Background Bone morphogenetic protein (BMP)-2, alkaline phosphatase (ALP), and collagen type I are known to play a critical role in the process of bone remodeling. However, the relationship between mechanical stra...Background Bone morphogenetic protein (BMP)-2, alkaline phosphatase (ALP), and collagen type I are known to play a critical role in the process of bone remodeling. However, the relationship between mechanical strain and the expression of BMP-2, ALP, and COL-I in osteoblasts was still unknown. The purpose of this study was to investigate the effects of different magnitudes of mechanical strain on osteoblast morphology and on the expression of BMP-2, ALP, and COL-I. Methods Osteoblast-like cells were flexed at four deformation rates (0, 6%, 12%, and 18% elongation). The expression of BMP-2 mRNA, ALP, and COL-I in osteoblast-like cells were determined by real-time quantitative reverse transcription polymerase chain reaction, respectively. The results were subjected to analysis of variance (ANOVA) using SPSS 13.0 statistical software. Results The cells changed to fusiform and grew in the direction of the applied strain after the mechanical strain was loaded. Expression level of the BMP-2, ALP, and COL-I increased magnitude-dependently with mechanical loading in the experimental groups, and the 12% elongation group had the highest expression (P 〈0.05). Conclusion Mechanical strain can induce morphological change and a magnitude-dependent increase in the expression of BMP-2, ALP, and COL-I mRNA in osteoblast-like cells, which might influence bone remodeling in orthodontic treatment.展开更多
Objective: To investigate the effects of anastrozole combined with Shuganjiangu decoction on osteoblast-like cells. Methods: Human osteoblast-like cells MG-63 were cultured and divided into four groups control, an...Objective: To investigate the effects of anastrozole combined with Shuganjiangu decoction on osteoblast-like cells. Methods: Human osteoblast-like cells MG-63 were cultured and divided into four groups control, anastrozole, Shuganjiangu decoction (SGJGD), and anastrozole combined with SGJGD. Cell proliferation was investigated by M-IF assay. Alkaline phosphatase (ALP) and osteocalcin, the indicators of cell differentiation, were evaluated by p-nitrophenyl- phosphate method and radioimmunoassay, respectively. Gene expressions of ALP, osteocalcin, osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) were examined by real-time PCR. Results: As evidenced by MTT assay, cell proliferation of MG-63 was inhibited by anastrozole, but stimulated with treatment of SGJGD alone and combined with anastrozole (P〈O.01). Compared with control group, ALP activity was increased by the treatment of SGJGD alone and combined with anastrozole (P〈0.01). Also, osteocalcin secretion was enhanced with the treatment of SGJGD single and combination with anastrozole (P〈O.05). In the real-time PCR assay, gene expressions of ALP and osteocalcin were significantly increased (P〈0.01 for ALP, P〈0.05 for osteocalcin) by the treatment of SGJGD and anastrozole combined with SGJGD, but the expression of RANKL was decreased (P〈O.05). Moreover, anastrozole combined with SGJGD upregulated gene expression of OPG (P〈O.01). Conclusion: SGJGD may alleviate the injury effects of anastrozole on MG-63 cells through adjusting bone formation and resorption indicators.展开更多
There is an increasing interest in phytoestrogens due to their potential medical usage in hormone replacement therapy(HRT). The present study was designed to investigate the in vitro effects of estrogen-like activitie...There is an increasing interest in phytoestrogens due to their potential medical usage in hormone replacement therapy(HRT). The present study was designed to investigate the in vitro effects of estrogen-like activities of two widespread coumarins, osthole and imperatorin, using the MCF-7 cell proliferation assay and their alkaline phosphatase(ALP) activities in osteoblasts Saos-2 cells. The two compounds were found to strongly stimulate the proliferation of MCF-7 cells. The estrogen receptor-regulated ERα, progesterone receptor(PR) and PS2 m RNA levels were increased by treatment with osthole and imperatorin. All these effects were significantly inhibited by the specific estrogen receptor antagonist ICI182, 780. Cell cycle analysis revealed that their proliferation stimulatory effect was associated with a marked increase in the number of MCF-7 cells in S phase, which was similar to that observed with estradiol. It was also observed that they significantly increased ALP activity, which was reversed by ICI182,780. These results suggested that osthole and imperatorin could stimulate osteoblastic activity by displaying estrogenic properties or through the ER pathway. In conclusion, osthole and imperatorin may represent new pharmacological tools for the treatment of osteoporosis.展开更多
