Sample records for increased bone morphogenetic

  1. Tissue engineering skeletal muscle for orthopaedic applications

    NASA Technical Reports Server (NTRS)

    Payumo, Francis C.; Kim, Hyun D.; Sherling, Michael A.; Smith, Lee P.; Powell, Courtney; Wang, Xiao; Keeping, Hugh S.; Valentini, Robert F.; Vandenburgh, Herman H.

    2002-01-01

    With current technology, tissue-engineered skeletal muscle analogues (bioartificial muscles) generate too little active force to be clinically useful in orthopaedic applications. They have been engineered genetically with numerous transgenes (growth hormone, insulinlike growth factor-1, erythropoietin, vascular endothelial growth factor), and have been shown to deliver these therapeutic proteins either locally or systemically for months in vivo. Bone morphogenetic proteins belonging to the transforming growth factor-beta superfamily are osteoinductive molecules that drive the differentiation pathway of mesenchymal cells toward the chondroblastic or osteoblastic lineage, and stimulate bone formation in vivo. To determine whether skeletal muscle cells endogenously expressing bone morphogenetic proteins might serve as a vehicle for systemic bone morphogenetic protein delivery in vivo, proliferating skeletal myoblasts (C2C12) were transduced with a replication defective retrovirus containing the gene for recombinant human bone morphogenetic protein-6 (C2BMP-6). The C2BMP-6 cells constitutively expressed recombinant human bone morphogenetic protein-6 and synthesized bioactive recombinant human bone morphogenetic protein-6, based on increased alkaline phosphatase activity in coincubated mesenchymal cells. C2BMP-6 cells did not secrete soluble, bioactive recombinant human bone morphogenetic protein-6, but retained the bioactivity in the cell layer. Therefore, genetically-engineered skeletal muscle cells might serve as a platform for long-term delivery of osteoinductive bone morphogenetic proteins locally.

  2. Key role of the expression of bone morphogenetic proteins in increasing the osteogenic activity of osteoblast-like cells exposed to shock waves and seeded on bioactive glass-ceramic scaffolds for bone tissue engineering.

    PubMed

    Muzio, Giuliana; Martinasso, Germana; Baino, Francesco; Frairia, Roberto; Vitale-Brovarone, Chiara; Canuto, Rosa A

    2014-11-01

    In this work, the role of shock wave-induced increase of bone morphogenetic proteins in modulating the osteogenic properties of osteoblast-like cells seeded on a bioactive scaffold was investigated using gremlin as a bone morphogenetic protein antagonist. Bone-like glass-ceramic scaffolds, based on a silicate experimental bioactive glass developed at the Politecnico di Torino, were produced by the sponge replication method and used as porous substrates for cell culture. Human MG-63 cells, exposed to shock waves and seeded on the scaffolds, were treated with gremlin every two days and analysed after 20 days for the expression of osteoblast differentiation markers. Shock waves have been shown to induce osteogenic activity mediated by increased expression of alkaline phosphatase, osteocalcin, type I collagen, BMP-4 and BMP-7. Cells exposed to shock waves plus gremlin showed increased growth in comparison with cells treated with shock waves alone and, conversely, mRNA contents of alkaline phosphatase and osteocalcin were significantly lower. Therefore, the shock wave-mediated increased expression of bone morphogenetic protein in MG-63 cells seeded on the scaffolds is essential in improving osteogenic activity; blocking bone morphogenetic protein via gremlin completely prevents the increase of alkaline phosphatase and osteocalcin. The results confirmed that the combination of glass-ceramic scaffolds and shock waves exposure could be used to significantly improve osteogenesis opening new perspectives for bone regenerative medicine. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  3. Connective tissue growth factor and bone morphogenetic protein 2 are induced following myocardial ischemia in mice and humans.

    PubMed

    Rutkovskiy, Arkady; Sagave, Julia; Czibik, Gabor; Baysa, Anton; Zihlavnikova Enayati, Katarina; Hillestad, Vigdis; Dahl, Christen Peder; Fiane, Arnt; Gullestad, Lars; Gravning, Jørgen; Ahmed, Shakil; Attramadal, Håvard; Valen, Guro; Vaage, Jarle

    2017-09-01

    We aimed to study the cardiac expression of bone morphogenetic protein 2, its receptor 1 b, and connective tissue growth factor, factors implicated in cardiac embryogenesis, following ischemia/hypoxia, heart failure, and in remodeling hearts from humans and mice. Biopsies from the left ventricle of patients with end-stage heart failure due to dilated cardiomyopathy or coronary artery disease were compared with donor hearts and biopsies from patients with normal heart function undergoing coronary artery bypass grafting. Mouse model of post-infarction remodeling was made by permanent ligation of the left coronary artery. Hearts were analyzed by real-time polymerase chain reaction and Western blotting after 24 hours and after 2 and 4 weeks. Patients with dilated cardiomyopathy and mice post-infarction had increased cardiac expression of connective tissue growth factor. Bone morphogenetic protein 2 was increased in human hearts failing due to coronary artery disease and in mice post-infarction. Gene expression of bone morphogenetic protein receptor 1 beta was reduced in hearts of patients with failure, but increased two weeks following permanent ligation of the left coronary artery in mice. In conclusion, connective tissue growth factor is upregulated in hearts of humans with dilated cardiomyopathy, bone morphogenetic protein 2 is upregulated in remodeling due to myocardial infarction while its receptor 1 b in human failing hearts is downregulated. A potential explanation might be an attempt to engage regenerative processes, which should be addressed by further, mechanistic studies.

  4. Bone morphogenetic protein-mediated interaction of periosteum and diaphysis. Citric acid and other factors influencing the generation of parosteal bone.

    PubMed

    Kübler, N; Urist, M R

    1990-09-01

    In rabbits, after long-bone growth is complete and the cambium layer regresses, mesenchymal-type cells with embryonic potential (competence) for bone development persist in the adventitial layer of periosteum. These cells are not determined osteoprogenitor cells (stem cells) because bone tissue differentiation does not occur when adult periosteum is transplanted into a heterotopic site. In this respect, adventitial cells differ from bone marrow stroma cells. In a parosteal orthotopic site in the space between the adult periosteum and diaphysis, implants of bone morphogenetic protein (BMP) and associated noncollagenous proteins (BMP/NCP) induce adventitia and adjacent muscle connective-tissue-derived cells to switch from a fibrogenetic to a chondroosteoprogenetic pattern of bone development. The quantity of induced bone is proportional to the dose of BMP/NCP in the range from 10 to 50 mg; immature rabbits produced larger deposits than mature rabbits in response to BMP/NCP. Preoperative local intramuscular injections of citric, edetic, or hyaluronic acids in specified concentrations markedly enhanced subperiosteal BMP/NCP-induced bone formation. The quantity of bovine or human BMP/NCP-induced bone formation in rabbits is also increased by very low-dose immunosuppression but not by bone mineral, tricalcium phosphate ceramic, inorganic calcium salts, or various space-occupying, unspecific chemical irritants. Although composities of BMP/NCP and allogeneic rabbit tendon collagen increased the quantity of bone in a parosteal site, in a heterotopic site the composite failed to induce bone formation. In a parosteal site, the conditions permitting BMP/NCP-induced bone formation develop, and the end product of the morphogenetic response is a duplicate diaphysis. How BMP reactivates the morphogenetic process in postfetal mesenchymal-type adventitial cells persisting in adult periosteum (including adjacent muscle attachments) is not known.

  5. [Bone morphogenetic proteins (BMP): clinical application for reconstruction of bone defects].

    PubMed

    Sierra-García, Gerardo Daniel; Castro-Ríos, Rocío; Gónzalez-Horta, Azucena; Lara-Arias, Jorge; Chávez-Montes, Abelardo

    2016-01-01

    Since the introduction of bone morphogenetic proteins, their use has become an invaluable ally for the treatment of bone defects. These proteins are potent growth factors, related to angiogenic and osteogenic activity. The osteoinductive capacity of recombinant bone morphogenetic protein (rhBMP) in the formation of bone and cartilage has been confirmed in in vitro studies and evaluated in clinical trials. To obtain a therapeutic effect, administration is systemic, by injection over the physiological dose. Among the disadvantages, ectopic bone formation or high morbidity in cases of spinal fusion is observed. In this review, the roles of bone morphogenetic proteins in bone repair and clinical applications are analyzed. These findings represent advances in the study of bone regeneration and application of growth factors for more predictable results.

  6. 75 FR 43533 - Medicare Program; Meeting of the Medicare Evidence Development and Coverage Advisory Committee...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-26

    ... and off-label use of bone morphogenetic proteins (BMPs). This meeting is open to the public in... use of bone morphogenetic proteins. Background information about this topic, including panel materials... appropriate organizations with expertise in the use of bone morphogenetic protein. II. Meeting Format This...

  7. Research on Navy-Related Combat Casualty Care Issues, Navy Operational-Related Injuries and Illnesses and Approaches to Enhance Navy/Marine Corps Personnel Combat Performance.

    DTIC Science & Technology

    1998-06-01

    role of bone morphogenetic protein (BMP) receptors in bone regeneration in periodontal tissues . Tissue samples for these studies are in the accrual...34 Characterization of Bone Morphogenetic Protein Receptors in Oral Tissues " collection of clinical samples will proceed in preparation for assay. • Relative to the...transcribed. • Relative to the project * Characterization of Bone Morphogenetic Protein Receptors in Oral Tissues ", collection of clinical samples is

  8. The Deep-Sea Natural Products, Biogenic Polyphosphate (Bio-PolyP) and Biogenic Silica (Bio-Silica), as Biomimetic Scaffolds for Bone Tissue Engineering: Fabrication of a Morphogenetically-Active Polymer

    PubMed Central

    Wang, Xiaohong; Schröder, Heinz C.; Feng, Qingling; Draenert, Florian; Müller, Werner E. G.

    2013-01-01

    Bone defects in human, caused by fractures/nonunions or trauma, gain increasing impact and have become a medical challenge in the present-day aging population. Frequently, those fractures require surgical intervention which ideally relies on autografts or suboptimally on allografts. Therefore, it is pressing and likewise challenging to develop bone substitution materials to heal bone defects. During the differentiation of osteoblasts from their mesenchymal progenitor/stem cells and of osteoclasts from their hemopoietic precursor cells, a lineage-specific release of growth factors and a trans-lineage homeostatic cross-talk via signaling molecules take place. Hence, the major hurdle is to fabricate a template that is functioning in a way mimicking the morphogenetic, inductive role(s) of the native extracellular matrix. In the last few years, two naturally occurring polymers that are produced by deep-sea sponges, the biogenic polyphosphate (bio-polyP) and biogenic silica (bio-silica) have also been identified as promoting morphogenetic on both osteoblasts and osteoclasts. These polymers elicit cytokines that affect bone mineralization (hydroxyapatite formation). In this manner, bio-silica and bio-polyP cause an increased release of BMP-2, the key mediator activating the anabolic arm of the hydroxyapatite forming cells, and of RANKL. In addition, bio-polyP inhibits the progression of the pre-osteoclasts to functionally active osteoclasts. Based on these findings, new bioinspired strategies for the fabrication of bone biomimetic templates have been developed applying 3D-printing techniques. Finally, a strategy is outlined by which these two morphogenetically active polymers might be used to develop a novel functionally active polymer. PMID:23528950

  9. Novel Therapy for Bone Regeneration in Large Segmental Defects

    DTIC Science & Technology

    2016-10-01

    reamed and nonreamed intrame- dullary nailing on fracture healing. Clin Orthop Relat Res. 1998;355(Suppl):S230–8. 37. Pape HC, Giannoudis PV. Fat embolism ...extension period (Year 4). 15. SUBJECT TERMS Bone healing, bone morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing, bone...Bone healing, bone morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing, bone regeneration, minipig, pig 3. OVERALL PROJECT

  10. High-dose bone morphogenetic protein-induced ectopic abdomen bone growth.

    PubMed

    Deutsch, Harel

    2010-02-01

    Infuse [bone morphogenetic protein (BMP)] is increasingly used in spinal fusion surgery. The authors report a rare complication of BMP use. This is a case report. A 55-year-old male underwent a thoracic T8 to the pelvis fusion for degenerative lumbar disc disease and pseudarthrosis at another institution. The procedure involved an anterior and posterior approach with the use of multiple units of BMP. The patient presented to our institution with complaints of weight loss, pain, tenderness, and increasing solid growth in the left lower quadrant several months after his surgery. A computed tomography revealed ectopic bone growth in the retroperitoneal area and pelvis contiguous to the anterior lumbar exposure. The anterior wound was re-explored, and a large sheet of ectopic bone was removed from the retroperitoneal space. We report a rare case of extraspinal ectopic bone growth because of the use of multiple packages of BMP. Copyright (c) 2010 Elsevier Inc. All rights reserved.

  11. Bone morphogenetic protein (BMP)1-3 enhances bone repair.

    PubMed

    Grgurevic, Lovorka; Macek, Boris; Mercep, Mladen; Jelic, Mislav; Smoljanovic, Tomislav; Erjavec, Igor; Dumic-Cule, Ivo; Prgomet, Stefan; Durdevic, Dragan; Vnuk, Drazen; Lipar, Marija; Stejskal, Marko; Kufner, Vera; Brkljacic, Jelena; Maticic, Drazen; Vukicevic, Slobodan

    2011-04-29

    Members of the astacin family of metalloproteinases such as human bone morphogenetic protein 1 (BMP-1) regulate morphogenesis by processing precursors to mature functional extracellular matrix (ECM) proteins and several growth factors including TGFβ, BMP2, BMP4 and GFD8. We have recently discovered that BMP1-3 isoform of the Bmp-1 gene circulates in the human plasma and is significantly increased in patients with acute bone fracture. We hypothesized that circulating BMP1-3 might have an important role in bone repair and serve as a novel bone biomarker. When administered systemically to rats with a long bone fracture and locally to rabbits with a critical size defect of the ulna, recombinant human BMP1-3 enhanced bone healing. In contrast, neutralization of the endogenous BMP1-3 by a specific polyclonal antibody delayed the bone union. Invitro BMP1-3 increased the expression of collagen type I and osteocalcin in MC3T3-E(1) osteoblast like cells, and enhanced the formation of mineralized bone nodules from bone marrow mesenchymal stem cells. We suggest that BMP1-3 is a novel systemic regulator of bone repair. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. A soluble bone morphogenetic protein type IA receptor increases bone mass and bone strength

    PubMed Central

    Baud’huin, Marc; Solban, Nicolas; Cornwall-Brady, Milton; Sako, Dianne; Kawamoto, Yoshimi; Liharska, Katia; Lath, Darren; Bouxsein, Mary L.; Underwood, Kathryn W.; Ucran, Jeffrey; Kumar, Ravindra; Pobre, Eileen; Grinberg, Asya; Seehra, Jasbir; Canalis, Ernesto; Pearsall, R. Scott; Croucher, Peter I.

    2012-01-01

    Diseases such as osteoporosis are associated with reduced bone mass. Therapies to prevent bone loss exist, but there are few that stimulate bone formation and restore bone mass. Bone morphogenetic proteins (BMPs) are members of the TGFβ superfamily, which act as pleiotropic regulators of skeletal organogenesis and bone homeostasis. Ablation of the BMPR1A receptor in osteoblasts increases bone mass, suggesting that inhibition of BMPR1A signaling may have therapeutic benefit. The aim of this study was to determine the skeletal effects of systemic administration of a soluble BMPR1A fusion protein (mBMPR1A–mFc) in vivo. mBMPR1A–mFc was shown to bind BMP2/4 specifically and with high affinity and prevent downstream signaling. mBMPR1A–mFc treatment of immature and mature mice increased bone mineral density, cortical thickness, trabecular bone volume, thickness and number, and decreased trabecular separation. The increase in bone mass was due to an early increase in osteoblast number and bone formation rate, mediated by a suppression of Dickkopf-1 expression. This was followed by a decrease in osteoclast number and eroded surface, which was associated with a decrease in receptor activator of NF-κB ligand (RANKL) production, an increase in osteoprotegerin expression, and a decrease in serum tartrate-resistant acid phosphatase (TRAP5b) concentration. mBMPR1A treatment also increased bone mass and strength in mice with bone loss due to estrogen deficiency. In conclusion, mBMPR1A–mFc stimulates osteoblastic bone formation and decreases bone resorption, which leads to an increase in bone mass, and offers a promising unique alternative for the treatment of bone-related disorders. PMID:22761317

  13. Bone morphogenetic protein and bone metastasis, implication and therapeutic potential.

    PubMed

    Ye, Lin; Mason, Malcolm D; Jiang, Wen G

    2011-01-01

    Bone metastasis is one of the most common and severe complications in advanced malignancies, particularly in the three leading cancers; breast cancer, prostate cancer and lung cancer. It is currently incurable and causes severe morbidities, including bone pain, hypercalcemia, pathological fracture, spinal cord compression and consequent paralysis. However, the mechanisms underlying the development of bone metastasis remain largely unknown. Bone morphogenetic proteins (BMPs) belong to the TGF-beta superfamily and are pluripotent factors involved in the regulation of embryonic development and postnatal homeostasis of various organs and tissues, by controlling cellular differentiation, proliferation and apoptosis. Since they are potent regulators for bone formation, there is an increasing interest to investigate BMPs and their roles in bone metastasis. BMPs have been implicated in various neoplasms, at both primary and secondary tumors, particularly skeletal metastasis. Recently studies have also suggested that BMP signaling and their antagonists play pivotal roles in bone metastasis. In this review, we discuss the current knowledge of aberrations of BMPs which have been indicated in tumor progression, and particularly in the development of bone metastasis.

  14. GDF9 and BMP15 Expressions and Fine Structure Changes During Folliculogenesis in Polycystic Ovary Syndrome.

    PubMed

    Karagül, Meryem İlkay; Aktaş, Savaş; Coşkun Yılmaz, Banu; Yılmaz, Mustafa; Orekici Temel, Gülhan

    2018-01-20

    Polycystic ovary syndrome is the most frequently seen endocrine disorder in women of reproductive age with a prevalence of about 10%. To investigate the efficiency of growth differentiation factor 9 and bone morphogenetic protein 15 during folliculogenesis in a dehydroepiandrosterone-induced mouse Polycystic ovary syndrome model. Animal experimentation. Mice were divided into 3 groups: control, vehicle and Polycystic ovary syndrome. Polycystic ovary syndrome model mice were developed by the injection of dehydroepiandrosterone dissolved in 0.1 mL of sesame oil. Ovarian tissues were examined for growth differentiation factor 9 and bone morphogenetic protein 15 using immunofluorescent labelling and electron microscopic examinations. The immunoreactivity of growth differentiation factor 9 and bone morphogenetic protein 15 proteins decreased (p<0.05) in the Polycystic ovary syndrome group (27.73±8.43 and 24.85±7.03, respectively) compared with the control group (33.72±11.22 and 31.12±11.05, respectively) and vehicle group (33.95±10.75 and 29.99±10.72, respectively). Apoptotic changes were observed in granulosa cells, lipid vacuoles increased in Theca cells and thickening and irregularities were noted in the basal lamina of granulosa cells. An increased electron density in the zona pellucida in some of the multilaminar primary and secondary follicles in the Polycystic ovary syndrome model was also observed at the ultrastructural level. These results suggest that the decrease in the growth differentiation factor 9 and bone morphogenetic protein 15 expression initiated at the primary follicle stage effect the follicle development and zona pellucida structure and may cause subfertility or infertility in Polycystic ovary syndrome.

  15. In vitro bone formation using muscle-derived cells: a new paradigm for bone tissue engineering using polymer-bone morphogenetic protein matrices.

    PubMed

    Lu, Helen H; Kofron, Michelle D; El-Amin, Saadiq F; Attawia, Mohammed A; Laurencin, Cato T

    2003-06-13

    Over 800,000 bone grafting procedures are performed in the United States annually, creating a demand for viable alternatives to autogenous bone, the grafting standard in osseous repair. The objective of this study was to examine the efficacy of a BMP-polymer matrix in inducing the expression of the osteoblastic phenotype and in vitro bone formation by muscle-derived cells. Specifically, we evaluated the ability of bone morphogenetic protein-7 (BMP-7), delivered from a poly(lactide-co-glycolide) (PLAGA) matrix, to induce the differentiation of cells derived from rabbit skeletal muscle into osteoblast-like cells and subsequently form mineralized tissue. Results confirmed that muscle-derived cells attached and proliferated on the PLAGA substrates. BMP-7 released from PLAGA induced the muscle-derived cells to increase bone marker expression and form mineralized cultures. These results demonstrate the efficacy of a BMP-polymer matrix in inducing the expression of the osteoblastic phenotype by muscle-derived cells and present a new paradigm for bone tissue engineering.

  16. Bone morphogenetic protein type IA receptor signaling regulates postnatal osteoblast function and bone remodeling.

    PubMed

    Mishina, Yuji; Starbuck, Michael W; Gentile, Michael A; Fukuda, Tomokazu; Kasparcova, Viera; Seedor, J Gregory; Hanks, Mark C; Amling, Michael; Pinero, Gerald J; Harada, Shun-ichi; Behringer, Richard R

    2004-06-25

    Bone morphogenetic proteins (BMPs) function during various aspects of embryonic development including skeletogenesis. However, their biological functions after birth are less understood. To investigate the role of BMPs during bone remodeling, we generated a postnatal osteoblast-specific disruption of Bmpr1a that encodes the type IA receptor for BMPs in mice. Mutant mice were smaller than controls up to 6 months after birth. Irregular calcification and low bone mass were observed, but there were normal numbers of osteoblasts. The ability of the mutant osteoblasts to form mineralized nodules in culture was severely reduced. Interestingly, bone mass was increased in aged mutant mice due to reduced bone resorption evidenced by reduced bone turnover. The mutant mice lost more bone after ovariectomy likely resulting from decreased osteoblast function which could not overcome ovariectomy-induced bone resorption. In organ culture of bones from aged mice, ablation of the Bmpr1a gene by adenoviral Cre recombinase abolished the stimulatory effects of BMP4 on the expression of lysosomal enzymes essential for osteoclastic bone resorption. These results demonstrate essential and age-dependent roles for BMP signaling mediated by BMPRIA (a type IA receptor for BMP) in osteoblasts for bone remodeling.

  17. Effectiveness of recombinant human bone morphogenetic protein-7 in the management of congenital pseudoarthrosis of the tibia: a randomised controlled trial.

    PubMed

    Das, Sakti Prasad; Ganesh, Shankar; Pradhan, Sudhakar; Singh, Deepak; Mohanty, Ram Narayan

    2014-09-01

    Despite the popularity and an increased use of bone morphogenetic protein to improve bone healing in patients with congenital pseudoarthrosis of the tibia (CPT), no previous study has compared its efficacy against any other procedure. We randomised 20 consecutive patients (mean age 4.1 years) with CPT (Crawford type IV) associated with neurofibromatosis type 1(NF1) and no previous history of surgery into two groups. Group 1 received recombinant human bone morphogenetic protein-7 (rhBMP-7) along with intramedullary Kirschner (K)-wire fixation and autologous bone grafting; group 2 received only K wire and grafting. Outcome measures were time to achieve union, Johnston grade, tibial length and the American Orthopaedic Foot and Ankle Society (AOFAS) score, which were evaluated preoperatively and at five year follow-up. Study results showed that patients in group 1 achieved primary bone union at a mean of 14.5 months [standard error (SE) 5.2], whereas group 2 took a mean of 17.11 months (SE 5.0). However, the log-rank test showed no difference in healing times between groups at all time points (P = 0.636). There was a statistically significant pre- to post operative improvement (P < 0.05) within groups for the other outcome measures. In a five year follow-up, these results suggest that rh-BMP-7 and autologous bone grafting is no better than autologous grafting alone.

  18. [Experimental study on repair of the defect of the pars interarticularis in rat with bone morphogenetic protein and fibrin glue].

    PubMed

    Nakamura, T

    1992-07-01

    The possibility of repairing the defect of the pars interarticularis (pars defect) with Bone Morphogenetic Protein (BMP) and fibrin glue was studied. The pars defect established in the 5th lumbar vertebra of Wistar rat was treated with surgical implantation of a composite consisting of BMP, fibrin glue and autologous cancellous bone. At 3, 6, 9 and 12 weeks after implantation, the osteoinductive activity in the pars defect was observed histologically and compared with that of other composite implants such as BMP with fibrin glue, autologous cancellous bone alone and autologous cancellous bone with fibrin glue. Although perfect bone fusion was not obtained with any of the composites employed, a significant increase in bone formation was seen in a composite of BMP, fibrin glue and autologous cancellous bone (p less than 0.01) as compared with that seen in the others. Consequently, implantation of BMP and fibrin glue combined with some biomaterials which support osteo-induction of BMP and stabilize the pars defect might be successfully applied to repair the pars defect.

  19. Bone morphogenetic protein-2 and bone therapy: successes and pitfalls.

    PubMed

    Poon, Bonnie; Kha, Tram; Tran, Sally; Dass, Crispin R

    2016-02-01

    Bone morphogenetic proteins (BMPs), more specifically BMP-2, are being increasingly used in orthopaedic surgery due to advanced research into osteoinductive factors that may enhance and improve bone therapy. There are many areas in therapy that BMP-2 is being applied to, including dental treatment, open tibial fractures, cancer and spinal surgery. Within these areas of treatment, there are many reports of successes and pitfalls. This review explores the use of BMP-2 and its successes, pitfalls and future prospects in bone therapy. The PubMed database was consulted to compile this review. With successes in therapy, there were descriptions of a more rapid healing time with no signs of rejection or infection attributed to BMP-2 treatment. Pitfalls included BMP-2 'off-label' use, which lead to various adverse effects. Our search highlighted that optimising treatment with BMP-2 is a direction that many researchers are exploring, with areas of current research interest including concentration and dose of BMP-2, carrier type and delivery. © 2015 Royal Pharmaceutical Society.

  20. Bone Morphogenetic Protein-2 Promotes Human Mesenchymal Stem Cell Survival and Resultant Bone Formation When Entrapped in Photocrosslinked Alginate Hydrogels.

    PubMed

    Ho, Steve S; Vollmer, Nina L; Refaat, Motasem I; Jeon, Oju; Alsberg, Eben; Lee, Mark A; Leach, J Kent

    2016-10-01

    There is a substantial need to prolong cell persistence and enhance functionality in situ to enhance cell-based tissue repair. Bone morphogenetic protein-2 (BMP-2) is often used at high concentrations for osteogenic differentiation of mesenchymal stem cells (MSCs) but can induce apoptosis. Biomaterials facilitate the delivery of lower doses of BMP-2, reducing side effects and localizing materials at target sites. Photocrosslinked alginate hydrogels (PAHs) can deliver osteogenic materials to irregular-sized bone defects, providing improved control over material degradation compared to ionically cross-linked hydrogels. It is hypothesized that the delivery of MSCs and BMP-2 from a PAH increases cell persistence by reducing apoptosis, while promoting osteogenic differentiation and enhancing bone formation compared to MSCs in PAHs without BMP-2. BMP-2 significantly decreases apoptosis and enhances survival of photoencapsulated MSCs, while simultaneously promoting osteogenic differentiation in vitro. Bioluminescence imaging reveals increased MSC survival when implanted in BMP-2 PAHs. Bone defects treated with MSCs in BMP-2 PAHs demonstrate 100% union as early as 8 weeks and significantly higher bone volumes at 12 weeks, while defects with MSC-entrapped PAHs alone do not fully bridge. This study demonstrates that transplantation of MSCs with BMP-2 in PAHs achieves robust bone healing, providing a promising platform for bone repair. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Promising efficacy of Escherichia coli recombinant human bone morphogenetic protein-2 in collagen sponge for ectopic and orthotopic bone formation and comparison with mammalian cell recombinant human bone morphogenetic protein-2.

    PubMed

    Kim, In Sook; Lee, Eui Nam; Cho, Tae Hyung; Song, Yun Mi; Hwang, Soon Jung; Oh, Ji Hye; Park, Eun Kyung; Koo, Tai Young; Seo, Young-Kwon

    2011-02-01

    Nonglycosylated recombinant human bone morphogenetic protein (rhBMP)-2 prepared in Escherichia coli (E. coli rhBMP-2) has recently been considered as an alternative to mammalian cell rhBMP-2. However, its clinical use is still limited owing to lack of evidence for osteogenic activity comparable with that of mammalian cell rhBMP-2 via microcomputed tomography-based analysis. Therefore, this study aimed to evaluate the ability of E. coli rhBMP-2 in absorbable collagen sponge to form ectopic and orthotopic bone and to compare it to that of mammalian rhBMP-2. In vitro investigation was performed to study osteoblast differentiation of human mesenchymal stromal cells. Both types of rhBMP-2 enhanced proliferation, alkaline phosphatase activity, and matrix mineralization of human mesenchymal stromal cells at similar levels. Similar tendencies were observed in microcomputed tomography analysis, which determined bone volume, fractional bone volume, trabecular thickness, trabecular separation, bone mineral density, and other characteristics. Histology from an in vivo osteoinductivity test and from a rat calvarial defect model demonstrated a dose-dependent increase in local bone formation. The E. coli rhBMP-2 group (5 μg) not only induced complete regeneration of an 8-mm critical-sized defect at 4 weeks, but also led to new bone with the same bone mineral density as normal bone at 8 weeks, with the same efficiency as that of mammalian cell rhBMP-2 (5 μg). These uniformly favorable results provide evidence that the osteogenic activity of E. coli rhBMP-2 is not inferior to that of mammalian cell rhBMP-2 despite its low solubility and lack of gylcosylation. These results suggest that the application of E. coli rhBMP-2 in absorbable collagen sponge may be a promising equivalent to mammalian cell rhBMP-2 in bone tissue engineering.

  2. Combination of bone morphogenetic protein-2 plasmid DNA with chemokine CXCL12 creates an additive effect on bone formation onset and volume.

    PubMed

    Wegman, F; Poldervaart, M T; van der Helm, Y J; Oner, F C; Dhert, W J; Alblas, J

    2015-07-27

    Bone morphogenetic protein-2 (BMP-2) gene delivery has shown to induce bone formation in vivo in cell-based tissue engineering. In addition, the chemoattractant stromal cell-derived factor-1α (SDF-1α, also known as CXCL12) is known to recruit multipotent stromal cells towards its release site where it enhances vascularisation and possibly contributes to osteogenic differentiation. To investigate potential cooperative behaviour for bone formation, we investigated combined release of BMP-2 and SDF-1α on ectopic bone formation in mice. Multipotent stromal cell-seeded and cell-free constructs with BMP-2 plasmid DNA and /or SDF-1α loaded onto gelatin microparticles, were implanted subcutaneously in mice for a period of 6 weeks. Histological analysis and histomorphometry revealed that the onset of bone formation and the formed bone volume were both enhanced by the combination of BMP-2 and SDF-1α compared to controls in cell-seeded constructs. Samples without seeded multipotent stromal cells failed to induce any bone formation. We conclude that the addition of stromal cell-derived factor-1α to a cell-seeded alginate based bone morphogenetic protein-2 plasmid DNA construct has an additive effect on bone formation and can be considered a promising combination for bone regeneration.

  3. Fine mapping of the human bone morphogenetic protein-4 gene (BMP4) to chromosome 14q22-q23 by in situ hybridization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wijngaard, A. van den; Boersma, C.J.C.; Olijve, W.

    Bone morphogenetic protein-4 (BMP-4) is a member of the transforming growth factor-{beta} (TGF-{beta}) superfamily and is involved in morphogenesis and bone cell differentiation. Recombinant BMP-4 can induce ectopic cartilage and bone formation when implanted subcutaneously or intramuscularly in rodents. This ectopic bone formation process resembles the process of bone formation during embryogenesis and fracture healing. A cosmid clone containing the complete human bone morphogenetic protein-4 gene (BMP4) was isolated (details to be published elsewhere) and used as a probe to determine the precise chromosomal localization of the human BMP4 gene. This cosmid clone was labeled with biotin-14-dATP and hybridized inmore » situ to chromosomal preparations of metaphase cells as described previously. In 20 metaphase preparations, an intense and specific fluorescence signal (FITC) was detected on the q arm of chromosome 14. The DAPI-counterstained chromosomes were computer-converted into GTG-like banding patterns, allowing the regional localization of BMP4 within 14q22-q23. 10 refs., 1 fig.« less

  4. Intracellular amyloid beta expression leads to dysregulation of the mitogen-activated protein kinase and bone morphogenetic protein-2 signaling axis

    PubMed Central

    Cruz, Eric; Kumar, Sushil; Yuan, Li; Arikkath, Jyothi

    2018-01-01

    Alzheimer’s disease (AD) is a neurodegenerative syndrome classically depicted by the parenchymal accumulation of extracellular amyloid beta plaques. However, recent findings suggest intraneuronal amyloid beta (iAβ1–42) accumulation precedes extracellular deposition. Furthermore, the pathologic increase in iAβ1–42 has been implicated in dysregulation of cellular mechanisms critically important in axonal transport. Owing to neuronal cell polarity, retrograde and anterograde axonal transport are essential trafficking mechanism necessary to convey membrane bound neurotransmitters, neurotrophins, and endosomes between soma and synaptic interfaces. Although iAβ1–42 disruption of axonal transport has been implicated in dysregulation of neuronal synaptic transmission, the role of iAβ1–42 and its influence on signal transduction involving the mitogen-activated protein kinase (MAPK) and morphogenetic signaling axis are unknown. Our biochemical characterization of intracellular amyloid beta accumulation on MAPK and morphogenetic signaling have revealed increased iAβ1–42 expression leads to significant reduction in ERK 1/2 phosphorylation and increased bone morphogenetic protein 2 dependent Smad 1/5/8 phosphorylation. Furthermore, rescue of iAβ1–42 mediated attenuation of MAPK signaling can be accomplished with the small molecule PLX4032 as a downstream enhancer of the MAPK pathway. Consequently, our observations regarding the dysregulation of these gatekeepers of neuronal viability may have important implications in understanding the iAβ1–42 mediated effects observed in AD. PMID:29470488

  5. The Bone Morphogenetic Protein Type Ib Receptor Is a Major Mediator of Glial Differentiation and Cell Survival in Adult Hippocampal Progenitor Cell Culture

    PubMed Central

    Brederlau, A.; Faigle, R.; Elmi, M.; Zarebski, A.; Sjöberg, S.; Fujii, M.; Miyazono, K.; Funa, K.

    2004-01-01

    Bone morphogenetic proteins (BMPs) act as growth regulators and inducers of differentiation. They transduce their signal via three different type I receptors, termed activin receptor-like kinase 2 (Alk2), Alk3, or bone morphogenetic protein receptor Ia (BMPRIa) and Alk6 or BMPRIb. Little is known about functional differences between the three type I receptors. Here, we have investigated consequences of constitutively active (ca) and dominant negative (dn) type I receptor overexpression in adult-derived hippocampal progenitor cells (AHPs). The dn receptors have a nonfunctional intracellular but functional extracellular domain. They thus trap BMPs that are endogenously produced by AHPs. We found that effects obtained by overexpression of dnAlk2 and dnAlk6 were similar, suggesting similar ligand binding patterns for these receptors. Thus, cell survival was decreased, glial fibrillary acidic protein (GFAP) expression was reduced, whereas the number of oligodendrocytes increased. No effect on neuronal differentiation was seen. Whereas the expression of Alk2 and Alk3 mRNA remained unchanged, the Alk6 mRNA was induced after impaired BMP signaling. After dnAlk3 overexpression, cell survival and astroglial differentiation increased in parallel to augmented Alk6 receptor signaling. We conclude that endogenous BMPs mediate cell survival, astroglial differentiation and the suppression of oligodendrocytic cell fate mainly via the Alk6 receptor in AHP culture. PMID:15194807

  6. Cyst-Like Osteolytic Formations in Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) Augmented Sheep Spinal Fusion.

    PubMed

    Pan, Hsin Chuan; Lee, Soonchul; Ting, Kang; Shen, Jia; Wang, Chenchao; Nguyen, Alan; Berthiaume, Emily A; Zara, Janette N; Turner, A Simon; Seim, Howard B; Kwak, Jin Hee; Zhang, Xinli; Soo, Chia

    2017-07-01

    Multiple case reports using recombinant human bone morphogenetic protein-2 (rhBMP-2) have reported complications. However, the local adverse effects of rhBMP-2 application are not well documented. In this report we show that, in addition to promoting lumbar spinal fusion through potent osteogenic effects, rhBMP-2 augmentation promotes local cyst-like osteolytic formations in sheep trabecular bones that have undergone anterior lumbar interbody fusion. Three months after operation, conventional computed tomography showed that the trabecular bones of the rhBMP-2 application groups could fuse, whereas no fusion was observed in the control group. Micro-computed tomography analysis revealed that the core implant area's bone volume fraction and bone mineral density increased proportionately with rhBMP-2 dose. Multiple cyst-like bone voids were observed in peri-implant areas when using rhBMP-2 applications, and these sites showed significant bone mineral density decreases in relation to the unaffected regions. Biomechanically, these areas decreased in strength by 32% in comparison with noncystic areas. Histologically, rhBMP-2-affected void sites had an increased amount of fatty marrow, thinner trabecular bones, and significantly more adiponectin- and cathepsin K-positive cells. Despite promoting successful fusion, rhBMP-2 use in clinical applications may result in local adverse structural alterations and compromised biomechanical changes to the bone. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  7. Atrophic Mandible Fractures: Are Bone Grafts Necessary? An Update.

    PubMed

    Castro-Núñez, Jaime; Cunningham, Larry L; Van Sickels, Joseph E

    2017-11-01

    The management of atrophic mandibular fractures poses a challenge because of anatomic variations and medical comorbidities associated with elderly patients. The purpose of this article is to review and update the literature regarding the management of atrophic mandible fractures using load-bearing reconstruction plates placed without bone grafts. We performed a review of the English-language literature looking for atrophic mandibular fractures with or without continuity defects and reconstruction without bone grafts. Included are 2 new patients from our institution who presented with fractures of their atrophic mandibles and had continuity defects and infections. Both patients underwent reconstruction with a combination of a reconstruction plate, recombinant human bone morphogenetic protein 2, and tricalcium phosphate. This study was approved as an "exempt study" by the Institutional Review Board at the University of Kentucky. This investigation observed the Declaration of Helsinki on medical protocol and ethics. Currently, the standard of care to manage atrophic mandibular fractures with or without a continuity defect is a combination of a reconstruction plate plus autogenous bone graft. However, there is a need for an alternative option for patients with substantial comorbidities. Bone morphogenetic proteins, with or without additional substances, appear to be a choice. In our experience, successful healing occurred in patients with a combination of a reconstruction plate, recombinant human bone morphogenetic protein 2, and tricalcium phosphate. Whereas primary reconstruction of atrophic mandibular fractures with reconstruction plates supplemented with autogenous bone graft is the standard of care, in selected cases in which multiple comorbidities may influence local and/or systemic outcomes, bone morphogenetic proteins and tricalcium phosphate can be used as a predictable alternative to autogenous grafts. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  8. Bone Regeneration Using Bone Morphogenetic Proteins and Various Biomaterial Carriers

    PubMed Central

    Sheikh, Zeeshan; Javaid, Mohammad Ahmad; Hamdan, Nader; Hashmi, Raheel

    2015-01-01

    Trauma and disease frequently result in fractures or critical sized bone defects and their management at times necessitates bone grafting. The process of bone healing or regeneration involves intricate network of molecules including bone morphogenetic proteins (BMPs). BMPs belong to a larger superfamily of proteins and are very promising and intensively studied for in the enhancement of bone healing. More than 20 types of BMPs have been identified but only a subset of BMPs can induce de novo bone formation. Many research groups have shown that BMPs can induce differentiation of mesenchymal stem cells and stem cells into osteogenic cells which are capable of producing bone. This review introduces BMPs and discusses current advances in preclinical and clinical application of utilizing various biomaterial carriers for local delivery of BMPs to enhance bone regeneration. PMID:28788032

  9. Synergistic effects of dimethyloxallyl glycine and recombinant human bone morphogenetic protein-2 on repair of critical-sized bone defects in rats

    PubMed Central

    Qi, Xin; Liu, Yang; Ding, Zhen-yu; Cao, Jia-qing; Huang, Jing-huan; Zhang, Jie-yuan; Jia, Wei-tao; Wang, Jing; Liu, Chang-sheng; Li, Xiao-lin

    2017-01-01

    In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration. PMID:28230059

  10. Synergistic effects of dimethyloxallyl glycine and recombinant human bone morphogenetic protein-2 on repair of critical-sized bone defects in rats

    NASA Astrophysics Data System (ADS)

    Qi, Xin; Liu, Yang; Ding, Zhen-Yu; Cao, Jia-Qing; Huang, Jing-Huan; Zhang, Jie-Yuan; Jia, Wei-Tao; Wang, Jing; Liu, Chang-Sheng; Li, Xiao-Lin

    2017-02-01

    In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration.

  11. Evaluation of bone regeneration with biphasic calcium phosphate substitute implanted with bone morphogenetic protein 2 and mesenchymal stem cells in a rabbit calvarial defect model.

    PubMed

    Kim, Beom-Su; Choi, Moon-Ki; Yoon, Jung-Hoon; Lee, Jun

    2015-07-01

    The aim of this study was to evaluate the in vivo osteogenic potential of biphasic calcium phosphate (BCP), bone morphogenetic protein 2 (BMP-2), and/or mesenchymal stem cell (MSC) composites by using a rabbit calvarial defect model. Bone formation was assessed by using three different kinds of implants in rabbit calvarial defects, BCP alone, BCP/recombinant human (rh) BMP-2, and BCP/rhBMP-2/MSCs composite. The implants were harvested after 2 or 8 weeks, and the area of new bone formation was quantified by micro-computed tomography (micro-CT) and histologic studies. The highest bone formation was achieved with the BCP/rhBMP-2/MSCs treatment, and it was significantly higher than that achieved with the empty or BCP-alone treatment. The quantity of new bone at 8 weeks was greater than at 4 weeks in each group. The relative density of osteocalcin immunoreactivity also increased during this interval. These results indicate that the combination of BCP, rhBMP-2, and MSCs synergistically enhances osteogenic potential during the early healing period and could be used as a bone graft substitute. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. The extraction and measurement of bone morphogenetic protein 7 from bovine cortical bone as a function of particle size.

    PubMed

    Pietrzak, William S; Ali, Saba N

    2015-01-01

    Bone morphogenetic proteins (BMPs), present in parts per billion in bone, endow demineralized bone matrix (DBM) with osteoinductive properties suitable for clinical use. Although BMPs are mainly associated with bone matrix, they also associate with other bone compartments as well, including the mineral phase. The purpose of this study was to gain a more complete understanding of the distribution of BMPs in undemineralized bone. Eleven discrete particle size ranges of bovine cortical bone were prepared, ranging between less than 25 μm and 600 to 710 μm for the smallest and largest sizes, respectively. The bone was extracted with 4-M guanidine-HCl/0.05-M Tris-HCl, and the amount of BMP-7 released was measured with enzyme-linked immunosorbant assay. In addition, 106- to 710-μm bone particles were demineralized and similarly extracted for comparison. The measured BMP-7 content of the DBM was 24.6 ± 1.56 ng/g. The values for bone increased nonlinearly with decreasing particle size, ranging from 1.13 ± 0.50 ng/g for the 600- to 710-μm particles to 4.18 ± 1.14 ng/g for the less than 25-μm particles (P < 0.001). However, modeling the bone particles as solid spheres to estimate total surface area showed that the extracted BMP-7 per unit area was greater for larger particle sizes. These seemingly opposing results suggest that BMPs may become proportionally damaged or altered in response to the increased forces required to generate smaller particles and, as such, may not be detectable with enzyme-linked immunosorbant assay. In addition, minimization of bone particle size is not an effective strategy to approach the BMP availability of DBM.

  13. Activation of the PI3K/Akt pathway mediates bone morphogenetic protein 2-induced invasion of pancreatic cancer cells Panc-1.

    PubMed

    Chen, Xiong; Liao, Jie; Lu, YeBin; Duan, XiaoHui; Sun, WeiJia

    2011-06-01

    Bone morphogenetic proteins (BMPs) signaling has an emerging role in pancreatic cancer. However, because of the multiple effects of different BMPs, no final conclusions have been made as to the role of BMPs in pancreatic cancer. In our studies, we have focused on bone morphogenetic protein 2(BMP-2) because it induces an epithelial to mesenchymal transition (EMT) and accelerates invasion in the human pancreatic cancer cell line Panc-1. It has been reported that the phosphatidylinositol 3-kinase (PI3K)/Akt pathway mediates invasion of gastric and colon cancer cells, which is unrevealed in pancreatic cancer cells. The objective of our study was to investigate whether BMP-2 mediated invasion might pass through the PI3K/Akt pathway. Our results show that expression of phosphorylation of Akt was increased by treatment with BMP-2, but not Noggin, a BMP-2 antagonist. Then pretreatment of Panc-1 cells with LY294002, an inhibitor of the PI3K/AKT pathway, significantly inhibited BMP-2-induced EMT and invasiveness. The data suggest that BMP-2 accelerates invasion of panc-1 cells via the PI3K/AKT pathway in panc-1 cells, which gives clues to searching new therapy targets in advanced pancreatic cancer.

  14. Bone morphogenetic protein use in spine surgery-complications and outcomes: a systematic review.

    PubMed

    Faundez, Antonio; Tournier, Clément; Garcia, Matthieu; Aunoble, Stéphane; Le Huec, Jean-Charles

    2016-06-01

    Because of significant complications related to the use of autologous bone grafts in spinal fusion surgery, bone substitutes and growth factors such as bone morphogenetic protein (BMP) have been developed. One of them, recombinant human (rh) BMP-2, has been approved by the Food and Drug Administration (FDA) for use under precise conditions. However, rhBMP-2-related side effects have been reported, used in FDA-approved procedures, but also in off-label use.A systematic review of clinical data was conducted to analyse the rhBMP-2-related adverse events (AEs), in order to assess their prevalence and the associated surgery practices. Medline search with keywords "bone morphogenetic protein 2", "lumbar spine", "anterolateral interbody fusion" (ALIF) and the filter "clinical trial". FDA published reports were also included. Study assessment was made by authors (experienced spine surgeons), based on quality of study designs and level of evidence. Extensive review of randomised controlled trials (RCTs) and controlled series published up to the present point, reveal no evidence of a significant increase of AEs related to rhBMP-2 use during ALIF surgeries, provided that it is used following FDA guidelines. Two additional RCTs performed with rhBMP-2 in combination with allogenic bone dowels reported increased bone remodelling in BMP-treated patients. This AE was transient and had no consequence on the clinical outcome of the patients. No other BMP-related AEs were reported in these studies. This literature review confirms that the use of rhBMP-2 following FDA-approved recommendations (i.e. one-level ALIF surgery with an LT-cage) is safe. The rate of complications is low and the AEs had been identified by the FDA during the pre-marketing clinical trials. The clinical efficiency of rhBMP-2 is equal or superior to that of allogenic or autologous bone graft in respect to fusion rate, low back pain disability, patient satisfaction and rate of re-operations. For all other off-label use, the safety and effectiveness of rhBMP-2 have not been established, and further RCTs with high level of evidence are required.

  15. Accelerators of Osteogenesis by Recombinant Human Bone Morphogenetic Protein-2

    PubMed Central

    Okubo, Yasunori; Kusumoto, Kenji; Bessho, Kazuhisa

    2007-01-01

    Bone morphogenetic protein (BMP) appears to be one of the most promising cytokine and for clinical use in reconstructive surgery for bony defects and augmentation. To evaluate the effect of basic fibroblast growth factor (bFGF), FK506, elcatonin, and hyperbaric oxygenation (HBO) on osteoinduction by recombinant human bone morphogenetic protein-2 (rhBMP-2), 2 or 5 μg of rhBMP-2 was implanted into intramuscular sites of rats. At 21 days after implantation, the osteoinductive activity in the treatment group and control group was compared radiographically, biochemically, and histologically. The amount of new bone in the treatment group was significantly greater than that in the control group. The alkaline phosphatase activity and calcium content in the treatment group were significantly higher than those in the control group. These results suggest that bFGF, FK506, elcatonin, and HBO accelerated the activity and rate of osteoinduction by rhBMP2. These results may be useful when BMP is applied clinically in near future. PMID:21901062

  16. In anemia of multiple myeloma hepcidin is induced by increased bone-morphogenetic protein-2

    USDA-ARS?s Scientific Manuscript database

    Hepcidin is the principal iron-regulatory hormone and pathogenic factor in anemia of inflammation. Patients with multiple myeloma (MM) frequently present with anemia. We showed that MM patients had increased serum hepcidin, which inversely correlated with hemoglobin, suggesting that hepcidin contrib...

  17. Associations between variants of bone morphogenetic protein 7 gene and growth traits in chickens.

    PubMed

    Wang, Yan; Guo, Fuyou; Qu, Hao; Luo, Chenglong; Wang, Jie; Shu, Dingming

    2018-04-18

    1. Enhancing bone strength to solve leg disorders in poultry has become an important goal in broiler production. 2. Bone morphogenetic protein 7 (BMP7), a member of the BMP family, represents an attractive therapeutic target for bone regeneration in humans and plays critical roles in skeletal development. 3. The objective of this study was to investigate the relationship between BMP7 gene expression, single nucleotide polymorphisms (SNPs) and growth traits in chickens. Here, a SNP (c.1995T>C) in the chicken (Gallus gallus) BMP7 gene was identified, that was associated with growth and carcass traits. 4. Genotyping revealed that the T allele occurred more frequently in breeds with high growth rates, whereas the C allele was predominant in those with low growth rates. The expression level of BMP7 in the thigh bone of birds with the TT genotype was significantly higher than in those with the CC genotype at 21, 42 and 91 days of age. 5. These findings suggest that selecting the birds with the TT genotype of SNP c.1995T>C could improve bone growth, could reduce leg disorders in fast-growing birds. The SNP c.1995T>C may serve as a selective marker for improving bone growth and increasing the consistency of body weights in poultry breeding.

  18. Heterodimeric BMP-2/7 Antagonizes the Inhibition of All-Trans Retinoic Acid and Promotes the Osteoblastogenesis

    PubMed Central

    Bi, Wenjuan; Gu, Zhiyuan; Zheng, Yuanna; Zhang, Xiao; Guo, Jing; Wu, Gang

    2013-01-01

    Objectives Hypervitaminosis A and alcoholism can result in a low mineral density and compromised regenerative capacity of bone, thus delaying implant osteointegration. The inhibitory effect of all-trans retinoic acid on osteoblastogenesis is considered to be one of the mechanisms. We hypothesized that heterodimeric bone morphogenetic protein-2/7 could antagonize all-trans retinoic acid and enhance osteoblastogenesis, with an aim to accelerate and enhance bone regeneration and implant osteointegration. Materials and Methods We applied 5 ng/ml or 50 ng/ml bone morphogenetic protein-2/7 to restore the osteoblastogenesis of pre-osteoblasts (MC3T3-E1 cell line) that was inhibited by 1 µM all-trans retinoic acid. We evaluated the efficacy by assessing cell numbers (proliferation), alkaline phosphatase activity (a marker for early differentiation), osteocalcin (a marker for late differentiation), calcium deposition (a marker for final mineralization) and the expression of osteoblastogenic genes (such as Runx2, Collagen Ia, alkaline phosphatase and osteocalcin) at different time points. Results All-trans retinoic acid significantly inhibited the expression of all the tested osteoblastogenic genes and proteins except alkaline phosphatase activity. In the presence of ATRA, 50 ng/ml bone morphogenetic protein-2/7 not only completely restored but also significantly enhanced all the osteoblastogenic genes and proteins. On the 28th day, mineralization was completely inhibited by all-trans retinoic acid. In contrast, 50 ng/ml BMP-2/7 could antagonize ATRA and significantly enhance the mineralization about 2.5 folds in comparison with the control treatment (no ATRA, no BMP2/7). Conclusions Heterodimeric bone morphogenetic protein-2/7 bears a promising application potential to significantly promote bone regeneration and implant osteointegration for the patients with hypervitaminosis A and alcoholism. PMID:24205156

  19. Increased bone morphogenetic protein signaling contributes to age-related declines in neurogenesis and cognition.

    PubMed

    Meyers, Emily A; Gobeske, Kevin T; Bond, Allison M; Jarrett, Jennifer C; Peng, Chian-Yu; Kessler, John A

    2016-02-01

    Aging is associated with decreased neurogenesis in the hippocampus and diminished hippocampus-dependent cognitive functions. Expression of bone morphogenetic protein 4 (BMP4) increases with age by more than 10-fold in the mouse dentate gyrus while levels of the BMP inhibitor, noggin, decrease. This results in a profound 30-fold increase in phosphorylated-SMAD1/5/8, the effector of canonical BMP signaling. Just as observed in mice, a profound increase in expression of BMP4 is observed in the dentate gyrus of humans with no known cognitive abnormalities. Inhibition of BMP signaling either by overexpression of noggin or transgenic manipulation not only increases neurogenesis in aging mice, but remarkably, is associated with a rescue of cognitive deficits to levels comparable to young mice. Additive benefits are observed when combining inhibition of BMP signaling and environmental enrichment. These findings indicate that increased BMP signaling contributes significantly to impairments in neurogenesis and to cognitive decline associated with aging, and identify this pathway as a potential druggable target for reversing age-related changes in cognition. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Recombinant human bone morphogenetic protein 2 in augmentation procedures: case reports.

