Treadmill training regulates β-catenin signaling through phosphorylation of GSK-3β in lumbar vertebrae of ovariectomized rats

Postmenopausal osteoporosis is associated with high level of adipogenesis within the bone marrow at the expense of osteoblast population. The mechanical effect on β-catenin through phosphorylation of glycogen synthase kinase-3β (GSK-3β) is critical for inhibition of adipogenesis in mesenchymal stem cells in vitro. In present study, we hypothesized that treadmill training could regulate the β-catenin signaling through phosphorylation of GSK-3β in the lumbar vertebrae of ovariectomized (OVX) rats. 3-month-old female Sprague-Dawley rats were divided randomly into the following four groups: (a) Sham, (b) OVX, (c) OVX exercised (EX), and (d) OVX estrogen replacement (E(2)). At the end of the experiment, the serum levels of estradiol (E(2)) and luteinizing hormone (LH), the ultimate lumbar vertebra strength, as well as the protein expression for peroxisome proliferators-activated receptor γ (PPARγ), β-catenin, P-GSK-3β, and osterix (Osx) in lumbar vertebrae were analyzed. Moreover, the protein expression for β-catenin and P-GSK-3β were also examined in the uterus. The EX group had lower protein level of PPARγ, higher ultimate lumbar vertebral strength, and higher protein levels of β-catenin, and P-GSK-3β in lumbar vertebral bodies compared with sedentary OVX group. The effects of EX treatment on the protein levels of β-catenin and P-GSK-3β in bones were not reproducible in the uterus. Moreover, exercise treatment produced no estrogenic effect as evidenced by serum level of LH. In conclusion, this study suggested that treadmill training could activate the GSK-3β/β-catenin signaling and inhibit the production of PPARγ in lumbar vertebrae of OVX rats, which may contribute to the prevention of bone loss in OVX rats.     

酪蛋白激酶2相互作用蛋白1调控骨质疏松大鼠骨髓间充质干细胞的成骨能力北大核心

背景:目前对酪蛋白激酶2相互作用蛋白1(casein kinase 2-interaction protein-1,CKIP-1)分子机制的体外研究主要集中在基因敲除小鼠来源成骨细胞或骨髓间充质干细胞,鲜见报道骨质疏松模型大鼠来源骨髓间充质干细胞中CKIP-1表达的研究。目的:探讨下调CKIP-1基因前后骨质疏松状态骨髓间充质干细胞成骨分化能力的变化。方法:用维甲酸诱导雌性SD大鼠骨质疏松模型,采用全骨髓贴壁法体外培养骨质疏松组、正常组大鼠骨髓间充质干细胞。成骨诱导后进行茜素红染色、碱性磷酸酶染色及实时定量RT-PCR检测骨桥蛋白、Runx2 mRNA的相对表达,实时定量RT-PCR检测成骨诱导过程中2组细胞中CKIP-1的动态表达;通过基因转染沉默CKIP-1基因,成骨诱导后进行茜素红染色、碱性磷酸酶染色及实时定量RT-PCR检测骨桥蛋白、Runx2 mRNA的相对表达。结果与结论:①与正常组相比,骨质疏松组骨髓间充质干细胞茜素红染色钙结节定量、碱性磷酸酶活性及骨桥蛋白、Runx2的mRNA水平降低(P<0.05),骨质疏松组骨髓间充质干细胞中CKIP-1基因动态表达水平总体偏高;②与未下调CKIP-1的骨质疏松组骨髓间充质干细胞相比,下调CKIP-1基因表达后,骨质疏松组骨髓间充质干细胞茜素红染色钙结节定量、碱性磷酸酶活性及骨桥蛋白、Runx2的mRNA水平明显升高(P<0.05);③结果表明,维甲酸诱导的骨质疏松大鼠骨髓间充质干细胞成骨能力降低,下调CKIP-1基因可以部分提高其成骨分化能力。     

