Objective: To evaluate the application of mechanically reinforced 45S5 Bioglass^®-derived glass ceramic porous scaffolds for repair of bone defect in rabbits. Methods: The BG-ZnB powders were added into the 45S5 Bioglass^® powder/paraffin microsphere mixtures and were sintered at 900℃ to obtain porous scaffolds with highly bioactive BG-ZnB of 0%, 2% or 4% of mass fraction (denoted as 45S5/ZnB0, 45S5/ZnB2, 45S5/ZnB4). Phase composition, porosity and compression properties of three kinds of as-sintered scaffolds were characterized by X-ray analysis, mercury porosimetry, and mechanical test. Thirty-six male New Zealand rabbits with critical-sized femoral bone defects were randomly divided into three groups (45S5/ZnB0 group, 45S5/ZnB2 group and 45S5/ZnB4 group, 12 for each), and were implanted with three kinds of porous scaffolds respectively. X-ray, micro-CT three-dimensional reconstruction and tissue slice staining were used to detected the efficiency of bone regeneration at 6 and 16 weeks after operation. The growth of newly formed bone was observed using HE, Masson staining and EnVision method. Results: Phase compositions of 45S5/ZnB2 and 45S5/ZnB4 were the same with 45S5/ZnB0, but the average pore size and porosity of the scaffolds were decreased with the increase of BG-ZnB content. 45S5/ZnB2 and 45S5/ZnB4 scaffolds exhibited higher compressive strength, osteogenesis and trabecular density than those of the 45S5/ZnB0 scaffold (all P<0.05). With the mechanical reinforcement of BG-ZnB increased, the content of new bone, collagen type I and osteocalcin increased. Conclusion: Low-melt BG-ZnB-assisted sintering is a promising approach to improve the mechanical strength of 45S5 Bioglass^®.
Animals ; Bone and Bones ; drug effects ; physiology ; Ceramics ; chemistry ; Glass ; Male ; Porosity ; Rabbits ; Tissue Scaffolds ; chemistry

Flavonoid naringin is widely distributed in various types of plants and is an important component of herbal Drynaria. In previous studies, Drynaria has been demonstrated to have inhibitory effects on inflammatory responses and bone destruction and exert anabolic effects on bone, has been widely used in the clinical treatment. Naringin, was in the stage of experimental yet. The experimental results have confirmed that naringin suppressed inflammation including arthritis by lowering the expression of inflammatory cytokines, and the mechanism can be explained as reducing the expression of NF-κB. Naringin has been shown to increase osteoblast proliferation by increasing the expression of BMP-2, inhibit osteoclast activity by reducing the expression of RANKL. In animal experimental, naringin was useful for osteoporosis, and the mechanisms are in-depth studies. Research in the field of traditional Chinese medicine and orthopedics, naringin as a explicit material structure in the components of Drynaria, has been concerned about the experimental studies, it is not only prosperity the development of traditional Chinese medicine research,but also ready for clinical studies anti-inflammatory and bone effects of naringin in the future.
Animals ; Anti-Inflammatory Agents ; pharmacology ; Bone and Bones ; drug effects ; Flavanones ; pharmacology ; Humans ; Medicine, Chinese Traditional ; Osteoblasts ; drug effects ; Osteoclasts ; drug effects ; Osteoporosis ; drug therapy ; Polypodiaceae ; chemistry

We investigated the development of an injectable, biodegradable hydrogel composite of poly(trimethylene carbonate)-F127-poly(trimethylene carbonate)(PTMC11-F127-PTMC11 )loaded with bone morphogenetic protein-2 (BMP-2) derived peptide P24 for ectopic bone formation in vivo and evaluated its release kinetics in vitro. Then we evaluated P24 peptide release kinetics from different concentration of PTMC11-F127-PTMC11 hydrogel in vitro using bicinchoninic acid (BCA)assay. P24/ PTMC11-F127-PTMC11 hydrogel was implanted into each rat's erector muscle of spine and ectopic bone formation of the implanted gel in vivo was detected by hematoxylin and eosin stain (HE). PTMC11-F127-PTMC11 hydrogel with concentration more than 20 percent showed sustained slow release for one month after the initial burst release. Bone trabeculae surround the P24/ PTMC11-F127-PTMC11 hydrogel was shown at the end of six weeks by hematoxylin and eosin stain. These results indicated that encapsulated bone morphogenetic protein (BMP-2) derived peptide P24 remained viable in vivo, thus suggesting the potential of PTMC11-F127-PT- MC11 composite hydrogels as part of a novel strategy for localized delivery of bioactive molecules.
Animals ; Biocompatible Materials ; chemistry ; Bone Morphogenetic Proteins ; pharmacology ; Bone and Bones ; drug effects ; Dioxanes ; chemistry ; Drug Delivery Systems ; Hydrogels ; chemistry ; Osteogenesis ; drug effects ; Peptides ; Prostheses and Implants ; Rats

OBJECTIVETo observe the function of wnt/β-catenin signal pathway on the process that epimedium-derived flavonoids (EFs) regulate the balance between osteogenic differentiation and adipogenic differentiation in bone marrow stromal cells of ovariectomized rats, and to provide an experimental evidence for the mechanism of EFs on treating postmenopausal osteoporosis.

