阿仑膦酸钠抑制破骨细胞体外吸收的研究

本研究利用体外分离培养的兔破骨细胞,观察第三代双膦酸盐阿仑膦酸钠（ａｌｅｎｄｒｏｎａｔｅ）对骨吸收的抑制作用。将ａｌｅｎｄｒｏｎａｔｅ加入培养液中使其最终浓度为０Ｍ,１μＭ,１０μＭ,１００μＭ。同时观察两组用ａｌｅｎｄｒｏｎａｔｅ盐溶液１００μＭ,５０μＭ浸泡的骨片对破骨细胞吸收功能的影响。用倒置光相差显微镜在不同时间点观察计数骨吸收陷窝并拍照。结果随着培养液内ａｌｅｎｄｒｏｎａｔｅ浓度增高,骨吸收陷窝数减少,面积亦减少。而用ａｌｅｎｄｒｏｎａｔｅ浸泡过的骨片上未见骨吸收陷窝。说明ａｌｅｎｄｒｏｎａｔｅ具有抑制破骨细胞体外骨吸收的作用。     

Taxol inhibits osteoclastic bone resorption

Summary We have examined the effect of the anti-tumor compound taxol, on osteoclastic bone resorption. In the bone slice assay, taxol (0.1–0.001 M) dose-dependently inhibited bone resorption with an IC₅₀ of 0.08 M. Osteoclast survival on bone slices was unaffected by 0.01–1 M taxol, but 10 M was cytotoxic. Taxol (1 M) also ihibited osteoclast spreading (45%) on fibronectin-coated slides. The antiproliterative effects of taxol are due to its unique ability to stabilize microtubules. Primary osteoclasts are nonproliferating end cells, so taxol probably inhibits bone resorption by intertering with other microtubule-dependent functions such as cell polarization, motility or vesicle exocytosis. Since these inhibitory effects on osteoclasts in vitro are seen with therapeutically relevant concentrations, taxol therapy may have beneficial side-effects e.g. inhibition of hyperealcemia and bone metastases.     

Doxycycline inhibits bone resorption by human interface membrane cells from aseptically loose hip replacements

Matrix metalloproteinases (MMPs) may have a role in the process of aseptic loosening. Doxycycline has been shown to inhibit MMPs. Our aim was to investigate the potential pharmacological effect of doxycycline on aseptic loosening. We used radiolabelled mouse calvariae cultured with human interface membrane cells from aseptically loosened hips. Bone resorption was confirmed in this model. The effect of doxycycline was assessed by culturing dead radiolabelled bone discs with cells from the interface membrane with doxycycline. The control group consisted of the same culture system without doxycycline. Supernatant 45calcium and the total 45calcium remaining in the bone discs at the completion of the culture were used to measure osteolysis. We found that doxycycline can inhibit osteolysis at the interface membrane of aseptically loosened hips. This may have therapeutic implications for the treatment of patients with aseptic loosening of total joint replacements.     

Alendronate inhibits periprosthetic bone loss around uncemented femoral components

Periprosthetic bone loss can be severe around the femoral component after uncemented arthroplasty. This study investigated the inhibitory effect of alendronate on periprosthetic bone loss. Seventeen patients underwent arthroplasty with an uncemented femoral component. Among them, 8 patients were given alendronate 5 mg once daily for 1 year (ALN group) and 9 patients received no pharmacotherapy (control group). Bone mineral density was measured in six periprosthetic zones by dual-energy X-ray absorptiometry at 1, 6, and 12 months after surgery. The average periprosthetic bone mineral density was 0.674–0.920 g/cm² at 1 month after surgery. From 6 months onward, the absolute bone mineral density and the ratio relative to the 1-month value were significantly decreased in the proximal zones of the femur in the control group (the ratio decreased from 0.817 to 0.769; P = 0.0040–0.0353). In the ALN group, however, the absolute and relative bone mineral density of the proximal femur remained unchanged for 12 months. In the other femoral zones, the absolute and relative bone mineral density remained unchanged throughout the study in both groups. We concluded that alendronate significantly inhibited the decrease of periprosthetic bone mineral density in the proximal femur after uncemented arthroplasty.     

