淫羊藿苷基于雌激素受体对糖皮质激素诱导的MC3T3-E1成骨抑制的影响

目的 研究淫羊藿苷(icariin,ICR)对雌性激素受体(estrogen receptor,ER)与地塞米松(dexamethasone,DEX)诱导的MC3T3-E1成骨抑制效应的影响。方法 分别以DEX 10^-5 mol·L^-1、ICR 10^-6 mol·L^-1、雌激素(E2)10^-8 mol·L^-1及ICI182780(IN)10^-5 mol·L^-1干预MC3T3-E1成熟分化过程,并通过real-time RT-PCR、Westen blot、MTT和茜素红染色法分别测定对应组各指标变化情况。结果 ICR和E2一样能够明显提高成骨细胞ALP、OPG、OC和Runx2的表达,并能够显著降低RANKL和Dickkopf的表达,对应的OPG和RANKL蛋白的表达量与mRNA的表达量相一致。ALP活性、细胞增殖能力以及Ga²⁺结节数量与对照组相比也有明显提高。同时ICR和E2都能够有效回复DEX诱导的成骨抑制效应,这种调节效应能够被IN有效的阻断。结论 ICR具有促成骨细胞增殖分化和抑制破骨细胞激活效应,并能够有效的缓解DEX诱导的成骨抑制效应;其促成骨效应具ER依赖性。     

天料木中异香豆素糖苷化合物对MC3T3-E1细胞增殖、分化及OPG/RANKL/RANK信号通路的影响

目的 探讨天料木中异香豆素糖苷化合物4-hydroxy-2-{[（benzoyl） oxy]methyl}phenyl-β-D-glucopyranoside-6-benzoate （HPGB）对小鼠胚胎成骨细胞MC3T3-E1细胞活性的影响及其作用机制。方法 体外培养MC3T3-1细胞,用不同浓度的异香豆素糖苷化合物进行干预,采用MTT法测定MC3T3-1细胞增殖情况,碱性磷酸酶（ALP）测定细胞分化情况,悬液芯片技术检测、分析糖蛋白Dickkop （DKK-1）、骨保护素（OPG）、骨桥蛋白（OPN）、骨钙素（BGP）和核因子-κB受体活化因子配体（RANKL）蛋白表达水平。Real-time PCR法检测、分析DKK-1、RANKL mRNA的表达水平。结果 异香豆素糖苷化合物在3~300 μmol/L可促进MC3T3-E1细胞增殖和分化能力,具有浓度相关性;与正常对照组相比,异香豆素糖苷化合物可提高MC3T3-E1的ALP活性。蛋白结果表明,异香豆素糖苷化合物可显著上调MC3T3-E1细胞中OPG、OPN的表达,DKK-1、RANKL蛋白表达无明显变化,但显著提高了OPG/RANKL值。同时,mRNA结果显示异香豆素糖苷化合物可显著上调MC3T3-E1细胞中OPG mRNA表达,显著提高OPG/RANKL值。结论 异香豆素糖苷化合物可通过上调OPG、OPN的表达、提高OPG/RANKL值,促进MC3T3-E1的增殖和分化。     

α-玉米赤霉醇对成骨细胞增殖、分化以及OPG和RANKL mRNA表达的影响

目的:探讨α-玉米赤霉醇(α-zearalanol,α-ZAL)对小鼠成骨样细胞MC3T3-E1增殖、分化及护骨素(osteoprotegerin,OPG)和NF-кB受体活化配体(receptor activator of nuclear factor-кB ligand,RANKL)mRNA表达的影响。方法:传代培养小鼠成骨样细胞株MC3T3-E1,采用不同浓度的α-ZAL作用于细胞72 h后,MTT法检测细胞增殖活性,PNPP法检测碱性磷酸酶(alkaline phosphatase,ALP)活性,RT-PCR法检测ALP,OPG及RANKL mRNA的表达水平。结果:10-6～10-12mol·L-1的α-ZAL可显著抑制成骨细胞的增殖(P<0.05);显著增加ALP活性(P<0.05),但不同剂量间存在作用时间差异;并且可显著上调成骨细胞内OPG/RANKL mRNA的比值(P<0.05)。结论:α-ZAL可抑制成骨细胞的增殖、促进其分化,并可通过上调OPG/RANKL mRNA表达比值抑制破骨细胞的形成,有望作为骨质疏松症的治疗药物。     