文摘Background Bone morphogenetic protein (BMP)-2, alkaline phosphatase (ALP), and collagen type I are known to play a critical role in the process of bone remodeling. However, the relationship between mechanical strain and the expression of BMP-2, ALP, and COL-I in osteoblasts was still unknown. The purpose of this study was to investigate the effects of different magnitudes of mechanical strain on osteoblast morphology and on the expression of BMP-2, ALP, and COL-I. Methods Osteoblast-like cells were flexed at four deformation rates (0, 6%, 12%, and 18% elongation). The expression of BMP-2 mRNA, ALP, and COL-I in osteoblast-like cells were determined by real-time quantitative reverse transcription polymerase chain reaction, respectively. The results were subjected to analysis of variance (ANOVA) using SPSS 13.0 statistical software. Results The cells changed to fusiform and grew in the direction of the applied strain after the mechanical strain was loaded. Expression level of the BMP-2, ALP, and COL-I increased magnitude-dependently with mechanical loading in the experimental groups, and the 12% elongation group had the highest expression (P 〈0.05). Conclusion Mechanical strain can induce morphological change and a magnitude-dependent increase in the expression of BMP-2, ALP, and COL-I mRNA in osteoblast-like cells, which might influence bone remodeling in orthodontic treatment.
基金supported by the grant of Key Program Foundation of Beijing TCMs Administration(2004-IV15),China
文摘Objective: To investigate the effects of anastrozole combined with Shuganjiangu decoction on osteoblast-like cells. Methods: Human osteoblast-like cells MG-63 were cultured and divided into four groups control, anastrozole, Shuganjiangu decoction (SGJGD), and anastrozole combined with SGJGD. Cell proliferation was investigated by M-IF assay. Alkaline phosphatase (ALP) and osteocalcin, the indicators of cell differentiation, were evaluated by p-nitrophenyl- phosphate method and radioimmunoassay, respectively. Gene expressions of ALP, osteocalcin, osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) were examined by real-time PCR. Results: As evidenced by MTT assay, cell proliferation of MG-63 was inhibited by anastrozole, but stimulated with treatment of SGJGD alone and combined with anastrozole (P〈O.01). Compared with control group, ALP activity was increased by the treatment of SGJGD alone and combined with anastrozole (P〈0.01). Also, osteocalcin secretion was enhanced with the treatment of SGJGD single and combination with anastrozole (P〈O.05). In the real-time PCR assay, gene expressions of ALP and osteocalcin were significantly increased (P〈0.01 for ALP, P〈0.05 for osteocalcin) by the treatment of SGJGD and anastrozole combined with SGJGD, but the expression of RANKL was decreased (P〈O.05). Moreover, anastrozole combined with SGJGD upregulated gene expression of OPG (P〈O.01). Conclusion: SGJGD may alleviate the injury effects of anastrozole on MG-63 cells through adjusting bone formation and resorption indicators.
基金supported by the National Natural Science Foundation of China(No.81202865)
文摘There is an increasing interest in phytoestrogens due to their potential medical usage in hormone replacement therapy(HRT). The present study was designed to investigate the in vitro effects of estrogen-like activities of two widespread coumarins, osthole and imperatorin, using the MCF-7 cell proliferation assay and their alkaline phosphatase(ALP) activities in osteoblasts Saos-2 cells. The two compounds were found to strongly stimulate the proliferation of MCF-7 cells. The estrogen receptor-regulated ERα, progesterone receptor(PR) and PS2 m RNA levels were increased by treatment with osthole and imperatorin. All these effects were significantly inhibited by the specific estrogen receptor antagonist ICI182, 780. Cell cycle analysis revealed that their proliferation stimulatory effect was associated with a marked increase in the number of MCF-7 cells in S phase, which was similar to that observed with estradiol. It was also observed that they significantly increased ALP activity, which was reversed by ICI182,780. These results suggested that osthole and imperatorin could stimulate osteoblastic activity by displaying estrogenic properties or through the ER pathway. In conclusion, osthole and imperatorin may represent new pharmacological tools for the treatment of osteoporosis.