Glycyrrhiza uralensis (licorice) extracts increase cell proliferation and bone marker enzyme alkaline phosphatase activity in osteoblastic MC3T3-E1 cells / 한국영양학회지

PURPOSE: The Glycyrrhiza uralensis species (Leguminosae) as a medicinal biocompound, and one of its root components, isoliquritigenin (ISL), which is a flavonoid, has been reported to have anti-tumor activity in vitro and in vivo. However, its function in bone formation has not been studied yet. In this study, we tested the effect of Glycyrrhiza uralensis (ErLR) and baked Glycyrrhiza uralensis (EdLR) extracts on osteoblast proliferation, alkaline phosphatase (ALP) activity, and bone-related gene expression in osteoblastic MC3T3-E1 cells. METHODS: MC3T3-E1 cells were cultured in various levels of ErLR (0, 5, 10, 15, 20 µg/mL), EdLR (0, 5, 10, 15, 20 µg/mL), or ISL (0, 5, 10, 15, 20 µM) in time sequences (1, 5, and 20 days). Also, isoliquritigenin (ISL) was tested for comparison to those two biocompound extracts. RESULTS: MTT assay results showed that all three compounds (ErLR, EdLR, and ISL) increased osteoblastic-cell proliferation in a concentration-dependent manner for one day. In addition, both ErLR and EdLR compounds elevated the osteoblast proliferation for 5 or 20 days. Extracellular ALP activity was also increased as ErLR, EdLR, and ISL concentration increased at 20 days, which implies the positive effect of Glycyrrhiza species on osteoblast mineralization. The bone-related marker mRNAs were upregulated in the ErLR-treated osteoblastic MC3T3-E1 cells for 20 days. Bone-specific transcription factor Runx2 gene expression was also elevated in the ErLR- and EdLR-treated osteoblastic MC3T3-E1 cells for 20 days. CONCLUSION: These results demonstrated that Glycyrrhiza uralensis extracts may be useful for preventing osteoporosis by increasing cell proliferation, ALP activity, and bone-marker gene expression in osteoblastic cells.

Comparison of alkaline phosphatase activity of MC3T3-E1 cells cultured on different Ti surfaces: modified sandblasted with large grit and acid-etched (MSLA), laser-treated, and laser and acid-treated Ti surfaces

PURPOSE: In this study, the aim of this study was to evaluate the effect of implant surface treatment on cell differentiation of osteoblast cells. For this purpose, three surfaces were compared: (1) a modified SLA (MSLA: sand-blasted with large grit, acid-etched, and immersed in 0.9% NaCl), (2) a laser treatment (LT: laser treatment) titanium surface and (3) a laser and acid-treated (LAT: laser treatment, acid-etched) titanium surface. MATERIALS AND METHODS: The MSLA surfaces were considered as the control group, and LT and LAT surfaces as test groups. Alkaline phosphatase expression (ALP) was used to quantify osteoblastic differentiation of MC3T3-E1 cell. Surface roughness was evaluated by a contact profilometer (URFPAK-SV; Mitutoyo, Kawasaki, Japan) and characterized by two parameters: mean roughness (Ra) and maximum peak-to-valley height (Rt). RESULTS: Scanning electron microscope revealed that MSLA (control group) surface was not as rough as LT, LAT surface (test groups). Alkaline phosphatase expression, the measure of osteoblastic differentiation, and total ALP expression by surface-adherent cells were found to be highest at 21 days for all three surfaces tested (P.05). CONCLUSION: This study suggested that MSLA and LAT surfaces exhibited more favorable environment for osteoblast differentiation when compared with LT surface, the results that are important for implant surface modification studies.

