龙胆苦苷通过MAPK信号通路对骨质疏松大鼠骨吸收的影响

目的 基于丝裂原活化蛋白激酶（MAPK）信号通路探讨龙胆苦苷（GENT）对骨质疏松（OP）大鼠骨吸收的影响。方法 78只雌性SD大鼠随机分为假手术组（Sham组）、模型组（OP组）、雌二醇组（E2组，0.05 mg/kg）、龙胆苦苷低（GENT LD，30 mg/kg）、中（GENT MD，60 mg/kg）、高剂量组（GENT HD组，120 mg/kg），除Sham组外大鼠均采用双侧卵巢切除术构建OP大鼠模型。ELISA检测血清骨代谢指标（CBF-α1、CTX-Ⅰ、PINP、OCE2）和炎性指标（IL-6、TNF-α、IL-1β）含量；三点弯曲测试评估右股骨机械强度；Micro-CT扫描大鼠右侧股骨观察股骨远端骨微结构变化；HE染色观察骨组织形态学变化；TRAP染色分析骨表面的破骨细胞数量（N.Oc/BS）；Western Blot检测骨组织RANKL和MAPK通路相关蛋白（JNK、ERK1/2、p38 MAPK及其磷酸化蛋白）的表达。结果 与Sham组相比，OP组大鼠血清E2、骨代谢相关标志物、股骨最大负荷和断裂挠度、BMD、骨小梁微结构参数BV/TV、Tb.N、Tb.Th显著降低（P＜0.05），炎症因子、Tb.Sp、N.Oc/BS、骨组织RANKL、p-JNK/JNK、p-ERK1/2/ERK1/2、p-p38/p38的表达明显升高（P＜0.05），骨皮质厚度和骨小梁数量明显减少，且骨小梁出现断裂，排列疏松；经GENT治疗后大鼠血清E2、骨代谢相关标志物、股骨最大负荷和断裂挠度、BMD、BV/TV、Tb.N、Tb.Th明显升高（P＜0.05），炎症因子、Tb.Sp、N.Oc/BS、骨组织RANKL、p-JNK/JNK、p-ERK1/2/ERK1/2、p-p38/p38的表达明显降低（P＜0.05），可见新生骨小梁，形态相对完整。结论 GENT可改善OP大鼠的骨微结构，对OP具有保护作用，其作用机制可能与抑制MAPK信号通路的激活，进而抑制破骨细胞的生成，减少骨吸收有关。     

蛇床子素骨靶向药物对体外培养大鼠成骨 细胞增殖功能的影响

目的观察以壳聚糖衍生物（NSC)为载体,与蛇床子素（OST)共价结合后形成的具有亲骨性 和亲水性的新型化合物一蛇床子素骨靶向药物（NSC-OST)对体外培养大鼠成骨细胞（Osteoblast ,OB) 增殖功能的影响,探讨其防治骨质疏松的作用机制。方法取新生大鼠颅盖骨进行OB分离、培养, 采用碱性磷酸酶（ALP)染色及茜素红染色法鉴定OB;随机将OB分为5组,即空白对照组及终浓度 为 10—7mmol/L、10 ―6 mmol/L、10-5 mmol/L、10 ―4 mmol/L NSC-OST 实验组,分别加人不同浓度的 NSC-OST作用不同时间,用MTT法检测成骨细胞增殖情况。结果体外分离培养的细胞具有典型成 骨细胞形态学及生物学活性,碱性磷酸酶、茜素红染色均呈阳性结果;作用M h、48 h时,终浓度为 10—5 mmolL NSC-OST 可显著促进 OB 增殖（P <0. 05 ),作用 72 h,终浓度为 10-6mmol/L 和 10-5 mmolLNSC-OST可显著促进OB增殖（尸<0. 05 );终浓度为10—4mmol/L NSC-OST具有明显抑制OB 增殖的作用（P<0.01 )。结论 NSC-OST的水溶性良好,理化性质稳定,适当浓度的NSC-OST可促进 成骨细胞增殖,有望成为有效抗骨质疏松作用的新型药物。     