    PubMed

    Luiz, Jaques; Padovan, Luis Eduardo Marques; Claudino, Marcela

    2014-01-01

    To successfully rehabilitate edentulous patients using endosseous implants, there must be enough available bone. Several techniques have been proposed for augmentation of sites with insufficient bone volume. Although autogenous bone has long been considered the gold standard for such procedures, the limited availability of graft material and a high morbidity rate are potential disadvantages of this type of graft. An alternative is to use recombinant human bone morphogenetic protein 2 (rhBMP-2), which is able to support bone regeneration in the oral environment. These cases demonstrate the applicability of rhBMP-2 in maxillary sinus elevation and augmentation procedures in the maxilla to enable dental implant placement. The use of rhBMP-2 in alveolar augmentation procedures had several clinical benefits for these patients.

  1. Pharmacological activation of aldehyde dehydrogenase 2 promotes osteoblast differentiation via bone morphogenetic protein-2 and induces bone anabolic effect

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mittal, Monika; Pal, Subhashis; China, Shyamsundar

    Aldehyde dehydrogenases (ALDHs) are a family of enzymes involved in detoxifying aldehydes. Previously, we reported that an ALDH inhibitor, disulfiram caused bone loss in rats and among ALDHs, osteoblast expressed only ALDH2. Loss-of-function mutation in ALDH2 gene is reported to cause bone loss in humans which suggested its importance in skeletal homeostasis. We thus studied whether activating ALDH2 by N-(1, 3-benzodioxol-5-ylmethyl)-2, 6-dichlorobenzamide (alda-1) had osteogenic effect. We found that alda-1 increased and acetaldehyde decreased the differentiation of rat primary osteoblasts and expressions of ALDH2 and bone morphogenetic protein-2 (BMP-2). Silencing ALDH2 in osteoblasts abolished the alda-1 effects. Further, alda-1 attenuatedmore » the acetaldehyde-induced lipid-peroxidation and oxidative stress. BMP-2 is essential for bone regeneration and alda-1 increased its expression in osteoblasts. We then showed that alda-1 (40 mg/kg dose) augmented bone regeneration at the fracture site with concomitant increase in BMP-2 protein compared with control. The osteogenic dose (40 mg/kg) of alda-1 attained a bone marrow concentration that was stimulatory for osteoblast differentiation, suggesting that the tissue concentration of alda-1 matched its pharmacologic effect. In addition, alda-1 promoted modeling-directed bone growth and peak bone mass achievement, and increased bone mass in adult rats which reiterated its osteogenic effect. In osteopenic ovariectomized (OVX) rats, alda-1 reversed trabecular osteopenia with attendant increase in serum osteogenic marker (procollagen type I N-terminal peptide) and decrease in oxidative stress. Alda-1 has no effect on liver and kidney function. We conclude that activating ALDH2 by alda-1 had an osteoanabolic effect involving increased osteoblastic BMP-2 production and decreased OVX-induced oxidative stress. - Highlights: • Alda-1 induced osteoblast differentiation that involved upregulation of ALDH2 and BMP-2 • Alda-1 attenuated acetaldehyde-induced inhibition of osteoblast differentiation • Alda-1 enhanced bone regeneration at the fracture site and peak bone mass achievement • Alda-1 reversed trabecular osteopenia in OVX rats via an osteoanabolic mechanism.« less

  2. Bone morphogenetic proteins in musculoskeletal medicine.

    PubMed

    Giannoudis, Peter V; Einhorn, Thomas A

    2009-12-01

    Ongoing research at the molecular level has expanded our understanding of the physiological processes that regulate the complex phenomena of fracture healing and bone regeneration. A number of key molecules have been identified and shown to facilitate the progression of healing from one stage to another, leading to an uneventful outcome. Among these candidate molecules, bone morphogenetic proteins (BMPs) possess potent osteoinductive properties. They interact with osteoprogenitor cells, regulating both mitogenesis and differentiation potential. Since the discovery of BMPs, a number of experimental and clinical trials have supported their safety and efficacy of their use in therapy. Nonetheless, at times their efficacy falls short of expectations. Several factors have been identified as contributing to this result. It is anticipated that, as our knowledge expands and we understand better the complex pathways and cascades of molecular events attributable to BMPs, the application of these molecules in the clinical setting will continue to increase and to show more favourable outcomes. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. Synergistic Effects of Vascular Endothelial Growth Factor on Bone Morphogenetic Proteins Induced Bone Formation In Vivo: Influencing Factors and Future Research Directions

    PubMed Central

    Li, Bo; Wang, Hai; Qiu, Guixing; Su, Xinlin

    2016-01-01

    Vascular endothelial growth factor (VEGF) and bone morphogenetic proteins (BMPs), as key mediators in angiogenesis and osteogenesis, are used in a combined delivery manner as a novel strategy in bone tissue engineering. VEGF has the potential to enhance BMPs induced bone formation. Both gene delivery and material-based delivery systems were incorporated in previous studies to investigate the synergistic effects of VEGF and BMPs. However, their results were controversial due to variation of methods incorporated in different studies. Factors influencing the synergistic effects of VEGF on BMPs induced bone formation were identified and analyzed in this review to reduce confusion on this issue. The potential mechanisms and directions of future studies were also proposed here. Further investigating mechanisms of the synergistic effects and optimizing these influencing factors will help to generate more effective bone regeneration. PMID:28070506

  4. Gradual downhill running improves age-related skeletal muscle and bone weakness: implication of autophagy and bone morphogenetic proteins.

    PubMed

    Kim, Jeong-Seok; Lee, Young-Hee; Yi, Ho-Keun

    2016-12-01

    What is the central question of this study? Exercise training by running has an effect on age-related muscle and bone wasting that improves physical activity and quality of life in the elderly. However, the effect of downhill running on age-related muscle and bone wasting, and its mechanisms, are unclear. What is the main finding and its importance? Gradual downhill running can improve skeletal muscle growth and bone formation by enhancing autophagy and bone morphogenetic protein signalling in aged rats. Therefore, downhill running exercise might be a practical intervention to improve skeletal muscle and bone protection in the elderly. Recent evidence suggests that autophagy and the bone morphogenetic protein (BMP) signalling pathway regulate skeletal muscle growth and bone formation in aged rats. However, the effect of downhill running on muscle growth and bone formation is not well understood. Thus, we investigated the effect of downhill and uphill running on age-related muscle and bone weakness. Young and late middle-aged rats were randomly assigned to control groups (young, YC; and late middle-aged, LMC) and two types of running training groups (late middle-aged downhill, LMD; and late middle-aged uphill, LMU). Training was progressively carried out on a treadmill at a speed of 21 m min -1 with a slope of +10 deg for uphill training versus 16 m min -1 with a slope of -16 deg for downhill training, both for 60 min day -1 , 5 days week -1 for 8 weeks. Downhill and uphill training increased autophagy-related protein 5, microtubule-associated protein light chain, Beclin-1 and p62 proteins in aged rats. In addition, superoxide dismutase, haem oxygenase-1 and the BMP signalling pathway were elevated. Phosphorylation of mammalian target of rapamycin and myogenic differentiation were increased significantly in the LMD and LMU groups. Consequently, in the femur, BMP-2, BMP-7 and autophagy molecules were highly expressed in the LMD and LMU groups. These results suggest that both downhill and uphill training appear to have a positive effect on expression of autophagy molecules and BMPs. In particular, these physiological adaptations from gradual downhill exercise have an effect on bone morphological changes and muscle quality similar to gradual uphill training interventions in ageing. © 2016 The Authors. Experimental Physiology © 2016 The Physiological Society.

  5. The Effects of Tocotrienol and Lovastatin Co-Supplementation on Bone Dynamic Histomorphometry and Bone Morphogenetic Protein-2 Expression in Rats with Estrogen Deficiency.

    PubMed

    Chin, Kok-Yong; Abdul-Majeed, Saif; Mohamed, Norazlina; Ima-Nirwana, Soelaiman

    2017-02-15

    Both tocotrienol and statins are suppressors of the mevalonate pathway. Supplementation of tocotrienol among statin users could potentially protect them against osteoporosis. This study aimed to compare the effects of tocotrienol and lovastatin co-supplementation with individual treatments on bone dynamic histomorphometric indices and bone morphogenetic protein-2 (BMP-2) gene expression in ovariectomized rats. Forty-eight female Sprague-Dawley rats were randomized equally into six groups. The baseline was sacrificed upon receipt. All other groups were ovariectomized, except for the sham group. The ovariectomized groups were administered orally daily with (1) lovastatin 11 mg/kg/day alone; (2) tocotrienol derived from annatto bean (annatto tocotrienol) 60 mg/kg/day alone; (3) lovastatin 11 mg/kg/day, and annatto tocotrienol 60 mg/kg/day. The sham and ovariectomized control groups were treated with equal volume of vehicle. After eight weeks of treatment, the rats were sacrificed. Their bones were harvested for bone dynamic histomorphometry and BMP-2 gene expression. Rats supplemented with annatto tocotrienol and lovastatin concurrently demonstrated significantly lower single-labeled surface, but increased double-labeled surface, mineralizing surface, mineral apposition rate and bone formation rate compared to individual treatments ( p < 0.05). There was a parallel increase in BMP-2 gene expression in the rats receiving combined treatment ( p < 0.05). The combination of annatto tocotrienol and lovastatin exerted either additively or synergistically on selected bone parameters. In conclusion, tocotrienol can augment the bone formation and mineralization in rats receiving low-dose statins. Supplementation of tocotrienol in statin users can potentially protect them from osteoporosis.

  6. The Effects of Tocotrienol and Lovastatin Co-Supplementation on Bone Dynamic Histomorphometry and Bone Morphogenetic Protein-2 Expression in Rats with Estrogen Deficiency

    PubMed Central

    Chin, Kok-Yong; Abdul-Majeed, Saif; Mohamed, Norazlina; Ima-Nirwana, Soelaiman

    2017-01-01

    Both tocotrienol and statins are suppressors of the mevalonate pathway. Supplementation of tocotrienol among statin users could potentially protect them against osteoporosis. This study aimed to compare the effects of tocotrienol and lovastatin co-supplementation with individual treatments on bone dynamic histomorphometric indices and bone morphogenetic protein-2 (BMP-2) gene expression in ovariectomized rats. Forty-eight female Sprague-Dawley rats were randomized equally into six groups. The baseline was sacrificed upon receipt. All other groups were ovariectomized, except for the sham group. The ovariectomized groups were administered orally daily with (1) lovastatin 11 mg/kg/day alone; (2) tocotrienol derived from annatto bean (annatto tocotrienol) 60 mg/kg/day alone; (3) lovastatin 11 mg/kg/day, and annatto tocotrienol 60 mg/kg/day. The sham and ovariectomized control groups were treated with equal volume of vehicle. After eight weeks of treatment, the rats were sacrificed. Their bones were harvested for bone dynamic histomorphometry and BMP-2 gene expression. Rats supplemented with annatto tocotrienol and lovastatin concurrently demonstrated significantly lower single-labeled surface, but increased double-labeled surface, mineralizing surface, mineral apposition rate and bone formation rate compared to individual treatments (p < 0.05). There was a parallel increase in BMP-2 gene expression in the rats receiving combined treatment (p < 0.05). The combination of annatto tocotrienol and lovastatin exerted either additively or synergistically on selected bone parameters. In conclusion, tocotrienol can augment the bone formation and mineralization in rats receiving low-dose statins. Supplementation of tocotrienol in statin users can potentially protect them from osteoporosis. PMID:28212283

  7. Dexamethasone Enhances Osteogenic Differentiation of Bone Marrow- and Muscle-Derived Stromal Cells and Augments Ectopic Bone Formation Induced by Bone Morphogenetic Protein-2

    PubMed Central

    Yuasa, Masato; Yamada, Tsuyoshi; Taniyama, Takashi; Masaoka, Tomokazu; Xuetao, Wei; Yoshii, Toshitaka; Horie, Masaki; Yasuda, Hiroaki; Uemura, Toshimasa; Okawa, Atsushi; Sotome, Shinichi

    2015-01-01

    We evaluated whether dexamethasone augments the osteogenic capability of bone marrow-derived stromal cells (BMSCs) and muscle tissue-derived stromal cells (MuSCs), both of which are thought to contribute to ectopic bone formation induced by bone morphogenetic protein-2 (BMP-2), and determined the underlying mechanisms. Rat BMSCs and MuSCs were cultured in growth media with or without 10-7 M dexamethasone and then differentiated under osteogenic conditions with dexamethasone and BMP-2. The effects of dexamethasone on cell proliferation and osteogenic differentiation, and also on ectopic bone formation induced by BMP-2, were analyzed. Dexamethasone affected not only the proliferation rate but also the subpopulation composition of BMSCs and MuSCs, and subsequently augmented their osteogenic capacity during osteogenic differentiation. During osteogenic induction by BMP-2, dexamethasone also markedly affected cell proliferation in both BMSCs and MuSCs. In an in vivo ectopic bone formation model, bone formation in muscle-implanted scaffolds containing dexamethasone and BMP-2 was more than two fold higher than that in scaffolds containing BMP-2 alone. Our results suggest that dexamethasone potently enhances the osteogenic capability of BMP-2 and may thus decrease the quantity of BMP-2 required for clinical application, thereby reducing the complications caused by excessive doses of BMP-2. Highlights: 1. Dexamethasone induced selective proliferation of bone marrow- and muscle-derived cells with higher differentiation potential. 2. Dexamethasone enhanced the osteogenic capability of bone marrow- and muscle-derived cells by altering the subpopulation composition. 3. Dexamethasone augmented ectopic bone formation induced by bone morphogenetic protein-2. PMID:25659106

  8. Downregulation of bone morphogenetic protein receptor 2 promotes the development of neuroblastoma.

    PubMed

    Cui, Ximao; Yang, Yili; Jia, Deshui; Jing, Ying; Zhang, Shouhua; Zheng, Shan; Cui, Long; Dong, Rui; Dong, Kuiran

    2017-01-29

    Neuroblastoma (NB) is the most common extracranial solid tumor of childhood. In this study, we examined the expression of bone morphogenetic protein receptor 2 (BMPR2) in primary NB and adjacent non-tumor samples (adrenal gland). BMPR2 expression was significantly downregulated in NB tissues, particularly in high-grade NB, and was inversely related to the expression of the NB differentiation markers ferritin and enolase. The significance of the downregulation was further explored in cultured NB cells. While enforced expression of BMPR2 decreased cell proliferation and colony-forming activity, shRNA-mediated knockdown of BMPR2 led to increased cell growth and clonogenicity. In mice, NB cells harboring BMPR2 shRNA showed significantly increased tumorigenicity compared with control cells. We also performed a retrospective analysis of NB patients and identified a significant positive correlation between tumor BMPR2 expression and overall survival. These findings suggest that BMPR2 may play an important role in the development of NB. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Role of bone morphogenetic protein-7 in renal fibrosis

    PubMed Central

    Li, Rui Xi; Yiu, Wai Han; Tang, Sydney C. W.

    2015-01-01

    Renal fibrosis is final common pathway of end stage renal disease. Irrespective of the primary cause, renal fibrogenesis is a dynamic process which involves a large network of cellular and molecular interaction, including pro-inflammatory cell infiltration and activation, matrix-producing cell accumulation and activation, and secretion of profibrogenic factors that modulate extracellular matrix (ECM) formation and cell-cell interaction. Bone morphogenetic protein-7 is a protein of the TGF-β super family and increasingly regarded as a counteracting molecule against TGF-β. A large variety of evidence shows an anti-fibrotic role of BMP-7 in chronic kidney disease, and this effect is largely mediated via counterbalancing the profibrotic effect of TGF-β. Besides, BMP-7 reduced ECM formation by inactivating matrix-producing cells and promoting mesenchymal-to-epithelial transition (MET). BMP-7 also increased ECM degradation. Despite these observations, the anti-fibrotic effect of BMP-7 is still controversial such that fine regulation of BMP-7 expression in vivo might be a great challenge for its ultimate clinical application. PMID:25954203

  10. Increased Retinal Expression of the Pro-Angiogenic Receptor GPR91 via BMP6 in a Mouse Model of Juvenile Hemochromatosis

    PubMed Central

    Arjunan, Pachiappan; Gnanaprakasam, Jaya P.; Ananth, Sudha; Romej, Michelle A.; Rajalakshmi, Veeranan-Karmegam; Prasad, Puttur D.; Martin, Pamela M.; Gurusamy, Mariappan; Thangaraju, Muthusamy; Bhutia, Yangzom D.; Ganapathy, Vadivel

    2016-01-01

    Purpose Hemochromatosis, an iron-overload disease, occurs as adult and juvenile types. Mutations in hemojuvelin (HJV), an iron-regulatory protein and a bone morphogenetic protein (BMP) coreceptor, underlie most of the juvenile type. Hjv−/− mice accumulate excess iron in retina and exhibit aberrant vascularization and angiomas. A succinate receptor, GPR91, is pro-angiogenic in retina. We hypothesized that Hjv−/− retinas have increased BMP signaling and increased GPR91 expression as the basis of angiomas. Methods Expression of GPR91 was examined by qPCR, immunofluorescence, and Western blot in wild-type and Hjv−/− mouse retinas and pRPE cells. Influence of excess iron and BMP6 on GPR91 expression was investigated in ARPE-19 cells, and wild-type and Hjv−/− pRPE cells. Succinate was used to activate GPR91 and determine the effects of GPR91 signaling on VEGF expression. Signaling of BMP6 was studied by the expression of Smad1/5/8 and pSmad4, and the BMP-target gene Id1. The interaction of pSmad4 with GPR91 promoter was studied by ChIP. Results Expression of GPR91 was higher in Hjv−/− retinas and RPE than in wild-type counterparts. Unexpectedly, BMP signaling was increased, not decreased, in Hjv−/− retinas and RPE. Bone morphogenetic protein 6 induced GPR91 in RPE, suggesting that increased BMP signaling in Hjv−/− retinas was likely responsible for GPR91 upregulation. Exposure of RPE to excess iron and succinate as well as BMP6 and succinate increased VEGF expression. Bone morphogenetic protein 6 promoted the interaction of pSmad4 with GPR91 promoter in RPE. Conclusions G-protein-coupled receptor 91 is a BMP6 target and Hjv deletion enhances BMP signaling in retina, thus underscoring a role for excess iron and hemochromatosis in abnormal retinal vascularization. PMID:27046124

  11. Increased Retinal Expression of the Pro-Angiogenic Receptor GPR91 via BMP6 in a Mouse Model of Juvenile Hemochromatosis.

    PubMed

    Arjunan, Pachiappan; Gnanaprakasam, Jaya P; Ananth, Sudha; Romej, Michelle A; Rajalakshmi, Veeranan-Karmegam; Prasad, Puttur D; Martin, Pamela M; Gurusamy, Mariappan; Thangaraju, Muthusamy; Bhutia, Yangzom D; Ganapathy, Vadivel

    2016-04-01

    Hemochromatosis, an iron-overload disease, occurs as adult and juvenile types. Mutations in hemojuvelin (HJV), an iron-regulatory protein and a bone morphogenetic protein (BMP) coreceptor, underlie most of the juvenile type. Hjv(-/-) mice accumulate excess iron in retina and exhibit aberrant vascularization and angiomas. A succinate receptor, GPR91, is pro-angiogenic in retina. We hypothesized that Hjv(-/-) retinas have increased BMP signaling and increased GPR91 expression as the basis of angiomas. Expression of GPR91 was examined by qPCR, immunofluorescence, and Western blot in wild-type and Hjv(-/-) mouse retinas and pRPE cells. Influence of excess iron and BMP6 on GPR91 expression was investigated in ARPE-19 cells, and wild-type and Hjv(-/-) pRPE cells. Succinate was used to activate GPR91 and determine the effects of GPR91 signaling on VEGF expression. Signaling of BMP6 was studied by the expression of Smad1/5/8 and pSmad4, and the BMP-target gene Id1. The interaction of pSmad4 with GPR91 promoter was studied by ChIP. Expression of GPR91 was higher in Hjv(-/-) retinas and RPE than in wild-type counterparts. Unexpectedly, BMP signaling was increased, not decreased, in Hjv(-/-) retinas and RPE. Bone morphogenetic protein 6 induced GPR91 in RPE, suggesting that increased BMP signaling in Hjv(-/-) retinas was likely responsible for GPR91 upregulation. Exposure of RPE to excess iron and succinate as well as BMP6 and succinate increased VEGF expression. Bone morphogenetic protein 6 promoted the interaction of pSmad4 with GPR91 promoter in RPE. G-protein-coupled receptor 91 is a BMP6 target and Hjv deletion enhances BMP signaling in retina, thus underscoring a role for excess iron and hemochromatosis in abnormal retinal vascularization.

  12. Maxillary anterior ridge augmentation with recombinant human bone morphogenetic protein 2.

    PubMed

    Edmunds, Ryan K; Mealey, Brian L; Mills, Michael P; Thoma, Daniel S; Schoolfield, John; Cochran, David L; Mellonig, Jim

    2014-01-01

    No human studies exist on the use of recombinant human bone morphogenetic protein 2 (rhBMP-2) on an absorbable collagen sponge (ACS) as a sole graft material for lateral ridge augmentation in large ridge defect sites. This series evaluates the treatment outcome of maxillary anterior lateral ridge augmentation with rhBMP-2/ACS. Twenty patients were treated with rhBMP-2/ACS and fixation screws for space maintenance. Cone beam volumetric tomography measurements were used to determine gain in ridge width, and a bone core biopsy was obtained. The mean horizontal ridge gain was 1.2 mm across sites, and every site gained width.

  13. Treatment of AVN using the induction chamber technique and a biological-based approach: indications and clinical results.

    PubMed

    Calori, G M; Mazza, E; Colombo, M; Mazzola, S; Mineo, G V; Giannoudis, P V

    2014-02-01

    To determine the efficacy of core decompression (CD) technique combined with recombinant morphogenetic proteins, autologous mesenchymal stem cells (MSCs) and xenograft bone substitute into the necrotic lesion of the femoral head on clinical symptoms and on the progression of osteonecrosis of the femoral head. A total of 38 patients (40 hips) with early stage osteonecrosis of the femoral head were studied over a 4-year period. CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute was associated with a significant reduction in both pain and joint symptoms and reduced the incidence of fractural stages. At 36 months, 33 patients achieved clinical and radiographic healing. This long-term follow-up study confirmed that CD technique combined with recombinant morphogenetic proteins, autologous MSCs and xenograft bone substitute may be an effective treatment for patients with early stage osteonecrosis of the femoral head. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Polydopamine mediated assembly of hydroxyapatite nanoparticles and bone morphogenetic protein-2 on magnesium alloys for enhanced corrosion resistance and bone regeneration.

    PubMed

    Jiang, Yanan; Wang, Bi; Jia, Zhanrong; Lu, Xiong; Fang, Liming; Wang, Kefeng; Ren, Fuzeng

    2017-10-01

    Magnesium alloys have the great potential to be used as orthopedic implants due to their biodegradability and mechanical resemblance to human cortical bone. However, the rapid degradation in physiological environment with the evolution of hydrogen gas release hinders their clinical applications. In this study, we developed a novel functional and biocompatible coating strategy through polydopamine mediated assembly of hydroxyapatite nanoparticles and growth factor, bone morphogenetic protein-2 (BMP-2), onto the surface of AZ31 Mg alloys. Such functional coating has strong bonding with the substrate and can increase surface hydrophilicity of magnesium alloys. In vitro electrochemical corrosion and hydrogen evolution tests demonstrate that the coating can significantly enhance the corrosion resistance and therefore slow down the degradation of AZ31 Mg alloys. In vitro cell culture reveals that immobilization of HA nanoparticles and BMP-2 can obviously promote cell adhesion and proliferation. Furthermore, in vivo implantation tests indicate that with the synergistic effects of HA nanoparticles and BMP-2, the coating does not cause obvious inflammatory response and can significantly reduce the biodegradation rate of the magnesium alloys and induce the new bone formation adjacent to the implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2750-2761, 2017. © 2017 Wiley Periodicals, Inc.

  15. LIM mineralization protein-1 potentiates bone morphogenetic protein responsiveness via a novel interaction with Smurf1 resulting in decreased ubiquitination of Smads.

    PubMed

    Sangadala, Sreedhara; Boden, Scott D; Viggeswarapu, Manjula; Liu, Yunshan; Titus, Louisa

    2006-06-23

    Development and repair of the skeletal system and other organs is highly dependent on precise regulation of bone morphogenetic proteins (BMPs), their receptors, and their intracellular signaling proteins known as Smads. The use of BMPs clinically to induce bone formation has been limited in part by the requirement of much higher doses of recombinant proteins in primates than were needed in cell culture or rodents. Therefore, control of cellular responsiveness to BMPs is now a critical area that is poorly understood. We determined that LMP-1, a LIM domain protein capable of inducing de novo bone formation, interacts with Smurf1 (Smad ubiquitin regulatory factor 1) and prevents ubiquitination of Smads. In the region of LMP responsible for bone formation, there is a motif that directly interacts with the Smurf1 WW2 domain and can effectively compete with Smad1 and Smad5 for binding. We have shown that small peptides containing this motif can mimic the ability to block Smurf1 from binding Smads. This novel interaction of LMP-1 with the WW2 domain of Smurf1 to block Smad binding results in increased cellular responsiveness to exogenous BMP and demonstrates a novel regulatory mechanism for the BMP signaling pathway.

  16. An in vitro study of fibrin sealant as a carrier system for recombinant human bone morphogenetic protein (rhBMP)-9 for bone tissue engineering.

    PubMed

    Fujioka-Kobayashi, Masako; Mottini, Matthias; Kobayashi, Eizaburo; Zhang, Yufeng; Schaller, Benoit; Miron, Richard J

    2017-01-01

    In the craniofacial bone field, fibrin sealants are used as coagulant and adhesive tools to stabilize grafts during surgery. Despite this, their exact role in osteogenesis is poorly characterized. In the present study, we aimed to characterize the osteogenic potential of TISSEEL fibrin sealant and used its technology to incorporate growth factors within its matrix. We focused on recombinant human bone morphogenetic protein (rhBMP)-9, which has previously been characterized as one of the strongest osteogenetic inducers in the BMP family. TISSEEL displayed an excellent ability to retain rhBMP9, which was gradually released over a 10-day period. Although TISSEEL decreased bone stromal ST2 cell attachment at 8 h, it displayed normal cell proliferation at 1, 3, and 5 days when compared to tissue culture plastic. Interestingly, TISSEEL had little influence on osteoblast differentiation; however its combination with rhBMP9 significantly increased ALP activity at 7 days, Alizarin Red staining at 14 days, and mRNA levels of osteoblast differentiation markers ALP, bone sialoprotein, and osteocalcin. In summary, although fibrin sealants were shown to have little influence on osteogenesis, their combination with bone-inducing growth factors such as rhBMP9 may serve as an attractive carrier/scaffold for future bone regenerative strategies. Future animal studies are now necessary. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  17. Radiographic and Histologic Evaluation of a Bone Void that Formed After Recombinant Human Bone Morphogenetic Protein-2-Mediated Sinus Graft Augmentation: A Case Report.

    PubMed

    Kang, Hyun-Joo; Jun, Choong-Man; Yun, Jeong-Ho

    2016-01-01

    In the present case report, the authors describe radiographic and histologic observations of a bone void that formed after a sinus augmentation using a graft material that contained recombinant human bone morphogenetic protein-2 (rhBMP-2) and discuss clinical and histologic implications of their findings. Sinus augmentation was performed using a graft material comprising 1 g of hydroxyapatite/β-tricalcium phosphate, which contained 1 mg of rhBMP-2. Radiographic evaluation was conducted with panoramic radiographs and computed tomography images of the augmented maxillary sinus, which were analyzed using a three-dimensional image-reconstruction program. Histologic evaluation was also performed on a biopsy specimen obtained 6 months after the sinus augmentation. The total augmented volume increased from 1,582.2 mm(3) immediately after the sinus augmentation to 3,344.9 mm3 at 6 months after the augmentation because of the formation of a bone void. Twenty-six months after the sinus augmentation, the bone void remained but had reduced in volume, with the total augmented volume reduced to 2,551.7 mm(3). Histologically, new bone was observed to be in contact with the grafted particles, and a fatty marrow-like tissue was present in the area of the bone void. This case report shows that the bone void that had formed after sinus augmentation resolved over time and seemed to be partially replaced with new bone. Furthermore, none of the implants failed, and clinical adverse events were not observed during the follow-up period.

  18. A high concentration of recombinant human bone morphogenetic protein-2 induces low-efficacy bone regeneration in sinus augmentation: a histomorphometric analysis in rabbits.

    PubMed

    Hong, Ji-Youn; Kim, Min-Soo; Lim, Hyun-Chang; Lee, Jung-Seok; Choi, Seong-Ho; Jung, Ui-Won

    2016-12-01

    The aim of the study was to elucidate the efficacy of bone regeneration at the early stage of healing in rabbit sinuses grafted with a biphasic calcium phosphate (BCP) carrier soaked in a high concentration of recombinant human bone morphogenetic protein-2 (rhBMP-2). Both maxillary sinuses of eight male rabbits were used. The sinus on one side (assigned randomly) was grafted with BCP loaded with rhBMP-2 (1.5 mg/ml; test group) using a soaking method, while the other was grafted with saline-soaked BCP (control group). After a 2-week healing period, the sinuses were analyzed by micro-computed tomography and histomorphometry. The total augmented area and soft tissue space were significantly larger in the test group than in the control group, whereas the opposite was true for the area of residual material and newly formed bone. Most of the new bone in the test group was localized to the Schneiderian membrane (SM), while very little bone formation was observed in the window and center regions of the sinus. New bone was distributed evenly in the control group sinuses. Within the limitations of this study, it appeared that application of a high concentration of rhBMP-2 soaked onto a BCP carrier inhibited bone regeneration from the pristine bone and increased soft tissue swelling and inflammatory response at the early healing stage of sinus augmentation, although osteoinductive potential was found along the SM. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Acceleration of Alveolar Ridge Augmentation Using a Low Dose of Recombinant Human Bone Morphogenetic Protein-2 Loaded on a Resorbable Bioactive Ceramic.

    PubMed

    Fahmy, Rania A; Mahmoud, Naguiba; Soliman, Samia; Nouh, Samir R; Cunningham, Larry; El-Ghannam, Ahmed

    2015-12-01

    The aim of the present study was to evaluate the effect of a porous silica-calcium phosphate composite (SCPC50) loaded with and without recombinant human bone morphogenetic protein-2 (rhBMP-2) on alveolar ridge augmentation in saddle-type defects. Micro-granules of SCPC50 resorbable bioactive ceramic were coated with rhBMP-2 10 mg and then implanted into a saddle-type defect (12 × 7 mm) in a dog mandible and covered with a collagen membrane. Control groups included defects grafted with SCPC50 granules without rhBMP-2 and un-grafted defects. Bone healing was evaluated at 8 and 16 weeks using histologic and histomorphometric techniques. The increase in bone height and total defect fill were assessed for each specimen using the ImageJ 1.46 program. The release kinetics of rhBMP-2 was determined in vitro. The height of the bone in the grafted defects and the total defect fill were statistically analyzed. SCPC50 enhanced alveolar ridge augmentation as indicated by the increased vertical bone height, bone surface area, and bone volume after 16 weeks. SCPC50-rhBMP-2 provided a sustained release profile of a low effective dose (BMP-2 4.6 ± 1.34 pg/mL per hour) during the 1- to 21-day period. The slow rate of release of rhBMP-2 from SCPC50 accelerated synchronized complete bone regeneration and graft material resorption in 8 weeks. Successful rapid reconstruction of the alveolar ridge by SCPC50 and SCPC50-rhBMP-2 occurred without any adverse excessive bone formation, inflammation, or fluid-filled voids. Results of this study suggest that SCPC50 is an effective graft material to preserve the alveolar ridge after tooth extraction. Coating SCPC50-rhBMP-2 further accelerated bone regeneration and a considerable increase in vertical bone height. These findings make SCPC50 the primary choice as a carrier for rhBMP-2. SCPC50-rhBMP-2 can serve as an alternative to autologous bone grafting. Published by Elsevier Inc.

  20. Turning Bone Morphogenetic Protein 2 (BMP2) On and Off in Mesenchymal Cells†

    PubMed Central

    Rogers, Melissa B.; Shah, Tapan A.; Shaikh, Nadia N.

    2016-01-01

    The concentration, location, and timing of bone morphogenetic protein 2 (BMP2, HGNC:1069, GeneID: 650) gene expression must be precisely regulated. Abnormal BMP2 levels cause congenital anomalies and diseases involving the mesenchymal cells that differentiate into muscle, fat, cartilage, and bone. The molecules and conditions that influence BMP2 synthesis are diverse. Understandably, complex mechanisms control Bmp2 gene expression. This review includes a compilation of agents and conditions that can induce Bmp2. The currently known trans-regulatory factors and cis-regulatory elements that modulate Bmp2 expression are summarized and discussed. This article is protected by copyright. All rights reserved PMID:25776852

  1. Segmental Bone Regeneration Using a Load Bearing Biodegradable Carrier of Bone Morphogenetic Protein-2

    PubMed Central

    Chu, Tien-Min G.; Warden, Stuart J.; Turner, Charles H.; Stewart, Rena L.

    2006-01-01

    Segmental defect regeneration has been a clinical challenge. Current tissue engineering approach using porous biodegradable scaffolds to delivery osteogenic cells and growth factors demonstrated success in facilitating bone regeneration in these cases. However, due to the lack of mechanical property, the porous scaffolds were evaluated in non-load bearing area or were stabilized with stress-shielding devices (bone plate or external fixation). In this paper, we tested a scaffold that does not require a bone plate because it has sufficient biomechanical strength. The tube-shaped scaffolds were manufactured from poly(propylene) fumarate/tricalcium phosphate (PPF/TCP) composites. Dicalcium phosphate dehydrate (DCPD) were used as bone morphogenetic protein -2 (BMP-2) carrier. Twenty two scaffolds were implanted in 5 mm segmental defects in rat femurs stabilized with k-wire for 6 and 15 weeks with and without 10 μg of rhBMP-2. Bridging of the segmental defect was evaluated first radiographically and was confirmed by histology and micro- computer tomography (μ-CT) imaging. The scaffolds in the BMP group maintained the bone length throughout the duration of the study and allow for bridging. The scaffolds in the control group failed to induce bridging and collapsed at 15 weeks. Peripheral computed tomography (pQCT) showed that BMP-2 does not increase the bone mineral density in the callus. Finally, the scaffold in BMP group was found to restore the mechanical property of the rat femur after 15 weeks. Our results demonstrated that the load-bearing BMP-2 scaffold can maintain bone length and allow successfully regeneration in segmental defects. PMID:16996588

  2. Bone morphogenetic protein 2 and decorin expression in old fracture fragments and surrounding tissues.

    PubMed

    Han, X G; Wang, D K; Gao, F; Liu, R H; Bi, Z G

    2015-09-21

    Bone morphogenetic protein 2 (BMP-2) can promote fracture healing. Although the complex role BMP-2 in bone formation is increasingly understood, the role of endogenous BMP-2 in nonunion remains unclear. Decorin (DCN) can promote the formation of bone matrix and calcium deposition to control bone morphogenesis. In this study, tissue composition and expression of BMP-2 and DCN were detected in different parts of old fracture zones to explore inherent anti-fibrotic ability and osteogenesis. Twenty-three patients were selected, including eight cases of delayed union and 15 cases of nonunion. Average duration of delayed union or nonunion was 15 months. Fracture fragments and surrounding tissues, including bone grafts, marrow cavity contents, and sticking scars, were categorically sampled during surgery. Through observation and histological testing, component comparisons were made between fracture fragments and surrounding tissue. The expression levels of DCN and BMP-2 in different tissues were detected by immunohistochemical staining and real-time polymerase chain reaction. The expression of DCN and BMP- 2 in different parts of the nonunion area showed that, compared with bone graft and marrow cavity contents, sticking scars had the highest expression of BMP-2. Compared with the marrow cavity contents and sticking scars, bone grafts had the highest expression of DCN. The low antifibrotic and osteogenic activity of the nonunion area was associated with non-co-expression of BMP-2 and DCN. Therefore, the co-injection of osteogenic factor BMP and DCN into the nonunion area can improve the induction of bone formation and enhance the conversion of the old scar, thereby achieving better nonunion treatment.

  3. Open tibial fractures grade IIIC treated successfully with external fixation, negative-pressure wound therapy and recombinant human bone morphogenetic protein 7.

    PubMed

    Babiak, Ireneusz

    2014-10-01

    The aim of the therapy in open tibial fractures grade III was to cover the bone with soft tissue and achieve healed fracture without persistent infection. Open tibial fractures grade IIIC with massive soft tissue damage require combined orthopaedic, vascular and plastic-reconstructive procedures. Negative-pressure wound therapy (NPWT), used in two consecutive cases with open fracture grade IIIC of the tibia diaphysis, healed extensive soft tissue defect with exposure of the bone. NPWT eventually allowed for wound closure by split skin graft within 21-25 days. Ilizarov external fixator combined with application of recombinant human bone morphogenetic protein-7 at the site of delayed union enhanced definitive bone healing within 16-18 months. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  4. Bone morphogenetic protein 7 (BMP-7) influences tendon-bone integration in vitro.

    PubMed

    Schwarting, Tim; Lechler, Philipp; Struewer, Johannes; Ambrock, Marius; Frangen, Thomas Manfred; Ruchholtz, Steffen; Ziring, Ewgeni; Frink, Michael

    2015-01-01

    Successful graft ingrowth following reconstruction of the anterior cruciate ligament is governed by complex biological processes at the tendon-bone interface. The aim of this study was to investigate in an in vitro study the effects of bone morphogenetic protein 7 (BMP-7) on tendon-bone integration. To study the biological effects of BMP-7 on the process of tendon-bone-integration, two independent in vitro models were used. The first model involved the mono- and coculture of bovine tendon specimens and primary bovine osteoblasts with and without BMP-7 exposure. The second model comprised the mono- and coculture of primary bovine osteoblasts and fibroblasts. Alkaline phosphatase (ALP), lactate dehydrogenase (LDH), lactate and osteocalcin (OCN) were analyzed by ELISA. Histological analysis and electron microscopy of the tendon specimens were performed. In both models, positive effects of BMP-7 on ALP enzyme activity were observed (p<0.001). Additionally, similar results were noted for LDH activity and lactate concentration. BMP-7 stimulation led to a significant increase in OCN expression. Whereas the effects of BMP-7 on tendon monoculture peaked during an early phase of the experiment (p<0.001), the cocultures showed a maximal increase during the later stages (p<0.001). The histological analysis showed a stimulating effect of BMP-7 on extracellular matrix formation. Organized ossification zones and calcium carbonate-like structures were only observed in the BMP-stimulated cell cultures. This study showed the positive effects of BMP-7 on the biological process of tendon-bone integration in vitro. Histological signs of improved mineralization were paralleled by increased rates of osteoblast-specific protein levels in primary bovine osteoblasts and fibroblasts. Our findings indicated a role for BMP-7 as an adjuvant therapeutic agent in the treatment of ligamentous injuries, and they emphasized the importance of the transdifferentiation process of tendinous fibroblasts at the tendon-bone interface.

  5. Effects of laser photherapy on bone defects grafted with mineral trioxide aggregate, bone morphogenetic proteins, and guided bone regeneration: a Raman spectroscopic study.

    PubMed

    Pinheiro, Antonio L B; Aciole, Gilberth T S; Cangussú, Maria Cristina T; Pacheco, Marcos T T; Silveira, Landulfo

    2010-12-15

    We have used Raman analysis to assess bone healing on different models. Benefits on the isolated or combined use of mineral trioxide aggregate, bone morphogenetic proteins, guided bone regeneration and laser on bone repair have been reported, but not their combination. We studied peaks of hydroxyapatite and CH groups on defects grafted with MTA, treated or not with laser, BMPs, and GBR. Ninety rats were divided in 10 groups each, subdivided into three subgroups. Laser (λ850 nm) was applied at every other day for 2 weeks. Raman readings were taken at the surface of the defect. Statistical analysis (CHA) showed significant differences between all groups (p = 0.001) and between Group II and all other (p < 0.001), but not with Group X (p = 0.09). At day 21 differences were seen between all groups (p = 0.031) and between Groups VIII and X when compared with Groups VI (p = 0.03), V (p < 0.001), IV (p < 0.001), and IX (p = 0.04). At the end of the experimental period no significant differences were seen. On regards CH, significant differences were seen at the 15(th) day (p = 0.002) and between Group II and all other groups (p < 0.0001) but not with control. Advanced maturation on irradiated bone is because of increased secretion of calcium hydroxyapatite (CHA) that is indicative of greater calcification and resistance of the bone. We conclude that the association of the MTA with laser phototherapy (LPT) and/or not with GBR resulted in a better bone repair. The use of the MTA associated to IR LPT resulted in a more advanced and quality bone repair. Copyright © 2010 Wiley Periodicals, Inc.

  6. Binding of integrin α1 to bone morphogenetic protein receptor IA suggests a novel role of integrin α1β1 in bone morphogenetic protein 2 signalling.

    PubMed

    Zu, Yan; Liang, Xudong; Du, Jing; Zhou, Shuai; Yang, Chun

    2015-11-05

    Here, we observed that integrin α1β1 and bone morphogenetic protein receptor (BMPR) IA formed a complex and co-localised in several cell types. However, the molecular interaction between these two molecules was not studied in detail to date and the role of the interaction in BMPR signalling remains unknown; thus, these were investigated here. In a steered molecular dynamics (SMD) simulation, the observed development of the rupture force related to the displacement between the A-domain of integrin α1 and the extracellular domain of BMPR IA indicated a strong molecular interaction within the integrin-BMPR complex. Analysis of the intermolecular forces revealed that hydrogen bonds, rather than salt bridges, are the major contributors to these intermolecular interactions. By using Enzyme-linked immunosorbent assay (ELISA) and co-immunoprecipitation (co-IP) experiments with site-directed mutants, we found that residues 85-89 in BMPR IA play the most important role for BMPR IA binding to integrin α1β1. These residues are the same as those responsible for bone morphogenetic protein 2 (BMP-2)/BMPR IA binding. In our experiments, we also found that the interference of integrin α1β1 up regulated the level of phosphorylated Smad1, 5, 8, which is the downstream of BMP/BMPR signalling. Therefore, our results suggest that integrin α1β1/BMPR IA may block BMP-2/BMPR IA complex information and interfere with the BMP-2 signalling pathway in cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Activin- and Nodal-related factors control antero-posterior patterning of the zebrafish embryo.

    PubMed

    Thisse, B; Wright, C V; Thisse, C

    2000-01-27

    Definition of cell fates along the dorso-ventral axis depends on an antagonistic relationship between ventralizing transforming growth factor-beta superfamily members, the bone morphogenetic proteins and factors secreted from the dorsal organizer, such as Noggin and Chordin. The extracellular binding of the last group to the bone morphogenetic proteins prevents them from activating their receptors, and the relative ventralizer:antagonist ratio is thought to specify different dorso-ventral cell fates. Here, by taking advantage of a non-genetic interference method using a specific competitive inhibitor, the Lefty-related gene product Antivin, we provide evidence that cell fate along the antero-posterior axis of the zebrafish embryo is controlled by the morphogenetic activity of another transforming growth factor-beta superfamily subgroup--the Activin and Nodal-related factors. Increasing antivin doses progressively deleted posterior fates within the ectoderm, eventually resulting in the removal of all fates except forebrain and eyes. In contrast, overexpression of activin or nodal-related factors converted ectoderm that was fated to be forebrain into more posterior ectodermal or mesendodermal fates. We propose that modulation of intercellular signalling by Antivin/Activin and Nodal-related factors provides a mechanism for the graded establishment of cell fates along the antero-posterior axis of the zebrafish embryo.

  8. The ventralizing activity of Radar, a maternally expressed bone morphogenetic protein, reveals complex bone morphogenetic protein interactions controlling dorso-ventral patterning in zebrafish.

    PubMed

    Goutel, C; Kishimoto, Y; Schulte-Merker, S; Rosa, F

    2000-12-01

    In Xenopus and zebrafish, BMP2, 4 and 7 have been implicated, after the onset of zygotic expression, in inducing and maintaining ventro-lateral cell fate during early development. We provide evidence here that a maternally expressed bone morphogenetic protein (BMP), Radar, may control early ventral specification in zebrafish. We show that Radar ventralizes zebrafish embryos and induces the early expression of bmp2b and bmp4. The analysis of Radar overexpression in both swirl/bmp2b mutants and embryos expressing truncated BMP receptors shows that Radar-induced ventralization is dependent on functional BMP2/4 pathways, and may initially rely on an Alk6-related signaling pathway. Finally, we show that while radar-injected swirl embryos still exhibit a strongly dorsalized phenotype, the overexpression of Radar into swirl/bmp2b mutant embryos restores ventral marker expression, including bmp4 expression. Our results suggest that a complex regulation of different BMP pathways controls dorso-ventral (DV) patterning from early cleavage stages until somitogenesis.

  9. Bone Morphogenetic Protein Usage in Anterior Lumbar Interbody Fusion: What Else Can Go Wrong?

    PubMed

    Elias, Elias; Nasser, Zeina; Winegan, Lona; Verla, Terence; Omeis, Ibrahim

    2018-03-01

    Bone morphogenetic protein (BMP) graft showed promising outcome during early phases of its use. However, unreported adverse events and off-label use shattered its safe profile and raised concerns regarding its indication. In 2008 the U.S. Food and Drug Administration prohibited its use in anterior cervical spine procedures due to the possibility of edema, hematoma, and need to intubate. At the molecular level, BMPs act as multifactorial growth factors playing a role in cartilage, heart, and bone formation. However, its unfavorable effect on bone overgrowth or heterotopic ossification post spine surgeries has been described. Reported cases in the literature were limited to epidural bone formation. We present a rare and interesting case of a 59-year-old female, in whom BMP caused intradural bone growth several years after an anterior lumbar interbody fusion surgery. Caution must be exercised while using BMPs because of inadvertent complications. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. The bone morphogenetic protein axis is a positive regulator of skeletal muscle mass

    PubMed Central

    Chen, Justin L.; Qian, Hongwei; Liu, Yingying; Bernardo, Bianca C.; Beyer, Claudia; Watt, Kevin I.; Thomson, Rachel E.; Connor, Timothy; Turner, Bradley J.; McMullen, Julie R.; Larsson, Lars; McGee, Sean L.; Harrison, Craig A.

    2013-01-01

    Although the canonical transforming growth factor β signaling pathway represses skeletal muscle growth and promotes muscle wasting, a role in muscle for the parallel bone morphogenetic protein (BMP) signaling pathway has not been defined. We report, for the first time, that the BMP pathway is a positive regulator of muscle mass. Increasing the expression of BMP7 or the activity of BMP receptors in muscles induced hypertrophy that was dependent on Smad1/5-mediated activation of mTOR signaling. In agreement, we observed that BMP signaling is augmented in models of muscle growth. Importantly, stimulation of BMP signaling is essential for conservation of muscle mass after disruption of the neuromuscular junction. Inhibiting the phosphorylation of Smad1/5 exacerbated denervation-induced muscle atrophy via an HDAC4-myogenin–dependent process, whereas increased BMP–Smad1/5 activity protected muscles from denervation-induced wasting. Our studies highlight a novel role for the BMP signaling pathway in promoting muscle growth and inhibiting muscle wasting, which may have significant implications for the development of therapeutics for neuromuscular disorders. PMID:24145169

  11. [Slow-release recombinant human bone morphogenetic protein-2 suppresses chromium wear particle-induced osteolysis in rats].

    PubMed

    Li, Gan; Li, Qi; Lin, Li-Jun; Duan, Xin; Zhang, Xi-Qi

    2012-03-01

    To observe the effect of a slow-release recombinant human bone morphogenetic protein-2 (rhBMP-2) formulation on the expressions of receptor activator of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) in a murine air pouch model of bone implantation. A cranial bone allograft was implanted in the air pouch induced on the back of the recipients. The rat models were then randomized into 5 groups, including a blank control group, chromium particle group, and 3 rhBMP-2 groups receiving 50, 100 or 200 µg/L slow-release rhBMP-2 in addition to chromium particles. Three weeks later, the expressions of RANKL and OPG in the air pouch was detected using Western blotting and RT-PCR, and the positively stained area for osteoclasts in the bone graft was determined with TRAP staining for drug effect assessment. RANKL and OPG expressions were found in the air pouches in all the 5 groups. RANKL and OPG protein and mRNA expressions, RANKL/OPG ratio and osteoclast staining area in the bone graft were the highest in chromium particle group (P<0.05), but were significantly decreased by treatment with the slow-release rhBMP-2 formulation (P<0.05); the measurements showed no significant differences between the blank control group and 200 µg/L rhBMP-2 group (P>0.05). Chromium particles can cause osteolysis by increasing the RANKL/OPG ratio in rats, and intervention with slow-release rhBMP-2 can significantly promote bone formation and suppress bone resorption by decreasing RANKL/OPG ratio.

  12. Effect of recombinant human bone morphogenetic protein-2 on bone regeneration and osseointegration of dental implants.

    PubMed

    Sykaras, N; Triplett, R G; Nunn, M E; Iacopino, A M; Opperman, L A

    2001-08-01

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) induced bone regeneration and osseointegration was evaluated in bony defects created within the hollow chamber of endosseous dental implants in 14 foxhound dogs. Bilateral extractions of mandibular premolars were performed and surgical implantation of 104 hollow cylinder implants followed after 8 weeks of healing. Experimental implants had their hollow chamber filled with 20 microg of rhBMP-2 delivered with a bovine collagen carrier, whereas the control implants had their apical chamber left empty. Dogs were followed for 2, 4, 8 and 12 weeks. Histomorphometric evaluation and immunohistochemical analysis were performed. Minimal bone was regenerated at 2 weeks for both groups. At 4 weeks, bone fill averaged 23.48% for the rhBMP-2 and 5.98% for the control group (P<0.05). At 8 weeks, mean bone fill was 20.94% and 7.75% for the rhBMP-2 and the controls, respectively (P<0.05). At 12 weeks, mean bone fill was 31.39% and 24.31% for the rhBMP-2 and control implants, respectively (P>0.05). Bone-implant contact (BIC) increased for both groups over time and at 8 weeks the rhBMP-2 BIC value was 18.65% and for the control 7.22% (P<0.05). At 12 weeks, the BIC was 43.78% and 21.05% for the rhBMP-2 and the control group, respectively (P<0.05). Immunohistochemical staining for type II collagen was positive only for parts of the collagen carrier and formation of cartilaginous intermediate was not observed in any of the specimens. The results suggest that, in confined defects adjacent to dental implants, rhBMP-2 can induce bone regeneration in close apposition to the implant surface.

  13. Effects of orthopedic implants with a polycaprolactone polymer coating containing bone morphogenetic protein-2 on osseointegration in bones of sheep.

    PubMed

    Niehaus, Andrew J; Anderson, David E; Samii, Valerie F; Weisbrode, Steven E; Johnson, Jed K; Noon, Mike S; Tomasko, David L; Lannutti, John J

    2009-11-01

    To determine elution characteristics of bone morphogenetic protein (BMP)-2 from a polycaprolactone coating applied to orthopedic implants and determine effects of this coating on osseointegration. 6 sheep. An in vitro study was conducted to determine BMP-2 elution from polycaprolactone-coated implants. An in vivo study was conducted to determine the effects on osseointegration when the polycaprolactone with BMP-2 coating was applied to bone screws. Osseointegration was assessed via radiography, measurement of peak removal torque and bone mineral density, and histomorphometric analysis. Physiologic response was assessed by measuring serum bone-specific alkaline phosphatase activity and uptake of bone markers. Mean +/- SD elution on day 1 of the in vitro study was 263 +/- 152 pg/d, which then maintained a plateau at 59.8 +/- 29.1 pg/d. Mean peak removal torque for screws coated with polycalprolactone and BMP-2 (0.91 +/- 0.65 dN x m) and screws coated with polycaprolactone alone (0.97 +/- 1.30 dN.m) did not differ significantly from that for the control screws (2.34 +/- 1.62 dN x m). Mean bone mineral densities were 0.535 +/- 0.060 g/cm(2), 0.596 +/- 0.093 g/cm(2), and 0.524 +/- 0.142 g/cm(2) for the polycaprolactone-BMP-2-coated, polycaprolactone-coated, and control screws, respectively, and did not differ significantly among groups. Histologically, bone was in closer apposition to the implant with the control screws than with either of the coated screws. BMP-2 within the polycaprolactone coating did not stimulate osteogenesis. The polycaprolactone coating appeared to cause a barrier effect that prevented formation of new bone. A longer period or use of another carrier polymer may result in increased osseointegration.

