• The korean journal of orthodontics
• /
• v.24 no.2
• /
• pp.295-301
• /
• 1994

The movement of teeth during orthodontic treatment requires bone remodeling process in periodontal tissue. To find out the changes occuring in the cell itself, mechanical force was applied to the cultured periodontal ligament cells. Following results were obtained from measuring the changes in cyclic AMP and $PGE_2$, $^3H$-thymidine incorporation amount in time lapse after application of mechanical force. 1. When mechanical force was applied to cultured PDL cells, the amount of cAMP in cells were increased significantly after 15 min. of force application, but were decreased gradually as time lapsed. 2. When mechanical force was applied to cultured PDL cells, the amount of PGE2 were increased at 20,40,60 min. and was significantly increased at 20 min. 3. When mechanical force was applied to cultured PDL cells, the amount of $^3H$-thymidine incorporation was some increased, but was not statistically significant.

• Biomolecules & Therapeutics
• /
• v.9 no.4
• /
• pp.244-248
• /
• 2001

This study was performed to investigate therapeutic effects of Carthami Semen, Paeoniae Raidx extracts and chitosan on the growth and differentiation of human periodontal ligament cell. We found that co-treatment of methanol extracts of Carthami Semen and chitosan significantly increased the growth of human periodontal ligament cell. However, the sigle treatment groups of the extracts showed only 20-30% of the growth increase. Alkaline phosphase activity, one of differentiation markers, was increased approximately 1.5- fold by co-treatment of methanol extract of Carthami Semen and chitosan and calcified nodule formation was also increased at the similar levels as the alkaline phosphatase. But the single treatment groups showed only 20-30% increases. These results suggest that Carthami Semen and chitosan co-treatment can be used efficiently for periodontium regeneration.

• The korean journal of orthodontics
• /
• v.36 no.6
• /
• pp.465-473
• /
• 2006

Objective: This study evaluated the effects of nitric oxide (NO) on the proliferation and differentiation of human periodontal ligament cells involved in orthodontic tooth movement. Methods: A range of concentrations of sodium nitroprusside (SNP), a NO donor, were administered to samples of human periodontal ligament cells, followed by measurement of cell viability, alkaline phosphatase (ALP) activity, and expression of osteonectin and bone sialoprotein. Results: Cell viability, ALP activity and the expression of osteonectin and bone sialoprotein were increased in human periodontal ligament cells treated with SNP concentrations of < 0.2 mM compared with controls, but were decreased with SNP concentrations of > 1.0 mM. Conclusion: NO has a biphasic effect on proliferation and differentiation in human periodontal ligament cells, with a stimulatory effect at low concentrations and an inhibitory effect at high concentrations.

• Journal of Periodontal and Implant Science
• /
• v.27 no.3
• /
• pp.459-468
• /
• 1997

Healing of periodontal tissues require the migration and proliferation of gingival fibroblasts and periodontal ligament cells. There is many evidences that the some agents like cytokines and polypeptide growth factors are mediate these cellular events in wound healing. Recently someone is interested in herbal drugs on periodontal tissue healing processes. The purpose of this study was to examine the effects of 4 herbal drugs, Carthami Flis, Moutan Redias Cortex, Scirpi Rhisoma, Seed of Carthamus tinctorius L. on human gingival fibroblasts and periodontal ligament cells. Periodontal ligament cells and gingival fibroblasts were primarily cultured from extracted premolar with non-periodontal diseases. The powder from extracted. herbal drugs were prepared with distilled water. Cells were cultured with DMEM at $37^{\circ}C$, 5% $CO_2$, 100% humidity incubator, and treated with each herbal drugs with proper concentration for 1, 2, and 3 days. The cell activity was determined by ELISA reader using MTT assay. There was the most significant elevation in $10^{-3}g/ml$ of almost herbal drugs on cellular activities. The result of this study demonstrated that Carthami Flis, Moutan Radicis Cortex, Scirpi Rhisoma, Seed of Carthamus tinctorius L. appears to have beneficial effect on healing process after periodontal treatment.

