OBJECTIVE: To investigate the effects of continuous pumping of teriparatide (TPTD) on bone metabolism in ovariectomized and normal mice and provide experimental evidence for the selection of animal models for studying the effects of TPTD and its related peptides on osteoclasts. METHODS: Twenty-four female C57BL mice (6-weeks old) were subjected to ovariectomy (OVX) or sham operation followed 7 days later by continuous pumping of TPTD or the solvent vehicle (VEH) a micropump (SHAM-VEH, SHAM-TPTD, OVX-VEH, and OVX-TPTD groups; =6). Two weeks later, the tibial and femoral bones were harvested for micro-CT scanning to measure the parameters of the tibia and the femoral cortical bone. Histopathological examinations of the tibial tissue were conducted using HE staining and TRAP staining and the number of osteoclasts and the growth plate thickness were determined. The serum Ca2 + levels of the mice were measured. The primary osteoblasts from the cranial bone were treated with estradiol (E2) and TPTD for 48 h, and the expressions of β-catenin and RANKL protein in the cells were analyzed. RESULTS: The trabecular bone mass of OVX mice was significantly lower than that of sham-operated mice ( < 0.05). Continuous TPTD pumping significantly reduced tibial cancellous bone mass and femoral cortical bone area in the sham-operated mice, while in the castrated mice, TPTD pumping increased the cancellous bone mass without changing the cortical bone area. TRAP staining showed that cancellous osteoblasts in the tibia increased significantly in the castrated mice as compared with the sham-operated mice, and TPTD pumping significantly increased the number of cancellous osteoblasts in the sham-operated mice ( < 0.05). In the primary cultured osteoblasts, treatment with both E2 and TPTD obviously lowered the expression of β-catenin and increased the expression of RANKL as compared with TPTD treatment alone. CONCLUSIONS Continuous pumping of TPTD promotes bone resorption in normal mice but does not produce obvious bone resorption effect in the ovariectomized mice, suggesting that castrated mice are not suitable models for studying the effect of TPTD and the related peptides on the osteoclasts.
Animals ; Bone Density ; Bone Density Conservation Agents ; administration & dosage ; pharmacology ; Bone Resorption ; drug therapy ; Bone and Bones ; drug effects ; metabolism ; Female ; Growth Plate ; drug effects ; Mice ; Mice, Inbred C57BL ; Osteoclasts ; drug effects ; Ovariectomy ; RANK Ligand ; metabolism ; Teriparatide ; administration & dosage ; pharmacology ; beta Catenin ; metabolism

OBJECTIVETo further investigate the {ptin vitro} effects of an osteoprotective herbal formula "ELP" (Herba Epimedii, Fructus Ligustri Lucidi and Fructus Psoraleae) using seropharmacological approach.

METHODSRats were fed with ELP or its individual component herbs for 2 days. The serum containing the postabsorbed ingredients of the herbal items were collected for cell culture using UMR106 cell, RAW264.7 cell and mesenchymal stem cell (MSC) isolated from the bone marrow of the rats. The effects of the herbal-containing serum on cell toxicity were detected by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay; bromodeoxyuridine assay was conducted to measure the cell proliferation of UMR106 cell and MSC; cell activity was measured using colorimetric method, and mRNA expression of runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and osteopontin (OPN) of UMR106 and MSC as well as matrix metalloproteinase 9 (MMP-9), tartrate-resistant acid phosphatase (TRAP) and cathepsin K of RAW264.7 were analyzed using real-time reverse-transcription polymerase chain reaction.

RESULTSELP and its component serum exhibited no cytotoxic effects on the cells. The ELP-containing serum increased the proliferation of UMR106 cell and MSC by 25.7% and 14.4 %, respectively and the alkaline phosphatase activity of MSC was increased by 42.6%. On the contrary, it inhibited the RAW264.7 cell differentiation by 29.2 %. ELP serum upregulated the Runx2 expression of UMR and MSC by 1.18 fold and 1.27 fold, respectively. It also upregulated ALP and OPN expression in MSC by 1.69- and 2.12-fold, respectively. On the other hand, ELP serum down-regulated MMP-9 and cathepsin K expression of RAW264.7 cell by 0.46- and 0.36-fold, respectively.