防己诺林碱对去卵巢小鼠骨代谢及骨微结构的影响

目的探讨防己诺林碱对去卵巢小鼠骨质疏松的保护作用。方法将40只C57BL/6小鼠随机分为空白(假手术)对照组、模型(去卵巢)组、阳性(雌二醇,E2)对照组、防己诺林碱组共4组,每组10只。连续腹腔给药7周后处死小鼠,取股骨及外周血清,通过ELISA法检测骨代谢相关血清学指标:抗酒石酸酸性磷酸酶(TRAc P)、I型胶原羧基末端肽(CTX)及I型胶原氨基末端肽(NTX);通过Micro-CT评估各组小鼠骨组织微结构相关指标:骨小梁百分比(BV/TV)、骨小梁数量(Tb.N)、骨小梁分离度(Tb.Sp)和骨小梁厚度(Tb.Th);通过实时荧光定量PCR检测小鼠骨质疏松骨吸收相关基因的表达情况,包括TRAc P、组织蛋白酶K(Cathepsin K)、活化T细胞核因子1(NFATc1)以及降钙素受体(CTR)。结果与去卵巢模型组比较,防己诺林碱治疗组小鼠BV/TV、Tb.N、Tb.Th显著升高,Tb.Sp明显降低,骨代谢相关指标(TRAc P、CTX、NTX)显著降低,破骨细胞标志基因(TRAc P、Cathepsin K、NFATc1以及CTR)表达水平明显下降。结论防己诺林碱对去卵巢小鼠骨质疏松有保护作用,有望为骨质疏松的临床用药提供新思路。     

降钙素基因相关肽对大鼠骨髓单核巨噬细胞破骨分化作用的实验研究

目的 通过体外实验研究外源性降钙素基因相关肽（calcitonin gene-related peptide,CGRP)对大鼠骨髓单核巨噬细胞 (BMMs)破骨分化能力的影响,为CGRP在抗骨质疏松治疗方面的应用提供理论依据。方法 采用差速贴壁的方法分离出SD大鼠髓腔内单核巨噬细胞,原代培养并传代,在培养体系中添加含不同浓度CGRP (实验组：10–7 mol/L、10–8 mol/L、10–9 mol/ L;对照组：无CGRP)的破骨诱导液,对前体细胞进行破骨诱导7天后进行相关实验检测,分别采用抗酒石酸酸性磷酸酶染色(TRAP染色）观察破骨细胞的生成能力;用RT-PCR方法检测破骨细胞系特征性基因（RANK、TRAP、NFATc1); Western-blot检测破骨特征性TRAP和RANK蛋白的表达;骨磨片甲苯胺蓝染色检测诱导的破骨细胞的骨吸收功能。结果TRAP染色显示 CGRP各浓度组镜下成熟破骨细胞的个数显著低于对照组,有统计学差异(P <0.05)并随CGRP浓度的增高成熟破骨细胞数减少,CGRP组间亦差异明显(P <0. 05);RT-PCR检测破骨特征性RANK、TRAP、NFATc1 mRNA和Westem-blot测破骨特征性TRAP、RANK蛋白的表达各CGRP组均低于对照组(P < 0. 05);骨磨片破骨细胞甲苯胺蓝染色后单倍视野下CGRP组破骨陷窝数量也明显少于对照组(P < 0. 05),且与药物组浓度与陷窝数量呈负相关性。结论 CGRP能够抑制BMMs向破骨方向的分化,为CGRP抗骨质疏松的治疗提供理论支持。     

