ABSTRACT
@#Periodontal ligament stem cells (PDLSCs) have the potential for multidirectional differentiation and are the preferred seed cells for periodontal tissue regeneration. In recent years, a large number of studies have confirmed that PDLSCs also possess broad immunomodulatory properties. Therefore, in-depth exploration of their specific molecular mechanisms is of great significance for the treatment of periodontitis. The aim of this paper is to summarize the research progress on the regulation of PDLSCs on various immune cells and the effect of the inflammatory environment on the immune characteristics of PDLSCs to provide an important theoretical basis for the allotransplantation of PDLSCs and improve the therapeutic effect of periodontal tissue regeneration. Studies have shown that PDLSCs possess a certain degree of immunosuppressive effect on both innate and acquired immune cells, and inflammatory stimulation may lead to the impairment of the immunoregulatory properties of PDLSCs. However, current studies are mainly limited to in vitro cell tests and lack in-depth studies on the immunomodulatory effects of PDLSCs in vivo. In vivo studies based on cell lineage tracing and conditional gene knockout technology may become the main directions for future research.
ABSTRACT
OBJECTIVES@#This study aimed to investigate how naringenin (Nar) affected the anti-inflammatory, vascula-rization, and osteogenesis differentiation of human periodontal ligament stem cells (hPDLSCs) stimulated by lipopolysaccharide (LPS) and to preliminarily explore the underlying mechanism.@*METHODS@#Cell-counting kit-8 (CCK8), cell scratch test, and Transwell assay were used to investigate the proliferation and migratory capabilities of hPDLSCs. Alkaline phosphatase (ALP) staining, alizarin red staining, lumen-formation assay, enzyme-linked immunosorbent assay, quantitative timed polymerase chain reaction, and Western blot were used to measure the expression of osteopontin (OPN), Runt-related transcription factor 2 (RUNX2), vascular endothlial growth factor (VEGF), basic fibroblast growth factor (bFGF), von Willebrand factor (vWF), tumor necrosis factor-α (TNF-α), and interleukin (IL)-6.@*RESULTS@#We observed that 10 μmol/L Nar could attenuate the inflammatory response of hPDLSCs stimulated by 10 μg/mL LPS and promoted their proliferation, migration, and vascularization differentiation. Furthermore, 0.1 μmol/L Nar could effectively restore the osteogenic differentiation of inflammatory hPDLSCs. The effects of Nar's anti-inflammatory and promotion of osteogenic differentiation significantly decreased and inflammatory vascularization differentiation increased after adding AMD3100 (a specific CXCR4 inhibitor).@*CONCLUSIONS@#Nar demonstrated the ability to promote the anti-inflammatory, vascularization, and osteogenic effects of hPDLSCs stimulated by LPS, and the ability was associated with the stromal cell-derived factor/C-X-C motif chemokine receptor 4 signaling axis.
Subject(s)
Humans , Anti-Inflammatory Agents/pharmacology , Cell Differentiation , Cell Proliferation , Cells, Cultured , Chemokine CXCL12 , Lipopolysaccharides/pharmacology , Osteogenesis , Periodontal Ligament/metabolism , Receptors, Chemokine/metabolism , Stem Cells , Interleukin-8/metabolismABSTRACT
Periodontitis is a complex chronic inflammatory disease. The invasion of pathogens induces the inflammatory microenvironment in periodontitis. Cell behavior changes in response to changes in the microenvironment, which in turn alters the local inflammatory microenvironment of the periodontium through factors secreted by cells. It has been confirmed that periodontal ligament stem cells (PDLSCs) are vital in the development of periodontal disease. Moreover, PDLSCs are the most effective cell type to be used for periodontium regeneration. This review focuses on changes in PDLSCs, their basic biological behavior, osteogenic differentiation, and drug effects caused by the inflammatory microenvironment, to provide a better understanding of the influence of these factors on periodontal tissue homeostasis. In addition, we discuss the underlying mechanism in detail behind the reciprocal responses of PDLSCs that affect the microenvironment.