  14. A Comparative Analysis of Recombinant Human Bone Morphogenetic Protein-2 with a Demineralized Bone Matrix versus Iliac Crest Bone Graft for Secondary Alveolar Bone Grafts in Patients with Cleft Lip and Palate: Review of 501 Cases.

    PubMed

    Hammoudeh, Jeffrey A; Fahradyan, Artur; Gould, Daniel J; Liang, Fan; Imahiyerobo, Thomas; Urbinelli, Leo; Nguyen, JoAnna T; Magee, William; Yen, Stephen; Urata, Mark M

    2017-08-01

    Alveolar cleft reconstruction using iliac crest bone graft is considered standard of care for children with complete cleft lip and palate at the time of mixed dentition. Harvesting bone may result in donor-site morbidity and additional operating time and length of hospitalization. Recombinant human bone morphogenetic protein (rhBMP)-2 with a demineralized bone matrix is an alternative bone source for alveolar cleft reconstruction. The authors investigated the outcomes of rhBMP-2/demineralized bone matrix versus iliac crest bone graft for alveolar cleft reconstruction by reviewing postoperative surgical complications and cleft closure. A retrospective chart review was conducted for 258 rhBMP-2/demineralized bone matrix procedures (mean follow-up, 2.9 years) and 243 iliac crest bone graft procedures (mean follow-up, 4.1 years) on 414 patients over a 12-year period. The authors compared complications, canine eruption, and alveolar cleft closure between the two groups. In the rhBMP-2/demineralized bone matrix group, one patient required prolonged intubation because of intraoperative airway swelling not thought to be caused by rhBMP-2, 36 reported facial swelling and one required outpatient steroids as treatment, and 12 had dehiscence; however, half of these complications resolved without intervention. Twenty-three of the 228 rhBMP-2/demineralized bone matrix patients and 28 of the 242 iliac crest bone graft patients required repeated surgery for alveolar cleft repair. Findings for canine tooth eruption into the cleft site through the graft were similar between the groups. The rhBMP-2/demineralized bone matrix appears to be an acceptable alternative for alveolar cleft repair. The authors found no increase in serious adverse events with the use of this material. Local complications, such as swelling and minor wound dehiscence, predominantly improved without intervention. Therapeutic, III.

  15. Progenitor Cell Fate Decisions in Mammary Tumorigenesis

    DTIC Science & Technology

    2013-03-01

    31.8 NM_134032 Homeo box 82 Hoxb2 18.0 BC011063 HomeoboxAS Hoxa5 17.1 AW105779 Lactate dehydrogenase D Ldbd 14.6 AV367068 Desert hedgehog Dhh 13.8...Fgfrl 689 NM_009704 AmpbiJeplin Areg 663 AV304616 Sonic hedgehog Shh 44.6 NM_D10446 Forklad box A2 Foxa2 42.6 NM_007!’i54 Bone morphogenetic protein...111.5 AV304616 Sonic hedgehog Shb 104.9 NM....010446 Fo!thead box A2 Foxa2 81.7 NM_007SS4 Bone morphogenetic protein 4 Bmp4 69.4 NM_008010 Fibroblast

  16. Survey of the Effectiveness of Internet Information on Patient Education for Bone Morphogenetic Protein.

    PubMed

    Huang, Meng; Briceño, Valentina; Lam, Sandi K; Luerssen, Thomas G; Jea, Andrew

    2016-03-01

    In light of recent reports of potential short- and long-term complications of bone morphogenetic protein (BMP) and increasing "off-label" use among spine surgeons, we wished to analyze online information on BMP and its controversial uses, as patients frequently search the Internet for medical information, even though the quality and accuracy of available information are highly variable. Between December 2014 and January 2015, we conducted a Google search to identify the 50 most accessed websites providing BMP information using the search phrase "bone morphogenetic protein." Websites were classified based on authorship. Each website was examined for the provision of appropriate patient inclusion and exclusion criteria, surgical and nonsurgical treatment alternatives, purported benefits, disclosure of common and potential complications, peer-reviewed literature citations, and discussion of off-label use. Two percent of websites were authored by private medical groups, 2% by academic medical groups, 10% by insurance companies, 16% by biomedical industries, 4% by news sources, 0% by lawyers, and 66% by others. Sixty-two percent referenced peer-reviewed literature. Benefits and complications were reported in 44% and 26% of websites, respectively. Surgical and nonsurgical treatment alternatives were mentioned in 16% and 4% of websites, respectively. Discussion of off-label BMP use occurred in 18% of websites. Our study showed the ineffectiveness of the Internet in reporting quality information on BMP use. We found that websites authored by insurance companies provide an acceptable foundation for patient education. This, however, cannot replace the need for a thorough dialogue between doctor and patient about risks, benefits, and indications. Copyright © 2016. Published by Elsevier Inc.

  17. Local strategies to prevent and treat osteoporosis.

    PubMed

    Torstrick, F Brennan; Guldberg, Robert E

    2014-03-01

    Despite advances in systemic osteoporosis therapeutic outcomes, management of fragility fractures and implant fixation in osteoporotic bone remain difficult clinical challenges. Low initial bone density and a prolonged healing response can lead to fracture nonunion and aseptic implant loosening. Local treatment strategies could be used to prevent fracture, accelerate healing, and increase implant fixation by locally stimulating anabolic pathways or inhibiting catabolic pathways. Local strategies under investigation include direct drug release from injectable materials or implant surface coatings. Common locally delivered drugs include bisphosphonates, parathyroid hormone, and bone morphogenetic proteins, yet additional compounds targeting novel pathways in bone biology are also being actively explored. Mechanical stimulation via low intensity pulsed ultrasound, alone or in combination with drug therapy, may also prove effective to promote local bone healing and implant fixation within osteoporotic bone.

  18. Transdifferentiation of myoblasts into osteoblasts - possible use for bone therapy.

    PubMed

    Lin, Daphne P L; Carnagarin, Revathy; Dharmarajan, Arun; Dass, Crispin R

    2017-12-01

    Transdifferentiation is defined as the conversion of one cell type to another and is an ever-expanding field with a growing number of cells found to be capable of such a process. To date, the fact remains that there are limited treatment options for fracture healing, osteoporosis and bone repair post-destruction by bone tumours. Hence, this review focuses on the transdifferentiation of myoblast to osteoblast as a means to further understand the transdifferentiation process and to investigate a potential therapeutic option if successful. The potent osteoinductive effects of the bone morphogenetic protein-2 are largely implicated in the transdifferentiation of myoblast to osteoblast. Bone morphogenetic protein-2-induced activation of the Smad1 protein ultimately results in JunB synthesis, the first transcriptional step in myoblast dedifferentiation. The upregulation of the activating protein-1 binding activity triggers the transcription of the runt-related transcription factor 2 gene, a transcription factor that plays a major role in osteoblast differentiation. This potential transdifferentiation treatment may be utilised for dental implants, fracture healing, osteoporosis and bone repair post-destruction by bone tumours. © 2017 Royal Pharmaceutical Society.

  19. Clinical application of bone morphogenetic proteins for bone healing: a systematic review.

    PubMed

    Krishnakumar, Gopal Shankar; Roffi, Alice; Reale, Davide; Kon, Elizaveta; Filardo, Giuseppe

    2017-06-01

    This paper documents the existing evidence on bone morphogenetic proteins (BMPs) use for the treatment of bone fractures, non-union, and osteonecrosis, through a review of the clinical literature, underlying potential and limitations in terms of cost effectiveness and risk of complications. A systematic review was performed on the PubMed database using the following string: (bone morphogenetic proteins OR BMPs) and (bone repair OR bone regeneration) including papers from 2000 to 2016. The search focused on clinical trials dealing with BMPs application to favor bone regeneration in bone fractures, non-union, and osteonecrosis, in English language, with level of evidence I, II, III, and IV. Relevant data (type of study, number of patients, BMPs delivery material, dose, site, follow-up, outcome, and adverse events) were extracted and analyzed. Forty-four articles met the inclusion criteria: 10 randomized controlled trials (RCTs), 7 comparative studies, 18 case series, and 9 case reports. rhBMP-2 was documented mainly for the treatment of fractures, and rhBMP-7 mainly for non-unions and osteonecrosis. Mixed results were found among RCTs and comparative papers: 11 reported positive results for BMPs augmentation, 3 obtained no significant effects, and 2 showed negative results. The only study comparing the two BMPs showed a better outcome with rhBMP-2 for non-union treatment. Clinical evidence on BMPs use for the treatment of fractures, non-union, and osteonecrosis is still controversial, with the few available reports being mainly of low quality. While positive findings have been described in many studies, mixed results are still present in the literature in terms of efficacy and adverse events. The difficulties in drawing clear conclusions are also due to the studies heterogeneity, mainly in terms of different BMPs applied, with different concomitant treatments for each bone pathology. Therefore, further research with well-designed studies is needed in order to understand the real potential of this biological approach to favour bone healing.

  20. Effect of erythropoietin on mesenchymal stem cell differentiation and secretion in vitro in an acute kidney injury microenvironment.

    PubMed

    Liu, N M; Tian, J; Wang, W W; Han, G F; Cheng, J; Huang, J; Zhang, J Y

    2013-02-28

    We investigated the effect of erythropoietin (EPO) on differentiation and secretion of bone marrow-derived mesenchymal stem cells in an acute kidney injury microenvironment. Acute kidney injury mouse models were prepared. Both renal cortices were then immediately collected to produce the ischemia/reperfusion kidney homogenate supernatant. The morphological and ultrastructural changes in the cells were observed using an inverted microscope and a transmission electron microscope. Cytokeratin-18 was detected using flow cytometry. Bone morphogenetic protein-7 levels, hepatocyte growth factor, and vascular endothelial growth factor in the culture medium were detected using an enzyme-linked immunosorbent assay. The cells had high CD29 and CD44 expression, as well as low CD34 and CD45 expression. More round and oval cells with cobble-like appearances were observed after EPO treatment. In addition, an increase in the number of rough endoplasmic reticula, lysosomes, and mitochondria was observed in the cytoplasm; the intercellular junction peculiar to epithelial cells was also seen on the cell surface. After treatment with ischemia/reperfusion kidney homogenate supernatant, cytokeratin-18 expression increased significantly and EPO could magnify its expression. Bone morphogenetic protein-7 levels, hepatocyte growth factor, and vascular endothelial growth factor levels after treatment with ischemia/reperfusion kidney homogenate supernatant significantly decreased, whereas EPO increased the cytokine secretion. The acute kidney injury microenvironment can induce the bone marrow-derived mesenchymal stem cells to partially differentiate into renal tubular epithelium-shaped cells, but weaken their secretion function. EPO intervention can boost up their differentiation function and reverse their low secretion effect.

  1. Increased bone morphogenetic protein 7 signalling in the kidneys of dogs affected with a congenital portosystemic shunt.

    PubMed

    van Dongen, Astrid M; Heuving, Susanne M; Tryfonidou, Marianna A; van Steenbeek, Frank G; Rothuizen, Jan; Penning, Louis C

    2015-05-01

    Dogs with a congenital portosystemic shunt (CPSS) often have enlarged and hyper-filtrating kidneys. Although expression of different growth factors has been well-described in the livers of dogs affected with a CPSS, their expression in the kidneys has yet to be determined. Bone morphogenetic protein 7 (BMP-7), hepatocyte growth factor (HGF) and transforming growth factor (TGF)-β have been implicated in renal development (BMP-7, HGF) or the onset of renal fibrosis (TGF-β). Moreover, BMP-7 and HGF have protective properties in renal fibrosis. In this study, the expression and activity of BMP-7 were investigated in renal biopsies obtained from 13 dogs affected with a CPSS and compared to similar samples from age-matched healthy control dogs. Both quantitative reverse-transcriptase PCR and Western blotting showed up-regulated BMP-7 signalling in kidneys of CPPS-affected dogs. These research findings may help to explain the renal pathology/dysfunction in dogs affected with a CPSS. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The Efficacy of Cyclic Injection of Bone Morphogenetic Protein-2 in Large-Scale Calvarial Bone Defects.

    PubMed

    Choi, Jin Mi; Jeong, Woo Shik; Park, Eun Jung; Choi, Jong Woo

    2017-03-01

    Bone morphogenetic protein-2 (BMP-2) appears to be one of the most potent growth factors thus far studied. However, recent publications on the clinical application of BMP-2 revealed that its correct control is the paramount issue in clinical practice. For improving BMP-2 delivery, the cyclic administration might be an alternative. Accordingly, the authors cyclically injected BMP-2 in a cyclic injection model of large cranial defects to maintain the proper dosage during the bone healing process. A 10-mm diameter calvarial bone defect was produced using a round drill in 8-week-old Sprague-Dawley rats. Silk-hydroxyapatite scaffolds soaked in the appropriate concentration of BMP-2 were implanted into the defect. The animals were split into 4 single-injection groups and 3 multiple-injection groups; the latter groups received weekly subcutaneous injections of BMP-2 solution (1, 5, and 10 μg/mL) for 4 weeks, whereas the former groups received a single injection of BMP-2 at these concentrations. Each rat underwent computed tomography at 8 weeks. In terms of total volumes of the new bone, the 5 μg/mL multiple-injection BMP-2 group had significantly greater increases in bone volume than the single-injection groups. In terms of bone thickness, the multiple-injection groups had better outcomes than the single-injection groups. Thus, the cyclic injection protocol restored the original thickness without overgrowth. Cyclic injection of BMP-2 permits more accurate dosage control than single injection and improves thickness and dense bone regeneration. Therefore, it may represent a promising approach for future clinical trials. Further investigation using a greater number of animals is required.

  3. Novel Therapy for Bone Regeneration in Large Segmental Defects

    DTIC Science & Technology

    2017-12-01

    on fracture healing. Clin Orthop Relat Res. 1998;355(Suppl):S230–8. 37. Pape HC, Giannoudis PV. Fat embolism and IM nailing. Injury. 2006;37(Suppl 4...BMP), thrombopoietin (TPO), therapy, fracture healing, bone regeneration, minipig, pig 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT...2, TPO, or saline control. 2. KEYWORDS: Bone healing, bone morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing, bone

  4. The effect of locally delivered recombinant human bone morphogenetic protein-2 with hydroxyapatite/tri-calcium phosphate on the biomechanical properties of bone in diabetes-related osteoporosis.

    PubMed

    Liporace, Frank A; Breitbart, Eric A; Yoon, Richard S; Doyle, Erin; Paglia, David N; Lin, Sheldon

    2015-06-01

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) is particularly effective in improving osteogenesis in patients with diminished bone healing capabilities, such as individuals with type 1 diabetes mellitus (T1DM) who have impaired bone healing capabilities and increased risk of developing osteoporosis. This study measured the effects of rhBMP-2 treatment on osteogenesis by observing the dose-dependent effect of localized delivery of rhBMP-2 on biomechanical parameters of bone using a hydroxyapatite/tri-calcium phosphate (HA/TCP) carrier in a T1DM-related osteoporosis animal model. Two different doses of rhBMP-2 (LD low dose, HD high dose) with a HA/TCP carrier were injected into the femoral intramedullary canal of rats with T1DM-related osteoporosis. Two more diabetic rat groups were injected with saline alone and with HA/TCP carrier alone. Radiographs and micro-computed tomography were utilized for qualitative assessment of bone mineral density (BMD). Biomechanical testing occurred at 4- and 8-week time points; parameters tested included torque to failure, torsional rigidity, shear stress, and shear modulus. At the 4-week time point, the LD and HD groups both exhibited significantly higher BMD than controls; at the 8-week time point, the HD group exhibited significantly higher BMD than controls. Biomechanical testing revealed dose-dependent, higher trends in all parameters tested at the 4- and 8-week time points, with minimal significant differences. Groups treated with rhBMP-2 demonstrated improved bone mineral density at both 4 and 8 weeks compared to control saline groups, in addition to strong trends towards improvement of intrinsic and extrinsic biomechanical properties when compared to control groups. Data revealed trends toward dose-dependent increases in peak torque, torsional rigidity, shear stress, and shear modulus 4 weeks after rhBMP-2 treatment. Not applicable.

  5. Tricalcium phosphate and glutaraldehyde crosslinked gelatin incorporating bone morphogenetic protein--a viable scaffold for bone tissue engineering.

    PubMed

    Yang, Shu-Hua; Hsu, Chung-King; Wang, Kuo-Cheng; Hou, Sheng-Mou; Lin, Feng-Huei

    2005-07-01

    Bone defects caused by various etiologies must be filled with suitable substances to promote bone repair. Autogenous iliac crest graft is most frequently used, but is often associated with morbidities. Several bone graft substitutes have been developed to provide osteoconductive matrices as well as to enhance osteoinductivity. A tricalcium phosphate and glutaraldehyde crosslinked gelatin (GTG) scaffold, incorporated with bone morphogenetic proteins (BMPs), was developed to provide an alternative mean of bone tissue engineering. This study investigated differences between GTG and BMP-4 immobilized GTG (GTG-BMP) scaffolds on neonatal rat calvaria osteoblast activities. The GTG scaffold possessed an average pore size of 200 microm and a porosity of 75%. HE staining revealed uniform cell distribution throughout the scaffold 24 h post cell seeding. Alkaline phosphatase (ALP) activity of the GTG samples increased initially and then stabilized at 3 weeks postseeding. ALP activity of the GTG-BMP samples was similar to that of the GTG samples in the second and third weeks, but it continued increasing and became significantly greater than that of the GTG samples by the fourth week. Gla-type osteocalcin (Gla-OC) activity of the GTG-BMP samples was initially lower, but also became significantly greater than that of the GTG samples by the fourth week. An HE stain revealed greater numbers of attached cells and a richer matrix deposits in the GTG-BMP samples. A von Kossa stain showed larger mineralizing nodules, in greater numbers, after 4 weeks of in vitro cultivation. These findings suggest that the GTG scaffold provides an excellent porous structure, conductive to greater cell attachment and osteoblast differentiation, and that utility can be significantly enhanced by the inclusion of BMPs. A GTG-BMP scaffold holds promise as a superior bioactive material for bone tissue engineering. Copyright 2005 Wiley Periodicals, Inc.

  6. Local administration of bone morphogenetic protein-2 and bisphosphonate during non-weight-bearing treatment of ischemic osteonecrosis of the femoral head: an experimental investigation in immature pigs.

    PubMed

    Kim, Harry K W; Aruwajoye, Olumide; Du, Justin; Kamiya, Nobuhiro

    2014-09-17

    Non-weight-bearing decreases the femoral head deformity but increases bone resorption without increasing bone formation in an experimental animal model of Legg-Calvé-Perthes disease. We sought to determine if local administration of bone morphogenetic protein (BMP)-2 with or without bisphosphonate can increase the bone formation during the non-weight-bearing treatment in the large animal model of Legg-Calvé-Perthes disease. Eighteen piglets were surgically induced with femoral head ischemia. Immediately following the surgery, all animals received an above-the-knee amputation to enforce local non-weight-bearing (NWB). One to two weeks later, six animals received local BMP-2 to the necrotic head (BMP group), six received local BMP-2 and ibandronate (BMP+IB group), and the remaining six received no treatment (NWB group). All animals were killed at eight weeks after the induction of ischemia. Radiographic, microcomputed tomography (micro-CT), and histomorphometric assessments were performed. Radiographic assessment showed that the femoral heads in the NWB, BMP, and BMP+IB groups had a decrease of 20%, 14%, and 10%, respectively, in their mean epiphyseal quotient in comparison with the normal control group. Micro-CT analyses showed significantly higher femoral head bone volume in the BMP+IB group than in the BMP group (p = 0.02) and the NWB group (p < 0.001). BMP+IB and BMP groups had a significantly higher trabecular number (p < 0.01) and lower trabecular separation (p < 0.02) than the NWB group. In addition, the osteoclast number per bone surface was significantly lower in the BMP+IB group compared with the NWB group. Calcein labeling showed significantly higher bone formation in the BMP and BMP+IB groups than in the NWB group (p < 0.05). Heterotopic ossification was found in the capsule of four hips in the BMP+IB group but not in the BMP group. Administration of BMP-2 with bisphosphonate best decreased bone resorption and increased new bone formation during non-weight-bearing treatment of ischemic osteonecrosis in a pig model, but heterotopic ossification is a concern. This preclinical study provides new evidence that BMP-2 with bisphosphonate can effectively prevent the extreme bone loss associated with the non-weight-bearing treatment and increase new bone formation in the femoral head in this animal model of ischemic osteonecrosis. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

  7. Tissue engineering for lateral ridge augmentation with recombinant human bone morphogenetic protein 2 combination therapy: a case report.

    PubMed

    Mandelaris, George A; Spagnoli, Daniel B; Rosenfeld, Alan L; McKee, James; Lu, Mei

    2015-01-01

    This case report describes a tissue-engineered reconstruction with recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ ACS) + cancellous allograft and space maintenance via Medpor Contain mesh in the treatment of a patient requiring maxillary and mandibular horizontal ridge augmentation to enable implant placement. The patient underwent a previously unsuccessful corticocancellous bone graft at these sites. Multiple and contiguous sites in the maxilla and in the mandibular anterior, demonstrating advanced lateral ridge deficiencies, were managed using a tissue engineering approach as an alternative to autogenous bone harvesting. Four maxillary and three mandibular implants were placed 9 and 10 months, respectively, after tissue engineering reconstruction, and all were functioning successfully after 24 months of follow-up. Histomorphometric analysis of a bone core obtained at the time of the maxillary implant placement demonstrated a mean of 76.1% new vital bone formation, 22.2% marrow/cells, and 1.7% residual graft tissue. Tissue engineering for lateral ridge augmentation with combination therapy requires further research to determine predictability and limitations.

  8. Effects of alkaloids from Sophora flavescens on osteoblasts infected with Staphylococcus aureus and osteoclasts.

    PubMed

    Wang, Xuping; Zheng, Rongzong; Huang, Xiaowen; Mao, Zhujun; Wang, Nani; Li, Hongyu; Wen, Chengping; Shou, Dan

    2018-03-25

    Chronic osteomyelitis is primarily caused by infection with Staphylococcus aureus (S. aureus). Antibiotics are commonly administered; however, it is a challenge to promote bone healing. The aim of this study was to investigate the in vitro effects of alkaloids from the herbal remedy Sophora flavescens (ASF) on rat calvarial osteoblasts (ROBs) infected with S. aureus and healthy osteoclasts. Cell proliferation and alkaline phosphatase, interleukin-6, and tumour necrosis factor-α activity was measured in infected ROBs; tartrate-resistant acid phosphatase was evaluated in osteoclasts via enzyme-linked immunosorbent assay. The mRNA and protein expression levels of bone morphogenetic protein 2, runt-related transcription factor 2, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand were assessed in infected ROBs through reverse transcription-polymerase chain reaction and western blotting analysis, respectively. Results indicated that ASF increased the viability of uninfected ROBs and infected ROBs treated with vancomycin via regulation of bone morphogenetic protein 2, runt-related transcription factor, osteoprotegerin, and receptor activator of nuclear factor kappa-B ligand mRNA and protein expression levels. In addition, the secretion of the inflammatory factor tumour necrosis factor-α was decreased and alkaline phosphatase activity was increased, inhibiting the viability of osteoclasts and tartrate-resistant acid phosphatase activity. Therefore, the herbal remedy ASF has potential as a new treatment for chronic osteomyelitis. Copyright © 2018 John Wiley & Sons, Ltd.

  9. Novel Therapy for Bone Regeneration in Large Segmental Defects

    DTIC Science & Technology

    2016-10-01

    Giannoudis PV. Fat embolism and IM nailing. Injury. 2006;37(Suppl 4):S1–2. 38. Wenda K, Ritter G, Degreif J, Rudigier J. Pathogenesis of pul- monary... fracture healing, bone regeneration, minipig, pig 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF...saline control. 2. KEYWORDS: Bone healing, bone morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing, bone regeneration, minipig

  10. Evaluation of maxillary alveolar reconstruction using a resorbable collagen sponge with recombinant human bone morphogenetic protein-2 in cleft lip and palate patients.

    PubMed

    Alonso, Nivaldo; Tanikawa, Daniela Yukie Sakai; Freitas, Renato da Silva; Canan, Lady; Ozawa, Terumi Okada; Rocha, Diógenes Laércio

    2010-10-01

    A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%). For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.

  11. Injectable chitosan microparticles incorporating bone morphogenetic protein-7 for bone tissue regeneration

    PubMed Central

    Mantripragada, Venkata P.; Jayasuriya, Ambalangodage C.

    2014-01-01

    This study investigates the influence of the controlled release of bone morphogenetic protein 7 (BMP-7) from cross-linked chitosan microparticles on pre-osteoblasts (OB-6) in vitro. BMP-7 was incorporated into microparticles by encapsulation during the particle preparation and coating after particle preparation. Chitosan microparticles had an average diameter of 700 μm containing ~100 ng of BMP-7. The release study profile indicates that nearly 98% of the BMP-7 coated on the microparticles was released in a period of 18 days while only 36% of the BMP-7 encapsulated in the microparticles was released in the same time period. Cell attachment study indicated that the BMP-7 coated microparticles have many cells adhered on the microparticles in comparison with microparticles without growth factors on day 10. DNA assay indicated a statistical significant increase (p<0.05) in the amount of DNA obtained from BMP-7 encapsulated and coated microparticles in comparison with microparticles without any growth factors. A real time RT-PCR experiment was performed to determine the expression of a few osteoblast specific genes - Dlx5, runx2, osterix, osteopontin, osteocalcin, and bone sialoprotein. The results thus suggest that chitosan microparticles obtained by coacervation method are biocompatible and helps in improving the encapsulation efficiency of BMP-7. Also BMP-7 incorporated in the microparticles is being released in a controlled fashion to support attachment, proliferation and differentiation of pre-osteoblasts, thus acting as a good scaffold for bone tissue regeneration. PMID:24497318

  12. Strontium doping promotes bioactivity of rhBMP-2 upon calcium phosphate cement via elevated recognition and expression of BMPR-IA.

    PubMed

    Huang, Baolin; Tian, Yu; Zhang, Wenjing; Ma, Yifan; Yuan, Yuan; Liu, Changsheng

    2017-11-01

    Preserving and improving osteogenic activity of bone morphogenetic protein-2 (BMP-2) upon implants remains one of the key limitations in bone regeneration. With calcium phosphate cement (CPC) as model, we have developed a series of strontium (Sr)-doped CPC (SCPC) to address this issue. The effects of fixed Sr on the bioactivity of recombinant human BMP-2 (rhBMP-2) as well as the underlying mechanism were investigated. The results suggested that the rhBMP-2-induced osteogenic activity was significantly promoted upon SCPCs, especially with a low amount of fixed Sr (SrCO 3 content <10wt%). Further studies demonstrated that the Sr-induced enhancement of bioactivity of rhBMP-2 was related to an elevated recognition of bone morphogenetic protein receptor-IA (BMPR-IA) to rhBMP-2 and an increased expression of BMPR-IA in C2C12 model cells. As a result, the activations of BMP-induced signaling pathways were different in C2C12 cells incubated upon CPC/rhBMP-2 and SCPCs/rhBMP-2. These findings explicitly decipher the mechanism of SCPCs promoting osteogenic bioactivity of rhBMP-2 and signify the promising application of the SCPCs/rhBMP-2 matrix in bone regeneration implants. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Effects of ADMA upon Gene Expression: An Insight into the Pathophysiological Significance of Raised Plasma ADMA

    PubMed Central

    Smith, Caroline L; Anthony, Shelagh; Hubank, Mike; Leiper, James M; Vallance, Patrick

    2005-01-01

    Background Asymmetric dimethylarginine (ADMA) is a naturally occurring inhibitor of nitric oxide synthesis that accumulates in a wide range of diseases associated with endothelial dysfunction and enhanced atherosclerosis. Clinical studies implicate plasma ADMA as a major novel cardiovascular risk factor, but the mechanisms by which low concentrations of ADMA produce adverse effects on the cardiovascular system are unclear. Methods and Findings We treated human coronary artery endothelial cells with pathophysiological concentrations of ADMA and assessed the effects on gene expression using U133A GeneChips (Affymetrix). Changes in several genes, including bone morphogenetic protein 2 inducible kinase (BMP2K), SMA-related protein 5 (Smad5), bone morphogenetic protein receptor 1A, and protein arginine methyltransferase 3 (PRMT3; also known as HRMT1L3), were confirmed by Northern blotting, quantitative PCR, and in some instances Western blotting analysis to detect changes in protein expression. To determine whether these changes also occurred in vivo, tissue from gene deletion mice with raised ADMA levels was examined. More than 50 genes were significantly altered in endothelial cells after treatment with pathophysiological concentrations of ADMA (2 μM). We detected specific patterns of changes that identify pathways involved in processes relevant to cardiovascular risk and pulmonary hypertension. Changes in BMP2K and PRMT3 were confirmed at mRNA and protein levels, in vitro and in vivo. Conclusion Pathophysiological concentrations of ADMA are sufficient to elicit significant changes in coronary artery endothelial cell gene expression. Changes in bone morphogenetic protein signalling, and in enzymes involved in arginine methylation, may be particularly relevant to understanding the pathophysiological significance of raised ADMA levels. This study identifies the mechanisms by which increased ADMA may contribute to common cardiovascular diseases and thereby indicates possible targets for therapies. PMID:16190779

  14. Analysis of Recombinant Human Bone Morphogenetic Protein-2 Use in the Treatment of Lumbar Degenerative Spondylolisthesis.

    PubMed

    Yao, Qingqiang; Cohen, Jeremiah R; Buser, Zorica; Park, Jong-Beom; Brodke, Darrel S; Meisel, Hans-Joerg; Youssef, Jim A; Wang, Jeffrey C; Yoon, S Tim

    2016-12-01

    Study Design  Retrospective database review. Objective  To identify trends of the recombinant human bone morphogenetic protein-2 (rhBMP-2) use in the treatment of lumbar degenerative spondylolisthesis (LDS). Methods  PearlDiver Patient Record Database was used to identify patients who underwent lumbar fusion for LDS between 2005 and 2011. The distribution of bone morphogenetic protein use rate (BR) in various surgical procedures was recorded. Patient numbers, reoperation numbers, BR, and per year BR (PYBR) were stratified by geographic region, gender, and age. Results  There were 11,335 fusion surgeries, with 3,461 cases using rhBMP-2. Even though PYRB increased between 2005 and 2008, there was a significant decrease in 2010 for each procedure: 404 (34.5%) for posterior interbody fusion, 1,282 (34.3%) for posterolateral plus posterior interbody fusion (PLPIF), 1,477 (29.2%) for posterolateral fusion, and 335 (22.4%) for anterior lumbar interbody fusion. In patients using rhBMP-2, the reoperation rate was significantly lower than in patients not using rhBMP-2 (0.69% versus 1.07%, p  < 0.0001). Male patients had higher PYBR compared with female patients in 2008 and 2009 ( p  < 0.05). The West region and PLPIF had the highest BR and PYBR. Conclusions Our data shows that the revision rates were significantly lower in patients treated with rhBMP-2 compared with patients not treated with rhBMP-2. Furthermore, rhBMP-2 use in LDS varied by year, region, gender, and type of fusion technique. In the West region, the posterior approach and patients 65 to 69 years of age had the highest rate of rhBMP-2 use.

  15. Analysis of Recombinant Human Bone Morphogenetic Protein-2 Use in the Treatment of Lumbar Degenerative Spondylolisthesis

    PubMed Central

    Yao, Qingqiang; Cohen, Jeremiah R.; Buser, Zorica; Park, Jong-Beom; Brodke, Darrel S.; Meisel, Hans-Joerg; Youssef, Jim A.; Wang, Jeffrey C.; Yoon, S. Tim

    2016-01-01

    Study Design Retrospective database review. Objective To identify trends of the recombinant human bone morphogenetic protein-2 (rhBMP-2) use in the treatment of lumbar degenerative spondylolisthesis (LDS). Methods PearlDiver Patient Record Database was used to identify patients who underwent lumbar fusion for LDS between 2005 and 2011. The distribution of bone morphogenetic protein use rate (BR) in various surgical procedures was recorded. Patient numbers, reoperation numbers, BR, and per year BR (PYBR) were stratified by geographic region, gender, and age. Results There were 11,335 fusion surgeries, with 3,461 cases using rhBMP-2. Even though PYRB increased between 2005 and 2008, there was a significant decrease in 2010 for each procedure: 404 (34.5%) for posterior interbody fusion, 1,282 (34.3%) for posterolateral plus posterior interbody fusion (PLPIF), 1,477 (29.2%) for posterolateral fusion, and 335 (22.4%) for anterior lumbar interbody fusion. In patients using rhBMP-2, the reoperation rate was significantly lower than in patients not using rhBMP-2 (0.69% versus 1.07%, p < 0.0001). Male patients had higher PYBR compared with female patients in 2008 and 2009 (p < 0.05). The West region and PLPIF had the highest BR and PYBR. Conclusions Our data shows that the revision rates were significantly lower in patients treated with rhBMP-2 compared with patients not treated with rhBMP-2. Furthermore, rhBMP-2 use in LDS varied by year, region, gender, and type of fusion technique. In the West region, the posterior approach and patients 65 to 69 years of age had the highest rate of rhBMP-2 use. PMID:27853658

  16. The Controversy Surrounding Bone Morphogenetic Proteins in the Spine: A Review of Current Research

    PubMed Central

    Hustedt, Joshua W.; Blizzard, Daniel J.

    2014-01-01

    Bone morphogenetic proteins have been in use in spinal surgery since 2002. These proteins are members of the TGF-beta superfamily and guide mesenchymal stem cells to differentiate into osteoblasts to form bone in targeted tissues. Since the first commercial BMP became available in 2002, a host of research has supported BMPs and they have been rapidly incorporated in spinal surgeries in the United States. However, recent controversy has arisen surrounding the ethical conduct of the research supporting the use of BMPs. Yale University Open Data Access (YODA) recently teamed up with Medtronic to offer a meta-analysis of the effectiveness of BMPs in spinal surgery. This review focuses on the history of BMPs and examines the YODA research to guide spine surgeons in their use of BMP in spinal surgery. PMID:25506287

  17. Bone Morphogenetic Protein (BMP) signaling in development and human diseases

    PubMed Central

    Wang, Richard N.; Green, Jordan; Wang, Zhongliang; Deng, Youlin; Qiao, Min; Peabody, Michael; Zhang, Qian; Ye, Jixing; Yan, Zhengjian; Denduluri, Sahitya; Idowu, Olumuyiwa; Li, Melissa; Shen, Christine; Hu, Alan; Haydon, Rex C.; Kang, Richard; Mok, James; Lee, Michael J.; Luu, Hue L.; Shi, Lewis L.

    2014-01-01

    Bone Morphogenetic Proteins (BMPs) are a group of signaling molecules that belongs to the Transforming Growth Factor-β (TGF-β) superfamily of proteins. Initially discovered for their ability to induce bone formation, BMPs are now known to play crucial roles in all organ systems. BMPs are important in embryogenesis and development, and also in maintenance of adult tissue homeostasis. Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects, highlighting the essential functions of BMPs. In this review, we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development. A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling. PMID:25401122

  18. Effects of Recombinant Human Bone Morphogenetic Protein-2 on Vertical Bone Augmentation in a Canine Model.

    PubMed

    Hsu, Yung-Ting; Al-Hezaimi, Khalid; Galindo-Moreno, Pablo; O'Valle, Francisco; Al-Rasheed, Abdulaziz; Wang, Hom-Lay

    2017-09-01

    Vertical bone augmentation (VBA) remains unpredictable and challenging for most clinicians. This study aims to compare hard tissue outcomes of VBA, with and without recombinant human bone morphogenetic protein (rhBMP)-2, under space-making titanium mesh in a canine model. Eleven male beagle dogs were used in the study. Experimental ridge defects were created to form atrophic ridges. VBA was performed via guided bone regeneration using titanium mesh and allografts. In experimental hemimandibles, rhBMP-2/absorbable collagen sponge was well mixed with allografts prior to procedures, whereas a control buffer was applied within controls. Dogs were euthanized after a 4-month healing period. Clinical and radiographic examinations were performed to assess ridge dimensional changes. In addition, specimens were used for microcomputed tomography (micro-CT) assessment and histologic analysis. Membrane exposure was found on five of 11 (45.5%) rhBMP-2-treated sites, whereas it was found on nine of 11 (81.8%) non-rhBMP-2-treated sites. Within 4 months of healing, rhBMP-2-treated sites showed better radiographic bone density, greater defect fill, and significantly more bone gain in ridge height (P <0.05) than controls. Experimental hemimandibles exhibited lower rates of membrane exposure and a noteworthy, ectopic bone formation above the mesh in 72% of sites. Results from micro-CT also suggested a trend of less vertical bone gain and bone mineral density in controls (P >0.05). Under light microscope, predominant lamellar patterns were found in the specimen obtained from rhBMP-2 sites. With inherent limitations of the canine model and the concern of such a demanding surgical technique, current findings suggest that the presence of rhBMP-2 in a composite graft allows an increase of vertical gain, with formation of ectopic bone over the titanium mesh in comparison with non-rhBMP-2 sites.

  19. TNF-α Upregulates Expression of BMP-2 and BMP-3 Genes in the Rat Dental Follicle – Implications for Tooth Eruption

    PubMed Central

    Yao, Shaomian; Prpic, Veronica; Pan, Fenghui; Wise, Gary E.

    2011-01-01

    The dental follicle appears to regulate both the alveolar bone resorption and bone formation needed for tooth eruption. Tumor necrosis factor-alpha ( TNF-α) gene expression is maximally upregulated at postnatal day 9 in the rat dental follicle of the 1st mandibular molar, a time that correlates with rapid bone growth at the base of the tooth crypt, as well as a minor burst of osteoclastogenesis. TNF-α expression is correlated with the expression of bone morphogenetic protein-2 (BMP-2), a molecule expressed in the dental follicle that can promote bone formation. Because BMP-2 signaling may be augmented by bone morphogenetic protein-3 (BMP-3), it was the objective of this study to determine 1) if the dental follicle expresses BMP-3 and 2) if TNF-α stimulates the dental follicle cells to express BMP-2 and BMP-3. Dental follicles were collected from different postnatal ages of rat pups. Dental follicle cells were incubated with TNF-α to study its dosage and time-course effects on gene expression of BMP-2 and BMP-3, as determined by real-time RT-PCR. Next, immunostaining was conducted to confirm if the protein was synthesized and ELISA of the conditioned medium was conducted to determine if BMP-2 was secreted. We found that BMP-3 expression is correlated with the expression of TNF-α in the dental follicle and TNF-α significantly increased BMP-2 and BMP-3 expression in vitro. Immunostaining and ELISA showed that BMP-2 and BMP-3 were synthesized and secreted. This study suggests that TNF-α can upregulate the expression of bone formation genes that may be needed for tooth eruption. PMID:20067418

  20. Novel Therapy for Bone Regeneration in Large Segmental Defects

    DTIC Science & Technology

    2017-12-01

    healing. Clin Orthop Relat Res. 1998;355(Suppl):S230–8. 37. Pape HC, Giannoudis PV. Fat embolism and IM nailing. Injury. 2006;37(Suppl 4):S1–2. 38. Wenda...mechanisms to elicit bone healing. 15. SUBJECT TERMS Bone healing, bone morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing...thrombopoietin (TPO), therapy, fracture healing, bone regeneration, minipig, pig 3. OVERALL PROJECT SUMMARY: Project start date 30/09/2013 Project end

  1. Exaggerated inflammatory response after use of recombinant bone morphogenetic protein in recurrent unicameral bone cysts.

    PubMed

    MacDonald, Kevin M; Swanstrom, Morgan M; McCarthy, James J; Nemeth, Blaise A; Guliani, Teresa A; Noonan, Kenneth J

    2010-03-01

    Recurrent unicameral bone cysts (UBCs) can result in significant morbidity during a child's physical and emotional development. Multiple treatment options are available and a review of the literature fails to clearly define the optimal treatment for UBCs. Recombinant bone morphogenetic protein (BMP) has been used with success in other disorders of poor bone formation. This manuscript is the first to report on the use of recombinant BMP in the treatment of UBCs. Three patients with recurrent UBCs underwent revision surgery with recombinant BMP. Radiographic and medical review was performed and is reported here. In these patients, the use of BMP failed to fully resolve their UBC; 2 patients had complete recurrence that required further surgery. In addition to poor radiographic results, all patients developed exaggerated inflammatory responses in the acute postoperative period. Each child developed clinically significant limb swelling and pain that mimicked infection. On the basis of our poor radiographic results and a paradoxical clinical result, we no longer recommend the use of recombinant BMP in the manner reported here for the treatment of recurrent UBCs. Level IV, case series.

  2. Novel Wnt Regulator NEL-Like Molecule-1 Antagonizes Adipogenesis and Augments Osteogenesis Induced by Bone Morphogenetic Protein 2

    PubMed Central

    Shen, Jia; James, Aaron W.; Zhang, Xinli; Pang, Shen; Zara, Janette N.; Asatrian, Greg; Chiang, Michael; Lee, Min; Khadarian, Kevork; Nguyen, Alan; Lee, Kevin S.; Siu, Ronald K.; Tetradis, Sotirios; Ting, Kang; Soo, Chia

    2017-01-01

    The differentiation factor NEL-like molecule-1 (NELL-1) has been reported as osteoinductive in multiple in vivo preclinical models. Bone morphogenetic protein (BMP)-2 is used clinically for skeletal repair, but in vivo administration can induce abnormal, adipose-filled, poor-quality bone. We demonstrate that NELL-1 combined with BMP2 significantly optimizes osteogenesis in a rodent femoral segmental defect model by minimizing the formation of BMP2-induced adipose-filled cystlike bone. In vitro studies using the mouse bone marrow stromal cell line M2-10B4 and human primary bone marrow stromal cells have confirmed that NELL-1 enhances BMP2-induced osteogenesis and inhibits BMP2-induced adipogenesis. Importantly, the ability of NELL-1 to direct BMP2-treated cells toward osteogenesis and away from adipogenesis requires intact canonical Wnt signaling. Overall, these studies establish the feasibility of combining NELL-1 with BMP2 to improve clinical bone regeneration and provide mechanistic insight into canonical Wnt pathway activity during NELL-1 and BMP2 osteogenesis. The novel abilities of NELL-1 to stimulate Wnt signaling and to repress adipogenesis may highlight new treatment approaches for bone loss in osteoporosis. PMID:26772960

  3. Coordinated Proliferation and Differentiation of Human-Induced Pluripotent Stem Cell-Derived Cardiac Progenitor Cells Depend on Bone Morphogenetic Protein Signaling Regulation by GREMLIN 2

    PubMed Central

    Bylund, Jeffery B.; Trinh, Linh T.; Awgulewitsch, Cassandra P.; Paik, David T.; Jetter, Christopher; Jha, Rajneesh; Zhang, Jianhua; Nolan, Kristof; Xu, Chunhui; Thompson, Thomas B.; Kamp, Timothy J.

    2017-01-01

    Heart development depends on coordinated proliferation and differentiation of cardiac progenitor cells (CPCs), but how the two processes are synchronized is not well understood. Here, we show that the secreted Bone Morphogenetic Protein (BMP) antagonist GREMLIN 2 (GREM2) is induced in CPCs shortly after cardiac mesoderm specification during differentiation of human pluripotent stem cells. GREM2 expression follows cardiac lineage differentiation independently of the differentiation method used, or the origin of the pluripotent stem cells, suggesting that GREM2 is linked to cardiogenesis. Addition of GREM2 protein strongly increases cardiomyocyte output compared to established procardiogenic differentiation methods. Our data show that inhibition of canonical BMP signaling by GREM2 is necessary to promote proliferation of CPCs. However, canonical BMP signaling inhibition alone is not sufficient to induce cardiac differentiation, which depends on subsequent JNK pathway activation specifically by GREM2. These findings may have broader implications in the design of approaches to orchestrate growth and differentiation of pluripotent stem cell-derived lineages that depend on precise regulation of BMP signaling. PMID:28125926

  4. Coordinated Proliferation and Differentiation of Human-Induced Pluripotent Stem Cell-Derived Cardiac Progenitor Cells Depend on Bone Morphogenetic Protein Signaling Regulation by GREMLIN 2.

    PubMed

    Bylund, Jeffery B; Trinh, Linh T; Awgulewitsch, Cassandra P; Paik, David T; Jetter, Christopher; Jha, Rajneesh; Zhang, Jianhua; Nolan, Kristof; Xu, Chunhui; Thompson, Thomas B; Kamp, Timothy J; Hatzopoulos, Antonis K

    2017-05-01

    Heart development depends on coordinated proliferation and differentiation of cardiac progenitor cells (CPCs), but how the two processes are synchronized is not well understood. Here, we show that the secreted Bone Morphogenetic Protein (BMP) antagonist GREMLIN 2 (GREM2) is induced in CPCs shortly after cardiac mesoderm specification during differentiation of human pluripotent stem cells. GREM2 expression follows cardiac lineage differentiation independently of the differentiation method used, or the origin of the pluripotent stem cells, suggesting that GREM2 is linked to cardiogenesis. Addition of GREM2 protein strongly increases cardiomyocyte output compared to established procardiogenic differentiation methods. Our data show that inhibition of canonical BMP signaling by GREM2 is necessary to promote proliferation of CPCs. However, canonical BMP signaling inhibition alone is not sufficient to induce cardiac differentiation, which depends on subsequent JNK pathway activation specifically by GREM2. These findings may have broader implications in the design of approaches to orchestrate growth and differentiation of pluripotent stem cell-derived lineages that depend on precise regulation of BMP signaling.

  5. Essential Roles of Epithelial Bone Morphogenetic Protein Signaling During Prostatic Development

    PubMed Central

    Omori, Akiko; Miyagawa, Shinichi; Ogino, Yukiko; Harada, Masayo; Ishii, Kenichiro; Sugimura, Yoshiki; Ogino, Hajime; Nakagata, Naomi

    2014-01-01

    Prostate is a male sex-accessory organ. The prostatic epithelia consist primarily of basal and luminal cells that differentiate from embryonic urogenital sinus epithelia. Prostate tumors are believed to originate in the basal and luminal cells. However, factors that promote normal epithelial differentiation have not been well elucidated, particularly for bone morphogenetic protein (Bmp) signaling. This study shows that Bmp signaling prominently increases during prostatic differentiation in the luminal epithelia, which is monitored by the expression of phosphorylated Smad1/5/8. To elucidate the mechanism of epithelial differentiation and the function of Bmp signaling during prostatic development, conditional male mutant mouse analysis for the epithelial-specific Bmp receptor 1a (Bmpr1a) was performed. We demonstrate that Bmp signaling is indispensable for luminal cell maturation, which regulates basal cell proliferation. Expression of the prostatic epithelial regulatory gene Nkx3.1 was significantly reduced in the Bmpr1a mutants. These results indicate that Bmp signaling is a key factor for prostatic epithelial differentiation, possibly by controlling the prostatic regulatory gene Nkx3.1. PMID:24731097

  6. Improving Bone Formation in a Rat Femur Segmental Defect by Controlling Bone Morphogenetic Protein-2 Release

    DTIC Science & Technology

    2011-04-01

    tissue and polymer: mineralized tissue stained dark green, osteoid and collagen bright red, soft tissue pink to light green, and erythrocytes bright...of bone, soft tissue , and polymer, high-resolution digital images were acquired at 1.25 · or 20 · . The area of interest comprising the bone defect...bone, soft tissue , and polymer (when present) within the defect were quantified using Metamorph software (Molecular Devices, Inc.) and were calculated

  7. Coating with a Modular Bone Morphogenetic Peptide Promotes Healing of a Bone-Implant Gap in an Ovine Model

    PubMed Central

    Lu, Yan; Lee, Jae Sung; Nemke, Brett; Graf, Ben K.; Royalty, Kevin; Illgen, Richard; Vanderby, Ray; Markel, Mark D.; Murphy, William L.

    2012-01-01

    Despite the potential for growth factor delivery strategies to promote orthopedic implant healing, there is a need for growth factor delivery methods that are controllable and amenable to clinical translation. We have developed a modular bone growth factor, herein termed “modular bone morphogenetic peptide (mBMP)”, which was designed to efficiently bind to the surface of orthopedic implants and also stimulate new bone formation. The purpose of this study was to coat a hydroxyapatite-titanium implant with mBMP and evaluate bone healing across a bone-implant gap in the sheep femoral condyle. The mBMP molecules efficiently bound to a hydroxyapatite-titanium implant and 64% of the initially bound mBMP molecules were released in a sustained manner over 28 days. The results demonstrated that the mBMP-coated implant group had significantly more mineralized bone filling in the implant-bone gap than the control group in C-arm computed tomography (DynaCT) scanning (25% more), histological (35% more) and microradiographic images (50% more). Push-out stiffness of the mBMP group was nearly 40% greater than that of control group whereas peak force did not show a significant difference. The results of this study demonstrated that mBMP coated on a hydroxyapatite-titanium implant stimulates new bone formation and may be useful to improve implant fixation in total joint arthroplasty applications. PMID:23185610

  8. Ontogeny of the maxilla in Neanderthals and their ancestors

    PubMed Central

    Lacruz, Rodrigo S.; Bromage, Timothy G.; O'Higgins, Paul; Arsuaga, Juan-Luis; Stringer, Chris; Godinho, Ricardo Miguel; Warshaw, Johanna; Martínez, Ignacio; Gracia-Tellez, Ana; de Castro, José María Bermúdez; Carbonell, Eudald

    2015-01-01

    Neanderthals had large and projecting (prognathic) faces similar to those of their putative ancestors from Sima de los Huesos (SH) and different from the retracted modern human face. When such differences arose during development and the morphogenetic modifications involved are unknown. We show that maxillary growth remodelling (bone formation and resorption) of the Devil's Tower (Gibraltar 2) and La Quina 18 Neanderthals and four SH hominins, all sub-adults, show extensive bone deposition, whereas in modern humans extensive osteoclastic bone resorption is found in the same regions. This morphogenetic difference is evident by ∼5 years of age. Modern human faces are distinct from those of the Neanderthal and SH fossils in part because their postnatal growth processes differ markedly. The growth remodelling identified in these fossil hominins is shared with Australopithecus and early Homo but not with modern humans suggesting that the modern human face is developmentally derived. PMID:26639346

  9. Ontogeny of the maxilla in Neanderthals and their ancestors.

    PubMed

    Lacruz, Rodrigo S; Bromage, Timothy G; O'Higgins, Paul; Arsuaga, Juan-Luis; Stringer, Chris; Godinho, Ricardo Miguel; Warshaw, Johanna; Martínez, Ignacio; Gracia-Tellez, Ana; de Castro, José María Bermúdez; Carbonell, Eudald

    2015-12-07

    Neanderthals had large and projecting (prognathic) faces similar to those of their putative ancestors from Sima de los Huesos (SH) and different from the retracted modern human face. When such differences arose during development and the morphogenetic modifications involved are unknown. We show that maxillary growth remodelling (bone formation and resorption) of the Devil's Tower (Gibraltar 2) and La Quina 18 Neanderthals and four SH hominins, all sub-adults, show extensive bone deposition, whereas in modern humans extensive osteoclastic bone resorption is found in the same regions. This morphogenetic difference is evident by ∼5 years of age. Modern human faces are distinct from those of the Neanderthal and SH fossils in part because their postnatal growth processes differ markedly. The growth remodelling identified in these fossil hominins is shared with Australopithecus and early Homo but not with modern humans suggesting that the modern human face is developmentally derived.

  10. Bone morphogenetic protein 4 and bone morphogenetic protein receptor expression in the pituitary gland of adult dogs in healthy condition and with ACTH-secreting pituitary adenoma.

