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.

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.

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.

Effects of Ginsenoside Rg-1 on the Proliferation and Osteogenic Differentiation of Human Periodontal Ligament Stem Cells

Objective： TO evaluate the effects of ginsenoside Rg-1 on the proliferation and osteogenic differentiation of human periodontal ligament stem cells （hPDLSCs） and to explore the possible application on the alveolar bone regeneration. Methods： To determine the optimum concentration, the effects of ginsenoside Rg-1 ranging from 10 to 100 μmol/L were evaluated by 3-（4,5）-dimethylthiahiazo（-z-yl）-3,5-di-phenytetrazoliumromide, alkaline phosphatase activity and calcium deposition. Expressions of runt-related transcription factor 2, collagen alpha-2（I） chain, osteopontin, osteocalcin protein were examined using real-time polymerase chain reaction. Results： Compared with the control group, a certain concentration （10 μmol/L） of the Rg-1 solution significantly enhanced the proliferation and osteogenic differentiation of hPDLSCs （P〈0.05）. However, concentrations that exceeds 100 μmol/L led to cytotoxicity whereas concentrations below 10 nmol/L showed no significant effect as compared with the control. Conclusion： Ginsenoside Rg-1 can enhance the proliferation and osteogenic differentiation of hPDLSCs at an optimal concentration of 10 μmol/L.

AMP-activated protein kinase acts as a negative regulator of high glucose-induced RANKL expression in human periodontal ligament cells

Methods We examined the expression of osteoprotegerin in hPDL cells cultured at different concentrations of glucose using real-time polymerase chain reaction （PCR）, and Western blotting analysis. AMPK phosphorylation in hPDL cells was studied using immunoprecipitate kinase assay and Western blotting. The effect of AMPK activation on RANKL expression in hPDL cells was investigated by real-time PCR and Western blotting. Results High glucose levels caused an increase in RANKL mRNA and protein expression in hPDL cells. Moreover, the amount of p-AMPK and AMPK activity was lower in hPDL cells exposed to high glucose levels than in cells exposed to normal glucose levels. Suppression of AMPK by Compound C augmented RANKL expression, and AMPK activation by metformin significantly decreased RANKL expression in hPDL cells. Additionally, metformin down-regulated RANKL expression in hPDL cells exposed to high glucose via AMPK activation. Conclusion High glucose-induced up-regulation of RANKL could be due to decreased AMPK activity, and AMPK activation may be involved in regulating of RANKL expression in hPDL cells.

Application of dental stem cells in three-dimensional tissue regeneration

Dental stem cells can differentiate into different types of cells.Dental pulp stem cells,stem cells from human exfoliated deciduous teeth,periodontal ligament stem cells,stem cells from apical papilla,and dental follicle progenitor cells are five different types of dental stem cells that have been identified during different stages of tooth development.The availability of dental stem cells from discarded or removed teeth makes them promising candidates for tissue engineering.In recent years,three-dimensional(3D)tissue scaffolds have been used to reconstruct and restore different anatomical defects.With rapid advances in 3D tissue engineering,dental stem cells have been used in the regeneration of 3D engineered tissue.This review presents an overview of different types of dental stem cells used in 3D tissue regeneration,which are currently the most common type of stem cells used to treat human tissue conditions.

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。

康复新治疗牙周炎的机制研究

目的通过研究康复新对牙周组织相关细胞增殖的影响及康复新在细胞炎症反应模型中的抗炎作用,从促进牙周组织再生和抗炎2个方面探讨康复新治疗牙周炎的相关机制。方法(1)采用淋巴细胞增殖检测法(MTS法)检测不同浓度康复新对人牙周膜成纤维细胞(hPDLFs)、人牙龈上皮细胞(hGECs)、人单核巨噬细胞(THP-1)和小鼠胚胎成骨细胞(MC3T3-E1)活性的影响;(2)通过细菌脂多糖(LPS)刺激小鼠巨噬细胞RAW264.7建立细胞炎症模型,采用实时定量聚合酶链反应(qRT-PCR)法检测康复新对细胞白细胞介素-1β(IL-1β)、IL-10、一氧化氮合酶(NOS)和基质金属蛋白酶-13(MMP-13)mRNA表达水平的影响。结果(1)与对照组比较:0.1000、0.0500、0.0250、0.0125 mg/mL的康复新组在24 h和48 h时间点均可刺激hPDLFs、THP-1和MC3T3-E1增殖(P<0.01),且促增殖作用具有浓度依赖性;(2)在炎症细胞模型中,与对照组比较,0.0500 mg/mL和0.0125 mg/mL的康复新组IL-1β和IL-10 mRNA表达水平比较,差异均无统计学意义(P>0.05),NOS和MMP-13 mRNA表达水平降低,差异有统计学意义(P<0.05)。结论康复新在一定浓度范围内能促进hPDLFs、hGECs、THP-1和MC3T3-E1增殖;康复新可抑制LPS诱导的RAW264.7细胞炎症反应,其抗炎机制可能是降低NOS和MMP-13 mRNA表达水平。康复新可能是通过促进牙周组织再生和抗感染治疗牙周炎。