Subject(s)
Humans , Periodontal Ligament , Osteogenesis , Stem Cells , Periodontitis/metabolism , Cell Differentiation/physiology , Cells, CulturedABSTRACT
Objective@# To explore the effects of red LED light mediated by the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (KEAP1-NRF2/HO-1) pathway on osteogenic differentiation and oxidative stress damage of human periodontal ligament stem cells (hPDLSCs) induced by high glucose, which provides a basis for the application of red light-emitting diode (LED) light in cell antioxidative damage.@*Methods@#hPDLSCs were identified by flow cytometric analysis, alkaline phosphatase (ALP) staining and Alizarin red-S staining; hPDLSCs were pretreated in a high glucose environment for 48 hours and irradiated with 1, 3, or 5 J/cm2 red LED light. A CCK-8 assay was performed to choose the radiant exposure that had the strongest effect on promoting the cell proliferation rate for subsequent experiments. hPDLSCs were divided into a control group, a high glucose group and a high glucose+light exposure group. ALP staining, ALP activity, Alizarin red-S staining and quantitative calcified nodules were used to detect the osteogenic differentiation of hPDLSCs; qRT-PCR and Western blot were used to detect the gene and protein expression levels of ALP, runt-related transcription factor 2 (RUNX2) and osterix (OSX); the relative mRNA expression levels of antioxidant enzyme-related genes superoxide dismutase 2 (SOD2) and catalase (CAT) in hPDLSCs were detected by qRT-PCR; reactive oxygen species (ROS) levels were detected by fluorescence microscopy and flow cytometry; the tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels in cell supernatants were detected by ELISA; the NRF2-specific inhibitor ML385 was used to inhibit the NRF2 pathway; ALP staining and ALP activity were used to detect the markers of early osteogenic differentiation; qRT-PCR was used to detect the gene expression of ALP, RUNX2 and OSX; and the protein expression levels of KEAP1, NRF2 and HO-1 were detected by Western blot.@*Results @# Identified, and irradiant exposure of 5 J/cm2 was chosen for subsequent experiments. Red LED light irradiation (5 J/cm2) improved the osteogenic differentiation of hPDLSCs induced by high glucose (P<0.05), increased the mRNA and protein levels of ALP, RUNX2 and OSX (P<0.05), upregulated the mRNA expression levels of SOD2 and CAT (P<0.05), reduced the levels of ROS (P<0.05), and reduced TNF-α and IL-1β levels in the cell supernatants (P<0.05). When ML385 was added to inhibit the NRF2 pathway, the ALP activity of cells was decreased (P<0.05); the gene expression levels of ALP, RUNX2 and OSX were downregulated (P<0.05); the protein level of KEAP1 was upregulated (P<0.05); and the protein levels of NRF2 and HO-1 were downregulated (P<0.05)@*Conclusion@#Red LED light may promote the proliferation and osteoblastic differentiation of hPDLSCs induced by high glucose through the KEAP1-NRF2/HO-1 pathway and reduce the oxidative stress damage to hPDLSCs induced by high glucose.
ABSTRACT
Context: The proliferation and differentiation of human periodontal ligament stem cells (hPDLSC) into other cell types are also mediated by mechanical stresses; they might offer therapeutic benefits in tissue regeneration and angiogenesis. Objectives: The study was planned to assess the proliferation, clonogenic potential, and osteogenic differentiation of human periodontal ligament stem cells (PDLSC) following the application of light and heavy orthodontic forces. Materials and Methods: A couple forces of 50 gm (light force) were applied on the 1st premolar on the one side and 250 gm (heavy force) on the contralateral side in the upper arch of patients requiring orthodontic treatment with extraction of all 1st premolars. After 30 days, periodontal tissues were scrapped from extracted teeth for the establishment of PDLSC in vitro. PDLC from the lower premolar teeth where no orthodontic force was applied acted as the control group. Morphology, viability, proliferating rate and population doubling time, clonogenicity, and alkaline phosphatase activity were analysed. Result: The osteogenic potential was confirmed by Alizarin red staining and the expression of the osteogenic markers by qRT?PCR. The morphology, growth kinetics, potency, and osteogenic lineage characteristics inferred the application of high force reduced the proliferative ability and osteogenesis of PDLSC, though the difference was not significant. Conclusion: The established PDLSCs demonstrated their MSC?like properties based on morphology, growth kinetics, colony forming ability, and AP activity. The culture?expanded PDLSCs showed their differentiation potential into osteocytes. The application of high force reduced the proliferative ability and osteogenesis of PDLSCs, variations were not significant.differentiation
ABSTRACT
@#Introduction: The cryopreservation of periodontal ligament stem cells (PDLSCs) required a good combination of CPA composition as a step in the preparation of PDLSCs. This study aimed to analyze the proliferative capacities and differentiation potentials of PDLSCs after slow-freezing cryopreservation with CPA in different combinations. Methods: The fourth passage of the primary PDL cells were examined their fibroblast-like morphology and colony forming unit-fibroblast (CFU-F), and characterized by surface markers for mesenchymal stem cells using flow cytometry. PDLSCs were divided into two groups of freshly-PDLSCs (fPDLSCs) and cryopreserved-PDLSCs (cPDLSCs). The PDLSCs were cryopreserved using slow freezing method with CPA in different combinations: 1) 90%FBS+10%DMEM (FD-group), 2) 90%DMEM+10%DMSO (DDs-group), 3) 90%FBS+10%DMSO (FDs-group), and 4) 100% Cell Banker (CB-group) as positive control. The proliferation of fPDLSCs and cPDLSCs were evaluated by trypan blue dye exclusion method. The multipotency of cells was assessed by Oil Red O, Alizarin Red, and Alcian Blue staining. Results: The primary PDL cells had fibroblast-like morphology and CFU-F ability. They expressed more than 95% positive MSC surface markers of CD90, CD73, CD150, and CD44, but showed less than 2% hematopoietic cell markers of CD11b/CD19/CD34/CD45 and HLA-DR. The cPDLSCs viability of FDs-group was 81.5% and 80% in -80oC and LN2, respectively. The fPDLSCs and cPDLSCs proliferation and doubling time were no statistically significant difference (p>0.05). They could differentiate into adipogenic, osteogenic, and chondrogenic differentiation. Conclusion: The cPDLSCs could maintain their proliferative capacities and differentiation potentials after slow-freezing cryopreservation with 90%FBS+10%DMSO in -80oC.
