Characterization of the osteogenic potential of mesenchymal stem cells from human periodontal ligament based on cell surface markers

Mesenchymal stem cell （MSC）-mediated therapy has been shown to be clinically effective in regenerating tissue defects. For improved regenerative therapy, it is critical to isolate homogenous populations of MSCs with high capacity to differentiate into appropriate tissues. The utilization of stem cell surface antigens provides a means to identify MSCs from various tissues. However, few surface markers that consistently isolate highly regenerative MSCs have been validated, making it challenging for routine clinical applications and making it all the more imperative to identify reliable surface markers. In this study, we used three surface marker combinations： CD51/CD140a, CD271, and STRO-1/CD146 for the isolation of homogenous populations of dental mesenchymal stem cells （DMSCs） from heterogeneous periodontal ligament cells （PDLCs）. Fluorescence-activated cell sorting analysis revealed that 24% of PDLCs were CD51＋/CD140a＋, 0.8% were CD271＋, and 2.4% were STRO-1＋/CD146＋. Sorted cell populations were further assessed for their multipotent properties by inducing osteogenic and chondrogenic differentiation. All three subsets of isolated DMSCs exhibited differentiation capacity into osteogenic and chondrogenic lineages but with varying degrees. CD271＋ DMSCs demonstrated the greatest osteogenic potential with strong induction of osteogenic markers such as DLX5, RUNX2, and BGLAP. Our study provides evidence that surface marker combinations used in this study are sufficient markers for the isolation of DMSCs from PDLCs. These results provide important insight into using specific surface markers for identifying homogenous populations of DMSCs for their improved utilization in regenerative medicine.

Overview of noncoding RNAs involved in the osteogenic differentiation of periodontal ligament stem cells

Periodontal diseases are infectious diseases that are characterized by progressive damage to dental support tissue.The major goal of periodontal therapy is to regenerate the periodontium destroyed by periodontal diseases.Human periodontal ligament(PDL)tissue possesses periodontal regenerative properties,and periodontal ligament stem cells(PDLSCs)with the capacity for osteogenic differentiation show strong potential in clinical application for periodontium repair and regeneration.Noncoding RNAs(ncRNAs),which include a substantial portion of poly-A tail mature RNAs,are considered“transcriptional noise.”Recent studies show that ncRNAs play a major role in PDLSC differentiation;therefore,exploring how ncRNAs participate in the osteogenic differentiation of PDLSCs may help to elucidate the underlying mechanism of the osteogenic differentiation of PDLSCs and further shed light on the potential of stem cell transplantation for periodontium regeneration.In this review paper,we discuss the history of PDLSC research and highlight the regulatory mechanism of ncRNAs in the osteogenic differentiation of PDLSCs.

Low-power laser irradiation promotes the proliferation and osteogenic differentiation of human periodontal ligament cells via cyclic adenosine monophosphate

Retaining or improving periodontal ligament （PDL） function is crucial for restoring periodontal defects. The aim of this study was to evaluate the physiological effects of low-power laser irradiation （LPLI） on the proliferation and osteogenic differentiation of human PDL （hPDL） cells. Cultured hPDL cel Is were irradiated （660 nm） daily with doses of O, 1, 2 or 4 J .cm-2. Cell proliferation was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide （MTT） assay, and the effect of LPLI on osteogenic differentiation was assessed by Alizarin Red S staining and alkaline phosphatase （ALP） activity. Additionally, osteogenic marker gene expression was confirmed by real-time reverse transcription-polymerase chain reaction （RT-PCR）. Our data showed that LPLI at a dose of 2 J.cm-2 significantly promoted hPDL cell proliferation at days 3 and 5. In addition, LPLI at energy doses of 2 and 4 J.cm-2 showed potential osteogenic capacity, as it stimulated ALP activity, calcium deposition, and osteogenic gene expression. We also showed that cyclic adenosine monophosphate （cAMP） is a critical regulator of the LPLI-mediated effects on hPDL cells. This study shows that LPLI can promote the proliferation and osteogenic differentiation of hPDL cells. These results suggest the potential use of LPLI in clinical applications for periodontal tissue regeneration.