双醋瑞因对破骨细胞性骨破坏的抑制作用及机制

目的考察双醋瑞因对破骨细胞生成及骨破坏功能是否具有抑制作用，以及双醋瑞因抑制破骨细胞的作用是否与影响成骨细胞中OPG及RANKL的表达有关。方法MC3T3-E1细胞与骨髓前体细胞共培养生成破骨细胞，将TRAP染色阳性、细胞核数目≥3个的细胞作为破骨细胞，计数生成的破骨细胞。计数IL-1β作用前后典型的骨吸收陷窝以观察破骨细胞的活性。应用Western blotting法、流式细胞术及RT-PCR法在蛋白水平及基因水平观察MC3T3-E1细胞中RANKL及OPG的表达。结果双醋瑞因可显著抑制IL-1β作用下破骨细胞的生成及其骨陷窝形成功能，sRANKL的加入可逆转双醋瑞因的上述作用。双醋瑞因可在基因及蛋白水平上调MC3T3-T1细胞中OPG/RANKL的比例。结论双醋瑞因具有抑制IL-1β诱导的破骨细胞性骨破坏的作用，这一作用可能与其抑制MC3T3-E1细胞中RANKL表达同时促进OPG表达有关。     

左旋肉毒碱对MC3T3-E1成骨细胞及OPG表达的作用

目的探讨左旋肉毒碱对MC3T3-E1成骨细胞及OPG的表达作用,为临床预防骨质疏松提供参考。方法以小鼠骨细胞MC3T3-E1成骨细胞为研究对象,用左旋肉毒碱对其表达进行干预,最后,以免疫组化法检测左旋肉毒碱干预前后OPG蛋白质表达水平的改变,分析左旋肉毒碱对MC3T3-E1成骨细胞OPG的表达作用。结果 1 mmol/L左旋肉毒碱对小鼠成骨细胞无明显作用,10~100 mmol/L左旋肉毒碱能促进小鼠成骨细胞增殖,显著抑制人成骨细胞凋亡,增加小鼠骨密度。结论左旋肉毒碱可通过促进MC3T3-E1成骨细胞OPG的表达,促进成骨细胞增殖,呈剂量依赖性和时间依赖性,并且左旋肉毒碱可抑制人成骨细胞凋亡,延长其存活时间。     

帕米磷酸钠对大鼠成骨细胞RANKL/OPGmRNA表达的影响

目的观察帕米膦酸钠对新生大鼠成骨细胞核因子κβ受体活化受体配体（RANKL）／护骨素（OPG）mRNA表达的影响。方法 体外分离培养新生大鼠成骨细胞，分别观察不同浓度帕米膦酸钠或用帕米膦酸钠处理不同时间对成骨细胞RANKL／OPG mRNA表达的影响。采用半定量RT-PCR方法检测RANKL／OPG mRNA表达。结果帕米膦酸钠呈浓度依赖性降低RANKL mRNA的表达，干预24h，10^-5M抑制作用最大，约为对照组表达量的40％（P〈0．01）。同时帕米膦酸钠呈浓度依赖性增加OPG mRNA表达，10^-6M时增加最明显，约为对照组表达量的2．2倍（P〈0．01），而在10^-5M时又明显降低。10^-6M帕米膦酸钠呈时间依赖性抑制RANKL mRNA和促进OPG mRNA表达，分别于24h抑制RANKL mRNA表达、48h促进OPG mRNA表达且达最大效应（P〈0．01）。结论帕米膦酸钠可能通过调节成骨细胞RANKL／OPG的基因表达，而抑制破骨细胞介导的骨吸收。     

白藜芦醇对LPS诱导的MC3T3-E1成骨细胞的骨保护作用

目的 探讨白藜芦醇对脂多糖(LPS)诱导的MC3T3-E1成骨细胞的骨保护作用.方法 采用CCK-8法检测白藜芦醇不同浓度下MC3T3-E1成骨细胞的细胞增殖活性,对硝基苯磷酸盐法检测白藜芦醇不同浓度下MC3T3-E1成骨细胞ALP活性.将MC3T3-E1成骨细胞分为空白组(基础培养基)、对照组(LPS 2 μg/mL)和实验组(LPS 2μg/mL+白藜芦醇20 μmol/L).采用qRT-PCR检测三组成骨相关基因Runx2、ALP、骨钙素(OCN)和骨桥蛋白(OPN)mRNA表达,Western blot法检测三组细胞沉默调节蛋白1(SIRT1)蛋白表达.结果 白藜芦醇20 μmol/L是MC3T3-E1成骨细胞最适成骨浓度(P＜0.05).与空白组比较,实验组成骨相关基因Runx2、ALP、OCN和OPN mRNA表达水平和SIRT1蛋白表达水平均降低(P＜0.05);与对照组相比,实验组成骨相关基因Runx2、ALP、OCN和OPN mRNA表达水平和SIRT1蛋白表达水平升高(P＜0.05).结论 白藜芦醇能够通过提高Runx2、ALP、OCN、OPN和SIRT1相关成骨因子的表达对LPS诱导的MC3T3-E1成骨细胞发挥骨保护作用.     