ABSTRACT
Objective @#To investigate the effect of silencing histone deacetylase 9 (HDAC9) expression on the proliferation and osteogenic differentiation of periodontal ligament stem cells (PDLSCs).@*Methods@# PDLSCs were isolated, cultured and identified in vitro. An siRNA construct specific for HDAC9 was transfected into PDLSCs (siHDAC9 group), and a nontargeting siRNA was used as a control (siNC group). The interference effect was determined by qRT-PCR. The cell cycle progression of PDLSCs was detected using flow cytometry. The proliferation activity of PDLSCs was detected via CCK-8 assay. Western blotting was used to detect the protein expression of proliferating cell nuclear antigen (PCNA). The mRNA expression of runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP) was investigated by qRT-PCR. The protein expression of RUNX2 was detected by western blotting. In addition, the formation of mineralized nodules was assessed by alizarin red staining. @*Results@#Compared with that in the siNC group, the mRNA expression of HDAC9 in the siHDAC9 group was lower (P < 0.01). Moreover, compared with those in the siNC group, the proliferation index (P<0.01), proliferation activity (P<0.05) and protein expression of PCNA (P<0.01) in the siHDAC9 group were all increased. Compared with the siNC group, the siHDAC9 group exhibited higher mRNA expression of RUNX2 and ALP (P < 0.05), and the protein expression of RUNX2 showed the same results (P < 0.01). The results of alizarin red staining showed that compared to the siNC group, the siHDAC9 group formed more mineralized nodules.@* Conclusion@#Silencing HDAC9 expression can promote the proliferation and osteogenic differentiation of PDLSCs.
ABSTRACT
BACKGROUND: The conditioned medium rich in bioactive substances can maintain the stability of proliferation and biological characteristics of stem cells. Whether the conditioned medium of human periodontal stem cells derived from healthy tissues can affect the proliferation and osteogenesis of human periodontal stem cells derived from inflammatory tissue is significant for periodontal tissue regeneration and reconstruction. OBJECTIVE: To investigate the effect of human periodontal stem cells-conditioned medium derived from healthy tissue on proliferation and osteogenic differentiation of human periodontal stem cells derived from inflammatory tissue. METHODS: HPDLSCs from normal periodontal ligaments of healthy adults were isolated, purified and cultured in vitro. Human periodontal stem cells-conditioned medium was obtained by collecting the supernatants from the serum free medium which was used for the third generation cells grown up to 80% of the bottom of the bottle after 24 hours cultivation. Human periodontal stem cells derived from inflammatory tissue were obtained from pericementum of periodontitis patients, and cultured by using limiting dilution assay. Human periodontal stem cells derived from inflammatory tissue were separately cultured under conditioned medium treatment group (conditioned medium containing 50% human periodontal ligament stem cells + 50% conventional medium) and control group (conventional medium). Protein expression levels of vimentin, Pan Cytokeratin, and stromal cell antigen STRO-1 were identified by immunofluorescence staining. The proliferative activity of cells was analyzed by MTT assay and flow cytometry. After osteogenesis in vitro, alkaline phosphatase activity and the expression levels of three osteogenesis related genes (Runx2, OPN, and OCN) were detected using alkaline phosphatase kit and RT-PCR, respectively in both groups. RESULTS AND CONCLUSION: (1) Both groups of cells were in accordance with the morphological characteristics of adult stem cells, showing long fusiform or polygonal shapes. There was no significant difference in cell morphology between the two groups under inverted phase contrast microscope. (2) The immunofluorescence staining showed that cells in both groups were positive for the specific antibodies of vimentin and STRO-1, but negative for the specific antibody of Pan Cytokeratin. (3) The results of MTT assay showed that after 3, 5 and 7 days, the proliferative activity of conditioned medium treatment group was higher than that of control group (P < 0.01). (4) Cell cycle analysis showed that compared with the control group, the number of cells in G2/M phase and S phase in conditioned medium treatment group increased significantly (P < 0.05). (5) At 5 and 7 days of osteogenic induction in vitro, alkaline phosphatase activity of conditioned medium treatment group was higher than that of control group (P < 0.05). (6) After 21 days of osteogenic induction, the expression levels of osteogenic related genes Runx2, OPN, and OCN in conditioned medium treatment group were significantly higher than those in control group (P < 0.01, P < 0.05). (7) In conclusion, human periodontal stem cells-conditioned medium derived from healthy tissues can enhance the proliferation and osteogenic differentiation of human periodontal stem cells derived from inflammatory tissue.