Therapeutic potential of periodontal ligament stem cells

Inflammatory periodontal disease known as periodontitis is one of the most common conditions that affect human teeth and often leads to tooth loss.Due to the complexity of the periodontium,which is composed of several tissues,its regeneration and subsequent return to a homeostatic state is challenging with the therapies currently available.Cellular therapy is increasingly becoming an alternative in regenerative medicine/dentistry,especially therapies using mesenchymal stem cells,as they can be isolated from a myriad of tissues.Periodontal ligament stem cells(PDLSCs)are probably the most adequate to be used as a cell source with the aim of regenerating the periodontium.Biological insights have also highlighted PDLSCs as promising immunomodulator agents.In this review,we explore the state of knowledge regarding the properties of PDLSCs,as well as their therapeutic potential,describing current and future clinical applications based on tissue engineering techniques.

Effects of lysophosphatidic acid on human periodontal ligament stem cells from teeth extracted from dental patients

Despite their potential applications in future regenerative medicine, periodontal ligament stem cells(PDLSCs) are difficult to obtain in large amounts from patients. Therefore, maintaining sternness while expanding the cell numbers for medical use is the key to transitioning PDLSCs from the bench to the clinic. Lysophosphatidic acid(LPA), which is present in the human body and saliva, is a signaling molecule derived from phospholipids. In this study, we examined the effects of LPA on sternness maintenance in human PDLSCs. Several spindle-shaped and fibroblast-like periodontal ligament stem-like cell lines were established from PDLSC isolation. Among these cell lines, the most morphologically appropriate cell line was characterized. The expression levels of OCT4, NANOG(a stem cell marker), and CD90(a mesenchymal stem cell marker) were high. However, CD73(a negative marker of mesenchymal stem cells) expression was not observed. Notably, immunofluorescence analysis identified the expression of STRO-1, CD146(a mesenchymal stem cell marker), and sex determining region Y-box 2 at the protein level. In addition, lipid droplets were stained by Oil red O after the induction of adipogenesis for 21 days, and mineralized nodules were stained by Alizarin Red S after the induction of osteogenesis for 14 days. Alkaline phosphate staining also demonstrated the occurrence of osteogenesis. In summary, we established a human PDLSC line, which could be applied as a cell source for tissue regeneration in dental patients. However, further studies are needed to determine the detailed effects of LPA on PDLSCs.

Human periodontal ligament stem cells repair mental nerve injury

Human periodontal ligament stem cells are easily accessible and can differentiate into Schwann cells. We hypothesized that human periodontal ligament stem cells can be used as an alternative source for the autologous Schwann cells in promoting the regeneration of injured peripheral nerve. To validate this hypothesis, human periodontal ligament stem cells （1 × 106） were injected into the crush-injured left mental nerve in rats. Simultaneously, autologous Schwann cells （1 × 106） and PBS were also injected as controls. Real-time reverse transcriptase polymerase chain reaction showed that at 5 days after injection, mRNA expression of low affinity nerve growth factor receptor was sig-nificantaly increased in the left trigeminal ganglion of rats with mental nerve injury. Sensory tests, histomorphometric evaluation and retrograde labeling demonstrated that at 2 and 4 weeks after in-jection, sensory function was significantly improved, the numbers of retrograde labeled sensory neurons and myelinated axons were significantly increased, and human periodontal ligament stem cells and autologous Schwann cells exhibited similar therapeutic effects. These findings suggest that transplantation of human periodontal ligament stem cells show a potential value in repair of mental nerve injury.

Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells Enhance the Osteoblastic Differentiation of Periodontal Ligament Stem Cells Under High Glucose Conditions Through the PI3K/AKT Signaling Pathway