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。     

阿魏酸治疗对去卵巢雌性大鼠骨量流失的保护作用机制研究

目的研究阿魏酸(ferulic acid)对去卵巢大鼠骨量流失的影响,并探讨可能的机制。方法通过双侧去卵巢建立骨质疏松大鼠模型;随后随机分为假手术组(Sham)、去卵巢组(OVX)以及阿魏酸组,每组10只;其中阿魏酸组大鼠每天给予阿魏酸(20 mg/kg)灌胃治疗;待12周治疗结束后使用Micro-CT、HE染色切片、骨代谢指标、骨生物力学检测以及蛋白质印迹观察治疗效果以及探讨可能的机制。结果治疗12周后,与OVX组相比,Micro-CT和HE染色切片结果显示阿魏酸组的大鼠骨小梁数量和骨密度(bone mineral density,BMD)得到明显改善。阿魏酸组大鼠BMD、TV/BV、Tb.N、Tb.Th和Tb.Sp较OVX组明显改善(P<0.05)。治疗12周时,阿魏酸组极限载荷和刚度较OVX组显著增加(P<0.05),而阿魏酸组骨代谢指标P1NP和TRACP-5b水平显著降低(P<0.05),比较差异有统计学意义(P<0.05)。和OVX组比较,阿魏酸组BMP-2、Smad1、Smad4、p-Smad1/5/8表达水平上调,比较差异有统计学意义(P<0.05)。结论阿魏酸可以通过BMP2/Smads信号通路抑制去卵巢大鼠的骨量流失。     

曲古抑菌素A促进去卵巢大鼠钛植入物骨整合

目的 探讨TSA对去卵巢大鼠TI骨整合的影响。方法 将30只健康3月龄雌性SD大鼠随机分为Sham组（n=5）和OVX组（n=25）。正常饲养3个月后,两组各选取5只大鼠处死,取股骨远端样本行Micro-CT和HE染色以鉴定是否成功建立骨质疏松模型。随后在OVX组剩余大鼠双侧股骨干骺端植入直径1.5 mm TI,并将其分为2组：Control组（n=10）和TSA组（n=10）。连续给药4周。给药结束后处死全部大鼠并取股骨样本行Micro-CT扫描、HE染色以及Masson染色,ELISA法检测,拔钉实验。结果 与Sham组对比,Micro-CT显示OVX组BMD、BV/TV、Tb.Th、Tb.N降低（P<0.05）,而Tb.Sp、SMI升高（P<0.05）,HE染色显示OVX组骨小梁数量明显降低。与Control组对比,Micro-CT显示TSA组BMD、BV/TV、Tb.Th、Tb.N 、Conn.D均升高（P<0.05）,而Tb.Sp、SMI降低（P<0.05）,HE染色、Masson染色显示TSA组骨小梁数量、新生骨数量均升高,ELISA法检测结果显示TSA组OCN、BMP2均升高,拔钉实验显示TSA组TI轴向拔出力增大。结论 TSA通过上调OCN、BMP2等成骨相关蛋白,促进骨小梁形成和新骨形成,进而改善去卵巢大鼠TI骨整合。     

有机镓对去势大鼠骨代谢及骨量变化的影响

目的 观察有机镓对去势大鼠骨代谢及骨量变化的影响.方法 将30只大鼠随机分为假手术组、卵巢切除组和有机镓组.除正常对照组外,其他 2 组行卵巢切除.12周后假手术组、卵巢切除组给予PBS治疗,有机镓组给予有机镓干预.8周后取大鼠第五腰椎、股骨分别进行Micro-CT测定骨小梁组织结构;组织形态学测骨小梁占总骨量的百分数(BV/TV);生物力学测定股骨颈机械强度检查;生化指标检测比较血清TRAP、ALP、钙、磷.结果 Micro-CT测试表明有机镓组平均骨小梁厚度(Tb.Th)、皮质厚度Ct.Th)均明显高于卵巢切除组(P＜0.05),BV/TV明显高于卵巢切除组(P＜0.05),破骨细胞数显著减少,有机镓组股骨颈平均最大骨折负荷比卵巢切除组高27.4%,血清TRAP、钙、磷减少(P＜0.05).结论 有机镓减少骨吸收的同时增加骨形成,对于去势大鼠骨量减少有明显的改善作用.     