Hydrochlorothiazide inhibits osteoclastic bone resorption In vitro

Long-term thiazide diuretic use is associated with higher bone mineral density and reduced hip fracture rates, which are attributed to increased serum calcium levels and decreased parathyroid activity that lead to decreased bone resorption. The present study shows that 1–100 M hydro-chlorothiazide (HCTZ) dose dependently inhibits bone resorption by isolated rat osteoclasts in the bone slice assay with an IC₅₀ of 20 M. At these concentrations, HCTZ did not affect osteoclast survival on bone slices and had no effect on the proliferation of UMR-106 rat osteoblasts, indicating that the compound is not cytotoxic. However, such concentrations of HCTZ are unlikely to be achieved in man where therapeutic doses are usually 12.5–100 mg/day. That the in vitro effect of HCTZ on bone resorption may be due to inhibition of osteoclast carbonic anhydrase is discussed.     

槲皮苷抑制RANKL诱导的破骨细胞形成及骨吸收

[目的]探讨槲皮苷对核因子κB受体激动剂配体(receptor activator of nuclear factor kappa B ligand,RANKL)诱导的破骨细胞形成及骨吸收功能的影响。[方法]通过CCK-8法观察不同浓度槲皮苷(0~800μmol/L)干预不同时间(48 h、96 h)对RAW 264.7细胞的生存影响,确定合适的体外用药浓度;利用体外RANKL诱导RAW 264.7细胞形成破骨细胞体系,通过抗酒石酸酸性磷酸酶(tartrate resistant acid phosphatase,TRAP)染色计数评价槲皮苷(200、400μmol/L)对破骨细胞形成和生存的影响;通过骨片吸收实验对骨凹陷和骨吸收面积统计分析评价槲皮苷(200、400μmol/L)3 d内对成熟破骨细胞骨吸收功能的影响;釆用实时定量(Real-Time)PCR技术,检测槲皮苷(200、400μmol/L)对RANKL诱导的破骨细胞特异性基因NFATc1、TRAP和c-fos表达水平的影响。[结果]细胞生存实验发现槲皮苷干预96 h后,槲皮苷(0~800μmol/L)对RAW 264.7细胞4 d内生存未发现显著影响;通过TRAP染色发现200、400μmol/L槲皮苷能显著抑制体外RANKL诱导的破骨细胞形成;通过骨片吸收实验发现200、400μmol/L槲皮苷3d内能显著降低骨吸收面积,提示其抑制成熟破骨细胞骨吸收功能;同时,槲皮苷能呈剂量依赖性抑制RANKL诱导活化T细胞核因子(nuclear factor of activated T cells,NFAT)c1、TRAP和c-fos基因表达。[结论]槲皮苷通过抑制NFATc1,TRAP和c-fos的表达,来抑制体外RANKL诱导的破骨细胞形成和骨吸收功能,是一种潜在治疗骨质疏松药物。     

Cortisol inhibits acid-induced bone resorption in vitro

Metabolic acidosis increases urine calcium excretion without an increase in intestinal calcium absorption, resulting in a net loss of bone mineral. In vitro, metabolic acidosis has been shown to initially induce physicochemical mineral dissolution and then enhance cell-mediated bone resorption. Acidic medium stimulates osteoblastic prostaglandin E(2) production, which mediates the subsequent stimulation of osteoclastic bone resorption. Glucocorticoids are also known to decrease bone mineral density, and metabolic acidosis has been shown to increase glucocorticoid production. This study tested the hypothesis that glucocorticoids would exacerbate acid-induced net calcium efflux from bone. Neonatal mouse calvariae were cultured in acid (Acid; pH = 7.06 +/- 0.01; [HCO(3)(-)] = 10.6 +/- 0.3 mM) or neutral (Ntl; pH = 7.43 +/- 0.01; [HCO(3)(-)] = 26.2 +/- 0.5 mM) medium, with or without 1 microM cortisol (Cort), and net calcium efflux and medium prostaglandin E(2) (PGE(2)) levels and osteoclastic beta-glucuronidase activity were determined. Compared with Ntl, Cort alone decreased calcium efflux, medium PGE(2), and osteoclast activity; Acid led to an increase in all three parameters. The addition of Cort to Acid led to a reduction of calcium efflux, medium PGE(2) levels and beta-glucuronidase activity compared with Acid alone. There was a significant direct correlation between medium PGE(2) concentration and net calcium efflux (r = 0.944; n = 23; P < 0.0001), between osteoclastic beta-glucuronidase activity and net calcium efflux (r = 0.663; n = 40; P < 0.001), and between medium PGE(2) concentration and beta-glucuronidase activity (r = 0.976; n = 4; P < 0.01). Thus, in vitro cortisol inhibits acid-induced, cell-mediated osteoclastic bone resorption through a decrease in osteoblastic PGE(2) production. These results suggest that the osteopenia observed in response to metabolic acidosis in vivo is not due to an increase in endogenous cortisol production.     

