护骨素及配体在卵巢切除大鼠骨组织的蛋白表达和细胞定位

目的对卵巢切除和假切大鼠骨组织中护骨素（OPG）和配体（RANKL）的表达进行比较，观察不同分化阶段成骨细胞的OPG和RANKL表达变化，深入地探讨成骨细胞对破骨细胞发生的调控作用。方法9月龄雌性大鼠分为卵巢切除组和假切组，相同条件喂养3月后处死，取材制作骨病理切片，用免疫组织化学方法测定大鼠股骨OPG和RANKL的蛋白表达，用图像分析软件对蛋白表达情况半定量分析，对各组数据和组织形态进行分析比较。结果OPG和RANKL蛋白在骨组织表达相对稳定。RANKL主要表达在增殖活跃的成骨细胞和幼稚的骨细胞，OPG主要表达在成熟骨细胞和静息骨衬里细胞。与假切组相比，卵巢切除组骨组织内RANKL表达升高（P〈0．01），OPG表达降低（P〈0．05）。结论卵巢切除后骨组织中RANKL/OPG升高，破骨细胞活性增强，骨转换加快。不同发育阶段的成骨细胞对破骨细胞有不同的调节作用，幼稚阶段表现出对破骨细胞的诱导作用，而成熟阶段则表现为抑制作用。     

RANK/RANKL/OPG系统在骨髓瘤骨病中的作用

多发性骨髓瘤骨病以进行性骨质破坏为主要特征,主要原因是破骨细胞大量生成和激活.核因子κB受体活化因子(RANK)及其配体(RANKL)、骨保护蛋白(OPG)是调节破骨细胞功能和活性的关键性调节因子,在骨髓瘤引起的骨质破坏中发挥重要作用.研究表明骨髓瘤患者局部RANKL/OPG比例增高可能是引起骨吸收的关键因素.临床前研究表明使用重组OPG或RANK可以抑制破骨形成,减少骨吸收,改变骨髓微环境,预防骨髓瘤骨病的形成,间接抑制骨髓瘤的发展.     

共培养体系中重组结核杆菌热休克蛋白10对破骨细胞相关基因表达的影响（R68)

目的观察重组结核杆菌热休克蛋白10(CPN10)对成骨细胞(OB)-外周血单个核细胞(PBMs)共培养体系中破骨细胞生成及相关基因表达的影响。方法建立培养上清相通但二者互相不接触的成骨细胞一单个核细胞共育模型。实验分对照组和CPN10(10μg/ml)处理组。主要观察指标:①采用TRAP染色及扫描电镜检测破骨细胞生成及小牛骨磨片吸收陷窝,②应用Realtime PCR检测与破骨细胞生成相关基因NFATc1、c-Fos、RANKL、OPG的基因表达。结果两组细胞均有TRAP阳性多核破骨细胞生成,并在小牛骨磨片上形成吸收陷窝;但对照组所获TRAP阳性多核细胞数目、吸收陷窝数目及面积均显著小于CPN10组。Realtime PCR检测结果显示CPN10组与对照组相比NFATc1、c-Fos、RANKL、OPG相对浓度分别为7.410±1.738、8.844±1.981、22.4272±2.058、2.445±0.2517(P0.05),对照组各基因表达均显著低于CPN10组。结论 CPN10在成骨细胞-单个核细胞(OB-PBMs)共培养体系中可促进OC的生成及骨吸收,CPN10通过对成骨细胞的作用,致其分泌的OPG/RANKL比例失调,并上调破骨细胞相关基因NFATc1、c-Fos、RANKL、OPG的基因表达。     

BMP-2对体外培养人牙囊细胞表达OPG和RANKL的影响

目的：研究BMP-2对体外培养人牙囊细胞表达OPG和RANKL的影响。方法：第5代人牙囊细胞免疫组化染色,检测人牙囊细胞中OPG和RANKL蛋白的表达;第5代人牙囊细胞与浓度为100ng/ml的BMP-2共同孵育0h、1h、3h、6h、12h、18h,RT-PCR法检测OPG和RANKL基因表达的变化。结果：人牙囊细胞OPG、RANKL免疫组化染色阳性;100ng/ml的BMP-2上调OPG蛋白的分泌,最佳效应时间为12～18h,下调RANKL基因的表达,最佳效应时间为6～12h。结论：人牙囊细胞存在OPG、RANKL蛋白的表达;100ng/ml的BMP-2可增强人牙囊细胞OPG蛋白分泌和基因表达,减弱RANKL基因的表达,降低RANKL/OPG的比值,抑制破骨细胞的形成。     