成骨诱导人牙周膜干细胞来源外泌体促进炎症微环境下人牙周膜干细胞成骨分化

背景:成骨诱导间充质干细胞来源外泌体具有较强的成骨分化能力,但是在炎症微环境下对人牙周膜干细胞成骨分化的影响尚不明确。目的:探究成骨诱导人牙周膜干细胞来源外泌体在炎症微环境下对人牙周膜干细胞成骨分化的影响。方法:收集离体牙并分离培养人牙周膜干细胞,成骨诱导3 d后提取外泌体。将人牙周膜干细胞分为4组:对照组加入成骨诱导培养基,外泌体组加入含5μg/mL外泌体的成骨诱导培养基,炎症模型和炎症模型+外泌体组以1μg/mL脂多糖处理24 h构建细胞炎症微环境,炎症模型组在脂多糖处理后加入成骨诱导培养基,炎症模型+外泌体组在脂多糖处理后加入含5μg/mL外泌体的成骨诱导培养基。通过茜素红以及碱性磷酸酶染色法检测各组人牙周膜干细胞的成骨分化能力;实时荧光定量PCR与免疫印迹法检测各组人牙周膜干细胞中Runt相关转录因子2、骨桥蛋白、成骨细胞特异性转录因子Osterix(OSX)和wnt通路相关蛋白β-catenin的表达。结果与结论:(1)与对照组相比,炎症模型组碱性磷酸酶染色相对面积、矿化结节染色相对面积以及Runt相关转录因子2、骨桥蛋白、OSX的表达量显著降低(P <0.05);(2)与炎症模型组相比,炎症模型+外泌体组碱性磷酸酶染色相对面积、矿化结节染色相对面积以及Runt相关转录因子2、骨桥蛋白、OSX的表达显著升高(P <0.05);(3)与对照组相比,炎症模型组wnt通路相关蛋白β-catenin表达量显著增加(P <0.05);与炎症模型组相比,炎症模型+外泌体组β-catenin表达量显著降低(P <0.05)。结果表明,成骨诱导人牙周膜干细胞来源外泌体可促进炎症微环境下人牙周膜干细胞的成骨分化,其作用机制可能与wnt/β-catenin信号通路有关。

高糖炎性环境下KLF4调控人牙周膜干细胞能量代谢的机制初探

目的:探究高糖炎性环境下Krüppel样因子4(KLF4)对人牙周膜干细胞(hPDLSCs)线粒体能量代谢和成骨分化的影响。方法:利用免疫荧光和Western blot实验研究高糖炎性环境下KLF4在hPDLSCs的定位和表达情况。通过碱性磷酸酶(ALP)和茜素红染色等检测高糖炎性环境下hPDLSCs成骨能力。通过慢病毒敲低和过表达技术,结合实时荧光定量PCR与Western blot实验检测病毒感染后KLF4的表达,检测KLF4对hPDLSCs成骨分化的影响。采用核酸酶靶向切割和释放(CUT&RUN)技术,分析高糖炎性环境下hPDLSCs中KLF4结合的DNA及相关信号通路变化。使用Seahorse能量代谢仪探索KLF4对hPDLSCs氧化呼吸能力的影响。结果:高糖炎性环境下,hPDLSCs中KLF4表达下调、ALP活性降低、钙结节形成减少(均P<0.001),Runt相关转录因子2(RUNX2)、骨钙素(OCN)表达降低(均P<0.001)。敲低KLF4,导致hPDLSCs的ALP活性降低(P<0.001),钙结节形成减少(P<0.001);过表达KLF4促进hPDLSCs的成骨分化。高糖炎性环境下,KLF4下游调控基因富集于能量代谢、成骨等相关通路。敲低KLF4导致hPDLSCs线粒体耗氧率(OCR)水平下调,而细胞外酸化率(ECAR)水平上调;过表达KLF4使OCR水平上调,而ECAR水平下调。结论:在高糖炎性环境下,hPDLSCs的成骨分化能力受损,KLF4可能通过上调线粒体氧化磷酸化能力来恢复hPDLSCs的成骨分化能力。