重组核因子κB活化因子受体蛋白预防小鼠骨质疏松的研究

目的:探讨一种原核表达的重组核因子κB活化因子受体蛋白对破骨细胞活性及去卵巢小鼠骨质疏松预防作用,并与目前临床应用最广泛的抗骨质疏松药物-阿伦磷酸钠进行疗效对比。方法:雌性KM小鼠24只,3月龄,卵巢切除造模后按体重随机分3组:重组核因子κB活化因子受体蛋白组(1.5mg/kg,2次/周),阿伦磷酸钠治疗组(0.21mg/kg,1次/周),对照组(PBS缓冲液,0.2ml,2次/周)。给药12周后,通过体重、血清钙、血清磷、血清碱性磷酸酶、骨组织TRAP染色破骨细胞计数及Micro-CT检查进行疗效评估。结果:给药12周后,对照组骨密度(BMD)(92.600±14.319)mg/cc,骨小梁厚度(Tb.Th)(0.094±0.011)mm,骨小梁间距(Tb.Sp)(0.455±0.124)mm,骨体积分数(BVF)0.192±0.023,结构模型指数(SMI)1.388±0.328;重组核因子κB活化因子受体蛋白组BMD(133.050±13.022)mg/cc,Tb.Th(0.098±0.009)mm,Tb.Sp(0.365±0.105)mm,BVF(0.291±0.025)%,SMI 0.661±0.384;阿伦磷酸钠治疗组BMD(128.013±16.040)mg/cc,Tb.Th(0.097±0.011)mm,Tb.Sp(0.376±0.104)mm,BVF 0.281±0.024,SMI 0.753±0.307。重组核因子κB活化因子受体蛋白能有效抑制去卵巢引起的骨质疏松,具有与阿伦磷酸钠同等效果。与PBS对照组相比,重组核因子κB活化因子受体蛋白治疗组股骨远端BMD增加明显,BVF增加,骨小梁结构致密,Tb.Th明显变宽,Tb.Sp变窄,SMI降低,股骨远端脱钙切片TRAP染色破骨细胞几乎完全被抑制。结论:在小鼠骨质疏松模型中,重组核因子κB活化因子受体蛋白具有阿伦磷酸钠同等疗效,能明显抑制破骨细胞的吸收活性,并预防去卵巢引起的骨量丢失。     

大黄素治疗对去卵巢大鼠骨量流失的保护作用机制研究

目的探讨大黄素(emodin,DHS)对去卵巢大鼠骨量流失的影响,并探索可能的机制。方法通过双侧去卵巢建立骨质疏松大鼠模型;随后随机分为假手术组(Sham)、去卵巢组(OVX)以及大黄素组(DHS),每组10只;其中DHS组大鼠接受大黄素[90 mg/(kg·d)]治疗12周;待治疗结束后使用Micro-CT、HE染色切片、骨代谢指标、以及蛋白质印迹观察治疗效果以及可能的机制。结果治疗12周后,与OVX组相比,Micro-CT和HE染色切片结果显示DHS组的大鼠骨小梁数量和骨密度得到明显改善。DHS组大鼠BMD、TV/BV、Tb.N、Tb.Th和Tb.Sp较OVX组明显改善(P<0.05)。与OVX组相比,DHS组的BALP水平明显升高(P<0.05);而TRACP-5b和β-CTX水平显著降低(P<0.05)。和OVX组比较,DHS组OPG表达水平上调(P<0.05),而RANKL和β2AR表达水平下调(P<0.05)。结论大黄素可以通过降低β2AR表达和激活OPG/RANKL信号通路介导对去卵巢大鼠骨量流失的保护作用。     