Effect of 1, 25-dihydroxy vitamin D3 combined with mechanical strain treatment on proliferation, differentiation, and expression of OPG and RANKL in osteoblastic MC3T3-E1 cells / 医用生物力学

Objective To investigate the effect of 1,25-(OH)2-vitamin D3 (VD3) or mechanical strain alone and their combined treatment on proliferation and differentiation of pre-osteoblast MC3T3-E1 cells in vitro, as well as gene and protein expression of osteoprotegerin (OPG) and receptor activator of nuclear factor-кB ligand (RANKL) in those cells. Methods MC3T3-E1 cells were treated with 10 nmol/L VD3, intermitted mechanical strain or with a combination of these two factors. Cell proliferation was assessed with flow cytometry, and alkaline phosphatase (ALP) activity was measured using a fluorometric detection kit. The mRNA expression of ALP, runt-related transcriptional factor 2 (Runx2), OPG, and RANKL genes was determined by real-time PCR. The proteins expression of Runx2, OPG, and RANKL was determined by Western blotting. ResultsVD3 inhibited the proliferation of MC3T3-E1 cells, but the mechanical strain had no effect on cell proliferation. Mechanical strain, VD3, and the combined treatment enhanced the ALP activity of MC3T3-E1 cells as well as the protein expression of Runx2. The effect of combined treatment was less pronounced than the effect of VD3 or mechanical strain alone. Mechanical strain promoted the gene and protein expression of osteoprotegerin (OPG) and increased the ratio of OPG/RANKL. However, the combination of VD3 and mechanical strain led to a decrease in ratio of OPG/RANKL. Conclusions Mechanical strain might be effective in inducing osteogenic differentiation and increasing bone formation. A joint stimulation with VD3 and strain can decrease proliferation and osteogenic differentiation and increase RANKL expression, which might affect bone remodeling. This study supplies some new data, which might be important in theoretical and clinical research of osteoporosis (OP) and other related bone diseases.

Zinc may increase bone formation through stimulating cell proliferation, alkaline phosphatase activity and collagen synthesis in osteoblastic MC3T3-E1 cells

Zinc is an essential trace element required for bone formation, however not much has been clarified yet for its role in osteoblast. We hypothesized that zinc would increase osteogenetic function in osteoblasts. To test this, we investigated whether zinc treatment enhances bone formation by stimulating osteoblast proliferation, bone marker protein alkaline phosphatase activity and collagen synthesis in osteoblastic MC3T3-E1 cells. MC3T3-E1 cells were cultured and treated with various concentrations of zinc (0, 1, 3, 15, 25 uM) along with a normal osteogenic medium (OSM) as control for 1, 5, 10 days. As measured by MTT assay for mitochondrial metabolic activity, cell proliferation was stimulated even at low zinc treatment (1-3 micrometer) compared to OSM, and it was stimulated in a zinc concentration-dependent manner during 5 and 10 days, with the most pronounced effect at 15 and 25 uM Zn. Cellular (synthesized) alkaline phosphatase (ALP) activity was increased in a zinc concentration-dependent manner, so did medium (secreted) ALP activity. Cellular collagen concentration was increased by zinc as time went by, therefore with the maximum zinc stimulatory effect in 10 days, and medium collagen concentration showed the same pattern even on 1 and 5 day. This zinc stimulatory effect of collagen synthesis was observed in cell matrix collagen staining. The study results imply that zinc can increase osteogenic effect by stimulating cell proliferation, ALP activity and collagen synthesis in osteoblastic cells.

A bioactivity study of Portland cement mixed with beta-glycerophosphosphate on human pulp cell / 대한치과보존학회지

The purpose of this study is to investigate the response of human pulp cell on Portland cement mixed with beta-glycerophosphate. To investigate the effect of beta-glycerophosphate and/or dexamethasone on human pulp cell, ALP activity on various concentration of beta-glycerophosphate and dexamethasone was measured and mineral nodule of human pulp cell was stained with Alizarin red S. MTS assay and ALP activity of human pulp cell on Portland cement mixed with various concentration of beta-glycerophosphate (10 mM, 100mM, 1M) was measured and the specimens were examined under SEM. Addition of beta-glycerophosphate or dexamethasone alone had no effect however, the addition of 5 mM beta-glycerophosphate and 100 nM dexamethasone had the largest increasement in ALP activity. There was no toxicity in all samples and the data showed that Portland cement mixed with 10 mM beta-glycerophosphate had more increase in ALP activity compared with control. In conclusion, Portland cement mixed with beta-glycerophosphate has no toxicity and promotes differentiation and mineralization of pulp cell compared with additive-free Portland cement. This implicated that application of Portland cement mixed with beta-glycerophosphate might form more reparative dentin and in turn it would bring direct pulp capping to success.