ABSTRACT
OBJECTIVES@#This study aims to explore the effect and molecular mechanism of long non-coding RNA (lncRNA) potassium voltage-gated channel subfamily Q member 1 overlapping transcript 1 (KCNQ1OT1) on proliferation and osteogenic differentiation in human periodontal ligament stem cells (hPDLSCs).@*METHODS@#The hPDLSCs of normal periodontal tissues were isolated and cultured. The mineralized solution induced the osteoblast differentiation of hPDLSCs. The down-regulation of lncRNA KCNQ1OT1, the overexpression of anti-miR-24-3p on the proliferation and the levels of osteocalcin (OCN), osteopontin (OPN) and alkaline phosphatase (ALP) of hPDLSCs were investigated. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the levels of lncRNA KCNQ1OT1, miR-24-3p, OCN, OPN, and ALP. Methyl thiazolyl tetrazolium (MTT) method was used to detect cell viability and activity. Cell proliferation was evaluated by MTT. Western blot was used to detect protein expression. The targeted relationship between lncRNA KCNQ1OT1 and miR-24-3p was detected by double-luciferase experiment.@*RESULTS@#The expression level of lncRNA KCNQ1OT1 increased, and that of miR-24-3p decreased during the osteogenesis of hPDLSCs (@*CONCLUSIONS@#Down-regulation of lncRNA KCNQ1OT1 inhibited the proliferation and osteogenic differentiation of hPDLSCs by targeting the up-regulated expression of miR-24-3p.
Subject(s)
Humans , Cell Differentiation , Cell Proliferation , MicroRNAs/genetics , Osteogenesis , Periodontal Ligament/cytology , Potassium , Potassium Channels, Voltage-Gated , RNA, Long Noncoding/genetics , Stem Cells/cytologyABSTRACT
@#Periodontium regeneration and repair is a controversial and difficult point in the treatment of periodontosis. The proliferation, differentiation, migration and adhesion of periodontal ligament cells and the dynamic relationship between periodontal ligament cells and their extracellular matrix proteins are the basis of periodontium morphological reconstruction, functional maintenance and tissue repair. This article reviews the mechanism of estrogen-regulated periodontal membrane fine repair and periodontal tissue reconstruction to provide the basis for follow-up research on the treatment of periodontitis and the promotion of periodontal tissue repair and reconstruction by exogenous estrogen-mediated periodontal membranes. Under the regulation of certain concentrations of estrogen, the proliferation and differentiation ability of periodontal ligament stem cells (PDLSCs) and bone mesenchymal stem cells (BMSCs) to other periodontal ligament cells were enhanced. At the same time, PDLSCs, BMSCs, human periodontal ligament fibroblasts (HPLFSs), osteoblasts and cementoblasts synthesized and secreted collagen I (COLI), osteopontin (OPN), bone sialoprotein (BSP) and osteocalcin (OCN) into the extracellular matrix. They interact with fibronectin (FN) and cementum attachment protein (CAP) in the extracellular matrix to form a variety of chain complexes and regulate each other, thus promoting the growth, migration, adhesion and fibrosis of periodontal ligament cells, repairing the collagen fiber skeleton of the periodontal ligament and adhering the two ends to the new cementum and the inherent alveolar bone.
ABSTRACT
Abstract: The abnormal increase in proliferation rate of human periodontal ligament stem cells (PDLSCs) is considered to be involved in the pathogenesis of periodontitis, a disease in which the IL-10-mediated anti-inflammatory pathway plays a critical role. This study aimed to investigate the involvement of microRNA-466l in periodontitis and to explore the possible interaction between IL-10 and microRNA-466l. PDLSCs were obtained from periodontitis-affected teeth and healthy control teeth. The expression of microRNA-466l and IL-10 mRNA was measured in PDLSCs using RT-qPCR. The proliferation ability of PDLSCs was analyzed using CCK-8 assays. Overexpression of microRNA-466l in a PDLSC cell line was established using two different types of PDLSCs, and the effect of microRNA-466l overexpression on IL-10 expression and cell proliferation were detected by western blot and CCK-8 assays, respectively. We found that expression levels of microRNA-466l and IL-10 mRNA were significantly lower (P < 0.05) in PDLSCs derived from periodontitis-affected teeth compared to those derived from healthy teeth. However, the cell proliferation ability was significantly higher in the PDLSCs derived from periodontitis-affected teeth. Meanwhile microRNA-466l overexpression decreased cell proliferation rates of both types of PDLSCs and upregulated IL-10 expression. Together, these data suggest that microRNA-466l can upregulate IL-10 and reduce the proliferation rate of PDLSCs.