体外研究橙皮苷抑制钛颗粒介导的破骨细胞分化

目的研究橙皮苷对钛颗粒介导前破骨细胞分化及成熟的影响。 方法骨髓巨噬细胞在巨噬细胞集落刺激因子(M-CSF)30 ng/ml及核因子κB受体活化因子配体(Rankl)50 ng/ml刺激下,诱导分化为破骨细胞。扫描电镜观察钛磨损颗粒形貌结构。对不同浓度下橙皮苷对巨噬细胞增殖的影响进行t检验分析得出最低有效浓度;对抗酒石酸酸性磷酸酶(TRAP)阳性细胞数及骨吸收陷窝面积判断橙皮苷对破骨细胞分化及成熟的影响。最后通过实时定量PCR(RT-PCR)验证橙皮苷对钛颗粒介导的破骨基因,包括活化T细胞核因子(NFATc1)、组织蛋白酶K (CTSK)、TRAP的影响。TRAP阳性细胞数及骨吸收陷窝面积、RT-PCR结果数据均采用t检验分析。 结果扫描电镜显示钛磨损颗粒大小在1～3 μm。CCK-8实验结果显示橙皮苷对巨噬细胞增殖有促进作用,浓度超过40 μmol/L后,会对巨噬细胞产生抑制作用(F＝40.1, P<0.01),所以选择40 μmol/L作为对巨噬细胞分化的影响。在抗酒石酸酸性磷酸酶染色中发现40 μmol/L的橙皮苷会明显抑制前破骨细胞的分化,TRAP阳性细胞数目及破骨细胞的面积明显减少(t＝5.5,P<0.05)。与对照组相比,扫描电镜观察钛颗粒介导骨吸收陷窝面积明显增多,但加入40 μmol/L的橙皮苷后,这种吸收效果或明显减少(t＝6.1,P<0.05)。最后,通过RT-PCR实验得出,40 μmol/L的橙皮苷会明显抑制破骨细胞分化相关NFATc1, CTSK,TRAP基因(t＝7.1、4.8、9.1,均为P<0.05)。 结论橙皮苷抑制钛颗粒介导的破骨细胞分化及成熟。     

由“从瘀论治”理论探讨三七中槲皮素对破骨细胞分化自噬调控机制

目的 探究槲皮素对破骨细胞分化自噬调控机制的影响。方法 本实验分为对照组、RANKL组、RANKL+槲皮素组。通过CCK8检测摸索槲皮素的处理浓度，按照上述分组诱导7 d后进行TRAP染色验证模型成功后，加槲皮素干预48 h进行TRAP染色，通过qPCR检测TRAP、CTSK、NFATC-1、ATG5、p62、mTOR、Beclin-1基因表达。结果 根据CCK8结果选择槲皮素1 mg/L浓度；TRAP染色结果显示RANKL组破骨细胞显著增多，槲皮素干预后破骨细胞减少；qPCR 结果显示模型组TRAP、P62、CTSK、NFATC-1基因表达上升，ATG5、Beclin-1、mTOR基因表达下降，槲皮素干预组TRAP、CTSK、NFATC-1、ATG5、p62、mTOR、Beclin-1基因均下降。电镜观察显示槲皮素干预后破骨细胞自噬小体数量减少。结论 槲皮素可以通过降低自噬基因表达水平抑制破骨细胞的分化。     

Long-term effects of withdrawal of bisphosphonate incadronate disodium (YM175) on bone mineral density, mass, structure, and turnover in the lumbar vertebrae of ovariectomized rats.