Alendronate did not inhibit instability-induced bone resorption. A study in rats

Alendronate is a bisphosphonate that can decrease osteoclastic activity. It has been suggested as treatment for periprosthetic osteolysis. We used 48 rats, of which 32 had a plate implant on one tibia, to study the effect of alendronate on bone resorption at an unstable implant-bone interface. The plate has a handle on top, which can be grasped through the skin and turned, to create a sliding motion of a titanium surface against the underlying bone. This is known to result in bone resorption, which was studied by histomorphometry. Osmotic minipumps were used to administer alendronate at 0.063 mg/kg/day or saline. The systemic effect of the treatment was assessed by ashing the proximal metaphyses of the tibia of the contralateral unoperated leg. The ash-weight was increased in the alendronate-treated group by 43% (p = 0.0001), corresponding to histological changes in the metaphyseal bone. There was no inhibition of the instability-induced bone resorption at the test surface by alendronate: bone was being resorbed and replaced by a tissue similar to a loosening membrane.     

Alendronate did not inhibit instability-induced bone resorption : A study in rats

Alendronate is a bisphosphonate that can decrease osteoclastic activity. It has been suggested as treatment for periprosthetic osteolysis. We used 48 rats, of which 32 had a plate implant on one tibia, to study the effect of alendronate on bone resorption at an unstable implant-bone interface. The plate has a handle on top, which can be grasped through the skin and turned, to create a sliding motion of a titanium surface against the underlying bone. This is known to result in bone resorption, which was studied by histomorphometry. Osmotic minipumps were used to administer alendronate at 0.063 mg/kg/day or saline. The systemic effect of the treatment was assessed by ashing the proximal metaphyses of the tibia of the contralateral unoperated leg. The ash-weight was increased in the alendronate-treated group by 43% (p = 0.0001), corresponding to histological changes in the metaphyseal bone. There was no inhibition of the instability-induced bone resorption at the test surface by alendronate: bone was being resorbed and replaced by a tissue similar to a loosening membrane.     

Promethazine inhibits osteoclastic bone resorption In vitro

Summary Several studies have shown that promethazine can reduce age-related osteopenia in mice. Furthermore, prolonged treatment with promethazine (50 mg/day) increases bone mineral content in the lumbar spine in post-menopausal women with osteopenia. However, the mechanism of action of promethazine has not been elucidated. The present study shows that promethazine HCl (0.01 – 10 M) dose-dependently inhibits bone resorption by isolated rat osteoclasts in the bone slice assay with an IC₅₀ of 1 M. Since these concentrations are likely to be achieved in vivo, it is suggested that the beneficial effect of promethazine on osteopenia is at least partly due to a direct inhibitory effect on osteoclast activity.     

Ibuprofen inhibits localized bone resorption in the middle ear

Summary Localized osteoclastic bone resorption plays a significant role in the pathogenesis of several diseases of the middle ear as well as orthodontic tooth movement and long bone remodeling. The mechanisms of control of localized bone loss and systemic bone resorption may be different but both may be mediated by a final common pathway which includes prostaglandins. Prostaglandins seem to have a predominantly stimulatory effect on bone resorption, although the exact mechanism is poorly understood. Ibuprofen, a nonsteroidal antiinflammatory drug, is known to inhibit the synthesis of prostaglandins. It is likely that ibuprofen, through its inhibition of prostaglandin synthesis, would decrease the localized osteoclastic bone resorption in a previously described animal model system. Mongolian gerbils were divided into three groups: low dose ibuprofen (10 mg/kg per day), high dose ibuprofen (30 mg/kg per day), and a control group. Following surgical implantation of catheters to the right bullae of each gerbil, pressure was applied for 8 days, stimulating osteoclastic bone resorption. After killing the animals and histomorphometric analysis of the bullae from each, comparisons were made between each group using osteoclast surface (percentage of bone area covered by osteoclasts), osteoclast number (number of osteoclasts/mm bone length), and osteoclast profile area (in μm²). Significantly lower osteoclast surface (Oc. S/BS) was found in pressurized bullae from both treatment groups when compared with pressurized bullae from controls (P<0.05) and significantly lower osteoclast number (N.Oc/T.L) in pressurized bullae from both treatment groups when compared with pressurized bullae from controls (P<0.05). These differences were found to be dose-dependent. No significant differences in individual osteoclast profile area were found in either treatment group when compared with controls.     