NF-κB受体活化因子配基和骨保护素的表达与脊柱浆细胞骨髓瘤的关系

目的探讨脊柱浆细胞骨髓瘤（plasma cell myeloma,PCM）中NF-κB受体活化因子配基（receptor activator of nuclear factorκB ligand,RANKL）和骨保护素（osteoprotegerin,OPG）的表达与脊柱PCM相关骨病的关系。方法应用免疫组织化学链霉菌抗生物素蛋白-过氧化物酶连结（SP）法检测63例脊柱PCM及10例正常骨髓中RANKL和OPG的表达,并结合骨髓瘤患者临床影像学资料对骨髓瘤骨病（myeloma bone disease,MBD）进行分级。行χ2检验、Kruskal-Wallis秩和检验或log-rank检验分析相关数据。结果脊柱PCM中RANKL表达明显高于正常骨髓,差异有统计学意义（P〈0.01）;OPG表达明显低于正常骨髓,差异有统计学意义（P〈0.01）。RANKL的表达与MBD分级相关（P〈0.05）,骨病分级越高,RANKL的表达越高。骨病分级与脊柱PCM预后有相关性,其平均生存期为Ⅲ级少于Ⅱ级少于Ⅰ级。结论脊柱PCM中存在RANKL/OPG系统的平衡失调。RANKL作为破骨细胞刺激因子可能在PCM的溶骨性病变和骨质破坏中起着重要的作用。骨病分级对脊柱PCM的预后判断具有一定的临床意义。     

流体剪切力对MC3T3-E1细胞OPG、RANKL蛋白表达的实验研究

目的探讨流体剪切力(fluid shear stress,FSS)作用下,两种调节骨骼重建的重要分子骨保护素(osteoprotegerin,OPG)和细胞核因子κB受体活化因子配体(receptor activator of NF-κB ligand,RANKL)的蛋白表达情况。方法采用体外模型对MC3T3-E1细胞加载流体剪切力,细胞经不同时间加力后(0,30,60,90,120min),对细胞分别进行染色和裂解,运用免疫荧光和蛋白印迹法对OPG和RANKL的蛋白表达水平进行定量分析。结果 FSS作用30,60,90,120min后能够显著增加OPG的蛋白表达(P0.05),减少RANKL的蛋白表达(P0.05)。两者共同作用使得OPG/RANKL值显著增高(P0.05)。结论流体剪切力刺激提示OPG/RANKL的比值可能在成骨细胞和破骨细胞联合调节骨骼形成和吸收的过程中起着重要的调节作用。     

Smad4促进成骨分化的机制研究

目的 探讨Smad4基因促进成骨分化的作用机制。方法 采用条件性基因敲除技术Cre/loxp,制备骨细胞特异性敲除Smad4小鼠(Smad4otcko),小鼠胚胎骨骼透明染色分析胚胎期小鼠长骨生长状况;待小鼠成长至1月龄,X-ray检测突变小鼠与对照组小鼠的骨密度差异;静态骨组织形态学分析检测突变鼠及对照鼠的骨量变化、成骨细胞数量变化等差异;实时荧光定量PCR检测Smad4突变鼠股骨成骨细胞相关因子Runx2、ALP、OSX及OCN;破骨细胞TRAP染色分析Smad4突变鼠破骨细胞形态及数量变化;qPCR检测突变鼠股骨破骨吸收标志基因RANKL、OPG,并计算RANKL/OPG比率。结果 Smad4基因敲除小鼠在胚胎期未出现长骨生长异常。X线结果显示,1月龄时,与对照组小鼠相比,Smad4突变鼠的骨密度降低（P＜0.05）,静态骨组织形态学分析表明突变鼠松质骨减少,皮质骨变薄,骨小梁数量减少（P＜0.05）;Smad4突变鼠成骨细胞标志基因表达量显著降低,成骨细胞的数量明显减少（P＜0.05）;RANKL作为破骨吸收标志物表达上调、作为其拮抗剂的OPG表达量下调,RANKL/OPG比率增高（P＜0.05）。结论 Smad4基因通过促进成骨分化,降低破骨吸收从而来维持骨稳态。     

重组骨保护素（rhOPG)药物的研究现状及应用展望

破骨细胞分化因子(receptor activator nuclear factor kappa B ligand,RANKL)与骨保护素(osteoprotegefin,OPG)是调节破骨细胞分化和骨吸收功能的关键因子.RANKL是连接骨与免疫系统的破骨细胞生成因子,能刺激破骨细胞分化和发挥骨吸收功能;OPG作为RANKL的诱饵受体,能够阻止RANKL与RANK的结合,从而抑制破骨细胞的分化和激活.应用重组骨保护素OPG融合蛋白可以预防和治疗骨丢失类疾病,抑制牙周炎发病过程中牙槽骨吸收,并成为目前预防微重力相关的骨损失的最有希望的药物之一.笔者对重组人骨保护素(rhOPG)基因工程药物的研究现状进行了简要的综述.     