• Journal of Periodontal and Implant Science
• /
• v.23 no.1
• /
• pp.37-47
• /
• 1993

The native connective tissue attachment of the periodontium is known to be a complex consisting of gingival fibroblasts, periodontal ligament cells, gingival epithelial cells, cementum, alveolar bone and extensive extracellular matrix (collagen, glycoprotein and proteoglycans). The purpose of this study was to evaluate the effects of natural extracts on DNA, collagen and protein synthesis and inhibition of cytokine production in the gingival and periodontal ligament fibroblasts and gingival epithelial cells. Healthy gingival tissue was obtained from orthodontic treatment patients, and gingival epithelial cells, gingival fibroblasts and periodontal ligament cells were isolated and cultured from the samples. After treated with Ginseng protein, Pluronic F-68, Scutellariae Radix, centella asiatica, PDGF, IGF, DNA synthesis, total protein and collagen synthesis, and cytokine production of gingival epithelial cell, gingival fibroblast and periodontal ligamentcells were measured. MTT method for DNA synthesis, Peterkofsky and Dingerman method for total protein and collagen synthesis, and IL-1 ELISA kit for cytokine production were used. The proliferation of epithelial cells was enhanced in Centella asiatica, Ginseng protein, Pluronic F-68 and Scutellariae Radix. The activities of PDL cells were increased in PDGF, IGF, and Pluronic F-68. Higher collagen synthesis was observed in Scutellariae Radix and total protein synthesis was increased in Scutellariae Radix and PDGF. The inhibitory effects on IL-1, IL-6, $TNF-{\alpha}$ were observed in all exrracts.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.6
• /
• pp.95-103
• /
• 2019

Periodontal inflammation, a major kind of periodontal diseases, is characterized to bleed, pain, and teeth loss, and it is resulted from oxidative stress. Membrane-free stem cell extract could avoid the immunogencity rejection by removal of cell membrane. In the present study, we investigated the protective effect of membrane-free stem cell extract from oxidative stress-induced periodontal inflammation in human periodontal ligament fibroblasts (HPLF). In the cell viability measurement, membrane-free stem cell extract showed significant increase of cell viability, compared with the $H_2O_2$-treated control group. To further investigation of molecular mechanisms, we measured inflammation and apoptosis related protein expressions. Membrane-free stem cell extract attenuated inflammation-related protein expressions such as nuclear factor kappa light chain enhancer of activated B cells, inducible nitric oxide synthase, and interleukin-6. In addition, the treatment of membrane-free stem cell extract decreased apoptotic protein expressions such as cleaved caspase-9, -3, poly (ADP-ribose) polymerase, and B-cell lymphoma 2 (Bcl-2)-associated X protein/Bcl-2 ratio in the $H_2O_2$-treated HPLF cells. In conclusion, membrane-free stem cell extract exhibited anti-oxidative stress effects by regulation of inflammation and apoptosis in HPLF, suggesting that it could be used as the treatment agents for periodontal inflammatory disease.

• International Journal of Oral Biology
• /
• v.33 no.4
• /
• pp.131-135
• /
• 2008

Substance P (SP) is known to be expressed in the nerve fibers of dental pulp and periodontal tissues. It was recently reported that SP expression increased in response to orthodontic force. In the present study, we investigated the effect of SP on expression of mineralization markers and heme oxygenase-1 (HO-1) in human immortalized periodontal ligament (IPDL) cells. Cell viability was measured using a 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay. The expression of mineralization markers, including alkaline phosphatase (ALP), osteonectin (ON) and bone sialoprotein (BSP), and heme oxygenase-1 (HO-1) was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis. SP did not significantly change human IPDL cell viability, with the exception of the 24 hour treatment group. Treatment of human IPDL cells with $10^{-10}$ to $10^{-4}M$ SP upregulated mineralization marker and HO-1 expression in a time- and concentration-dependent manner. Our results suggest that SP may modulate osteoblastic cell differentiation of human IPDL cells through a mechanism involving HO-1 expression.

• International Journal of Oral Biology
• /
• v.32 no.2
• /
• pp.67-73
• /
• 2007

Periodontitis is a chronic infectious disease that leads to periodontal destruction, and is one of the major causes of tooth loss in humans. The osteoclast differentiation factor (ODF), which is also known as the receptor activator of the NF-kB ligand (RANKL), is a surface-associated ligand on bone marrow stromal cells and osteoblasts. RANKL activates its cognate receptor, RANK, on osteoclast progenitor cells, which leads to the differentiation of mononucleated precursor cells. Osteoprotegerin (OPG) is a decoy receptor that is released from stromal cells and osteoblasts to inhibit the interaction between RANKL and RANK. Although the precise mechanism of bone loss in periodontitis is unknown, the differentiation and activation of osteoclasts by OPG-ODF-RANK signaling might play the role in periodontal bone destruction. The relationship between the concentration of sex hormones and the expression of ODF and OPG was examined by treating human gingival fibroblasts and periodontal ligament cells with the normal serum concentration of estrogen or progesterone during menstruation or at menopause. The ODF/OPG relative ratio was elevated at the concentration observed during ovulation in human gingival fibroblasts and at the concentration observed between ovulation and menstruation in periodontal ligament cells treated with estrogen. However, the ratio was <1 at all concentrations in both cells treated with progesterone. In the case of menopause simulated by estrogen depletion, the ratio was <1 in human gingival fibroblasts but >1 in periodontal ligament cells.