    PubMed

    Sato, A; Ochi, H; Harada, Y; Yogo, T; Kanno, N; Hara, Y

    2017-01-01

    The purpose of this study was to investigate the expression of bone morphogenetic protein 4 (BMP4) and its receptors, bone morphogenetic protein receptor I (BMPRI) and BMPRII, in the pituitary gland of healthy adult dogs and in those with ACTH-secreting pituitary adenoma. Quantitative polymerase chain reaction analysis showed that the BMP4 messenger RNA expression level in the ACTH-secreting pituitary adenoma samples was significantly lower than that in the normal pituitary gland samples (P = 0.03). However, there were no statistically significant differences between samples with respect to the messenger RNA expression levels of the receptors BMPRIA, BMPRIB, and BMPRII. Double-immunofluorescence analysis of the normal canine pituitary showed that BMP4 was localized in the thyrotroph (51.3 ± 7.3%) and not the corticotroph cells. By contrast, BMPRII was widely expressed in the thyrotroph (19.9 ± 5.2%) and somatotroph cells (94.7 ± 3.6%) but not in the corticotroph cells (P < 0.001, thyrotroph cells vs somatotroph cells). Similarly, in ACTH-secreting pituitary adenoma, BMP4 and BMPRII were not expressed in the corticotroph cells. Moreover, the percentage of BMP4-positive cells was also significantly reduced in the thyrotroph cells of the surrounding normal pituitary tissue obtained from the resected ACTH-secreting pituitary adenoma (8.3 ± 7.9%) compared with that in normal canine pituitary (P < 0.001). BMP4 has been reported to be expressed in corticotroph cells in the human pituitary gland. Therefore, the results of this study reveal a difference in the cellular pattern of BMP4-positive staining in the pituitary gland between humans and dogs and further revealed the pattern of BMPRII-positive staining in the dog pituitary gland. These species-specific differences regarding BMP4 should be considered when using dogs as an animal model for Cushing's disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Acemannan sponges stimulate alveolar bone, cementum and periodontal ligament regeneration in a canine class II furcation defect model.

    PubMed

    Chantarawaratit, P; Sangvanich, P; Banlunara, W; Soontornvipart, K; Thunyakitpisal, P

    2014-04-01

    Periodontal disease is a common infectious disease, found worldwide, causing the destruction of the periodontium. The periodontium is a complex structure composed of both soft and hard tissues, thus an agent applied to regenerate the periodontium must be able to stimulate periodontal ligament, cementum and alveolar bone regeneration. Recent studies demonstrated that acemannan, a polysaccharide extracted from Aloe vera gel, stimulated both soft and hard tissue healing. This study investigated effect of acemannan as a bioactive molecule and scaffold for periodontal tissue regeneration. Primary human periodontal ligament cells were treated with acemannan in vitro. New DNA synthesis, expression of growth/differentiation factor 5 and runt-related transcription factor 2, expression of vascular endothelial growth factor, bone morphogenetic protein-2 and type I collagen, alkaline phosphatase activity, and mineralized nodule formation were determined using [(3)H]-thymidine incorporation, reverse transcription-polymerase chain reaction, enzyme-linked immunoabsorbent assay, biochemical assay and alizarin red staining, respectively. In our in vivo study, premolar class II furcation defects were made in four mongrel dogs. Acemannan sponges were applied into the defects. Untreated defects were used as a negative control group. The amount of new bone, cementum and periodontal ligament formation were evaluated 30 and 60 d after the operation. Acemannan significantly increased periodontal ligament cell proliferation, upregulation of growth/differentiation factor 5, runt-related transcription factor 2, vascular endothelial growth factor, bone morphogenetic protein 2, type I collagen and alkaline phosphatase activity, and mineral deposition as compared with the untreated control group in vitro. Moreover, acemannan significantly accelerated new alveolar bone, cementum and periodontal ligament formation in class II furcation defects. Our data suggest that acemannan could be a candidate biomolecule for periodontal tissue regeneration. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. High doses of bone morphogenetic protein 2 induce structurally abnormal bone and inflammation in vivo.

    PubMed

    Zara, Janette N; Siu, Ronald K; Zhang, Xinli; Shen, Jia; Ngo, Richard; Lee, Min; Li, Weiming; Chiang, Michael; Chung, Jonguk; Kwak, Jinny; Wu, Benjamin M; Ting, Kang; Soo, Chia

    2011-05-01

    The major Food and Drug Association-approved osteoinductive factors in wide clinical use are bone morphogenetic proteins (BMPs). Although BMPs can promote robust bone formation, they also induce adverse clinical effects, including cyst-like bone formation and significant soft tissue swelling. In this study, we evaluated multiple BMP2 doses in a rat femoral segmental defect model and in a minimally traumatic rat femoral onlay model to determine its dose-dependent effects. Results of our femoral segmental defect model established a low BMP2 concentration range (5 and 10 μg/mL, total dose 0.375 and 0.75 μg in 75 μg total volume) unable to induce defect fusion, a mid-range BMP2 concentration range able to fuse the defect without adverse effects (30 μg/mL, total dose 2.25 μg in 75 μg total volume), and a high BMP2 concentration range (150, 300, and 600 μg/mL, total dose 11.25, 22.5, and 45 μg in 75 μg total volume) able to fuse the defect, but with formation of cyst-like bony shells filled with histologically confirmed adipose tissue. In addition, compared to control, 4 mg/mL BMP2 also induced significant tissue inflammatory infiltrates and exudates in the femoral onlay model that was accompanied by increased numbers of osteoclast-like cells at 3, 7, and 14 days. Overall, we consistently reproduced BMP2 side effects of cyst-like bone and soft tissue swelling using high BMP2 concentration approaching the typical human 1500 μg/mL.

  13. High Doses of Bone Morphogenetic Protein 2 Induce Structurally Abnormal Bone and Inflammation In Vivo

    PubMed Central

    Zara, Janette N.; Siu, Ronald K.; Zhang, Xinli; Shen, Jia; Ngo, Richard; Lee, Min; Li, Weiming; Chiang, Michael; Chung, Jonguk; Kwak, Jinny; Wu, Benjamin M.; Ting, Kang

    2011-01-01

    The major Food and Drug Association–approved osteoinductive factors in wide clinical use are bone morphogenetic proteins (BMPs). Although BMPs can promote robust bone formation, they also induce adverse clinical effects, including cyst-like bone formation and significant soft tissue swelling. In this study, we evaluated multiple BMP2 doses in a rat femoral segmental defect model and in a minimally traumatic rat femoral onlay model to determine its dose-dependent effects. Results of our femoral segmental defect model established a low BMP2 concentration range (5 and 10 μg/mL, total dose 0.375 and 0.75 μg in 75 μg total volume) unable to induce defect fusion, a mid-range BMP2 concentration range able to fuse the defect without adverse effects (30 μg/mL, total dose 2.25 μg in 75 μg total volume), and a high BMP2 concentration range (150, 300, and 600 μg/mL, total dose 11.25, 22.5, and 45 μg in 75 μg total volume) able to fuse the defect, but with formation of cyst-like bony shells filled with histologically confirmed adipose tissue. In addition, compared to control, 4 mg/mL BMP2 also induced significant tissue inflammatory infiltrates and exudates in the femoral onlay model that was accompanied by increased numbers of osteoclast-like cells at 3, 7, and 14 days. Overall, we consistently reproduced BMP2 side effects of cyst-like bone and soft tissue swelling using high BMP2 concentration approaching the typical human 1500 μg/mL. PMID:21247344

  14. Bone regeneration by implantation of adipose-derived stromal cells expressing BMP-2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li Huiwu; Health and Science Center, SIBS CAS and SSMU, 225 South Chongqing Road, Shanghai 200025; Dai Kerong

    2007-05-18

    In this study, we reported that the adipose-derived stromal cells (ADSCs) genetically modified by bone morphogenetic protein 2 (BMP-2) healed critical-sized canine ulnar bone defects. First, the osteogenic and adipogenic differentiation potential of the ADSCs derived from canine adipose tissue were demonstrated. And then the cells were modified by the BMP-2 gene and the expression and bone-induction ability of BMP-2 were identified. Finally, the cells modified by BMP-2 gene were applied to a {beta}-tricalcium phosphate (TCP) carrier and implanted into ulnar bone defects in the canine model. After 16 weeks, radiographic, histological, and histomorphometry analysis showed that ADSCs modified bymore » BMP-2 gene produced a significant increase of newly formed bone area and healed or partly healed all of the bone defects. We conclude that ADSCs modified by the BMP-2 gene can enhance the repair of critical-sized bone defects in large animals.« less

  15. Efficient delivery of recombinant human bone morphogenetic protein (rhBMP-2) with dextran sulfate-chitosan microspheres.

    PubMed

    Xia, Yuan-Jun; Xia, Hong; Chen, Ling; Ying, Qing-Shui; Yu, Xiang; Li, Li-Hua; Wang, Jian-Hua; Zhang, Ying

    2018-04-01

    Bone morphogenetic protein-2 (BMP-2) serves an important role in the development of bone and cartilage. However, administration of BMP-2 protein alone by intravenous delivery is not very effective. Sustained delivery of stabilized BMP-2 by carriers has been proven necessary to improve the osteogenesis effect of BMP-2. The present study constructed a novel drug delivery system using dextran sulfate (DS)-chitosan (CS) microspheres and investigated the efficiency of the delivery system on recombinant human bone morphogenetic protein (rhBMP-2). The microsphere morphology, optimal ratio of DS/CS/rhBMP-2, and drug loading rate and entrapment efficiency of rhBMP-2 CS nanoparticles were determined. L929 cells were used to evaluate the cytotoxicity and effect of DS/CS/rhBMP-2 microspheres on cell proliferation. Differentiation study was conducted using bone marrow mesenchymal stem cells (BMSCs-C57) cells treated with DS/CS/rhBMP-2 microspheres or the control microspheres. The DS/CS/rhBMP-2 microspheres delivery system was successfully established. Subsequent complexation of rhBMP-2-bound DS with polycations afforded well defined microspheres with a diameter of ~250 nm. High protein entrapment efficiency (85.6%) and loading ratio (47.245) µg/mg were achieved. Release of rhBMP-2 from resultant microspheres persisted for over 20 days as determined by ELISA assay. The bioactivity of rhBMP-2 encapsulated in the CS/DS microsphere was observed to be well preserved as evidenced by the alkaline phosphatase activity assay and calcium nodule formation of BMSCs-C57 incubated with rhBMP-2-loaded microspheres. The results demonstrated that microspheres based on CS-DS polyion complexes were a highly efficient vehicle for delivery of rhBMP-2 protein. The present study may provide novel orientation for bone tissue engineering for repairing and regenerating bone defects.

  16. Chitosan scaffolds containing calcium phosphate salts and rhBMP-2: in vitro and in vivo testing for bone tissue regeneration.

    PubMed

    Guzmán, Rodrigo; Nardecchia, Stefania; Gutiérrez, María C; Ferrer, María Luisa; Ramos, Viviana; del Monte, Francisco; Abarrategi, Ander; López-Lacomba, José Luis

    2014-01-01

    Numerous strategies that are currently used to regenerate bone depend on employing biocompatible materials exhibiting a scaffold structure. These scaffolds can be manufactured containing particular active compounds, such as hydroxyapatite precursors and/or different growth factors to enhance bone regeneration process. Herein, we have immobilized calcium phosphate salts (CPS) and bone morphogenetic protein 2 (BMP-2)--combined or alone--into chitosan scaffolds using ISISA process. We have analyzed whether the immobilized bone morphogenetic protein preserved its osteoinductive capability after manufacturing process as well as BMP-2 in vitro release kinetic. We have also studied both the in vitro and in vivo biocompatibility of the resulting scaffolds using a rabbit model. Results indicated that rhBMP-2 remained active in the scaffolds after the manufacturing process and that its release kinetic was different depending on the presence of CPS. In vitro and in vivo findings showed that cells grew more in scaffolds with both CPS and rhBMP-2 and that these scaffolds induced more bone formation in rabbit tibia. Thus chitosan scaffolds containing both CPS and rhBMP-2 were more osteoinductive than their counterparts alone indicating that could be useful for bone regeneration purposes, such as some applications in dentistry.

  17. Palatogenesis: morphogenetic and molecular mechanisms of secondary palate development

    PubMed Central

    Bush, Jeffrey O.; Jiang, Rulang

    2012-01-01

    Mammalian palatogenesis is a highly regulated morphogenetic process during which the embryonic primary and secondary palatal shelves develop as outgrowths from the medial nasal and maxillary prominences, respectively, remodel and fuse to form the intact roof of the oral cavity. The complexity of control of palatogenesis is reflected by the common occurrence of cleft palate in humans. Although the embryology of the palate has long been studied, the past decade has brought substantial new knowledge of the genetic control of secondary palate development. Here, we review major advances in the understanding of the morphogenetic and molecular mechanisms controlling palatal shelf growth, elevation, adhesion and fusion, and palatal bone formation. PMID:22186724

  18. Recombinant human bone morphogenetic protein-2 for grade III open segmental tibial fractures from combat injuries in Iraq.

    PubMed

    Kuklo, T R; Groth, A T; Anderson, R C; Frisch, H M; Islinger, R B

    2008-08-01

    This is a retrospective consecutive case series of 138 Gustillo-Anderson type IIIB and IIIC segmental tibial fractures treated at Walter Reed Army Medical Center in soldiers injured in Iraq between March 2003 and March 2005. Five patients with a head injury and four who were lost to follow-up were excluded. The patients were treated definitively with either a ringed external fixator or a reamed intramedullary nail, evaluated in terms of supplementary bone grafting with either autogenous bone (group 1, 67 patients) or recombinant human bone morphogenetic protein-2 at 1.50 mg/ml applied to an absorbable collagen sponge (group 2, 62 patients). The mechanism of injury, defect size and classification, associated injuries, presence of infection, preliminary treatment/fixation, number of procedures before definitive management, time to and details of definitive management, subsequent infection, re-operation, smoking history and other complications were noted. Radiographs were assessed for union, delayed union or nonunion by an independent investigator. All the patients were male. Their mean age was 26.6 years (20 to 42) and the mean follow-up was for 15.6 months (12 to 32). Group 2 had a slightly higher profile of concomitant injuries and a slightly worse fracture classification, but these were not significant. The rate of union was 76% (51 of 67) for group 1 and 92% for group 2 (57 of 62; p = 0.015). There was also a higher rate of subsequent infection in group 1 (14.9%) compared with group 2 (3.2%; p = 0.001) and a higher rate of re-operation (28%) in group 1 (p = 0.003). There were no observed hypersensitivity reactions to the recombinant human bone morphogenetic protein-2 implant.

  19. Radiographic comparison of different concentrations of recombinant human bone morphogenetic protein with allogenic bone compared with the use of 100% mineralized cancellous bone allograft in maxillary sinus grafting.

    PubMed

    Froum, Stuart J; Wallace, Stephen; Cho, Sang-Choon; Khouly, Ismael; Rosenberg, Edwin; Corby, Patricia; Froum, Scott; Mascarenhas, Patrick; Tarnow, Dennis P

    2014-01-01

    The purpose of this study was to radiographically evaluate, then analyze, bone height, volume, and density with reference to percentage of vital bone after maxillary sinuses were grafted using two different doses of recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ACS) combined with mineralized cancellous bone allograft (MCBA) and a control sinus grafted with MCBA only. A total of 18 patients (36 sinuses) were used for analysis of height and volume measurements, having two of three graft combinations (one in each sinus): (1) control, MCBA only; (2) test 1, MCBA + 5.6 mL of rhBMP-2/ACS (containing 8.4 mg of rhBMP-2); and (3) test 2, MCBA + 2.8 mL of rhBMP-2/ACS (containing 4.2 mg of rhBMP-2). The study was completed with 16 patients who also had bilateral cores removed 6 to 9 months following sinus augmentation. A computer software system was used to evaluate 36 computed tomography scans. Two time points where selected for measurements of height: The results indicated that height of the grafted sinus was significantly greater in the treatment groups compared with the control. However, by the second time point, there were no statistically significant differences. Three weeks post-surgery bone volume measurements showed similar statistically significant differences between test and controls. However, prior to core removal, test group 1 with the greater dose of rhBMP-2 showed a statistically significant greater increase compared with test group 2 and the control. There was no statistically significant difference between the latter two groups. All three groups had similar volume and shrinkage. Density measurements varied from the above results, with the control showing statistically significant greater density at both time points. By contrast, the density increase over time in both rhBMP groups was similar and statistically higher than in the control group. There were strong associations between height and volume in all groups and between volume and new vital bone only in the control group. There were no statistically significant relationships observed between height and bone density or between volume and bone density for any parameter measured. More cases and monitoring of the future survival of implants placed in these augmented sinuses are needed to verify these results.

  20. Neurologic impairment from ectopic bone in the lumbar canal: a potential complication of off-label PLIF/TLIF use of bone morphogenetic protein-2 (BMP-2).

    PubMed

    Wong, David A; Kumar, Anant; Jatana, Sanjay; Ghiselli, Gary; Wong, Katherine

    2008-01-01

    Bone morphogenetic protein-2 (BMP-2) (Infuse) has been approved for use in anterior lumbar fusion in conjunction with an LT cage. However, off-label use is seen with anterior cervical fusion, posterior lumbar interbody fusion (PLIF), and transforaminal lumbar interbody fusion (TLIF). The Federal Food and Drug Administration trial of BMP-2 in a PLIF application was halted because of a high incidence of ectopic bone forming in the neural canal (75%). The authors did not find a correlation between ectopic bone and increased leg pain. They concluded that the ectopic bone was a radiographic phenomenon and not associated with clinical findings. Complications using BMP in the cervical spine have been reported. Heretofore, there has not been a similar warning voiced for use of BMP in a lumbar PLIF or TLIF. The purpose was to report five cases of ectopic bone in the canal associated with PLIF/TLIF off-label use of BMP-2 potentially contributing to abnormal neurologic findings. This is an observational cohort study of patients referred to a tertiary care private medical center. This was a retrospective chart review of patients referred to a tertiary spine institute with complications after surgery where BMP-2 had been used in an off-label PLIF or TLIF application. Patient demographics, operating room (OR) notes from the index BMP surgery, imaging studies, and current clinical status were reviewed. Five cases of ectopic bone in the spinal canal with potential neurologic compromise were identified. It does appear that ectopic bone in the spinal canal associated with BMP-2 use in PLIF or TLIF may contribute to symptomatic neurologic findings in rare cases. Revision surgeries are difficult. This article challenges a previous publication, which concluded that the high incidence of ectopic bone was of no clinical significance. Isolating BMP anteriorly in the disc space using layered barriers of bone graft between the BMP and the annular defect may reduce the incidence of ectopic bone in the spinal canal. Surgeons need to weigh the benefits versus risks of any technology used off label when making treatment decisions with their patients.

  1. Screening of Osteogenic-Enhancing Short Peptides from BMPs for Biomimetic Material Applications

    PubMed Central

    Kanie, Kei; Kurimoto, Rio; Tian, Jing; Ebisawa, Katsumi; Narita, Yuji; Honda, Hiroyuki; Kato, Ryuji

    2016-01-01

    Bone regeneration is an important issue in many situations, such as bone fracture and surgery. Umbilical cord mesenchymal stem cells (UC-MSCs) are promising cell sources for bone regeneration. Bone morphogenetic proteins and their bioactive peptides are biomolecules known to enhance the osteogenic differentiation of MSCs. However, fibrosis can arise during the development of implantable biomaterials. Therefore, it is important to control cell organization by enhancing osteogenic proliferation and differentiation and inhibiting fibroblast proliferation. Thus, we focused on the screening of such osteogenic-enhancing peptides. In the present study, we developed new peptide array screening platforms to evaluate cell proliferation and alkaline phosphatase activity in osteoblasts, UC-MSCs and fibroblasts. The conditions for the screening platform were first defined using UC-MSCs and an osteogenic differentiation peptide known as W9. Next, in silico screening to define the candidate peptides was carried out to evaluate the homology of 19 bone morphogenetic proteins. Twenty-five candidate 9-mer peptides were selected for screening. Finally, the screening of osteogenic-enhancing (osteogenic cell-selective proliferation and osteogenic differentiation) short peptide was carried out using the peptide array method, and three osteogenic-enhancing peptides were identified, confirming the validity of this screening. PMID:28773850

  2. Lack of Association of Bone Morphogenetic Protein 2 Gene Haplotypes with Bone Mineral Density, Bone Loss, or Risk of Fractures in Men

    PubMed Central

    Varanasi, Satya S.; Tuck, Stephen P.; Mastana, Sarabjit S.; Dennison, Elaine; Cooper, Cyrus; Vila, Josephine; Francis, Roger M.; Datta, Harish K.

    2011-01-01

    Introduction. The association of bone morphogenetic protein 2 (BMP2) with BMD and risk of fracture was suggested by a recent linkage study, but subsequent studies have been contradictory. We report the results of a study of the relationship between BMP2 genotypes and BMD, annual change in BMD, and risk of fracture in male subjects. Materials and Methods. We tested three single-nucleotide polymorphisms (SNPs) across the BMP2 gene, including Ser37Ala SNP, in 342 Caucasian Englishmen, comprising 224 control and 118 osteoporotic subjects. Results. BMP2 SNP1 (Ser37Ala) genotypes were found to have similar low frequency in control subjects and men with osteoporosis. The major informative polymorphism, BMP2 SNP3 (Arg190Ser), showed no statistically significant association with weight, height, BMD, change in BMD at hip or lumbar spine, and risk of fracture. Conclusion. There were no genotypic or haplotypic effects of the BMP2 candidate gene on BMD, change in BMD, or fracture risk identified in this cohort. PMID:22013543

  3. Early inhibitory effects of zoledronic acid in tooth extraction sockets in dogs are negated by recombinant human bone morphogenetic protein.

    PubMed

    Gerard, David A; Carlson, Eric R; Gotcher, Jack E; Pickett, David O

    2014-01-01

    This study was conducted with 2 purposes. The first was to determine the effect of a single dose of zoledronic acid (ZA) on the healing of a tooth extraction socket in dogs. The second was to determine if placement of recombinant human bone morphogenetic protein-2 (rhBMP-2)/absorbable collagen sponge (ACS) - INFUSE, (Medtronic, Memphis, TN) into these extraction sockets would inhibit the inhibition on bone healing and remodeling by ZA. Nine adult female beagle dogs (2 to 3 yr old) were placed into 3 groups of 3 dogs each. Group I received 15 mL of sterile saline intravenously; group II received 2.5 mg of ZA intravenously; and group III received 5 mg of ZA intravenously. Forty-five days after treatment, all dogs underwent extraction of noncontiguous right and left mandibular first molars and second premolars. In group I, the right mandibular extraction sockets had nothing placed in them, whereas the left mandibular sockets had only ACS placed in them. In groups II and III, the right mandibular sockets had rhBMP-2/ACS placed in them, whereas the left mandibular sockets had only ACS placed. All extraction sockets were surgically closed. Tetracycline was given intravenously 5 and 12 days later, and all animals were euthanized 15 days after tooth extraction. The extraction sockets and rib and femur samples were harvested immediately after euthanasia, processed, and studied microscopically. A single dose of ZA significantly inhibited healing and bone remodeling in the area of the tooth extractions. The combination of rhBMP-2/ACS appeared to over-ride some of the bone remodeling inhibition of the ZA and increased bone fill in the extraction sites, and remodeling activity in the area was noted. The effects of rhBMP-2/ACS were confined to the area of the extraction sockets because bone activity at distant sites was not influenced. A single dose of ZA administered intravenously inhibits early healing of tooth extraction sockets and bone remodeling in this animal model. The combination of rhBMP-2/ACS significantly increased bone fill and bone remodeling in these areas, negating much of the effect of the ZA. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  4. Lack of effect of bone morphogenetic protein 2 and 4 gene polymorphisms on bone density in postmenopausal Turkish women.

    PubMed

    Ozkan, Z S; Deveci, D; Onalan Etem, E; Yüce, H

    2010-11-30

    We investigated the effect of bone morphogenetic protein 2 and 4 (BMP-2 and -4) gene polymorphisms on bone density in postmenopausal Turkish women with osteoporosis. The frequency of single-nucleotide polymorphisms (SNPs) of BMP-2 and -4 genes was analyzed in 101 osteoporotic-postmenopausal women and 52 postmenopausal women with positive bone mineral density scores. We evaluated the frequency of the thymine→cytosine nucleotide variation at position 538 for BMP-4 and the transposition of adenine→thymine at codon 190 for BMP-2, with PCR. The proportions of genotypes observed for the BMP-2 SNP in the osteoporotic group were AA (47.5%), AT (39.6%), TT (12.9%), and in the non-osteoporotic group they were AA (48.1%), AT (40.4%), TT (11.5%). The corresponding frequencies for the BMP-4 SNP in the osteoporotic group were TT (30.7%), TC (45.5%), CC (23.8%), and in the non-osteoporotic group they were TT (26.9%), TC (40.4%), CC (32.7%). There were no significant differences in the frequencies of these genotypes between the patient and control groups. We conclude that genetic variations in BMP-2 and -4 do not substantially contribute to lumbar spine bone mineral density in postmenopausal Turkish women.

  5. Strategies for delivering bone morphogenetic protein for bone healing.

    PubMed

    Begam, Howa; Nandi, Samit Kumar; Kundu, Biswanath; Chanda, Abhijit

    2017-01-01

    Bone morphogenetic proteins (BMPs) are the most significant growth factors that belong to the Transforming Growth Factor Beta (TGF-β) super-family. Though more than twenty members of this family have been identified so far in humans, Food and Drug Administration (FDA) approved two growth factors: BMP-2 and BMP-7 for treatments of spinal fusion and long-bone fractures with collagen carriers. Currently BMPs are clinically used in spinal fusion, oral and maxillofacial surgery and also in the repair of long bone defects. The efficiency of BMPs depends a lot on the selection of suitable carriers. At present, different types of carrier materials are used: natural and synthetic polymers, calcium phosphate and ceramic-polymer composite materials. Number of research articles has been published on the minute intricacies of the loading process and release kinetics of BMPs. Despite the significant evidence of its potential for bone healing demonstrated in animal models, future clinical investigations are needed to define dose, scaffold and route of administration. The efficacy and application of BMPs in various levels with a proper carrier and dose is yet to be established. The present article collates various aspects of success and limitation and identifies the prospects and challenges associated with the use of BMPs in orthopaedic surgery. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Long-Segment Fusion for Adult Spinal Deformity Correction Using Low-Dose Recombinant Human Bone Morphogenetic Protein-2: A Retrospective Review of Fusion Rates.

    PubMed

    Schmitt, Paul J; Kelleher, John P; Ailon, Tamir; Heller, Joshua E; Kasliwal, Manish K; Shaffrey, Christopher I; Smith, Justin S

    2016-08-01

    Although use of very high-dose recombinant human bone morphogenetic protein-2 (rhBMP-2) has been reported to markedly improve fusion rates in adult spinal deformity (ASD) surgery, most centers use much lower doses due to cost constraints. How effective these lower doses are for fusion enhancement remains unclear. To assess fusion rates using relatively low-dose rhBMP-2 for ASD surgery. This was a retrospective review of consecutive ASD patients that underwent thoracic to sacral fusion. Patients that achieved 2-year follow-up were analyzed. Impact of patient and surgical factors on fusion rate was assessed, and fusion rates were compared with historical cohorts. Of 219 patients, 172 (78.5%) achieved 2-year follow-up and were analyzed. Using an average rhBMP-2 dose of 3.1 mg/level (average total dose = 35.9 mg/case), the 2-year fusion rate was 73.8%. Cancellous allograft, local autograft, and very limited iliac crest bone graft (<20 mL, obtained during iliac bolt placement) were also used. On multivariate analysis, female sex was associated with a higher fusion rate, whereas age, comorbidity score, deformity type, and 3-column osteotomy were not. There were no complications directly attributable to rhBMP-2. Fusion rates for ASD using low-dose rhBMP-2 were comparable to those reported for iliac crest bone graft but lower than for high-dose rhBMP-2. Importantly, there were substantial differences between patients in the present series and those in the historical comparison groups that could not be fully adjusted for based on available data. Prospective evaluation of rhBMP-2 dosing for ASD surgery is warranted to define the most appropriate dose that balances benefits, risks, and costs. ASD, adult spinal deformityICBG, iliac crest bone graftOR, odds ratiorhBMP-2, recombinant human bone morphogenetic protein-2RR, risk ratioTCO, 3-column osteotomy.

  7. Nell-1-Induced Bone Regeneration in Calvarial Defects

    PubMed Central

    Aghaloo, Tara; Cowan, Catherine M.; Chou, Yu-Fen; Zhang, Xinli; Lee, Haofu; Miao, Steve; Hong, Nichole; Kuroda, Shun’ichi; Wu, Benjamin; Ting, Kang; Soo, Chia

    2006-01-01

    Many craniofacial birth defects contain skeletal components requiring bone grafting. We previously identified the novel secreted osteogenic molecule NELL-1, first noted to be overexpressed during premature bone formation in calvarial sutures of craniosynostosis patients. Nell-1 overexpression significantly increases differentiation and mineralization selectively in osteoblasts, while newborn Nell-1 transgenic mice significantly increase premature bone formation in calvarial sutures. In the current study, cultured calvarial explants isolated from Nell-1 transgenic newborn mice (with mild sagittal synostosis) demonstrated continuous bone growth and overlapping sagittal sutures. Further investigation into gene expression cascades revealed that fibroblast growth factor-2 and transforming growth factor-β1 stimulated Nell-1 expression, whereas bone morphogenetic protein (BMP)-2 had no direct effect. Additionally, Nell-1-induced osteogenesis in MC3T3-E1 osteoblasts through reduction in the expression of early up-regulated osteogenic regulators (OSX and ALP) but induction of later markers (OPN and OCN). Grafting Nell-1 protein-coated PLGA scaffolds into rat calvarial defects revealed the osteogenic potential of Nell-1 to induce bone regeneration equivalent to BMP-2, whereas immunohistochemistry indicated that Nell-1 reduced osterix-producing cells and increased bone sialoprotein, osteocalcin, and BMP-7 expression. Insights into Nell-1-regulated osteogenesis coupled with its ability to stimulate bone regeneration revealed a potential therapeutic role and an alternative to the currently accepted techniques for bone regeneration. PMID:16936265

  8. Si-Wu-tang extract stimulates bone formation through PI3K/Akt/NF-κB signaling pathways in osteoblasts.

    PubMed

    Wu, Chi-Ming; Chen, Po-Chun; Li, Te-Mao; Fong, Yi-Chin; Tang, Chih-Hsin

    2013-10-24

    Si-Wu-Tang (SWT), a Traditional Chinese Medicine (TCM) formula, is widely used for the treatment of gynopathies diseases such as menstrual discomfort, climacteric syndrome, dysmenorrhea, and other estrogen-related diseases. Recent studies have shown that SWT can treat primary dysmenorrhea, have anti-pruritic anti-inflammatory effects, and protect against radiation-induced bone marrow damage in an animal model. It has been reported that anti-inflammatory and anti-oxidant agents have the potential to treat osteoporosis by increasing bone formation and/or suppressing bone resorption. However, the effect of SWT on bone cell function has not yet been reported. Alkaline phosphatase (ALP), bone morphogenetic proteins (BMP)-2, and osteopontin (OPN) mRNA expression was analyzed by qPCR. The mechanism of action of SWT extract was investigated using western blotting. The in vivo anti-osteoporotic effect of SWT extract was assessed in ovariectomized mice. Here, we report that SWT increases ALP, BMP-2, and OPN expression as well as bone mineralization. In addition, we show that the PI3K, Akt, and NF-κB signaling pathways may be involved in the SWT-mediated increase in gene expression and bone mineralization. Notably, treatment of mice with SWT extract prevented bone loss induced by ovariectomy in vivo. SWT may be used to stimulate bone formation for the treatment of osteoporosis.

  9. Hydrogel Delivery of Mesenchymal Stem Cell–Expressing Bone Morphogenetic Protein-2 Enhances Bone Defect Repair

    PubMed Central

    Hsiao, Hui-Yi; Yang, Shu-Rui; Brey, Eric M.; Chu, I-Ming

    2016-01-01

    Background: The application of bone tissue engineering for repairing bone defects has gradually shown some satisfactory progress. One of the concerns raising scientific attention is the poor supply of growth factors. A number of growth factor delivery approaches have been developed for promoting bone formation. However, there is no systematic comparison of those approaches on efficiency of neobone formation. In this study, the approaches using periosteum, direct supply of growth factors, or gene transfection of growth factors were evaluated to determine the osteogenic capacity on the repair of bone defect. Methods: In total, 42 male 21-week-old Sprague-Dawley rats weighing 250 to 400 g were used as the bone defect model to evaluate the bone repair efficiency. Various tissue engineered constructs of poly(ethylene glycol)-poly(l-lactic acid) (PEG-PLLA) copolymer hydrogel with periosteum, with external supply of bone morphogenetic protein-2 (BMP2), or with BMP2-transfected bone marrow–derived mesenchymal stem cells (BMMSCs) were filled in a 7-mm bone defect region. Animals were euthanized at 3 months, and the hydrogel constructs were harvested. The evaluation with histological staining and radiography analysis were performed for the volume of new bone formation. Results: The PEG-PLLA scaffold with BMMSCs promotes bone regeneration with the addition of periosteum. The group with BMP2-transfected BMMSCs demonstrated the largest volume of new bone among all the testing groups. Conclusions: Altogether, the results of this study provide the evidence that the combination of PEG-PLLA hydrogels with BMMSCs and sustained delivery of BMP2 resulted in the maximal bone regeneration. PMID:27622106

  10. Establishment of a cell line producing bone morphogenetic protein from a human osteosarcoma.

    PubMed

    Takaoka, K; Yoshikawa, H; Masuhara, K; Sugamoto, K; Tsuda, T; Aoki, Y; Ono, K; Sakamoto, Y

    1989-07-01

    A human osteosarcoma cell line was established from a biopsy specimen from a 13-year-old girl. The osteosarcoma tissue was maintained in athymic nude mice (Balb C nu/nu) by serial transplantation for three years. The tumor was excised from a host mouse and digested with collagenase. The isolated cells were cultured by 98 passages in 14 months, and clones of osteosarcoma cells were obtained by limiting dilution. A clone named human osteosarcoma cell 6 (H-OS-6) that showed the osteoblastic phenotypes of productions of bone morphogenetic protein (BMP) and alkaline phosphatase and a response to human parathyroid hormone (h-PTH 1-34) was selected. The morphology of its chromosomes indicated its human origin. This human osteosarcoma cell line is unique in producing BMP under in vitro conditions.

  11. Vascular endothelial growth factor/bone morphogenetic protein-2 bone marrow combined modification of the mesenchymal stem cells to repair the avascular necrosis of the femoral head

    PubMed Central

    Ma, Xiao-Wei; Cui, Da-Ping; Zhao, De-Wei

    2015-01-01

    Vascular endothelial cell growth factor (VEGF) combined with bone morphogenetic protein (BMP) was used to repair avascular necrosis of the femoral head, which can maintain the osteogenic phenotype of seed cells, and effectively secrete VEGF and BMP-2, and effectively promote blood vessel regeneration and contribute to formation and revascularization of tissue engineered bone tissues. To observe the therapeutic effect on the treatment of avascular necrosis of the femoral head by using bone marrow mesenchymal stem cells (BMSCs) modified by VEGF-165 and BMP-2 in vitro. The models were avascular necrosis of femoral head of rabbits on right leg. There groups were single core decompression group, core decompression + BMSCs group, core decompression + VEGF-165/BMP-2 transfect BMSCs group. Necrotic bone was cleared out under arthroscope. Arthroscopic observation demonstrated that necrotic bone was cleared out in each group, and fresh blood flowed out. Histomorphology determination showed that blood vessel number and new bone area in the repair region were significantly greater at various time points following transplantation in the core decompression + VEGF-165/BMP-2 transfect BMSCs group compared with single core decompression group and core decompression + BMSCs group (P < 0.05). These suggested that VEGF-165/BMP-2 gene transfection strengthened osteogenic effects of BMSCs, elevated number and quality of new bones and accelerated the repair of osteonecrosis of the femoral head. PMID:26629044

  12. [Mechanobiology and bone metabolism: Clinical relevance for fracture treatment].

    PubMed

    Haffner-Luntzer, M; Liedert, A; Ignatius, A

    2015-12-01

    Mechanical stimuli are known to significantly influence bone metabolism and fracture healing. Various studies have demonstrated the involvement of complex molecular mechanotransduction pathways, such as the Wnt/beta-catenin, bone morphogenetic protein (BMP) and estrogen receptor signaling pathways in mechanotransduction. Mechanotransduction is influenced by aging and the comorbidities of the patient. Pharmacological modulation of signal transduction influences bone formation and the mechanosensitivity of skeletal tissue. The combination of pharmacological and biomechanical therapies may be useful for the treatment of fractures with impaired healing.

  13. Activated protein C (APC) can increase bone anabolism via a protease-activated receptor (PAR)1/2 dependent mechanism.

    PubMed

    Shen, Kaitlin; Murphy, Ciara M; Chan, Ben; Kolind, Mille; Cheng, Tegan L; Mikulec, Kathy; Peacock, Lauren; Xue, Meilang; Park, Sang-Youel; Little, David G; Jackson, Chris J; Schindeler, Aaron

    2014-12-01

    Activated Protein C (APC) is an anticoagulant with strong cytoprotective properties that has been shown to promote wound healing. In this study APC was investigated for its potential orthopedic application using a Bone Morphogenetic Protein 2 (rhBMP-2) induced ectopic bone formation model. Local co-administration of 10 µg rhBMP-2 with 10 µg or 25 µg APC increased bone volume at 3 weeks by 32% (N.S.) and 74% (p<0.01) compared to rhBMP-2 alone. This was associated with a significant increase in CD31+ and TRAP+ cells in tissue sections of ectopic bone, consistent with enhanced vascularity and bone turnover. The actions of APC are largely mediated by its receptors endothelial protein C receptor (EPCR) and protease-activated receptors (PARs). Cultured pre-osteoblasts and bone nodule tissue sections were shown to express PAR1/2 and EPCR. When pre-osteoblasts were treated with APC, cell viability and phosphorylation of ERK1/2, Akt, and p38 were increased. Inhibition with PAR1 and sometimes PAR2 antagonists, but not with EPCR blocking antibodies, ameliorated the effects of APC on cell viability and kinase phosphorylation. These data indicate that APC can affect osteoblast viability and signaling, and may have in vivo applications with rhBMP-2 for bone repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  14. Influences of Reduced Expression of Maternal Bone Morphogenetic Protein 2 on Embryonic Development

    PubMed Central

    Singh, Ajeet P.; Castranio, Trisha; Scott, Greg; Guo, Dayong; Harris, Marie A.; Ray, Manas; Harris, Stephan E.; Mishina, Yuji

    2009-01-01

    Bone morphogenetic protein 2 (BMP2) was originally found by its osteoinductive ability, and recent genetic analyses have revealed that it plays critical roles during early embryogenesis, cardiogenesis, decidualization as well as skeletogenesis. During a course of evaluation of the conditional allele for Bmp2, we found that the presence of a neo cassette, a selection marker needed for gene targeting events in embryonic stem cells, in the 3’ untranslated region of exon 3 of Bmp2, reduced the expression levels of Bmp2 both in embryonic and maternal tissues. Some of the embryos that were genotyped as transheterozygous for the floxed allele with the neo cassette over the conventional null allele (fn/−) showed a lethal phenotype including defects in cephalic neural tube closure and ventral abdominal wall closure. Embryos exhibiting these abnormalities were increased when genotypes of the pregnant females were different; when expression levels of Bmp2 in maternal tissues were lower, a larger proportion of fn/− embryos exhibit these abnormalities. These results suggest that the expression levels of Bmp2 together in both in embryonic and maternal tissues influence the normal neural tube closure and body wall closure with different thresholds. PMID:18769073

  15. In vitro and in vivo evaluation of bone morphogenetic protein-2 (BMP-2) immobilized collagen-coated polyetheretherketone (PEEK)

    NASA Astrophysics Data System (ADS)

    Du, Ya-Wei; Zhang, Li-Nan; Ye, Xin; Nie, He-Min; Hou, Zeng-Tao; Zeng, Teng-Hui; Yan, Guo-Ping; Shang, Peng

    2015-03-01

    Polyetheretherketone (PEEK) is regarded as one of the most potential candidates of biomaterials in spinal implant applications. However, as a bioinert material, PEEK plays a limited role in osteoconduction and osseointegration. In this study, recombinant human bone morphogenetic protein-2 (rhBMP-2) was immobilized onto the surface of collagen-coated PEEK in order to prepare a multi-functional material. After adsorbed onto the PEEK surface by hydrophobic interaction, collagen was cross-linked with N-(3-dimethylaminopropyl)-N'-ethyl carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). EDC/NHS system also contributed to the immobilization of rhBMP-2. Water contact angle tests, XPS and SEM clearly demonstrated the surface changes. ELISA tests quantified the amount of rhBMP-2 immobilized and the release over a period of 30 d. In vitro evaluation proved that the osteogenesis differentiation rate was higher when cells were cultured on modified PEEK discs than on regular ones. In vivo tests were conducted and positive changes of major parameters were presented. This report demonstrates that the rhBMP-2 immobilized method for PEEK modification increase bioactivity in vitro and in vivo, suggesting its practicability in orthopedic and spinal clinical applications.

  16. Prefabricated microvascular autograft in tracheal reconstruction.

    PubMed

    Fayad, J; Kuriloff, D B

    1994-10-01

    Tracheal reconstruction continues to be a challenge in head and neck surgery. Numerous techniques, including the use of alloplasts, composite grafts, and staged laryngotracheal troughs, have met with limited success because of implant exposure, infection, persistent granulation tissue, and eventual restenosis. With recently introduced techniques for soft-tissue molding, bone induction with bone morphogenetic protein, and microvascular free tissue transfer, a rodent model was developed to create a well-vascularized tracheal autograft. In this model, a rigid tube having the same dimensions and flexibility as the native trachea was created by wrapping a cylindrical silicone tracheal mold with a layer of vascularized adductor thigh muscle pedicled on the femoral vessels in the groin. Tracheal rings were created by filing transverse troughs in the muscle bed with bone morphogenetic protein-primed demineralized bone matrix before wrapping around the silicone mold. Grafts harvested at 2 weeks demonstrated rigid skeletal support provided by heterotopic bone formation in the form of rings and a smooth inner lining produced by fibroplasia. Bone transformation was controlled and restricted to the muscle troughs, allowing intervening regions of soft tissue and thus producing a flexible neotrachia. With this model, a homologous, vascularized tracheal autograft capable of microvascular free tissue transfer was fabricated based on the femoral vessels. Prefabrication of composite grafts, through the use of soft-tissue molding, bone induction, and subsequent free tissue transfer, has an unlimited potential for use in head and neck reconstruction.

  17. Bone morphogenetic proteins: a powerful osteoinductive compound with non-negligible side effects and limitations.

    PubMed

    Oryan, Ahmad; Alidadi, Soodeh; Moshiri, Ali; Bigham-Sadegh, Amin

    2014-01-01

    Healing and regeneration of large bone defects leading to non-unions is a great concern in orthopedic surgery. Since auto- and allografts have limitations, bone tissue engineering and regenerative medicine (TERM) has attempted to solve this issue. In TERM, healing promotive factors are necessary to regulate the several important events during healing. An ideal treatment strategy should provide osteoconduction, osteoinduction, osteogenesis, and osteointegration of the graft or biomaterials within the healing bone. Since many materials have osteoconductive properties, only a few biomaterials have osteoinductive properties which are important for osteogenesis and osteointegration. Bone morphogenetic proteins (BMPs) are potent inductors of the osteogenic and angiogenic activities during bone repair. The BMPs can regulate the production and activity of some growth factors which are necessary for the osteogenesis. Since the introduction of BMP, it has added a valuable tool to the surgeon's possibilities and is most commonly used in bone defects. Despite significant evidences suggesting their potential benefit on bone healing, there are some evidences showing their side effects such as ectopic bone formation, osteolysis and problems related to cost effectiveness. Bone tissue engineering may create a local environment, using the delivery systems, which enables BMPs to carry out their activities and to lower cost and complication rate associated with BMPs. This review represented the most important concepts and evidences regarding the role of BMPs on bone healing and regeneration from basic to clinical application. The major advantages and disadvantages of such biologic compounds together with the BMPs substitutes are also discussed. © 2014 International Union of Biochemistry and Molecular Biology.

  18. Stepwise verification of bone regeneration using recombinant human bone morphogenetic protein-2 in rat fibula model

    PubMed Central

    2017-01-01

    Objectives The purpose of this study was to introduce our three experiments on bone morphogenetic protein (BMP) and its carriers performed using the critical sized segmental defect (CSD) model in rat fibula and to investigate development of animal models and carriers for more effective bone regeneration. Materials and Methods For the experiments, 14, 16, and 24 rats with CSDs on both fibulae were used in Experiments 1, 2, and 3, respectively. BMP-2 with absorbable collagen sponge (ACS) (Experiments 1 and 2), autoclaved autogenous bone (AAB) and fibrin glue (FG) (Experiment 3), and xenogenic bone (Experiment 2) were used in the experimental groups. Radiographic and histomorphological evaluations were performed during the follow-up period of each experiment. Results Significant new bone formation was commonly observed in all experimental groups using BMP-2 compared to control and xenograft (porcine bone) groups. Although there was some difference based on BMP carrier, regenerated bone volume was typically reduced by remodeling after initially forming excessive bone. Conclusion BMP-2 demonstrates excellent ability for bone regeneration because of its osteoinductivity, but efficacy can be significantly different depending on its delivery system. ACS and FG showed relatively good bone regeneration capacity, satisfying the essential conditions of localization and release-control when used as BMP carriers. AAB could not provide release-control as a BMP carrier, but its space-maintenance role was remarkable. Carriers and scaffolds that can provide sufficient support to the BMP/carrier complex are necessary for large bone defects, and AAB is thought to be able to act as an effective scaffold. The CSD model of rat fibula is simple and useful for initial estimate of bone regeneration by agents including BMPs. PMID:29333367

  19. Silibinin promotes osteoblast differentiation of human bone marrow stromal cells via bone morphogenetic protein signaling.

    PubMed

    Ying, Xiaozhou; Sun, Liaojun; Chen, Xiaowei; Xu, Huazi; Guo, Xiaoshan; Chen, Hua; Hong, Jianjun; Cheng, Shaowen; Peng, Lei

    2013-12-05

    Silibinin is the major active constituent of the natural compound silymarin; several studies suggest that silibinin possesses antihepatotoxic properties and anticancer effects against carcinoma cells. However, no study has yet investigated the effect of silibinin on osteogenic differentiation of human bone marrow stem cells (hBMSCs). The aim of this study was to evaluate the effect of silibinin on osteogenic differentiation of hBMSCs. In this study, the hBMSCs were cultured in an osteogenic medium with 0, 1, 10 or 20 μmol/l silibinin respectively. hBMSCs viability was analyzed by cell number quantification assay and cells osteogenic differentiation was evaluated by alkaline phosphatas (ALP) activity assay, Von Kossa staining and real time-polymerase chain reaction (RT-PCR). We found that silibinin promoted ALP activity in hBMSCs without affecting their proliferation. The mineralization of hBMSCs was enhanced by treatment with silibinin. Silibinin also increased the mRNA expressions of Collagen type I (COL-I), ALP, Osteocalcin (OCN), Osterix, bone morphogenetic protein-2 (BMP-2) and Runt-related transcription factor 2 (RUNX2). The BMP antagonist noggin and its receptor kinase inhibitors dorsomorphin and LDN-193189 attenuated silibinin-promoted ALP activity. Furthermore, BMP-responsive and Runx2-responsive reporters were activated by silibinin treatment. These results indicate that silibinin enhances osteoblast differentiation probably by inducing the expressions of BMPs and activating BMP and RUNX2 pathways. Thus, silibinin may play an important therapeutic role in osteoporosis patients by improving osteogenic differentiation of BMSCs. © 2013 Elsevier B.V. All rights reserved.

  20. Novel Therapy for Bone Regeneration in Large Segmental Defects

    DTIC Science & Technology

    2017-12-01

    HC, Giannoudis PV. Fat embolism and IM nailing. Injury. 2006;37(Suppl 4):S1–2. 38. Wenda K, Ritter G, Degreif J, Rudigier J. Pathogenesis of pul...morphogenetic protein (BMP), thrombopoietin (TPO), therapy, fracture healing, bone regeneration, minipig, pig 16. SECURITY CLASSIFICATION OF: 17... fracture healing, bone regeneration, minipig, pig 3. OVERALL PROJECT SUMMARY: Project start date 30/09/2013 Project end date 29/09/2017 (with 1 year NCE

  1. Low-intensity pulsed ultrasound produced an increase of osteogenic genes expression during the process of bone healing in rats.

    PubMed

    Fávaro-Pípi, Elaine; Bossini, Paulo; de Oliveira, Poliani; Ribeiro, Juliana Uema; Tim, Carla; Parizotto, Nivaldo A; Alves, Jose Marcos; Ribeiro, Daniel Araki; Selistre de Araújo, Heloísa Sobreiro; Renno, Ana Claudia Muniz

    2010-12-01

    The aim of this study was to measure the temporal expression of osteogenic genes during the process of bone healing in low-intensity pulsed ultrasound (LIPUS) treated bone defects by means of histopathologic and real-time polymerase chain reaction (PCR) analysis. Animals were randomly distributed into two groups (n = 30): control group (bone defect without treatment) and LIPUS treated (bone defect treated with LIPUS). On days 7, 13 and 25 postinjury, 10 rats per group were sacrificed. Rats were treated with a 30 mW/cm(2) LIPUS. The results pointed out intense new bone formation surrounded by highly vascularized connective tissue presenting a slight osteogenic activity, with primary bone deposition was observed in the group exposed to LIPUS in the intermediary (13 days) and late stages of repair (25 days) in the treated animals. In addition, quantitative real-time polymerase chain reaction (RT-qPCR) showed an upregulation of bone morphogenetic protein 4 (BMP4), osteocalcin and Runx2 genes 7 days after the surgery. In the intermediary period, there was no increase in the expression. The expression of alkaline phosphatase, BMP4 and Runx2 was significantly increased at the last period. Our results indicate that LIPUS therapy improves bone repair in rats and upregulated osteogenic genes, mainly at the late stages of recovery. Copyright © 2010. Published by Elsevier Inc.

  2. Combined sustained release of BMP2 and MMP10 accelerates bone formation and mineralization of calvaria critical size defect in mice.

    PubMed

    Reyes, Ricardo; Rodríguez, Jose Antonio; Orbe, Josune; Arnau, María Rosa; Évora, Carmen; Delgado, Araceli

    2018-11-01

    The effect of dual delivery of bone morphogenetic protein-2 (BMP-2) and matrix metalloproteinase 10 (MMP10) on bone regeneration was investigated in a murine model of calvarial critical-size defect, hypothesizing that it would result in an enhanced bone formation. Critical-size calvarial defects (4 mm diameter) were created in mice and PLGA microspheres preloaded with either BMP-2, MMP10 or a microsphere combination of both were transplanted into defect sites at different doses. Empty microspheres were used as the negative control. Encapsulation efficiency was assessed and in vivo release kinetics of BMP-2 and MMP10 were examined over 14 days. Histological analyses were used to analyze bone formation after four and eight weeks. Combination with MMP10 (30 ng) significantly enhanced BMP-2 (600 ng)-mediated osteogenesis, as confirmed by the increase in percentage of bone fill (p < .05) at four weeks. Moreover, it also increased mineral apposition rate (p < .05), measured by double labeling with tetracycline and calceine. MMP10 accelerates bone repair by enhancing BMP-2-promoted bone healing and improving the mineralization rate. In conclusion combination of MMP10 and BMP-2 may become a promising strategy for repair and regeneration of bone defects.

  3. Biomimetic coatings for bone tissue engineering of critical-sized defects.

    PubMed

    Liu, Yuelian; Wu, Gang; de Groot, Klaas

    2010-10-06

    The repair of critical-sized bone defects is still challenging in the fields of implantology, maxillofacial surgery and orthopaedics. Current therapies such as autografts and allografts are associated with various limitations. Cytokine-based bone tissue engineering has been attracting increasing attention. Bone-inducing agents have been locally injected to stimulate the native bone-formation activity, but without much success. The reason is that these drugs must be delivered slowly and at a low concentration to be effective. This then mimics the natural method of cytokine release. For this purpose, a suitable vehicle was developed, the so-called biomimetic coating, which can be deposited on metal implants as well as on biomaterials. Materials that are currently used to fill bony defects cannot by themselves trigger bone formation. Therefore, biological functionalization of such materials by the biomimetic method resulted in a novel biomimetic coating onto different biomaterials. Bone morphogenetic protein 2 (BMP-2)-incorporated biomimetic coating can be a solution for a large bone defect repair in the fields of dental implantology, maxillofacial surgery and orthopaedics. Here, we review the performance of the biomimetic coating both in vitro and in vivo.

  4. Influence of bone morphogenetic protein and proportion of hydroxyapatite on new bone formation in biphasic calcium phosphate graft: two pilot studies in animal bony defect model.