This study was designed to evaluate the long-term effects of incadronate disodium (YM175) after its withdrawal on cancellous bone mass in ovariectomized (OVX) rats. Thirteen-week-old female SD rats were randomized into four groups: sham-operated, OVX, low-YM, and high-YM (0.01 mg/kg or 0.1 mg/kg subcutaneously [sc], three times a week after OVX) groups. After 4 weeks of treatment with vehicle or YM175, rats from each group were killed at time points of 0 (baseline), 3, 6, 9, and 12 months after withdrawal of the agent. Bone mineral density (BMD) of the lumbar vertebrae was measured by dual-energy X-ray absorptiometry (DXA). Bone volume (BV/TV), trabecular number and trabecular separation (Tb.N and Tb.Sp), eroded surface (ES/BS), osteoclast number and osteoclast surface (N.Oc/BS and Oc.S/BS), osteoid surface (OS/BS), and bone formation rate (BFR/BS) were measured as histomorphometric parameters of the fifth lumbar vertebra. BMD, BV/TV, Tb.N, and Tb.Sp in YM175-treated groups were maintained at the same level as in the sham group until 12 months after withdrawal in the high-YM group and until 3 months after withdrawal in the low-YM group. YM175 decreased both bone formative and resorptive parameters in histomorphometry. Serum bone-specific alkaline phosphatase (ALP) and urinary deoxypyridinoline at both doses of YM175 also showed a suppressive effect of this agent on bone turnover. These results indicate that YM175, after withdrawal, still maintains bone volume dose dependently by depressing bone resorption and formation in OVX rats. Intermittent YM175 treatment with a long interval may be sufficient to maintain the bone volume and structure in OVX rats.     

壮骨止痛方通过RANKL/RANK信号通路抑制骨吸收的机制研究

目的 探讨壮骨止痛方调控骨吸收及破骨活动干预去势大鼠骨质疏松症的疗效和作用机制,为临床治疗绝经后骨质疏松症提供实验依据。方法 40只SD大鼠按照完全随机原则分为ZGZTF组、EV组、OVX组、SHAM组。除SHAM组之外余下均按国内外常用PMOP模型构建方法造模。术后第7天分别给予中药、雌二醇和蒸馏水灌胃。末次取材后检测大鼠右侧股骨骨密度,HE染色法观察各组大鼠胫骨骨组织病理形态变化,ELISA检测血清E2、RANKL水平,免疫组化法分析RANK、TRAP、CTSK的蛋白表达。结果 与OVX组相比,ZGZTF组大鼠骨密度有所升高,胫骨股骨骨组织微结构得到改善,骨小梁连续性稍恢复,骨髓腔缩小,脂肪空泡减少。血清中E2表达上调,RANKL水平下调（P＜0.05）,骨组织RANK、TRAP、CTSK蛋白表达下调（P＜0.05）。结论 壮骨止痛方可以降低去势大鼠骨组织相关的破骨因子的表达。抑制破骨细胞过度分化,改善骨耦联失衡,达到治疗绝经后骨质疏松症的疗效。     

Expression of bone resorption genes in osteoarthritis and in osteoporosis

Cathepsin K and MMP-9 are considered to be the most abundant proteases in osteoclasts. TRAP is a marker for osteoclasts, and there is increasing evidence of its proteolytic role in bone resorption. RANKL is a recently discovered regulator of osteoclast maturation and activity and induces expression of many genes. This study compared cathepsin K, MMP-9, TRAP, RANKL, OPG, and osteocalcin gene expression in the proximal femur of patients with osteoarthritis with that of patients with femoral neck fracture. Fifty-six patients undergoing arthroplasty because of osteoarthritis or femoral neck fracture were included in the study. Total mRNA was extracted from the bone samples obtained from the intertrochanteric region of the proximal femur. Real-time RT-PCR was used to quantify CTSK (cathepsin K), MMP-9 (matrix metalloproteinase 9), ACP5 (TRAP), TNFSF11 (RANKL), TNFRSF11B (OPG), and BGLAP (osteocalcin) mRNAs. The levels of mRNAs coding for MMP-9 and osteocalcin indicated higher expression in the osteoarthritic group (P = 0.011, P = 0.001, respectively), whereas RANKL expression and the ratio RANKL/OPG were both significantly lower in the osteoarthritic group than in the fracture group. Expression of cathepsin K, MMP-9, and TRAP relative to RANKL was significantly higher in the osteoarthritic group. Ratios of all three proteolytic enzymes relative to formation marker osteocalcin were higher in the fracture group. Gene expression of cathepsin K, MMP-9, TRAP, RANKL, OPG, and osteocalcin and the association between their mRNA levels pointed to higher bone resorption and bone formation in osteoarthritis, differences in balance between them, and differences in regulation of bone resorption in osteoarthritic and osteoporotic bone.     