西格列汀激活基质细胞衍生因子-1/CXC趋化因子受体4信号通路对脂多糖诱导的人牙周膜干细胞增殖、凋亡、炎症和成骨分化的影响

目的 探讨西格列汀对脂多糖(LPS)诱导的炎症微环境下人牙周膜干细胞(hPDLSCs)增殖、凋亡、炎症和成骨分化的影响及分子机制。方法 体外培养hPDLSCs,用不同浓度的西格列汀处理后检测细胞活力,以确定后续西格列汀实验浓度。采用1μg/mL LPS刺激诱导24 h建立hPDLSCs炎症模型并分为空白组、对照组、西格列汀低浓度组(0.5μmol/L)、西格列汀中浓度组(1μmol/L)、西格列汀高浓度组(2μmol/L)、西格列汀高浓度+基质细胞衍生因子-1 (SDF-1)/CXC趋化因子受体4 (CXCR4)通路抑制剂(AMD3100)组(2μmol/L+10μg/mL)。细胞计数试剂盒-8检测培养24、48、72 h后的hPDLSCs增殖活性;流式细胞术检测培养72 h后hPDLSCs凋亡情况;诱导成骨分化21 d后茜素红染色检测hPDLSCs成骨分化能力,试剂盒测定hPDLSCs中碱性磷酸酶(ALP)活性;酶联免疫吸附检测hPDLSCs培养上清液中炎症因子肿瘤坏死因子(TNF)-α、白细胞介素(IL)-1β、IL-6水平;实时荧光定量聚合酶链反应(RT-qPCR)检测hPDLSCs中成骨分化相关基因Runt相关转录因子2 (RUNX2)、骨钙素(OCN)、骨桥蛋白(OPN)及SDF-1和CXCR4 mRNA表达;Western blot检测hPDLSCs中SDF-1、CXCR4蛋白表达。结果 与空白组比较,对照组hPDLSCs增殖活性、矿化结节数量、染色强度、ALP活性和RUNX2、OCN、OPN mRNA及SDF-1、CXCR4 mRNA和蛋白表达水平显著降低,凋亡率、TNF-α、IL-1β、IL-6水平显著升高(P<0.05);与对照组比较,西格列汀低、中、高浓度组hPDLSCs增殖活性、矿化结节数量、染色强度、ALP活性和RUNX2、OCN、OPN mRNA及SDF-1、CXCR4 mRNA和蛋白表达水平依次升高,凋亡率、TNF-α、IL-1β、IL-6水平依次降低(P<0.05);AMD3100可部分逆转高浓度西格列汀对LPS诱导的hPDLSCs的作用效果(P<0.05)。结论 西格列汀可能通过激活SDF-1/CXCR4信号通路促进LPS诱导的炎症微环境下hPDLSCs的增殖和成骨分化,抑制hPDLSCs凋亡和炎症反应。