    PubMed

    Yun, Pil-Young; Kim, Young-Kyun; Jeong, Kyung-In; Park, Ju-Cheol; Choi, Yeon-Jo

    2014-12-01

    The purpose of these two pilot studies using animal bony defect models was to evaluate the influence of bone morphogenetic protein (BMP) and proportion of hydroxyapatite (HA)/beta-tricalcium phosphate (β-TCP) in biphasic calcium phosphate (BCP) graft on new bone formation. In this study, four kinds of synthetic osteoconductive bone materials known for bone growth scaffold, OSTEON™II(HA:β-TCP 30:70), OSTEON™III (HA:β-TCP 20:80), OSTEON™II Collagen, and OSTEON™III Collagen, were prepared as BCP graft materials. In pilot study 1, three BCP materials (OSTEON™II, OSTEON™III, and OSTEON™II Collagen) were grafted in rabbit calvarial defects after impregnating in rhBMP-2. OSTEON™II without the rhBMP-2 impregnation was included in the study as the control. The amount of new bone was examined and measured histologically at 2, 4, and 8 weeks. In pilot study 2, four BCP materials (OSTEON™II, OSTEON™III, OSTEON™II Collagen, and OSTEON™III Collagen) were grafted in beagle dog mandibular defects after soaking in the rhBMP-2. The amount of total bone and new bone were measured three-dimensionally using microCT and healing process was examined histologically at 2, 4, and 8 weeks. In pilot study 1, rhBMP-2 impregnated groups showed more new bone formation than the rhBMP-2 free group. In pilot study 2, increased new bone formation was observed in time-dependent manner after graft of BCP and BCP-collagen (OSTEON™II, OSTEON™III, OSTEON™II Collagen, and OSTEON™III Collagen) impregnated with rhBMP-2. Also, BCP with a higher proportion of HA (30% HA) showed more favorable result in new bone formation and space maintenance, especially at the 8 weeks. From the results of the pilot studies, rhBMP-2 played positive roles in new bone formation and BCP could become a scaffold candidate for rhBMP-2 impregnation to induce new bone formation. Moreover, BCP with a higher proportion of HA (30% HA) could be considered more appropriate for rhBMP-2 carrier. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  5. Dose reduction of bone morphogenetic protein-2 for bone regeneration using a delivery system based on lyophilization with trehalose.

    PubMed

    Zhang, Xiaochen; Yu, Quan; Wang, Yan-An; Zhao, Jun

    2018-01-01

    To induce sufficient new bone formation, high doses of bone morphogenetic protein-2 (BMP-2) are applied in regenerative medicine that often induce serious side effects. Therefore, improved treatment strategies are required. Here, we investigate whether the delivery of BMP-2 lyophilized in the presence of trehalose reduced the dose of BMP-2 required for bone regeneration. A new growth factor delivery system was fabricated using BMP-2-loaded TiO 2 nanotubes by lyophilization with trehalose (TiO 2 -Lyo-Tre-BMP-2). We measured BMP-2 release characteristics, bioactivity, and stability, and determined the effects on the osteogenic differentiation of bone marrow stromal cells in vitro. Additionally, we evaluated the ability of this formulation to regenerate new bone around implants in rat femur defects by micro-computed tomography (micro-CT), sequential fluorescent labelling, and histological analysis. Compared with absorbed BMP-2-loaded TiO 2 nanotubes (TiO 2 -BMP-2), TiO 2 -Lyo-Tre-BMP-2 exhibited sustained release, consistent bioactivity, and higher stability of BMP-2, and resulted in greater osteogenic differentiation of BMSCs. Eight weeks post-operation, TiO 2 -Lyo-Tre-BMP-2 nanotubes, with various dosages of BMP-2, regenerated larger amounts of new bone than TiO 2 -BMP-2 nanotubes. Our findings indicate that delivery of BMP-2 lyophilized with trehalose may be a promising method to reduce the dose of BMP-2 and avoid the associated side effects.

  6. Negative effect of serotonin-norepinephrine reuptake inhibitor therapy on rat bone tissue after orchidectomy.

    PubMed

    Fekete, Sona; Simko, Julius; Mzik, Martin; Karesova, Iva; Zivna, Helena; Zivny, Pavel; Pavliková, Ladislava; Palicka, Vladimir

    2015-08-15

    Our goal was to determine if venlafaxine has a negative effect on bone metabolism. Rats were divided into three groups. The sham-operated control group (SHAM), the control group after orchidectomy (ORX), and the experimental group after orchidectomy received venlafaxine (VEN ORX) in standard laboratory diet (SLD) for 12 weeks. Bone mineral content (BMC) was measured by dual energy X-ray absorptiometry (DXA). Bone marker concentrations of carboxy-terminal cross-linking telopeptide of type I collagen (CTX-I), osteoprotegerin (OPG), amino-terminal propeptide of procollagen type I (P1NP), bone alkaline phosphatase (BALP), sclerostin and bone morphogenetic protein 2 (BMP-2) were examined in bone homogenate. The femurs were used for biomechanical testing. Compared to the ORX group we found lower BMD in the diaphysis area of the femur in the VEN ORX group, suggesting a preferential effect on cortical bone. Of the bone metabolism markers, there was significant decrease (ORX control group versus VEN ORX experimental group) in BALP levels and increase in sclerostin and CTX-I levels, suggesting a decrease in osteoid synthesis and increased bone resorption. The results suggest that the prolonged use of venlafaxine may have a negative effect on bone metabolism. Further studies are warranted to establish whether venlafaxine may have a clinically significant adverse effect on bone. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Heterotopic ossification after the use of recombinant human bone morphogenetic protein-7

    PubMed Central

    Papanagiotou, Marianthi; Dailiana, Zoe H; Karachalios, Theophilos; Varitimidis, Sokratis; Hantes, Michael; Dimakopoulos, Georgios; Vlychou, Marianna; Malizos, Konstantinos N

    2017-01-01

    AIM To present the incidence of heterotopic ossification after the use of recombinant human bone morphogenetic protein-7 (rhBMP-7) for the treatment of nonunions. METHODS Bone morphogenetic proteins (BMPs) promote bone formation by auto-induction. Recombinant human BMP-7 in combination with bone grafts was used in 84 patients for the treatment of long bone nonunions. All patients were evaluated radiographicaly for the development of heterotopic ossification during the standard assessment for the nonunion healing. In all patients (80.9%) with radiographic signs of heterotopic ossification, a CT scan was performed. Nonunion site palpation and ROM evaluation of the adjacent joints were also carried out. Factors related to the patient (age, gender), the nonunion (location, size, chronicity, number of previous procedures, infection, surrounding tissues condition) and the surgical procedure (graft and fixation type, amount of rhBMP-7) were correlated with the development of heterotopic ossification and statistical analysis with Pearsons χ2 test was performed. RESULTS Eighty point nine percent of the nonunions treated with rhBMP-7, healed with no need for further procedures. Heterotopic bone formation occurred in 15 of 84 patients (17.8%) and it was apparent in the routine radiological evaluation of the nonunion site, in a mean time of 5.5 mo after the rhBMP-7 application (range 3-12). The heterotopic ossification was located at the femur in 8 cases, at the tibia in 6, and at the humerus in οne patient. In 4 patients a palpable mass was present and only in one patient, with a para-articular knee nonunion treated with rhBMP-7, the size of heterotopic ossification affected the knee range of motion. All the patients with heterotopic ossification were male. Statistical analysis proved that patient’s gender was the only important factor for the development of heterotopic ossification (P = 0.007). CONCLUSION Heterotopic ossification after the use of rhBMP-7 in nonunions was common but it did not compromise the final clinical outcome in most cases, and affected only male patients. PMID:28144577

  8. A myostatin and activin decoy receptor enhances bone formation in mice.

    PubMed

    Bialek, P; Parkington, J; Li, X; Gavin, D; Wallace, C; Zhang, J; Root, A; Yan, G; Warner, L; Seeherman, H J; Yaworsky, P J

    2014-03-01

    Myostatin is a member of the bone morphogenetic protein/transforming growth factor-β (BMP/TGFβ) super-family of secreted differentiation factors. Myostatin is a negative regulator of muscle mass as shown by increased muscle mass in myostatin deficient mice. Interestingly, these mice also exhibit increased bone mass suggesting that myostatin may also play a role in regulating bone mass. To investigate the role of myostatin in bone, young adult mice were administered with either a myostatin neutralizing antibody (Mstn-mAb), a soluble myostatin decoy receptor (ActRIIB-Fc) or vehicle. While both myostatin inhibitors increased muscle mass, only ActRIIB-Fc increased bone mass. Bone volume fraction (BV/TV), as determined by microCT, was increased by 132% and 27% in the distal femur and lumbar vertebrae, respectively. Histological evaluation demonstrated that increased BV/TV in both locations was attributed to increased trabecular thickness, trabecular number and bone formation rate. Increased BV/TV resulted in enhanced vertebral maximum compressive force compared to untreated animals. The fact that ActRIIB-Fc, but not Mstn-mAb, increased bone volume suggested that this soluble decoy receptor may be binding a ligand other than myostatin, that plays a role in regulating bone mass. This was confirmed by the significant increase in BV/TV in myostatin deficient mice treated with ActRIIB-Fc. Of the other known ActRIIB-Fc ligands, BMP3 has been identified as a negative regulator of bone mass. However, BMP3 deficient mice treated with ActRIIB-Fc showed similar increases in BV/TV as wild type (WT) littermates treated with ActRIIB-Fc. This result suggests that BMP3 neutralization is not the mechanism responsible for increased bone mass. The results of this study demonstrate that ActRIIB-Fc increases both muscle and bone mass in mice. Therefore, a therapeutic that has this dual activity represents a potential approach for the treatment of frailty. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Salicylic Acid-Based Polymers for Guided Bone Regeneration Using Bone Morphogenetic Protein-2

    PubMed Central

    Subramanian, Sangeeta; Mitchell, Ashley; Yu, Weiling; Snyder, Sabrina; Uhrich, Kathryn

    2015-01-01

    Bone morphogenetic protein-2 (BMP-2) is used clinically to promote spinal fusion, treat complex tibia fractures, and to promote bone formation in craniomaxillofacial surgery. Excessive bone formation at sites where BMP-2 has been applied is an established complication and one that could be corrected by guided tissue regeneration methods. In this study, anti-inflammatory polymers containing salicylic acid [salicylic acid-based poly(anhydride-ester), SAPAE] were electrospun with polycaprolactone (PCL) to create thin flexible matrices for use as guided bone regeneration membranes. SAPAE polymers hydrolyze to release salicylic acid, which is a nonsteroidal anti-inflammatory drug. PCL was used to enhance the mechanical integrity of the matrices. Two different SAPAE-containing membranes were produced and compared: fast-degrading (FD-SAPAE) and slow-degrading (SD-SAPAE) membranes that release salicylic acid at a faster and slower rate, respectively. Rat femur defects were treated with BMP-2 and wrapped with FD-SAPAE, SD-SAPAE, or PCL membrane or were left unwrapped. The effects of different membranes on bone formation within and outside of the femur defects were measured by histomorphometry and microcomputed tomography. Bone formation within the defect was not affected by membrane wrapping at BMP-2 doses of 12 μg or more. In contrast, the FD-SAPAE membrane significantly reduced bone formation outside the defect compared with all other treatments. The rapid release of salicylic acid from the FD-SAPAE membrane suggests that localized salicylic acid treatment during the first few days of BMP-2 treatment can limit ectopic bone formation. The data support development of SAPAE polymer membranes for guided bone regeneration applications as well as barriers to excessive bone formation. PMID:25813520

  10. Bone formation at recombinant human bone morphogenetic protein-2-coated titanium implants in the posterior mandible (Type II bone) in dogs.

    PubMed

    Wikesjö, Ulf M E; Xiropaidis, Andreas V; Qahash, Mohammed; Lim, Won Hee; Sorensen, Rachel G; Rohrer, Michael D; Wozney, John M; Hall, Jan

    2008-11-01

    Conventional oral/maxillofacial implants reach osseointegration over several months during which the titanium fixtures interact with alveolar bone. The objective of this study was to determine if adsorbing recombinant human bone morphogenetic protein-2 (rhBMP-2) onto a titanium porous oxide (TPO) implant surface might enhance or accelerate local bone formation and support osseointegration in a large animal oral/maxillofacial orthotopic model. Endosseous implants with a TPO surface were installed into the edentulated posterior mandible in eight adult Hound Labrador mongrel dogs. The implant surface had been adsorbed with rhBMP-2 at 0.2 or 4.0 mg/ml. TPO implants without rhBMP-2 served as control. Treatments were randomized between jaw quadrants. Mucosal flaps were advanced and sutured leaving the implants submerged. Clinical and radiographic evaluations were made immediately post-surgery, at day 10 (suture removal), and week 4 and 8 post-surgery. The animals received fluorescent bone markers at week 3, 4, and at week 8 post-surgery, when they were euthanized for histologic analysis. TPO implants coated with rhBMP-2 exhibited dose-dependent bone remodelling including immediate resorption and formation of implant adjacent bone, and early establishment of clinically relevant osseointegration. The resulting bone-implant contact, although clinically respectable, appeared significantly lower for rhBMP-2-coated implants compared with the control [rhBMP-2 (0.2 mg/ml) 43.3+/-10.8%versus 71.7+/-7.8%, p<0.02; rhBMP-2 (4.0 mg/ml) 35.4+/-10.6%versus 68.2+/-11.0%, p<0.03]. rhBMP-2 adsorbed onto TPO implant surfaces initiates dose-dependent peri-implant bone re-modelling resulting in the formation of normal, physiologic bone and clinically relevant osseointegration within 8 weeks.

  11. Canola and hydrogenated soybean oils accelerate ectopic bone formation induced by implantation of bone morphogenetic protein in mice.

    PubMed

    Hashimoto, Yoko; Mori, Mayumi; Kobayashi, Shuichiro; Hanya, Akira; Watanabe, Shin-Ichi; Ohara, Naoki; Noguchi, Toshihide; Kawai, Tatsushi; Okuyama, Harumi

    2014-01-01

    Canola oil (Can) and hydrogenated soybean oil (H2-Soy) are commonly used edible oils. However, in contrast to soybean oil (Soy), they shorten the survival of stroke-prone spontaneously hypertensive (SHRSP) rats. It has been proposed that the adverse effects of these oils on the kidney and testis are caused at least in part by dihydro-vitamin K (VK) 1 in H2-Soy and unidentified component(s) in Can. Increased intake of dihydro-VK1 is associated with decreased tissue VK2 levels and bone mineral density in rats and humans, respectively. The aim of the present study was to determine the effects of these oils on bone morphogenetic protein (BMP)-induced ectopic bone formation, which is promoted by VK2 deficiency, in relation to the role of VK in the γ-carboxylation of osteocalcin and matrix Gla protein. A crude extract of BMPs was implanted into a gap in the fascia of the femoral muscle in 5-week-old mice maintained on a Soy, Can, or H2-Soy diet. Newly formed bone volume, assessed by three-dimensional X-ray micro-computed tomography and three-dimensional reconstruction imaging for bone, was 4-fold greater in the Can and H2-Soy groups than in the Soy group. The plasma carboxylated osteocalcin (Gla-OC) and total OC (Gla-OC plus undercarboxylated osteocalcin [Glu-OC]) levels were significantly lower in the Can group than in the Soy group ( p < 0.05). However, these levels did not significantly differ between the H2-Soy and Soy groups. The plasma Gla-OC/Glu-OC ratio in the Can and H2-Soy groups was significantly lower (in Can; p = 0.044) or was almost significantly lower (in H2-Soy; p = 0.053) than that in the Soy group. In conclusion, Can and H2-Soy accelerated BMP-induced bone formation in mice to a greater extent than Soy. Further research is required to evaluate whether the difference in accelerated ectopic bone formation is associated with altered levels of VK2 and VK-dependent protein(s) among the three dietary groups.

  12. Complications of Anterior Cervical Fusion using a Low-dose Recombinant Human Bone Morphogenetic Protein-2

    PubMed Central

    Kukreja, Sunil; Ahmed, Osama I; Haydel, Justin; Nanda, Anil

    2015-01-01

    Objective There are several reports, which documented a high incidence of complications following the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) in anterior cervical fusions (ACFs). The objective of this study is to share our experience with low-dose rhBMP-2 in anterior cervical spine. Methods We performed a retrospective analysis of 197 patients who underwent anterior cervical fusion (ACF) with the use of recombinant human bone morphogenetic protein-2 (rhBMP-2) during 2007-2012. A low-dose rhBMP-2 (0.7mg/level) sponge was placed exclusively within the cage. In 102 patients demineralized bone matrix (DBM) was filled around the BMP sponge. Incidence and severity of dysphagia was determined by 5 points SWAL-QOL scale. Results Two patients had prolonged hospitalization due to BMP unrelated causes. Following the discharge, 13.2%(n=26) patients developed dysphagia and 8.6%(n=17) patients complained of neck swelling. More than half of the patients (52.9%, n=9) with neck swelling also had associated dysphagia; however, only 2 of these patients necessitated readmission. Both of these patients responded well to the intravenous dexamethasone. The use of DBM did not affect the incidence and severity of complications (p>0.05). Clinico-radiological evidence of fusion was not observed in 2 patients. Conclusion A low-dose rhBMP-2 in ACFs is not without risk. However, the incidence and severity of complications seem to be lower with low-dose BMP placed exclusively inside the cage. Packing DBM putty around the BMP sponge does not affect the safety profile of rhBMP-2 in ACFs. PMID:26217385

  13. Effects of recombinant human bone morphogenetic protein 7 (rhBMP-7) on the behaviour of oral squamous cell carcinoma: a preliminary in vitro study.

    PubMed

    Lappin, D F; Abu-Serriah, M; Hunter, K D

    2015-02-01

    We investigated the effects of recombinant human bone morphogenetic protein-7 (rhBMP-7) on the behaviour of oral keratinocytes and head and neck squamous cell carcinoma (SCC) cells in vitro. Expression of all three BMP receptors was high (p<0.01), and rhBMP-7 exhibited significant dose-related inhibitory effects on the doubling time and viability of cancer cells (p<0.01), but not on the proliferation or viability of oral keratinocytes. It elicited no significant effect on the invasion of Matrigel in SCC of the head and neck. Results indicate that in cell culture, rhBMP-7 exerts antineoplastic effects. This should be tested in an orthotopic animal model to more closely replicate in vivo effects. Copyright © 2014. Published by Elsevier Ltd.

  14. Smad7 Regulates the Adult Neural Stem/Progenitor Cell Pool in a Transforming Growth Factor β- and Bone Morphogenetic Protein-Independent Manner▿

    PubMed Central

    Krampert, Monika; Chirasani, Sridhar Reddy; Wachs, Frank-Peter; Aigner, Robert; Bogdahn, Ulrich; Yingling, Jonathan M.; Heldin, Carl-Henrik; Aigner, Ludwig; Heuchel, Rainer

    2010-01-01

    Members of the transforming growth factor β (TGF-β) family of proteins modulate the proliferation, differentiation, and survival of many different cell types. Neural stem and progenitor cells (NPCs) in the adult brain are inhibited in their proliferation by TGF-β and by bone morphogenetic proteins (BMPs). Here, we investigated neurogenesis in a hypomorphic mouse model for the TGF-β and BMP inhibitor Smad7, with the hypothesis that NPC proliferation might be reduced due to increased TGF-β and BMP signaling. Unexpectedly, we found enhanced NPC proliferation as well as an increased number of label-retaining cells in vivo. The enhanced proliferation potential of mutant cells was retained in vitro in neurosphere cultures. We observed a higher sphere-forming capacity as well as faster growth and cell cycle progression. Use of specific inhibitors revealed that these effects were independent of TGF-β and BMP signaling. The enhanced proliferation might be at least partially mediated by elevated signaling via epidermal growth factor (EGF) receptor, as mutant cells showed higher expression and activation levels of the EGF receptor. Conversely, an EGF receptor inhibitor reduced the proliferation of these cells. Our data indicate that endogenous Smad7 regulates neural stem/progenitor cell proliferation in a TGF-β- and BMP-independent manner. PMID:20479122

  15. Bone Morphogenetic Protein 4 Promotes Vascular Smooth Muscle Contractility by Activating MicroRNA-21 (miR-21), which Down-regulates Expression of Family of Dedicator of Cytokinesis (DOCK) Proteins*

    PubMed Central

    Kang, Hara; Davis-Dusenbery, Brandi N.; Nguyen, Peter H.; Lal, Ashish; Lieberman, Judy; Van Aelst, Linda; Lagna, Giorgio; Hata, Akiko

    2012-01-01

    The bone morphogenetic protein 4 (BMP4) signaling pathway plays a critical role in the promotion and maintenance of the contractile phenotype in vascular smooth muscle cell (vSMC). Misexpression or inactivating mutations of the BMP receptor gene can lead to dedifferentiation of vSMC characterized by increased migration and proliferation that is linked to vascular proliferative disorders. Previously we demonstrated that vSMCs increase microRNA-21 (miR-21) biogenesis upon BMP4 treatment, which induces contractile gene expression by targeting programmed cell death 4 (PDCD4). To identify novel targets of miR-21 that are critical for induction of the contractile phenotype by BMP4, biotinylated miR-21 was expressed in vSMCs followed by an affinity purification of mRNAs associated with miR-21. Nearly all members of the dedicator of cytokinesis (DOCK) 180-related protein superfamily were identified as targets of miR-21. Down-regulation of DOCK4, -5, and -7 by miR-21 inhibited cell migration and promoted cytoskeletal organization by modulating an activity of small GTPase. Thus, this study uncovers a regulatory mechanism of the vSMC phenotype by the BMP4-miR-21 axis through DOCK family proteins. PMID:22158624

  16. Selective inhibitors of the osteoblast proteasome stimulate bone formation in vivo and in vitro

    PubMed Central

    Garrett, I.R.; Chen, D.; Gutierrez, G.; Zhao, M.; Escobedo, A.; Rossini, G.; Harris, S.E.; Gallwitz, W.; Kim, K.B.; Hu, S.; Crews, C.M.; Mundy, G.R.

    2003-01-01

    We have found that the ubiquitin-proteasome pathway exerts exquisite control of osteoblast differentiation and bone formation in vitro and in vivo in rodents. Structurally different inhibitors that bind to specific catalytic β subunits of the 20S proteasome stimulated bone formation in bone organ cultures in concentrations as low as 10 nM. When administered systemically to mice, the proteasome inhibitors epoxomicin and proteasome inhibitor–1 increased bone volume and bone formation rates over 70% after only 5 days of treatment. Since the ubiquitin-proteasome pathway has been shown to modulate expression of the Drosophila homologue of the bone morphogenetic protein-2 and -4 (BMP-2 and BMP-4) genes, we examined the effects of noggin, an endogenous inhibitor of BMP-2 and BMP-4 on bone formation stimulated by these compounds and found that it was abrogated. These compounds increased BMP-2 but not BMP-4 or BMP-6 mRNA expression in osteoblastic cells, suggesting that BMP-2 was responsible for the observed bone formation that was inhibited by noggin. We show proteasome inhibitors regulate BMP-2 gene expression at least in part through inhibiting the proteolytic processing of Gli3 protein. Our results suggest that the ubiquitin-proteasome machinery regulates osteoblast differentiation and bone formation and that inhibition of specific components of this system may be useful therapeutically in common diseases of bone loss. PMID:12782679

  17. Gene Therapy of Bone Morphogenetic Protein for Periodontal Tissue Engineering

    PubMed Central

    Jin, Q-M.; Anusaksathien, O.; Webb, S.A.; Rutherford, R.B.; Giannobile, W.V.

    2009-01-01

    Background The reconstruction of lost periodontal support including bone, ligament, and cementum is a major goal of therapy. Bone morphogenetic proteins (BMPs) have shown much potential in the regeneration of the periodontium. Limitations of BMP administration to periodontal lesions include need for high-dose bolus delivery, BMP transient biological activity, and low bioavailability of factors at the wound site. Gene transfer offers promise as an alternative treatment strategy to deliver BMPs to periodontal tissues. Methods This study utilized ex vivo BMP-7 gene transfer to stimulate tissue engineering of alveolar bone wounds. Syngeneic dermal fibroblasts (SDFs) were transduced ex vivo with adenoviruses encoding either green fluorescent protein (Ad-GFP or control virus), BMP-7 (Ad-BMP-7), or an antagonist of BMP bioactivity, noggin (Ad-noggin). Transduced cells were seeded onto gelatin carriers and then transplanted to large mandibular alveolar bone defects in a rat wound repair model. Results Ad-noggin treatment tended to inhibit osteogenesis as compared to the control-treated and Ad-BMP-7-treated specimens. The osseous lesions treated by Ad-BMP-7 gene delivery demonstrated rapid chrondrogenesis, with subsequent osteogenesis, cementogenesis and predictable bridging of the periodontal bone defects. Conclusion These results demonstrate the first successful evidence of periodontal tissue engineering using ex vivo gene transfer of BMPs and offers a new approach for repairing periodontal defects. PMID:12666709

  18. Digital subtraction radiographic analysis of the combination of bioabsorbable membrane and bovine morphogenetic protein pool in human periodontal infrabony defects

    PubMed Central

    GUIMARÃES, Maria do Carmo Machado; PASSANEZI, Euloir; SANT’ANA, Adriana Campos Passanezi; GREGHI, Sebastião Luiz Aguiar; TABA JUNIOR, Mario

    2010-01-01

    Objectives This study assessed the bone density gain and its relationship with the periodontal clinical parameters in a case series of a regenerative therapy procedure. Material and Methods Using a split-mouth study design, 10 pairs of infrabony defects from 15 patients were treated with a pool of bovine bone morphogenetic proteins associated with collagen membrane (test sites) or collagen membrane only (control sites). The periodontal healing was clinically and radiographically monitored for six months. Standardized presurgical and 6-month postoperative radiographs were digitized for digital subtraction analysis, which showed relative bone density gain in both groups of 0.034 ± 0.423 and 0.105 ± 0.423 in the test and control group, respectively (p>0.05). Results As regards the area size of bone density change, the influence of the therapy was detected in 2.5 mm2 in the test group and 2 mm2 in the control group (p>0.05). Additionally, no correlation was observed between the favorable clinical results and the bone density gain measured by digital subtraction radiography (p>0.05). Conclusions The findings of this study suggest that the clinical benefit of the regenerative therapy observed did not come with significant bone density gains. Long-term evaluation may lead to a different conclusions. PMID:20835573

  19. Interplay between self-assembled structure of bone morphogenetic protein-2 (BMP-2) and osteoblast functions in three-dimensional titanium alloy scaffolds: Stimulation of osteogenic activity.

    PubMed

    Nune, K C; Kumar, A; Murr, L E; Misra, R D K

    2016-02-01

    Three-dimensional cellular scaffolds are receiving significant attention in bone tissue engineering to treat segmental bone defects. However, there are indications of lack of significant osteoinductive ability of three-dimensional cellular scaffolds. In this regard, the objective of the study is to elucidate the interplay between bone morphogenetic protein (BMP-2) and osteoblast functions on 3D mesh structures with different porosities and pore size that were fabricated by electron beam melting. Self-assembled dendritic microstructure with interconnected cellular-type morphology of BMP-2 on 3D scaffolds stimulated osteoblast functions including adhesion, proliferation, and mineralization, with prominent effect on 2-mm mesh. Furthermore, immunofluorescence studies demonstrated higher density and viability of osteoblasts on lower porosity mesh structure (2 mm) as compared to 3- and 4-mm mesh structures. Enhanced filopodia cellular extensions with extensive cell spreading was observed on BMP-2 treated mesh structures, a behavior that is attributed to the unique self-assembled structure of BMP-2 that effectively communicates with the cells. The study underscores the potential of BMP-2 in imparting osteoinductive capability to the 3D printed scaffolds. © 2015 Wiley Periodicals, Inc.

  20. Localized bone regeneration around dental implants using recombinant bone morphogenetic protein-2 and platelet-derived growth factor-BB in the canine.

    PubMed

    Thoma, Daniel S; Cha, Jae-Kook; Sapata, Vitor M; Jung, Ronald E; Hüsler, Juerg; Jung, Ui-Won

    2017-11-01

    To test whether or not one of two biological mediators (recombinant human bone morphogenetic protein-2 (rhBMP-2) and recombinant human platelet-derived growth factor (rhPDGF-BB)) is superior to the other and compared with control groups for bone regeneration around implants based on histomorphometrical outcome measures. Box-type defects (10 × 5 × 5 mm) were prepared on the buccal sides of the left and right edentulous ridge in ten mongrel dogs. Implants were placed at each site, the defects either received (i) bovine-derived particulated bone mineral (DBBM) mixed with rhBMP-2 and a collagen membrane (CM) (DBBM/BMP-2), (ii) DBBM mixed with rhPDGF-BB and CM (DBBM/PDGF), (iii) DBBM and CM (DBBM) and (iv) empty control (control). Animals were euthanized post-surgery at 8 weeks and 16 weeks. Histomorphometrical analyses were performed. The mean percentages of regenerated area within total defect area amounted to 56.95% for DBBM/BMP-2, 48.86% for DBBM/PDFG, 33.44% for DBBM and 1.59% for control at 8 weeks, and 26.79% for DBBM/BMP-2, 23.78% for DBBM/PDFG, 30.21% for DBBM and 5.07% for control at 16 weeks with no statistically significant differences between the groups (P > 0.05). The mean amount of regenerated bone was 26.97% for DBBM/BMP-2, 22.02% for DBBM/PDFG, 5.03% for DBBM and 1.25% for control at 8 weeks, and at 16 weeks, these values were lower in the two groups with biological mediators (DBBM/BMP-2 = 13.35%; DBBM/PDGF = 6.96%) and only slightly increased in group DBBM (10.68%) and the control group (4.95%) compared with 8 weeks. The first bone-to-implant contact values on the buccal side were minimal for DBBM/BMP-2 (0.57 mm) and maximal for control (3.72 mm) at 8 weeks. The use of biological mediators (rhBMP-2 and rhPDGF-BB) can increase the amount of bone regeneration at dehiscence-type defects compared with controls at 8 weeks, but not at 16 weeks due to enhanced hard tissue remodeling processes. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Overexpression of BMP3 in the developing skeleton alters endochondral bone formation resulting in spontaneous rib fractures.

    PubMed

    Gamer, Laura W; Cox, Karen; Carlo, Joelle M; Rosen, Vicki

    2009-09-01

    Bone morphogenetic protein-3 (BMP) has been identified as a negative regulator in the skeleton as mice lacking BMP3 have increased bone mass. To further understand how BMP3 mediates bone formation, we created transgenic mice overexpressing BMP3 using the type I collagen promoter. BMP3 transgenic mice displayed spontaneous rib fractures that were first detected at E17.0. The fractures were due to defects in differentiation of the periosteum and late hypertrophic chondrocytes resulting in thinner cortical bone with decreased mineralization. As BMP3 modulates BMP and activin signaling through ActRIIB, we examined the ribs of ActRIIB receptor knockout mice and found they had defects in late chondrogenesis and mineralization similar to BMP3 transgenic mice. These data suggest that BMP3 exerts its effects in the skeleton by altering signaling through ActRIIB in chondrocytes and the periosteum, and this results in defects in bone collar formation and late hypertrophic chondrocyte maturation leading to decreased mineralization and less bone. 2009 Wiley-Liss, Inc.

  2. Downregulated bone morphogenetic protein signaling in nitrofen-induced congenital diaphragmatic hernia.

    PubMed

    Makanga, Martine; Dewachter, Céline; Maruyama, Hidekazu; Vuckovic, Aline; Rondelet, Benoit; Naeije, Robert; Dewachter, Laurence

    2013-08-01

    Bone morphogenetic proteins (BMP) have been shown to play crucial roles in not only lung and heart development, but also in the pathogenesis of pulmonary vascular remodeling in pulmonary hypertension (PH). We therefore hypothesized that BMP signaling could be altered in nitrofen-induced congenital diaphragmatic hernia (CDH) and associated PH. Pregnant rats were exposed to either 100 mg nitrofen or vehicle on embryonic day (E) 9.5. On E17 and E21, fetuses were delivered by cesarean section, killed and checked for left-sided CDH. The tissue was then harvested for pathobiological evaluation. In nitrofen-induced CDH, pulmonary expressions of BMP4, BMP receptor (BMPR) type 2 and Id1 decreased on E17 and E21. On E17, pulmonary gremlin-1 expression increased, while BMP7 decreased. In the lungs, Id1 expression was correlated to BMP4 and BMPR2 and inversely correlated to gremlin-1 expression. Myocardial expressions of BMPR2, BMPR1A, BMP7 and SERCA-2A decreased, while gremlin-1 and noggin expressions increased on E17. On E21, myocardial expressions of Id1 and SERCA-2A decreased, while gremlin-1 expression increased. Moreover, BMPR2 and BMPR1A expressions were correlated to SERCA-2A expression and inversely correlated to pro-apoptotic Bax/Bcl2 ratio within the myocardium. Downregulation of BMP signaling seems to contribute to pulmonary and myocardial anomalies observed in nitrofen-induced CDH.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mogi, Makio, E-mail: makio@dpc.aichi-gakuin.ac.jp; Kondo, Ayami

    Osteoprotegerin (OPG)/osteoclastogenesis inhibitory factor regulates bone mass by inhibiting osteoclastic bone resorption. mTOR, which is the mammalian target of rapamycin, is a kinase and central regulator of cell growth, proliferation, and survival. By using Rapamycin, we studied whether mTOR pathway is associated with OPG protein production in the mouse bone marrow-derived stromal cell line ST2. Rapamycin markedly increased the level of soluble OPG in ST2 cells. This antibiotic treatment resulted in the suppression of phosphorylation of mTOR. Rapamycin had no effects on the proliferation, differentiation, or apoptosis of the cells. Treatment with bone morphogenetic protein-4, which can induce OPG proteinmore » in ST2 cells, also resulted in a decrease in the density of the phospho-mTOR-band, suggesting that the suppression of the phospho-mTOR pathway is necessary for OPG production in ST2 cells. Thus, suitable suppression of mTOR phosphorylation is a necessary requirement for OPG production in bone marrow stromal cells.« less

  4. Heterotopic bone formation around sintered porous-surfaced Ti-6Al-4V implants coated with native bone morphogenetic proteins.

    PubMed

    Simon, Ziv; Deporter, Douglas A; Pilliar, Robert M; Clokie, Cameron M

    2006-09-01

    Coating endosseous dental implants with growth factors such as bone morphogenetic proteins (BMPs) may be one way to accelerate and/or enhance the quality of osseointegration. The purpose of this study was to investigate in the murine muscle pouch model whether sintered porous-surfaced titanium alloy implants coated with BMPs would lead to heterotopic bone formation around and within the implant surface geometry. Porous-surfaced dental implants were coated with partially purified native human BMPs, with or without a carrier of Poloxamer 407 (BASF Corp., Parsippany, NJ), placed in gelatin capsules and implanted into the hindquarter muscles of mice. Mice were euthanized after 28 days. Sections of retrieved specimens were subsequently prepared for morphometric analysis of bone formation using backscatter electron microscopic images. Human BMPs, either with or without the carrier of Poloxamer 407, led to bone formation within and outside of the sintered porous implant surface. When the sintered implant surface region was subdivided into inner and outer halves, similar levels of bone ingrowth and contact were seen in the 2 halves. Evidence of bone formation to the depth of the solid implant core (i.e., the deepest level possible) also was seen. Sintered porous-surfaced dental implants can be used as substrate for partially purified BMPs in the murine muscle pouch model. With the addition of these osteoinductive factors, the porous implant surface supported bone formation within the surface porosity provided, in some instances, all the way to the solid implant core. The addition of growth factors to a sintered porous surface may be an efficient method for altering locally the healing sequence and quality of bone associated with osseointegration of bone-interfacing implants.

  5. Insulin-like growth factor-1 (IGF-1) enhances the osteogenic activity of bone morphogenetic protein-6 (BMP-6) in vitro and in vivo, and together have a stronger osteogenic effect than when IGF-1 is combined with BMP-2.

    PubMed

    Rico-Llanos, Gustavo A; Becerra, Jose; Visser, Rick

    2017-07-01

    Bone morphogenetic protein-2 (BMP-2) is widely used in orthopedic surgery and bone tissue engineering because of its strong osteogenic activity. However, BMP-2 treatments have several drawbacks and many groups are actively exploring alternatives. Since BMP-6 has been demonstrated to be more osteoinductive, its use, either alone or together with other growth factors, might be an interesting option. In this work, we have compared the effect of BMP-2, BMP-6, or insulin-like growth factor-1 (IGF-1), either alone or in combination. Murine preosteoblasts were treated with 15 nM IGF-1 and/or 6 nM BMP-2 or -6 and the expression of osteogenic marker genes, proliferation, and alkaline phosphatase (ALP) activity in vitro were analyzed. The results showed that IGF-1 greatly enhanced the BMP-induced osteogenic differentiation of these cells in general and that the ALP activity in the cultures was higher when the combination was made with BMP-6 than with BMP-2. Furthermore, we tested the osteogenic potential of these treatments in vivo by loading 25 pmoles of IGF-1 and/or 10 pmoles of BMP-2 or -6 onto absorbable collagen sponges and implanting them into an ectopic bone formation model in rats. This study revealed that only BMP-6 was able to induce bone formation at the used dose and that the addition of IGF-1 contributed to an increase of the mineralization in the implants. Hence, the combination of BMP-6 with IGF-1 might be a better alternative than BMP-2 for orthopedic surgery or bone tissue engineering approaches. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1867-1875, 2017. © 2017 Wiley Periodicals, Inc.

  6. The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1, Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket

    PubMed Central

    Liu, Chang; Wu, Zhe; Sun, Hong-chen

    2009-01-01

    Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 (TGF-β1), bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups (n=24). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-β1 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket. PMID:20687301

  7. Alteration of Bone Mineral Density Differs Between Genders in Obese Subjects After Laparoscopic Sleeve Gastrectomy: Bone Morphogenetic Protein 4 May Count.

    PubMed

    Wang, Xingchun; Li, Liang; Zhu, Cuiling; Gao, Jingyang; Qu, Shen

    2018-05-12

    Laparoscopic sleeve gastrectomy (LSG) has proven to be successful in weight reduction but with potential loss of bone mass. Previous studies indicated that bone morphogenetic protein 4 (BMP4) plays an important role in both bone formation and glucose-lipid metabolism. This study aimed to investigate the changes in bone mineral density (BMD), bone metabolic parameters, and serum BMP4 levels in obese Chinese subjects after LSG. Seventy-one obese patients (34 males, age 31.70 ± 9.61 years and 37 females, age 32.80 ± 11.45 years) were enrolled. BMD (at the right hip, femoral neck, and lumbar spine 1-4 (L1-L4)) was measured by dual-energy X-ray absorptiometry, bone metabolic markers, and routine anthropometric/laboratory biochemical parameters at baseline, 3, 6, and 12 months after LSG (abbreviated as 3, 6, and 12 M post-LSG, respectively) were recorded. Serum BMP4 levels were measured by enzyme-linked immunosorbent assay. LSG led to dramatic weight loss with improved glucose-lipid metabolism in all patients. In females, BMD was significantly decreased at the right hip at all time points studied and at the femoral neck at 6 and 12 M post-LSG (P < 0.05 or P < 0.01). In males, BMD was not significantly changed (all P > 0.05). Intriguingly, serum BMP4 levels were reduced slightly at 3 M post-LSG (P = 0.463) and were significantly at 6 M post-LSG (from 75.51 ± 16.54 to 65.40 ± 10.51 pg/mL, P = 0.048) in females, but unchanged in males (all P > 0.05). Vitamin D and 25-hydroxy vitamin D were increased in males at 12 M post-LSG (all P < 0.05). Osteocalcin was increased in males at all time points studied and in females at 3 and 6 M post-LSG (all P < 0.05). Type I collagen was increased in males at 3 and 6 M post-LSG and in females at all the time points studied (all P < 0.05). The effect of LSG on BMD differs between genders, decreasing significantly in females while remaining unchanged in males. Moreover, decreased BMP4 levels may partly account for the diminished BMD in obese Chinese female patients after LSG.

  8. Effectiveness and harms of recombinant human bone morphogenetic protein-2 in spine fusion: a systematic review and meta-analysis.

    PubMed

    Fu, Rongwei; Selph, Shelley; McDonagh, Marian; Peterson, Kimberly; Tiwari, Arpita; Chou, Roger; Helfand, Mark

    2013-06-18

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) is used as a bone graft substitute in spinal fusion, which unites (fuses) bones in the spine. The accuracy and completeness of journal publications of industry-sponsored trials on the effectiveness and harms of rhBMP-2 has been called into question. To independently assess the effectiveness and harms of rhBMP-2 in spinal fusion and reporting bias in industry-sponsored journal publications. Individual-patient data (IPD) from 17 industry-sponsored studies; related internal documents; and searches of MEDLINE (1996 to August 2012), other databases, and reference lists. Randomized, controlled trials (RCTs) and cohort studies of rhBMP-2 versus any control and uncontrolled studies of harms. Effectiveness outcomes in IPD were recalculated using consistent definitions. Study characteristics and results were abstracted by 1 investigator and confirmed by another. Two investigators independently assessed quality using predefined criteria. Thirteen RCTs and 31 cohort studies were included. For lumbar spine fusion, rhBMP-2 and iliac crest bone graft were similar in overall success, fusion, and other effectiveness measures and in risk for any adverse event, although rates were high across interventions (77% to 93% at 24 months from surgery). For anterior lumbar interbody fusion, rhBMP-2 was associated with nonsignificantly increased risk for retrograde ejaculation and urogenital problems. For anterior cervical spine fusion, rhBMP-2 was associated with increased risk for wound complications and dysphagia. At 24 months, the cancer risk was increased with rhBMP-2 (risk ratio, 3.45 [95% CI, 1.98 to 6.00]), but event rates were low and cancer was heterogeneous. Early journal publications misrepresented the effectiveness and harms through selective reporting, duplicate publication, and underreporting. Outcome assessment was not blinded, and ascertainment of harms in trials was poor. No trials were truly independent of industry sponsorship. In spinal fusion, rhBMP-2 has no proven clinical advantage over bone graft and may be associated with important harms, making it difficult to identify clear indications for rhBMP-2. Earlier disclosure of all relevant data would have better informed clinicians and the public than the initial published trial reports did. Yale University and Medtronic.

  9. Chitosan-Graphene Oxide 3D scaffolds as Promising Tools for Bone Regeneration in Critical-Size Mouse Calvarial Defects.

    PubMed

    Hermenean, Anca; Codreanu, Ada; Herman, Hildegard; Balta, Cornel; Rosu, Marcel; Mihali, Ciprian Valentin; Ivan, Alexandra; Dinescu, Sorina; Ionita, Mariana; Costache, Marieta

    2017-11-30

    Limited self-regenerating capacity of human skeleton makes the reconstruction of critical size bone defect a significant challenge for clinical practice. Aimed for regenerating bone tissues, this study was designed to investigate osteogenic differentiation, along with bone repair capacity of 3D chitosan (CHT) scaffolds enriched with graphene oxide (GO) in critical-sized mouse calvarial defect. Histopathological/histomorphometry and scanning electron microscopy(SEM) analysis of the implants revealed larger amount of new bone in the CHT/GO-filled defects compared with CHT alone (p < 0.001). When combined with GO, CHT scaffolds synergistically promoted the increase of alkaline phosphatase activity both in vitro and in vivo experiments. This enhanced osteogenesis was corroborated with increased expression of bone morphogenetic protein (BMP) and Runx-2 up to week 4 post-implantation, which showed that GO facilitates the differentiation of osteoprogenitor cells. Meanwhile, osteogenesis was promoted by GO at the late stage as well, as indicated by the up-regulation of osteopontin and osteocalcin at week 8 and overexpressed at week 18, for both markers. Our data suggest that CHT/GO biomaterial could represent a promising tool for the reconstruction of large bone defects, without using exogenous living cells or growth factors.

  10. Physiological exercise loading suppresses post-traumatic osteoarthritis progression via an increase in bone morphogenetic proteins expression in an experimental rat knee model.

    PubMed

    Iijima, H; Ito, A; Nagai, M; Tajino, J; Yamaguchi, S; Kiyan, W; Nakahata, A; Zhang, J; Wang, T; Aoyama, T; Nishitani, K; Kuroki, H

    2017-06-01

    To evaluate the dose-response relationship of exercise loading in the cartilage-subchondral bone (SB) unit in surgically-induced post-traumatic osteoarthritis (PTOA) of the knee. Destabilized medial meniscus (DMM) surgery was performed on the right knee of 12-week-old male Wistar rats, and sham surgery was performed on the contralateral knee. Four weeks after the surgery, the animals were subjected to moderate (12 m/min) or intense (21 m/min) treadmill exercises for 30 min/day, 5 days/week for 4 weeks. PTOA development in articular cartilage and SB was examined using histological and immunohistochemical analyses, micro-computed tomography (micro-CT) analysis, and biomechanical testing at 8 weeks after surgery. Gremlin-1 was injected to determine the role of bone morphogenetic protein (BMP) signaling on PTOA development following moderate exercise. Moderate exercise increased BMP-2, BMP-4, BMP-6, BMP receptor 2, pSmad-5, and inhibitor of DNA binding protein-1 expression in the superficial zone chondrocytes and suppressed cartilage degeneration, osteophyte growth, SB damage, and osteoclast-mediated SB resorption. However, intense exercise had little effect on BMP expression and even caused progression of these osteoarthritis (OA) changes. Gremlin-1 injection following moderate exercise caused progression of the PTOA development down to the level of the non-exercise DMM-operated knee. Exercise regulated cartilage-SB PTOA development in DMM-operated knees in a dose-dependent manner. Our findings shed light on the important role of BMP expression in superficial zone chondrocytes in attenuation of PTOA development following physiological exercise loading. Further studies to support a mechanism by which BMPs would be beneficial in preventing PTOA progression are warranted. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  11. Runx2 mediates epigenetic silencing of the bone morphogenetic protein-3B (BMP-3B/GDF10) in lung cancer cells

    PubMed Central

    2012-01-01

    Background The Runt-related transcription factor Runx2 is essential for bone development but is also implicated in progression of several cancers of breast, prostate and bone, where it activates cancer-related genes and promotes invasive properties. The transforming growth factor β (TGF-β) family member bone morphogenetic protein-3B (BMP-3B/GDF10) is regarded as a tumor growth inhibitor and a gene silenced in lung cancers; however the regulatory mechanisms leading to its silencing have not been identified. Results Here we show that Runx2 is highly expressed in lung cancer cells and downregulates BMP-3B. This inverse relationship between Runx2 and BMP-3B expression is further supported by increased expression of BMP-3B in mesenchymal cells from Runx2 deficient mice. The ectopic expression of Runx2, but not DNA binding mutant Runx2, in normal lung fibroblast cells and lung cancer cells resulted in suppression of BMP-3B levels. The chromatin immunoprecipitation studies identified that the mechanism of Runx2-mediated suppression of BMP-3B is due to the recruitment of Runx2 and histone H3K9-specific methyltransferase Suv39h1 to BMP-3B proximal promoter and a concomitant increase in histone methylation (H3K9) status. The knockdown of Runx2 in H1299 cells resulted in decreased histone H3K9 methylation on BMP-3B promoter and increased BMP-3B expression levels. Furthermore, co-immunoprecipitation studies showed a direct interaction of Runx2 and Suv39h1 proteins. Phenotypically, Runx2 overexpression in H1299 cells increased wound healing response to TGFβ treatment. Conclusions Our studies identified BMP-3B as a new Runx2 target gene and revealed a novel function of Runx2 in silencing of BMP-3B in lung cancers. Our results suggest that Runx2 is a potential therapeutic target to block tumor suppressor gene silencing in lung cancer cells. PMID:22537242

  12. Low-intensity pulsed ultrasound enhances bone morphogenetic protein expression of human mandibular fracture haematoma-derived cells.

    PubMed

    Huang, W; Hasegawa, T; Imai, Y; Takeda, D; Akashi, M; Komori, T

    2015-07-01

    We previously demonstrated that human mandibular fracture haematoma-derived cells (MHCs) play an important role in mandibular fracture healing and that low-intensity pulsed ultrasound (LIPUS) accelerates this effect by stimulating various osteogenic cytokines. In the present study, we investigated how LIPUS affects the expression of bone morphogenetic proteins (BMPs), which are also known to have the ability to induce bone formation. MHCs were isolated from human mandibular fracture haematomas and the cells were divided into two groups: a LIPUS (+) group and a LIPUS (-) group, both of which were cultured in osteogenic medium. LIPUS was applied to the LIPUS (+) group 20 min a day for 4, 8, 14, and 20 days (1.5 MHz, 30 mW/cm(2)). Real-time PCR and immunofluorescence studies were carried out to determine the expression of BMP-2, 4, and 7. Compared to the LIPUS (-) group, gene expression levels were significantly increased in the LIPUS (+) group for BMP-2 on day 20 (67.38 ± 26.59 vs. 11.52 ± 3.42, P < 0.001), for BMP-4 on days 14 (45.12 ± 11.06 vs. 9.20 ± 2.88, P = 0.045) and 20 (40.96 ± 24.81 vs. 3.22 ± 1.53, P = 0.035), and for BMP-7 on day 8 (48.11 ± 35.36 vs. 7.03 ± 3.96, P = 0.034). These findings suggest that BMP-2, 4, and 7 may be mediated by LIPUS therapy during the bone repair process. Copyright © 2015 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Two Variants of Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) with Additional Protein Domains: Synthesis in an Escherichia coli Heterologous Expression System.

    PubMed

    Karyagina, A S; Boksha, I S; Grunina, T M; Demidenko, A V; Poponova, M S; Sergienko, O V; Lyashchuk, A M; Galushkina, Z M; Soboleva, L A; Osidak, E O; Bartov, M S; Gromov, A V; Lunin, V G

    2017-05-01

    Two variants of recombinant human bone morphogenetic protein-2 (rhBMP-2) with additional N-terminal protein domains were obtained by expression in E. coli. The N-terminal domains were s-tag (15-a.a. oligopeptide from bovine pancreatic ribonuclease A) and lz (leucine zipper dimerization domain from yeast transcription factor GCN4). The s-tag-BMP-2 and lz-BMP-2 were purified by a procedure that excluded a long refolding stage. The resulting dimeric proteins displayed higher solubility compared to rhBMP-2 without additional protein domains. Biological activity of both proteins was demonstrated in vitro by induction of alkaline phosphatase in C2C12 cells, and the activity of s-tag-BMP-2 in vivo was shown in various experimental animal models.

  14. Repulsive Guidance Molecules (RGMs) and Neogenin in Bone Morphogenetic Protein (BMP) signaling

    PubMed Central

    Tian, Chenxi; Liu, Jun

    2015-01-01

    Summary Bone morphogenetic proteins (BMPs) belong to the transforming growth factor-beta (TGFβ) superfamily. BMPs mediate a highly conserved signal transduction cascade through the type I and type II serine/threonine kinase receptors and intracellular Smad proteins. The BMP pathway regulates multiple developmental and homeostatic processes. Mutations in this pathway can cause various diseases in humans, such as skeletal disorders, cardiovascular diseases and various cancers. Multiple levels of regulation, including extracellular regulation, help to ensure proper spatiotemporal control of BMP signaling in the right cellular context. The family of repulsive guidance molecules (RGMs) and the type I trans-membrane protein neogenin, a paralog of DCC (Deleted in Colorectal Cancer), have been implicated in modulating the BMP pathway. In this review, we discuss the properties and functions of RGM proteins and neogenin, focusing on their roles in the modulation of BMP signal transduction. PMID:23740870

  15. Inhibition of bone morphogenetic protein signaling attenuates anemia associated with inflammation

    PubMed Central

    Steinbicker, Andrea U.; Sachidanandan, Chetana; Vonner, Ashley J.; Yusuf, Rushdia Z.; Deng, Donna Y.; Lai, Carol S.; Rauwerdink, Kristen M.; Winn, Julia C.; Saez, Borja; Cook, Colleen M.; Szekely, Brian A.; Roy, Cindy N.; Seehra, Jasbir S.; Cuny, Gregory D.; Scadden, David T.; Peterson, Randall T.; Bloch, Kenneth D.

