骨碎补提取液对体外分离破骨细胞性骨吸收的作用

目的 :研究骨碎补对体外分离破骨细胞性骨吸收的作用。方法 :体外分离出破骨细胞 ,与牛骨磨片共同培养 ,通过 Leica图像分析仪观察破骨细胞所形成骨吸收陷窝的数目与面积 ,反映破骨细胞性骨吸收情况。结果用 SPSS软件包分析。结果 :与空白血清组相比 ,2 0 %骨碎补提取液使骨磨片上形成的吸收陷窝数和面积从 ( 2 8.0 5± 2 .75 )个 /片和 ( 1 2 3 9.45± 5 2 3 .2 1 ) μm2减少到 ( 1 3 .2 0± 1 .2 6)个 /片和 ( 683 .1 7± 3 41 .3 8) μm2 ,空白血清组与 2 0 %骨碎补血清组比较差异具有显著性意义 ( P<0 .0 1 ) ,而 1 0 %低浓度骨碎补提取液对破骨细胞在骨磨片上形成的吸收陷窝数和面积从 ( 2 8.0 5± 2 .75 )个 /片和 ( 1 2 3 9.45± 5 2 3 .2 1 )μm2 减少到 ( 2 4.1 5±1 .1 2 )个 /片和 ( 82 3 .5 2± 5 2 7.1 8) μm2 ,二者比较无显著性意义 ( P>0 .0 5 )。结论 :骨碎补提取液对破骨细胞性骨吸收有抑制作用 ,但与浓度有关     

骨疏康对1型糖尿病大鼠体外培养的破骨细胞影响的初步探讨

目的 探讨骨疏康对1型糖尿病大鼠体外培养的破骨细胞影响。方法 用RANKL和M-CSF诱导1型糖尿病大鼠的股骨骨髓进行体外培养生成类破骨细胞样细胞(OLC)。实验分为正常对照组,1型糖尿病组,正常对照+骨疏康组,1型糖尿病+骨疏康组。骨疏康的浓度为20μg/ml。细胞培养7天后,贴壁细胞固定,抗酒石酸盐酸性磷酸酶染色,破骨细胞计数。结果 1型糖尿病大鼠与正常大鼠组的破骨细胞数比较无明显差别(P>0.05);经骨疏康干预后,1型糖尿病大鼠与正常大鼠的破骨细胞数都明显减少(P<0.01)。结论 1型糖尿病早期破骨细胞形成与正常对照组无明显差异。中药骨疏康明显抑制正常大鼠和1型糖尿病大鼠的破骨细胞形成。     

Rat Osteoclast Precursors In Vivo Express a Vitronectin Receptor and a Chloride-Bicarbonate Exchanger

In vivo osteoclast precursors, which are mononuclear, were previously found to express TRAP (tartrate-resistant acid phosphatase) and CTR (calcitonin receptor), like multi-nucleated osteoclasts. In vitro, they were found to express, in addition, VNR (vitronectin receptor) and CBE (chloride-bicarbonate exchanger). In order to ascertain that osteoclast precursors in vivo express VNR and CBE like their in vitro counterparts, we used immunohistochemistry to localize these molecules in developing long bones of neonatal rats. Frozen sections of metatarsals and phalanges of 1-2 day-old rats were stained for TRAP and mineralization using histochemistry or were reacted with polyclonal antibodies specific for either the β₃ chain of the VNR or synthetic sequences of the CBE. Both mature, multinucleated osteoclasts within the forming marrow cavity of metatarsals (as shown previously) and mononuclear osteoclast precursors located outside the bony collar of the phalangeal calcified rudiment (as shown here for the first time) expressed both TRAP, VNR and CBE. These findings suggest that mononuclear osteoclast precursors express many of the phenotypical markers of multinucleated osteoclasts prior to their fusion and multinucleation which may allow them to resorb bone, as suggested by in vitro observations of pit formation by preosteoclasts cultured on resorbable substances.     

False-Positive β-Galactosidase Staining in Osteoclasts by Endogenous Enzyme: Studies in Neonatal and Month-Old Wild-Type Mice

Escherichia coli β-galactosidase (β-gal), encoded by the lacZ gene, has become an essential tool in studies of gene expression and function in higher eukaryotes. lac-Z is widely used as a marker gene to detect expression of transgenes or Cre recombinase driven by tissue-specific promoters. The timing and location of promoter activity is easily visualized in whole embryos or specific tissues using the cleavable, chromogenic substrate, 5-bromo-4-chloro-3-indolyl-D-galactopyranoside (X-gal). The tissue specificity of promoters in transgenic constructs is routinely tested by using a promoter of choice to drive lacZ. Alternatively, the targeted expression of Cre recombinase to perform in vivo recombination of loxP sites can be visualized by β-gal staining in mice carrying a Cre-activated lacZ transgene, such as the ROSA26 strain. In the course of our investigations, we examined β-gal activity in bone tissue from genetically normal mice using standard detection methodology and found very high endogenous activity in bone-resorbing osteoclasts. This was true in frozen, paraffin, and glycol methacrylate sections. X-gal staining colocalized with the osteoclast marker, tartrate-resistant acid phosphatase (TRAP). β-gal activity was present in osteoclasts in long bones, in the mandible, and in both neonatal and more mature animals. We present this brief article as a caution to those testing genetic models of skeletal gene expression using β-gal as a marker gene.     