维持性血液透析患者血清骨保护素与肾性骨营养不良的关系

骨保护素（OPG）是近年来在肿瘤坏死因子受体超家族中发现的一种具有调控破骨细胞产生和活化作用的生物活性物质。它与核因子κB活化子受体配体（RANKL,亦称骨保护素配体OPGL）和核因子κB活化子受体（RANK）组成的分子调控系统是体内维持骨代谢平衡的重要分子机制。在正常的骨转化中成骨细胞表面表达RANKL．它与破骨细胞前体或破骨细胞表面的RANK结合后启动了信号转导，使破骨细胞增殖和活化．溶骨活动增强。同时成骨细胞分泌OPG，它与RANK竞争性的抑制RANKL使溶骨作用不致过度强烈。     

牛源乳铁蛋白对体外培养大鼠成骨细胞RANKL和OPG mRNA表达的影响

目的观察牛源乳铁蛋白对成骨细胞核因子κβ受体活化受体（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，分别观察不同浓度乳铁蛋白处理不同时间对成骨细胞RANKL／OPGmRNA表达的影响。采用半定量RT-PCR方法检测RANKL／OPGmRNA。结果乳铁蛋白呈时间和剂量依赖性地刺激大鼠成骨细胞OPGmRNA的表达，而抑制RANKLmRNA的表达，使RANKL／OPG值降低。结论乳铁蛋白通过调节成骨细胞RANKL／OPG的基因表达，从而抑制破骨细胞介导的骨吸收。     

The ratio of messenger RNA levels of receptor activator of nuclear factor kappaB ligand to osteoprotegerin correlates with bone remodeling indices in normal human cancellous bone but not in osteoarthritis.

The determinants of cancellous bone turnover and trabecular structure are not understood in normal bone or skeletal disease. Bone remodeling is initiated by osteoclastic resorption followed by osteoblastic formation of new bone. Receptor activator of nuclear factor kappaB ligand (RANKL) is a newly described regulator of osteoclast formation and function, the activity of which appears to be a balance between interaction with its receptor RANK and with an antagonist binding protein osteoprotegerin (OPG). Therefore, we have examined the relationship between the expression of RANKL, RANK, and OPG and indices of bone structure and turnover in human cancellous bone from the proximal femur. Bone samples were obtained from individuals with osteoarthritis (OA) at joint replacement surgery and from autopsy controls. Histomorphometric analysis of these samples showed that eroded surface (ES/BS) and osteoid surface (OS/BS) were positively associated in both control (p < 0.001) and OA (p < 0.02), indicating that the processes of bone resorption and bone formation remain coupled in OA, as they are in controls. RANKL, OPG, and RANK messenger RNA (mRNA) were abundant in human cancellous bone, with significant differences between control and OA individuals. In coplotting the molecular and histomorphometric data, strong associations were found between the ratio of RANKL/OPG mRNA and the indices of bone turnover (RANKL/OPG vs. ES/BS: r = 0.93, p < 0.001; RANKL/OPG vs. OS/BS: r = 0.80, p < 0.001). These relationships were not evident in trabecular bone from severe OA, suggesting that bone turnover may be regulated differently in this disease. We propose that the effective concentration of RANKL is related causally to bone turnover.     

Serum osteoprotegerin and renal osteodystrophy.