Retrovirus-mediated gene transfer of receptor activator of nuclear factor-kappaB-Fc prevents bone loss in ovariectomized mice

Postmenopausal osteoporosis is characterized by increased bone resorption due to estrogen deficiency. Receptor activator of nuclear factor-kappaB-Fc (RANK-Fc), a fusion protein that specifically blocks receptor activator of nuclear factor ligand binding to RANK, has been known to be efficient and well tolerated in animal models of osteoporosis. Here we show that cell-based gene therapy with RANK-Fc effectively prevented bone loss in ovariectomized (OVX) mice. Thirty-one young adult female C57Bl/6 mice were used, and repeated intraperitoneal injection of mesenchymal stem cells (MSCs) transduced with retrovirus was performed as follows: 1) Sham-operated mice (n = 8); 2) OVX mice treated with phosphate-buffered saline (OVX-PBS; n = 8); 3) OVX mice injected with MSCs transduced with control retrovirus (OVX-green fluorescent protein [GFP]; n = 7); and 4) OVX mice injected with MSCs transduced with RANK-Fc (OVX-RANK-Fc; n = 8). Cellular expression of RANK-Fc was confirmed by Western blot analysis of cell lysates and conditioned medium and also by enzyme-linked immunosorbent assay for the mice serum. Measurement of bone mineral density (BMD) by dual-energy x-ray absorptiometry (PIXImus) revealed that the OVX-RANK-Fc group gained significantly higher BMD than either the OVX-PBS group or OVX-GFP group after 8 weeks. The expression of GFP, which is coexpressed with RANK-Fc, was detected by polymerase chain reaction analysis of DNA isolated from femur and intra-abdominal fat, whereas no GFP signal was identified in liver, brain, heart, lung, or bone marrow aspirates. These suggest that expression of RANK-Fc by genetically modified MSCs may be a feasible option for the prevention of bone loss induced by ovariectomy.     

Comparative study of osteogenic differentiation potential of mesenchymal stem cells derived from bone marrow and adipose tissue of osteoporotic female rats

Osteoporosis causes reduction of osteogenic differentiation of mesenchymal stem cells (MSCs) from bone marrow and adipose tissue. This study was designed to compare the osteogenic potential of bone marrow mesenchymal stem cells (BMMSCs) and adipose-derived stem cells (ADSCs) of ovariectomized (OVX) rats. MSC were harvested from bone marrow and inguinal fat pads of six OVX rats. The limitations of this report are that cells from different animals were pooled for the purpose of the experiments that were carried out in this study. At 7, 14 and 21?d of osteogenic differentiation, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) conversion, alkaline phosphatase activity and gene expression for collagen I, osteocalcin, bone sialoprotein, osteopontin and bone morphogenetic protein-2 bone morphogenetic protein-2 (BMP-2) were analyzed. At 21?d, percentage of cells per field and percentage of mineralized nodule were analyzed. The data were subjected to analysis of variance, and the means were compared by Student–Newman–Keuls test. The cells, regardless of group, showed phenotypic characteristics consistent with stem cells. MTT conversion, alkaline phosphatase activity, percentage of mineralized nodule and expression of collagen I, osteocalcin and BMP-2 of ADSCs from OVX rats were higher when compared to BMMSCs from OVX rats in at least one of the evaluated periods (p?p?相似文献   

