植物雌激素对去卵巢大鼠骨质疏松性骨折愈合的影响

目的观察植物雌激素对卵巢去势大鼠骨折愈合过程中骨痂骨密度的影响。方法复制卵巢去势大鼠骨质疏松模型并制造股骨中段闭合性骨折,然后进行克氏针髓腔内固定,观察大鼠骨折内固定后骨痂与近骨痂段股骨骨密度的变化。结果异黄酮组、雌二醇组和假手术组骨痂的骨密度高于无用药组,差异具有统计学意义(P<0.05);而异黄酮组、雌二醇组和假手术组之间没有显著差别。结论植物雌激素能够显著提高骨质疏松大鼠骨痂及近骨痂段骨组织的骨密度、促进骨折愈合,与雌二醇组作用相近。     

仙灵骨葆对骨质疏松性骨折骨痂血管形成的影响

背景：骨质疏松对骨折愈合早期的影响尚存争议,仙灵骨葆对骨质疏松性骨折愈合的影响及其机制尚有待深入研究。 目的：观察骨质疏松对大鼠股骨干骨折愈合的影响,以及仙灵骨葆对骨质疏松性骨折愈合的作用。 方法：将50只雌性12周龄Sprague-Dawley大鼠随机分成5组：假手术组、骨折组、去卵巢组、去卵巢+骨折组及治疗组,后3组切除大鼠双侧卵巢制备去卵巢模型,骨折模型于去卵巢后4周制备,为股骨干中段横行骨折。治疗组在去卵巢及骨折基础上灌胃给予仙灵骨葆250 mg/(kg•d)。给药3周,取去卵巢+骨折组、骨折组和治疗组大鼠骨折侧标本行X射线摄像仪摄片后,测量其骨密度,苏木精-伊红染色观察骨痂组织的病理学改变并计数血管,免疫组织化学染色检测骨痂组织骨形态发生蛋白2的表达。 结果与结论：去卵巢处理后大鼠的骨密度、计算机X射线摄像仪摄片评分显著降低(P < 0.05),仙灵骨葆可在一定程度上提高去卵巢后骨折大鼠的骨密度及X射线摄像仪摄片评分,但差异无显著性意义(P > 0.05);仙灵骨葆可提高去卵巢后骨折大鼠骨痂组织的血管数量(P < 0.05),但对骨形态发生蛋白2的表达无影响。提示,去卵巢后大鼠骨折早期愈合过程延迟,仙灵骨葆可促进骨质疏松大鼠骨折愈合早期血管的形成。     

雌激素与辛伐他汀序贯法干预对去势大鼠骨质疏松的治疗作用

背景:Frost根据骨重建的概念创建了骨重建干预理论——序贯疗法,即在骨吸收抑制剂之后可给予刺激骨形成的药物。目的:基于骨重建干预理论,序贯应用雌激素与辛伐他汀干预骨重建吸收期和形成期,观察其对去势大鼠骨质疏松的治疗作用。方法:3月龄雄性SD大鼠40只,以随机数字表法分为去势组与正常对照组。去势组切除双侧卵巢,正常对照组只进行下腹部皮肤单纯切开术。大鼠去势后1个月,将去势组随机分为3组:序贯组、雌激素组、去势对照组,并开始药物干预:序贯组,皮下注射苯甲酸雌二醇0.1mg/kg,3d给药1次,2周后,灌胃给予辛伐他汀5mg/(kg·d)2周,停药5周,再应用辛伐他汀5mg/(kg·d)灌胃2周;雌激素组,皮下注射苯甲酸雌二醇0.1mg/kg,每3d给药1次,连续用药11周;去势对照组,单纯的饲料喂养,无药物干预。11周后,双能X射线骨密度仪测定股骨骨密度,放射免疫法检测血清白细胞介素6、骨钙素水平。结果与结论:各治疗组大鼠股骨骨密度、骨钙素水平高于去势对照组(P0.05),并且序贯组明显高于雌激素组(P0.05)。各治疗组白细胞介素6水平低于去势对照组(P0.05),并且序贯组低于雌激素组(P0.05)。说明雌激素和辛伐他汀序贯疗法可以通过抑制骨吸收,促进骨形成有效地治疗骨质疏松。     