METHODSBone marrow stromal cells from ovariectomized rats were separated and cultivated in the condition of osteoinductive medium or liquid medium for 15 days. Low- (1 μg/mL), medium- (10 μg/mL) and high- (100 μg/mL) dose EFs were administrated correspondingly. Alkaline phosphatase (ALP) staining, ALP activity determination, oil red O staining and realtime polymerese chain reaction (RT-PCR) were used to determine the effect of EFs on osteogenic differentiation and adipogenic differentiation in bone marrow stromal cells of ovariectomized rats. Moreover, in order to explore the mechanism of EFs on osteogenic differentiation and adipogenic differentiation in bone marrow stromal cells of ovariectomized rats, Dickkopf-related protein 1 (DKK1) was used in the medium group. Enzymelinked immunosorbent assay (ELISA) and RT-PCR were used to determine mRNA levels of β-catenin, low density lipoprotein receptor-related protein 5 (LRP5) and T cell factor (TCF) protein, known as wnt/β-catenin signal pathway related factors.

RESULTSEFs increased mRNA expression levels of ALP and early osteoblast differentiation factors, such as runt-related transcription factor 2 (Runx2), osteocalcin and collagen I, and decreased mRNA expression levels of fat generation factors, such as peroxisome proliferator activated receptor gamma 2 (PPARγ-2) and CCAAT enhancer-binding protein-α (C/EBPα) in a dose-dependent manner. While osteoblast differentiation factors were down-regulated, fat generation factors were up-regulated when DKK1 was applied. Also EFs up-regulated mRNA expression levels of β-catenin, LRP5 and TCF protein which could be blocked by DKK1.

CONCLUSIONEFs regulate the balance between osteogenic differentiation and adipogenic differentiation in bone marrow stromal cells of ovariectomized rats by activating wnt/β-catenin signal pathway, which may be an important molecular mechanism of EFs on treating postmenopausal osteoporosis.

Adipose Tissue ; cytology ; drug effects ; metabolism ; Animals ; Base Sequence ; Bone and Bones ; cytology ; drug effects ; metabolism ; Cell Differentiation ; drug effects ; DNA Primers ; Enzyme-Linked Immunosorbent Assay ; Epimedium ; chemistry ; Female ; Flavonoids ; pharmacology ; Flow Cytometry ; Mesenchymal Stromal Cells ; cytology ; drug effects ; metabolism ; Rats ; Real-Time Polymerase Chain Reaction ; Signal Transduction ; Wnt Proteins ; metabolism ; beta Catenin ; metabolism

The aim of this study is to investigate a new method for preparing a biomimetic bone material-surface modified sintered bovine cancellous bone, and to improve its bioactivity as a tissue engineering bone. The prepared sintered bovine cancellous bones with the same size were randomly divided into two groups, immersing in 1 and 1. 5 times simulated body fluid (SBF), respectively. The three time periods of soak time were 7, 14, and 21 days. After sintered bone was dried, the surface morphology of sintered bone and surface mineralization composition were observed under scanning electron microscopy (SEM). By comparing the effect of surface modification of sintered bone materials, we chose the most ideal material and studied its pore size, the rate of the porosity, the compress and bend intensity. And then the material and the sintered bone material without surface modification were compared. The study indicated that sintered bone material immersed in SBF (1.5 times) for 14 days showed the best effect of surface modification, retaining the original physico-chemical properties of sintered bone.
Animals ; Biocompatible Materials ; chemical synthesis ; Biomimetic Materials ; chemical synthesis ; Bone Substitutes ; Bone and Bones ; chemistry ; drug effects ; Calcification, Physiologic ; physiology ; Cattle ; Chemical Phenomena ; Hydroxyapatites ; chemistry ; Porosity ; Surface Properties ; Tissue Engineering ; methods