Subject(s)
Humans , Adult , Periodontitis/genetics , Stem Cells/metabolism , Up-Regulation , Interleukin-10/therapeutic use , MicroRNAs/metabolism , Cell Proliferation/physiology , Periodontitis/metabolism , Periodontitis/therapy , Cell Differentiation , Blotting, Western , Interleukin-10/metabolismABSTRACT
Objective To investigate whether the low-frequency pulsed electromagnetic fields (LF-PEMFs) can enhance the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) induced by bone morphogenetic protein 9 (BMP9). Methods We isolated CD146＋/STRO-1＋ cells (namely PDLSC) from periodontal ligament cells of healthy human premolars, transfected the PDLSC with BMP9-overexpressing recombinant adenoviruses (Ad-GFP-BMP9), exposed the cells to the different intensities of PEMF stimulation (15 Hz, 0.6，1.2，1.8，2.4，3.0 mT, 1 h/12 h), and then detected the expression of runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteopontin (OPN) and osteocalcin (OCN) by qRT-PCR and Western blotting. Results Overexpression of BMP9 significantly promoted the expression of osteogenic markers (Runx2, ALP, OCN and OPN) in PDLSC (P0.05). After the intervention with 1.2, 1.8, 2.4 and 3.0 mT PEMF, the expression levels of osteogenic markers in PDLSC were significantly higher than those exposed to BMP9 alone (P0.05), and reached the peak at 2.4 mT (P0.05), indicating that LF-PEMFs enhanced BMP9-induced osteogenic differentiation of PDLSC, and there was a “window effect”. Conclusion LF-PEMFs stimulation (15 Hz, 1.8 to 3.0 mT) can enhance BMP9-induced osteogenesis of hPDLSCs in vitro.
ABSTRACT
OBJECTIVE@#To explore the mechanism of Piezo1 protein in mediating the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) via the Notch signaling pathway.@*METHODS@#In this study, young permanent teeth extracted from impacted teeth of 8-14-year- old children from January 1, 2016 to January 1, 2018 in the Department of Orthodontic, Beijing Children's Hospital were selected as cell sources. hPDLSCs were extracted by enzymatic digestion. Immunohistochemical staining was used to detect the expression of keratin and vimentin, and flow cytometry was used to identify the markers (CD146 and STRO-1) of hPDLSCs. The construction and screening of Piezo1 siRNA gene interference vector and Piezo1 gene overexpression plasmid were completed. Flexcell 4000T mechanical distraction stress instrument was used to construct hPDLSC cell model in vitro. According to the preliminary results, the experiment was divided into five groups: siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group. Real time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of Piezo1, Notch1, alkaline phosphatase (ALP), Runt-related transcription factor 2 (Runx2), osteocalcin (OCN), and bone sialoprotein (BSP). Western blot was used to detect the expression of ALP and Runx2. Fluo-3 AM probe was used to detect intracellular calcium content.@*RESULTS@#Vimentin staining of hPDLSCs was positive, and keratin staining was negative. Flow cytometry was used to detect the expression of STRO-1 and CD146, markers of hPDLSC. Empty viral vectors, siRNA-Piezo1 interference sequence, and Piezo1 overexpression vector sequence could be transfected into hPDLSC by lentivirus, and the transfection efficiency was high (approximately 90%). The reverse transcription-polymerase chain reaction (RT-PCR) results showed that there were significant differences in Piezo1 gene levels among the siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group (F=9.573, P<0.05). The level of Piezo1 in the overexpression group was significantly higher than that in the siRNA interference group (q=3.893, P<0.05). The level of Piezo1 in the stretch stress group was significantly higher than that in the blank control group (q=2.006, P<0.05). The expression of Notch1 and osteogenic genes ALP, Runx2, OCN, and BSP had the same trend. Western blot results showed that there were significant differences in the expression of ALP in the siRNA interference group, overexpression group, blank control group, stretch stress group, and negative control group (F=11.207, P<0.001). The expression level of ALP in the overexpression group was significantly higher than that in the siRNA interference group (q=2.991, P<0.05). The expression of ALP in the stretch stress group was significantly higher than that in the blank control group (q=3.007, P<0.05). The expression of Runx2 protein showed the same trend. The intracellular calcium fluorescence intensity of the overexpression group was significantly higher than that of the siRNA interference group, and the intracellular calcium fluorescence intensity of the stretch stress group was significantly higher than that of the siRNA interference group.@*CONCLUSIONS@#Mechanical stretch stress can promote the expression of Piezo1 protein. Ca2+ is the second messenger, activates the Notch1 signaling pathway and the expression of ALP, Runx2, OCN, and BSP; and promotes the osteogenic differentiation of hPDLSC. The siRNA-Piezo1 interfering plasmid can block this process. On the contrary, the overexpression plasmid of Piezo1 can promote the osteogenic differentiation of PDLSCs.