降钙素促进骨质疏松骨床中植入体的骨整合

背景：降钙素具有提高骨量、骨质量,降低骨折发生的效果。 目的：评价鲑鱼降钙素对羟基磷灰石植入体骨整合的影响,及其在治疗骨质疏松症同时促进植入体生物学固定的能力。 方法：将SD大鼠随机分为假手术+羟基磷灰石棒组、卵巢切除+羟基磷灰石棒组、卵巢切除+降钙素+羟基磷灰石棒组,后2组建立绝经后骨质疏松动物模型。建模后分别在3组大鼠的胫骨平台处开孔植入多孔羟基磷灰石假体,卵巢切除+降钙素+羟基磷灰石棒组大鼠皮下注射鲑鱼降钙素12周。 结果与结论：卵巢切除后,大鼠的腰椎骨密度降低,而持续皮下注射鲑鱼降钙素后,大鼠的腰椎骨密度逐渐改善。应用降钙素处理后的大鼠,其骨结合率较卵巢切除+羟基磷灰石棒组提高了22.0%(P < 0.05)。结果证实,全身给予鲑鱼降钙素能提高骨质疏松大鼠骨床和植入体周围骨量、促进主体骨-植入体的骨整合。     

质子泵抑制剂FR167356对骨质疏松模型兔种植体骨整合的影响

背景：破骨细胞质膜上的空泡型质子泵是骨组织溶解必不可少的关键酶,空泡型质子泵抑制剂对体外培养的破骨细胞有明显的抑制作用。 目的：观察质子泵抑制剂FR167356对骨质疏松家兔种植体周围骨整合的影响。 方法：将24只5月龄雌性家兔随机分成单纯卵巢切除组、质子泵抑制剂组及假手术组,每组8只,前2组家兔切除双侧卵巢,假手术组只切除卵巢周围等量的脂肪组织。卵巢摘除12周后,在所有家兔的双侧胫骨近心端各置入1枚纯钛种植体(长8 mm,直径3.3 mm)。质子泵抑制剂组在种植体周围肌注FR167356,其他2组肌注等量的生理盐水。在种植后4,12周进行X射线片、组织形态学观察及拔出力学实验。 结果与结论：X射线片检查结果显示种植后第4周时,单纯卵巢切除组种植体的高阻射影像、种植体螺纹间隙的低密度影像、骨组织的界限明显比其他2组清楚;12周时,与单纯卵巢切除组相比,假手术组和质子泵抑制剂组种植体螺纹间隙的密度与周围骨组织更接近,种植体与周围骨组织的界限消失的更明显,2组无明显差异。组织学观察结果发现,4周时假手术组和质子泵抑制剂组种植体周围骨质多孔,平行于种植体表面的骨小梁排列紧密,小梁间连接较多,2组无明显差异;12周时假手术组和质子泵抑制剂组种植体周围骨组织量比4周时明显增加,骨小梁增粗且粗细均匀,连接紧密且间隙减小,单纯卵巢切除组没有观察到这种现象。在力学实验中,第4,12周,单纯卵巢切除组的最大拔出力值明显低于其他2组。提示局部应用质子泵抑制剂FR167356对骨质疏松家兔种植体骨整合有显著的促进作用。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接：     

大豆异黄酮干预去势大鼠骨密度及成骨细胞雌激素受体α的表达

背景：大豆异黄酮是一类植物雌激素,对绝经后骨质疏松症治疗具有重要意义。 目的：进一步验证大豆异黄酮对去势大鼠骨密度和成骨细胞雌激素受体α表达的影响。 方法：将12月龄去势雌性SD大鼠随机分为3组,大豆异黄酮组和对照组大鼠摘除双侧卵巢,假手术组只进行手术入路,不切除卵巢。大豆异黄酮组切除卵巢后,每日灌胃大豆异黄酮,连续40 d。对照组喂等量生理盐水。 结果与结论：喂饲40 d后对照组大鼠左侧股骨骨密度值显著低于假手术组(P < 0.05),提示骨质疏松模型成功。大豆异黄酮组大鼠左侧股骨骨密度高于对照组(P < 0.05);大豆异黄酮组雌激素受体α的表达量高于对照组(P < 0.05)。提示大豆异黄酮可增加去势大鼠骨密度,提高去势大鼠成骨细胞雌激素受体α的表达,促进成骨细胞增殖。     