The radiographic classification of the bone-screw interface in paediatric tibial lengthening

Bone-screw loosening in monolateral external fixators is a significant problem. This study classifies the radiographic appearance of the bone-screw interface and predicts which screws will become loose and those that will remain solidly fixed to bone. Five radiographic features were identified at the bone-screw interface. The classification of these features was validated using interobserver and intraobserver studies. The reliability of the classification was improved by image enhancement with simple filters. Some radiographic features predicted which screws would eventually become loose, allowing the clinician to make earlier management decisions regarding the adjustment of screws.     

Cyclosporine A inhibits calcemic hormone-induced bone resorption in vitro

We have investigated the in vitro effects of cyclosporine (CsA), a potent immunosuppressive agent, on bone resorption induced by calcemic hormones. CsA inhibited parathyroid hormone (PTH), prostaglandin E2, 1,25-dihydroxy vitamin D3 (1,25(OH)2D3), and osteoclast-activating factor induced resorption of fetal rat limb bones in a dose-dependent manner. Established ongoing resorptive activity in bone was also inhibited by CsA. The CsA inhibition of bone resorption could be partially surmounted by higher concentrations of PTH and 1,25(OH)2D3. The inhibitory effects of CsA on limb bone resorption were reversible. Neither protein nor DNA synthesis were inhibited by treatment of limb bones with CsA. Thus, the inhibitory effect of this agent on bone resorption is not a cytotoxic one. These data could suggest that the induction of bone resorption by the calcemic hormones involves an immune cell derived mediator such as a lymphokine.     

椎弓根皮质骨螺钉固定与传统椎弓根螺钉固定钉道周围骨质CT值比较

目的 :比较椎弓根皮质骨螺钉固定与传统椎弓根螺钉固定钉道周围骨质的平均CT值,为椎弓根皮质骨螺钉的应用提供理论依据。方法:调取我院2014年1月~2016年10月21~70岁男女性腰椎高分辨率CT扫描影像资料,每10岁一个年龄组,单组随机抽取30例共300例数据。将各组数据导入Mimics 18.0中进行骨组织三维重建,在L4和L5椎体上模拟椎弓根皮质骨螺钉与传统椎弓根螺钉的置入,分割出各模拟螺钉与骨质相交的感兴趣区域并测量其平均CT值。结果:同年龄段同性别同种置钉方式L4、L5椎体感兴趣区域平均CT值均无统计学差异,皮质骨螺钉置钉与传统椎弓根螺钉置钉钉道周围感兴趣区域的平均CT值21~30岁组男性分别为547.4±48.2Hu和311.1±20.3Hu,女性为517.3±56.0Hu和279.1±41.7Hu;31~40岁组男性分别为519.6±48.9Hu和258.7±26.5Hu,女性为521.5±58.8Hu和287.8±33.2Hu;41~50岁组男性分别为490.9±69.8Hu和249.7±37.5Hu,女性为500.7±81.0和262.0Hu±72.1Hu;51~60岁组男性分别为436.5±65.7Hu和217.4±20.8Hu,女性为438.8±45.8Hu和222.1±22.6Hu;61~70岁组男性分别为396.1±40.0Hu和204.0±36.4Hu,女性为364.5±73.6Hu和153.5±27.1Hu;两种置钉方式各年龄组同性别间比较均有统计学差异(P0.05),皮质骨螺钉为传统螺钉的1.7~2.3倍。同种置钉方式不同性别间平均CT值比较,传统螺钉置钉在21~30岁、31~40岁和61~70岁组有统计学差异(P0.05);皮质骨螺钉置钉在21~30岁和61~70岁组有统计学差异(P0.05)。结论 :椎弓根皮质骨螺钉固定钉道周围骨质CT值明显高于传统椎弓根螺钉固定,椎弓根皮质骨螺钉固定具有更高骨-螺钉界面强度。     