去势大鼠骨量丢失过程中骨髓间充质干细胞的增殖分化功能

目的: 研究骨髓间充质干细胞(BMSCs)增殖分化功能在去势大鼠骨质疏松发病过程中对骨量丢失的作用。方法: 选用10周龄健康雌性SD大鼠行双侧卵巢切除术(OVX),建立骨质疏松症(OP)的动物模型;选用同一批次、周龄相同、体重相近的健康雌性SD大鼠行双侧卵巢附近脂肪组织部分切除术,建立假手术(sham)组,假手术大鼠组(sham group)。采用离心法、贴壁法和有限稀释法分离、培养、纯化大鼠BMSCs,体外培养传至3~4代后用于实验:流式细胞术进行BMSCs表型鉴定;克隆形成实验检测BMSCs增殖状况;MTT法测定BMSCs生长曲线;成脂诱导后脂滴油红O染色法检测比较2组大鼠BMSCs成脂能力;成骨诱导后钙化结节茜素红染色法检测比较2组大鼠BMSCs成骨能力;RT-PCR法检测大鼠BMSCs成骨相关蛋白Runx2、骨钙素(OCN)和骨桥蛋白(OPN)mRNA的表达。结果: 与sham组大鼠BMSCs相比,OVX组大鼠BMSCs克隆形成能力减弱,增殖能力降低,成脂向分化增强,成骨向分化减弱(P<0.05)。结论: 去卵巢骨质疏松大鼠BMSCs增殖及成骨分化减弱,成脂分化增强;这导致去势大鼠快速的骨量丢失,在去势大鼠OP发病过程中发挥着重要作用。     

去卵巢骨质疏松大鼠骨髓间充质干细胞的体外成骨诱导

背景：细胞学研究表明,骨髓间充质干细胞在绝经后骨质疏松症的发病过程中起有重要作用。 目的：观察去卵巢骨质疏松大鼠骨髓间充质干细胞的体外成骨分化。 方法：将6月龄雌性SD大鼠双侧卵巢切除建立骨质疏松模型。实验分为4组：正常干细胞组、骨质疏松干细胞组、正常干细胞成骨诱导组、骨质疏松干细胞成骨诱导组。全骨髓贴壁法培养正常和骨质疏松大鼠骨髓间充质干细胞至第3代细胞用于实验。倒置相差显微镜观察细胞形态,流式细胞仪测定细胞周期、增殖指数。加成骨诱导液进行成骨诱导,检测各组骨髓间充质干细胞碱性磷酸酶活性,茜素红染色法比较各组钙结节的形成。 结果与结论：正常干细胞成骨诱导组、骨质疏松干细胞成骨诱导组均具有成骨细胞的形态特征,但骨质疏松干细胞成骨诱导组形态变化相对缓慢。正常干细胞组细胞增殖指数高于骨质疏松干细胞组(P < 0.05);成骨诱导组碱性磷酸酶活性均明显高于相应的正常或骨质疏松干细胞组(P < 0.05);正常干细胞成骨诱导组明显高于骨质疏松干细胞成骨诱导组(P < 0.05)。成骨诱导组茜素红染色均呈阳性,相应的正常或骨质疏松干细胞组呈阴性;且正常干细胞成骨诱导组染色强于骨质疏松干细胞成骨诱导组。提示去卵巢骨质疏松大鼠骨髓间充质干细胞的增殖能力和成骨分化能力明显降低,可能与去卵巢大鼠骨质疏松的发生相关。     

The use of autologous enriched bone marrow MSCs to enhance osteoporotic bone defect repair in long-term estrogen deficient goats

Bone defects are common in elderly patients suffering from osteoporosis. Current methods of bone defect treatment for osteoporosis are not always satisfactory. In this study, we demonstrated that bone marrow mesenchymal stem cells (MSCs) harvested from goats with long-term estrogen deficiencies exhibited a lower proliferation rate and decreased osteogenic capacity, which are critical obstacles for bone defect repair in the elderly. However, by combining autologous enriched bone marrow mesenchymal stem cells with porous β-TCP, we successfully repaired critical-sized bone defects in the medial femoral condyle of the osteoporotic goats. Both micro-CT images and histomorphometry analysis illustrated improved bone formation following the enriched MSC therapy. Thus, we proposed autologous enriched bone marrow mesenchymal stem cells as a quick, safe therapeutic strategy to treat osteoporotic bone defects.     

