• Parasites, Hosts and Diseases
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• v.57 no.2
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• pp.145-152
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• 2019

The infection status with Clonorchis sinensis metacercariae (CsMc) was examined in freshwater fishes from Yangcheon (a branch of Gyeongho-gang), which is located in Sancheong-gun, Gyeongsangnam-do, the Republic of Korea. Total 2,201 fishes in 26 species were examined by the artificial digestion method through 7 years. CsMc were detected in 1,171 (53.2%) fishes in 21 spp. (80.8%) and their density was 85 per fish infected. Total 532 (99.6%) out of 534 Pungtungia herzi (index fish) examined were infected with 147 CsMc per fish infected. Metacercarial densities in this fish were highest in 2015 (179 CsMc), followed by 2012 (168), 2013 (152), 2016 (145), 2014 (114), and 2017 (89) respectively. In the gobioninid fish group, i.e., P. herzi, Sarcocheilichthys spp., Squalidus spp., Pseudogobio esocinus, Hemibarbus longirostris, and Hemibarbus labeo, 841 (92.7%) fishes were infected with 117 CsMc per fish infected. Total 250 (54.7%) acheilognathinid fish (bitterlings), Acheilognathus spp. and Acanthorhodeus spp. were infected with 5.8 CsMc. In the rasborinid fish (chubs) group, i.e., Zacco platypus, Zacco temminckii, and Zacco koreanus, 77 (13.7%) out of 563 fish examined were infected with 2.4 CsMc in average. The susceptibility indices of CsMc were 49.09 in the overall positive fish group, 104.15 in the gobioninid group, 3.17 in the acheilognathinid group and 0.35 in the rasborinid fish group respectively. Only 1 CsMc was detected in 3 fish species, Coreoperca herzi, Channa argus, and Lepomis macrochirus, respectively. Conclusively, it was confirmed that CsMc are moderately prevalent in fishes from Yangcheon in Sancheon-gun, Gyeongsangnam-do, Korea.

• Natural Product Sciences
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• v.11 no.3
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• pp.139-144
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• 2005

Bioflavone quercetin is believed to play an important role preventing bone loss by affecting osteoclastogenesis and regulating many systemic and local factors including hormones and cytokines. This study examined how quercetin acts on tumor necrosis factor-alpha ($TNF-{\alpha}$)-mediated apoptosis in MC3T3-E1 osteoblastic cells. Apoptosis assays revealed the dose-dependent acceleration of quercetin on $TNF-{\alpha}-induced$ apoptosis in MC3T3-E1 cells, which was demonstrated by the increased number of positively stained cells in the trypan blue staining and TUNEL assay, and the migration of many cells to the $sub-G_0/G_1$ phase in flow cytometric analysis. In particular, quercetin treatment alone increased the expression of p53 and p21 proteins in the cells. Consequently, this study showed that quercetin accelerates the $TNF-{\alpha}-induced$ apoptosis in MC3T3-E1 osteoblastic cells.

• International Journal of Oral Biology
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• v.39 no.3
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• pp.145-151
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• 2014

During bone remodeling, there is requirement of differentiation of osteoblastic cells. Previously, we identified proteins differentially expressed in soft tissue during bone healing. Of these proteins, we focused the effect of LTF on differentiation of osteoblast. In order to analyze the osteogenic ability of LTF, we treated conditioned media collected from human LTF-stably transfected HEK293T cells into osteoblastic MC3T3-E1. The results showed that the activity and expression of alkaline phosphatase were increased in MC3T3-E1 cells treated with conditioned media containing LTF in dose- and time-dependent manner. At the same time, we observed the significant increase of the expression of osteoblastic genes, such as ALP, BSP, COL1A1, and OCN, and along with matrix mineralization genes, such as DMP1 and DMP2, in LTF conditioned media-treated groups. Moreover, the result of treating recombinant human LTF directly into osteoblastic MC3T3-E1 showed the same pattern of treating conditioned media containing LTF. Our study demonstrated that LTF constitutively enhances osteoblastic differentiation via induction of osteoblastic genes and activation of matrix mineralization in MC3T3-E1 cells.

• BMB Reports
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• v.44 no.10
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• pp.659-664
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• 2011

As part of the search for biologically active anti-osteoporotic agents that enhance differentiation and mineralization of osteoblastic MC3T3-E1 cells, we identified the ginsenoside Rh2(S), which is an active component in ginseng. Rh2(S) stimulates osteoblastic differentiation and mineralization, as manifested by the up-regulation of differentiation markers (alkaline phosphatase and osteogenic genes) and Alizarin Red staining, respectively. Rh2(S) activates p38 mitogen-activated protein kinase (MAPK) in time- and concentration-dependent manners, and Rh2(S)-induced differentiation and mineralization of osteoblastic cells were totally inhibited in the presence of the p38 MAPK inhibitor, SB203580. In addition, pretreatment with Go6976, a protein kinase D (PKD) inhibitor, significantly reversed the Rh2(S)-induced p38 MAPK activation, indicating that PKD might be an upstream kinase for p38 MAPK in MC3T3-E1 cells. Taken together, these results suggest that Rh2(S) induces the differentiation and mineralization of MC3T3-E1 cells through activation of PKD/p38 MAPK signaling pathways, and these findings provide a molecular basis for the osteogenic effect of Rh2(S).