The Effects of Calcium Phosphate Glass on Mouse Calvarial Cell / 대한치주과학회지

The goal of periodontal treatment is not only to arrest the progression of the disease but also to promote the functional, esthetic regeneration of the periodontium. Flap operation, bone graft, guided tissue regeneration, growth factors and bone morphogenetic protein have been used for this purpose. Among these techniques of regeneration, alloplastic graft, especially calcium phosphate is getting more attention recently. The purpose of this study was to evaluate the effects of calcium phosphate glass on mouse calvarial cell in vitro. The toxicity of calcium phosphate glass was measured using MTT assay, the synthesis of collagen was measured using collagen assay, and ALP activity was measured. The experimental groups were cultured with calcium phosphate glass(both AQ-, and HT-CPG) in concentration of 0.01, 0.02, 0.1, 0.2g/ml. The results are as follows 1. In concentrations not exceeding 0.02g/ml, both the groups(AQ-CPG, HT-CPG) didn't show any toxicity on mouse calvarial cell(p<0.05). 2. In both the experimental groups are the concentration of 0.02g/ml, collagen expressions were significantly up-regulated (p<0.05). 3. In both the experimental groups are the concentration of 0.02g/ml, ALP activity was not significantly upregulated, but ALP activity in both experimental groups were greater than control group(p<0.05). The results suggested that the use of calcium phosphate glass may promotes periodontal regeneration. Ongoing studies are necessary in order to determine their regeneration effects.

Effects of Nicotine on mineralization in human fetal osteoblasts / 대한치주과학회지

Nicotine is one of the major components of cigarette smoking which causes various systemic and local diseases to human body. The purpose of the present study was to investigate the effects of nicotine on bone mineralization in human fetal osteoblasts cell line(hFOB1). To compare the alkaline ph-osphatase(ALP) synthesis, hFOB1 were cultured with DMEM/F-12 1:1 Mixture and 100 pg/ml, 1 ng/ml, 10 ng/ml, 100 ng/ml, 1 microgram/ml, 10 microgram/ml, 100 microgram/ml of nicotine. And to compare the calcium accumulation, hFOB1 cultured for 23 days were quantified and photographed. ALP activity of hFOB1 exposed to nicotine was not significantly changed at a lower concentrations of nicotine, but was significantly decreased at a higher concentrations (10 microgram/ml, 100 microgram/ml) of nicotine (p<0.05). A quantified calcium acculation in hFOB1 was significantly decreased at 1, 10, and 100microgram/ml of nicotine (p<0.05). Significantly decreased calcium deposition was observed at 1, 10, and 100microgram/ml of nicotine. These results indicate that a higher concentration of nicotine show a negative effects on mineralization of hFOB1.

The biological effects of fibronectin typeIII 7-10 to MC3T3-E1 osteoblast / 대한치주과학회지

No abstract available.

The effects of chitosan on the human periodontal ligament fibroblasts in vitro / 대한치주과학회지