Selective osteogenesis by a synthetic mineral inducing peptide for the treatment of osteoporosis

Mineralization in mammalian cells is accomplished by concerted regulation of protein-based extracellular matrix (ECM) components, such as non-collagenous proteins and collagen fibrils. In this study, we investigated the ability of a collagen-binding motif (CBM) peptide derived from osteopontin to selectively affect osteogenic or adipogenic differentiation in vitro and in vivo. In particular, increased osteogenic differentiation and decreased adipogenic differentiation were observed in human mesenchymal stem cells (hMSCs). Osteocalcin (OCN) protein expression in MC3T3-E1 cells without osteogenic inducers was then investigated following treatment with the CBM peptide. In ovariectomized (OVX) mice, estrogen deficiency induced osteoporosis and increased fat tissue deposition. However, after the CBM peptide or estradiol was injected into the OVX mice for 2 months, the increased serum OCN concentration and alkaline phosphate (ALP) activity were decreased in the estradiol-treated group (OVX-E) and the high-concentration CBM peptide-treated group (OVX-HP). Significant bone loss was also observed in the ovariectomized mice (OVX-PBS). In particular, the bone volume per total volume (BV/TV) and bone mineral density (BMD) were significantly decreased in the OVX mice; however, both of these markers were restored in the OVX-HP group, which also had significantly well-developed bone structure and bone formation. In contrast to the bone structural change, adipose tissue was increased in the OVX-PBS. However, a significant decrease in total fat and subcutaneous fat was observed in the low-concentration CBM peptide-treated group (OVX-LP) and the estradiol-treated group (OVX-E). Taken together, these results suggest that the CBM peptide could be an effective therapeutic agent for osteoporosis due to its selective stimulation of osteogenic differentiation, rather than adipogenesis.     

Suppression of zinc finger protein 467 alleviates osteoporosis through promoting differentiation of adipose derived stem cells to osteoblasts

Osteoblast and adipocyte are derived from common mesenchymal progenitor cells. The bone loss of osteoporosis is associated with altered progenitor differentiation from an osteoblastic to an adipocytic lineage. In this study, a comparative analysis of gene expression profiling using cDNA microarray and realtime-PCR indicated that Zinc finger protein 467 (Zfp467) involved in adipocyte and osteoblast differentiation of cultured adipose derived stem cells (ADSCs). Our results showed that RNA interference for Zfp467 in ADSCs inhibited adipocyte formation and stimulated osteoblast commitment. The mRNA levels of osteogenic and adipogenic markers in ADSCs were regulated by si-Zfp467. Zfp467 RNAi in ADSCs could restore bone function and structure in an ovariectomized (OVX)-induced osteoporotic mouse model. Thus Zfp467 play an important role in ADSCs differentiation to adipocyte and osteoblast. This has relevance to therapeutic interventions in osteoporosis, including si-Zfp467-based therapies currently available, and may be of relevance for the use of adipose-derived stem cells for tissue engineering.     

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.     

雌激素缺乏导致的骨质疏松发病过程中骨髓间充质干细胞FasL表达降低对CD4+T淋巴细胞凋亡的影响

 目的：研究雌激素在骨质疏松发病过程中导致骨髓间充质干细胞（BMMSCs）Fas配体（FasL）表达降低对CD4+T淋巴细胞凋亡的作用。方法：选用8周龄健康雌性小鼠行双侧卵巢切除术(OVX),建立绝经后骨质疏松模型。选用同一批次周龄相同、体重相近的健康小鼠行双侧卵巢附近脂肪组织部分切除,建立假手术组（sham）,Micro-CT确定模型成功建立。流式细胞术对BMMSCs行表型鉴定,将OVX组、sham组和sham+雌激素刺激组BMMSCs与激活的T淋巴细胞共培养,以Annexin V/7-AAD/CD4流式细胞仪计数3组共培养体系中CD4+T淋巴细胞的凋亡差异,用实时荧光定量PCR和Western blotting检测OVX组、sham组及不同浓度雌激素刺激BMMSCs后FasL的表达情况。结果：流式检测显示sham+雌激素刺激组CD4+T淋巴细胞凋亡程度大于sham组(P<0.05),sham组CD4+T淋巴细胞凋亡程度大于OVX组(P<0.05),实时荧光定量PCR及Western blotting显示OVX组FasL mRNA及蛋白水平表达都较sham组低。在一定范围内不同浓度雌激素刺激下的sham组BMMSCs中FasL mRNA及蛋白表达与雌激素浓度呈梯度上升。结论：雌激素能够调控BMMSCs中FasL的表达,雌激素调控BMMSCs表达FasL能够影响CD4+T淋巴细胞凋亡的改变,这可能与绝经后骨质疏松发病相关。     