骨质疏松性骨折愈合中骨改建的动态参数及骨密度变化

背景：当骨质疏松骨强度下降时,遭受轻微创伤或其他各种风险因素均易发生骨折。 目的：观察骨质疏松性骨折愈合过程中骨小梁组织学变化,骨密度及骨矿化沉积率的改变。 方法：SD大鼠随机分为骨质疏松组与对照组,骨质疏松组大鼠切除双侧卵巢,术后3个月,建立骨折模型。骨折后4,8,12,16 周,荧光显微镜下观察骨改建的动态参数,双能X线骨密度仪下测定骨痂组织的骨密度;骨折后1,2,4,6,8,12,16 周,应用自动图像系统测量骨组织形态。 结果与结论：骨质疏松组大鼠成熟小梁骨占骨痂面积比对照组小,且小梁骨厚度变薄、小梁骨间距较宽,骨质疏松组骨小梁表面荧光标记百分比及骨痂组织骨密度低于对照组;而骨矿化沉积率高于后者对照组。说明在骨质疏松性骨折愈合过程中,骨痂组织的组织学的异常改变导致骨折愈合质量的降低。     

雌激素干预骨质疏松大鼠牙槽骨改建过程中白细胞介素1的表达

背景：目前大鼠是骨质疏松研究中使用最多的模型动物,其中大鼠去卵巢动物模型应用最广泛,雌性大鼠在卵巢切除后,其骨质变化和给予雌激素后的反应与人相似。 目的：建立骨质疏松拔牙创愈合的大鼠动物模型,研究雌激素应用对骨质疏松大鼠牙槽骨中白细胞介素1分布及表达的影响。 方法：选用65只纯种3月龄雌性大鼠,按随机数字表法分为2组,骨质疏松模型组40只大鼠在全麻下摘除双侧卵巢,25只假手术组摘除卵巢周围与之大小相同的脂肪组织,常规饲养8周以建立大鼠骨质疏松模型。造模成功后全麻拔除大鼠左侧上颌磨牙,病理彩色图像分析仪分析颌骨变化。在骨质疏松模型组中随机抽取15只皮下注射苯甲酸雌二醇作为雌激素治疗组。免疫组织化学法观察白细胞介素1在各组大鼠拔牙后牙槽骨改建过程中的表达变化。 结果与结论：卵巢切除后,骨质疏松模型组大鼠的骨小梁薄而少,骨小梁间距变宽,颌骨骨强度下降。应用雌激素治疗后,发现雌激素治疗组白细胞介素1的阳性表达较骨质疏松组减少。提示3月龄SD雌性大鼠去卵巢8周后可发生骨质疏松,雌激素治疗对骨质疏松大鼠拔牙创骨愈合牙槽骨中白细胞介素1表达有明显的抑制作用。     

毛蕊异黄酮防治去卵巢大鼠骨质疏松的实验研究

目的复制去卵巢大鼠骨质疏松动物模型,观察不同剂量的毛蕊异黄酮对去卵巢大鼠骨质疏松的防治作用。方法 50只SD雌性大鼠,随机分成五组：设一假手术组;腹腔手术切除大鼠双侧卵巢,分为阴性对照组、毛蕊异黄酮低、高剂量组和雌激素对照组,分别给予标准饲料和不同剂量受试物,12周后进行骨密度、骨组织形态计量、生物力学测定,与雌激素对照,观察给与毛蕊异黄酮对绝经后骨质疏松的防治作用。结果大鼠去卵巢后骨密度显著下降,股骨的力学性能有较大变化,弯曲强度和弯曲弹性模量明显降低。给予毛蕊异黄酮后,可使骨密度显著提高（P〈0.01）,存在一定的剂量-效应关系,同时弯曲强度和弯曲弹性模量明显增加,但均低于雌激素对照组。结论通过去卵巢手术,成功建立绝经后骨质疏松动物模型;毛蕊异黄酮对去卵巢大鼠具有显著的骨保护效应,并存在一定的剂量效应关系,其作用弱于雌激素。     