• Journal of Periodontal and Implant Science
• /
• v.35 no.3
• /
• pp.747-760
• /
• 2005

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. Recombinant human bone morphogenetic protein-7(rhBMP-7) can differentiate the osteoprogenitor cells and induce bone formation. The purpose of this study was to evaluate the effect of BMP-7 on rat periodontal ligament cells differentiation, in vitro. In the control group, cells was cultured with DMEM media. In the experimental groups, cells were cultured with rhBMP-7 in concentration of 10, 25, 50 and 100 ng/ml. Each group was characterized by examining alkaline phosphatase activity at 3 and 5 days of culture and the ability to produce mineralized nodules of rat calvarial cells at 14 days of culture. Synthesis of type I collagen(COL-I), osteocalcin(OCN), and bone sialoprotein(BSP) was evaluated by RT-PCR at 7 days of culture. Activation of Smad proteins and p38 MAP kinase was determined by western blot analysis of the cell lysates. Alkaline phosphatase activity was significantly increased in the concentration of BMP-7 50 ng/ml and 100 ng/ml compared to the control(p<0.05). The mineralized bone nodule formation was greater with addition of 50 ng/ml and 100 ng/ml BMP-7 than the control(p<0.01). In 7 days' culture, the expressions of COL-I, BSP, and OCN was increased by BMP-7 in concentration of 10 $ng/ml{\sim}100$ ng/ml. In western blot analysis, BMP-7 treated culture cells expressed Smad 1,5,8 in dose-dependent manner, whereas BMP-7 did not activate phosphorylated form of p38 MAP kinase. These result suggested that BMP-7 stimulate rat periodontal ligament cells to differentiate toward osteoblast phenotype and increase bone matrix production by activation of BMP-Smad pathway.

• Journal of Periodontal and Implant Science
• /
• v.31 no.1
• /
• pp.179-193
• /
• 2001

previous studies have demonstrated an increase in bone mass and density with use of bisphosphonate in osteoporosis. This agent acts as an inhibitor of osteoclastic activity and results in increase of net osteoblastic activity. The purpose of the present study was to examine the effect of the bisphosphonate on osteoblastic activity of the human periodontal ligament cells in vitro. Periodontal ligament cells were primarily obtained from extracted healthy third molars. Cells of 4th to 6th passage were cultured in Dulbecco's modified Eagle's medium containing alendronate sodium or etidronate disodium at the concentration of $10^{-12}{\sim}10^{-6}mol/L$ in 5% $Co_2$ incubator at $37^{\circ}C$. Cell count and MTT assay for cellular activity were done at 2 to 7 days of culture. Alkaline phosphatase activity at 4 to 7 days of culture and formation of mineralized nodules at 28 days of culture with addition of $50{\mu}g/m{\ell}$ ascorbic acid, 10 nM${\beta}-glycerophosphate$, $10^{-7}M$ dexamethasone were evaluated. 1. Alendronate sodium Compared to the control, the proliferation of periodontal ligament cells was generally increased and the cellular activity was maintained at 2 days of culture and generally decreased at 7 days of culture. Alkaline phosphatase activity of periodontal ligament cells was inceased and the formation of mineralized nodules by periodontal ligament cells was enhanced compared to the control. 2. Etidronate disodium The proliferation of periodontal ligament cells was increased at 2 days of culture and decreased or maintained at 7 days of culture. Compared to the control, the cellular activity of periodontal ligament cells was generally decreased. Alkaline phosphatase activity of peridontal ligament cells was increased and the formation of mineralized nodules by periodontal ligament cells was enhanced compared to the control. These results suggest that alendronate sodium and etidronate disodium may have a potential effect on osteoblastic lineage of periodontal ligament cells, distinct from their inhibitory action on osteoclasts and could contribute to enhance periodontal regeneration and alveolar bone regeneration.