BACKGROUND: Numerous growth factors and cytokines are known to modulate bone turnover. An important, recently discovered complex involved in osteoclastogenesis is the osteoprotegerin/osteoprotegerin-ligand (OPG/OPGL) cytokine complex, which is produced by osteoblasts. Many factors, including parathyroid hormone (PTH), appear to affect bone turnover through this pathway. In this disorder, the role of the OPG/OPGL system in the pathogenesis of renal osteodystrophy, a disease with either low or high bone turnover, has not been investigated so far. METHODS: Thirty-nine chronic haemodialysis patients had bone biopsies, including histomorphometric and histodynamic examinations. In addition, the following serum biochemistry parameters were measured: serum OPG, intact PTH, PTH 1-84, total PTH, osteocalcin, total and bone alkaline phosphatases, 25-hydroxycholecalciferol and 1,25-dihydroxycholecalciferol. RESULTS: On average, serum OPG levels were above the normal range. They were lower in adynamic bone disease (ABD) patients, than in patients with predominant hyperparathyroidism (HP) or mixed osteodystrophy (MO). Significant negative correlations were found between serum OPG and PTH levels, and between serum OPG and parameters of bone resorption (ES/BS) and bone formation (ObS/BS and BFR/BS) in HP and MO patients with PTH values < or =1000 pg/ml. For intact PTH levels < or =300 pg/ml, serum OPG was significantly lower in the group with ABD than in those with HP or MO (P<0.05). CONCLUSION: In renal osteodystrophy the OPG/OPGL system is involved in the regulation of bone turnover induced by PTH. The determination of serum OPG levels could be of use in the diagnosis of low turnover bone disease, at least in association with PTH levels < or =300 pg/ml.     

骨保护素和骨保护素配体在人骨髓基质细胞向成骨细胞分化过程中的表达

目的研究骨保护素和骨保护素配体在人骨髓基质细胞向成骨细胞诱导分化过程中的表达情况，探讨其在骨重建过程中的调节作用。方法实验中采用梯度离心法和酶消化法分别获得人骨髓基质细胞和成骨细胞，并将骨髓基质细胞向成骨细胞方向诱导分化。通过形态学观察、生化指标检测、细胞染色和矿化结节测定等方法，确定骨髓基质细胞的功能状态和分化程度。采用RT-PCR和Westem blot方法，检测骨髓基质细胞向成骨细胞分化过程中骨保护素和骨保护素配体的表达情况。结果获得的骨髓基质细胞和成骨细胞生长状态良好，生化指标稳定。骨髓基质细胞分化后，碱性磷酸酶分泌明显增加，可以产生大量的矿化结节，具有成熟成骨细胞的表型特征。RT-PCR和Western blot检测，在骨髓基质细胞向成骨细胞分化过程中，骨保护素在mRNA和蛋白质水平的表达明显升高，而骨保护素配体的表达则逐渐下降。细胞中OPG mRNA表达在第21天时达到最大，约为未分化时水平的2．5倍。而OPGLmRNA表达减少为未分化时1／2；细胞中OPG的蛋白质表达水平提高约为未分化细胞的6倍。统计学分析，P〈0．01，差异有显著性。结论在人骨髓基质细胞向成骨细胞分化过程中，骨保护素表达逐渐升高而骨保护素配体表达显著降低，两者比值的逐渐增大，从而发挥促进骨形成，抑制骨吸收的作用，这可能是协调骨重建周期有序进行的重要机制之一。     

Serum OPG and RANKL levels before and after intravenous bisphosphonate treatment in Paget's disease of bone

Paget's disease of bone (PDB) is a focal disorder of bone remodeling characterized by increased osteoclast-mediated bone resorption. Even though increasing evidence indicates enhanced nuclear factor-kB (NF-kB) signaling as a common mechanism involved in PDB and other related disorders, few studies investigated circulating osteoprotegerin (OPG) and receptor of activator of NF-kB-ligand (RANKL) levels in PDB patients. In this study we explored the relationships between OPG or RANKL levels and bone turnover markers in a group of patients with PDB, before and after intravenous bisphosphonate treatment (pamidronate 60 mg). Both OPG and RANKL were markedly elevated in PDB patients with respect to control groups (healthy or osteoporotic postmenopausal women and elderly men) and were positively associated with bone turnover markers. Higher levels of these cytokines were observed in polyostotic than monostotic PDB cases. The ratio between RANKL and OPG was more than 3-fold higher in PDB patients than in controls. Interestingly, in the group of patients treated with pamidronate, we found an increase in OPG levels that become statistically significant after 3 and 6 months from treatment. A trend toward a decrease in RANKL levels after treatment was also observed. The RANKL/OPG ratio was significantly reduced after 3 and 6 months of therapy. In contrast, in patients classified as non-responders, OPG and RANKL levels after pamidronate infusion did not significantly differ with respect to pre-treatment values. Thus, the positive effect of amino bisphosphonates in the treatment of PDB may be due to either direct or indirect suppression of RANKL-induced bone resorption through decreased RANKL and increased OPG production.     