骨形态发生蛋白2抑制骨髓间充质干细胞成脂分化的优选浓度

BACKGROUND:Bone morphogenetic protein 2 cannot only promote osteogenesis, but also at different concentration ranges regulate the differentiation of bone marrow mesenchymal stem cells into adipocytes. Therefore, it is very important for the prevention and treatment of osteoporosis, if the range of concentrations of bone morphogenetic protein 2 can be found to regulate the differentiation of bone marrow mesenchymal stem cells into adipocytes, after the induction of bone marrow mesenchymal stem cells. OBJECTIVE:To determine the optimal concentration of bone morphogenetic protein 2 to inhibit the differentiation of bone marrow mesenchymal stem cells into adipocytes. METHODS:Bone marrow samples were obtained from the femur and tibia of rats. Primary cultured bone marrow mesenchymal stem cells were obtained by adherent culture method in vitro. Flow cytometry was used to identify the surface antigens of passage 2 bone marrow mesenchymal stem cells. Cells at passages 2 and 3 were taken and cultured in adipogenic induction medium for 3 days followed by the addition of 0.5, 5, 50, 100, 200 μg/L bone morphogenetic protein 2, or culture medium of bone marrow mesenchymal stem cells (control group), respectively. RESULTS AND CONCLUSION: Bone marrow mesenchymal stem cells cultured were identified by the flow cytometry. Oil red O staining results showed that the increasing number of lipid droplets was shown in bone marrow mesenchymal stem cells induced by bone morphogenetic protein 2 under the increasing concentration of 0.5 to 50 μg/L; while the number of lipid droplets in bone marrow mesenchymal stem cells decreased after 17 days of induction with bone morphogenetic protein 2 under the concentration of 100 to 200 μg/L. These findings indicate that 100 μg/L bone morphogenetic protein 2 can inhibit adipogenic differentiation of bone marrow mesenchymal stem cell, so as to reduce the formation of adipocytes in rats. Therefore, 100 μg/L bone morphogenetic protein 2 is better to inhibit adipogenic differentiation of bone marrow mesenchymal stem cells.     

骨髓间充质干细胞干预治疗骨质疏松症中的骨组织生物力学性能

目的以雷洛昔芬干预治疗骨质疏松为对照,用生物力学性能指标验证骨髓间充质干细胞(bone mesenchymal stem cells,BMSCs)干预治疗骨质疏松动物的效果。方法取6月龄雌性SD大鼠88只,随机分为骨质疏松动物模型组22只,正常对照组22只,雷洛昔芬干预组22只,骨髓间充质干细胞干预组22只。以摘除大鼠卵巢的方法建立骨质疏松动物模型。动物饲养4周后,分别以骨髓间充质干细胞和雷洛昔芬对骨质疏松动物进行干预治疗。于给药6周后检测各组大鼠血清Ca、P、碱性磷酸酶(alkaline phosphatase,ALP),并取胫骨进行剪切实验,取股骨进行冲击实验,测试肱骨的骨密度(bone mineral density,BMD)。结果骨髓间充质干细胞干预组肱骨BMD,血清Ca、ALP,胫骨各项剪切力学性能指标和股骨各项冲击力学性能指标大于模型组及雷洛昔芬干预组,其血清P小于模型组及雷洛昔芬干预组(P<0.05)。结论骨质疏松动物通过以骨髓间充质干细胞干预后,肱骨BMD,血清Ca、ALP,骨的强度和韧性可以得到一定恢复。     