BACKGROUND: Estrogens act on estrogen receptors distributed in articular cartilages, synovial membrane, and ligaments, which are thought to be related with degenerative changes. Meanwhile, progesterone is known to have a weak anabolic action on bone formation This study evaluates the effects of estrogen and progesterone hormone on bone/cartilage turnover in ovariectomized (OVX) rats. METHODS: Thirty-five 7-month-old female Sprague-Dawley rats were randomly divided into 5 groups and then ovariectomized bilaterally except the sham control group. The first and the second group acting as controls did not receive hormonal therapy, the third group received estrogen, the fourth group received progesterone, and the fifth group received combination of both hormones 10 weeks after surgery. Evaluations were done using the serum levels of cartilage oligomeric matrix protein (COMP) for cartilage turnover, collagen type I C-telopeptide (CTX-1) and osteocalcin (OC) for bone turnover at 11, 15, 19 weeks after OVX and histology using the Osteoarthritis Research Society International (OARSI) osteoarthritis (OA) cartilage histopathology assessment system. RESULTS: Significantly less cartilage degradation (decreased levels of COMP) was found in the combined hormone treated group in comparison with OVX group. Similarly, both hormonal treatment resulted in increased bone formation and decreased bone resorption i.e., a low overall bone turnover status (decrease in the serum OC and CTX-1 levels). CONCLUSIONS: Combined estrogen and progesterone therapy was found to be convincing in terms of reducing the severity of OA in this experimental model.
Animals ; Biological Markers/blood/metabolism ; Bone Remodeling/*drug effects ; Bone and Bones/chemistry/drug effects ; Cartilage/chemistry/*drug effects ; Collagen Type I/blood/metabolism ; Disease Models, Animal ; Estrogens/*pharmacology ; Extracellular Matrix Proteins/blood/metabolism ; Female ; Glycoproteins/blood/metabolism ; Histocytochemistry ; Hormone Replacement Therapy/*methods ; Osteoarthritis/blood/*drug therapy ; Osteocalcin/blood/metabolism ; Ovariectomy ; Progesterone/*pharmacology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study the effect of growth hormone (GH) combined with Radix Dipsaci on the body growth and the bone mineral content (BMC) of hypophysectomized rats.

METHODSThe GH deficiency rats model was established using the hypophysectomized operation through the skull and the throat. Qualified rats were divided into the sham-operation group (n = 15), the negative control group (n = 13), the GH intervention group (n = 13), and the GH combined with Radix Dipsaci group(n = 12). GH (0.25 mg/kg) was subcutaneously injected from the cervical part in the GH intervention group and the GH combined with Radix Dipsaci group at the same time, while equal volume of normal saline was injected to the rest groups. 0.7 mL/100 kg Radix Dipsaci was given by gastrogavage to the GH combined with Radix Dipsaci group at the same time, while equal volume of normal saline was given by gastrogave to the rest groups. The body weight, the tail length, and the body length were measured during the intervention period. Blood was withdrawn after 14-day intervention. The femoral bone and the tibial bone were taken out. The levels of GH, insulin-like growth factor 1 (IGF-1), alkaline phosphatase (ALP), and osteocalcin (OC) were measured. The width of the tibial epiphyseal plate was measured. The bilateral femur bone mineral density (BMD) and BMC were measured using the dual energy X-ray absorptiometry.

RESULTSThe body weight, the body length, the length of the femoral bone, the length of the tibial bone, the width of the epiphyseal plate, the levels of the GH, IGF-1, ALP, and OC increased in the GH intervention group and the GH combined with Radix Dipsaci group after 2-week intervention, showing statistical difference when compared with the model group (P < 0.01). But there was no statistical difference in the tail length though it also increased (P > 0.05). There was insignificant difference in the aforesaid indices between the two groups (P > 0.05). Compared with the model group, the BMD of the GH combined with Radix Dipsaci group increased with statistical difference (P < 0.01). Compared with the model group, the BMC of the GH intervention group and the GH combined with Radix Dipsaci group increased with statistical difference (P < 0.01). It was highest in the GH combined with Radix Dipsaci group (P < 0.01).

CONCLUSIONSGH combined with Radix Dipsaci showed unobvious effect on promoting the growth. But it could elevate BMD and BMC, and improve the bone metabolism.

Animals ; Bone Development ; drug effects ; Bone and Bones ; metabolism ; Dipsacaceae ; chemistry ; Drugs, Chinese Herbal ; pharmacology ; Growth Hormone ; pharmacology ; Hypophysectomy ; Male ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the effect of Panax Notoginseng Saponins (PNS) on tendon healing in bone tunnel.

