• 대한치과교정학회지
• /
• 제27권2호
• /
• pp.335-347
• /
• 1997

교정치료시 치아이동은 치주인대세포를 매개로 골조직의 개조가 일어나는 과정으로서 골조직의 성장과 개조는 조골세포, 파골세포 및 그 전구세포의 증식, 분화 및 활성에 영향을 미치는 여러가지 전신적 인자와 국소적 인자에 의하여 조절되고 있다. 1.25-Dihydroxyvitamin $D_3$는 vitamin $D_3$의 대사물로서 경조직에 있어서 칼슘과 인산의 이동에 중요한 역할을 담당하고 있는 것으로 알려져 있으나 치주인대에 대한 1,25-Dihydroxyvitamin $D_3$의 생물학적 기능은 잘 알려져 있지 않다. 1.25-Dihydroxyvitamin $D_3$가 치주인대세포의 활성에 미치는 영향을 관찰하고자 10, 25, 50, 100ng/ml농도의 1,25 Dihydroxyvitamin $D_3$를 배양 치주인대세포에 첨가하여 배양 1, 2, 3일 후 M.T.T. 방법으로 세포의 활성을 관찰하였으며, 백서의 실험적 치아이동시 치주인대 내에 1,25-Dihydroxyvitamin $D_3$를 투여하여 12, 24, 36, 48, 72시간 및 7일 후의 조직 변화 소견을 관찰하여 다음과 같은 결과를 얻었다. 1. 10ng, 25ng/ml 농도의 1,25-Dihydroxyvitamin $D_3$를 치주인대세포에 가한 후 배양 1, 2, 3일째의 실험군 활성은 대조군과 차이가 없었다. 2. 50ng/ml 농도의 1,25-Dihydroxyvitamin $D_3$를 치주인대세포에 가한 후 배양 3일째의 활성은 대조군에 비하여 유의하게 증가되었으며 100ng/ml농도에서는 배양 2, 3일째에 유의하게 많았다. 3. 백서에 교정력을 가한 후 인장측에서의 골아세포 활성, 치주인대섬유의 파열, 모세혈관 증식은 투여후 7일까지 1.25-Dihydroxyvitamin $D_3$ 투여측과 대조측 간에 차이가 없었다. 4. 교정력을 가한 후 36시간부터 1,25-Dihydroxyvitamin $D_3$를 투여한 압박측의 파골세포 활성 및 치조골 흡수량이 증가하였다. 이상과 같은 결과로, 50-100ng/ml 농도에서 1,25-Dihydroxyvitamin $D_3$의 농도와 배양 기간에 비례하여 치주인대세포의 활성이 증가하였으며 1,25-Dihydroxyvitarnin $D_3$가 투여 36시간부터 파골세포의 활성과 그에 따른 치조골 흡수량 증가에 영향을 미쳤다고 사료된다.

• Restorative Dentistry and Endodontics
• /
• 제41권4호
• /
• pp.296-303
• /
• 2016

Objectives: The purpose of the present study was to evaluate the effects of proanthocyanidin (PAC), a crosslinking agent, on the physical properties of a collagen hydrogel and the behavior of human periodontal ligament cells (hPDLCs) cultured in the scaffold. Materials and Methods: Viability of hPDLCs treated with PAC was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The physical properties of PAC treated collagen hydrogel scaffold were evaluated by the measurement of setting time, surface roughness, and differential scanning calorimetry (DSC). The behavior of the hPDLCs in the collagen scaffold was evaluated by cell morphology observation and cell numbers counting. Results: The setting time of the collagen scaffold was shortened in the presence of PAC (p < 0.05). The surface roughness of the PAC-treated collagen was higher compared to the untreated control group (p < 0.05). The thermogram of the crosslinked collagen exhibited a higher endothermic peak compared to the uncrosslinked one. Cells in the PAC-treated collagen were observed to attach in closer proximity to one another with more cytoplasmic extensions compared to cells in the untreated control group. The number of cells cultured in the PAC-treated collagen scaffolds was significantly increased compared to the untreated control (p < 0.05). Conclusions: Our results showed that PAC enhanced the physical properties of the collagen scaffold. Furthermore, the proliferation of hPDLCs cultured in the collagen scaffold crosslinked with PAC was facilitated. Conclusively, the application of PAC to the collagen scaffold may be beneficial for engineering-based periodontal ligament regeneration in delayed replantation.