慢性肾衰竭患者血清骨保护素浓度与心脏瓣膜钙化的关系

目的探讨慢性肾衰竭（CRF）患者血清骨保护素（OPG）水平与心脏瓣膜钙化的关系。方法以75例CRF患者[非透析组（ND）25例,腹透组（PD）28例,血透组（HD）22例1和10例健康人（对照组）为研究对象,采用酶联免疫复合物法测定患者血清OPG水平,分析其与心脏瓣膜钙化之间的关系。结果各组CRF患者血清中OPG水平[ND组（4.77±1.74）μg/L、PD组（5.22±1.57）μg/L、HD组（5.35±1.72）μg/L]显著高于对照组[（2.04±0.57）μg/L,P〈0.01]。OPG水平与年龄（r=0.311,P〈0.05）和C反应蛋白水平（r=0.353,P〈0.01）呈正相关。根据有无心脏瓣膜钙化分组后发现,存在瓣膜钙化的CRF患者OPG水平较无瓣膜钙化组显著升高[（6.28±1.66）μg/L比（4.59±1.40）μg/L,P〈0.01]。Logistic回归分析显示血清OPG水平是CRF患者心脏瓣膜钙化发生的一项独立危险因素（P〈0.01）。结论在CRF患者中,血清OPG水平与心脏瓣膜钙化相关。     

血清骨保护素诊断前列腺癌骨转移的初步研究

目的探讨骨保护素（OPG）对前列腺癌骨转移的诊断意义。方法健康男性和前列腺增生患者各30例;对前列腺癌66例患者,分为无骨转移组（M0）36例（局限性前列腺癌30例、淋巴结转移6例）和骨转移组（M1）30例,采用ELISA法测定血清OPG浓度,结合临床资料进行统计学分析。结果M,组血清OPG浓度明显高于其他各组,差异有统计学意义（P〈0．001）。血清OPG与前列腺特异性抗原和碱性磷酸酶浓度呈正相关（r=0．427,0．277;P〈0．001）;与Gleason评分和病理分级呈正相关（r=0．331,0．344;P=0．001）。受试者工作特征（ROC）曲线分析可见,OPG的曲线下面积（AUC）较碱性磷酸酶大,对骨转移的诊断价值高。结论血清OPG对前列腺癌骨转移具有重要诊断价值。     

Imbalance of the osteoprotegerin/RANKL ratio in bone marrow microenvironment after allogeneic hemopoietic stem cell transplantation

BACKGROUND: Bone loss is a common complication after allogeneic stem cell transplantation. Osteoprotegerin (OPG) plays a critical role in bone remodeling by neutralizing the effect of receptor activator of nuclear factor-kappaB ligand (RANKL) on differentiation and activation of osteoclasts. We investigated OPG and RANKL in serum and marrow plasma in transplanted patients. MATERIALS AND METHODS: In 36 patients and 36 controls, the relationships among bone mineral density, circulating OPG, RANKL, interferon-gamma, and interleukin-6 levels were investigated; in addition, OPG and RANKL were measured in marrow plasma and in conditioned medium of long-term cultures of marrow mesenchymal-derived osteogenic cells. RESULTS: Lumbar and femoral bone mineral density were lower in patients than in controls (P<0.01). Serum OPG (sOPG) and interferon-gamma were significantly higher in patients than in controls (P<0.05). Patients' interferon-gamma correlated with sOPG levels (r=0.4; P=0.03). Interleukin-6 did not differ between patients and controls. By contrast, OPG levels were lower in patients than in controls in marrow plasma (P<0.001) and in conditioned media after one (P=0.035) and three months (P=0.003) of culture of marrow mesenchymal-derived osteogenic cells. RANKL was similar in patients and controls. The OPG/RANKL ratio "in situ" was significantly lower in patients than in controls (P<0.05). There was no correlation between sOPG and marrow OPG, RANKL levels, densitometric values, and chronic graft-versus-host disease. CONCLUSION: Our findings suggest that after allogeneic stem cell transplantation: 1) sOPG bear no relationship with OPG in the bone marrow; 2) increased sOPG can be the result of its enhanced production in extra bone tissues triggered by inflammatory cytokines; 3) low bone marrow OPG levels may be partly related to the persistent quantitative and qualitative deficit of osteoblastic precursors; and 4) reduced OPG/RANKL ratio in bone microenvironment may increase bone remodeling by promoting bone resorption.