Trabecular bone turnover and bone marrow cell development in tail-suspended mice.

To clarify the relationship between the changes of trabecular bone turnover and bone marrow cell development during mechanical unloading and reloading, we performed experiments with tail-suspended mice. At 8 weeks of age, 150 male ddY mice were divided into three body weight-matched groups. Mice of group 1 were euthanized at the start of tail suspension (day 0) as a baseline control. The mice of group 2 were subjected to hindlimb unloading by tail suspension for 14 days and reloading for the subsequent 14 days. The mice of group 3 were normally loaded as age-matched controls. Mice of groups 2 and 3 were sacrificed at 7, 14, and 28 days after the start of the experiment. In the first experiment (histomorphometric study of tibiae), unloading for 7 and 14 days and reloading for the subsequent 14 days significantly decreased the bone volume compared with that in the age-matched controls, respectively. Unloading for 7 and 14 days also significantly reduced the bone formation rate (BFR/BS), respectively, but reloading for the subsequent 14 days restored BFR/BS to the control level. While the unloading for 7 and 14 days significantly increased both the osteoclast surface (Oc.S/BS) and the osteoclast number (Oc.N/BS), the reloading for the subsequent 14 days decreased Oc.S/BS and Oc. N/BS, respectively. In the second experiment (bone marrow cell culture study of tibiae), unloading for 7 and 14 days reduced the adherent stromal cell number, without significance. Unloading for 7 days significantly decreased the mineralized nodule formation. Reloading for the subsequent 14 days markedly increased the adherent stromal cell number and the mineralized nodule formation. Unloading for 7 days significantly increased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells. These data clearly demonstrate that unloading reduces bone formation and increases bone resorption, and subsequent reloading restores reduced bone formation and suppresses increased bone resorption, closely associated with the changes in adherent stromal cell number, mineralized nodule formation, and the number of TRAP-positive multinucleated cells.     

Relationship between the number of resorbing cells and the amount resorbed in metabolic bone disorders.

The relationship between bone-resorbing cells, assessed by the presence of tartrate-resistant acid phosphatases (TRAP) and morphologic indices of bone resorption, was determined in 29 osteoporotic patients (14 postmenopausal females and 15 males) and 15 dialyzed patients. The number of TRAP-positive cells per unit of cancellous bone area (N.Oc/B.Ar) was higher in dialyzed patients than in those with osteoporosis (16.8 +/- 15.3 versus 4.95 +/- 2.86, p less than 0.05). The amount of bone resorbed at the basic multicellular unit level was estimated by calculating eroded area containing TRAP cells per bone area (E.Ar+/BA). This novel parameter was similar in dialyzed and in osteoporotic patients (41,700 +/- 28,400 versus 32,300 +/- 24,600). In contrast, trabecular spacing (Tb.Sp) was identical in both metabolic bone diseases. Trabecular width (169 +/- 38 versus 127 +/- 32 microns, p less than 0.05) and bone area were higher in dialyzed than in osteoporotic patients. N.Oc/B.Ar was significantly related to E.Ar+/BA in dialyzed (r = 0.76, p less than 0.05) but not in osteoporotic patients. Tb.Sp was significantly correlated to N.Oc/B.Ar and to the number of TRAP-positive cell nuclei per B.Ar (r = 0.44, p less than 0.05) in osteoporotic but not in dialyzed patients. This last result shows that in overt osteoporosis with thin trabeculae, trabecular spacing is related to the number of resorbing cells. In contrast, the spacing of thick trabeculae in dialysis osteodystrophy is not dependent on the number of osteoclasts.     