• Journal of Periodontal and Implant Science
• /
• 제51권5호
• /
• pp.329-341
• /
• 2021

Purpose: Periodontal treatment aims at complete regeneration of the periodontium, and developing strategies for periodontal regeneration requires a deep understanding of the tissues composing the periodontium. In the present study, the stemness characteristics and gene expression profiles of cementum-derived cells (CDCs) were investigated and compared with previously established human stem cells. Candidate marker proteins for CDCs were also explored. Methods: Periodontal ligament stem cells (PDLSCs), pulp stem cells (PULPSCs), and CDCs were isolated and cultured from extracted human mandibular third molars. Human bone marrow stem cells (BMSCs) were used as a positive control. To identify the stemness of CDCs, cell differentiation (osteogenic, adipogenic, and chondrogenic) and surface antigens were evaluated through flow cytometry. The expression of cementum protein 1 (CEMP1) and cementum attachment protein (CAP) was investigated to explore marker proteins for CDCs through reverse-transcription polymerase chain reaction. To compare the gene expression profiles of the 4 cell types, mRNA and miRNA microarray analysis of 10 samples of BMSCs (n=1), PDLSCs (n=3), PULPSCs (n=3), and CDCs (n=3) were performed. Results: The expression of mesenchymal stem cell markers with a concomitant absence of hematopoietic markers was observed in PDLSCs, PULPSCs, CDCs and BMSCs. All 4 cell populations also showed differentiation into osteogenic, adipogenic, and chondrogenic lineages. CEMP1 was strongly expressed in CDCs, while it was weakly detected in the other 3 cell populations. Meanwhile, CAP was not found in any of the 4 cell populations. The mRNA and miRNA microarray analysis showed that 14 mRNA genes and 4 miRNA genes were differentially expressed in CDCs vs. PDLSCs and PULPSCs. Conclusions: Within the limitations of the study, CDCs seem to have stemness and preferentially express CEMP1. Moreover, there were several up- or down-regulated genes in CDCs vs. PDLSCs, PULPSCs, and BMSCs and these genes could be candidate marker proteins of CDCs.

• Restorative Dentistry and Endodontics
• /
• 제34권5호
• /
• pp.430-441
• /
• 2009

본 연구는 사람 치수세포 및 치주인대세포의 차이를 알아보고자 배양한 각각의 세포를 CDNA microarray assay를 통하여 유전자의 발현정도의 차이를 비교하였다. 그 결과를 바탕으로 각각의 세포에서 2배 이상의 유전자 발현의 차이를 보이는 유전자중 특징적인 3가지 유전자를 선택하여 RT-PCR로 검증한 결과 다음과 같은 결론을 얻었다; 1. Microarray assay 결과, 치주인대 세포에 비해 치수 세포에서 2배 이상 발현한 유전자 수는 총 51개가 나타났다. 2. RT-PCR의 결과, 치주인대세포에 비해 치수 세포에서 ITGA4, TGF-${\beta}2$ 등이 높게 나타났다. 3. Microarray assay결과, 치수 세포에서 비해 치주인대 세포에서 2배 이상 발현한 유전자 수는 총 19개가 나타났다. 4. RT-PCR의 결과, 치수 세포에 비해 치주인대세포에서 LUM, WISP1, MMP1 등이 높게 나타났다. 본 연구 결과로 치수세포에는 상아질 형성에 관여하는 특징적인 유전자가 치주인대세포에 비해 높게 발현되었으며, 치주인대세포에는 교원질 합성에 관여하는 특징적인 유전자가 치수세포에 비해 높게 발현되어, 치수세포와 치주인데 세포는 유전자 발현의 차이가 나타남을 알 수 있었다.

• Journal of Periodontal and Implant Science
• /
• 제47권5호
• /
• pp.273-291
• /
• 2017

Purpose: Although static magnetic fields (SMFs) have been used in dental prostheses and osseointegrated implants, their biological effects on osteoblastic and cementoblastic differentiation in cells involved in periodontal regeneration remain unknown. This study was undertaken to investigate the effects of SMFs (15 mT) on the osteoblastic and cementoblastic differentiation of human osteoblasts, periodontal ligament cells (PDLCs), and cementoblasts, and to explore the possible mechanisms underlying these effects. Methods: Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity, mineralized nodule formation based on Alizarin red staining, calcium content, and the expression of marker mRNAs assessed by reverse transcription polymerase chain reaction (RT-PCR). Signaling pathways were analyzed by western blotting and immunocytochemistry. Results: The activities of the early marker ALP and the late markers matrix mineralization and calcium content, as well as osteoblast- and cementoblast-specific gene expression in osteoblasts, PDLCs, and cementoblasts were enhanced. SMFs upregulated the expression of Wnt proteins, and increased the phosphorylation of glycogen synthase $kinase-3{\beta}$ ($GSK-3{\beta}$) and total ${\beta}-catenin$ protein expression. Furthermore, p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase (MAPK), and nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) pathways were activated. Conclusions: SMF treatment enhanced osteoblastic and/or cementoblastic differentiation in osteoblasts, cementoblasts, and PDLCs. These findings provide a molecular basis for the beneficial osteogenic and/or cementogenic effect of SMFs, which could have potential in stimulating bone or cementum formation during bone regeneration and in patients with periodontal disease.