    2011-01-01

    Anemia of inflammation develops in settings of chronic inflammatory, infectious, or neoplastic disease. In this highly prevalent form of anemia, inflammatory cytokines, including IL-6, stimulate hepatic expression of hepcidin, which negatively regulates iron bioavailability by inactivating ferroportin. Hepcidin is transcriptionally regulated by IL-6 and bone morphogenetic protein (BMP) signaling. We hypothesized that inhibiting BMP signaling can reduce hepcidin expression and ameliorate hypoferremia and anemia associated with inflammation. In human hepatoma cells, IL-6–induced hepcidin expression, an effect that was inhibited by treatment with a BMP type I receptor inhibitor, LDN-193189, or BMP ligand antagonists noggin and ALK3-Fc. In zebrafish, the induction of hepcidin expression by transgenic expression of IL-6 was also reduced by LDN-193189. In mice, treatment with IL-6 or turpentine increased hepcidin expression and reduced serum iron, effects that were inhibited by LDN-193189 or ALK3-Fc. Chronic turpentine treatment led to microcytic anemia, which was prevented by concurrent administration of LDN-193189 or attenuated when LDN-193189 was administered after anemia was established. Our studies support the concept that BMP and IL-6 act together to regulate iron homeostasis and suggest that inhibition of BMP signaling may be an effective strategy for the treatment of anemia of inflammation. PMID:21393479

  16. Chordin-Like 1 Suppresses Bone Morphogenetic Protein 4-Induced Breast Cancer Cell Migration and Invasion

    PubMed Central

    Cyr-Depauw, Chanèle; Northey, Jason J.; Tabariès, Sébastien; Annis, Matthew G.; Dong, Zhifeng; Cory, Sean; Hallett, Michael; Rennhack, Jonathan P.; Andrechek, Eran R.

    2016-01-01

    ShcA is an important mediator of ErbB2- and transforming growth factor β (TGF-β)-induced breast cancer cell migration, invasion, and metastasis. We show that in the context of reduced ShcA levels, the bone morphogenetic protein (BMP) antagonist chordin-like 1 (Chrdl1) is upregulated in numerous breast cancer cells following TGF-β stimulation. BMPs have emerged as important modulators of breast cancer aggressiveness, and we have investigated the ability of Chrdl1 to block BMP-induced increases in breast cancer cell migration and invasion. Breast cancer-derived conditioned medium containing elevated concentrations of endogenous Chrdl1, as well as medium containing recombinant Chrdl1, suppresses BMP4-induced signaling in multiple breast cancer cell lines. Live-cell migration assays reveal that BMP4 induces breast cancer migration, which is effectively blocked by Chrdl1. We demonstrate that BMP4 also stimulated breast cancer cell invasion and matrix degradation, in part, through enhanced metalloproteinase 2 (MMP2) and MMP9 activity that is antagonized by Chrdl1. Finally, high Chrdl1 expression was associated with better clinical outcomes in patients with breast cancer. Together, our data reveal that Chrdl1 acts as a negative regulator of malignant breast cancer phenotypes through inhibition of BMP signaling. PMID:26976638

  17. Attenuated BMP1 Function Compromises Osteogenesis, Leading to Bone Fragility in Humans and Zebrafish

    PubMed Central

    Asharani, P.V.; Keupp, Katharina; Semler, Oliver; Wang, Wenshen; Li, Yun; Thiele, Holger; Yigit, Gökhan; Pohl, Esther; Becker, Jutta; Frommolt, Peter; Sonntag, Carmen; Altmüller, Janine; Zimmermann, Katharina; Greenspan, Daniel S.; Akarsu, Nurten A.; Netzer, Christian; Schönau, Eckhard; Wirth, Radu; Hammerschmidt, Matthias; Nürnberg, Peter; Wollnik, Bernd; Carney, Thomas J.

    2012-01-01

    Bone morphogenetic protein 1 (BMP1) is an astacin metalloprotease with important cellular functions and diverse substrates, including extracellular-matrix proteins and antagonists of some TGFβ superfamily members. Combining whole-exome sequencing and filtering for homozygous stretches of identified variants, we found a homozygous causative BMP1 mutation, c.34G>C, in a consanguineous family affected by increased bone mineral density and multiple recurrent fractures. The mutation is located within the BMP1 signal peptide and leads to impaired secretion and an alteration in posttranslational modification. We also characterize a zebrafish bone mutant harboring lesions in bmp1a, demonstrating conservation of BMP1 function in osteogenesis across species. Genetic, biochemical, and histological analyses of this mutant and a comparison to a second, similar locus reveal that Bmp1a is critically required for mature-collagen generation, downstream of osteoblast maturation, in bone. We thus define the molecular and cellular bases of BMP1-dependent osteogenesis and show the importance of this protein for bone formation and stability. PMID:22482805

  18. Bone morphogenetic protein Smads signaling in mesenchymal stem cells affected by osteoinductive calcium phosphate ceramics.

    PubMed

    Tang, Zhurong; Wang, Zhe; Qing, Fangzhu; Ni, Yilu; Fan, Yujiang; Tan, Yanfei; Zhang, Xingdong

    2015-03-01

    Porous calcium phosphate ceramics (CaP ceramics) could induce ectopic bone formation which was regulated by various signal molecules. In this work, bone marrow mesenchymal stem cells (MSCs) were cultured on the surface of osteoinductive hydroxyapatite (HA) and biphasic calcium phosphate (BCP) ceramics in comparison with control (culture plate) for up to 14 days to detect the signal molecules which might be affected by the CaP ceramics. Without adding osteogenic factors, MSCs cultured on HA and BCP both expressed higher Runx2, Osterix, collagen type I, osteopontin, bone sialoprotein, and osteocalcin at various stages compared with control, thus confirmed the osteoblastic differentiation of MSCs. Later study demonstrated the messenger RNA level of bone morphogenetic protein 2 (BMP2) and BMP4 were also significantly enhanced by HA and BCP. Furthermore, Smad1, 4, 5, and Dlx5, the main molecules in the BMP/Smads signaling pathway, were upregulated by HA and BCP. Moreover, the higher expression of Smads and BMP2, 4 in BCP over HA, corresponded to the better performance of BCP in stimulating in vitro osteoblastic differentiation of MSCs. This was in accordance with the better osteoinductivity of BCP over HA in vivo. Altogether, these results implied that the CaP ceramics may initiate the osteoblastic differentiation of MSCs by influencing the expression of molecules in BMP/Smads pathway. © 2014 Wiley Periodicals, Inc.

  19. A poly (lactide-co-glycolide) film loaded with abundant bone morphogenetic protein-2: A substrate promoting osteoblast attachment, proliferation and differentiation in bone tissue engineering.

    PubMed

    Qu, Xiangyang; Cao, Yujiang; Chen, Cong; Die, Xiaohong; Kang, Quan

    2014-12-10

    We explored a novel biodegradable poly (lactide-co-glycolide) (PLGA) film loaded with over 80 wt% bone morphogenetic protein (BMP-2), which was regarded as a substrate promoting osteoblast attachment, proliferation and differentiation for application of bone tissue engineering. Using phospholipid as a surfactant, BMP-2 was modified as a complex (PBC) for dispersing in PLGA/dichloromethane solution. The PLGA film loaded with BMP-2 and phospholipid complex (PBC-PF) showed rough and draped morphology with high entrapment efficiency exceeding 80% and good hydrophilicity respectively. The in-vitro release study of BMP-2 showed that about 50% BMP-2 was slowly and continuously released from PBC-PF within 5 weeks and had a short initial burst release only in the last 1.5 days, which was better than serious burst release of PLGA film loaded with pure BMP-2 without phospholipid (BMP-PF) controlling. By comparison with other PLGA films and tissue culture plates, it was confirmed that PBC-PF significantly promoted the attachment, proliferation and differentiation of osteoblasts with higher entrapment efficiency and better sustained release. These advantages illustrated that PBC-PF could be a potential substrate providing long-term requisite growth factors for osteoblasts, which might be applied in bone tissue engineering. This article is protected by copyright. All rights reserved. Copyright © 2014 Wiley Periodicals, Inc., A Wiley Company.

  20. A poly(lactide-co-glycolide) film loaded with abundant bone morphogenetic protein-2: A substrate-promoting osteoblast attachment, proliferation, and differentiation in bone tissue engineering.

    PubMed

    Qu, Xiangyang; Cao, Yujiang; Chen, Cong; Die, Xiaohong; Kang, Quan

    2015-08-01

    We explored a novel biodegradable poly(lactide-co-glycolide) (PLGA) film loaded with over 80 wt % bone morphogenetic protein (BMP)-2, which was regarded as a substrate-promoting osteoblast attachment, proliferation, and differentiation for application of bone tissue engineering. Using phospholipid as a surfactant, BMP-2 was modified as a complex (PBC) for dispersing in PLGA/dichloromethane solution. The PLGA film loaded with BMP-2 and phospholipid complex (PBC-PF) showed rough and draped morphology with high entrapment efficiency exceeding 80% and good hydrophilicity, respectively. The in vitro release study of BMP-2 showed that about 50% BMP-2 was slowly and continuously released from PBC-PF within 5 weeks and had a short initial burst release only in the last 1.5 days, which was better than serious burst release of PLGA film loaded with pure BMP-2 without phospholipid (BMP-PF) as control. By comparison with other PLGA films and tissue culture plates, it was confirmed that PBC-PF significantly promoted the attachment, proliferation, and differentiation of osteoblasts with higher entrapment efficiency and better sustained release. These advantages illustrated that PBC-PF could be a potential substrate providing long-term requisite growth factors for osteoblasts, which might be applied in bone tissue engineering. © 2015 Wiley Periodicals, Inc.

  1. Off-label use of rhBMP-2 as bone regeneration strategies in mandibular ameloblastoma unicystic.

    PubMed

    Silva, Henrique Celestino Lima E; Cheim, Adonai Peixoto; Moreno, Roberto; Miranda, Sérgio Luis de

    2017-01-01

    Jawbone reconstruction after tumor resection is one of the most challenging clinical tasks for maxillofacial surgeons. Osteogenic, osteoinductive, osteoconductive and non-antigenic properties of autogenous bone place this bone as the gold standard for solving problems of bone availability. However, the need for a second surgical site to harvest the bone graft increases significantly both the cost and the morbidity associated with the reconstructive procedures. Bone grafting gained an important tool with the discovery of bone morphogenetic proteins in 1960. Benefit of obtaining functional and real bone matrix without need of second surgical site seems to be the great advantage of use bone morphogenetic proteins. This study analyzed the use of rhBMP-2 in unicystic ameloblastoma of the mandible, detailing its structure, mechanisms of cell signaling and biological efficacy, in addition to present possible advantages and disadvantages of clinical use of rhBMP-2 as bone regeneration strategy. RESUMO A reconstrução óssea dos maxilares após ressecções tumorais é uma das tarefas mais difíceis para o cirurgião maxilofacial. As propriedades osteogênicas, osteoindutoras, osteocondutoras e não antigênicas do osso autógeno o colocam como o padrão-ouro para a solução de problemas de disponibilidade óssea. Entretanto a coleta do enxerto ósseo necessita de um segundo sítio cirúrgico, aumentando significativamente o custo e a morbidade associados ao procedimento reconstrutivo. A enxertia óssea ganhou uma excelente ferramenta com a descoberta das proteínas ósseas morfogenéticas na década de 1960. O benefício da obtenção de matriz óssea verdadeira e funcional, sem a necessidade de um segundo sítio cirúrgico, parece ser a grande vantagem do uso das proteínas ósseas morfogenéticas. Neste contexto, o objetivo deste estudo foi analisar a utilização da rhBMP-2 na regeneração óssea de ameloblastoma mandibular unicístico, detalhando sua estrutura, seus mecanismos de sinalização celular e sua eficácia biológica, além de apresentar potenciais vantagens e desvantagens da utilização clínica das rhBMP-2, enquanto estratégia regenerativa.

  2. Randomized, controlled clinical two-centre study using xenogeneic block grafts loaded with recombinant human bone morphogenetic protein-2 or autogenous bone blocks for lateral ridge augmentation.

    PubMed

    Thoma, Daniel S; Payer, Michael; Jakse, Norbert; Bienz, Stefan P; Hüsler, Jürg; Schmidlin, Patrick R; Jung, Ui-Won; Hämmerle, Christoph H F; Jung, Ronald E

    2018-02-01

    To test whether or not the use of a xenogeneic block loaded with recombinant human bone morphogenetic protein-2 (rhBMP-2) results in different bone quantity and quality compared to an autogenous bone block. Twenty-four patients with insufficient bone volume for implant placement were randomly assigned to two treatment modalities: a xenogeneic bone block loaded with rhBMP-2 (test) and an autogenous bone block (control). The horizontal ridge width was evaluated prior to augmentation, after augmentation and at 4 months. Patient-reported outcome measures (PROMs) were assessed at suture removal and at 4 months. Biopsies were obtained at 4 months and histologically evaluated. Intergroup comparisons were tested by a two-sided Wilcoxon-Mann-Whitney test, intra-group comparisons were performed with Wilcoxon-signed rank test, and all categorical variables were tested with Chi-squared tests. One autogenous bone block failed. This patient was replaced, and in all subsequently treated 24 patients, implant placement was possible 4 months later. The median ridge width increased from 4.0 mm (Q1 = 2.0; Q3 = 4.0) (test) and 2.0 mm (Q1 = 2.0; Q3 = 3.0) (control) to 7.0 mm (Q1 = 6.0; Q3 = 8.0) (test) and 7.0 mm (Q1 = 6.0; Q3 = 8.0) (control) at 4 months (intergroup p > .05). A higher morbidity was reported at the augmented site in the control group during surgery. Sensitivity was more favourable in the test than that in the control group at 4 months. The biopsies revealed more mineralized tissue in the control group (p < .0043). Both treatment modalities were successful in regenerating bone to place dental implants. PROMs did not reveal any significant differences between the groups except for pain during surgery at the recipient site (in favour of the test group). Histologically, a higher amount of mineralized tissue was observed for the control group at 4 months. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Ex vivo bone morphogenetic protein 2 gene delivery using periodontal ligament stem cells for enhanced re-osseointegration in the regenerative treatment of peri-implantitis.

    PubMed

    Park, Shin-Young; Kim, Kyoung-Hwa; Gwak, Eun-Hye; Rhee, Sang-Hoon; Lee, Jeong-Cheol; Shin, Seung-Yun; Koo, Ki-Tae; Lee, Yong-Moo; Seol, Yang-Jo

    2015-01-01

    Peri-implantitis is a chronic inflammatory process with advanced bone loss and impaired healing potential. For peri-implantitis treatment, tissue engineering can be applied to enhance bone regeneration of peri-implant defects. This study aimed to evaluate ex vivo bone morphogenetic protein 2 (BMP2) gene delivery using canine periodontal ligament stem cells (PDLSCs) for regeneration of peri-implantitis defects. Canine PDLSCs were transduced with adenoviral vectors containing BMP2 (BMP2/PDLSCs). After peri-implantitis was induced by ligature placement in six beagle dogs, regenerative procedures were performed; hydroxyapatite (HA) particles and collagen gel with autologous canine PDLSCs (PDLSC group) or BMP2/PDLSCs (BMP/PDLSC group) or without cells (control group) were grafted into the defects and covered by an absorbable membrane. Three months later, the animals were sacrificed. In vitro, BMP2/PDLSCs showed similar levels of stem cell properties to PDLSCs, such as colony-forming efficiency and expression of MSC markers STRO-1 and CD 146. BMP2/PDLSCs produced BMP-2 until day 21 at a concentration of 4-8 ng/mL. In vivo, the BMP2/PDLSC group showed significantly more new bone formation and re-osseointegration in peri-implantitis defects compared to the other groups. In conclusion, ex vivo BMP2 gene delivery using PDLSCs enhanced new bone formation and re-osseointegration in peri-implantitis defects. © 2014 Wiley Periodicals, Inc.

  4. Radiographic Assessment of Bone Formation Using rhBMP2 at Maxillary Periapical Surgical Defects: A Case Series

    PubMed Central

    Kumar, M. Hari; Vishalakshi, K.; Sabitha, H.

    2016-01-01

    Periapical cysts are the most common inflammatory odontogenic cysts arising from untreated dental caries with pulp necrosis and periapical infection. The choice of treatment is often influenced by various factors like size, extension of the lesion, proximity to vital structures, systemic condition and compliance of the patient too. The treatment protocol for management of periapical cysts is still under discussion and options vary from conservative treatment by means of endodontic technique to surgical treatment like decompression or a marsupialisation or even to enucleation. Large bony defect secondary to periapical surgery compromising the tooth integrity often requires bone graft to enhance bone formation and thus restoring function at the earliest. The present case series included 10 patients who had established periapical pathology secondary to history of trauma on upper anterior teeth as well patients with history of carious teeth with an apparent failure in root canal therapy. All ten patients were treated with cyst enucleation and apiceotomy along with 1.4cc Recombinant Human Bone Morphogenetic Protein-2 soaked Absorbable Collagen Sponge implantation at surgical defect. Radiographs and clinical examinations were done upto 3 months to evaluate healing. Radiographic and clinical assessments revealed bone regeneration and restoration of the maxillary surgical defects in all 10 patients. No evidence of graft failure was noted. The Recombinant Human Bone Morphogenetic Protein-2 soaked Absorbable Collagen Sponge carrier is thus proved to be a viable option for the treatment of maxillary periapical surgical defects. PMID:27190972

  5. Radiographic Assessment of Bone Formation Using rhBMP2 at Maxillary Periapical Surgical Defects: A Case Series.

    PubMed

    Kumar, M Siva; Kumar, M Hari; Vishalakshi, K; Sabitha, H

    2016-04-01

    Periapical cysts are the most common inflammatory odontogenic cysts arising from untreated dental caries with pulp necrosis and periapical infection. The choice of treatment is often influenced by various factors like size, extension of the lesion, proximity to vital structures, systemic condition and compliance of the patient too. The treatment protocol for management of periapical cysts is still under discussion and options vary from conservative treatment by means of endodontic technique to surgical treatment like decompression or a marsupialisation or even to enucleation. Large bony defect secondary to periapical surgery compromising the tooth integrity often requires bone graft to enhance bone formation and thus restoring function at the earliest. The present case series included 10 patients who had established periapical pathology secondary to history of trauma on upper anterior teeth as well patients with history of carious teeth with an apparent failure in root canal therapy. All ten patients were treated with cyst enucleation and apiceotomy along with 1.4cc Recombinant Human Bone Morphogenetic Protein-2 soaked Absorbable Collagen Sponge implantation at surgical defect. Radiographs and clinical examinations were done upto 3 months to evaluate healing. Radiographic and clinical assessments revealed bone regeneration and restoration of the maxillary surgical defects in all 10 patients. No evidence of graft failure was noted. The Recombinant Human Bone Morphogenetic Protein-2 soaked Absorbable Collagen Sponge carrier is thus proved to be a viable option for the treatment of maxillary periapical surgical defects.

  6. Bone marrow-derived mesenchymal stem cells assembled with low-dose BMP-2 in a three-dimensional hybrid construct enhances posterolateral spinal fusion in syngeneic rats.

    PubMed

    Hu, Tao; Abbah, Sunny Akogwu; Toh, Soo Yein; Wang, Ming; Lam, Raymond Wing Moon; Naidu, Mathanapriya; Bhakta, Gajadhar; Cool, Simon M; Bhakoo, Kishore; Li, Jun; Goh, James Cho-Hong; Wong, Hee-Kit

    2015-12-01

    The combination of potent osteoinductive growth factor, functional osteoblastic cells, and osteoconductive materials to induce bone formation is a well-established concept in bone tissue engineering. However, supraphysiological dose of growth factor, such as recombinant human bone morphogenetic protein 2 (rhBMP-2), which is necessary in contemporary clinical application, have been reported to result in severe side effects. We hypothesize that the synergistic osteoinductive capacity of low-dose bone morphogenetic protein 2 (BMP-2) combined with undifferentiated bone marrow-derived stromal cells (BMSCs) is comparable to that of osteogenically differentiated BMSCs when used in a rodent model of posterolateral spinal fusion. A prospective study using a rodent model of posterolateral spinal fusion was carried out. Thirty-six syngeneic Fischer rats comprised the patient sample. Six groups of implants were evaluated as follows (n=6): (1) 10 µg BMP-2 with undifferentiated BMSCs; (2) 10 µg BMP-2 with osteogenic-differentiated BMSCs; (3) 2.5 µg BMP-2 with undifferentiated BMSCs; (4) 2.5 µg BMP-2 with osteogenic-differentiated BMSCs; (5) 0.5 µg BMP-2 with undifferentiated BMSCs; and (6) 0.5 µg BMP-2 with osteogenic-differentiated BMSCs. Optimal in vitro osteogenic differentiation of BMSCs was determined by quantitative real-time polymerase chain reaction (qRT-PCR) gene analysis whereas in vivo bone formation capacity was evaluated by manual palpation, micro-computed tomography, and histology. Rat BMSCs cultured in fibrin matrix that was loaded into the pores of medical-grade poly epsilon caprolactone tricalcium phosphate scaffolds differentiated toward osteogenic lineage by expressing osterix, runt-related transcription factor 2, and osteocalcium mRNA when supplemented with dexamethasone, ascorbic acid, and β-glycerophosphate. Whereas qRT-PCR revealed optimal increase in osteogenic genes expression after 7 days of in vitro culture, in vivo transplantation study showed that pre-differentiation of BMSCs before transplantation failed to promote posterolateral spinal fusion when co-delivered with low-dose BMP-2 (1/6 or 17% fusion rate). In contrast, combined delivery of undifferentiated BMSCs with low-dose BMP-2 (2.5 µg) demonstrated significantly higher fusion rate (4/6 or 67%) as well as significantly increased volume of new bone formation (p<.05). In summary, this study supports the combination of undifferentiated BMSCs and low-dose rhBMP-2 for bone tissue engineering construct. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Design and development of novel hyaluronate-modified nanoparticles for combo-delivery of curcumin and alendronate: Fabrication, characterization, and cellular and molecular evidence of enhanced bone regeneration.

    PubMed

    Dong, Jinlei; Thu, Hnin Ei; Abourehab, Mohammed A S; Hussain, Zahid

    2018-05-18

    Osteoporosis is a medical condition of fragile bones with an increased susceptibility to bone fracture. Despite having availability of a wide range of pharmacological agents, prevalence of this metabolic disorder is continuously escalating. Owing to excellent biomedical achievements of nanomedicines in the last few decades, we aimed combo delivery of bone anti-resorptive agent, alendronate (ALN), and bone density enhancing drug, curcumin (CUR), in the form of polymeric nanoparticles. To further optimize the therapeutic efficacy, the prepared ALN/CUR nanoparticles were decorated with hyaluronic acid which is a well-documented biomacromolecule having exceptional bone regenerating potential. The optimized nanoformulation was evaluated for bone regeneration efficacy by assessing the time-mannered modulation in the proliferation, differentiation, and mineralization of MC3T3-E1 cells, a pre-osteoblast model. Moreover, the time-mannered expressions of various bone-forming protein biomarkers including bone morphogenetic protein, runt related transcription factor 2, and osteocalcin were assessed in the cell lysates. Results revealed that HA-ALN/CUR NPs provoke remarkable increase in proliferation, differentiation, and mineralization in the ECM of MC3T3-E1 cells which ultimately leads to enhanced bone formation. This new strategy employing simultaneous delivery of anti-resorptive and bone forming agents would open new horizons for the scientists as an efficient alternative pharmacotherapy for the management of osteoporosis. Copyright © 2017. Published by Elsevier B.V.

  8. Autologous implantation of BMP2-expressing dermal fibroblasts to improve bone mineral density and architecture in rabbit long bones.

    PubMed

    Ishihara, Akikazu; Weisbrode, Steve E; Bertone, Alicia L

    2015-10-01

    Cell-mediated gene therapy may treat bone fragility disorders. Dermal fibroblasts (DFb) may be an alternative cell source to stem cells for orthopedic gene therapy because of their rapid cell yield and excellent plasticity with bone morphogenetic protein-2 (BMP2) gene transduction. Autologous DFb or BMP2-expressing autologous DFb were administered in twelve rabbits by two delivery routes; a transcortical intra-medullar infusion into tibiae and delayed intra-osseous injection into femoral drill defects. Both delivery methods of DFb-BMP2 resulted in a successful cell engraftment, increased bone volume, bone mineral density, improved trabecular bone microarchitecture, greater bone defect filling, external callus formation, and trabecular surface area, compared to non-transduced DFb or no cells. Cell engraftment within trabecular bone and bone marrow tissue was most efficiently achieved by intra-osseous injection of DFb-BMP2. Our results suggested that BMP2-expressing autologous DFb have enhanced efficiency of engraftment in target bones resulting in a measurable biologic response by the bone of improved bone mineral density and bone microarchitecture. These results support that autologous implantation of DFb-BMP2 warrants further study on animal models of bone fragility disorders, such as osteogenesis imperfecta and osteoporosis to potentially enhance bone quality, particularly along with other gene modification of these diseases. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  9. 3D bioprinting of methacrylated hyaluronic acid (MeHA) hydrogel with intrinsic osteogenicity.

    PubMed

    Poldervaart, Michelle T; Goversen, Birgit; de Ruijter, Mylene; Abbadessa, Anna; Melchels, Ferry P W; Öner, F Cumhur; Dhert, Wouter J A; Vermonden, Tina; Alblas, Jacqueline

    2017-01-01

    In bone regenerative medicine there is a need for suitable bone substitutes. Hydrogels have excellent biocompatible and biodegradable characteristics, but their visco-elastic properties limit their applicability, especially with respect to 3D bioprinting. In this study, we modified the naturally occurring extracellular matrix glycosaminoglycan hyaluronic acid (HA), in order to yield photo-crosslinkable hydrogels with increased mechanical stiffness and long-term stability, and with minimal decrease in cytocompatibility. Application of these tailor-made methacrylated hyaluronic acid (MeHA) gels for bone tissue engineering and 3D bioprinting was the subject of investigation. Visco-elastic properties of MeHA gels, measured by rheology and dynamic mechanical analysis, showed that irradiation of the hydrogels with UV light led to increased storage moduli and elastic moduli, indicating increasing gel rigidity. Subsequently, human bone marrow derived mesenchymal stromal cells (MSCs) were incorporated into MeHA hydrogels, and cell viability remained 64.4% after 21 days of culture. Osteogenic differentiation of MSCs occurred spontaneously in hydrogels with high concentrations of MeHA polymer, in absence of additional osteogenic stimuli. Addition of bone morphogenetic protein-2 (BMP-2) to the culture medium further increased osteogenic differentiation, as evidenced by increased matrix mineralisation. MeHA hydrogels demonstrated to be suitable for 3D bioprinting, and were printed into porous and anatomically shaped scaffolds. Taken together, photosensitive MeHA-based hydrogels fulfilled our criteria for cellular bioprinted bone constructs within a narrow window of concentration.

  10. 3D bioprinting of methacrylated hyaluronic acid (MeHA) hydrogel with intrinsic osteogenicity

    PubMed Central

    Poldervaart, Michelle T.; Goversen, Birgit; de Ruijter, Mylene; Abbadessa, Anna; Melchels, Ferry P. W.; Öner, F. Cumhur; Dhert, Wouter J. A.; Vermonden, Tina

    2017-01-01

    In bone regenerative medicine there is a need for suitable bone substitutes. Hydrogels have excellent biocompatible and biodegradable characteristics, but their visco-elastic properties limit their applicability, especially with respect to 3D bioprinting. In this study, we modified the naturally occurring extracellular matrix glycosaminoglycan hyaluronic acid (HA), in order to yield photo-crosslinkable hydrogels with increased mechanical stiffness and long-term stability, and with minimal decrease in cytocompatibility. Application of these tailor-made methacrylated hyaluronic acid (MeHA) gels for bone tissue engineering and 3D bioprinting was the subject of investigation. Visco-elastic properties of MeHA gels, measured by rheology and dynamic mechanical analysis, showed that irradiation of the hydrogels with UV light led to increased storage moduli and elastic moduli, indicating increasing gel rigidity. Subsequently, human bone marrow derived mesenchymal stromal cells (MSCs) were incorporated into MeHA hydrogels, and cell viability remained 64.4% after 21 days of culture. Osteogenic differentiation of MSCs occurred spontaneously in hydrogels with high concentrations of MeHA polymer, in absence of additional osteogenic stimuli. Addition of bone morphogenetic protein-2 (BMP-2) to the culture medium further increased osteogenic differentiation, as evidenced by increased matrix mineralisation. MeHA hydrogels demonstrated to be suitable for 3D bioprinting, and were printed into porous and anatomically shaped scaffolds. Taken together, photosensitive MeHA-based hydrogels fulfilled our criteria for cellular bioprinted bone constructs within a narrow window of concentration. PMID:28586346

  11. The potential of mangosteen (Garcinia mangostana) peel extract, combined with demineralized freeze-dried bovine bone xenograft, to reduce ridge resorption and alveolar bone regeneration in preserving the tooth extraction socket.

    PubMed

    Kresnoadi, Utari; Ariani, Maretaningtias Dwi; Djulaeha, Eha; Hendrijantini, Nike

    2017-01-01

    Following the extraction of a tooth, bone resorption can cause significant problems for a subsequent denture implant and restorative dentistry. Thus, the tooth extraction socket needs to be maintained to reduce the chance of any alveolar ridge bone resorption. The objective of this study is to determine whether the administration of mangosteen peel extracts (MPEs), combined with demineralized freeze-dried bovine bone xenograft (DFBBX) materials for tooth extraction socket preservation, could potentially reduce inflammation by decreased the expression of nuclear factor κβ (NfKb) and receptor activator of nuclear factor-κβ ligand (RANKL), to inhibit alveolar bone resorption, and increased of bone morphogenetic protein-2 (BMP2) expressions to accelerate alveolar bone regeneration. This study consists of several stages. First, a dosage of MPE combined with graft materials was applied to a preserved tooth extraction socket of a Cavia cobaya . Second, the C. cobaya was examined using immune histochemical expression of NfKb, RANKL, BMP2, as well as histology of osteoblasts and osteoclasts. The research was statistically analyzed, using an analysis of variance test and Tukey honest significant difference test. The results of this research were that it was determined that MPEs combined with graft materials on a preserved tooth extraction socket can reduce NfKb, RANK, and osteoclasts also increase of BMP2 and osteoblast. The induction of MPEs and DFBBX is effective in reducing inflammation, lowering osteoclasts, decreasing alveolar bone resorption, and also increasing BMP2 expression and alveolar bone regeneration.

  12. Activity of bone morphogenetic protein-7 after treatment at various temperatures: freezing vs. pasteurization vs. allograft.

    PubMed

    Takata, Munetomo; Sugimoto, Naotoshi; Yamamoto, Norio; Shirai, Toshiharu; Hayashi, Katsuhiro; Nishida, Hideji; Tanzawa, Yoshikazu; Kimura, Hiroaki; Miwa, Shinji; Takeuchi, Akihiko; Tsuchiya, Hiroyuki

    2011-12-01

    Insufficient bone union is the occasional complication of biomechanical reconstruction after malignant bone tumor resection using temperature treated tumor bearing bone; freezing, pasteurization, and autoclaving. Since bone morphogenetic protein (BMP) plays an important role in bone formation, we assessed the amount and activity of BMP preserved after several temperature treatments, including -196 and -73°C for 20 min, 60 and 100°C for 30 min, 60°C for 10h following -80°C for 12h as an allograft model, and 4°C as the control. The material extracted from the human femoral bone was treated, and the amount of BMP-7 was analyzed using an enzyme-linked immunosorbent assay. Then, the activity of recombinant human BMP-7 after the treatment was assessed using a bioassay with NIH3T3 cells and immunoblotting analysis to measure the amount of phospho-Smad, one of the signaling substrates that reflect the intracellular reaction of BMPs. Both experiments revealed that BMP-7 was significantly better preserved in the hypothermia groups. The percentages of the amount of BMP-7 in which the control group was set at 100% were 114%, 108%, 70%, 49%, and 53% in the -196, -73, 60, 100°C, and the allograft-model group, respectively. The percentages of the amount of phospho-Smad were 89%, 87%, 24%, 4.9%, and 14% in the -196, -73, 60, 100°C, and the allograft-model group, respectively. These results suggested that freezing possibly preserves osteoinductive ability than hyperthermia treatment. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Combination therapy of canine osteosarcoma with canine bone marrow stem cells, bone morphogenetic protein and carboplatin in an in vivo model.

    PubMed

    Rici, R E G; Will, S E A L; Luna, A C L; Melo, L F; Santos, A C; Rodrigues, R F; Leandro, R M; Maria, D A

    2018-05-20

    Osteosarcoma (OSA) is the most common malignant bone cancer in children and dogs. The therapeutic protocols adopted for dogs and humans are very similar, involving surgical options such as amputation. Besides surgical options, radiotherapy and chemotherapy also are adopted. However, hematologic, gastrointestinal and renal toxicity may occur because of chemotherapy treatments. Recent study clearly showed that mesenchymal stem cells (MSCs) combined with recombinant human bone morphogenetic protein (rhBMP-2) may be associated with decreases of the tumorigenic potential of canine OSA. The aim of this study was to analyse the efficacy of chemotherapy with carboplatin and rhBMP-2 with MSCs in a canine OSA in vivo model. Canine OSA cells were implanted in mice Balb-c/nude with MSCs, rhBMP-2 and carboplatin. Flow cytometry and PCR for markers involved in tumour suppression pathways were analysed. Results showed that the combination of MSCs and rhBMP-2 reduced tumour mass and infiltration of neoplastic cells in tissues more efficiently than carboplatin alone. Thus it was demonstrated that the use of rhBMP-2 and MSCs, in combination with conventional antineoplastic, may be an efficient treatment strategy. © 2018 John Wiley & Sons Ltd.

  14. Improvement of Implant Placement after Bone Augmentation of Severely Resorbed Maxillary Sinuses with 'Tent-Pole' Grafting Technique in Combination with rhBMP-2.

    PubMed

    Zhang, Qiao; Zhang, Li Li; Yang, Yang; Lin, Yi Zhen; Miron, Richard J; Zhang, Yu Feng

    To study the clinical effect of short implant placement using osteotome sinus floor elevation technique and tent-pole grafting technique with recombinant human bone morphogenetic protein 2 (rhBMP-2) in severely resorbed maxillary area. Eleven patients with insufficient bone height in the posterior maxillary area were included. According to the native bone height and crown height space (CHS), the patients were divided into two groups: immediate placement of short implants with simultaneous bone augmentation (group A, 5 patients) and delayed dental implant placement (4 to 6 months) after bone augmentation. The rhBMP-2 was added into a deproteinised bovine bone mineral (DBBM) bone grafting material to shorten the treatment procedure and enhance the final effect of bone augmentation in both groups. Tent-pole grafting technique was applied for vertical bone augmentation in group B (6 patients). The success rate of the implants placed was 100% in both groups. In group A, the short implants treatment was successful, with a vertical gain of 1.5 to 6.4 mm in bone height after 4 to 6 months. In group B, the tent-pole grafting procedure in combination with DBBM and rhBMP-2 increased vertical bone height between 3.1 and 8.1 mm, an optimistic and adequate increase for implant placement. This bone increase was maintained following implant placement and final crown placement in the maxillary region (3.5 to 7.3 mm). The tent-pole grafting technique was a viable alternative choice to lateral sinus floor elevation in cases with excessive CHS. The application of rhBMP-2 with a shortened treatment time demonstrated positive outcomes in sinus floor augmentation procedures.

  15. Dual growth factor delivery from biofunctionalized allografts: Sequential VEGF and BMP-2 release to stimulate allograft remodeling.

    PubMed

    Sharmin, Farzana; McDermott, Casey; Lieberman, Jay; Sanjay, Archana; Khan, Yusuf

    2017-05-01

    Autografts have been shown to stimulate osteogenesis, osteoclastogenesis, and angiogenesis, and subsequent rapid graft incorporation. Large structural allografts, however, suffer from limited new bone formation and remodeling, both of which are directly associated with clinical failure due to non-unions, late graft fractures, and infections, making it a priority to improve large structural allograft healing. We have previously shown the osteogenic ability of a polymer-coated allograft that delivers bone morphogenetic protein-2 both in vitro and in vivo through both burst release and sustained release kinetics. In this study, we have demonstrated largely sequential delivery of bone morphogenetic protein-2 and vascular endothelial growth factor from the same coated allograft. Release data showed that loading both growth factors onto a polymeric coating with two different techniques resulted in short-term (95% release within 2 weeks) and long-term (95% release within 5 weeks) delivery kinetics. We have also demonstrated how released VEGF, traditionally associated with angiogenesis, can also provide a stimulus for allograft remodeling via resorption. Bone marrow derived mononuclear cells were co-cultured with VEGF released from the coated allograft and showed a statistically significant (p < 0.05) and dose dependent increase in the number of tartrate-resistant acid phosphatase-positive multinucleated osteoclasts. Functionality of these osteoclasts was assessed quantitatively and qualitatively by evaluating resorption pit area from both osteo-assay plates and harvested bone. Data indicated a statistically significant higher resorption area from the cells exposed to VEGF released from the allografts over controls (p < 0.05). These results indicate that by using different loading protocols temporal control can be achieved when delivering multiple growth factors from a polymer-coated allograft. Further, released VEGF can also stimulate osteoclastogenesis that may enhance allograft incorporation, and thus mitigate long-term clinical complications. © 2017 Orthopedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1086-1095, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. Intervariability and intravariability of bone morphogenetic proteins in commercially available demineralized bone matrix products.

    PubMed

    Bae, Hyun W; Zhao, Li; Kanim, Linda E A; Wong, Pamela; Delamarter, Rick B; Dawson, Edgar G

    2006-05-20

    Enzyme-linked immunosorbent assay was used to detect bone morphogenetic proteins (BMPs) 2, 4, and 7 in 9 commercially available ("off the shelf") demineralized bone matrix (DBM) product formulations using 3 different manufacturer's production lots of each DBM formulation. To evaluate and compare the quantity of BMPs among several different DBM formulations (inter-product variability), as well as examine the variability of these proteins in different production lots within the same DBM formulation (intra-product variability). DBMs are commonly used to augment available bone graft in spinal fusion procedures. Surgeons are presented with an ever-increasing variety of commercially available human DBMs from which to choose. Yet, there is limited information on a specific DBM product's osteoinductive efficacy, potency, and constancy. There were protein extracts from each DBM sample separately dialyzed 4 times against distilled water at 4 degrees C for 48 hours. The amount of BMP-2, BMP-4, and BMP-7 was determined using enzyme-linked immunosorbent assay. RESULTS.: The concentrations of detected BMP-2 and BMP-7 were low for all DBM formulations, only nanograms of BMP were extracted from each gram of DBM (20.2-120.6 ng BMP-2/g DBM product; 54.2-226.8 ng BMP-7/g DBM). The variability of BMP concentrations among different lots of the same DBM formulation, intra-product variability, was higher than the variability of concentrations among different DBM formulations, inter-product variability (coefficient of variation range BMP-2 [16.34% to 76.01%], P < 0.01; BMP-7 [3.71% to 82.08%], P < 0.001). BMP-4 was undetectable. The relative quantities of BMPs in DBMs are low, in the order of 1 x 10(-9) g of BMP/g of DBM. There is higher variability in concentration of BMPs among 3 different lots of the same DBM formulation than among different DBM formulations. This variability questions DBM products' reliability and, possibly, efficacy in providing consistent osteoinduction.

  17. Transdifferentiation of adipocytes to osteoblasts: potential for orthopaedic treatment.

    PubMed

    Lin, Daphne P L; Dass, Crispin R

    2018-03-01

    As both adipocytes and osteoblasts originate from the same pool of mesenchymal stem cells, increasing clinical evidence has emerged of the plasticity between the two lineages. For instance, the downregulation of osteoblast differentiation and upregulation of adipogenesis are common features of conditions such as multiple myeloma, obesity and drug-induced bone loss in diabetes mellitus. However, despite in-vitro and in-vivo observations of adipocyte transdifferentiation into osteoblasts, little is known of the underlying mechanisms. This review summarises the current knowledge of this particular transdifferentiation process whereby the Wnt/β-catenin signalling pathway and Runx2 overexpression have been postulated to play a critical role. Furthermore, due to the possibility of a novel therapy in the treatment of bone conditions, a number of agents with the potential to induce adipo-to-osteoblast transdifferentiation have been investigated such as all-trans retinoic acid, bone morphogenetic protein-9 and vascular endothelial growth factor. © 2018 Royal Pharmaceutical Society.

  18. Development of a Model System to Evaluate Local Recurrence in Osteosarcoma and Assessment of the Effects of Bone Morphogenetic Protein-2.

    PubMed

    Geller, David S; Singh, Michael Y; Zhang, Wendong; Gill, Jonathan; Roth, Michael E; Kim, Mimi Y; Xie, Xianhong; Singh, Christopher K; Dorfman, Howard D; Villanueva-Siles, Esperanza; Park, Amy; Piperdi, Sajida; Gorlick, Richard

    2015-07-01

    It is increasingly relevant to better define what constitutes an adequate surgical margin in an effort to improve reconstructive longevity and functional outcomes following osteosarcoma surgery. In addition, nonunion remains a challenging problem in some patients following allograft reconstruction. Bone morphogenetic protein-2 (BMP-2) could enhance osseous union, but has been historically avoided due to concerns that it may promote tumor recurrence. An orthotopic xenograft murine model was utilized to describe the natural temporal course of osteosarcoma growth. Tumors were treated either with surgery alone, surgery and single-agent chemotherapy, or surgery and dual-agent chemotherapy to assess the relationship between surgical margin and local recurrence. The effect of BMP-2 on local recurrence was similarly assessed. Osteosarcoma tumor growth was categorized into reproducible phases. Margins greater than 997 μm resulted in local control following surgery alone. Margins greater than 36 μm resulted in local control following surgery and single-agent chemotherapy. Margins greater than 12 μm resulted in local control following surgery and dual-agent chemotherapy. The application of exogenous BMP-2 does not confer an increased risk of local recurrence. This model reliably reproduces the clinical, radiographic, and surgical conditions encountered in human osteosarcoma. It successfully incorporates relevant chemotherapy, further paralleling the human experience. Surgical margins required to achieve local control in osteosarcoma can be reduced using single-agent chemotherapy and further decreased using dual-agent chemotherapy. The application of BMP-2 does not increase local recurrence in this model. ©2014 American Association for Cancer Research.

  19. Effect of Escherichia coli-produced recombinant human bone morphogenetic protein 2 on the regeneration of canine segmental ulnar defects.

    PubMed

    Harada, Yasuji; Itoi, Takamasa; Wakitani, Shigeyuki; Irie, Hiroyuki; Sakamoto, Michiko; Zhao, Dongwei; Nezu, Yoshinori; Yogo, Takuya; Hara, Yasushi; Tagawa, Masahiro

    2012-07-01

    Because bone morphogenetic protein 2 gene transfected Escherichia coli (E-BMP-2) produce recombinant human BMP-2 (rhBMP-2) more efficiently than mammalian cells (Chinese hamster ovary [CHO]-BMP-2), they may be a more cost-effective source of rhBMP-2 for clinical use. However, use of E-BMP-2 for regenerating long bones in large animals has not been reported. In the current study, we evaluated the healing efficacy of E-BMP-2 in a canine model. We created 2.5-cm critical-size segmental ulnar defects in test animals, then implanted E-BMP-2 and 700 mg of artificial bone (beta-tricalcium phosphate; β-TCP) into the wounds. We examined the differential effects of 5 E-BMP-2 treatments (0, 35, 140, 560, and 2240 μg) across 5 experimental groups (control, BMP35, BMP140, BMP560, and BMP2240). Radiography and computed tomography were used to observe the regeneration process. The groups in which higher doses of E-BMP-2 were administered (BMP560 and BMP2240) displayed more pronounced bone regeneration; the regenerated tissues connected to the host bone, and the cross-sectional areas of the regenerated bone were larger than those of the originals. The groups in which lower doses of E-BMP-2 were administered (BMP35 and BMP140) experienced relatively less bone regeneration; furthermore, the regenerated tissues failed to connect to the host bone. In these groups, the cross-sectional areas of the regenerated bone were equal to or smaller than those of the originals. No regeneration was observed in the control group. These findings suggest that, like CHO-BMP-2, E-BMP-2 can be used for the regeneration of large defects in long bones and that its clinical use might decrease the cost of bone regeneration treatments.

  20. Bone Morphogenetic Protein-7 Enhances Degradation of Osteoinductive Bioceramic Implants in an Ectopic Model

    PubMed Central

    Klünter, Tim; Schulz, Peter; Deisinger, Ulrike; Diez, Claudius; Waiss, Waltraud; Kirschneck, Christian; Reichert, Torsten E.; Detsch, Rainer

    2017-01-01

    Background: The aim of the present study was to evaluate the degradation pattern of highly porous bioceramics as well as the bone formation in presence of bone morphogenetic protein 7 (BMP-7) in an ectopic site. Methods: Novel calcium phosphate ceramic cylinders sintered at 1,300°C with a total porosity of 92–94 vol%, 45 pores per inch, and sized 15 mm (Ø) × 5 mm were grafted on the musculus latissimus dorsi bilaterally in 10 Göttingen minipigs: group I (n = 5): hydroxyapatite (HA) versus biphasic calcium phosphate (BCP), a mixture of HA and tricalcium phosphate (TCP) in a ratio of 60/40 wt%; group II (n = 5): TCP versus BCP. A test side was supplied in situ with 250 μg BMP-7. Fluorochrome bone labeling and computed tomography were performed in vivo. Specimens were evaluated 14 weeks after surgery by environmental scanning electron microscopy, fluorescence microscopy, tartrate-resistant acid phosphatase, and pentachrome staining. Results: Bone formation was enhanced in the presence of BMP-7 in all ceramics (P = 0.001). Small spots of newly formed bone were observed in all implants in the absence of BMP-7. Degradation of HA and BCP was enhanced in the presence of BMP-7 (P = 0.001). In those ceramics, osteoclasts were observed. TCP ceramics were almost completely degraded independently of the effect of BMP-7 after 14 weeks (P = 0.76), osteoclasts were not observed. Conclusions: BMP-7 enhanced bone formation and degradation of HA and BCP ceramics via osteoclast resorption. TCP degraded via dissolution. All ceramics were osteoinductive. Novel degradable HA and BCP ceramics in the presence of BMP-7 are promising bone substitutes in the growing individual. PMID:28740783

  1. Collagen I derived recombinant protein microspheres as novel delivery vehicles for bone morphogenetic protein-2.

    PubMed

    Mumcuoglu, Didem; de Miguel, Laura; Jekhmane, Shehrazade; Siverino, Claudia; Nickel, Joachim; Mueller, Thomas D; van Leeuwen, Johannes P; van Osch, Gerjo J; Kluijtmans, Sebastiaan G

    2018-03-01

    Bone morphogenetic protein-2 (BMP-2) is a powerful osteoinductive protein; however, there is a need for the development of a safe and efficient BMP-2 release system for bone regeneration therapies. Recombinant extracellular matrix proteins are promising next generation biomaterials since the proteins are well-defined, reproducible and can be tailored for specific applications. In this study, we have developed a novel and versatile BMP-2 delivery system using microspheres from a recombinant protein based on human collagen I (RCP). In general, a two-phase release pattern was observed while the majority of BMP-2 was retained in the microspheres for at least two weeks. Among different parameters studied, the crosslinking and the size of the RCP microspheres changed the in vitro BMP-2 release kinetics significantly. Increasing the chemical crosslinking (hexamethylene diisocyanide) degree decreased the amount of initial burst release (24h) from 23% to 17%. Crosslinking by dehydrothermal treatment further decreased the burst release to 11%. Interestingly, the 50 and 72μm-sized spheres showed a significant decrease in the burst release compared to 207-μm sized spheres. Very importantly, using a reporter cell line, the released BMP-2 was shown to be bioactive. SPR data showed that N-terminal sequence of BMP-2 was important for the binding and retention of BMP-2 and suggested the presence of a specific binding epitope on RCP (K D : 1.2nM). This study demonstrated that the presented RCP microspheres are promising versatile BMP-2 delivery vehicles. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Thyroid Hormone-Induced Hypertrophy in Mesenchymal Stem Cell Chondrogenesis Is Mediated by Bone Morphogenetic Protein-4

    PubMed Central

    Karl, Alexandra; Olbrich, Norman; Pfeifer, Christian; Berner, Arne; Zellner, Johannes; Kujat, Richard; Angele, Peter; Nerlich, Michael

    2014-01-01

    Chondrogenic differentiating mesenchymal stem cells (MSCs) express markers of hypertrophic growth plate chondrocytes. As hypertrophic cartilage undergoes ossification, this is a concern for the application of MSCs in articular cartilage tissue engineering. To identify mechanisms that elicit this phenomenon, we used an in vitro hypertrophy model of chondrifying MSCs for differential gene expression analysis and functional experiments with the focus on bone morphogenetic protein (BMP) signaling. Hypertrophy was induced in chondrogenic MSC pellet cultures by transforming growth factor β (TGFβ) and dexamethasone withdrawal and addition of triiodothyronine. Differential gene expression analysis of BMPs and their receptors was performed. Based on these results, the in vitro hypertrophy model was used to investigate the effect of recombinant BMP4 and the BMP inhibitor Noggin. The enhancement of hypertrophy could be shown clearly by an increased cell size, alkaline phosphatase activity, and collagen type X deposition. Upon induction of hypertrophy, BMP4 and the BMP receptor 1B were upregulated. Addition of BMP4 further enhanced hypertrophy in the absence, but not in the presence of TGFβ and dexamethasone. Thyroid hormone induced hypertrophy by upregulation of BMP4 and this induced enhancement of hypertrophy could be blocked by the BMP antagonist Noggin. BMP signaling is an important modulator of the late differentiation stages in MSC chondrogenesis and the thyroid hormone induces this pathway. As cartilage tissue engineering constructs will be exposed to this factor in vivo, this study provides important insight into the biology of MSC-based cartilage. Furthermore, the possibility to engineer hypertrophic cartilage may be helpful for critical bone defect repair. PMID:23937304

  3. Evaluation of a thiolated chitosan scaffold for local delivery of BMP-2 for osteogenic differentiation and ectopic bone formation.

    PubMed

    Bae, In-Ho; Jeong, Byung-Chul; Kook, Min-Suk; Kim, Sun-Hun; Koh, Jeong-Tae

    2013-01-01

    Thiolated chitosan (Thio-CS) is a well-established pharmaceutical excipient for drug delivery. However, its use as a scaffold for bone formation has not been investigated. The aim of this study was to evaluate the potential of Thio-CS in bone morphogenetic protein-2 (BMP-2) delivery and bone formation. In vitro study showed that BMP-2 interacted with the Thio-CS and did not affect the swelling behavior. The release kinetics of BMP-2 from the Thio-CS was slightly delayed (70%) within 7 days compared with that from collagen gel (Col-gel, 85%), which is widely used in BMP-2 delivery. The BMP-2 released from Thio-CS increased osteoblastic cell differentiation but did not show any cytotoxicity until 21 days. Analysis of the in vivo ectopic bone formation at 4 weeks of posttransplantation showed that use of Thio-CS for BMP-2 delivery induced more bone formation to a greater extent (1.8 fold) than that of Col-gel. However, bone mineral density in both bones was equivalent, regardless of Thio-CS or Col-gel carrier. Taken together, Thio-CS system might be useful for delivering osteogenic protein BMP-2 and present a promising bone regeneration strategy.

  4. Longitudinal in vivo evaluation of bone regeneration by combined measurement of multi-pinhole SPECT and micro-CT for tissue engineering

    NASA Astrophysics Data System (ADS)

    Lienemann, Philipp S.; Metzger, Stéphanie; Kiveliö, Anna-Sofia; Blanc, Alain; Papageorgiou, Panagiota; Astolfo, Alberto; Pinzer, Bernd R.; Cinelli, Paolo; Weber, Franz E.; Schibli, Roger; Béhé, Martin; Ehrbar, Martin

    2015-05-01

    Over the last decades, great strides were made in the development of novel implants for the treatment of bone defects. The increasing versatility and complexity of these implant designs request for concurrent advances in means to assess in vivo the course of induced bone formation in preclinical models. Since its discovery, micro-computed tomography (micro-CT) has excelled as powerful high-resolution technique for non-invasive assessment of newly formed bone tissue. However, micro-CT fails to provide spatiotemporal information on biological processes ongoing during bone regeneration. Conversely, due to the versatile applicability and cost-effectiveness, single photon emission computed tomography (SPECT) would be an ideal technique for assessing such biological processes with high sensitivity and for nuclear imaging comparably high resolution (<1 mm). Herein, we employ modular designed poly(ethylene glycol)-based hydrogels that release bone morphogenetic protein to guide the healing of critical sized calvarial bone defects. By combined in vivo longitudinal multi-pinhole SPECT and micro-CT evaluations we determine the spatiotemporal course of bone formation and remodeling within this synthetic hydrogel implant. End point evaluations by high resolution micro-CT and histological evaluation confirm the value of this approach to follow and optimize bone-inducing biomaterials.