熊果酸干预人牙周膜干细胞成骨分化的效应

背景:熊果酸可促进骨髓间充质干细胞向成骨细胞定向分化,但其对人牙周膜干细胞是否具有促成骨作用目前相关报道少见。目的:探讨熊果酸对人牙周膜干细胞增殖和成骨分化能力的影响。方法:分离、培养人牙周膜干细胞,取第3代细胞,分别采用含不同浓度(0,1,2,4,6,8μmol/L)熊果酸的普通培养基干预,干预1,3,5,7 d后,采用CCK-8法检测细胞增殖,筛选适宜干预浓度。取第3代人牙周膜干细胞,分别用含0,1,2,4μmol/L熊果酸的成骨诱导液干预,干预7 d后,采用qRT-PCR法检测碱性磷酸酶、Runx2、骨钙素m RNA的表达,干预14 d后,茜素红染色观察矿化结节形成。取第3代人牙周膜干细胞,对照组加入成骨诱导液,熊果酸组、拮抗剂组分别加入含熊果酸(2μmol/L)、骨形态发生蛋白信号通路拮抗剂Noggin的成骨诱导液,熊果酸+拮抗剂组加入含熊果酸(2μmol/L)、骨形态发生蛋白信号通路抑制剂Noggin的成骨诱导液,培养7 d后,采用qRT-PCR和Western blot检测骨形态发生蛋白2、Smad1、骨桥蛋白、Runx2的m RNA及蛋白表达。结果与结论:(1)1,2,4μmol/L熊果酸可促进人牙周膜干细胞的增殖,6,8μmol/L熊果酸可抑制人牙周膜干细胞的增殖,后续实验选择1,2,4μmol/L熊果酸进行干预;(2)与0μmol/L相比,1,2,4μmol/L熊果酸可促进碱性磷酸酶、Runx2、骨钙素m RNA的表达以及矿化结节的形成(P<0.05),其中以2μmol/L熊果酸效果最显著;(3)与对照组比较,熊果酸组骨形态发生蛋白2、Smad1、骨桥蛋白、Runx2的mRNA及蛋白表达均升高(P<0.05),拮抗剂组上述指标的mRNA及蛋白表达均降低(P<0.05);与熊果酸组比较,熊果酸+拮抗剂组上述指标的mRNA及蛋白表达均降低(P<0.05);(4)结果表明,熊果酸可通过激活骨形态发生蛋白信号通路促进人牙周膜干细胞的成骨分化。

淫羊藿苷预处理增强人牙周膜干细胞对M1型巨噬细胞的影响

背景:人牙周膜干细胞对M1型巨噬细胞促炎功能有一定抑制作用,具有抗炎等药理活性的淫羊藿苷是否能增强人牙周膜干细胞对M1型巨噬细胞的抑制作用尚不明确。目的:探究淫羊藿苷预处理人牙周膜干细胞后对M1型巨噬细胞的影响。方法:分离培养原代人牙周膜干细胞,并进行鉴定。对THP-1细胞进行诱导,采用免疫荧光染色及PCR进行M1型巨噬细胞鉴定。用含浓度10^(-7),10^(-6),10^(-5),10^(-4)mol/L淫羊藿苷的α-MEM完全培养基培养人牙周膜干细胞1,3,5,7 d,采用CCK-8法筛选合适的淫羊藿苷浓度进行实验。将α-MEM完全培养基、未处理的人牙周膜干细胞α-MEM条件培养基及淫羊藿苷预处理24 h的人牙周膜干细胞α-MEM条件培养基与RPMI-1640完全培养基以1∶1的比例对M1型巨噬细胞进行条件培养,分别为对照组、未处理组及预处理组,24 h后RT-PCR法检测M1型巨噬细胞炎症因子的mRNA表达情况;ELISA法检测M1型巨噬细胞炎症因子的蛋白表达情况;Western blot检测M1/M2型巨噬细胞表面标记物及核转录因子κB通路相关蛋白的表达。结果与结论:(1)CCK-8检测结果显示,10^(-7),10^(-6),10^(-5),10^(-4)mol/L淫羊藿苷对人牙周膜干细胞均无细胞毒性,且从第5天起,各浓度都提高了细胞活力,促进细胞增殖,选择10^(-4)mol/L淫羊藿苷进行后续实验。(2)RT-PCR法及ELISA检测结果显示,与对照组相比,未处理组及预处理组均降低了M1型巨噬细胞白细胞介素1β、白细胞介素6及肿瘤坏死因子α的表达与分泌(P<0.05),且预处理组低于未处理组(P<0.05)。(3)Western blot检测结果显示,与未处理组相比,预处理组CD86的表达明显降低(P<0.05);与对照组相比,未处理组和预处理组M2型巨噬细胞表面标志物CD206的表达均升高(P<0.01),且预处理组明显高于未处理组(P<0.01);M1型巨噬细胞经24 h条件培养后,与对照组相比,核转录因子κB/P65的表达在未处理组和预处理组均有降低(P<0.01),p-IκBα的表达仅在预处理组降低(P<0.01);与未处理组相比,预处理组核转录因子κB/P65和p-IκBα的表达均显著降低(P<0.05),而IκBα在3组中的表达差异无显著性意义。(4)上述结果证实,淫羊藿苷增强了人牙周膜干细胞对M1型巨噬细胞的抑制作用,此作用可能与抑制了巨噬细胞的核转录因子κB信号通路相关。