• Journal of Periodontal and Implant Science
• /
• 제32권4호
• /
• pp.733-744
• /
• 2002

The fibroblasts are the principal cells in the periodontal ligament of peridontium. As the periodontal ligament fibroblasts (PDLF) show similar phenotype with osteoblasts, the PDLF are thought to play an important role in alveolar bone remodeling. Cell-to-cell contacted signaling is crucial for osteoclast formation. Recently it has been reported that PDLJ enhance the bone resorbing activity of osteoclasts differentiated from hematopoietic preosteoclasts. The aims of this study were to $clarify\;^{1)}$ the mechanism of PDLF-induced osteoclastogenesis $and\;^{2)}$ whether we can use preosteoclast cell line instead of primary hematopoietic preosteoclast cells for studying the mechanism of PDLF-induced osteoclastogenesis. Osteoclastic differentiation of mouse macrophage cell line RAW264.7 was compared with that of mouse bone marrow-derived M-CSF dependent cell (MDBM), a well-known hematopoietic preosteoclast model, by examining, 1) osteoclast-specific gene expression such as calcitonin receptor, M-CSF receptor (c-fms), cathepsin K, receptoractivator nuclear factor kappa B (RANK) ,2) generation of TRAP(+) multinucleated cells (MNCs), and 3) generation of resorption pit on the $OAAS^{TM}$ plate. RAW264.7 cultured in the medium containing of soluble osteoclast differentiation Factor (sODF) showed similar phenotype with MDBM-derived osteoclasts, those are mRNA expression pattern of osteoclast-specific genes, TRAP(+) MNCs generation, and bone resorbing abivity. Formation of resorption pits by osteoclastic MNCs differentiated from sODF-treated RAW264.7, was completely blocked by the addition of osteoprotegerin (OPG), a soluble decoy receptor for ODF, to the sODF-containing culture me야um. The effects of PDLF on differentiation of RAW264.7 into　the TRAP(+) multinucleated osteoclast-like cells were examined using coculture system. PDLF were fxed with paraformaldehyde, followed by coculture with RAW264.7, which induced formation of TRAP(+) MNCs in the absence of additional treatment of sODF. When compared with untreated and fixed PDLF (fPDLF), IL-1 ${\beta}$-treated, or lipopolysaccha-ride-treated and then fixed PDLF showed two-folld increase in the supporting activity of osteoclastogenesis from RAW264.7 coculture system. There were no TRAP(+) MNCs formation in coculture system of RAW264.7 with PDLF of no fixation. These findigs suggested that we can replace the primary hematopoietic preosteoclasts for RAW264. 7 cell line for studying the mechanism of PDLF-induced osteoclastogenesis, and we hypothesize that PDLF control osteoclastogenesis through ODF expression which might be enhanced by inflammatory signals.

• BMB Reports
• /
• 제42권7호
• /
• pp.427-432
• /
• 2009

Orthodontic tooth movement results from the combinational process of both bone resorption and formation in the compressive and tension sides, respectively. However, the genes responsible for new bone formation in tension sides have not been determined. In this study, we used DNA microarray and real-time RT-PCR to identify genes in human periodontal ligament (PDL) cells that undergo significant changes in expression in response to static tensional forces (2 or 12 hours). The genes found were alkaline phospatase (ALP), matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), and several collagen genes. Furthermore, an ELISA evaluating the expression of VEGF, type IV collagen and MMP-2 found levels significantly increased after 24 and 72 hours (P < 0.05). ALP activity was also increased after 24 hours (P < 0.05). Collectively, we found the genes up-regulated in our study by the static tensional force are related to osteogenic processes such as matrix synthesis and angiogenesis.