Objective High glucose(HG)can influence the osteogenic differentiation ability of periodontal ligament stem cells(PDLSCs).Human umbilical cord mesenchymal stem cell-derived exosomes(hUCMSC-exo)have broad application prospects in tissue healing.The current study aimed to explore whether hUCMSC-exo could promote the osteogenic differentiation of hPDLSCs under HG conditions and the underlying mechanism.Methods We used a 30 mmol/L glucose concentration to simulate HG conditions.CCK-8 assay was performed to evaluate the effect of hUCMSC-exo on the proliferation of hPDLSCs.Alkaline phosphatase(ALP)staining,ALP activity,and qRT-PCR were performed to evaluate the pro-osteogenic effect of hUCMSC-exo on hPDLSCs.Western blot analysis was conducted to evaluate the underlying mechanism.Results The results of the CCK-8 assay,ALP staining,ALP activity,and qRT-PCR assay showed that hUCMSC-exo significantly promoted cell proliferation and osteogenic differentiation in a dosedependent manner.The Western blot results revealed that hUCMSC-exo significantly increased the levels of p-PI3K and p-AKT in cells,and the effect was inhibited by LY294002(PI3K inhibitor)or MK2206(AKT inhibitor),respectively.Moreover,the increases in osteogenic indicators induced by hUCMSC-exo were significantly suppressed by LY294002 and MK2206.Conclusion hUCMSC-exo promote the osteogenic differentiation of hPDLSCs under HG conditions through the PI3K/AKT signaling pathway.

Mass acquisition of human periodontal ligament stem cells

The periodontal ligament(PDL)is an essential fibrous tissue for tooth retention in the alveolar bone socket.PDL tissue further functions to cushion occlusal force,maintain alveolar bone height,allow orthodontic tooth movement,and connect tooth roots with bone.Severe periodontitis,deep caries,and trauma cause irreversible damage to this tissue,eventually leading to tooth loss through the destruction of tooth retention.Many patients suffer from these diseases worldwide,and its prevalence increases with age.To address this issue,regenerative medicine for damaged PDL tissue as well as the surrounding tissues has been extensively investigated regarding the potential and effectiveness of stem cells,scaffolds,and cytokines as well as their combined applications.In particular,PDL stem cells(PDLSCs)have been well studied.In this review,I discuss comprehensive studies on PDLSCs performed in vivo and contemporary reports focusing on the acquisition of large numbers of PDLSCs for therapeutic applications because of the very small number of PDLSCs available in vivo.

Effects of Aging on the Proliferation and Differentiation Capacity of Human Periodontal Ligament Stem Cells

periodontal ligament stem cells; aging; proliferation; osteogenic differentiation Objective The aim of this study is to investigate the proliferation, differentiation and apoptosis of periodontal ligament stem cells （PDLSC） derived from different aged donors, and to evaluate the effects of aging on the biological characteristics of PDLSC. Methods Periodontal ligament tissues were obtained from 24 surgically extracted human premolars during orthodontics therapy. The specimens were divided into three groups according to the donor’s age. Group A： 18-20 years, group B： 30-35 years, group C： 45-50 years. PDLSC were isolated and cultured using a tissue-block-based enzymolytic method by limiting dilution assay. The colony forming efficiency of PDLSC for three experimental groups was determined. Senescence-Associated β-Galactosidase （SA-β-G） expression in the three groups was examined using β-galactosidase staining working solution. Cell cycle and apoptosis of the PDLSC were examined by the flow cytometry. Alkaline phosphatase （ALP） activity was evaluated by ALP staining. The expression of osteoplastic differentiation related genes Runt-related transcription factor-2 （Runx-2）, Collagen Type 1 （col-1）, and ALP of PDLSC were examined by quantitative real-time RT-PCR. Results The colony forming efficiency of PDLSC in Group A, B and C was 36.67%, 22.67% and 9.33%, respectively, which decreased with donors’ age （P〈0.05）. SA-β-G expression of the senescent PDLSC in group A, B and C were 4.14%, 16.39%, 50.38%, respectively （P〈0.05）. Cells in G2/S phase was 38.73%, 29.88%, 18.25% （P〈0.05）, and the apoptosis rate was 1.57%, 4.56%, 5.84% （P〈0.05）, in group A, B and C respectively. The ALP staining in the three groups decreased with the increase of donors’ ages, and the expression of Runx-2, col-1 and ALP decreased gradually from group A to group C （all P〈0.05）, which indicated the osteogenic differentiation capacity of PDLSC decreased while donor aging. Conclusion Human PDLSC could be successfully isolated from periodontal ligament tissues of different aged donors. However, the proliferation and osteogenic differentiation capacity of PDLSC decreased while donor aging.