A rat model of resorption of bone at the cement-bone interface in the presence of polyethylene wear particles

Resorption of bone and the formation of a membrane at the interface between acrylic cement and bone were induced by particles of high-density polyethylene that were similar in size to those that are present in the tissues surrounding a human joint prosthesis. A non-weight-bearing plug of methylmethacrylate was inserted through the knee joint into the distal part of the femur of the rat. The plug rapidly became surrounded by a shell of bone. After repeated injections of particles of high-density polyethylene into the knee joint, resorption of bone occurred at this stable interface. No resorption of bone occurred after the opposite knee was injected with a control preparation that did not contain particles. The resorption of bone that occurred around the plug after the injection of particles of polyethylene took place in the absence of mechanical causes for loosening and in the absence of infection.     

Alendronate increases bone density and bone strength at the distal radius in postmenopausal women.

In addition to the alendronate Osteoporosis Intervention Trial (FOSIT) core protocol 901-0A of 1908 enrolled patients, the use of peripheral quantitative computed tomography (pQCT) was explored for the assessment of response to therapy. Bone mineral and strength related parameters at two different sites at the distal radius were explored in a subset of the multicenter core study. One hundred and three patients were entered into the substudy and given either a daily dose of 10 mg of alendronate or placebo for 1 year. Measurements were done at months 0, 3, 6, and 12. Inclusion criteria were bone mineral density (BMD) measurements at the lumbar spine of -2 SD. The response to therapy was assessed by dual-energy X-ray absorptiometry in the lumbar spine and the hip, and by pQCT in the ultradistal and the shaft sites of the radius. In line with the FOSIT core study, alendronate increased BMD at the lumbar spine and the hip, and it decreased the serum biochemical markers of bone turnover. The substudy showed differences between the therapy and placebo group in trabecular bone density (8.4%, p = 0.095), in total density (6.8%, p = 0.009), and in the bone strength index (BSI) (15. 6 mm3, p = 0.037) at the ultradistal site due to treatment and no changes at the radius shaft. A significant correlation was observed between percentage changes from baseline in BMD of the lumbar spine, and in total density and bone strength at the ultradistal radius site in the treatment group, but not in the placebo group. Thus, the ultradistal radius site did respond to alendronate therapy. The increased bone density accompanied a significant gain in the BSI at the ultradistal site, a finding that might help explain the reduced wrist fractures in the alendronate Fracture Intervention Trial.     

Tibolone inhibits bone resorption without secondary positive effects on cartilage degradation

Background  

Osteoarthritis is associated with increased bone resorption and increased cartilage degradation in the subchondral bone and joint. The objective of the present study was to determine whether Tibolone, a synthetic steroid with estrogenic, androgenic, and progestogenic properties, would have similar dual actions on both bone and cartilage turnover, as reported previously with some SERMS and HRT.     

阿司匹林通过抑制大鼠破骨细胞 RANK 表达抑制骨质吸收

目的：研究不同浓度阿司匹林对体外培养大鼠破骨细胞（Osteoclast, OC）RANK（receptor activator of nuclear factor-κB,核因子κB受体活化因子）表达的影响。方法采用RANKL和M-CSF诱导大鼠骨髓单核巨噬细胞破骨分化模型,给予不同浓度的阿司匹林（0.25 mmol/L、0.5 mmol/L、1.0 mmol/L、1.5 mmol/L）和雌激素（雌二醇10-6 mmol/L）处理,而后进行抗酒石酸酸性磷酸酶（ The tartrate-resistant acid phosphatase ,TRAP）染色观察细胞形态特征,扫描电镜观察骨磨片破骨细胞骨吸收陷窝,RT-PCR技术检测破骨细胞表面RANK基因的表达,ELISA法检测RANK蛋白的表达。结果阿司匹林和雌激素都可以使大鼠破骨细胞成熟分化程度和骨吸收活性降低,抑制破骨细胞RANK基因和蛋白的表达,且阿司匹林的抑制作用具有剂量依赖性。结论阿司匹林对大鼠破骨细胞RANK的表达有抑制作用且呈剂量依赖性,从而抑制破骨细胞的成熟分化及骨吸收功能。