CONCLUSIONSThe serum of the animals fed with ELP contains active ingredients which are effective in promoting osteogenesis and inhibiting osteoclastogenesis.

Absorption, Physiological ; drug effects ; Animals ; Bone and Bones ; drug effects ; pathology ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Male ; Mice ; Osteoclasts ; drug effects ; metabolism ; pathology ; Osteogenesis ; drug effects ; Protective Agents ; pharmacology ; RAW 264.7 Cells ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Serum ; metabolism

OBJECTIVETo examine the effects of brucine on the invasion, migration and bone resorption of receptor activator of nuclear factor-kappa B ligand (RANKL)-induced osteoclastogenesis.

METHODSThe osteoclastogenesis model was builded by co-culturing human breast tumor MDA-MB-231 and mouse RAW264.7 macrophages cells. RANKL (50 ng/mL) and macrophage-colony stimulating factor (50 ng/mL) were added to this system, followed by treatment with brucine (0.02, 0.04 and 0.08 mmol/L), or 10 μmol/L zoledronic acid as positive control. The migration and bone resorption were measured by transwell assay and in vitro bone resorption assay. The protein expressions of Jagged1 and Notch1 were investigated by Western blot. The expressions of transforming growth factor-β1 (TGF-β1), nuclear factor-kappa B (NF-κB) and Hes1 were determined by enzyme-linked immunosorbent assay.

RESULTSCompared with the model group, brucine led to a dose-dependent decrease on migration of MDA-MB-231 cells, inhibited RANKL-induced osteoclastogenesis and bone resorption of RAW264.7 cells (P<0.01). Furthermore, brucine decreased the protein levels of Jagged1 and Notch1 in MDA-MB-231 cells and RAW264.7 cells co-cultured system as well as the expressions of TGF-β1, NF-κB and Hes1 (P<0.05 or P<0.01).

CONCLUSIONBrucine may inhibit osteoclastogenesis by suppressing Jagged1/Notch1 signaling pathways.

Animals ; Bone Neoplasms ; metabolism ; prevention & control ; secondary ; Breast Neoplasms ; drug therapy ; metabolism ; pathology ; Cell Differentiation ; drug effects ; Cells, Cultured ; Female ; Humans ; Jagged-1 Protein ; metabolism ; Macrophages ; drug effects ; physiology ; Mice ; Osteoclasts ; drug effects ; physiology ; Receptor, Notch1 ; metabolism ; Signal Transduction ; drug effects ; Strychnine ; analogs & derivatives ; pharmacology ; therapeutic use

The present study aimed at investigating the effects of Puerarin (PR), a major isoflavonoid isolated from the Chinese medicinal herb Puerariae radix, on bone metabolism and the underlying mechanism of action. The in vivo assay, female mice were ovariectomized (OVX), and the OVX mice were fed with a diet containing low, middle, and high doses of PR (2, 4, and 8 mg·d(-1), respectively) or 17β-estradiol (E2, 0.03 μg·d(-1)) for 4 weeks. In OVX mice, the uterine weight declined, and intake of PR at any dose did not affect uterine weight, compared with the control. The total femoral bone mineral density (BMD) was significantly reduced by OVX, which was reversed by intake of the diet with PR at any dose, especially at the low dose. In the in vitro assay, RAW264.7 cells were used for studying the direct effect of PR on the formation of osteoclasts. PR reduced the formation of tartrate resistant acid phosphatase (TRAP)-positive multi-nucleated cells in the RAW 264.7 cells induced by receptor activator for nuclear factor-κB Ligand (RANKL). MC3T3-E1 cells were used for studying the effects of PR on the expression of osteoprotegerin (OPG) and RANKL mRNA expression in osteoblasts. The expression of OPG mRNA and RANKL mRNA was detected by RT-PCR on Days of 5, 7, 10, and 12 after PR exposure. PR time-dependently enhanced the expression of OPG mRNA and reduced the expression of RANKL mRNA in MC3T3-E1 cells. In conclusion, our results suggest that PR can effectively prevent bone loss in OVX mice without any hyperplastic effect on the uterus, and the antiosteoporosis activity of PR may be related to its effects on the formation of osteoclasts and the expression of RANKL OPG in osteoblasts.
Animals ; Bone Density ; drug effects ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Femur ; chemistry ; growth & development ; metabolism ; Humans ; Isoflavones ; administration & dosage ; Mice ; Osteoclasts ; drug effects ; metabolism ; Osteoporosis ; genetics ; metabolism ; physiopathology ; prevention & control ; Osteoprotegerin ; genetics ; metabolism ; Ovariectomy ; Pueraria ; chemistry ; RANK Ligand ; genetics ; metabolism