缓释地塞米松改性丝胶蛋白水凝胶支架促进大鼠下颌骨缺损修复:基于调节巨噬细胞M2极化

目的 探究改性丝胶蛋白水凝胶(SMH-CD/DEX)调节巨噬细胞极化促进骨缺损修复的能力。方法 将地塞米松搭载于丝胶蛋白水凝胶构建SMH-CD/DEX水凝胶。通过扫描电镜、傅里叶红外光谱、细胞活性实验和释放曲线测定,对SMH-CD/DEX水凝胶的形貌、化学性质及生物活性进行表征分析。通过Western blot、RT-qPCR、流式细胞术检测THP-1巨噬细胞中iNOS和Arg-1蛋白表达量,IL-6、IL-10、Arg-1、iNOS基因表达水平及CD86、CD206的表达比例。在共培养条件下通过Western blot,RT-qPCR检测h PDLSCs人牙周膜干细胞COL1A1和Runx2蛋白的表达量,ALP、Runx2、OCN、BMP2基因表达量,并进行碱性磷酸酶染色和茜素红染色。在大鼠下颌骨骨缺损模型植入水凝胶,通过Micro-CT扫描和组织病理染色分析新骨形成情况。结果 通过主客体相互作用与化学偶联改性丝胶蛋白水凝胶,成功构建SMH-CD/DEX水凝胶。SMH-CD/DEX水凝胶能够有效提高巨噬细胞M2极化相关标志物的IL-10及Arg-1的表达量(P<0.001);并降低M1极化相关标志物IL-6及iNOS表达(P<0.001)。在共培养体系中,SMH-CD/DEX水凝胶可提高人牙周膜干细胞的成骨分化相关标志物ALP、BMP2(P<0.05)及COL1A1(P<0.001)、Runx2表达量(P<0.01)。碱性磷酸酶染色和茜素红染色结果显示,SMH-CD/DEX水凝胶能够有效促进人牙周膜干细胞成骨分化。Micro-CT及HE、Masson染色结果显示,SMH-CD/DEX水凝胶有效促进骨缺损再生修复(P<0.05)。结论 SMH-CD/DEX水凝胶能够调节巨噬细胞M2极化促进干细胞成骨分化并促进骨缺损愈合。

基于转录组测序探讨柚皮素对脂多糖作用下人牙周膜干细胞的抗炎作用及相关机制

目的联合使用转录组测序(RNA-seq)和生信分析,探究柚皮素(Nar)对脂多糖(LPS)刺激下的人牙周膜干细胞(hPDLSCs)的抗炎作用及机制。方法采用细胞计数试剂盒(CCK-8)、实时荧光定量逆转录聚合酶链反应(qRT-PCR)、酶联免疫吸附试验(ELISA)检测Nar对LPS刺激下hPDLSCs增殖及炎性因子表达情况,筛选出Nar的最佳抗炎浓度。采用RNA-seq,以|log2FC|≥1且P≤0.05为标准筛选出显著差异基因(DEGs)。采用火山图分析、京都基因与基因组百科全书(KEGG)通路富集分析、String数据库及Cytoscape的MCODE模块筛选核心基因。ELISA、qRT-PCR和蛋白印迹实验(Western blot)检测对核因子κB(NF-κB)信号通路的影响。结果适宜浓度的Nar可减轻LPS刺激下hPDLSCs的炎症因子表达,促进其增殖,20μmol/LNar抗炎效果最佳。RNA-seq提示炎症相关信号通路显著富集。Nar通过抑制NF-κB信号通路产生抗炎作用,Nar与NF-κB抑制剂BAY11-7802效果相似。结论Nar可以通过抑制NF-κB信号通路发挥抗炎作用。Nar可能是辅助治疗牙周炎的一种潜在的药效成分。