克老素抑制地塞米松诱导的MC3T3-E1成骨细胞凋亡

目的探究体外转染克老素(Klotho,KL)基因对地塞米松(dexamethason,DEX)诱导的MC3T3-E1成骨细胞凋亡的影响。方法用携带KL基因的重组腺病毒(Ad-KL)及携带绿色荧光蛋白基因的重组腺病毒(Ad-GFP)感染细胞,并建立DEX诱导凋亡的细胞模型。运用荧光倒置显微镜观察重组腺病毒的转染效果,qPCR与Western blot法分析KL mRNA和蛋白表达情况;CCK-8法检测不同浓度DEX作用于MC3T3-E1细胞后的存活率及各研究组细胞的生存情况;流式细胞仪分析各研究组细胞的凋亡率;qPCR与Western blot分析凋亡标志物的mRNA、蛋白表达;免疫荧光分析caspase-9的荧光蛋白表达情况。结果重组腺病毒成功感染MC3T3-E1成骨细胞,KL组和KL+DEX组的KL mRNA与蛋白表达量较非转染组明显升高。CCK-8法检测出DEX的适宜干预浓度为2.0 mmol·L~(-1)。DEX组、GFP+DEX组较其余组细胞存活率明显降低、凋亡率明显增加,Bax、Bcl-2的mRNA与蛋白表达分别表现出增加和降低趋势;KL组细胞存活率、凋亡率,以及Bcl-2、Bax mRNA与蛋白表达较DEX组及KL+DEX组均明显改善。结论大剂量DEX的运用能够诱发MC3T3-E1成骨细胞凋亡,上调KL表达具有抵抗DEX诱导成骨细胞凋亡的作用,提示上调KL表达可改善糖皮质激素诱导性骨质疏松,为大剂量使用糖皮质激素所致医源性骨质疏松的治疗提供新的靶点。     

吴茱萸次碱抗骨质疏松作用研究

骨保护素(osteoprotegerin,OPG)是骨转换的标志物,由成骨细胞等分泌。OPG与核因子-κB受体活化因子配体(receptor activator of nuclear factor-κB ligand,RANKL)结合发挥抑制破骨细胞作用。本研究发现吴茱萸次碱(rutaecarpine,RUT)具有上调OPG表达的活性,并能显著增加小鼠胚胎成骨前体细胞MC3T3-E1及人骨肉瘤细胞U-2OS中OPG的蛋白水平。钙化结节染色实验结果表明,RUT显著促进MC3T3-E1细胞向成骨细胞分化;抗酒石酸磷酸酶(tartrate resistant acid phosphatase,TRAP)染色结果表明,RUT显著抑制RANKL诱导的小鼠巨噬细胞RAW264.7向破骨分化。体内研究发现,与卵巢去势(ovariectomized,OVX)大鼠模型组相比,RUT低剂量组(5 mg·kg^-1·day^-1)和高剂量组(45 mg·kg^-1·day^-1)灌胃给药3个月,显著增加OVX大鼠骨密度;钙黄绿素双标实验及甲苯胺蓝染色实验结果表明,RUT低剂量组在体内促进骨形成并减少骨量丢失;免疫组化结果显示RUT低剂量组能够增加大鼠股骨中OPG的表达。动物福利和实验过程均遵循中国医学科学院医药生物技术研究所动物伦理委员会的规定。综上,本研究表明RUT能上调OPG表达并在体内外促进成骨分化和抑制破骨分化。     

鹿茸胶原酶解物对地塞米松诱导成骨细胞MC3T3-E1凋亡的保护作用

目的研究鹿茸胶原酶解物(VCH)作为治疗药物对地塞米松(DEX)所致MC3T3-E1细胞损伤的影响,探究VCH对糖皮质激素性骨质疏松的保护作用。方法分别用不同浓度的VCH处理成骨细胞MC3T3-E1,MTT法测定细胞活力,通过AnnexinⅤ-FITC/PI双染流式细胞术检测细胞凋亡率,实时PCR及Western印迹检测MC3T3-E1细胞分化相关因子的m RNA及蛋白表达水平。结果 VCH 0.3 g·L~(-1)作用于MC3T3-E1细胞48 h以后能显著促进MC3T3-E1细胞的增殖;VCH可促进骨细胞的活性,可上调成骨细胞分化的标志蛋白ALP的表达和转录,可明显减少DEX所诱导的MC3T3-E1细胞凋亡(P<0.05)。结论 VCH抑制糖皮质激素引起成骨细胞凋亡,促进骨形成,为骨质疏松症的防治提供理论依据。     