BACKGROUND/AIMS: Proton pump inhibitors (PPIs) act by irreversibly binding to the H+-K+-ATPase of the proton pump in parietal cells and may possibly affect the vacuolar H+-ATPase in osteoclasts. METHODS: We investigated the effect of 8 weeks of PPI treatment on the parameters of bone turnover and compared PPI with revaprazan, which acts by reversibly binding to H+-K+-ATPase in proton pumps. This study was a parallel randomized controlled trial. For 8 weeks, either a PPI or revaprazan was randomly assigned to patients with gastric ulcers. The parameters of bone turnover were measured at the beginning of and after the 8-week treatment period. RESULTS: Twenty-six patients (PPI, n=13; revaprazan, n=13) completed the intention-to-treat analysis. After the 8-week treatment period, serum calcium and urine deoxypyridinoline (DPD) were increased in the PPI group (serum calcium, p=0.046; urine DPD, p=0.046) but not in the revaprazan group. According to multivariate linear regression analysis, age > or =60 years was an independent predictor for the changes in serum calcium and urine DPD. CONCLUSIONS: In elderly patients, administering a PPI for 8 weeks altered bone parameters. Our study suggested that PPIs might directly alter bone metabolism via the vacuolar H+-ATPase in osteoclasts.
Aged ; Amino Acids/drug effects/urine ; Bone Remodeling/*drug effects ; Bone and Bones/*metabolism ; Calcium/blood ; Female ; Humans ; Intention to Treat Analysis ; Linear Models ; Male ; Middle Aged ; Multivariate Analysis ; Osteoclasts/*metabolism ; Prospective Studies ; Proton Pump Inhibitors/*pharmacology ; Pyrimidinones/*pharmacology ; Tetrahydroisoquinolines/*pharmacology

OBJECTIVETo discuss the effect of Drynariae Rhizoma's naringin on osteoclasts induced by mouse monocyte RAW264.7.

METHODRAW264.7 cells were induced by 100 μg x L(-1) nuclear factor-κB receptor activator ligand (RANKL) and became mature osteoclasts, which were identified through TRAP specific staining and bone resorption. MTT method was sued to screen and inhibit and the highest concentration of osteoclasts. After being cultured with the screened medium containing naringin for 5 days, positive TRAP cell counting and bone absorption area analysis were adopted to observe the effect of naringin on the formation of osteoclast sells and the bone absorption function. The osteoclast proliferation was measured by flow cytometry. The effects of RANK, TRAP, MMP-9, NFATc1 and C-fos mRNA expressions on nuclear factor-κB were detected by RT-PCR.

RESULTNaringin could inhibit osteoclast differentiation, bone absorption function and proliferation activity of osteoclasts, significantly down-regulate RANK, TRAP, MMP-9 and NFATc1 mRNA expressions in the osteoclast differentiation process, and up-regulate the C-fos mRNA expression.

CONCLUSIONNaringin could inhibit osteoclast differentiation, proliferation and bone absorption function. Its mechanism may be achieved by inhibiting the specific gene expression during the osteoclast differentiation process.