  5. Ubiquitous overexpression of Hey1 transcription factor leads to osteopenia and chondrocyte hypertrophy in bone.

    PubMed

    Salie, Rishard; Kneissel, Michaela; Vukevic, Mirko; Zamurovic, Natasa; Kramer, Ina; Evans, Glenda; Gerwin, Nicole; Mueller, Matthias; Kinzel, Bernd; Susa, Mira

    2010-03-01

    The transcription factor Hey1, a known Notch target gene of the HES family, has recently been described as a target gene of bone morphogenetic protein-2 (BMP-2) during osteoblastic differentiation in vitro. As the role of Hey1 in skeletal physiology is unknown, we analyzed bones of mice ubiquitously lacking or overexpressing Hey1. This strategy enabled us to evaluate whether Hey1 modulation in the whole organism could serve as a drug or antibody target for therapy of diseases associated with bone loss. Hey1 deficiency resulted in modest osteopenia in vivo and increased number and activity of osteoclasts generated ex vivo. Hey1 overexpression resulted in distinct progressive osteopenia and inhibition of osteoblasts ex vivo, an effect apparently dominant to a mild inhibition of osteoclasts. In both Hey1 deficient and overexpressing mice, males were less affected than females and skeleton was not affected during development. Bone histomorphometry did not reveal major changes in animals at 20 weeks, suggesting that modulation had occurred before. Adult Hey1 transgenics also displayed increased type X collagen expression and an enlarged hypertrophic zone in the growth plate. Taken together, our data suggest that ubiquitous in vivo Hey1 regulation affects osteoblasts, osteoclasts and chondrocytes. Due to the complex role of Hey1 in bone, inhibition of Hey1 does not appear to be a straightforward therapeutic strategy to increase the bone mass.

  6. Demineralized bone matrix fibers formable as general and custom 3D printed mold-based implants for promoting bone regeneration.

    PubMed

    Rodriguez, Rudy U; Kemper, Nathan; Breathwaite, Erick; Dutta, Sucharita M; Hsu, Erin L; Hsu, Wellington K; Francis, Michael P

    2016-07-26

    Bone repair frequently requires time-consuming implant construction, particularly when using un-formed implants with poor handling properties. We therefore developed osteoinductive, micro-fibrous surface patterned demineralized bone matrix (DBM) fibers for engineering both defect-matched and general three-dimensional implants. Implant molds were filled with demineralized human cortical bone fibers there were compressed and lyophilized, forming mechanically strong shaped DBM scaffolds. Enzyme linked immunosorbent assays and mass spectrometry confirmed that DBM fibers contained abundant osteogenic growth factors (bone morphogenetic proteins, insulin-like growth factor-I) and extracellular matrix proteins. Mercury porosimetry and mechanical testing showed interconnected pores within the mechanically stable, custom DBM fiber scaffolds. Mesenchymal stem cells readily attached to the DBM and showed increasing metabolic activity over time. DBM fibers further increased alkaline phosphatase activity in C2C12 cells. In vivo, DBM implants elicited osteoinductive potential in a mouse muscle pouch, and also promoted spine fusion in a rat arthrodesis model. DBM fibers can be engineered into custom-shaped, osteoinductive and osteoconductive implants with potential for repairing osseous defects with precise fitment, potentially reducing operating time. By providing pre-formed and custom implants, this regenerative allograft may improve patient outcomes following surgical bone repair, while further advancing personalized orthopedic and craniomaxillofacial medicine using three-dimensional-printed tissue molds.

  7. Mechanisms of Lipid Accumulation in the Bone Morphogenetic Protein Receptor Type 2 Mutant Right Ventricle

    PubMed Central

    Brittain, Evan L.; Fessel, Joshua P.; Penner, Niki; Atkinson, James; Funke, Mitch; Grueter, Carrie; Jerome, W. Gray; Freeman, Michael; Newman, John H.; West, James; Hemnes, Anna R.

    2016-01-01

    Rationale: In heritable pulmonary arterial hypertension with germline mutation in the bone morphogenetic protein receptor type 2 (BMPR2) gene, right ventricle (RV) dysfunction is associated with RV lipotoxicity; however, the underlying mechanism for lipid accumulation is not known. Objectives: We hypothesized that lipid accumulation in cardiomyocytes with BMPR2 mutation occurs owing to alterations in lipid transport and impaired fatty acid oxidation (FAO), which is exacerbated by a high-lipid (Western) diet (WD). Methods: We used a transgenic mouse model of pulmonary arterial hypertension with mutant BMPR2 and generated a cardiomyocyte cell line with BMPR2 mutation. Electron microscopy and metabolomic analysis were performed on mouse RVs. Measurements and Main Results: By metabolomics analysis, we found an increase in long-chain fatty acids in BMPR2 mutant mouse RVs compared with controls, which correlated with cardiac index. BMPR2-mutant cardiomyocytes had increased lipid compared with controls. Direct measurement of FAO in the WD-fed BMPR2-mutant RV showed impaired palmitate-linked oxygen consumption, and metabolomics analysis showed reduced indices of FAO. Using both mutant BMPR2 mouse RVs and cardiomyocytes, we found an increase in the uptake of 14C-palmitate and fatty acid transporter CD36 that was further exacerbated by WD. Conclusions: Taken together, our data suggest that impaired FAO and increased expression of the lipid transporter CD36 are key mechanisms underlying lipid deposition in the BMPR2-mutant RV, which are exacerbated in the presence of dietary lipids. These findings suggest important features leading to RV lipotoxicity in pulmonary arterial hypertension and may point to novel areas of therapeutic intervention. PMID:27077479

  8. Bone Morphogenetic Protein Regulation of Enteric Neuronal Phenotypic Diversity: Relationship to Timing of Cell Cycle Exit

    PubMed Central

    Chalazonitis, Alcmène; Pham, Tuan.D.; Li, Zhishan; Roman, Daniel; Guha, Udayan; Gomes, William; Kan, Lixin; Kessler, John A.; Gershon, Michael D.

    2008-01-01

    The effects of bone morphogenetic protein (BMP) signaling on enteric neuron development were examined in transgenic mice over expressing either the BMP inhibitor, noggin, or BMP4 under control of the neuron specific enolase (NSE) promoter. Noggin antagonism of BMP signaling increased total numbers of enteric neurons and those of subpopulations derived from precursors that exit the cell cycle early in neurogenesis (serotonin, calretinin, calbindin). In contrast, noggin overexpression decreased numbers of neurons derived from precursors that exit the cell cycle late (γ-aminobutyric acid, tyrosine hydroxylase [TH], dopamine transporter, calcitonin gene related peptide, TrkC). Numbers of TH- and TrkC-expressing neurons were increased by overexpression of BMP4. These observations are consistent with the idea that phenotypic expression in the enteric nervous system (ENS) is determined, in part, by the number of proliferative divisions neuronal precursors undergo before their terminal mitosis. BMP signaling may thus regulate enteric neuronal phenotypic diversity by promoting the exit of precursors from the cell cycle. BMP2 increased the numbers of TH- and TrkC-expressing neurons developing in vitro from immunoselected enteric crest-derived precursors; BMP signaling may thus also specify or promote the development of dopaminergic TrkC/NT-3-dependent neurons. The developmental defects in the ENS of noggin overexpressing mice caused a relatively mild disturbance of motility (irregular rapid transit and increased stool frequency, weight, and water content). Although the function of the gut thus displays a remarkable tolerance for ENS defects, subtle functional abnormalities in motility or secretion may arise when ENS defects short of aganglionosis occur during development. PMID:18537141

  9. Bone morphogenic protein: an elixir for bone grafting--a review.

    PubMed

    Shah, Prasun; Keppler, Louis; Rutkowski, James

    2012-12-01

    Bone morphogenetic proteins (BMPs) are multifunctional growth factors that belong to the transforming growth factor beta superfamily. This literature review focuses on the molecular biology of BMPs, their mechanism of action, and subsequent applications. It also discusses uses of BMPs in the fields of dentistry and orthopedics, research on methods of delivering BMPs, and their role in tissue regeneration. BMP has positive effects on bone grafts, and their calculated and timely use with other growth factors can provide extraordinary results in fractured or nonhealing bones. Use of BMP introduces new applications in the field of implantology and bone grafting. This review touches on a few unknown facts about BMP and this ever-changing field of research to improve human life.

  10. Adenoviral Mediated Expression of BMP2 by Bone Marrow Stromal Cells Cultured in 3D Copolymer Scaffolds Enhances Bone Formation.

    PubMed

    Sharma, Sunita; Sapkota, Dipak; Xue, Ying; Sun, Yang; Finne-Wistrand, Anna; Bruland, Ove; Mustafa, Kamal

    2016-01-01

    Selection of appropriate osteoinductive growth factors, suitable delivery method and proper supportive scaffold are critical for a successful outcome in bone tissue engineering using bone marrow stromal cells (BMSC). This study examined the molecular and functional effect of a combination of adenoviral mediated expression of bone morphogenetic protein-2 (BMP2) in BMSC and recently developed and characterized, biodegradable Poly(L-lactide-co-є-caprolactone){poly(LLA-co-CL)}scaffolds in osteogenic molecular changes and ectopic bone formation by using in vitro and in vivo approaches. Pathway-focused custom PCR array, validation using TaqMan based quantitative RT-PCR (qRT-PCR) and ALP staining showed significant up-regulation of several osteogenic and angiogenic molecules, including ALPL and RUNX2 in ad-BMP2 BMSC group grown in poly(LLA-co-CL) scaffolds both at 3 and 14 days. Micro CT and histological analyses of the subcutaneously implanted scaffolds in NOD/SCID mice revealed significantly increased radiopaque areas, percentage bone volume and formation of vital bone in ad-BMP2 scaffolds as compared to the control groups both at 2 and 8 weeks. The increased bone formation in the ad-BMP2 group in vivo was paralleled at the molecular level with concomitant over-expression of a number of osteogenic and angiogenic genes including ALPL, RUNX2, SPP1, ANGPT1. The increased bone formation in ad-BMP2 explants was not found to be associated with enhanced endochondral activity as evidenced by qRT-PCR (SOX9 and FGF2) and Safranin O staining. Taken together, combination of adenoviral mediated BMP-2 expression in BMSC grown in the newly developed poly(LLA-co-CL) scaffolds induced expression of osteogenic markers and enhanced bone formation in vivo.

  11. Systemically administered rhBMP-2 promotes MSC activity and reverses bone and cartilage loss in osteopenic mice.

    PubMed

    Turgeman, Gadi; Zilberman, Yoram; Zhou, Shuanhu; Kelly, Pam; Moutsatsos, Ioannis K; Kharode, Yogendra P; Borella, Luis E; Bex, Frederick J; Komm, Barry S; Bodine, Peter V N; Gazit, Dan

    2002-01-01

    Osteoporosis is a disease manifested in drastic bone loss resulting in osteopenia and high risk for fractures. This disease is generally divided into two subtypes. The first, post-menopausal (type I) osteoporosis, is primarily related to estrogen deficiency. The second, senile (type II) osteoporosis, is mostly related to aging. Decreased bone formation, as well as increased bone resorption and turnover, are thought to play roles in the pathophysiology of both types of osteoporosis. In this study, we demonstrate in murine models for both type I (estrogen deficiency) and type II (senile) osteopenia/osteoporosis that reduced bone formation is related to a decrease in adult mesenchymal stem cell (AMSC) number, osteogenic activity, and proliferation. Decreased proliferation is coupled with increased apoptosis in AMSC cultures obtained from osteopenic mice. Recombinant human bone morphogenetic protein (rhBMP-2) is a highly osteoinductive protein, promoting osteogenic differentiation of AMSCs. Systemic intra-peritoneal (i.p.) injections of rhBMP-2 into osteopenic mice were able to reverse this phenotype in the bones of these animals. Moreover, this change in bone mass was coupled to an increase in AMSCs numbers, osteogenic activity, and proliferation as well as a decrease in apoptosis. Bone formation activity was increased as well. However, the magnitude of this response to rhBMP-2 varied among different stains of mice. In old osteopenic BALB/c male mice (type II osteoporosis model), rhBMP-2 systemic treatment also restored both articular and epiphyseal cartilage width to the levels seen in young mice. In summary, our study shows that AMSCs are a good target for systemically active anabolic compounds like rhBMP-2. Copyright 2002 Wiley-Liss, Inc.

  12. Interaction between bone marrow stromal cells and neuroblastoma cells leads to a VEGFA-mediated osteoblastogenesis

    PubMed Central

    HaDuong, Josephine H.; Blavier, Laurence; Baniwal, Sanjeev K.; Frenkel, Baruch; Malvar, Jemily; Punj, Vasu; Sposto, Richard; DeClerck, Yves A.

    2017-01-01

    The potential role of osteoblasts in bone and bone marrow (BM) metastases in neuroblastoma (NBL) remains unclear. In this study, we examined the effect of NBL cells on the osteoblastic differentiation of bone marrow-derived mesenchymal stromal cells (BMMSC). We show that the presence of NBL cells enhanced the osteoblastic differentiation of BMMSC driven by bone morphogenetic protein (BMP)-4, in the absence of any effect on NBL cell proliferation. Expression profiles of BMMSC driven towards osteoblastic differentiation revealed an increase in vascular endothelial growth factor A (Vegfa) expression in the presence of NBL cells. We demonstrated that NBL cells increased BMMSC-derived VEGFA mRNA and protein and that this was enhanced by BMP-4. However, in similar conditions, neither the addition of an mVEGFA blocking antibody nor exogenous recombinant (r) mVEGFA affected osteoblastic differentiation. In contrast, siRNA-mediated knock-down of VEGFA in BMMSC prevented osteoblastic differentiation in BMP-4-treated co-cultures, an effect that was not reversed in the presence of rmVEGFA. An analysis of murine bones injected with hNBL cells revealed an increase of mVEGFA producing cells near tumor cells concomitantly with an increase in Vegfa and Runx2 mRNA. This coincided with an increase in osteoclasts, in Rankl/Opg mRNA ratio and with the formation of osteolytic lesions. Thus NBL cells promote osteoblastogenesis in the BM by increasing VEGFA expression in BMMSC. Our study provides a new insight into the role of VEGFA in NBL metastases by pointing to the role of stroma-derived intracrine VEGFA in osteoblastogenesis. PMID:25648303

  13. Osteogenic and chondrogenic master genes expression is dependent on the Kir2.1 potassium channel through the bone morphogenetic protein pathway.

    PubMed

    Pini, Jonathan; Giuliano, Serena; Matonti, Julia; Simkin, Dina; Rouleau, Matthieu; Bendahhou, Saïd

    2018-05-29

    Andersen's syndrome is a rare disorder affecting muscle, heart, and bone, that is associated with mutations leading to a loss of function of the inwardly rectifying K + channel Kir2.1. While the Kir2.1 function can be anticipated in excitable cells by controlling the electrical activity, its role in non-excitable cells remains to be investigated. Using Andersen's syndrome induced Pluripotent Stem cells, we investigated the cellular and molecular events during the osteoblastic and chondrogenic differentiation that are affected by the loss of the Ik1 current. We show that loss of Kir2.1 channel function impairs both osteoblastic and chondrogenic processes through the down regulation master gene expression. This down regulation is due to an impairment of the bone morphogenetic proteins signaling pathway through de-phosphorylation of the Smad proteins. Restoring Kir2.1 channel function in Andersen's syndrome cells rescued master genes expression, and restored normal osteoblasts and chondrocytes behavior. Our results show that Kir2.1-mediated activity controls endochondral and intramembranous ossification signaling pathways. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  14. A polymorphism in a conserved posttranscriptional regulatory motif alters bone morphogenetic protein 2 (BMP2) RNA:protein interactions.

    PubMed

    Fritz, David T; Jiang, Shan; Xu, Junwang; Rogers, Melissa B

    2006-07-01

    The bone morphogenetic protein (BMP)2 gene has been genetically linked to osteoporosis and osteoarthritis. We have shown that the 3'-untranslated regions (UTR) of BMP2 genes from mammals to fishes are extraordinarily conserved. This indicates that the BMP2 3'-UTR is under stringent selective pressure. We present evidence that the conserved region is a strong posttranscriptional regulator of BMP2 expression. Polymorphisms in cis-regulatory elements have been proven to influence susceptibility to a growing number of diseases. A common single nucleotide polymorphism (SNP) disrupts a putative posttranscriptional regulatory motif, an AU-rich element, within the BMP2 3'-UTR. The affinity of specific proteins for the rs15705 SNP sequence differs from their affinity for the normal human sequence. More importantly, the in vitro decay rate of RNAs with the SNP is higher than that of RNAs with the normal sequence. Such changes in mRNA:protein interactions may influence the posttranscriptional mechanisms that control BMP2 gene expression. The consequent alterations in BMP2 protein levels may influence the development or physiology of bone or other BMP2-influenced tissues.

  15. Evaluation of implants coated with recombinant human bone morphogenetic protein-2 and vacuum-dried using the critical-size supraalveolar peri-implant defect model in dogs.

    PubMed

    Decker, John F; Lee, Jaebum; Cortella, Carlo Alberto; Polimeni, Giuseppe; Rohrer, Michael D; Wozney, John M; Hall, Jan; Susin, Cristiano; Wikesjö, Ulf M E

    2010-12-01

    Endosseous implants coated with recombinant human bone morphogenetic protein-2 (rhBMP-2) in a laboratory bench setting and air-dried induce relevant bone formation but also resident bone remodeling. Thus, the objective of this study is to evaluate the effect of implants fully or partially coated with rhBMP-2 and vacuum-dried using an industrial process on local bone formation and resident bone remodeling. Twelve male adult Hound Labrador mongrel dogs were used. Critical-size, supraalveolar, peri-implant defects received titanium porous oxide surface implants coated in their most coronal aspect with rhBMP-2 (coronal-load, six animals), or by immersion of the entire implant in a rhBMP-2 solution (soak-load, six animals) for a total of 30 μg rhBMP-2 per implant. All implants were vacuum-dried. The animals were sacrificed at 8 weeks for histometric evaluation. Clinical healing was unremarkable. Bone formation was not significantly affected by the rhBMP-2 application protocol. New bone height and area averaged (± SE) 3.2 ± 0.5 versus 3.6 ± 0.3 mm, and 2.3 ± 0.5 versus 2.6 ± 0.8 mm(2) for coronal-load and soak-load implants, respectively (P >0.05). The corresponding bone density and bone-implant contact registrations averaged 46.7% ± 5.8% versus 31.6% ± 4.4%, and 28% ± 5.6% versus 36.9% ± 3.4% (P >0.05). In contrast, resident bone remodeling was significantly influenced by the rhBMP-2 application protocol. Peri-implant bone density averaged 72.2% ± 2.1% for coronal-load versus 60.6% ± 4.7% for soak-load implants (P <0.05); the corresponding bone-implant contact averaged 70.7% ± 6.1% versus 47.2% ± 6.0% (P <0.05). Local application of rhBMP-2 and vacuum-drying using industrial process seems to be a viable technology to manufacture implants that support local bone formation and osseointegration. Coronal-load implants obviate resident bone remodeling without compromising local bone formation.

  16. Quality-of-Life Outcomes following Thoracolumbar and Lumbar Fusion with and without the Use of Recombinant Human Bone Morphogenetic Protein-2: Does Recombinant Human Bone Morphogenetic Protein-2 Make a Difference?

    PubMed Central

    Lubelski, Daniel; Alvin, Matthew D.; Torre-Healy, Andrew; Abdullah, Kalil G.; Nowacki, Amy S.; Whitmore, Robert G.; Steinmetz, Michael P.; Benzel, Edward C.; Mroz, Thomas E.

    2014-01-01

    Design Retrospective study. Objectives (1) To investigate the quality-of-life (QOL) outcomes in the population undergoing lumbar spine surgery with versus without recombinant human bone morphogenetic protein-2 (rhBMP-2); (2) to determine QOL outcomes for those patients who experience postoperative complications; and (3) to identify the effect of patient characteristics on postoperative QOL outcomes. Methods A retrospective review of QOL questionnaires, including the Patient Health Questionnaire-9, Patient Disability Questionnaire (PDQ), EuroQol-5D (EQ-5D), and quality of life-year (QALY), was performed for all patients who underwent thoracolumbar and lumbar fusion surgery with versus without rhBMP-2 between March 2008 and September 2010. Individual preoperative and postoperative QOL data were compared for each patient. Demographic factors and complications were reviewed. Results We identified 266 patients, including 60 with and 206 without rhBMP-2. Questionnaires were completed an average of 10.3 ± 5 months after surgery. For all measures, average scores improved postoperatively compared with preoperatively. No differences in postoperative QOL outcomes were identified between the rhBMP-2 and the control cohorts. Median annual household income was positively associated with EQ-5D and QALY. Compared with those without, patients with postoperative complications had fewer QOL improvements. Conclusions There was no difference in QOL outcomes in the rhBMP-2 compared with the control group. Socioeconomic status and postoperative complications affected QOL outcomes following surgery. The QOL questionnaires provide the clinician with information regarding the patients' self-perceived well-being and can be helpful in the selection of surgical candidates and for understanding the effectiveness of a given surgical procedure. PMID:25396105

  17. Homeobox protein MSX-1 inhibits expression of bone morphogenetic protein 2, bone morphogenetic protein 4, and lymphoid enhancer-binding factor 1 via Wnt/β-catenin signaling to prevent differentiation of dental mesenchymal cells during the late bell stage.

    PubMed

    Feng, Xiao-Yu; Wu, Xiao-Shan; Wang, Jin-Song; Zhang, Chun-Mei; Wang, Song-Lin

    2018-02-01

    Homeobox protein MSX-1 (hereafter referred to as MSX-1) is essential for early tooth-germ development. Tooth-germ development is arrested at bud stage in Msx1 knockout mice, which prompted us to study the functions of MSX-1 beyond this stage. Here, we investigated the roles of MSX-1 during late bell stage. Mesenchymal cells of the mandibular first molar were isolated from mice at embryonic day (E)17.5 and cultured in vitro. We determined the expression levels of β-catenin, bone morphogenetic protein 2 (Bmp2), Bmp4, and lymphoid enhancer-binding factor 1 (Lef1) after knockdown or overexpression of Msx1. Our findings suggest that knockdown of Msx1 promoted expression of Bmp2, Bmp4, and Lef1, resulting in elevated differentiation of odontoblasts, which was rescued by blocking the expression of these genes. In contrast, overexpression of Msx1 decreased the expression of Bmp2, Bmp4, and Lef1, leading to a reduction in odontoblast differentiation. The regulation of Bmp2, Bmp4, and Lef1 by Msx1 was mediated by the Wnt/β-catenin signaling pathway. Additionally, knockdown of Msx1 impaired cell proliferation and slowed S-phase progression, while overexpression of Msx1 also impaired cell proliferation and prolonged G1-phase progression. We therefore conclude that MSX-1 maintains cell proliferation by regulating transition of cells from G1-phase to S-phase and prevents odontoblast differentiation by inhibiting expression of Bmp2, Bmp4, and Lef1 at the late bell stage via the Wnt/β-catenin signaling pathway. © 2017 Eur J Oral Sci.

  18. Additively manufactured 3D porous Ti-6Al-4V constructs mimic trabecular bone structure and regulate osteoblast proliferation, differentiation and local factor production in a porosity and surface roughness dependent manner.

    PubMed

    Cheng, Alice; Humayun, Aiza; Cohen, David J; Boyan, Barbara D; Schwartz, Zvi

    2014-10-07

    Additive manufacturing by laser sintering is able to produce high resolution metal constructs for orthopedic and dental implants. In this study, we used a human trabecular bone template to design and manufacture Ti-6Al-4V constructs with varying porosity via laser sintering. Characterization of constructs revealed interconnected porosities ranging from 15-70% with compressive moduli of 2579-3693 MPa. These constructs with macro porosity were further surface-treated to create a desirable multi-scale micro-/nano-roughness, which has been shown to enhance the osseointegration process. Osteoblasts (MG63 cells) exhibited high viability when grown on the constructs. Proliferation (DNA) and alkaline phosphatase specific activity, an early differentiation marker, decreased as porosity increased, while osteocalcin, a late differentiation marker, as well as osteoprotegerin, vascular endothelial growth factor and bone morphogenetic proteins 2 and 4 increased with increasing porosity. Three-dimensional (3D) constructs with the highest porosity and surface modification supported the greatest osteoblast differentiation and local factor production. These results indicate that additively manufactured 3D porous constructs mimicking human trabecular bone and produced with additional surface treatment can be customized for increased osteoblast response. Increased factors for osteoblast maturation and differentiation on high porosity constructs suggest the enhanced performance of these surfaces for increasing osseointegration in vivo.

  19. Fabrication of a three-dimensional β-tricalcium-phosphate/gelatin containing chitosan-based nanoparticles for sustained release of bone morphogenetic protein-2: Implication for bone tissue engineering.

    PubMed

    Bastami, Farshid; Paknejad, Zahrasadat; Jafari, Maissa; Salehi, Majid; Rezai Rad, Maryam; Khojasteh, Arash

    2017-03-01

    Fabrication of an ideal scaffold having proper composition, physical structure and able to have sustained release of growth factors still is challenging for bone tissue engineering. Current study aimed to design an appropriate three-dimensional (3-D) scaffold with suitable physical characteristics, including proper compressive strength, degradation rate, porosity, and able to sustained release of bone morphogenetic protein-2 (BMP2), for bone tissue engineering. A highly porous 3-D β-tricalcium phosphate (β-TCP) scaffolds, inside of which two perpendicular canals were created, was fabricated using foam-casting technique. Then, scaffolds were coated with gelatin layer. Next, BMP2-loaded chitosan (CS) nanoparticles were dispersed into collagen hydrogel and filled into the scaffold canals. Physical characteristics of fabricated constructs were evaluated. Moreover, the capability of given construct for bone regeneration has been evaluated in vitro in interaction with human buccal fat pad-derived stem cells (hBFPSCs). The results showed that gelatin-coated TCP scaffold with rhBMP2 delivery system not only could act as a mechanically and biologically compatible framework, but also act as an osteoinductive graft by sustained delivering of rhBMP2 in a therapeutic window for differentiation of hBFPSCs towards the osteoblast lineage. The proposed scaffold model can be suggested for delivering of cells and other growth factors such as vascular endothelial growth factor (VEGF), alone or in combination, for future investigations. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Effects of LED phototherapy on bone defects grafted with MTA, bone morphogenetic proteins and guided bone regeneration: a Raman spectroscopic study.

    PubMed

    Pinheiro, Antonio L B; Soares, Luiz G P; Cangussú, Maria Cristina T; Santos, Nicole R S; Barbosa, Artur Felipe S; Silveira Júnior, Landulfo

    2012-09-01

    We studied peaks of calcium hydroxyapatite (CHA) and protein and lipid CH groups in defects grafted with mineral trioxide aggregate (MTA) treated or not with LED irradiation, bone morphogenetic proteins and guided bone regeneration. A total of 90 rats were divided into ten groups each of which was subdivided into three subgroups (evaluated at 15, 21 and 30 days after surgery). Defects were irradiated with LED light (wavelength 850 ± 10 nm) at 48-h intervals for 15 days. Raman readings were taken at the surface of the defects. There were no statistically significant differences in the CHA peaks among the nonirradiated defects at any of the experimental time-points. On the other hand, there were significant differences between the defects filled with blood clot and the irradiated defects at all time-points (p < 0.001, p = 0.02, p < 0.001). There were significant differences between the mean peak CHA in nonirradiated defects at all the experimental time-points (p < 0.01). The mean peak of the defects filled with blood clot was significantly different from that of the defects filled with MTA (p < 0.001). There were significant differences between the defects filled with blood clot and the irradiated defects (p < 0.001). The results of this study using Raman spectral analysis indicate that infrared LED light irradiation improves the deposition of CHA in healing bone grafted or not with MTA.

  1. The Osteogenesis Effect and Underlying Mechanisms of Local Delivery of gAPN in Extraction Sockets of Beagle Dogs

    PubMed Central

    Hu, Hongcheng; Pu, Yinfei; Lu, Songhe; Zhang, Kuo; Guo, Yuan; Lu, Hui; Li, Deli; Li, Xuefen; Li, Zichen; Wu, Yuwei; Tang, Zhihui

    2015-01-01

    A plastic and biodegradable bone substitute consists of poly (l-lactic-co-glycolic) acid and 30 wt % β-tricalcium phosphate has been previously fabricated, but its osteogenic capability required further improvement. We investigated the use of globular adiponectin (gAPN) as an anabolic agent for tissue-engineered bone using this scaffold. A qualitative analysis of the bone regeneration process was carried out using μCT and histological analysis 12 weeks after implantation. CBCT (Cone Beam Computed Tomography) superimposition was used to characterise the effect of the different treatments on bone formation. In this study, we also explored adiponectin’s (APN) influence on primary cultured human jaw bone marrow mesenchymal stem cells gene expressions involved in the osteogenesis. We found that composite scaffolds loaded with gAPN or bone morphogenetic protein 2 (BMP2) exhibited significantly increased bone formation and mineralisation following 12 weeks in the extraction sockets of beagle dogs, as well as enhanced expression of osteogenic markers. In vitro investigation revealed that APN also promoted osteoblast differentiation of primary cultured human jaw bone marrow mesenchymal stem cells (h-JBMMSCs), accompanied by increased activity of alkaline phosphatase, greater mineralisation, and production of the osteoblast-differentiated genes osteocalcin, bone sialoprotein and collagen type I, which was reversed by APPL1 siRNA. Therefore, the composite scaffold loaded with APN exhibited superior activity for guided bone regeneration compared with blank control or Bio-Oss® (a commercially available product). The composite scaffold with APN has significant potential for clinical applications in bone tissue engineering. PMID:26492241

  2. Effect of nano-hydroxyapatite on bone morphogenetic protein-2-induced hard tissue formation and dentin resorption on a dentin surface

    NASA Astrophysics Data System (ADS)

    Tamagawa, Hiroki; Tenkumo, Taichi; Sugaya, Tsutomu; Kawanami, Masamitsu

    2012-12-01

    AimThe purpose of this study was to evaluate the effects of the addition of nano-hydroxyapatite to a collagen membrane-carrier of recombinant human bone morphogenetic protein-2 (rhBMP-2) on hard tissue formation and dentin resorption on dentin surfaces in vivo. Materials and methodsNano-hydroxyapatite collagen composite (nHAC) membranes or collagen (C) membranes were each immersed in either 100 or 400 μg/ml rhBMP-2 and placed on dentin chips that were implanted into rat thigh muscle. The implants were analyzed at 2 or 4 weeks after surgery by histological observation and histomorphometric analysis. ResultsThe percentage of the hard tissue formed by each nHAC group was significantly higher than that formed by any of the C groups, except for that formed by the group loaded with 400 μg/ml rhBMP-2 at 4 weeks after implantation. No significant differences were observed in the percentage of dentin resorption between the nHAC groups and C groups at any stage or at any rhBMP-2 concentration. ConclusionThese findings showed that addition of nano-hydroxyapatite to a collagen membrane accelerated the formation of hard tissue induced by a low dose of rhBMP-2 on dentin surfaces at an early stage after implantation into rat thigh muscle, without increasing dentin resorption.

  3. (−)-Epigallocatechin gallate but not chlorogenic acid upregulates osteoprotegerin synthesis through regulation of bone morphogenetic protein-4 in osteoblasts

    PubMed Central

    Fujita, Kazuhiko; Otsuka, Takanobu; Yamamoto, Naohiro; Kainuma, Shingo; Ohguchi, Reou; Kawabata, Tetsu; Sakai, Go; Kuroyanagi, Gen; Matsushima-Nishiwaki, Rie; Kozawa, Osamu; Tokuda, Haruhiko

    2017-01-01

    Chlorogenic acid (CGA) is a primary phenolic component of coffee and (−)-epigallocatechin gallate (EGCG) is a primary flavonoid component of green tea, both of which have been documented to possess beneficial health properties. A previous study by the present authors demonstrated that p38 mitogen-activated protein kinase (MAPK) may be associated with osteoprotegerin synthesis stimulated by bone morphogenetic protein-4 (BMP-4) in osteoblast-like MC3T3-E1 cells. In the present study, the effects of CGA and EGCG on BMP-4-stimulated osteoprotegerin synthesis in MC3T3-E1 cells were investigated. It was observed that CGA had no effect on osteoprotegerin release stimulated by BMP-4, whereas EGCG significantly enhanced BMP-4-stimulated osteoprotegerin release (P=0.003). Levels of osteoprotegerin mRNA expression induced by BMP-4 were also significantly increased by EGCG (P=0.03). By contrast, EGCG had no significant effect on phosphorylation of Smad1 or p38 MAPK induced by BMP-4. In addition, EGCG had little effect on BMP-induced phosphorylation of p70 S6 kinase; however rapamycin, as an inhibitor of p70 S6 kinase, significantly suppressed osteoprotegerin release (P=0.007). These data suggest that EGCG but not CGA may upregulate the synthesis of osteoprotegerin induced by BMP-4 in osteoblasts. PMID:28672948

  4. (-)-Epigallocatechin gallate but not chlorogenic acid upregulates osteoprotegerin synthesis through regulation of bone morphogenetic protein-4 in osteoblasts.

    PubMed

    Fujita, Kazuhiko; Otsuka, Takanobu; Yamamoto, Naohiro; Kainuma, Shingo; Ohguchi, Reou; Kawabata, Tetsu; Sakai, Go; Kuroyanagi, Gen; Matsushima-Nishiwaki, Rie; Kozawa, Osamu; Tokuda, Haruhiko

    2017-07-01

    Chlorogenic acid (CGA) is a primary phenolic component of coffee and (-)-epigallocatechin gallate (EGCG) is a primary flavonoid component of green tea, both of which have been documented to possess beneficial health properties. A previous study by the present authors demonstrated that p38 mitogen-activated protein kinase (MAPK) may be associated with osteoprotegerin synthesis stimulated by bone morphogenetic protein-4 (BMP-4) in osteoblast-like MC3T3-E1 cells. In the present study, the effects of CGA and EGCG on BMP-4-stimulated osteoprotegerin synthesis in MC3T3-E1 cells were investigated. It was observed that CGA had no effect on osteoprotegerin release stimulated by BMP-4, whereas EGCG significantly enhanced BMP-4-stimulated osteoprotegerin release (P=0.003). Levels of osteoprotegerin mRNA expression induced by BMP-4 were also significantly increased by EGCG (P=0.03). By contrast, EGCG had no significant effect on phosphorylation of Smad1 or p38 MAPK induced by BMP-4. In addition, EGCG had little effect on BMP-induced phosphorylation of p70 S6 kinase; however rapamycin, as an inhibitor of p70 S6 kinase, significantly suppressed osteoprotegerin release (P=0.007). These data suggest that EGCG but not CGA may upregulate the synthesis of osteoprotegerin induced by BMP-4 in osteoblasts.

  5. Immunohistochemical response in rats of beta-tricalcium phosphate (TCP) with or without BMP-2 in the production of collagen matrix critical defects.

    PubMed

    Luvizuto, Eloá Rodrigues; de Oliveira, Júlio César Silva; Gomes-Ferreira, Pedro Henrique Silva; Pereira, Cassiano Costa Silva; Faverani, Leonardo Perez; Antoniali, Cristina; Okamoto, Roberta

    2017-04-01

    This study aimed to assess the biological response of BMP-2 (bone morphogenetic protein-2) in supplementation with β-tricalcium phosphate (TCP) as a carrier in the bone healing of surgical defects in rats' calvaria. A critical-size defect (5mm in diameter) was filled with β-TCP alone or added with that plus 5mg of BMP-2 at 5, 15, and 30 postoperative days. Histomorphometric and immunohistochemical (osteocalcin, collagen type I, and metalloproteinase-9) analysis was performed to assess the features of bone healing. Histological behavior and collagen type I labeling showed increased formation of the collagen matrix, leading to a higher percentage of newly formed bone and biomaterial for tissue and more total mineralization of pure TCP when compared to the other groups. The supplementation with BMP-2 promoted faster TCP remodeling; however, there was no statistically significant difference for the bone formed in both groups (P>0.05). Collagen-matrix formation and new bone formation reached maximum levels when the defects were filled with pure TCP, even exceeding the levels from BMP-2 supplementation. Copyright © 2017 Elsevier GmbH. All rights reserved.

  6. Effects of strontium ranelate on bone formation in the mid-palatal suture after rapid maxillary expansion

    PubMed Central

    Zhao, Shuya; Wang, Xuxia; Li, Na; Chen, Yun; Su, Yuran; Zhang, Jun

    2015-01-01

    Background The aim of this experimental study was to investigate the effects of strontium ranelate on bone regeneration in the mid-palatal suture in response to rapid maxillary expansion (RME). Methods Thirty-six male 6-week-old Wistar rats were randomly divided into three groups, ie, an expansion only (EO) group, an expansion plus strontium ranelate (SE) group, and a control group. An orthodontic appliance was set between the right and left upper molars of rats with an initial expansive force of 0.98 N. Rats in the SE group were administered strontium ranelate (600 mg/kg body weight) and then euthanized in batches on days 4, 7, and 10. Morphological changes in the mid-palatal suture were investigated using micro-computed tomography and hematoxylin and eosin staining after RME. Bone morphogenetic protein-2 expression in the suture was also examined to evaluate bone formation in the mid-palatal suture. Image-Pro Plus software was then used to determine the mean optical density of the immunohistochemical images. Analysis of variance was used for statistical evaluation at the P<0.05 level. Results With expansive force, the mid-palatal suture was expanded, but there was no statistically significant difference (P>0.05) between the SE and EO groups. The bone volume of the suture decreased after RME, but was higher in the SE group than in the EO group on days 7 and 10. Further, expression of bone morphogenetic protein-2 in the SE group was higher than in the other two groups (P<0.05). Conclusion Strontium ranelate may hasten new bone formation in the expanded mid-palatal suture, which may be therapeutically beneficial in prevention of relapse and shortening the retention period after RME. PMID:26056433

  7. Highly aligned porous Ti scaffold coated with bone morphogenetic protein-loaded silica/chitosan hybrid for enhanced bone regeneration.

    PubMed

    Jung, Hyun-Do; Yook, Se-Won; Han, Cheol-Min; Jang, Tae-Sik; Kim, Hyoun-Ee; Koh, Young-Hag; Estrin, Yuri

    2014-07-01

    Porous Ti has been widely investigated for orthopedic and dental applications on account of their ability to promote implant fixation via bone ingrowth into pores. In this study, highly aligned porous Ti scaffolds coated with a bone morphogenetic protein (BMP)-loaded silica/chitosan hybrid were produced, and their bone regeneration ability was evaluated by in vivo animal experiments. Reverse freeze casting allowed for the creation of highly aligned pores, resulting in a high compressive strength of 254 ± 21 MPa of the scaffolds at a porosity level of ∼51 vol %. In addition, a BMP-loaded silica/chitosan hybrid coating layer with a thickness of ∼1 μm was uniformly deposited on the porous Ti scaffold, which enabled the sustained release of the BMP over a prolonged period of time up to 26 days. The cumulative amount of the BMP released was ∼4 μg, which was much higher than that released from the specimen without a hybrid coating layer. In addition, the bone regeneration ability of the porous Ti scaffold with a BMP-loaded silica/chitosan coating layer was examined by in vivo animal testing using a rabbit calvarial defect model and compared with those of the as-produced porous Ti scaffold and porous Ti scaffold with a silica/chitosan coating layer. After 4 weeks of healing, the specimen coated with a BMP-loaded silica/chitosan hybrid showed a much higher bone regeneration volume (∼36%) than the as-produced specimen (∼15%) (p < 0.005) and even the specimen coated with a silica/chitosan hybrid (∼25%) (p < 0.05). © 2013 Wiley Periodicals, Inc.

  8. Bone Regeneration Using N-Methyl-2-pyrrolidone as an Enhancer for Recombinant Human Bone Morphogenetic Protein-2 in a Rabbit Sinus Augmentation Model

    PubMed Central

    Thoma, Daniel S.

    2017-01-01

    The aim of this study was to determine whether N-methyl-2-pyrrolidone (NMP) can decrease the dose of recombinant human bone morphogenetic protein-2 (rhBMP-2) in sinus augmentation of rabbits. In each of 15 rabbits, 2 sinuses were randomly grafted using 1 of 3 treatment modalities: (i) biphasic calcium phosphate (BCP; control), (ii) rhBMP-2-coated BCP (BMP), or (iii) rhBMP-2-coated BCP soaked in NMP solution (BMP/NMP). The rabbits were sacrificed 2 weeks postoperatively. Histologic and histomorphometric analyses were performed. Bone formation in all groups was predominantly located close to the access window and the lateral walls. Newly formed bone within the total augmented area (NBTA) was greatest in BMP/NMP (1.94 ± 0.69 mm2), followed by BMP (1.50 ± 0.72 mm2) and BCP (1.28 ± 0.52 mm2) (P > 0.05). In the center of the augmentation (NBROI_C) and the area close to the sinus membrane (NBROI_M), BMP/NMP produced the largest area of NB (NBROI_C: 0.10 ± 0.11 mm2; NBROI_M: 0.17 ± 0.08 mm2); the corresponding NB values for BCP were 0.05 ± 0.05 mm2 and 0.08 ± 0.09 mm2, respectively (P > 0.05 for all comparisons). The effect of NMP on bone regeneration was inconsistent between the specimens. Adding NMP as an adjunct to rhBMP-2-coated BCP produced inconsistent effects on bone regeneration, resulting in no significant benefit compared to controls. PMID:28680881

  9. Bone Regeneration Using N-Methyl-2-pyrrolidone as an Enhancer for Recombinant Human Bone Morphogenetic Protein-2 in a Rabbit Sinus Augmentation Model.

    PubMed

    Lim, Hyun-Chang; Thoma, Daniel S; Yoon, So-Ra; Cha, Jae-Kook; Lee, Jung-Seok; Jung, Ui-Won

    2017-01-01

    The aim of this study was to determine whether N-methyl-2-pyrrolidone (NMP) can decrease the dose of recombinant human bone morphogenetic protein-2 (rhBMP-2) in sinus augmentation of rabbits. In each of 15 rabbits, 2 sinuses were randomly grafted using 1 of 3 treatment modalities: (i) biphasic calcium phosphate (BCP; control), (ii) rhBMP-2-coated BCP (BMP), or (iii) rhBMP-2-coated BCP soaked in NMP solution (BMP/NMP). The rabbits were sacrificed 2 weeks postoperatively. Histologic and histomorphometric analyses were performed. Bone formation in all groups was predominantly located close to the access window and the lateral walls. Newly formed bone within the total augmented area (NB TA ) was greatest in BMP/NMP (1.94 ± 0.69 mm 2 ), followed by BMP (1.50 ± 0.72 mm 2 ) and BCP (1.28 ± 0.52 mm 2 ) ( P > 0.05). In the center of the augmentation (NB ROI_C ) and the area close to the sinus membrane (NB ROI_M ), BMP/NMP produced the largest area of NB (NB ROI_C : 0.10 ± 0.11 mm 2 ; NB ROI_M : 0.17 ± 0.08 mm 2 ); the corresponding NB values for BCP were 0.05 ± 0.05 mm 2 and 0.08 ± 0.09 mm 2 , respectively ( P > 0.05 for all comparisons). The effect of NMP on bone regeneration was inconsistent between the specimens. Adding NMP as an adjunct to rhBMP-2-coated BCP produced inconsistent effects on bone regeneration, resulting in no significant benefit compared to controls.

  10. Comparative study suggests that human bone morphogenetic proteins have no influence on the outcome of operative treatment of aseptic clavicle non-unions.

    PubMed

    von Rüden, Christian; Morgenstern, Mario; Friederichs, Jan; Augat, Peter; Hackl, Simon; Woltmann, Alexander; Bühren, Volker; Hierholzer, Christian

    2016-11-01

    The purpose of this study was to evaluate the clinical and radiological outcome following compression plate fixation in combination with autologous bone grafting, with and without additional application of recombinant human bone morphogenetic protein (rhBMP) for treatment of aseptic clavicle non-union. Between April 2004 and April 2015, 82 patients were treated for clavicle fracture and had developed aseptic clavicle non-union. Seventy-three out of 82 patients were available for follow-up at least one year after revision surgery; among them, 27 women and 46 men, with a median age of 49 (range, 19-86) years. Forty-five patients received compression plate osteosynthesis with autologous bone grafting, and 28 patients obtained compression plate fixation with autologous bone grafting and additional application of rhBMP-2 (3/28 patients) or rhBMP-7 (25/28 patients). Seventy out of 73 non-unions (96 %) healed within 12 months after revision surgery. Functional outcome according to the DASH Outcome Measure (with rhBMP, 33.16 ± 1.17 points; without rhBMP, 30.58 ± 2.12 points [mean ± SEM]; p = 0.81), non-union healing (p = 0.86), time interval between revision surgery and bone healing (p = 0.37), as well as post-operative complications, did not demonstrate relevant differences between the treatment groups and were not age-dependent. Functional and radiological results demonstrate that successful healing of aseptic clavicle non-union is dependent on radical resection of non-union tissue, restoration of length of the shoulder girdle and application of stable locking-plate osteosynthesis in combination with autologous bone grafting, but not dependent on application of additional rhBMP.

  11. Direct bone morphogenetic protein 2 and Indian hedgehog gene transfer for articular cartilage repair using bone marrow coagulates.

    PubMed

    Sieker, J T; Kunz, M; Weißenberger, M; Gilbert, F; Frey, S; Rudert, M; Steinert, A F

    2015-03-01

    Bone morphogenetic protein 2 (BMP-2, encoded by BMP2) and Indian hedgehog protein (IHH, encoded by IHH) are well known regulators of chondrogenesis and chondrogenic hypertrophy. Despite being a potent chondrogenic factor BMP-2 was observed to induce chondrocyte hypertrophy in osteoarthritis (OA), growth plate cartilage and adult mesenchymal stem cells (MSCs). IHH might induce chondrogenic differentiation through different intracellular signalling pathways without inducing subsequent chondrocyte hypertrophy. The primary objective of this study is to test the efficacy of direct BMP2 and IHH gene delivery via bone marrow coagulates to influence histological repair cartilage quality in vivo. Vector-laden autologous bone marrow coagulates with 10(11) adenoviral vector particles encoding BMP2, IHH or the Green fluorescent protein (GFP) were delivered to 3.2 mm osteochondral defects in the trochlea of rabbit knees. After 13 weeks the histological repair cartilage quality was assessed using the ICRS II scoring system and the type II collagen positive area. IHH treatment resulted in superior histological repair cartilage quality than GFP controls in all of the assessed parameters (with P < 0.05 in five of 14 assessed parameters). Results of BMP2 treatment varied substantially, including severe intralesional bone formation in two of six joints after 13 weeks. IHH gene transfer is effective to improve repair cartilage quality in vivo, whereas BMP2 treatment, carried the risk intralesional bone formation. Therefore IHH protein can be considered as an attractive alternative candidate growth factor for further preclinical research and development towards improved treatments for articular cartilage defects. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  12. Laser Sintered Porous Ti-6Al-4V Implants Stimulate Vertical Bone Growth.

    PubMed

    Cheng, Alice; Cohen, David J; Kahn, Adrian; Clohessy, Ryan M; Sahingur, Kaan; Newton, Joseph B; Hyzy, Sharon L; Boyan, Barbara D; Schwartz, Zvi

    2017-08-01

    The objective of this study was to examine the ability of 3D implants with trabecular-bone-inspired porosity and micro-/nano-rough surfaces to enhance vertical bone ingrowth. Porous Ti-6Al-4V constructs were fabricated via laser-sintering and processed to obtain micro-/nano-rough surfaces. Male and female human osteoblasts were seeded on constructs to analyze cell morphology and response. Implants were then placed on rat calvaria for 10 weeks to assess vertical bone ingrowth, mechanical stability and osseointegration. All osteoblasts showed higher levels of osteocalcin, osteoprotegerin, vascular endothelial growth factor and bone morphogenetic protein 2 on porous constructs compared to solid laser-sintered controls. Porous implants placed in vivo resulted in an average of 3.1 ± 0.6 mm 3 vertical bone growth and osseointegration within implant pores and had significantly higher pull-out strength values than solid implants. New bone formation and pull-out strength was not improved with the addition of demineralized bone matrix putty. Scanning electron images and histological results corroborated vertical bone growth. This study indicates that Ti-6Al-4V implants fabricated by additive manufacturing to have porosity based on trabecular bone and post-build processing to have micro-/nano-surface roughness can support vertical bone growth in vivo, and suggests that these implants may be used clinically to increase osseointegration in challenging patient cases.

  13. Osteoblast Menin Regulates Bone Mass in Vivo*

    PubMed Central

    Kanazawa, Ippei; Canaff, Lucie; Abi Rafeh, Jad; Angrula, Aarti; Li, Jingjing; Riddle, Ryan C.; Boraschi-Diaz, Iris; Komarova, Svetlana V.; Clemens, Thomas L.; Murshed, Monzur; Hendy, Geoffrey N.

    2015-01-01

    Menin, the product of the multiple endocrine neoplasia type 1 (Men1) tumor suppressor gene, mediates the cell proliferation and differentiation actions of transforming growth factor-β (TGF-β) ligand family members. In vitro, menin modulates osteoblastogenesis and osteoblast differentiation promoted and sustained by bone morphogenetic protein-2 (BMP-2) and TGF-β, respectively. To examine the in vivo function of menin in bone, we conditionally inactivated Men1 in mature osteoblasts by crossing osteocalcin (OC)-Cre mice with floxed Men1 (Men1f/f) mice to generate mice lacking menin in differentiating osteoblasts (OC-Cre;Men1f/f mice). These mice displayed significant reduction in bone mineral density, trabecular bone volume, and cortical bone thickness compared with control littermates. Osteoblast and osteoclast number as well as mineral apposition rate were significantly reduced, whereas osteocyte number was increased. Primary calvarial osteoblasts proliferated more quickly but had deficient mineral apposition and alkaline phosphatase activity. Although the mRNA expression of osteoblast marker and cyclin-dependent kinase inhibitor genes were all reduced, that of cyclin-dependent kinase, osteocyte marker, and pro-apoptotic genes were increased in isolated Men1 knock-out osteoblasts compared with controls. In contrast to the knock-out mice, transgenic mice overexpressing a human menin cDNA in osteoblasts driven by the 2.3-kb Col1a1 promoter, showed a gain of bone mass relative to control littermates. Osteoblast number and mineral apposition rate were significantly increased in the Col1a1-Menin-Tg mice. Therefore, osteoblast menin plays a key role in bone development, remodeling, and maintenance. PMID:25538250

  14. Systematic Review and Meta-Analysis of Recombinant Human Bone Morphogenetic Protein-2 in Localized Alveolar Ridge and Maxillary Sinus Augmentation.

    PubMed

    Kelly, Mick P; Vaughn, Olushola L Akinshemoyin; Anderson, Paul A

    2016-05-01

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) is approved by the Food and Drug Administration as a viable alternative to bone graft in spinal fusion and maxillary sinus lift. The research questions for meta-analysis were: Is rhBMP-2 an effective bone graft substitute in localized alveolar ridge augmentation and maxillary sinus floor augmentation? What are the potential adverse events? A search of MEDLINE from January 1980 to January 2014 using PubMed, the Cochrane Database of Systematic Reviews and Controlled Trials, CINAHL, and EMBASE was performed. Searches were performed from Medical Subject Headings. The quality of each study included was graded by Review Manager software. The primary outcome variable was bone formation measured as change in bone height on computed tomogram. A systematic review of adverse events also was performed. A random-effects model was chosen. Continuous variables were calculated using the standardized mean difference and 95% confidence intervals (CIs) comparing improvement from baseline of the experimental group with that of the control group. Change in bone height was calculated using logarithmic odds ratio. Test of significance used the Z statistic with a P value of .05. Ten studies met the criteria for systematic review; 8 studies were included in the meta-analysis. Five studies assessed localized alveolar ridge augmentation and resulted in an overall standardized mean difference of 0.56 (CI, 0.20-0.92) in favor of BMP; this result was statistically important. Three studies assessed maxillary sinus floor augmentation and resulted in an overall standardized mean difference of -0.50 (CI, -0.93 to -0.09), which was meaningfully different in favor of the control group. Adverse events were inconsistently reported, ranging from no complications to widespread adverse events. For localized alveolar ridge augmentation, this meta-analysis showed that rhBMP-2 substantially increases bone height. However, rhBMP-2 does not perform as well as the autograft or allograft in maxillary sinus floor augmentation. Long-term clinical success and adverse events need to be reported with more consistency before definitive conclusions can be made. Copyright © 2016 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  15. An effective delivery vehicle of demineralized bone matrix incorporated with engineered collagen-binding human bone morphogenetic protein-2 to accelerate spinal fusion at low dose.