调控骨髓间充质干细胞成骨分化的Wnt/β-catenin信号通路及相关因素

背景:骨髓间充质干细胞诱导成骨而抑制成脂分化是骨质疏松症防治的关键,也是骨组织修复工程种子细胞的来源,Wnt信号通路对骨形成起着重要作用.目的:综述Wnt/β-catenin信号通路调控骨髓间充质干细胞成骨分化的相关因素及分子机制.方法:应用计算机检索CNKI、PubMed及万方医学数据库建库至2020年2月发表的相关...     

骨髓间充质干细胞移植治疗骨质疏松的研究进展

骨质疏松症被定义为一种系统性骨骼疾病,其特征是骨量低、骨组织微结构恶化、骨脆性和骨折易感性增加。 目前有2亿多人患有骨质疏松症,但由于人口老龄化和人均寿命延长,受影响的人数仍在急剧增加,这是一个重大的公共卫生问题。目前,治疗骨质疏松症的药物开发已经取得了重大进展,但药物治疗并不能逆转骨丢失,且会给患者带来一系列毒副作用。大量研究表明,骨髓间充质干细胞的归巢作用、成骨分化和细胞因子作用在骨质疏松发病过程中发挥重要作用。 移植骨髓间充质干细胞作为一种新方法,不仅能避开药物治疗的副作用而且能从根本上治疗骨质疏松,具有巨大的潜能和应用价值,但许多问题也有待解决。     

催产素体外诱导大鼠骨髓间充质干细胞分化为心肌样细胞

目的 应用催产素(OT)体外诱导骨髓间充质干细胞(BMSCs)向心肌样细胞分化,探索BMSCs向心肌细胞分化的诱导方法.方法 取SD大鼠四肢骨骨髓,分离培养BMSCs,应用OT定向诱导,相差显微镜观察细胞形态学变化,应用免疫细胞化学、激光扫描共焦显微镜技术检测结蛋白、α-横纹肌肌动蛋白、心肌特异性肌钙蛋白T(C-TnT...     

姜黄素调控大鼠骨髓间充质干细胞的成骨分化

背景：姜黄素能明显降低破骨细胞的骨重吸收,诱导破骨细胞凋亡,抑制破骨细胞形成。 目的：观察不同浓度姜黄素对大鼠骨髓间充质干细胞成骨分化的影响。 方法：采用贴壁法分离培养大鼠骨髓间充质干细胞,传至第3代后采用成骨培养基进行成骨诱导,在诱导前3 d于诱导培养基中分别加入0(对照),10,15 μmol/L姜黄素。 结果与结论：接种培养7 d,倒置显微镜下可见分散的骨髓间充质干细胞小集落,集落细胞呈放射状生长。随培养时间延长,细胞集落增大,细胞形态为长梭形。加入成骨培养基7 d后细胞形态逐渐由长梭形变为多角形,随成骨诱导时间延长形态变化更加明显。加入不同浓度姜黄素后骨髓间充质干细胞增殖无变化。姜黄素呈剂量依赖性促进骨髓间充质干细胞碱性磷酸酶活性及Runx-2、血红素单加氧酶1的表达。提示姜黄素能有效促进大鼠骨髓间充质干细胞早期成骨分化,其机制可能与提高干细胞血红素单加氧酶1的表达有关。     

Involvement of receptor-interacting protein 140 in estrogen-mediated osteoclasts differentiation,apoptosis, and bone resorption