Acid Phosphatase ; metabolism ; Animals ; Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Flavanones ; pharmacology ; Isoenzymes ; metabolism ; Matrix Metalloproteinase 9 ; genetics ; Mice ; NFATC Transcription Factors ; genetics ; Osteoclasts ; cytology ; drug effects ; Tartrate-Resistant Acid Phosphatase

Skeletal fluorosis is a chronically metabolic bone disease with extensive hyperostosis osteosclerosis caused by long time exposure to fluoride. Skeletal fluorosis brings about a series of abnormal changes of the extremity, such as joint pain, joint stiffness, bone deformity, etc. Differentiation and maturation of osteoblasts were regulated by osteoclasts via Sema4D/Plexin-B1 signaling pathway. Furthermore, the differentiation and maturation of osteoclasts are conducted by osteoblasts via RANKL/RANK/OPG pathway. Both of these processes form a feedback circuit which is a key link in skeletal fluorosis. In this study, an osteoblast-osteoclast co-culture model in vitro was developed to illustrate the mechanism of skeletal fluorosis. With the increase of fluoride concentration, the expression level of Sema4D was decreased and TGF-β1 was increased continuously. OPG/RANKL mRNA level, however, increased gradually. On the basis of that, the inhibition of Sema4D/Plexin-B1/RhoA/ROCK signaling pathway caused by fluoride promoted the level of TGF-β1 and activated the proliferation of osteoblasts. In addition, osteroprotegerin (OPG) secreted by osteoblasts was up-regulated by fluoride. The competitive combination of OPG and RANKL was strengthened and the combination of RANKL and RANK was hindered. And then the differentiation and maturation of osteoclasts were inhibited, and bone absorption was weakened, leading to skeletal fluorosis.
Animals ; Antigens, CD ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Feedback, Physiological ; Fetus ; Fluorides ; pharmacology ; GTPase-Activating Proteins ; genetics ; metabolism ; Gene Expression Regulation, Developmental ; Osteoblasts ; drug effects ; metabolism ; pathology ; Osteoclasts ; drug effects ; metabolism ; pathology ; Osteogenesis ; drug effects ; genetics ; Osteoprotegerin ; genetics ; metabolism ; RANK Ligand ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Receptor Activator of Nuclear Factor-kappa B ; genetics ; metabolism ; Receptors, Cell Surface ; genetics ; metabolism ; Semaphorins ; genetics ; metabolism ; Signal Transduction ; Transforming Growth Factor beta1 ; genetics ; metabolism ; rho-Associated Kinases ; genetics ; metabolism ; rhoA GTP-Binding Protein ; genetics ; metabolism

Osteoclast-like cells are known to inhibit arterial calcification. Receptor activator of NF-κB ligand (RANKL) is likely to act as an inducer of osteoclast-like cell differentiation. However, several studies have shown that RANKL promotes arterial calcification rather than inhibiting arterial calcification. The present study was conducted in order to investigate and elucidate this paradox. Firstly, RANKL was added into the media, and the monocyte precursor cells were cultured. Morphological observation and Tartrate resistant acid phosphatase (TRAP) staining were used to assess whether RANKL could induce the monocyte precursor cells to differentiate into osteoclast-like cells. During arterial calcification, in vivo and in vitro expression of RANKL and its inhibitor, osteoprotegerin (OPG), was detected by real-time PCR. The extent of osteoclast-like cell differentiation was also assessed. It was found RANKL could induce osteoclast-like cell differentiation. There was no in vivo or in vitro expression of osteoclast-like cells in the early stage of calcification. At that time, the ratio of RANKL to OPG was very low. In the late stage of calcification, a small amount of osteoclast-like cell expression coincided with a relatively high ratio of RANKL to OPG. According to the results, the ratio of RANKL to OPG was very low during most of the arterial calcification period. This made it possible for OPG to completely inhibit RANKL-induced osteoclast-like cell differentiation. This likely explains why RANKL had the ability to induce osteoclast-like cell differentiation but acted as a promoter of calcification instead.
Acid Phosphatase ; genetics ; metabolism ; Animals ; Aorta ; drug effects ; metabolism ; pathology ; Cell Differentiation ; Coculture Techniques ; Gene Expression Regulation ; Isoenzymes ; genetics ; metabolism ; Male ; Monocytes ; cytology ; drug effects ; metabolism ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; pathology ; Osteoclasts ; drug effects ; metabolism ; pathology ; Osteoprotegerin ; genetics ; metabolism ; RANK Ligand ; genetics ; metabolism ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Signal Transduction ; Tartrate-Resistant Acid Phosphatase ; Vascular Calcification ; genetics ; metabolism ; pathology