Subject(s)
Child , Humans , Alkaline Phosphatase , Cell Differentiation , Cells, Cultured , Ion Channels , Osteogenesis , Periodontal Ligament , Signal Transduction , Stem CellsABSTRACT
Objective @#To investigate the effects of casein kinase 2 interacting protein-1 (CKIP-1) on the osteogenic differentiation ability of human periodontal ligament stem cells (hPDLSCs).@*Methods @#The hPDLSCs were obtained by primary culture with periodontal ligament tissues that were collected from normal humans. Then, a lentiviral vector containing a CKIP-1-specific siRNA sequence was constructed, and the transcriptional level of CKIP-1 in hPDLSCs was downregulated after vector infection. The P4 cells were divided into four groups: the control group, negative control group (infected with a control vector), CKIP-siRNA group (infected by a CKIP-1 siRNA lentivirus) and CKIP-1 group (infected by a CKIP-1 overexpression virus). All of the cells were cultured under osteogenic induction for 21 days. Then, alizarin red staining and quantitative determination were performed to detect the osteogenic differentiation ability of the hPDLSCs. In addition, qPCR was used to detect the transcriptional level of osteogenesis-related regulatory factors, such as Runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteocalcin (OCN), and receptor activator of nuclear factor kappa-B ligand (RANKL), and the osteogenesis-related regulatory factors of the bone morphogenetic protein (BMP) signaling pathway.@*Results@#There were no differences in the indexes between the negative control group and the control group (P > 0.05). Compared with the negative control group, the CKIP-siRNA group demonstrated more mineralized nodules (P < 0.05), significantly increased calcium salt deposition (P < 0.05), and increased mRNA levels of osteogenesis-related regulatory factors, such as Runx2 , ALP, OCN, and RANKL, and the osteogenesis-related regulatory factors of BMP signaling pathway (P < 0.05). @*Conclusion@#Downregulation of CKIP-1 could promote the osteogenic differentiation of hPDLSCs, which is related to the transcription level of osteogenic-related regulatory factors.
ABSTRACT
ObjectiveNano-graphene oxide quantum dots (GOQDs) can be used to target fluorescent markers. The stem cell labeling is an important method in studying stem cell treatments. Our study aims to explore the possibility of using GOQDs as living cell fluorescent marker materials for human periodontal ligament stem cells (hPDLSCs), and to evaluate the biosecurity and effect as live cell fluorescence markers of GOQDs.Methods GOQDs were testified by TEM, DLS, UV-vis, and PL spectra. hPDLSCs were obtained by tissue cultivation and separated by single cell-derived colony selection. Then the source of the cells was carried out by immunocytochemical staining of anti-vimentin, anti-cytokeratin, and multipotent differentiation was used in the identification of stem cells. hPDLSCs were incubated with different concentrations of GOODs (0, 10, 25, and 50 μg/mL) for 24h and 72 h. Cytotoxicity and proliferation effects were determined using CCK-8, and cell cycles were detected using flow cytometry after the co-culture of GOQDs and hPDLSCs. The fluorescent labeling effect of GOQDs was tested using laser scanning confocal microscopy.ResultsThe characterization of GOQDs showed that the nanoparticles were evenly dispersed in water and showing blue light at 365 nm. TEM and DLS showed GOQDs had good dispersion, and the particle size was (6.36±1.41) nm. Immunocytochemical staining of anti-vimentin was positive while anti-cytokeratin was negative. The results of cytotoxicity showed there were no significant differences in cell activity after incubated with different concentrations of GOODs (0, 5, 10, 25, 50, 100, 200, and 400 μg/mL) (P>0.05), and there was no significant decrease in cell activity between 24h and 72h (P>0.05). There was no significant difference in the proportional distribution of G1, G2, and S phases between the two concentrations of GOQDs (0 μg/mL and 50 μg/mL) (P>0.05). Fluorescent images showed that GOQDs could enter the cell membrane and increase the fluorescence intensity at the concertation of 50 μg/mL.ConclusionGOQDs were confirmed to have good biocompatibility and could be used for live cell labeling of hPDLSCs.