Effects of Apatite Nanocrystals on Proliferation, Subcellular Structure, Protein Synthesis Activity of Human Periodontal Ligament Cells

To determine the cellular events occurring in the presence of yttrtum/ hyclroxyapatite（Y / HA ） or HA nanocrystals, human periodontal ligament （HPDL） cells were isolated and maintained in culture. The specificity of the cells was evidenced by their proliferation, subcellular structure, and deposition of extracellular matrix components. The presence of nanocrystals was significantly related to an increase in the proliferation. Moreover, the presence of Y/HA nanocrystals was significantly related to an increase in the proliferation with HA nanocrystals. Transmission electron microscopy （TEM） demonstrated the phagocytotic process of HPDL cells toward Y/ HA or HA nanocrystuls . The presence of Y/ HA or HA nanocrystuls was significantly related to an increase in the protein synthesis activity of HPDL cells.

The Effects of Dense/Nanometer Hydroxyapatite on Proliferation and Osteogenetic Differentiation of Periodontal Ligament Cells

The objective of this study is to investigate possible effects of nanometer powder of hydroxyapatite on proliferation of periodontal ligament cells. With sol-gel method, the nanometer hydroxyapatite powder were fabricated. The primary periodontal ligcament cells were caltured on dense particle hydroxyapatite and nanometer particle hydroxyapatite. The effects on proliferation of periodontal ligament cell were examined in vitro with MTT （ methyl thiazolil tetracolium） test. The intercellalar effects were observed with scanning electron microscopy and energy dispersive X-ray analyzer. In addition, the influence of two materials on osteogenetic differentiation was determined with measurement of ALP （ alkaline phosphatase ） activity. It is concluded that nanometer hydroxyapatite can promote proliferation and osteogenetic differeraiation of periodontal ligament cells and it may become absorbable agent in osseous restoration.

Cell Attachment of Periodontal Ligament Cells on Commercially Pure Titanium at the Early Stage

Summary: In order to study the character of periodontal ligament cells (PDLCs) attaching on commercially pure titanium (cpTi) by morphology and metrology on the early stage (24 h), 1×105/ml PDLCs in 2 ml culture medium were seeded on cpTi discs fixed in 24-well culture plates. Morphology of cell attachment was observed by contrast phase microscope, scanning electron microscope (SEM) and fluroscence microscopy. Cell adhesion was analyzed by MTT at 0.5, 1, 2, 4 h respectively. PDLCs could attach and spread on cpTi discs. SEM showed that PDLCs had pseudopod-like protuberance. PDLCs showed different attaching phases and reached saturation in cell number at 2 h. It was concluded that PDLCs had good biocompatibility with cpTi, and showed a regular and dynamic pattern in the process of attaching to cpTi.

Influence of baicalin on the expression of receptor activator of nuclear factor-κB ligand and osteoprotegerin in human periodontal ligament cells

Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.

Effects of Tension Force on Proliferation and Differentiation of Human Periodontal Ligament Cells Induced by Lipopolysaccharides

Human periodontal ligament cells (hPDLCs), with the potential for multi-directional differentiation and reproduction, are the target cells of orthodontic tooth movement. The aim of this study was to examine the effect of mechanical tension force and lipopolysaccharides (LPS) on hPDLCs and whether they induce proliferative and differentiated characters in vitro. Tension force was applied to hPDLCs stimulated with and without LPS for 24 hrs. Real-time polymerase chain reaction (qPCR) was carried out to analyze the mRNA expression of Cyclin 2 (CCND2), WNT1 inducible signaling pathway protein 1 (WISP1), runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP). Analysis of variance (ANOVA) was used for statistical analysis. Significant differences were indicated by P < 0.05. The results showed that tension force promoted the mRNA expression of both the proliferation-related genes (CCND2 and WISP1) and differentiation-related genes (RUNX2 and ALP), and that both were enhanced by the simulation of LPS. In addition, the relative expression ratios CCND2/RUNX2 and CCND2/ALP both increased significantly after the application of tension, and this effect was further enhanced by LPS. All results indicated that with the assessed level of mechanical force loading, tension could promote both the proliferation and differentiation of hPDLCs, which could be enhanced by LPS, and that proliferation is promoted to a greater extent than differentiation. These findings may be valuable for understanding the importance of the application of suitable mechanical force in periodontal remodeling, especially in the process of orthodontic tooth movement with inflammation.