The purpose of this study was to determine whether the Ca2+ signaling pathway is involved in the ability of osteoprotegerin (OPG) to inhibit osteoclast differentiation and maturation. RAW264.7 cells were incubated with macrophage colony-stimulating factor (M-CSF) + receptor activator of nuclear factor-kappaB ligand (RANKL) to stimulate osteoclastogenesis and then treated with different concentrations of OPG, an inhibitor of osteoclast differentiation. The intracellular Ca2+ concentration [Ca2+]i and phosphorylation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in the different treatment groups were measured by flow cytometry and Western blotting, respectively. The results confirmed that M-CSF + RANKL significantly increased [Ca2+]i and CaMKII phosphorylation in osteoclasts (p < 0.01), and that these effects were subsequently decreased by OPG treatment. Exposure to specific inhibitors of the Ca2+ signaling pathway revealed that these changes varied between the different OPG treatment groups. Findings from the present study indicated that the Ca2+ signaling pathway is involved in both the regulation of osteoclastogenesis as well as inhibition of osteoclast differentiation and activation by OPG.
Animals ; Calcium/*metabolism ; *Calcium Signaling ; *Cell Differentiation/drug effects ; Cell Line ; Cell Survival/drug effects ; Gene Expression Regulation/drug effects ; Macrophage Colony-Stimulating Factor/metabolism ; Mice ; Osteoclasts/*cytology/*drug effects/*metabolism ; Osteoprotegerin/*pharmacology ; RANK Ligand/metabolism

Eupatilin is the main active component of DA-9601, an extract from Artemisia. Recently, eupatilin was reported to have anti-inflammatory properties. We investigated the anti-arthritic effect of eupatilin in a murine arthritis model and human rheumatoid synoviocytes. DA-9601 was injected into collagen-induced arthritis (CIA) mice. Arthritis score was regularly evaluated. Mouse monocytes were differentiated into osteoclasts when eupatilin was added simultaneously. Osteoclasts were stained with tartrate-resistant acid phosphatase and then manually counted. Rheumatoid synoviocytes were stimulated with TNF-alpha and then treated with eupatilin, and the levels of IL-6 and IL-1beta mRNA expression in synoviocytes were measured by RT-PCR. Intraperitoneal injection of DA-9601 reduced arthritis scores in CIA mice. TNF-alpha treatment of synoviocytes increased the expression of IL-6 and IL-1beta mRNAs, which was inhibited by eupatilin. Eupatilin decreased the number of osteoclasts in a concentration dependent manner. These findings, showing that eupatilin and DA-9601 inhibited the expression of inflammatory cytokines and the differentiation of osteoclasts, suggest that eupatilin and DA-9601 is a candidate anti-inflammatory agent.
Animals ; Anti-Inflammatory Agents/pharmacology/*therapeutic use ; Arthritis, Experimental/chemically induced/*drug therapy ; Arthritis, Rheumatoid/drug therapy/pathology ; Cell Differentiation/*drug effects ; Cells, Cultured ; Collagen Type II ; Cytokines/biosynthesis ; Disease Models, Animal ; Drugs, Chinese Herbal/therapeutic use ; Female ; Flavonoids/pharmacology/*therapeutic use ; Humans ; Inflammation/drug therapy/immunology ; Interleukin-1beta/genetics/metabolism ; Interleukin-6/genetics/metabolism ; Lymph Nodes/cytology ; Mice ; Mice, Inbred DBA ; Monocytes/cytology ; Osteoclasts/*cytology ; Plant Extracts/pharmacology ; RNA, Messenger/biosynthesis ; Synovial Membrane/cytology ; T-Lymphocytes, Regulatory/cytology/immunology ; Tumor Necrosis Factor-alpha/pharmacology