微弧氧化/电化学沉积钙磷涂层纯钛种植体的骨内植入

背景：近年来已有对微弧氧化/电化学沉积技术制备涂层在材料性能方面的相关报道,但对这种材料植入体内的性能研究较少见。 目的：观察纯钛种植体经微弧氧化/电化学沉积处理后的骨结合和新骨形成情况。 方法：通过微弧氧化/电化学沉积方法在纯钛上制备含钙磷元素的涂层,然后将该种植体和纯钛种植体分别植入羊两侧胫骨种植窝内,于动物处死前15,5 d分别进行注射四环素进行四环素标记。术后4,12周分别进行X射线、扫描电镜及激光共聚焦观察。 结果与结论：两侧X射线表现相似,种植体周围均无明显阴影,骨小梁排列和骨质密度与宿主骨基本一致。术后4周时,在电镜下可观察到两组种植体和骨组织之间均有间隙,部分见骨性结合;术后12周时,微弧氧化/电化学沉积种植体组可形成新骨,并且新骨与种植体和原来骨组织结合紧密,涂层与钛基体没有明显间隙,纯钛种植体组也可见新骨生成,但可看到明显裂隙。激光共聚焦观察显示,微弧氧化/电化学沉积种植体组双标记带间距离及骨矿化沉积率均高于纯钛种植体组(P < 0.05)。表明微弧氧化/电化学沉积处理可增强纯钛种植体的骨结合能力及新骨形成。     

Effect of the difference of bone turnover on peri-titanium implant osteogenesis in ovariectomized rats

High and low bone turnover situations, both of which are typically observed as postmenopausal and senile osteoporosis, were created by ovariectomy (OVX), and then an investigation of whether or not the difference of bone turnover affected peri-titanium (Ti) implant osteogenesis in rats was conducted. Female rats were divided into four groups. The experimental and control groups underwent OVX or sham operations at 15 or 27 weeks of age, as high or low bone turnover groups, respectively. Ti implants were inserted into the tibiae at 30 weeks, then fluorochromes were injected 10 or 20 days after the implantation for histometry. The implants were retained for 30 days and then ground sections were prepared. Afterward, the cortical bone growth rate, bone contact ratio (BCR) of the implant in both the cortical bone area and medullary canal area, and the average trabecular bone thickness around the implant were evaluated. Biochemical markers of bone turnover were also measured. Biochemical measurements indicated both increasing osteocalcin production in OVX rats and decreasing tartrate-resistant acid phosphatase activity in the low-turnover group. Histometrical measurements showed decreasing cortical growth and low BCR in the medullary canal of the low-turnover group. The high-turnover group demonstrated BCR as high as that of the control group. There was no significant difference in the average trabecular bone thickness around the implant among the groups. As a result, two types of osteoporotic situations were confirmed and it was shown that the difference of bone turnover was clearly due to the diverse osteogenesis around the Ti implant.     

The effect of oxytocin on osseointegration of titanium implant in ovariectomized rats

Introduction: Oxytocin (OT) was reported to control differentiation of human mesenchymal stem cells and reverse osteoporosis (OP). This study investigated the effect of systematical treatment of OT on implant osseointegration in ovariectomized (OVX) rats. Material and methods: Twenty female rats received bilateral ovariectomy. Twelve weeks later, all animals were randomly assigned to control or experimental group. Each rat received two implants at the distal femoral metaphysis. From the first postoperative day, rats in experiment group received subcutaneous injection of OT (1 mg/kg · d), while animals in control group received vehicle. Twelve weeks after implantation, specimens containing implants were harvested and evaluated by histology, micro-CT, and push-out test. Tibiae were also harvested to evaluate the effect of OT on intact bone tissue of OVX rats. Results: Compared with control, OT treatment increased the relative bone volume surrounding the implant by 2.2 times, the percent implant osseointegration by 0.62 times, and the maximum push-out force by 2.25 times. Increased bone mass was also observed in histological sections of distal femur with implant and intact bone tissue of the proximal tibiae. Conclusion: Systemic administration of OT promoted peri-implant bone healing and osseointegration of titanium implant and recovered the negative effects of OP in undisturbed bone tissue partially.     