• Journal of Periodontal and Implant Science
• /
• 제41권3호
• /
• pp.149-156
• /
• 2011

Purpose: Globular adiponectin (gAd) is a type of adipocytokine, which is mainly produced by adipose tissue. It has been reported that gAd acts as a pro- as well as an anti-inflammatory factor. Interleukin (IL)-6 and IL-8 are pro-inflammatory cytokines. To investigate the role of gAd on periodontal tissues, the expression of adiponectin receptor 1 (AdipoR1) and the effect of gAd on the expression of IL-6 and IL-8 were investigated in periodontal ligament (PDL) and gingival fibroblasts. Methods: PDL and gingival fibroblasts were cultured from human periodontal tissues. gAd derived from Escherichia coli and murine myeloma cells were used. The expression of AdipoR1 was estimated by reverse transcription-polymerase chain reaction and western blot The expression of cytokines was measured by enzyme-linked immunosorbent assay. Results: PDL and gingival fibroblasts expressed both mRNA and protein of AdipoR1. gAd derived from E. coli increased the production of IL-6 and IL-8, but polymyxin B, an inhibitor of lipopolysaccharide (LPS), inhibited IL-6 and IL-8 production induced by gAd in both types of cells. gAd derived from murine myeloma cells did not induce IL-6 and IL-8 production in those cells. gAd derived from E. coli contained higher levels of LPS than gAd derived from murine myeloma cells. LPS increased production of IL-6 and IL-8 in PDL and gingival fibroblasts, but pretreatment of cells with gAd derived from murine myeloma cells did not inhibit LPS-induced IL-6 and IL-8 expression. Conclusions: Our results suggest that PDL and gingival fibroblasts express AdipoR1 and that gAd does not act as a modulator of IL-6 and IL-8 expression in PDL and gingival fibroblasts.

• Journal of Periodontal and Implant Science
• /
• 제40권3호
• /
• pp.105-110
• /
• 2010

Purpose: It has been reported that low-level semiconductor diode lasers could enhance the wound healing process. The periodontal ligament is crucial for maintaining the tooth and surrounding tissues in periodontal wound healing. While low-level semiconductor diode lasers have been used in low-level laser therapy, there have been few reports on their effects on periodontal ligament fibroblasts (PDLFs). We performed this study to investigate the biological effects of semiconductor diode lasers on human PDLFs. Methods: Human PDLFs were cultured and irradiated with a gallium-aluminum-arsenate (GaAlAs) semiconductor diode laser of which the wavelength was 810 nm. The power output was fixed at 500 mW in the continuous wave mode with various energy fluencies, which were 1.97, 3.94, and 5.91 $J/cm^2$. A culture of PDLFs without laser irradiation was regarded as a control. Then, cells were additionally incubated in 72 hours for MTS assay and an alkaline phosphatase (ALPase) activity test. At 48 hours post-laser irradiation, western blot analysis was performed to determine extracellular signal-regulated kinase (ERK) activity. ANOVA was used to assess the significance level of the differences among groups (P<0.05). Results: At all energy fluencies of laser irradiation, PDLFs proliferation gradually increased for 72 hours without any significant differences compared with the control over the entire period taken together. However, an increment of cell proliferation significantly greater than in the control occurred between 24 and 48 hours at laser irradiation settings of 1.97 and 3.94 $J/cm^2$ (P<0.05). The highest ALPase activity was found at 48 and 72 hours post-laser irradiation with 3.94 $J/cm^2$ energy fluency (P<0.05). The phosphorylated ERK level was more prominent at 3.94 $J/cm^2$ energy fluency than in the control. Conclusions: The present study demonstrated that the GaAlAs semiconductor diode laser promoted proliferation and differentiation of human PDLFs.

• Journal of Periodontal and Implant Science
• /
• 제37권1호
• /
• pp.45-51
• /
• 2007

This study evaluated the possibility of the 3-dimensional attachment of human periodontal ligament fibroblasts to a periodntally involved root surface after an EDTA treatment in vitro. The human PDL fibroblasts were isolated from the middle third of the root of periodontally healthy teeth extracted for orthodontic reasons. The cells were cultured in a medium containing Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum at $37^{\circ}C$ in humidified air containing 5% $CO_2$. Eight single-rooted teeth were obtained from patients diagnosed with periodotitis. After scaling and root planing, four teeth were etched with 24% ethylenediaminetetracetic acid (EDTA) for two minutes (Experimental group). The other four teeth were not treated with EDTA and were used as the control group. The human PDL fibroblasts were placed in the total root surface and cultured for 4 weeks. The teeth were fixed in 2.5% glutaraldehyde in PBS before preparation for the scanning electron microscopy (SEM) examination. The human PDL fibroblasts showed a healthy morphology on the root surfaces treated with EDTA (Experimental group) and a relatively unhealthy appearance on the treated root surfaces (Control group). This suggests that EDTA favorably affects the 3-dimensional attachment of human PDL fibroblasts cultured on the root surfaces. which may play an important role in periodontal healing and regeneration.