Activation of cannabinoid receptor CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in human periodontal ligament cells

Background and Objective: It has been found that human periodontal ligament (hPDL) cells express cannabinoid receptor CB2. However, the functional importance of CB2 in hPDL cells exposed to bacterial endotoxins is not known. Here we investigate if the inflammation promoter lipopolysaccharide (LPS) affects CB2 expression and if activation of CB2 regulates LPS-induced pro-inflammatory cytokine production and osteoclastogenic gene expression in hPDL cells. Methods: The hPDL cells were obtained from extracted teeth of periodontally healthy subjects. CB2 expression in hPDL cells exposed to LPS was deter- mined by quantitative real-time PCR analysis. Then, the cells were incubated with or without CB2-specific agonist HU-308 before further stimulation with LPS. In some experiments, the cells were pre-treated with CB2-specific antagonist SR144528. The production of pro-inflammatory cytokines interleukin-1 beta (IL- 1β), interleukin-6 (IL-6) and tumor necrosis factoralpha (TNF-α) was assessed by enzyme-linked immunosorbent assay (ELISA). The mRNA expression of osteoclastogenic genes osteoprotegerin (OPG) and receptor activator of NF-κB ligand (RANKL) was examined using quantitative real-time PCR analysis. Results: CB2 expression in hPDL cells was markedly enhanced by LPS. HU-308 significantly suppressed the production of IL-1β, IL-6 and TNF-α exposed to LPS, whereas SR144528 attenuated this effect. The OPG/RANKL ratio decreased when exposed to LPS, furthermore increased significantly with the addition of HU-308 and finally decreased markedly after pretreatment with SR144528. Conclusion: Our study demonstrated that activation of CB2 had anti-inflammatory and anti-resorptive effects on LPS-stimulated hPDL cells. These findings suggest that activation of CB2 might be an effective therapeutic strategy for the treatment of inflammation and alveolar bone resorption in periodontitis.

PDLSCs-Exo对炎性环境中牙周膜干细胞增殖能力及活性氧水平的影响

目的探讨牙周膜干细胞(periodontal ligament stem cells,PDLSCs)来源的外泌体(exosome,Exo)对炎性环境中牙周膜干细胞增殖及活性氧水平的影响。方法分离培养牙周膜干细胞,提取牙周膜干细胞来源的外泌体,并将其添加至正常及含有10μg/mL脂多糖(lipopolysaccharide,LPS)的牙周膜干细胞培养基中,实验对象分为PDLSCs组、PDLSCs+LPS组、PDLSCs+Exo组、PDLSCs+LPS+Exo组,检测各组牙周膜干细胞对外泌体的摄取能力、增殖能力、细胞内活性氧水平及炎性因子水平。结果在10μg/m L LPS刺激下,牙周膜干细胞增殖能力下降。组间对比,PDLSCs+LPS组较PDLSCs组、PDLSCs+Exo组、PDLSCs+LPS+Exo组增殖能力显著下降,差异有统计学意义(P<0.05);PDLSCs+LPS+Exo组增殖能力较PDLSCs+Exo组降低,差异有统计学意义(P<0.05);细胞内活性氧及炎性因子对比,PDLSCs+LPS组较其余三组细胞内活性氧水平增高,差异有统计学意义(P<0.05)。结论牙周膜干细胞来源的外泌体能够改善LPS刺激导致的牙周膜干细胞增殖活性降低,降低胞内活性氧及炎性因子水平,并提高牙周膜干细胞的抗氧化能力。