Effects of Ethyl Acetate Extract of Poncirus trifoliata Fruit for Glucocorticoid-Induced Osteoporosis

Poncirus trifoliata fruit (PTF) affects the digestive and cardiovascular systems, and kidney function. The authors studied the effects of ethyl acetate (EtOAc) extract of PTF on the activities of osteoblasts and in an animal model. The main compounds of the EtOAc extract, naringin and poncirin have been confi rmed by HPLC and NMR analysis. Effects of osteoblastic differentiation were mea-sured by alkaline phosphatase (ALP) activity, osteopontin (OPN) protein expression and osteoprotegerin (OPG) mRNA expression in MC3T3-E1 cells. Also, osteoclast differentiation was measured by multinucleated cells (MNCs) formation through tartrate resistance acid phosphatase (TRAP)-positive staining. Bone mineral density (BMD) was measured before and after treatment with EtOAc extract of PTF in prednisolone-induced osteoporotic mice. Dexamethasone (DEX) decreased OPN and OPG expression level in MC3T3-E1 cells and ALP activity was decreased by DEX dose-dependently. EtOAc extract of PTF recovered the levels of ALP activity, and the expression of OPN and OPG in MC3T3-E1 cells treated with DEX. In osteoclast differentiation, multinucleated TRAP-positive cell formation was significantly suppressed by the EtOAc extract of PTF. Total body BMD was restored by EtOAc extract of PTF in prednisolone-induced osteoporotic mice. In conclusion, EtOAc extract of PTF recovered DEX-mediated deteriorations in osteoblastic and osteoclastic functions, and increased BMD in glucocorticoid-induced osteoporosis.     

Attenuation of osteoclastogenesis and osteoclast function by apigenin

The physiological effects of the flavone, apigenin on bone cells were studied. We first show that apigenin inhibits tumor necrosis factor alpha (TNFalpha)- and interferon gamma (IFNgamma)-induced secretion of several osteoclastogenic cytokines from MC3T3-E1 mouse calvarial osteoblast cell line. Ligands of the TNF receptor family constitute the most potent osteoclastic cytokines. In MC3T3-E1 cells, apigenin dose-dependently (from 5 to 20 microM) inhibits TNFalpha-induced production of the osteoclastogenic cytokines, IL-6 (interleukin-6), RANTES (regulated upon activation, normal T cell-expressed and -secreted), monocyte chemoattractant protein-1 (MCP-1) and MCP-3. In addition, apigenin inhibits IFNgamma-stimulated secretion of monokines, CXCL-9, and -10 in MC3T3-E1 cells. Next, we show that apigenin strongly inhibits differentiation of 3T3-L1 preadipocytes to adipocytes with attendant inhibition of adipocyte differentiation-induced IL-6, MCP-1, and leptin production. Inhibition of adipogenic differentiation by apigenin could be due to induction of osteogensis as it robustly upregulates mRNA levels of bone morphogenetic protein-6 (BMP-6). Finally, the presence of apigenin inhibited osteoclast differentiation from the RAW 264.7 cell line by reducing receptor activator of nuclear factor kappa ligand (RANKL)-induced expression of tartrate-resistant acid phosphatase (TRAP), RANK, and calcitonin receptor but not CCR1, resulting in the inhibition of multinucleated osteoclast formation. Similarly, apigenin inhibited expression of the osteoclast differentiation markers TRAP, RANK, and c-Fms in osteoclast precursor cells obtained from mouse bone marrow following treatment with RANKL and macrophage colony stimulating factor (MCSF). Furthermore, apigenin induced apoptosis of mature osteoclasts obtained from rabbit long bone and inhibited bone resorption. In all instances, a structurally related compound, flavone had no significant effect. These data suggest that apigenin has multiple effects on all three bone cells that could prevent bone loss in vivo.     