ABSTRACT
ObjectiveNano-graphene oxide quantum dots (GOQDs) can be used to target fluorescent markers. The stem cell labeling is an important method in studying stem cell treatments. Our study aims to explore the possibility of using GOQDs as living cell fluorescent marker materials for human periodontal ligament stem cells (hPDLSCs), and to evaluate the biosecurity and effect as live cell fluorescence markers of GOQDs.Methods GOQDs were testified by TEM, DLS, UV-vis, and PL spectra. hPDLSCs were obtained by tissue cultivation and separated by single cell-derived colony selection. Then the source of the cells was carried out by immunocytochemical staining of anti-vimentin, anti-cytokeratin, and multipotent differentiation was used in the identification of stem cells. hPDLSCs were incubated with different concentrations of GOODs (0, 10, 25, and 50 μg/mL) for 24h and 72 h. Cytotoxicity and proliferation effects were determined using CCK-8, and cell cycles were detected using flow cytometry after the co-culture of GOQDs and hPDLSCs. The fluorescent labeling effect of GOQDs was tested using laser scanning confocal microscopy.ResultsThe characterization of GOQDs showed that the nanoparticles were evenly dispersed in water and showing blue light at 365 nm. TEM and DLS showed GOQDs had good dispersion, and the particle size was (6.36±1.41) nm. Immunocytochemical staining of anti-vimentin was positive while anti-cytokeratin was negative. The results of cytotoxicity showed there were no significant differences in cell activity after incubated with different concentrations of GOODs (0, 5, 10, 25, 50, 100, 200, and 400 μg/mL) (P>0.05), and there was no significant decrease in cell activity between 24h and 72h (P>0.05). There was no significant difference in the proportional distribution of G1, G2, and S phases between the two concentrations of GOQDs (0 μg/mL and 50 μg/mL) (P>0.05). Fluorescent images showed that GOQDs could enter the cell membrane and increase the fluorescence intensity at the concertation of 50 μg/mL.ConclusionGOQDs were confirmed to have good biocompatibility and could be used for live cell labeling of hPDLSCs.
ABSTRACT
Objective@#To investigate the effect of microRNA-26a-5p on osteogenic differentiation of human periodontal ligament stem cells (hPDLSC) and its related mechanisms.@*Methods@#hPDLSC in periodontal tissues from healthy adults and hPDLSC from periodontitis patients (PPDLSC) were isolated and cultured in vitro, respectively. The PPDLSC were divided into Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ groups. Group Ⅰ is control group, and the other four groups were transiently transfected with miR-NC, miR-26a-5p, antimiR-NC and antimiR-26a-5p lentiviral vectors, respectively. The osteogenic differentiation abilities of the cells in vitro were determined by alizarin red staining, alkaline phosphatase (ALP) activity assay and real-time quantitative PCR (qPCR). Totally 40 male mice (6-weeks) were equally divided into five groups with 8 mice in each group. The PPDLSCs cells (1×107/ml) in Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ groups, which adhered to hydroxyapatine-tricalcium phosphate (HA-TCP), were implanted into the nude mice subcutaneously and the animal models were constructed to analyze the effect of miR-26a-5p on the osteogenic differentiation of PPDLSCs in vivo. PPDLSCs were divided into A, B, C, D groups, and transfected with miR-26a-5p+Wnt5a-Wt, miR-NC+Wnt5a-Wt, miR-26a-5p+Wnt5a-Mut and miR-NC+Wnt5a-Mut in each of the above mentioned 5 groups, respectively. The luciferase activity assay was used to detect the relative luciferase in A, B, C and D groups to analyze the targeting relationship between miR-26a-5p and Wnt5a. Osteogenic differentiation related proteins expression were analyzed by western blotting.@*Results@#hPDLSC and PPDLSC were observed consistent with the characteristics of mesenchymal stem cells and had osteogenic differentiation ability in vitro. Compared with hPDLSC [(89.87±8.12)%], the osteogenic capacity of PPDLSC [(31.46±6.56)%] was significantly lower (P<0.05). The ALP activity (1.88±0.59), calcified nodules (79.88±5.92), the expression of the osteogenic differentiation markers Runt-related transcription factor 2 (Runx2) (2.40±0.70), ALP (2.10±0.60) and osteocalcin (3.00±0.90) mRNA in the PPDLSC from Group Ⅲ were significantly higher in comparison with the control group [(0.88±0.34), (29.69±2.65), (1.30±0.30), (0.09±0.25), (1.71±0.50)], while those from Group Ⅴ[(0.44±0.07), (14.83±3.05), (0.50±0.11), (0.30±0.08) and (0.80±0.17)] were significantly lower (P<0.05). In vivo studies in nude mice showed that the proportion of the osteogenic region [(34.96±5.65)%] in the miR-26a-5p group was significantly increased in comparison with the control group [(23.28±3.03)%], while in the antimiR-26a-5p group [(8.02±2.27)%] was significantly lower (P<0.05). The luciferase activity of the Group A (0.46±0.06) was significantly lower than Group B (3.46±0.45) (P<0.05). Compared with the control group, the expression levels of Wnt5a protein, calmodulin kinase Ⅱ and protein kinase C proteins in the Group Ⅲ were significantly decreased, while those in the GroupⅤ were significantly increased (P<0.05).@*Conclusions@#MicroRNA-26a-5p could promote osteogenic differentiation of PPDLSC in vivo and in vitro, and its mechanism might be inhibiting the activation of Wnt/Ca2+ signaling pathway by targeting Wnt5a.