补骨脂素对人牙周膜干细胞增殖、成骨分化的促进作用及其机制

目的观察补骨脂素对人牙周膜干细胞(hPDLSCs)增殖、成骨分化的促进作用,并探讨其机制。方法将第三代hPDLSCs分为6组,5、10、25、50、100μmol/L补骨脂素组加入5、10、25、50、100μmol/L补骨脂素,对照组正常培养,采用CCK-8法检测细胞增殖能力,比色法检测碱性磷酸酶(ALP)活性,茜素红染色检测成骨诱导矿化结节。另取第三代hPDLSCs并分为两组,25μmol/L补骨脂素组加入25μmol/L补骨脂素,对照组正常培养,采用RT-PCR法检测转录因子2(Runx2)、骨桥蛋白(OPN)mRNA。结果与对照组比较,5、10、25、50、100μmol/L补骨脂素组细胞增殖能力和ALP活性增加,25μmol/L补骨脂素组细胞成骨矿化结节增加(P均<0.05);与5μmol/L补骨脂素组比较,25、50、100μmol/L补骨脂素组细胞增殖能力及10、25μmol/L补骨脂素组细胞ALP活性和25μmol/L补骨脂素组细胞成骨矿化结节增加(P均<0.05);与10μmol/L补骨脂素组比较,25、50、100μmol/L补骨脂素组细胞增殖能力增加(P均<0.05);与25μmol/L补骨脂素组比较,50、100μmol/L补骨脂素组细胞ALP活性降低(P均<0.05)。与对照组比较,25μmol/L补骨脂素组Runx2、OPN mRNA相对表达量增加(P均<0.05)。结论5~100μmol/L补骨脂素均能促进hPDLSCs的增殖和成骨分化,在5~25μmol/L呈剂量依赖性增强,在50~100μmol/L变化不明显;补骨脂素促进hPDLSCs的增殖和成骨分化的机制可能与调节Runx2信号通路有关。

miR-149-3p靶向调节Akt1介导牙周膜干细胞成骨分化的作用机制研究

目的探讨miR-149-3p靶向调节蛋白激酶B(protein kinase B,Akt1)介导牙周膜干细胞(periodontal ligament stem cells,PDLSCs)成骨分化的作用及机制。方法选取2022-01月在作者医院口腔科就诊的18~25岁患者因正畸而拔除的前磨牙或第三磨牙,分离牙周膜组织,提取人PDLSCs。免疫组织化学染色法检测角蛋白(pan-cytokeratin)和波形蛋白(vimentin)鉴定人PDLSCs。将人PDLSCs分为对照组、空载组、miR-149-3p inhibitor组和miR-149-3p mimic组。对照组人PDLSCs不进行处理,空载组、miR-149-3p inhibitor组和miR-149-3p mimic组按Lipofectamine 3000说明书方法分别将空载质粒和miR-149-3p inhibitor、miR-149-3p mimic转染到人PDLSCs。实时荧光逆转录聚合酶链反应(real-time reverse transcription polymerase chain reaction,RT-PCR)检测细胞内miR-149-3p、碱性磷酸酶(alkaline phosphatase,ALP)、Runt相关转录因子2(runt-related transcription factor 2,Runx2)、Akt1 mRNA表达;Western blot检测细胞内ALP、Runx2、Akt1蛋白表达。采用Fluo-3 AM探针检测细胞内钙离子。结果免疫组织化学结果显示,人PDLSCs二氨基联苯胺(diaminobenzidine,DAB)染色vimentin呈阳性,pan-cytokeratin呈阴性,提示PDLSCs提取成功。与对照组和空载组相比,miR-149-3p inhibitor组miR-149-3p表达显著降低,ALP、Runx2、Akt1 mRNA和蛋白表达、细胞内钙离子荧光强度均显著升高(P均<0.05);miR-149-3p mimic组miR-149-3p表达显著升高,ALP、Runx2、Akt1 mRNA和蛋白表达、细胞内钙离子荧光强度均显著降低(P均<0.05)。与miR-149-3p inhibitor组相比,miR-149-3p mimic组miR-149-3p表达显著升高,ALP、Runx2、Akt1 mRNA和蛋白表达、细胞内钙离子荧光强度均显著降低(P均<0.05)。对照组与空载组各指标比较差异均无统计学意义(P>0.05)。结论过表达miR-149-3p可靶向抑制Akt1蛋白的表达,从而抑制成骨标志物ALP和Runx2表达,降低人PDLSCs内钙离子浓度,不利于人PDLSCs成骨分化。