Multifunctional role of osteopontin in directing intrafibrillar mineralization of collagen and activation of osteoclasts

Mineralized collagen composites are of interest because they have the potential to provide a bone-like scaffold that stimulates the natural processes of resorption and remodeling. Working towards this goal, our group has previously shown that the nanostructure of bone can be reproduced using a polymer-induced liquid-precursor (PILP) process, which enables intrafibrillar mineralization of collagen with hydroxyapatite to be achieved. This prior work used polyaspartic acid (pASP), a simple mimic for acidic non-collagenous proteins, to generate nanodroplets/nanoparticles of an amorphous mineral precursor which can infiltrate the interstices of type-I collagen fibrils. In this study we show that osteopontin (OPN) can similarly serve as a process-directing agent for the intrafibrillar mineralization of collagen, even though OPN is generally considered a mineralization inhibitor. We also found that inclusion of OPN in the mineralization process promotes the interaction of mouse marrow-derived osteoclasts with PILP-remineralized bone that was previously demineralized, as measured by actin ring formation. While osteoclast activation occurred when pASP was used as the process-directing agent, using OPN resulted in a dramatic effect on osteoclast activation, presumably because of the inherent arginine–glycine–aspartate acid ligands of OPN. By capitalizing on the multifunctionality of OPN, these studies may lead the way to producing biomimetic bone substitutes with the capability of tailorable bioresorption rates.     

Tartrate-resistant acid phosphatase-positive cells in the synovial–cartilage junction and bone marrow during the progression of collagen-induced arthritis in adult rats

We investigated the time-course changes in bone destruction in rats with collagen-induced arthritis (CIA). The synovial–cartilage junction (SCJ) and epiphyseal bone marrow of the femoral posteromedial condyle in CIA rats were evaluated histologically and immunohistologically at 2, 3, 4, 6, and 8 weeks after sensitization. Two weeks after sensitization, tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells formed resorption lacunae on the lateral side of the cortical bone under the SCJ. No resorption lacunae were observed in bone marrow. Three weeks after sensitization, resorption lacunae on the lateral side of the cortical bone expanded, but no bone marrow invasion by pannus was observed. In bone marrow, many TRAP-positive multinuclear cells appeared and formed resorption lacunae in subchondral bone. Four weeks after sensitization, cortical bone was destroyed, and pannus had invaded the bone marrow. After six weeks, trabecular bone and subchondral bone plate were extensively resorbed by TRAP-positive cells. Bone destruction in CIA began with the appearance of TRAP-positive cells on the lateral side of the cortical bone under the SCJ, followed by the TRAP-positive multinuclear cells in bone marrow, which were morphologically unconnected to the SCJ lesions. These histological findings suggested that bone destruction in the early stage of arthritis occurred in two anatomically different regions.     

罗格列酮通过抑制RANKL及p-ERK活化抑制类风湿关节炎破骨细胞的分化及功能

目的:探讨罗格列酮(RSG)对类风湿关节炎(RA)成纤维样滑膜细胞(FLS)介导的破骨细胞(Oc)分化及功能的影响及其可能机制。方法:活动期RA患者滑膜体外分离培养FLS,与健康人外周血单核细胞(MNC)共培养,不同浓度RSG(0、5、10和15μmol/L)干预,抗酒石酸酸性磷酸酶(TRAP)染色鉴定Oc并计数;甲苯胺蓝染色和图像分析系统计算骨吸收陷窝面积;Real-time PCR检测共培养体系RANKL和OPG的mRNA表达,Western blot检测RANKL、OPG、p-ERK、p-p38和p-JNK的蛋白含量。结果:与不加RSG组比较,15μmol/L RSG干预后Oc的数量明显减少(P0.01),骨吸收陷窝面积也减少(P0.05);共培养体系RANKL的mRNA及蛋白表达明显降低,OPG的mRNA及蛋白表达明显升高(P0.01);p-ERK的蛋白含量明显降低(P0.05),p-p38及p-JNK的蛋白含量则不受影响。结论:RSG通过抑制RANKL及p-ERK活化影响RA关节微环境中组织细胞与免疫细胞的相互作用,从而抑制Oc分化及骨吸收功能。