• Nutritional Sciences
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• v.8 no.4
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• pp.242-249
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• 2005

It is well established that zinc plays an important role in bone metabolism and mineralization. The role of zinc in bone formation is well documented in animal models, but not much reported in cell models. In the present study, we evaluated zinc deficiency effects on osteoblastic cell proliferation, alkaline phosphatase activity and expression, and extracellular matrix bone nodule formation and bone-related gene expression in osteoblastic MC3T3-E1 cells. To deplete cellular zinc, chelexed-FBS and interpermeable zinc chelator TPEN were used. MC3T3-E1 cells were cultured in zinc concentration-dependent (0-15 ${\mu}M\;ZnCl_2$) and time-dependent (0-20 days) manners. MC3T3-E1 cell proliferation by MTT assay was increased as medium zinc level increased (p<0.05). Cellular Ca level and alkaline phosphatase activity were increased as medium zinc level increased (p<0.05). Alkaline phosphatase expression, a marker of commitment to the osteoblast lineage, measured by alkaline phosphatase staining was increased as medium zinc level increased. Extracellular calcium deposits measured by von Kossa staining for nodule formation also appeared higher in Zn+(15 ${\mu}M\;ZnCl_2$) than in Zn-(0 ${\mu}M\;ZnCl_2$). Bone formation marker genes, alkaline phosphatase and osteocalcin, were also expressed higher in Zn+ than in Zn-. The current work supports the beneficial effect of zinc on bone mineralization and bone-related gene expression. The results also promote further study as to the molecular mechanism of zinc deficiency for bone formation and thus facilitate to design preventive strategies for zinc-deficient bone diseases.

• Molecules and Cells
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• v.41 no.3
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• pp.234-243
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• 2018

In recent years, the interest towards the relationship between incretins and bone has been increasing. Previous studies have suggested that glucagon-like peptide-1 (GLP-1) and its receptor agonists exert beneficial anabolic influence on skeletal metabolism, such as promoting proliferation and differentiation of osteoblasts via entero-osseous-axis. However, little is known regarding the effects of GLP-1 on osteoblast apoptosis and the underlying mechanisms involved. Thus, in the present study, we investigated the effects of liraglutide, a glucagon-like peptide-1 receptor agonist, on apoptosis of murine MC3T3-E1 osteoblastic cells. We confirmed the presence of GLP-1 receptor (GLP-1R) in MC3T3-E1 cells. Our data demonstrated that liraglutide inhibited the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation, as detected by Annexin V/PI and Hoechst 33258 staining and ELISA assays. Moreover, liraglutide upregulated Bcl-2 expression and downregulated Bax expression and caspase-3 activity at intermediate concentration (100 nM) for maximum effect. Further study suggested that liraglutide stimulated the phosphorylation of AKT and enhanced cAMP level, along with decreased phosphorylation of $GSK3{\beta}$, increased ${\beta}-catenin$ phosphorylation at Ser675 site and upregulated nuclear ${\beta}-catenin$ content and transcriptional activity. Pretreatment of cells with the PI3K inhibitor LY294002, PKA inhibitor H89, and siRNAs GLP-1R, ${\beta}-catenin$ abrogated the liraglutide-induced activation of cAMP, AKT, ${\beta}-catenin$, respectively. In conclusion, these findings illustrate that activation of GLP-1 receptor by liraglutide inhibits the apoptosis of osteoblastic MC3T3-E1 cells induced by serum deprivation through $cAMP/PKA/{\beta}-catenin$ and $PI3K/Akt/GSK3{\beta}$ signaling pathways.