METHODSThe experiment was performed in the animal laboratory, Wangjing hospital from April to August, 2010. All the experiment procedures were accorded with the animal ethical requirements. Twenty New Zealand rabbits were randomly divided into blank control group and PNS group with 10 animals in each group. Anterior cruciate ligament reconstruction with toe extensor tendon was done in knee joints of rabbits by suspend fixation model. PNS was injected in bone tunnel of rabbits in PNS group, and nothing was given to blank group. Specimens were collected at 4 and 8 weeks after surgery. Sections were stained with HE stain to observe the changes of interface tissue between bone tunnel and tendon graft. Interface types were classified according to Yamakado method.

RESULTSAt 4 weeks after surgery, the interface was filled with connective tissue in both group, while at 8 weeks, there was not obvious gap between bone and tendon graft in both groups under macrography. Under microscope, there were more fibroblast in the PNS group. There was larger new bone formation area in PNS group. The classification on the Yamakado type was significantly different between two group (P < 0.05).

CONCLUSIONPNS can enhance tendon-bone healing in bone tunnel, and promote the connection between tendon and bone. The study lacks quantitative analysis of those criteria, and the mechanics of the promotion of tendon-bone healing has not been totally clear.

Animals ; Bone and Bones ; drug effects ; pathology ; physiopathology ; Cell Count ; Cell Proliferation ; drug effects ; Cell Shape ; drug effects ; Fibroblasts ; drug effects ; pathology ; Male ; Neovascularization, Physiologic ; drug effects ; Panax notoginseng ; chemistry ; Rabbits ; Saponins ; pharmacology ; Tendons ; drug effects ; pathology ; physiopathology ; transplantation ; Transplantation, Autologous ; Wound Healing ; drug effects

Mussel adhesive proteins have attracted increasing interests for their potential use as environmentally friendly bioadhesives in medicine and aqueous conditions. In this study, surface coating analysis, quartz crystal microbalance (QCM), cell and bone tissue adhesion and cytotoxicity assay were used to study the properties of the Perna viridis foot proteins (Pvfp) extract as bioadhesive. The results of coating ability on various materials and QCM analysis revealed that Pvfp extract has comparable or superior adsorbtion ability to that of Cell-Tak (the naturally extracted MAP mixture from Mytilus edulis, and has been commercialized), and also, the cell adhesion ability of Pvfp extract was stronger than that of Cell-Tak and poly-L-lysine. No cytotoxicity was detected using human HeLa and 293T cells. Furthermore, broken bones of mouse could be stuck together by use of Pvfp extract. In bulk-scale adhesion tests, Pvfp extract showed much greater tensile strength than did fibrin glue for conglutinating poly (vinl chloride) sticks and for binding together pig's femur segments. These results suggested that Pvfp extract be an efficient cell and tissue adhesive in biotechnological application and it might be a potential bioadhesive in medical practice.
Animals ; Bone Cements ; isolation & purification ; Bone and Bones ; drug effects ; HeLa Cells ; Humans ; Mice ; Perna ; chemistry ; Proteins ; isolation & purification ; pharmacology ; Swine ; Tissue Adhesives ; isolation & purification

The RGD-containing peptide was used to modify the surface of porous PLGA-[ASP-PEG], and was incubated in the modified simulated body fluid (mSBF) for two weeks. The mineralization of PLGA-[ASP-PEG] was explored. The active peptide was used to modify PLGA-[ASP-PEG] through cross-linker (Sulfo-LC-SPDP), characterized by X-ray photoelectron spectroscopy (XPS) the peptide-modified PLGA-[ASP-PEG] (Experiment group, EG) and PLGA-[ASP-PEG] without modification (Control group, CG) were all incubated in mSBF for two weeks, confirmed by observation of Scanning electron microscope(SEM) and measurements of Energy dispersive analysis system of X-ray (EDS) and X-ray diffractometry (XRD). XPS indicated that the binding energy of sulphur in EG was 164eV, and the ratio of carbon to sulphur in EG was 99.746 : 0.1014, however, sulphur was not detected in CG; SEM analysis demonstrated that the mineralization layers were more consecutive and compact in EG than in CG. The results of EDS and XRD indicated that the main component of mineral was hydroxyapatite, and the ratio of Ca/P was 1.60 in EG, and 1.52 in CG. RGD-containing peptide provided enough functional groups for mineralization; the mineralized peptide- modified PLGA-[ASP-PEG] possessed the bonelike microstructure.
Biocompatible Materials ; chemistry ; Bone Substitutes ; Bone and Bones ; metabolism ; Calcification, Physiologic ; Lactic Acid ; chemistry ; Oligopeptides ; chemistry ; Osteogenesis ; drug effects ; Peptides ; chemical synthesis ; pharmacology ; Polyglycolic Acid ; chemistry ; Surface Properties