局部应用阿伦膦酸钠对非负荷期种植体骨结合影响的X射线观察*

背景：阿伦膦酸钠作为第3代二膦酸盐,具有很强的抑制骨吸收的能力。 目的：研究阿伦膦酸钠对非负荷期种植体周围骨结合的影响。 方法：取健康成年Beagle犬6只,随机等分为实验组和对照组,选取每犬的双侧下颌第二、四前磨牙共计24牙位,于实验第1,29,43,50天分别行即刻种植手术。实验组于种植体周围局部注射阿伦膦酸钠,对照组注射生理盐水,每周2次。 结果与结论：于实验第57天进行X射线显示种植体骨结合情况良好,实验组2周时即可见到种植体周围骨小梁的形成,明显早于对照组。提示阿伦膦酸钠可促进种植体周围骨组织中骨小梁的早期形成,从而影响种植体周围骨改建,提高非负荷期种植体周围骨结合。     

The effect of surface immobilized bisphosphonates on the fixation of hydroxyapatite-coated titanium implants in ovariectomized rats

Immobilized bisphosphonates (BPs) have been introduced to improve implant fixation, however, no information could be found about the efficiency of this approach in osteoporotic bone. This study was designed to evaluate the bone response to surface immobilized BPs on implants inserted in tibiae of ovariectomized (OVX) rats. Three months after bilateral ovariectomy, 40 rats were randomly assigned into four groups for implantation of hydroxyapatite-coated titanium implants with or without immobilized BPs: (1) control group (without BP treatments); (2) pamidronate (PAM) group (1 mg/ml of PAM immersing); (3) ibandronate group (1 mg/ml of ibandronate immersing); and (4) zoledronic acid (ZOL) group (1 mg/ml of ZOL immersing). After implantation periods of 3 months, the peri-implant–bone density, trabecular microstructure, bone–implant interface and mechanical fixation of implants were evaluated by dual energy X-ray absorptiometry, micro-computed tomography, histology and push-out test. We found that three BPs triggered pronounced bone–implant integration and early bone formation around implants in OVX rats, with a rank order of ZOL > ibandronate > PAM. These results provide new evidence that immobilized BPs have positive effects on implant fixation in osteoporotic bone, in addition to their well-documented potency to inhibit implant loosening in normal bone.     

Applications of micro-CT and MR microscopy to study pre-clinical models of osteoporosis and osteoarthritis.

There is a tremendous unmet therapeutic need for the treatment of osteoporosis and osteoarthritis. The ovariectomized rat and the guinea pig are widely used animal models for the evaluation of new therapeutics for osteoporosis and osteoarthritis, respectively. We have utilized X-ray micro-CT techniques to quantitatively evaluate the differences in trabecular bone in the rat proximal tibia following ovariectomy and treatment with estrogen (17-B-estradiol). Results demonstrate a loss of trabecular bone and architecture following ovariectomy (p < 0.001), and a marked inhibition of trabecular bone loss in the estrogen treated group (p < 0.001). A similar change in architecture can be visualized in images obtained by high resolution MR microscopy. In addition, a good correlation was observed between the values of trabecular bone fraction (BV/TV) in the rat tibiae as obtained from 3-dimensional micro-CT data and 2-dimensional static histomorphometry (r = 0.89, 0.73, 0.79 for sham, OVX, and treated groups, respectively). Micro-CT images were also obtained from a set of lumbar vertebrae from sham operated and ovariectomized rats. Significant bone loss can be measured as early as 8 weeks following ovariectomy (p < 0.005). Micro-CT and MR images were also obtained to study age related changes in the stifle joint of the guinea pig. Significant boney changes can be seen in the tibia and femur from the animals at various ages. Changes in cartilage and joint space can also be visualized in the images. The utility of micro-CT imaging in evaluating the mouse skeletal system is illustrated by obtaining morphological and architectural details from high resolution images of the mouse hind limb and proximal tibia, respectively. The results demonstrate the advantages that multi-dimensional imaging techniques can offer in evaluating bone and joint related changes in animal models of osteoporosis and osteoarthritis.     

