differentiation. (c) 2010 Wiley-Liss, Inc.
BACKGROUND: Previously, we reported that low-intensity laser irradiation accelerated bone formation, and that this mechanism deeply involved insulin-like growth factor I expression. However, as bone formation is supported by many local factors, the mechanism involved in laser irradiation remains incompletely understood. Therefore, the purpose of this study was to determine the effects of laser irradiation on the osteogenic response in vitro. METHODS:Mouse osteoblast-like cells, MC3T3-E1, were cultured and were irradiated for 5-20 minutes (0.96-3.82 J/cm(2)) at the subconfluent stage using a low-intensity Ga-Al-As diode laser apparatus. After laser irradiation, expression of bone morphogenetic proteins (BMPs), transcription factors (Runx2, Osterix, Dlx5, Msx2), and phosphorylation of Smad1 were determined, and calcium content of cell cultures was also determined. RESULTS: Irradiation at 1.91 J/cm(2) significantly increased the expression of BMPs and Runx2, Osterix, Dlx5, Msx2, and the phosphorylation of Smad1. Noggin, a BMP receptor blocker, inhibited the laser-induced Runx2 expression and phosphorylation of Smad1. Moreover, laser irradiation significantly increased the calcium content of cell cultures, and noggin inhibited this increase. CONCLUSION: These results suggest that low-intensity laser irradiation stimulates in vitro mineralization via increased expression of BMPs and transcription factors associated with osteoblast differentiation. (c) 2010 Wiley-Liss, Inc.
Authors: M Paschalidou; E Athanasiadou; K Arapostathis; N Kotsanos; P T Koidis; Athina Bakopoulou; Anna Theocharidou Journal: Clin Oral Investig Date: 2019-05-08 Impact factor: 3.573
Authors: Adenilson de Souza da Fonseca; Andre Luiz Mencalha; Vera Maria Araújo de Campos; Samara Cristina Ferreira Machado; Antonio Augusto de Freitas Peregrino; Mauro Geller; Flavia de Paoli Journal: Lasers Med Sci Date: 2012-09-02 Impact factor: 3.161