大鼠去卵巢后骨髓源性破骨细胞形成的动态变化及其与骨髓IL-6、IL-6受体表达的关系

目的 观察大鼠去卵巢后骨髓源性破骨细胞形成的动态变化及其与骨髓细胞IL-6、IL-6受体以及gpl30基因表达水平改变的关系。方法 健康3月龄雌性SD大鼠60只,30只作为假手术对照组,30只经腹手术去卵巢。分别于去卵巢后2,4,6,8,12周取去卵巢组和对照组各6只大鼠骨髓细胞作细胞培养和提取RNA。培养的第6天分别作瑞氏-吉姆萨染色和抗酒石酸酸性磷酸酶(TRAP)染色,以胞核3个或3个以上以及TRAP(+)为破骨细胞标志,计数细胞数。骨髓细胞提取总RNA进行逆转录PCR。结果 术后2周去卵巢组破骨细胞形成数即多于对照组(P<0.05);第4-6周,去卵巢组破骨细胞形成达高峰,明显多于2周(P<0.01);去卵巢后的8周,较峰值下降,直至12周去卵巢组破骨细胞形成数仍高于对照组(P<0.05)。与破骨细胞的变化相对应,术后2周,骨髓细胞IL-6及IL-6RmRNA表达均明显增高(分别为P<0.01,P<0.05);第4周时,IL-6表达水平达到高峰,保持至第6周,IL-6R表达则在第6周达最高;第8周,IL-6、IL-6R基因表达水平较峰值下降,但直至第12周仍高于对照组。去卵巢后全程未见gp130基因表达水平有明显变化。结论 大鼠去卵巢后骨髓干细胞分化形成破骨细胞明显增加,呈时间相关动态过程,第6周达高峰,这一过程与骨髓细胞IL-6、IL-6R基因表达的动态变化一致,提示去卵巢后骨髓细     

白茅苷对去卵巢大鼠骨髓间充质干细胞功能和骨量的影响

目的观察白茅苷治疗去卵巢大鼠骨髓间充质干细胞功能和骨量的影响并初步探索可能机制。方法通过双侧去卵巢建立骨质疏松大鼠模型;随后随机分为假手术组(Sham)、去卵巢组(OVX)以及白茅苷组(BMG),每组10只;其中BMG组去卵巢大鼠每天给予白茅苷(20 mg/kg)灌胃治疗;待12周治疗结束后分离培养各组大鼠骨髓间充质干细胞(BMSCs),使用碱性磷酸酶(ALP)和茜素红(ARS)染色并使用蛋白质印迹检测BMP-2、Runx2、OPN、OCN、ALP和Col1蛋白表达;进一步使用Micro-CT和骨生物力学检测观察治疗效果。结果 OVX组大鼠BMSCs向成骨细胞分化后ALP和ARS染色阳性面积以及BMP-2、Runx2、OPN、OCN、ALP和Col1表达较Sham组明显降低(P0.05);而经过BMG治疗,BMG组大鼠BMSCs向成骨细胞分化后ALP和ARS染色阳性面积以及BMP-2、Runx2、OPN、OCN、ALP和Col1表达较OVX组明显增加(P0.05)。OVX组股骨最大载荷和弹性模量、BMD、BV/TV、Tb.N和Tb.Th较Sham组明显降低,而Tb.Sp则明显升高(P0.05)。BMG组左侧股骨最大载荷和弹性模量、BMD、BV/TV、Tb.N和Tb.Th均明显高于OVX组(P0.05),而Tb.Sp明显低于OVX组(P0.05)。结论白茅苷通过促进BMSCs诱导成骨分化来减少去卵巢大鼠骨骨密度、骨量和骨强度下降。