Osseointegration of hydroxyapatite-coated and noncoated Ti6Al4V implants in the presence of local infection: a comparative histomorphometrical study in rabbits

A study was designed to investigate the osseointegration of titanium implants, either noncoated or coated with hydroxyapatite (HA), into rabbit tibiae in the presence of local infection compared with osseointegration in the absence of local infection. HA-coated or noncoated Ti cylinders were implanted into both tibiae of 32 rabbits (New Zealand Whites). Before implantation the left tibia was contaminated with different quantities of Staphylococcus aureus (10(2)-10(5) CFU). Four weeks after surgery the tibiae were explanted and prepared for microbiological and histomorphometrical examination. Histomorphometrical data, as a representation of implant fixation, were obtained by measuring the percentage of bone around the implants (within a radius of 1 mm from the outer diameter of the implants) and the percentage of the circumference of the implant that was in direct contact with bone. Histomorphometry revealed, in particular for the HA implants, a relationship between the inoculum concentration and/or the presence or absence of infection with the bone contact at the distal implant side. This confirms a relationship between peri-implant infection and bone contact or remodeling. HA-coated implants developed, in the presence of bacteria, more easily a more severe infection than noncoated Ti implants, and we show in the present study that local infection will influence histomorphometrical parameters (bone-implant contact) that determine implant fixation. Precautions to prevent contamination (asepsis) and/or infection (perioperative antibiotics) are even more important for the highly biocompatible HA-coated implant.     

雌激素对骨质疏松性骨折愈合过程BMP-4基因表达的影响

目的：研究雌激素对骨质疏松性骨折愈合骨形态发生蛋白-4（bone morphogenetic protein-4,BMP-4）基因定位分布的影响。 方法： 选用健康SD大鼠，随机分为卵巢切除（OVX）组、假手术对照（sham）组和雌激素替代治疗组（OVXE）。制成胫骨骨折愈合模型并分别于骨折后不同时点处死大鼠取材。通过光镜、电镜观察形态学和超微结构变化；采用原位杂交方法观察雌激素对BMP-4基因表达影响。 结果： (1)OVX组在骨痂形态及成骨细胞和破骨细胞活性与OVXE组比较有明显差异，较sham组差异更大。（2）骨折后1-3 d BMP-4 mRNA表达强度:sham组相似文献   

组蛋白去乙酰化酶在卵巢切除小鼠骨髓间充质干细胞中的表达

背景：骨髓间充质干细胞的多向分化能力在骨代谢疾病中发挥重要作用,受激素、细胞因子等多种因素调节。目前骨髓间充质干细胞骨向分化的表观遗传学调控机制尚不明确,组蛋白去乙酰化酶与骨质疏松的关系尚需进一步探讨。 目的：建立雌激素缺乏骨质疏松小鼠的实验动物模型,检测骨髓间充质干细胞组蛋白去乙酰化酶1,3,4 mRNA表达水平,探索卵巢切除小鼠骨组织形成障碍的表观遗传学机制。 方法：昆明种小鼠30只随机等分为模型组和假手术组。小鼠适应性喂养7 d后,模型组小鼠切除双侧卵巢,造成雌激素缺乏骨质疏松实验动物模型,假手术组小鼠仅切除等量脂肪组织。 结果与结论：模型组小鼠股骨骨小梁稀疏或断裂,骨小梁宽度变窄,骨小梁间距变宽,骨小梁占视野面积降低。与假手术组相比,模型组小鼠骨髓间充质干细胞中组蛋白去乙酰化酶3 mRNA表达水平显著降低,组蛋白去乙酰化酶1,4表达水平变化差异无显著性意义。提示雌激素缺乏导致骨髓间充质干细胞去乙酰化状态改变可能是骨形成障碍的重要原因之一。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：