Estrogen withdrawal following menopause results in an increase of osteoclasts formation and bone resorption, which is one of the most important mechanisms of postmenopausal osteoporosis. Recently, growing evidence has suggested that receptor-interacting protein 140 was implicated in estrogen-regulated metabolic disease, including fat metabolism and lipid metabolism. However, little is known regarding the role of receptor-interacting protein 140 in the regulation of bone metabolic by estrogen. In the present study, Western blotting disclosed that estrogen brings a significant increasing expression of receptor-interacting protein 140 in osteoclasts, but not in osteoblasts and bone marrow mesenchymal stem cells. Furthermore, analysis of TRAP staining and bone resorption assay showed that depletion of receptor-interacting protein 140 could significantly alleviate the inhibitory effects of estrogen on osteoclasts formation and bone resorption activity. Moreover, estrogen could induce osteoclasts apoptosis by increasing receptor-interacting protein 140 expression through the Fas/FasL pathway. Taken together, receptor-interacting protein 140 might be a critical player in estrogen-mediated osteoclastogenesis and bone resorption.     

Triterpenoids from Cimicifugae rhizoma, a novel class of inhibitors on bone resorption and ovariectomy-induced bone loss

OBJECTIVE: Increasing research suggested that Cimicifugae rhizoma might be protective against osteoporosis. In this study, we investigated the effects of three cycloartane-type triterpenoids isolated from Cimicifugae rhizoma, cimicidol-3-O-beta-D-xyloside (1), cimicidanol-3-O-beta-D-xyloside (2) and acetylacteol-3-O-beta-d-xyloside (3) on bone resorption in vitro and bone loss in ovariectomized (OVX) mice. METHODS: The activities of the tested compounds on bone resorption were evaluated using three assays, neonatal mouse parietal bone organ culture, osteoclast-like cells (OCLs) formation and pit formation. The effects on bone mineral density (BMD) and uterine weight were examined using OVX mice. Using LC-MS/MS method, the serum concentrations of the triterpenoids were measured in mice serum collected at 0.5, 1, 3, 6 and 12h following its oral administration. RESULTS: All of the tested compounds exerted the inhibitory effects on bone resorption in bone organ culture, suppressed both of the formation and the resorbing activity of OCLs. Furthermore, a synergistic effect was observed among those compounds. In vivo studies revealed that compounds 1-3 and the mixture of compounds 1-3 prevented the bone loss in OVX mice without affecting uterine weight, and each compound was detected in the mice serum after single oral administration. CONCLUSIONS: The triterpenoids exerted the inhibitory effects on osteoclastic bone resorption through the suppression of both OCLs formation and the resorbing activity of OCLs, and also showed a significant protective effect on BMD in OVX mice. The present results might provide a new pharmacological potential for the treatment of osteoporosis.     

骨髓间充质干细胞在小鼠早衰性骨质疏松中的细胞生物学功能研究

 目的：研究在小鼠早衰性骨质疏松症中骨髓间充质干细胞（BMMSCs）功能的变化,为揭示骨质疏松发病机制提供理论依据。方法：以早衰小鼠（SAMP6）为动物模型（对照小鼠：SAMR1）,分离培养3个月与6个月小鼠的BMMSCs,利用流式细胞术进行干细胞表型鉴定后用于基因芯片检测筛选差异表达基因,并对该结果进行了Pathway分析。分离培养鉴定2组的BMMSCs并对其成骨与成脂的分化能力进行比较,在诱导分化后进行实时定量RT-PCR检测相关基因的表达,揭示骨髓间充干细胞功能在早衰性骨质疏松中的改变。结果：本研究证明了随着年龄的增长,骨髓间充质干细胞成骨能力降低而成脂能力增高;芯片结果的Pathway分析显示,转化生长因子β（TGF-β）信号通路有4个关键基因发生改变,提示TGF-β信号通路可能在此过程中发挥重要作用。结论：随着年龄增长,早衰性骨质疏松个体的骨髓间充质干细胞生物学功能及TGF-β通路发生了改变,为通过改变骨髓间充质干细胞的生物学功能从而有效逆转治疗、改善骨质疏松状态提供靶点和理论依据。