南蛇藤素对脂多糖诱导的人牙周膜干细胞增殖、凋亡和炎症反应的影响

目的 探讨南蛇藤素(Cel)对微小RNA(miR)-223-3p/核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)轴对脂多糖(LPS)诱导的人牙周膜干细胞(hPDLSCs)增殖、凋亡和炎症反应的影响。方法 分别给予不同浓度的Cel(1、2、4μmol/L)培养经1μg/ml LPS诱导的hPDLSCs,以未处理的hPDLSCs作为对照组。采用MTT法检测细胞存活率,选取合适的Cel浓度用于后续实验研究。将对数生长期hPDLSCs分为对照组、LPS组、Cel组(2μmol/L),采用LipofectamineTM2000转染试剂盒在Cel组的基础上转染细胞miR-223-3p inhibitor及阴性对照(inhibitor NC),并命名为Cel+inhibitor NC组、Cel+miR-223-3p inhibitor组。分别检测以上各组细胞凋亡、增殖以及炎症因水平;q RT-PCR检测各组细胞中miR-223-3p表达水平,Western blot检测细胞中NLRP3蛋白及凋亡蛋白-天冬氨酸蛋白水解酶-1(Caspase-1)表达;双荧光素酶报告基因检测实验验证miR-223-3p、NLRP3靶向关系。结果 2μmol/L Cel作用细胞后其活力最高。与对照组相比,LPS组细胞存活率、mi R-223-3p表达显著下降,肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β、IL-6含量、细胞凋亡率、NLRP3、Caspase-1表达显著升高(P<0.05);与LPS组相比,Cel组细胞存活率、miR-223-3p表达显著升高,TNF-α、IL-1β、IL-6含量、细胞凋亡率、NLRP3、Caspase-1表达显著降低(P<0.05);与Cel+inhibitor NC组相比,Cel+miR-223-3p inhibitor组LPS组细胞存活率、miR-223-3p表达显著下降,TNF-α、IL-1β、IL-6含量、细胞凋亡率、NLRP3、Caspase-1表达显著升高(P<0.05)。结论 Cel可以促进LPS诱导的hPDLSCs增殖,抑制细胞凋亡及炎症反应,可能与上调miR-223-3p、抑制NLRP3表达有关。

长链非编码RNA与牙周炎

背景:近年来,大量研究显示长链非编码RNA(long non-coding RNA,lnc RNA)在牙周炎的发病过程有重要作用,包括免疫反应过程及细胞(牙周膜干细胞、破骨细胞)的生物活性和功能,人们试图通过调控lnc RNA表达水平来实现对牙周炎症的调控及牙周组织的再生。目的:就lnc RNA在牙周炎中的研究进展进行综述,以期望更好地推进lnc RNA在牙周炎的研究。方法:第一作者检索Pub Med、中国知网等数据库建库到2023年3月发表的相关文献,以“长链非编码RNA,lnc RNA,牙周炎,牙周,免疫,炎症,牙周膜干细胞,破骨细胞,成骨分化,骨吸收,骨形成,复发,缺氧,氧化应激,静态机械应变”为中文检索词;“lnc RNA,periodontitis,periodontal,immunity,inflammation,periodontalmembranestemcells,osteoclasts,osteogenicdifferentiation,bone resorption,bone formation,recurrence,hypoxia,oxidative stress,static mechanical strain”为英文检索词,阅读每篇文献的文题、摘要进行初筛,最终筛选出87篇文献进行归纳分析。结果与结论:(1)牙周致病菌刺激机体导致免疫效应失衡引发炎症反应造成牙周组织的破坏,lnc RNA参与其调控机制。(2)lnc RNA对炎性环境的牙周膜细胞主要参与了促炎的调控,对于破骨细胞分化的影响,通过ce RNA机制进行调控,为探究牙周炎发病机制提供了新的线索。对于B细胞及巨噬细胞,lnc RNA在牙周炎中可调控其亚群的浸润、细胞活性和功能发挥。(3)lnc RNA参与牙周炎相关免疫反应主要在Toll样受体与NOD样受体两种模式识别受体与核因子κB途径这一信号通路发挥作用。(4)探究lnc RNA是否可作为牙周炎生物学标志在牙周炎的诊断及预后复发问题上有很大价值。(5)已有动物实验证实了可以通过调控lnc RNA的表达水平来逆转lnc RNA在牙周炎的作用从而起到抗炎作用,其对牙周炎的免疫治疗研究有很大价值。(6)Lnc RNA对于牙周膜干细胞的调控主要通过内源性竞争机制及各种信号通路实现,且其作用受多种因素影响,如炎性环境、机械应变及缺氧和氧化应激等,通过这些相关因素进行相关机制的研究为牙周炎的治疗提供了新的思路。