A comparative study of histamine activities on differentiation of osteoblasts and osteoclasts

The effects of histamine and its receptor antagonists on mouse bone marrow cells (MBMC) and MC3T3-E1 cells were studied to elucidate the precise molecular mechanisms underlying histamine activities in the respective cell types. The studied parameters were osteoclast differentiation and expressions of receptor activator of nuclear factor kappaB ligand (RANKL), histamine receptors (HR), and osteoblast differentiation markers. The osteoclastogenesis was assessed by TRAP-dye method. Expressions of RANKL, HR and the osteoblast differentiation markers were evaluated by RT-PCR analysis. In MBMC, 1 microM histamine doubled the number of osteoclast-like cells in a dose-dependent manner. Expressions of RANKL peaked at histamine concentrations of 1 microM and 0.1 microM in MBMC and MC3T3-E1, respectively. H(1)R antagonist, but not H(2)R antagonist, inhibited RANKL expressions induced by histamine in MC3T3-E1. Histamine induced expressions of cell differentiation markers in MC3T3-E1, but not in MBMC, under the conditions that RANKL expressions were induced by histamine in both types of cells. These results indicate the following: (1) Histamine induction of osteoclastogenesis is mediated by RANKL expressed via H(1)R, but not via H(2)R in mouse osteoblast-like cells; (2) and the major target of histamine action is the RANKL-RANK signaling pathway in osteocytes. This observation is consistent with the traditionally recognized histamine action of bone resorption at the osteoclast site.     

Inhibition of osteoclast formation by 3-methylcholanthrene, a ligand for arylhydrocarbon receptor: suppression of osteoclast differentiation factor in osteogenic cells

We investigated the effects of 3-methylcholanthrene (3MC), a ligand for arylhydrocarbon receptor (AhR), on osteoclastogenesis. Osteoclast-like cells, in cocultures with mouse spleen cells and clonal osteogenic stromal ST2 cells, are formed from spleen cells by a combination of the receptor activator of nuclear factor-kappaB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) produced by ST2 cells in response to 1alpha,25(OH)(2) Vitamin D(3). 3MC dose-dependently inhibited the formation of mono- and multinuclear osteoclast-like cells. However, 3MC did not inhibit the formation of osteoclast-like cells from mouse spleen cells which was supported by the exogenous soluble RANKL and M-CSF. 3MC did not affect the formation of an actin ring and pits on slices of dentine by osteoclast-like cells, both of which are typical indices of osteoclast activity. These results suggest that 3MC affects osteoclast-supporting cells such as ST2 cells but not osteoclast precursor cells and mature osteoclastic cells. When we measured the expression levels of RANKL mRNA in ST2 cells, 3MC dose-dependently decreased the level of this mRNA. However, 3MC did not affect levels of mRNAs for osteoprotegerin (OPG), M-CSF, and the receptor of 1alpha,25(OH)(2) Vitamin D(3) in ST2 cells. Furthermore, soluble RANKL was able to counteract the inhibitory effect of 3MC on the formation of osteoclast-like cells. Our findings indicate that 3MC inhibits osteoclastogenesis via the inhibition of RANKL expression in osteoblastic cells.     

xy9902对MC3T3-E1细胞的增殖和分化作用

目的研究化合物xy9902对成骨细胞MC3T3-E1的增殖和分化的影响,并初步探讨其机制。方法采用MTT比色法测定化合物对成骨细胞MC3T3-E1的增殖作用;通过硝基苯磷酸盐法测定细胞内碱性磷酸酶(A lkaline phosphatase,ALP)活性的变化,观察化合物对细胞分化的影响;用放射性配体结合法考察化合物与雌激素受体(Estrogen ic recep-tor,ER)的亲和力。结果化合物xy9902对成骨细胞有促增殖和促分化作用,这一作用可被tamoxifen阻断;xy9902与ER有亲和力,对ERα和ERβ的IC50分别为8.45×10-6mol.L-1和1.66×10-6mol.L-1。结论化合物xy9902对成骨细胞有促增殖和促分化作用,其作用机制可能与ER激动有关。     

罗格列酮对体外培养小鼠前成骨细胞系MC3T3-E1生长与分化的影响研究

目的:研究罗格列酮对体外培养小鼠前成骨细胞系MC3T3-E1生长与分化的影响。方法:以小鼠MC3T3-E1作为药物筛选的细胞模型,分别加入1、2、5、10μmo·lL-1罗格列酮干预,MTT法测定细胞活性并计算生长抑制率;流式细胞术检测细胞凋亡率;免疫组化法分析细胞中促凋亡因子Bax和抗凋亡因子Bcl-2蛋白的表达;测定细胞中分化指标碱性磷酸酶(ALP)的活性。设立只加入培养基处理的空白对照组。结果:与空白对照组比较,罗格列酮各浓度组生长抑制率、细胞凋亡率升高(P均<0.05),Bax表达增强、Bcl-2表达减弱、ALP活性下降(P均<0.05),且呈浓度依赖性。结论:罗格列酮可抑制MC3T3-E1细胞生长及分化,并诱导其凋亡;而Bax/Bcl-2可能参与凋亡的发生,并可能起关键调控作用。