ABSTRACT
Objective@#To investigate the effect of overexpression of Notch intracellular domain (NICD) on proliferation and osteogenic differentiation of human periodontal ligament stem cells (hPDLSC).@*Methods@#The third generation hPDLSC with stable overexpressing of NICD were assigned as experimental group, normal hPDLSC were as negative control group and hPDLSC transfected with empty vector were as blank control group. The effect of overexpressing NICD on proliferation ability of hPDLSC was detected by using cell counting kit-8 (CCK-8). Alizarin Red staining and real-time quantitative PCR (qPCR) were used to detect the effects of NICD on cementum attachment proteins (CAP), osteocalcin (OCN), Runt-related transcription factor 2 (RUNX2) and Notch signal pathway receptor Notch1. The effect of overexpressing NICD on hPDLSC osteogenic protein RUNX2 and flag marker protein (used to label NICD) were detected by using Western blotting.@*Results@#CCK-8 results showed that there were no significant differences in A values amongst the three groups for 1-2 days (P>0.05). The number of cells in the experimental group was significantly increase than that of the two control groups from the third to seventh days (A values were 0.203±0.016, 0.364±0.014, 0.449±0.020, 0.549±0.020 and 0.570±0.020, respectively) (P<0.05). Alizarin red staining showed that compared with the blank control group and negative control group, the mineralized nodules in the experimental group had smaller formation range and lighter color, and the differences were statistically significant (P<0.05). The expressions of CAP gene (0.751±0.058, 0.887±0.025), osteocalcin gene (0.592±0.051, 0.670±0.045) and RUNX2 gene (0.319±0.038, 0.684±0.055) at 14 and 21 days in the experimental group were significantly lower than those in the negative control group respectively (P<0.05). However, the expression levels of Notch1 gene at 14 and 21 days (2.507±0.047, 4.041±0.219) were significantly higher than those of negative and blank control groups (P<0.05). The results of Western blotting showed that the expressions of flag marker protein (0.167±0.007, 0.204±0.010) at 14 and 21 days in the experimental group were significantly higher than those in the negative and blank control groups (P<0.05). However, the expressions of RUNX2 protein (0.075±0.006, 0.074±0.013) at 14 and 21 days were significantly lower than that in the negative control group (0.092±0.003, 0.118±0.008) and blank control group (0.174±0.006, 0.212±0.008) (P<0.05).@*Conclusions@#Overexpression of NICD can promote the proliferation capacity of hPDLSC and inhibit its osteogenic differentiation.
ABSTRACT
Epigenetics is defined as a change in gene expression without the alteration of the genetic sequence. Such a change would be inherited by offspring. Histone acetylation is a type of epigenetics. Existing studies proposed that chronic periodontitis is related to epigenetic modification. In this review, we summarised the influence of chronic periodontitis on periodontal ligament stem cells by histone acetylation.
Subject(s)
Acetylation , Cell Differentiation , Cells, Cultured , Histones , Metabolism , Osteogenesis , Periodontal Ligament , Stem Cells , PhysiologyABSTRACT
OBJECTIVE@#This study aims to compare the osteogenic differentiation capability of stem cells derived from human inflammatory periodontal ligament tissues (iPDLSCs) with those of stem cells derived from healthy periodontal ligament tissues (hPDLSCs). Both types of tissues were induced by stromal cell derived factor (SDF-1) in vitro.@*METHODS@#iPDLSCs and hPDLSCs were primarily cultured by tissue digestion method and purified by limited dilution cloning. The cells were passaged and identified by stem cell surface marker expression through flow cytometry. Then, we used thiazolyl blue tetrazolium bromide to detect and compare the proliferation capabilities of the iPDLSCs and hPDLSCs. Express of bone volumes were detected by alizarin red staining after SDF-1 was added to the cells. Using alkaline phosphatase, we evaluated the osteogenic differentiation capability of the cells induced by SDF-1. The expression levels of the osteogenesis-related genes of the cells induced by SDF-1 were determined by reverse transcription-polymerase chain reaction.@*RESULTS@#After purification, both iPDLSCs and hPDLSCs expressed stem cell markers. hPDLCSs had a higher proliferation capability than iPDLSCs. Osteogenesis-related genes had higher expression levels in the cells induced by SDF-1 than in those without induction (P<0.05). SDF-1 at 50 and 200 ng·mL⁻¹ concentration greatly affected the differen-tiation capabilities of iPDLSCs and hPDLSCs respectively.@*CONCLUSIONS@#iPDLSCs and hPDLSCs had osteogenic differentia-tion capability. The level of osteogenic differentiation in normal and inflamed periodontal ligament stem cells increases after SDF-1 induction.