老鹳草素对炎性微环境中人牙周膜干细胞成骨分化的影响

目的探究老鹳草素(geraniin,GER)对炎性微环境中人牙周膜干细胞(hPDLSCs)成骨分化及核因子-κB(NF-κB)的影响。方法将从人牙周膜组织中分离鉴定的hPDLSCs分为对照组、肿瘤坏死因子-α(TNF-α)组、0.1μmol/L老鹳草素组(0.1GER组)、1μmol/L老鹳草素组(1GER组)、10μmol/L老鹳草素组(10GER组)和100μmol/L老鹳草素组(100GER组)。对照组hPDLSCs用成骨诱导培养液培养,TNF-α组hPDLSCs用含有10 ng/mL TNF-α的成骨诱导培养液培养,0.1GER组、1GER组、10GER组和100GER组hPDLSCs分别用含有10 ng/mL TNF-α以及0.1,1,10,100μmol/L的老鹳草素的成骨诱导培养液培养。培养21 d,采用可见光比色法检测各组细胞中碱性磷酸酶(ALP)活性。采用茜素红染色观察钙化结节形成。通过qRT-PCR检测Runt相关转录因子2(RUNX2)、骨桥蛋白(OPN)、骨钙素(OCN)、osterix(OSX)、牙本质涎磷蛋白(DSPP)mRNA相对表达量。通过Western blot检测NF-κB p65磷酸化水平。结果与对照组比较,TNF-α组细胞的相对ALP活性和钙化结节程度均降低(P<0.05),RUNX2、OPN、OCN、OSX和DSPP的mRNA相对表达量均降低(P<0.05),NF-κB p65相对磷酸化水平升高(P<0.05)。与TNF-α组比较,1GER组、10GER组、100GER组细胞的相对ALP活性和钙化结节程度均升高(P<0.05),RUNX2、OPN、OCN、OSX和DSPP对的mRNA相对表达量均升高(P<0.05),NF-κB p65相对磷酸化水平降低(P<0.05)。结论老鹳草素可提高炎性微环境中hPDLSCs的成骨分化能力,其机制可能与抑制NF-κB的激活有关。

不同浓度钙离子干预人牙周膜干细胞的增殖和成骨分化

背景:钙离子作为第二信使,调控着众多的生理过程,但在牙周膜干细胞成骨分化方面的生物学效应尚不明确。目的:探讨钙离子在人牙周膜干细胞增殖和成骨分化过程中的作用。方法:使用含钙离子浓度为0(对照组),1,2,5,10,15 mmol/L的完全培养基及成骨诱导液对第3代人牙周膜干细胞进行增殖能力检测及成骨诱导。培养1,3,5,7 d使用CCK-8检测细胞增殖能力;在成骨诱导第3,7天采用Real-Time PCR和Western blot检测RUNX2、OPN、OCN的基因及蛋白表达;成骨诱导第14天时进行茜素红染色分析人牙周膜干细胞的成骨矿化情况。结果与结论:①CCK-8检测结果显示,2,5 mmol/L钙离子组人牙周膜干细胞在第5,7天的增殖能力优于对照组(P<0.05);②体外成骨诱导7 d后,5,10 mmol/L钙离子组人牙周膜干细胞中RUNX2、OPN、OCN的表达高于对照组(P<0.05);③体外成骨诱导14 d后,含钙离子组人牙周膜干细胞的矿化结节数量均高于对照组(P<0.05);④以上结果表明,在一定浓度范围内,钙离子可促进人牙周膜干细胞的增殖与成骨分化。

miR-150靶向β-catenin调控人牙周膜干细胞成骨分化能力的机制研究

目的 体外研究miR-150对人牙周膜干细胞(human periodontal ligament stem cells,hPDLSCs成骨分化能力的调控作用及其分子机制。方法 分离培养hPDLSCs并进行成骨向分化诱导,q-PCR检测miR-150及成骨相关基因(RUNX2、OCN、OPN、ALP)的表达;hPDLSCs中转染miR-150沉默(inhibitor)及过表达模拟物(mimics),q-PCR检测miR-150和β-catenin的表达,茜素红染色实验检测hPDLSCs成骨分化能力的变化;qPCR及Western blot检测沉默及过表达miR-150后β-catenin表达水平的变化;双荧光素酶报告基因实验验证miR-150的潜在靶基因;在hPDLSCs中过表达miR-150并加入SKL2001(Wnt/β-catenin通路激动剂),检测β-catenin表达及hPDLSCs成骨分化能力的变化。结果 RUNX2、OCN、OPN、ALP基因在hPDLSCs成骨向分化诱导后表达明显上调,而miR-150的表达则显著下调;q-PCR及茜素红染色结果显示抑制miR-150可明显上调成骨相关基因的表达并促进hPDLSCs成骨向分化,而过表达miR-150则结果相反;生物信息学分析显示β-catenin为miR-150的潜在靶基因,双荧光素酶报告进一步验证β-catenin为miR-150的靶基因;而SKL2001激活β-catenin后可逆转miR-150 mimics对hPDLSCs成骨分化的抑制作用。结论 miR-150可靶向β-catenin调控hPDLSCs的成骨向分化能力,提示miR-150在牙周组织工程损伤修复中发挥重要作用。