• Restorative Dentistry and Endodontics
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• v.39 no.3
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• pp.187-194
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• 2014

Objectives: The effects of bone morphogenetic protein-2 (BMP-2) and enamel matrix derivative (EMD) respectively with mineral trioxide aggregate (MTA) on hard tissue regeneration have been investigated in previous studies. This study aimed to compare the osteogenic effects of MTA/BMP-2 and MTA/EMD treatment in MC3T3-E1 cells. Materials and Methods: MC3T3-E1 cells were treated with MTA (ProRoot, Dentsply), BMP-2 (R&D Systems), EMD (Emdogain, Straumann) separately and MTA/BMP-2 or MTA/EMD combination. Mineralization was evaluated by staining the calcium deposits with alkaline phosphatase (ALP, Sigma-Aldrich) and Alizarin red (Sigma-Aldrich). The effects on the osteoblast differentiation were evaluated by the expressions of osteogenic markers, including ALP, bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN) and osteonectin (OSN), as determined by reverse-transcription polymerase chain reaction analysis (RT-PCR, AccuPower PCR, Bioneer). Results: Mineralization increased in the BMP-2 and MTA/BMP-2 groups and increased to a lesser extent in the MTA/EMD group but appeared to decrease in the MTA-only group based on Alizarin red staining. ALP expression largely decreased in the EMD and MTA/EMD groups based on ALP staining. In the MTA/BMP-2 group, mRNA expression of OPN on day 3 and BSP and OCN on day 7 significantly increased. In the MTA/EMD group, OSN and OCN gene expression significantly increased on day 7, whereas ALP expression decreased on days 3 and 7 (p < 0.05). Conclusions: These results suggest the MTA/BMP-2 combination promoted more rapid differentiation in MC3T3-E1 cells than did MTA/EMD during the early mineralization period.

• International Journal of Oral Biology
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• v.34 no.1
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• pp.37-42
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• 2009

The attachment and adhesion of RAW 264.7 and MC3T3-E1 cells to titanium (Ti) discs with various degrees of roughness was investigated. The attachment, adhesion, and proliferation of these cells were evaluated after 4 hr, 24 hr and 7 day incubations. Both RAW 264.7 and MC3T3-E1 cells showed a time-dependant correlation between attachment and adhesion on the surface of the titanium discs. Both types of cells tended to have higher survival rate on these discs as the surface roughness increased. The percentage of adherent inflammatory RAW 264.7 cells was greater than MC3T3-E1 cells at 24 hr, but this was reversed at 7 days in culture. The morphology of osteoblastic MC3T3-E1 cells at 24 hr, determined using a surface emission microscope (SEM), appeared flattened and spread out while inflammatory RAW 264.7 cells were predominantly spherical in shape. The adhesion of both cell types on the titanium discs was dependant on the levels of fibronectin adsorbed on the disc surface, indicating that serum constituents modulate the efficient adhesion of these cells. Our data indicate that the cellular response to the titanium surface is dependent on the types of cells, surface roughness and serum constituents.

• International Journal of Oral Biology
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• v.39 no.2
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• pp.121-128
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• 2014

Sambucus sieboldiana (SS) is a member of the family Caprifoliaceae and has been recommended as a functional material because of its several bioactivities. Although numerous literatures are available on the pharmacological and biological activities, the biological activity of SS in bone regeneration process has not yet been well-defined. Therefore, in this study, the effect of SS was investigated in the proliferation and differentiation of MC3T3-E1 osteoblastic cell line. The treatment of SS did not significantly affect the cell proliferation in MC3T3-E1 cells. SS significantly accelerated the mineralization and significantly increased the expression of alkaline phosphatase (ALP) and osteocalcin (OC) mRNAs, compared to the control, in the differentiation of MC3T3-E1 cells. SS significantly accelerated the decrease of osteonectin (ON) mRNA expression as compared with the control in a time-dependent manner in the differentiation of MC3T3-E1 cells. These results suggest that the SS facilitate the osteoblast differentiation and mineralization in MC3T3-E1 osteoblastic cells. Therefore, there may be potential properties for development and clinical application of bone regeneration materials.

• BMB Reports
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• v.33 no.2
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• pp.166-171
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• 2000

Thioredoxin is a multifunctional protein that is ubiquitous in microorganisms, animals and plants. Previously, the expression of the Escherichia coli thioredoxin gene (trxA) was found to be negatively regulated by cAMP. In the present study, the effect of temperature on the expression of the E. coli trxA gene was investigated. In order to examine the temperature effect, the fusion plasmid pCL70 that harbors the E. coli trxA P1P2 promoter was used. The other two fusion plasmids, pJH3 and pMH521 that were constructed in different vectors which harbor the E. coli trxA P2 promoter, were also used. When the E. coli strain MC1061/pCL70 was grown in a rich medium at $25^{\circ}C$, $34^{\circ}C$ and $42^{\circ}C$, the cells grown at $42^{\circ}C$ gave the highest $\beta$-galactosidase activity. The E. coli MC1061/pJH3 and MC1061/pMG521 cells showed increased $\beta$-galactosidase activity after the shift of the culture temperature to $42^{\circ}C$. The wild-type trxA gene of the E. coli MC1061 cells produced much higher thioredoxin activity at the higher temperature. These results support the conclusion that the E. coli trxA gene is regulated in a temperature-dependent manner. Especially the expression from its P2 promoter appeared to be sensitive to temperature.