Periodontal therapy has dealt primarily with attempts at arresting progression of disease, however, more recent techniques have focused on regenerating the periodontal ligament having the capacity to regenerate the periodontium. The effect of chitosan(poly-N-acetyl glucosaminoglycan), a carbohydrate biopolymer extracted from chitin, on periodontal ligament regeneration is of particular interest. The purpose of this study was to evaluate the effect of chitosan on the human periodontal ligament fibroblasts(hPDLFs) in vitro, with special focus on their proliferative properties by MTT assay, the synthesis of type I collagen by reverse transcription-polymerase chain reaction(RT-PCR) and the activity of alkaline phosphatase(ALP). Fibroblast populations were obtained from individuals with a healthy periodontium and cultured with alpha-MEM as the control group. The experimental groups were cultured with chitosan in concentration of 0.01, 0.1, 1, 2mg/ml. The results are as follows; 1. Chitosan-induced proliferative responses of hPDLFs reached a plateau at the concentration of 0.1mg/ml (p<0.05). 2. When hPDLFs were stimulated with 0.1mg/ml chitosan, mRNA expression of type I collagen was up-regulated. 3. When hPDLFs were stimulated with 0.1mg/ml chitosan, ALP activity was significantly upregulated(p<0.05). In summary, chitosan(0.1mg/ml) enhanced the type I collagen synthesis in the early stage, and afterwards, facilitated differentiation into osteogenic cells. The results of this in vitro experiment suggest that chitosan potentiates the differentiation of osteoprogenitor cells and may facilitate the formation of bone.

Effect of Inorganic Polyphosphate on Cultured Periodontal Ligament Cells / 체질인류학회지

This study was designed to examine the effect of polyP on the periodontal ligament fibroblasts. The cells were incubated for 24 and 48 hours with various concentrations (0.001%, 0.002%, 0.005%, 0.010%, 0.020%, 0.040%) of polyP. Cell activity, alkaline phosphatase activity, and protein synthesis activity of the cells were examined. The results were as follows: 1. Twenty four hours after incubation with polyP, the cell activity of the periodontal ligament fibroblasts was increased. Forty eight hours after polyP application, the activity of the cells was similar to that of control group. 2. Twenty four or forty eight hours after incubation with polyP, the alkaline phosphatase activity of the periodontal ligament fibroblasts was increased. 3. The protein synthesis of the periodontal ligament fibroblasts was not changed after polyP application. These results suggest that, polyP may increase the cell activity and alkaline phosphatase activity of periodotal ligament fibroblasts and polyP may not affect the protein synthesis of the cells.

The effect of a static magnetic field on the bone nodule formation of MC3T3-E1 cells / 대한치과교정학회지

To evaluate the effect of a static magnetic field on the bone producing potential of MC3T3 El cells, the alkaline phosphatase activity was measured after the cells having been cultured under 76.4mT static magnetic field using a SmCos magnets for 5days, 7days, lldays, 15days and 2ldays for each cell culture group. Also, the amount of bone nodule stained with Alizarin red S was observed. The results were as follows. · The alkaline phosphatase activity of the 7, 11, and 15 days group among the experimental groups was decreased as compared with the control groups, and the decrease of alkaline phosphatase activity in the 11 days group was the most evident among them. · Any stained bone nodules of both groups had not been observed until the 11th day. The stained bone nodules in the control groups were found on the 15th day, but not in the experimental groups. The stained bone nodules were observed in both groups on the 21st day, but the control groups have more bone nodules than the experimental groups.

The effects of continuous and intermittent compressive pressure on alkaline phosphatase activity of MC3T3-E1 cells / 대한치과교정학회지

The propose of this study was to evaluate the difference of cellular activity dependent on intermittent compressive force by determining the alkaline phosphatase activity. Alkaline phosphatase activity was measured on control and experimental groups every 24, 48, 72hours. Experimental groups consisted of continous and intermittent compressive group which were compressed by 300g/cm2 of diaphram pump. The intermittent compressive group was connected by timer which was worked on 10 minutes an off 10 minutes. The results were as follows; 1. The alkaline phosphatase activity between control and experimental groups showed not significant difference at compressed 24 hours. 2. The alkaline phosphatase activity of experimental groups were more increased than control group at compressed 48 hours. 3. The alkaline phosphatase activity of intermittent compressive group showed significant increased to control group. Whereby continuous compressive group showed not significant difference to control at 72 hours. 4. The alkaline phosphatase activity of intermittent compressive group were stringly increased than continuous compressive groups. 5. Between experimental groups and control group no other morphologic changes were detected by microscopic findings.