    PubMed

    Zhu, Weiguo; Qiu, Yong; Sheng, Fei; Yuan, Xinxin; Xu, Leilei; Bao, Hongda; Dai, Jianwu; Zhu, Zezhang

    2017-12-01

    The aim of this study was to investigate the feasibility and efficacy of a new delivery matrix using demineralized bone matrix (DBM) incorporated with collagen-binding bone morphogenetic protein-2 (CBD-BMP-2) in the rat inter-transverse spinal fusion model. Sixty rats undergoing posterolateral (inter-transverse) spinal fusion were divided into 3 groups according to the fusion materials containing different components (n = 20 per group). Group A were implanted with DBM, Group B with combination of DBM and BMP-2 and Group C with combination of DBM and CBD-BMP-2. After surgery, the spinal fusion of all the rats was assessed by plain radiography, CT + 3D reconstruction, manual palpation and histological evaluation. Significant difference was found in terms of solid fusion rate among the three groups, with 95% in Group C, 65% in Group B and 0% in Group A (P < 0.001). Compared with Groups B and A, new bone formation was observed earlier and was obvious larger, trabecular bone microarchitecture assessment was better and bone mineral density was statistically larger in Group C. In addition, more newly woven bone and osteocytes were shown by histological evaluation in Group C at 4 weeks post-operation. The present study showed CBD domain could help BMP-2 to improve the efficiency of posterolateral spinal fusion. DBM scaffold activated by collagen-binding BMP-2 was a feasible and promising bone repair vehicle. The present study showed better results in terms of plain radiography, CT + 3D reconstruction, manual palpation and histological evaluation in the rat inter-transverse spinal fusion model using DBM+CBD-BMP-2, compared with DBM+BMP-2 and DBM alone, indicating DBM scaffold activated by collagen-binding BMP-2 was a feasible and promising bone repair vehicle.

  16. Sequential VEGF and BMP-2 releasing PLA-PEG-PLA scaffolds for bone tissue engineering: I. Design and in vitro tests.

    PubMed

    Eğri, Sinan; Eczacıoğlu, Numan

    2017-03-01

    Biodegradable PLA-PEG-PLA block copolymers were synthesized with desired backbone structures and molecular weights using PEG20000. Rectangular scaffolds were prepared by freeze drying with or without using NaCl particles. Bone morphogenetic protein (BMP)-2 was loaded to the matrix after the scaffold formation for sustained release while vascular endothelial growth factor (VEGF) was loaded within the pores with gelatin solution. VEGF release was quite fast and almost 60% of it was released in 2 d. However, sequential - sustained released was observed for BMP-2 in the following few months. Corporation of VEGF/BMP-2 couple into the scaffolds increased the cell adhesion and proliferation. Neither significant cytotoxicity nor apoptosis/necrosis were observed.

  17. Immunohistochemical localization of bone morphogenetic proteins and the receptors in epiphyseal growth plate.

    PubMed

    Yazaki, Y; Matsunaga, S; Onishi, T; Nagamine, T; Origuchi, N; Yamamoto, T; Ishidou, Y; Imamura, T; Sakou, T

    1998-01-01

    The expression of bone morphogenetic proteins (BMPs) and BMP receptors (BMPRs) in the epiphyseal growth plate has not been clarified. In this study, we studied immunohistochemically the spatial and temporal localization of BMP-2/4, osteogenic protein-1 (OP-1, or BMP-7), and BMP receptors (BMPR-IA, BMPR-IB, and BMPR-II) in the epiphyseal plate of growing rats. The proximal parts of tibia in growing rats were observed. At 12 weeks after birth, BMP-2/4 and OP-1 were expressed markedly in proliferating and maturing chondrocytes. BMPR-IA, IB and II were clearly co-expressed in proliferating and maturing chondrocytes, and the expression was decreased in hypertrophic chondrocytes. At 24 weeks, the expression of BMP-2/4 and OP-1 was decreased, but BMPRs were still well-expressed in proliferating chondrocytes. The temporal and spatial expression of BMP and BMPR suggests that BMP and BMP receptors play roles in the multistep cascade of enchondral ossification in the epiphyseal growth plate.

  18. Repulsive Guidance Molecule is a structural bridge between Neogenin and Bone Morphogenetic Protein

    PubMed Central

    Healey, Eleanor G.; Bishop, Benjamin; Elegheert, Jonathan; Bell, Christian H.; Padilla-Parra, Sergi; Siebold, Christian

    2015-01-01

    Repulsive guidance molecules (RGMs) control crucial processes spanning cell motility, adhesion, immune cell regulation and systemic iron metabolism. RGMs signal via two fundamental signaling cascades: the Neogenin (NEO1) and the Bone Morphogenetic Protein (BMP) pathways. Here, we report crystal structures of the N-terminal domains of all human RGM family members in complex with the BMP ligand BMP2, revealing a novel protein fold and a conserved BMP-binding mode. Our structural and functional data suggest a pH-linked mechanism for RGM-activated BMP signaling and offer a rationale for RGM mutations causing juvenile hemochromatosis. We also determined the ternary BMP2–RGM–NEO1 complex crystal structure, which combined with solution scattering and live-cell super-resolution fluorescence microscopy, indicates BMP-induced clustering of the RGM–NEO1 complex. Our results show how RGM acts as the central hub linking BMP and NEO1 and physically connecting these fundamental signaling pathways. PMID:25938661

  19. Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Montesano, Roberto; Sarkoezi, Rita; Schramek, Herbert

    2008-09-12

    Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hithertomore » unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.« less

  20. ECSIT links TLR and BMP signaling in FOP connective tissue progenitor cells.

    PubMed

    Wang, Haitao; Behrens, Edward M; Pignolo, Robert J; Kaplan, Frederick S

    2018-04-01

    Clinical and laboratory observations strongly suggest that the innate immune system induces flare-ups in the setting of dysregulated bone morphogenetic protein (BMP) signaling in fibrodysplasia ossificans progressiva (FOP). In order to investigate the signaling substrates of this hypothesis, we examined toll-like receptor (TLR) activation and bone morphogenetic protein (BMP) signaling in connective tissue progenitor cells (CTPCs) from FOP patients and unaffected individuals. We found that inflammatory stimuli broadly activate TLR expression in FOP CTPCs and that TLR3/TLR4 signaling amplifies BMP pathway signaling through both ligand dependent and independent mechanisms. Importantly, Evolutionarily Conserved Signaling Intermediate in the Toll Pathway (ECSIT) integrates TLR injury signaling with dysregulated BMP pathway signaling in FOP CTPCs. These findings provide novel insight into the cell autonomous integration of injury signals from the innate immune system with dysregulated response signals from the BMP signaling pathway and provide new exploratory targets for therapeutic approaches to blocking the induction and amplification of FOP lesions. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. Balancing the Rates of New Bone Formation and Polymer Degradation Enhances Healing of Weight-Bearing Allograft/Polyurethane Composites in Rabbit Femoral Defects

    PubMed Central

    Dumas, Jerald E.; Prieto, Edna M.; Zienkiewicz, Katarzyna J.; Guda, Teja; Wenke, Joseph C.; Bible, Jesse; Holt, Ginger E.

    2014-01-01

    There is a compelling clinical need for bone grafts with initial bone-like mechanical properties that actively remodel for repair of weight-bearing bone defects, such as fractures of the tibial plateau and vertebrae. However, there is a paucity of studies investigating remodeling of weight-bearing bone grafts in preclinical models, and consequently there is limited understanding of the mechanisms by which these grafts remodel in vivo. In this study, we investigated the effects of the rates of new bone formation, matrix resorption, and polymer degradation on healing of settable weight-bearing polyurethane/allograft composites in a rabbit femoral condyle defect model. The grafts induced progressive healing in vivo, as evidenced by an increase in new bone formation, as well as a decrease in residual allograft and polymer from 6 to 12 weeks. However, the mismatch between the rates of autocatalytic polymer degradation and zero-order (independent of time) new bone formation resulted in incomplete healing in the interior of the composite. Augmentation of the grafts with recombinant human bone morphogenetic protein-2 not only increased the rate of new bone formation, but also altered the degradation mechanism of the polymer to approximate a zero-order process. The consequent matching of the rates of new bone formation and polymer degradation resulted in more extensive healing at later time points in all regions of the graft. These observations underscore the importance of balancing the rates of new bone formation and degradation to promote healing of settable weight-bearing bone grafts that maintain bone-like strength, while actively remodeling. PMID:23941405

  2. Bone matrix to growth factors: location, location, location

    PubMed Central

    Todorovic, Vesna

    2010-01-01

    The demonstration that fibrillin-1 mutations perturb transforming growth factor (TGF)–β bioavailability/signaling in Marfan syndrome (MFS) changed the view of the extracellular matrix as a passive structural support to a dynamic modulator of cell behavior. In this issue, Nistala et al. (2010. J. Cell Biol. doi: 10.1083/jcb.201003089) advance this concept by demonstrating how fibrillin-1 and -2 regulate TGF-β and bone morphogenetic protein (BMP) action during osteoblast maturation. PMID:20855500

  3. Facilitated receptor-recognition and enhanced bioactivity of bone morphogenetic protein-2 on magnesium-substituted hydroxyapatite surface

    PubMed Central

    Huang, Baolin; Yuan, Yuan; Li, Tong; Ding, Sai; Zhang, Wenjing; Gu, Yuantong; Liu, Changsheng

    2016-01-01

    Biomaterial surface functionalized with bone morphogenetic protein-2 (BMP-2) is a promising approach to fabricating successful orthopedic implants/scaffolds. However, the bioactivity of BMP-2 on material surfaces is still far from satisfactory and the mechanism of related protein-surface interaction remains elusive. Based on the most widely used bone-implants/scaffolds material, hydroxyapatite (HAP), we developed a matrix of magnesium-substituted HAP (Mg-HAP, 2.2 at% substitution) to address these issues. Further, we investigated the adsorption dynamics, BMPRs-recruitment, and bioactivity of recombinant human BMP-2 (rhBMP-2) on the HAP and Mg-HAP surfaces. To elucidate the mechanism, molecular dynamic simulations were performed to calculate the preferred orientations, conformation changes, and cysteine-knot stabilities of adsorbed BMP-2 molecules. The results showed that rhBMP-2 on the Mg-HAP surface exhibited greater bioactivity, evidenced by more facilitated BMPRs-recognition and higher ALP activity than on the HAP surface. Moreover, molecular simulations indicated that BMP-2 favoured distinct side-on orientations on the HAP and Mg-HAP surfaces. Intriguingly, BMP-2 on the Mg-HAP surface largely preserved the active protein structure evidenced by more stable cysteine-knots than on the HAP surface. These findings explicitly clarify the mechanism of BMP-2-HAP/Mg-HAP interactions and highlight the promising application of Mg-HAP/BMP-2 matrixes in bone regeneration implants/scaffolds. PMID:27075233

  4. Facilitated receptor-recognition and enhanced bioactivity of bone morphogenetic protein-2 on magnesium-substituted hydroxyapatite surface

    NASA Astrophysics Data System (ADS)

    Huang, Baolin; Yuan, Yuan; Li, Tong; Ding, Sai; Zhang, Wenjing; Gu, Yuantong; Liu, Changsheng

    2016-04-01

    Biomaterial surface functionalized with bone morphogenetic protein-2 (BMP-2) is a promising approach to fabricating successful orthopedic implants/scaffolds. However, the bioactivity of BMP-2 on material surfaces is still far from satisfactory and the mechanism of related protein-surface interaction remains elusive. Based on the most widely used bone-implants/scaffolds material, hydroxyapatite (HAP), we developed a matrix of magnesium-substituted HAP (Mg-HAP, 2.2 at% substitution) to address these issues. Further, we investigated the adsorption dynamics, BMPRs-recruitment, and bioactivity of recombinant human BMP-2 (rhBMP-2) on the HAP and Mg-HAP surfaces. To elucidate the mechanism, molecular dynamic simulations were performed to calculate the preferred orientations, conformation changes, and cysteine-knot stabilities of adsorbed BMP-2 molecules. The results showed that rhBMP-2 on the Mg-HAP surface exhibited greater bioactivity, evidenced by more facilitated BMPRs-recognition and higher ALP activity than on the HAP surface. Moreover, molecular simulations indicated that BMP-2 favoured distinct side-on orientations on the HAP and Mg-HAP surfaces. Intriguingly, BMP-2 on the Mg-HAP surface largely preserved the active protein structure evidenced by more stable cysteine-knots than on the HAP surface. These findings explicitly clarify the mechanism of BMP-2-HAP/Mg-HAP interactions and highlight the promising application of Mg-HAP/BMP-2 matrixes in bone regeneration implants/scaffolds.

  5. Fabrication of Vascularized Bone Flaps with Sustained Release of Recombinant Human Bone Morphogenetic Protein-2 and Arteriovenous Bundle.

    PubMed

    Li, Bo; Ruan, Changshun; Ma, Yufei; Huang, Zhifeng; Huang, Zhenfei; Zhou, Gang; Zhang, Jing; Wang, Hai; Wu, Zhihong; Qiu, Guixing

    2018-05-21

    It is a common treatment strategy in the clinic to transplant a vascularized bone flap for a large bone defect. But it is difficult for peripheral blood vessels to grow into the central region of a large bone construct. In this study, we fabricated a vascularized bone flap from a three-dimensional (3D)-printed biodegradable poly(lactide-co-glycolide) (PLGA)/β-tri-calcium phosphate (β-TCP) scaffold using the combination of an arteriovenous (AV) bundle and recombinant human bone morphogenetic protein-2 (rhBMP-2). A degradable porous PLGA/β-TCP scaffold was prepared by adopting 3D plotting and a low-temperature deposition technique. rhBMP-2 chitosan microspheres (CMs) were fabricated and loaded into the scaffolds to induce ectopic bone formation. In Group SBV (scaffold+rhBMP-2+vessel), a femoral AV bundle was implanted into the central tunnel of the composite before embedding into intramuscular pockets. In Group SB (scaffold+rhBMP-2), the composite was directly implanted into intramuscular pockets. Bone formation was evaluated by imaging analysis (X-rays and microcomputed tomography) and histological analysis (Hematoxylin and Eosin staining and Masson staining) after 4 and 12 weeks, respectively. Vascularization was also assessed by imaging analysis (Microfil angiography) and histological analysis (CD31 immunohistochemical staining). The 3D-printed PLGA/β-TCP scaffold had good cytocompatibility. Ectopic bone formation in the scaffold could be successfully induced by the controlled release of rhBMP-2 through CMs. Comparing groups SBV and SB, vascularization of the composite was significantly enhanced by AV bundle implantation at 4 and 12 weeks. Moreover, rhBMP-2-induced bone formation was also significantly improved by the AV bundle at 4 and 12 weeks. The AV bundle not only improved vascularization and bone formation of the construct, but also provided a defined vascular axis to connect with the vascular system of the bone defect by microsurgical techniques. It provided a new potential treatment strategy to repair large bone defects, especially for those with low vascular supply.

  6. BMP2-loaded hollow hydroxyapatite microspheres exhibit enhanced osteoinduction and osteogenicity in large bone defects.

    PubMed

    Xiong, Long; Zeng, Jianhua; Yao, Aihua; Tu, Qiquan; Li, Jingtang; Yan, Liang; Tang, Zhiming

    2015-01-01

    The regeneration of large bone defects is an osteoinductive, osteoconductive, and osteogenic process that often requires a bone graft for support. Limitations associated with naturally autogenic or allogenic bone grafts have demonstrated the need for synthetic substitutes. The present study investigates the feasibility of using novel hollow hydroxyapatite microspheres as an osteoconductive matrix and a carrier for controlled local delivery of bone morphogenetic protein 2 (BMP2), a potent osteogenic inducer of bone regeneration. Hollow hydroxyapatite microspheres (100±25 μm) with a core (60±18 μm) and a mesoporous shell (180±42 m(2)/g surface area) were prepared by a glass conversion technique and loaded with recombinant human BMP2 (1 μg/mg). There was a gentle burst release of BMP2 from microspheres into the surrounding phosphate-buffered saline in vitro within the initial 48 hours, and continued at a low rate for over 40 days. In comparison with hollow hydroxyapatite microspheres without BMP2 or soluble BMP2 without a carrier, BMP2-loaded hollow hydroxyapatite microspheres had a significantly enhanced capacity to reconstitute radial bone defects in rabbit, as shown by increased serum alkaline phosphatase; quick and complete new bone formation within 12 weeks; and great biomechanical flexural strength. These results indicate that BMP2-loaded hollow hydroxyapatite microspheres could be a potential new option for bone graft substitutes in bone regeneration.

  7. Collagen Sponge Functionalized with Chimeric Anti-BMP-2 Monoclonal Antibody Mediates Repair of Critical-Size Mandibular Continuity Defects in a Nonhuman Primate Model

    PubMed Central

    Xie, Yilin; Su, Yingying; Tang, Jianxia; Goh, Bee Tin; Saigo, Leonardo; Zhang, Chunmei; Wang, Jinsong; Khojasteh, Arash; Wang, Songlin

    2017-01-01

    Antibody-mediated osseous regeneration (AMOR) has been introduced by our research group as a tissue engineering approach to capture of endogenous growth factors through the application of specific monoclonal antibodies (mAbs) immobilized on a scaffold. Specifically, anti-Bone Morphogenetic Protein- (BMP-) 2 mAbs have been demonstrated to be efficacious in mediating bone repair in a number of bone defects. The present study sought to investigate the application of AMOR for repair of mandibular continuity defect in nonhuman primates. Critical-sized mandibular continuity defects were created in Macaca fascicularis locally implanted with absorbable collagen sponges (ACS) functionalized with chimeric anti-BMP-2 mAb or isotype control mAb. 2D and 3D analysis of cone beam computed tomography (CBCT) imaging demonstrated increased bone density and volume observed within mandibular continuity defects implanted with collagen scaffolds functionalized with anti-BMP-2 mAb, compared with isotype-matched control mAb. Both CBCT imaging and histologic examination demonstrated de novo bone formation that was in direct apposition to the margins of the resected bone. It is hypothesized that bone injury may be necessary for AMOR. This is evidenced by de novo bone formation adjacent to resected bone margins, which may be the source of endogenous BMPs captured by anti-BMP-2 mAb, in turn mediating bone repair. PMID:28401163

  8. Carbon nanotubes with high bone-tissue compatibility and bone-formation acceleration effects.

    PubMed

    Usui, Yuki; Aoki, Kaoru; Narita, Nobuyo; Murakami, Narumichi; Nakamura, Isao; Nakamura, Koichi; Ishigaki, Norio; Yamazaki, Hiroshi; Horiuchi, Hiroshi; Kato, Hiroyuki; Taruta, Seiichi; Kim, Yoong Ahm; Endo, Morinobu; Saito, Naoto

    2008-02-01

    Carbon nanotubes (CNTs) have been used in various fields as composites with other substances or alone to develop highly functional materials. CNTs hold great interest with respect to biomaterials, particularly those to be positioned in contact with bone such as prostheses for arthroplasty, plates or screws for fracture fixation, drug delivery systems, and scaffolding for bone regeneration. Accordingly, bone-tissue compatibility of CNTs and CNT influence on bone formation are important issues, but the effects of CNTs on bone have not been delineated. Here, it is found that multi-walled CNTs adjoining bone induce little local inflammatory reaction, show high bone-tissue compatibility, permit bone repair, become integrated into new bone, and accelerate bone formation stimulated by recombinant human bone morphogenetic protein-2 (rhBMP-2). This study provides an initial investigational basis for CNTs in biomaterials that are used adjacent to bone, including uses to promote bone regeneration. These findings should encourage development of clinical treatment modalities involving CNTs.

  9. Local treatment of cancellous bone grafts with BMP-7 and zoledronate increases both the bone formation rate and bone density

    PubMed Central

    2011-01-01

    Background and purpose The remodeling of morselized bone grafts in revision surgery can be enhanced by an anabolic substance such as a bone morphogenetic protein (BMP). On the other hand, BMPs boost catabolism and might cause a premature resorption, both of the graft and of the new-formed bone. Bisphosphonates inactivate osteoclasts and can be used to control the resorption. We studied a combination of both drugs as a local admix to a cancellous allograft. Methods Cancellous bone allografts were harvested and freeze-dried. Either saline, BMP-7, the bisphosphonate zoledronate, or a combination of BMP-7 and zoledronate were added in solution. The grafts were placed in bone conduction chambers and implanted in the proximal tibia of 34 rats. The grafts were harvested after 6 weeks and evaluated by histomorphometry. Results Bone volume/total volume (BV/TV) was 50% in the grafts treated with the combination of BMP-7 and zoledronate and 16% in the saline controls (p < 0.001). In the zoledronate group BV/TV was 56%, and in the BMP group it was 14%. The ingrowth distance of new bone into the graft was 3.5 mm for the combination of BMP-7 and zoledronate and 2.6 mm in the saline control (p = 0.002). The net amount of retained remodeled bone was more than 4 times higher when BMP-7 and zoledronate were combined than in the controls. Interpretation An anabolic drug like BMP-7 can be combined with an anti-catabolic bisphosphonate as local bone graft adjunct, and the combination increases the amount of remaining bone after remodeling is complete. PMID:21434769

  10. The Effects of rhBMP-2 Released from Biodegradable Polyurethane/Microsphere Composite Scaffolds on New Bone Formation in Rat Femora

    DTIC Science & Technology

    2009-09-17

    bone morphogenetic protein ) Bone regeneration Drug delivery In vivo test Polyurethane a b s t r a c t Scaffolds prepared from biodegradable...Toshitaka Yoshii b, c ,2, Andrea E. Hafeman a,b,3, Jeffry S. Nyman b, c ,d,4, Joseph C . Wenke e,5, Scott A. Guelcher a,b,* aDepartment of Chemical and...Houston, TX, USA a r t i c l e i n f o Article history: Received 18 June 2009 Accepted 26 August 2009 Available online 17 September 2009 Keywords: BMP

  11. Trends of Posterior Long Segment Fusion with and without Recombinant Human Bone Morphogenetic Protein 2 in Patients with Scoliosis.

    PubMed

    Ruofeng, Yin; Cohen, Jeremiah R; Buser, Zorica; Yoon, S Tim; Meisel, Hans-Joerg; Youssef, Jim A; Park, Jong-Beom; Wang, Jeffrey C; Brodke, Darrel S

    2016-08-01

    Retrospective study. Symptomatic scoliosis can be a source of severe pain and disability. When nonoperative treatments fail, spine fusion is considered as an effective procedure in scoliosis management. The purpose of this study was to evaluate the trends of patients with scoliosis undergoing posterior long segment fusion (PLSF) with and without recombinant human bone morphogenetic protein 2 (rhBMP-2). Patients within the orthopedic subset of Medicare database undergoing PLSF from 2005 to 2011 were identified using the PearlDiver Patient Records Database. Both diagnosis and procedural International Classification of Diseases, ninth edition and Current Procedural Terminology codes were used. The year of procedure, age, sex, region, and rhBMP-2 use were recorded. In total, 1,265,591 patients with scoliosis were identified with 29,787 PLSF surgeries between 2005 and 2011. The incidence of PLSF procedures increased gradually from 2005 to 2009, decreased in 2010 (p < 0 0.01), and grew again in 2011. Patients over age 84 years had the highest incidence of PLSF. The lowest incidence of the procedures was in the Northeast, 5.96 per 100,000 patients. Sex differences were observed with a male-to-female ratio of 0.40 (p < 0.01). The use of rhBMP-2 for PLSF increased steadily from 2005 to 2009; the numbers dropped dramatically in 2010 and returned by 2011. According to our study, patients with scoliosis demonstrated a 0.6575 average incidence increase of PLSF treatments annually. There were significant differences in incidence of PLSF procedure and patient demographics. Additionally, rhBMP-2 consumption significantly changed when we stratified it by sex, age, and region respectively.

  12. Trends and Cost of Posterior Cervical Fusions With and Without Recombinant Human Bone Morphogenetic Protein-2 in the US Medicare Population.

    PubMed

    Myhre, Sue Lynn; Buser, Zorica; Meisel, Hans-Joerg; Brodke, Darrel S; Yoon, S Tim; Wang, Jeffrey C; Park, Jong-Beom; Youssef, Jim A

    2017-06-01

    Retrospective database review. To analyze and report the trends and cost of posterior cervical fusions (PCFs) with and without off-label recombinant human bone morphogenetic protein-2 (rhBMP-2) in the Medicare population. Patient records from the PearlDiver database were retrospectively reviewed from January 1, 2005, to December 31, 2012, to distinguish individuals who underwent a PCF with or without rhBMP-2. Total numbers, incidence, age, gender, geographic region, reimbursement, and length of stay were analyzed and summarized. The combined total of non-rhBMP-2 (n = 39 479; 85.51%) and rhBMP-2 PCF (n = 6692; 14.49%) procedures performed between 2005 and 2012 was 46 171. In general, the number of PCFs without rhBMP-2 consistently increased over time, while the number of PCFs with rhBMP-2 had only a slight increase from 2005 to 2012. On average, PCFs without rhBMP-2 were associated with $1197 higher cost than those with rhBMP-2, but the average length of stay was similar (6 days). From 2005 to 2012, the average cost for procedures with and without rhBMP-2 increased by $12 605 and $7291, respectively. The percentage of rhBMP-2 use peaked in 2007 and dwindled until 2010, and declined an additional 2.84% from 2011 to 2012. Multiple age, region, and gender tendencies were observed. To our knowledge, this was the first study to use the PearlDiver database to report incidence and cost trends of PCF procedures. This article provides meaningful trend data on PCFs to surgeons and clinicians, researchers, and patients, as well as functions as a beacon for future research questions.

  13. Synergistic effects of fibronectin and bone morphogenetic protein on the bioactivity of titanium metal.

    PubMed

    Biao, M N; Chen, Y M; Xiong, S B; Wu, B Y; Yang, B C

    2017-09-01

    To improve the biological properties of bioactive titanium metal, recombinant human bone morphogenetic protein 2(rhBMP-2) and fibronectin (Fn) were adsorbed on its surface solely or contiguously to modify the anodic oxidized titanium (AO-Ti), acid-alkali-treated titanium (AA-Ti), and polished titanium (P-Ti). It is found that the different bioactive titanium surface structures had great influence on protein adsorption. The adsorption amounts of BMP adsorbed solely and Fn/BMP adsorbed contiguously were AA-Ti > P-Ti > AO-Ti, and that for Fn adsorbed solely was AA-Ti ≈ P-Ti > AO-Ti. The conformation of proteins was changed remarkably after the adsorption. For BMP, the α-helix decreased on AA-Ti and stabilized on P-Ti and AO-Ti. For Fn, the β-sheet on PT-Ti and AA-Ti increased significantly. For Fn/BMP, the percentage of β-sheet on AA-Ti increased, and that of α-helix on all samples was stable. MSCs showed greater adhesion and spreading on Fn/BMP groups. MTT and Elisa tests showed that the synergistic effects of proteins made the cells proliferate and differentiate faster. It indicated both the surface structure and the synergistic effects of proteins could influence the biological properties of titanium metals. It provides research foundation for improving the biological properties of bioactive titanium metals by simultaneous application of several proteins. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2485-2498, 2017. © 2017 Wiley Periodicals, Inc.

  14. Crestal Sinus Augmentation with Recombinant Human Bone Morphogenetic Protein 2: Clinical and Radiographic Outcomes of 2-Year Pilot Trial.

    PubMed

    Kuchler, Ulrike; Rudelstorfer, Claudia M; Barth, Barbara; Tepper, Gabor; Lidinsky, Dominika; Heimel, Patrick; Watzek, Georg; Gruber, Reinhard

    Recombinant human bone morphogenetic protein 2 (rhBMP-2) together with an absorbable collagen carrier (ACS) was approved for augmentation of the maxillary sinus prior to implant placement. The original registration trial was based on a lateral window approach. Clinical outcomes of crestal sinus augmentation with rhBMP-2 have not been reported so far. An uncontrolled pilot trial in which seven patients with a residual maxillary height below 5 mm were enrolled to receive crestal sinus augmentation with rhBMP-2/ACS was conducted. Elevation of the sinus mucosa was performed by gel pressure. Primary endpoints were the gain in augmentation height and volume measured by computed tomography after 6 months. Evaluation of bone quality at the time of implant placement was based on histology. Secondary endpoints were the clinical and radiologic evaluation of the implants and patient satisfaction by visual analog scale (VAS) at the 2-year follow-up. Median gain in augmentation height was 7.2 mm (range 0.0 to 17.5 mm). Five patients gained at least 5 mm of bone height. Two patients with a perforation of the sinus mucosa failed to respond to rhBMP-2/ACS and underwent lateral window augmentation. The median gain in augmentation volume of the five patients was 781.3 mm³ (range 426.9 to 1,242.8 mm³). Biopsy specimens showed a cancellous network consisting of primary plexiform bone with little secondary lamellar bone. After 2 years, implants were in function with no signs of inflammation or peri-implant bone loss. Patients were satisfied with the esthetic outcomes and chewing function. This pilot clinical trial supports the original concept that rhBMP-2/ACS supports bone formation, also in crestal sinus augmentation, and emphasizes the relevance of the integrity of the sinus mucosa to predict the bone gain.

  15. Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

    NASA Astrophysics Data System (ADS)

    Mikulska, Anna; Filipowska, Joanna; Osyczka, Anna; Nowakowska, Maria; Szczubiałka, Krzysztof

    2014-12-01

    Polymeric surfaces suitable for cell culture (DR/Pec) were constructed from diazoresin (DR) and pectin (Pec) in a form of ultrathin films using the layer-by-layer (LbL) technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs) to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins) was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP) activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2) to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2

  16. Selective Small Molecule Compounds Increase BMP-2 Responsiveness by Inhibiting Smurf1-mediated Smad1/5 Degradation

    PubMed Central

    Cao, Yu; Wang, Cheng; Zhang, Xueli; Xing, Guichun; Lu, Kefeng; Gu, Yongqing; He, Fuchu; Zhang, Lingqiang

    2014-01-01

    The ubiquitin ligase Smad ubiquitination regulatory factor-1 (Smurf1) negatively regulates bone morphogenetic protein (BMP) pathway by ubiquitinating certain signal components for degradation. Thus, it can be an eligible pharmacological target for increasing BMP signal responsiveness. We established a strategy to discover small molecule compounds that block the WW1 domain of Smurf1 from interacting with Smad1/5 by structure based virtual screening, molecular experimental examination and cytological efficacy evaluation. Our selected hits could reserve the protein level of Smad1/5 from degradation by interrupting Smurf1-Smad1/5 interaction and inhibiting Smurf1 mediated ubiquitination of Smad1/5. Further, these compounds increased BMP-2 signal responsiveness and the expression of certain downstream genes, enhanced the osteoblastic activity of myoblasts and osteoblasts. Our work indicates targeting Smurf1 for inhibition could be an accessible strategy to discover BMP-sensitizers that might be applied in future clinical treatments of bone disorders such as osteopenia. PMID:24828823

  17. Elevated extracellular calcium increases expression of bone morphogenetic protein-2 gene via a calcium channel and ERK pathway in human dental pulp cells

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tada, Hiroyuki; Nemoto, Eiji, E-mail: e-nemoto@umin.ac.jp; Kanaya, Sousuke

    Dental pulp cells, which have been shown to share phenotypical features with osteoblasts, are capable of differentiating into odontoblast-like cells and generating a dentin-like mineral structure. Elevated extracellular Ca{sup 2+}Ca{sub o}{sup 2+} has been implicated in osteogenesis by stimulating the proliferation and differentiation of osteoblasts; however, the role of Ca{sub o}{sup 2+} signaling in odontogenesis remains unclear. We found that elevated Ca{sub o}{sup 2+} increases bone morphogenetic protein (BMP)-2 gene expression in human dental pulp cells. The increase was modulated not only at a transcriptional level but also at a post-transcriptional level, because treatment with Ca{sup 2+} increased the stabilitymore » of BMP-2 mRNA in the presence of actinomycin D, an inhibitor of transcription. A similar increase in BMP-2 mRNA level was observed in other human mesenchymal cells from oral tissue; periodontal ligament cells and gingival fibroblasts. However, the latter cells exhibited considerably lower expression of BMP-2 mRNA compared with dental pulp cells and periodontal ligament cells. The BMP-2 increase was markedly inhibited by pretreatment with an extracellular signal-regulated kinase (ERK) inhibitor, PD98059, and partially inhibited by the L-type Ca{sup 2+} channels inhibitor, nifedipine. However, pretreatment with nifedipine had no effect on ERK1/2 phosphorylation triggered by Ca{sup 2+}, suggesting that the Ca{sup 2+} influx from Ca{sup 2+} channels may operate independently of ERK signaling. Dental pulp cells do not express the transcript of Ca{sup 2+}-sensing receptors (CaSR) and only respond slightly to other cations such as Sr{sup 2+} and spermine, suggesting that dental pulp cells respond to Ca{sub o}{sup 2+} to increase BMP-2 mRNA expression in a manner different from CaSR and rather specific for Ca{sub o}{sup 2+} among cations.« less

  18. Periodontal ligament stem/progenitor cells with protein-releasing scaffolds for cementum formation and integration on dentin surface.

    PubMed

    Cho, Hankyu; Tarafder, Solaiman; Fogge, Michael; Kao, Kristy; Lee, Chang H

    2016-11-01

    Purpose/Aim: Cementogenesis is a critical step in periodontal tissue regeneration given the essential role of cementum in anchoring teeth to the alveolar bone. This study is designed to achieve integrated cementum formation on the root surfaces of human teeth using growth factor-releasing scaffolds with periodontal ligament stem/progenitor cells (PDLSCs). Human PDLSCs were sorted by CD146 expression, and characterized using CFU-F assay and induced multi-lineage differentiation. Polycaprolactone scaffolds were fabricated using 3D printing, embedded with poly(lactic-co-glycolic acids) (PLGA) microspheres encapsulating connective tissue growth factor (CTGF), bone morphogenetic protein-2 (BMP-2), or bone morphogenetic protein-7 (BMP-7). After removing cementum on human tooth roots, PDLSC-seeded scaffolds were placed on the exposed dentin surface. After 6-week culture with cementogenic/osteogenic medium, cementum formation and integration were evaluated by histomorphometric analysis, immunofluorescence, and qRT-PCR. Periodontal ligament (PDL) cells sorted by CD146 and single-cell clones show a superior clonogenecity and multipotency as compared with heterogeneous populations. After 6 weeks, all the growth factor-delivered groups showed resurfacing of dentin with a newly formed cementum-like layer as compared with control. BMP-2 and BMP-7 showed de novo formation of tissue layers significantly thicker than all the other groups, whereas CTGF and BMP-7 resulted in significantly improved integration on the dentin surface. The de novo mineralized tissue layer seen in BMP-7-treated samples expressed cementum matrix protein 1 (CEMP1). Consistently, BMP-7 showed a significant increase in CEMP1 mRNA expression. Our findings represent important progress in stem cell-based cementum regeneration as an essential part of periodontium regeneration.

  19. Emulating Native Periosteum Cell Population and Subsequent Paracrine Factor Production To Promote Tissue Engineered Periosteum-Mediated Allograft Healing

    PubMed Central

    Hoffman, Michael D.

    2015-01-01

    Emulating autograft healing within the context of decellularized bone allografts has immediate clinical applications in the treatment of critical-sized bone defects. The periosteum, a thin, osteogenic tissue that surrounds bone, houses a heterogeneous population of stem cells and osteoprogenitors. There is evidence that periosteum-cell derived paracrine factors, specifically vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2), orchestrate autograft healing through host cell recruitment and subsequent tissue elaboration. In previous work, we demonstrated that the use of poly(ethylene glycol) (PEG) hydrogels as a tissue engineered (T.E.) periosteum to localize mesenchymal stem cells (MSCs) to the surface of decellularized bone enhances allograft healing and integration. Herein, we utilize a mixed population of 50:50 MSCs and osteoprogenitor cells to better mimic native periosteum cell population and paracrine factor production to further promote allograft healing. This mixed cell population was localized to the surface of decellularized allografts within degradable hydrogels and shown to expedite allograft healing. Specifically, bone callus formation and biomechanical graft-host integration are increased as compared to unmodified allografts. These results demonstrate the dual importance of periosteum-mediated paracrine factors orchestrating host cell recruitment as well as new bone formation while developing clinically translatable strategies for allograft healing and integration. PMID:25818449

  20. The effect of levetiracetam on rat bone mass, structure and metabolism.

    PubMed

    Fekete, Sona; Simko, Julius; Gradosova, Iveta; Malakova, Jana; Zivna, Helena; Palicka, Vladimir; Zivny, Pavel

    2013-11-01

    To determine the effect of levetiracetam (LEV) Lon bone mineral density (BMD), mineral content (BMC), bone markers, body composition and bone mechanical strength in the orchidectomised (ORX) rat model. 16 orchidectomised Wistar rats were divided into control and test groups, 8 rats in each group. The control rats received standard laboratory diet (SLD) while rats in the test group were fed with SLD enriched with LEV for 12 weeks. BMD was measured by dual energy X-ray absorptiometry at the whole body, lumbar spine and femur. Bone marker concentrations were examined of osteoprotegerin (OPG) and insulin-like growth factor 1 (IGF-1) in serum, and amino-terminal propeptide of procollagen type I (PINP), carboxy-terminal cross-linking telopeptide of type I collagen (CTX-I), bone alkaline phosphatase (ALPL), and bone morphogenetic protein 2 (BMP-2) in bone homogenate. The femurs were used for biomechanical testing. Compared to the control group we found lower fat mass, lower BMD in the area of the left femur, lower BMC in both femurs, a reduced concentration of OPG, and an increased concentration of CTX-I of borderline statistical significance (p=0.0661). Biomechanical parameters did not differ between groups. Significant loss of BMD or BMC was seen at the left and right femur area in the LEV group. Administration of LEV in the ORX-rat model significantly decreased levels of OPG (marker of bone formation) in serum and increased levels of CTX-I (marker of bone resorption) in bone homogenate, but results in this study did not reveal any change in biomechanical bone strength. Administration of LEV in the ORX-rat model may reduce adipose tissue. Further studies in animals and humans will be needed to confirm these findings. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Isometric Scaling in Developing Long Bones Is Achieved by an Optimal Epiphyseal Growth Balance

    PubMed Central

    Stern, Tomer; Aviram, Rona; Rot, Chagai; Galili, Tal; Sharir, Amnon; Kalish Achrai, Noga; Keller, Yosi; Shahar, Ron; Zelzer, Elazar

    2015-01-01

    One of the major challenges that developing organs face is scaling, that is, the adjustment of physical proportions during the massive increase in size. Although organ scaling is fundamental for development and function, little is known about the mechanisms that regulate it. Bone superstructures are projections that typically serve for tendon and ligament insertion or articulation and, therefore, their position along the bone is crucial for musculoskeletal functionality. As bones are rigid structures that elongate only from their ends, it is unclear how superstructure positions are regulated during growth to end up in the right locations. Here, we document the process of longitudinal scaling in developing mouse long bones and uncover the mechanism that regulates it. To that end, we performed a computational analysis of hundreds of three-dimensional micro-CT images, using a newly developed method for recovering the morphogenetic sequence of developing bones. Strikingly, analysis revealed that the relative position of all superstructures along the bone is highly preserved during more than a 5-fold increase in length, indicating isometric scaling. It has been suggested that during development, bone superstructures are continuously reconstructed and relocated along the shaft, a process known as drift. Surprisingly, our results showed that most superstructures did not drift at all. Instead, we identified a novel mechanism for bone scaling, whereby each bone exhibits a specific and unique balance between proximal and distal growth rates, which accurately maintains the relative position of its superstructures. Moreover, we show mathematically that this mechanism minimizes the cumulative drift of all superstructures, thereby optimizing the scaling process. Our study reveals a general mechanism for the scaling of developing bones. More broadly, these findings suggest an evolutionary mechanism that facilitates variability in bone morphology by controlling the activity of individual epiphyseal plates. PMID:26241802

  2. Low-intensity pulsed ultrasound stimulation facilitates in vitro osteogenic differentiation of human adipose-derived stem cells via up-regulation of heat shock protein (HSP)70, HSP90, and bone morphogenetic protein (BMP) signaling pathway.

    PubMed

    Zhang, Zhonglei; Ma, Yalin; Guo, Shaowen; He, Yi; Bai, Gang; Zhang, Wenjun

    2018-05-29

    Low-intensity pulsed ultrasound (LIPUS) has positive effects on osteogenic differentiation. However, the effect of LIPUS on osteogenic differentiation of human adipose-derived stem cells (hASCs) is unclear. In the present study, we investigated whether LIPUS could promote the proliferation and osteogenic differentiation of hASCs. hASCs were isolated and osteogenically induced with LIPUS stimulation at 20 and 30 mW cm -2 for 30 min day -1 Cell proliferation and osteogenic differentiation potential of hASCs were respectively analyzed by cell counting kit-8 assay, Alizarin Red S staining, real-time polymerase chain reaction, and Western blotting. The results indicated that LIPUS stimulation did not significantly affect the proliferation of hASCs, but significantly increased their alkaline phosphatase activity on day 6 of culture and markedly promoted the formation of mineralized nodules on day 21 of culture. The mRNA expression levels of runt-related transcription factor, osteopontin, and osteocalcin were significantly up-regulated by LIPUS stimulation. LIPUS stimulation did not affect the expression of heat shock protein (HSP) 27, HSP40, bone morphogenetic protein (BMP)-6 and BMP-9, but significantly up-regulated the protein levels of HSP70, HSP90, BMP-2, and BMP-7 in the hASCs. Further studies found that LIPUS increased the mRNA levels of Smad 1 and Smad 5, elevated the phosphorylation of Smad 1/5, and suppressed the expression of BMP antagonist Noggin. These findings indicated that LIPUS stimulation enhanced osteogenic differentiation of hASCs possibly through the up-regulation of HSP70 and HSP90 expression and activation of BMP signaling pathway. Therefore, LIPUS might have the potential to promote the repair of bone defect. © 2018 The Author(s).

  3. Bone Morphogenetic Proteins, Antagonists and Receptors in Prostate Cancer

    DTIC Science & Technology

    2005-01-01

    expressed in prostate. This work investigates BMP receptors and BMP antagonists to understand the basic mechanisms to inhibit the BMP signaling in...during embryoge- nesis, and prostate cancer metastases to bone. BMP functions can be inhibited by antagonists such as Noggin or DAN. DAN is a protein...protein along with a constant 0-6 -1 10 100 1000 1O0ng/ml of BMP-6, we were able to show a ng/ml BMP-6 dose-dependent inhibition of BMP-6 activity in DU

  4. Interaction between bone marrow stromal cells and neuroblastoma cells leads to a VEGFA-mediated osteoblastogenesis.

    PubMed

    HaDuong, Josephine H; Blavier, Laurence; Baniwal, Sanjeev K; Frenkel, Baruch; Malvar, Jemily; Punj, Vasu; Sposto, Richard; DeClerck, Yves A

    2015-08-15

    The potential role of osteoblasts in bone and bone marrow (BM) metastases in neuroblastoma (NBL) remains unclear. In this study, we examined the effect of NBL cells on the osteoblastic differentiation of BM-derived mesenchymal stromal cells (BMMSC). We show that the presence of NBL cells enhanced the osteoblastic differentiation of BMMSC driven by bone morphogenetic protein (BMP)-4, in the absence of any effect on NBL cell proliferation. Expression profiles of BMMSC driven toward osteoblastic differentiation revealed an increase in vascular endothelial growth factor A (Vegfa) expression in the presence of NBL cells. We demonstrated that NBL cells increased BMMSC-derived VEGFA mRNA and protein and that this was enhanced by BMP-4. However, in similar conditions, neither the addition of an mVEGFA blocking antibody nor exogenous recombinant (r) mVEGFA affected osteoblastic differentiation. In contrast, siRNA- mediated knock-down of VEGFA in BMMSC prevented osteoblastic differentiation in BMP-4-treated cocultures, an effect that was not reversed in the presence of rmVEGFA. An analysis of murine bones injected with hNBL cells revealed an increase of mVEGFA producing cells near tumor cells concomitantly with an increase in Vegfa and Runx2 mRNA. This coincided with an increase in osteoclasts, in Rankl/Opg mRNA ratio and with the formation of osteolytic lesions. Thus NBL cells promote osteoblastogenesis in the BM by increasing VEGFA expression in BMMSC. Our study provides a new insight into the role of VEGFA in NBL metastases by pointing to the role of stroma-derived intracrine VEGFA in osteoblastogenesis. © 2015 UICC.

  5. Weak bones in diabetes mellitus - an update on pharmaceutical treatment options.

    PubMed

    Lin, Daphne P L; Dass, Crispin R

    2018-01-01

    Diabetes mellitus is often associated with a number of complications such as nephropathy, neuropathy, retinopathy and foot ulcers. However, weak bone is a diabetic complication that is often overlooked. Although the exact mechanism for weak bones within diabetes mellitus is unclear, studies have shown that the mechanism does differ in both type I (T1DM) and type II diabetes (T2DM). This review, however, investigates the application of mesenchymal stem cells, recombinant human bone morphogenetic protein-2, teriparatide, insulin administration and the effectiveness of a peroxisome proliferator-activated receptor-ϒ modulator, netoglitazone in the context of diabetic weak bones. In T1DM, weak bones may be the result of defective osteoblast activity, the absence of insulin's anabolic effects on bone, the deregulation of the bone-pancreas negative feedback loop and advanced glycation end product (AGE) aggregation within the bone matrix as a result of hyperglycaemia. Interestingly, T2DM patients placed on insulin administration, thiazolidinediones, SGLT2 inhibitors and sulfonylureas have an associated increased fracture risk. T2DM patients are also observed to have high sclerostin levels that impair osteoblast gene transcription, AGE aggregation within bone, which compromises bone strength and a decrease in esRAGE concentration resulting in a negative association with vertebral fractures. Effective treatment options for weak bones in the context of diabetes are currently lacking. There is certainly scope for discovery and development of novel agents that could alleviate this complication in diabetes patients. © 2017 Royal Pharmaceutical Society.

  6. Advancing osteochondral tissue engineering: bone morphogenetic protein, transforming growth factor, and fibroblast growth factor signaling drive ordered differentiation of periosteal cells resulting in stable cartilage and bone formation in vivo.

    PubMed

    Mendes, L F; Katagiri, H; Tam, W L; Chai, Y C; Geris, L; Roberts, S J; Luyten, F P

    2018-02-21

    Chondrogenic mesenchymal stem cells (MSCs) have not yet been used to address the clinical demands of large osteochondral joint surface defects. In this study, self-assembling tissue intermediates (TIs) derived from human periosteum-derived stem/progenitor cells (hPDCs) were generated and validated for stable cartilage formation in vivo using two different animal models. hPDCs were aggregated and cultured in the presence of a novel growth factor (GF) cocktail comprising of transforming growth factor (TGF)-β1, bone morphogenetic protein (BMP)2, growth differentiation factor (GDF)5, BMP6, and fibroblast growth factor (FGF)2. Quantitative polymerase chain reaction (PCR) and immunohistochemistry were used to study in vitro differentiation. Aggregates were then implanted ectopically in nude mice and orthotopically in critical-size osteochondral defects in nude rats and evaluated by microcomputed tomography (µCT) and immunohistochemistry. Gene expression analysis after 28 days of in vitro culture revealed the expression of early and late chondrogenic markers and a significant upregulation of NOGGIN as compared to human articular chondrocytes (hACs). Histological examination revealed a bilayered structure comprising of chondrocytes at different stages of maturity. Ectopically, TIs generated both bone and mineralized cartilage at 8 weeks after implantation. Osteochondral defects treated with TIs displayed glycosaminoglycan (GAG) production, type-II collagen, and lubricin expression. Immunostaining for human nuclei protein suggested that hPDCs contributed to both subchondral bone and articular cartilage repair. Our data indicate that in vitro derived osteochondral-like tissues can be generated from hPDCs, which are capable of producing bone and cartilage ectopically and behave orthotopically as osteochondral units.

  7. The evaluation of lyophilized polymer matrices for administering recombinant human bone morphogenetic protein-2.

    PubMed

    Duggirala, S S; Rodgers, J B; DeLuca, P P

    1996-07-01

    Novel unitary devices, prepared by lyophilization of viscous solutions of sodium carboxymethylcellulose (CMC) and methylcellulose (MC), were evaluated as sustained-release delivery systems for recombinant human bone morphogenetic protein-2 (rhBMP-2). In vitro characterization of the unitary devices, which contained rhBMP-2-loaded poly (d,l lactide-co-glycolide) (PLGA) bioerodible particles (BEPs), was conducted over a 2-month period. Determinations included buffer uptake, mass and molecular weight loss and rhBMP-2 release from the unitary devices. CMC devices imbibed approximately 16 times their weight of buffer, while with MC, equilibrium uptake was approximately 6 times the dry weight of the devices. Overall mass loss percentages were approximately 55 and 35%, respectively, for CMC and MC devices. rhBMP-2 release from the devices was essentially a triphasic process: an initial phase during which "free" protein (rhBMP-2 present on the surface and within the pores of the PLGA BEPs) was released, a lag period during which no release was discerned, and then release of "bound" rhBMP-2 (protein adsorbed to the BEPs). The release of bound protein correlated with the mass loss of the polymer which began after 3 weeks. Release from the unitary devices was lower than that from the BEPs alone, due to a retardation effect of the gelled CMC/MC polymers. In rabbits in which full-thickness cranial bone defects were created, the implants were well tolerated and induced significant new bone growth during an 8-week evaluation period. The CMC devices appear to have induced bone earlier (at 2 weeks), but this did not affect eventual 8-week results. CMC devices without rhBMP-2 appeared to provide some bone conduction, in contrast to the blank MC devices.

  8. Silencing miR-106b accelerates osteogenesis of mesenchymal stem cells and rescues against glucocorticoid-induced osteoporosis by targeting BMP2.

    PubMed

    Liu, Ke; Jing, Ying; Zhang, Wen; Fu, Xuejie; Zhao, Huan; Zhou, Xichao; Tao, Yunxia; Yang, Huilin; Zhang, Yan; Zen, Ke; Zhang, Chenyu; Li, Donghai; Shi, Qin

    2017-04-01

    Osteoporosis is a serious health problem worldwide. MicroRNA is a post-transcriptional regulator of gene expression by either promoting mRNA degradation or interfering with mRNA translation of specific target genes. It plays a significant role in the pathogenesis of osteoporosis. Here, we first demonstrated that miR-106b (miR-106b-5p) negatively regulated osteogenic differentiation of mesenchymal stem cells in vitro. Then, we found that miR-106b expression increased in C57BL/6 mice with glucocorticoid-induced osteoporosis (GIOP), and that silencing of miR-106b signaling protected mice against GIOP through promoting bone formation and inhibiting bone resorption. At last, we showed that miR-106b inhibited osteoblastic differentiation and bone formation partly through directly targeting bone morphogenetic protein 2 (BMP2) both in vitro and in the GIOP model. Together, our findings have identified the role and mechanism of miR-106b in negatively regulating osteogenesis. Inhibition of miR-106b might be a potential new strategy for treating osteoporosis and bone defects. Copyright © 2017. Published by Elsevier Inc.

  9. Perivascular Stem Cells: A Prospectively Purified Mesenchymal Stem Cell Population for Bone Tissue Engineering

    PubMed Central

    James, Aaron W.; Zara, Janette N.; Zhang, Xinli; Askarinam, Asal; Goyal, Raghav; Chiang, Michael; Yuan, Wei; Chang, Le; Corselli, Mirko; Shen, Jia; Pang, Shen; Stoker, David; Wu, Ben

    2012-01-01

    Adipose tissue is an ideal source of mesenchymal stem cells for bone tissue engineering: it is largely dispensable and readily accessible with minimal morbidity. However, the stromal vascular fraction (SVF) of adipose tissue is a heterogeneous cell population, which leads to unreliable bone formation. In the present study, we prospectively purified human perivascular stem cells (PSCs) from adipose tissue and compared their bone-forming capacity with that of traditionally derived SVF. PSCs are a population (sorted by fluorescence-activated cell sorting) of pericytes (CD146+CD34−CD45−) and adventitial cells (CD146−CD34+CD45−), each of which we have previously reported to have properties of mesenchymal stem cells. Here, we found that PSCs underwent osteogenic differentiation in vitro and formed bone after intramuscular implantation without the need for predifferentiation. We next sought to optimize PSCs for in vivo bone formation, adopting a demineralized bone matrix for osteoinduction and tricalcium phosphate particle formulation for protein release. Patient-matched, purified PSCs formed significantly more bone in comparison with traditionally derived SVF by all parameters. Recombinant bone morphogenetic protein 2 increased in vivo bone formation but with a massive adipogenic response. In contrast, recombinant Nel-like molecule 1 (NELL-1; a novel osteoinductive growth factor) selectively enhanced bone formation. These studies suggest that adipose-derived human PSCs are a new cell source for future efforts in skeletal regenerative medicine. Moreover, PSCs are a stem cell-based therapeutic that is readily approvable by the U.S. Food and Drug Administration, with potentially increased safety, purity, identity, potency, and efficacy. Finally, NELL-1 is a candidate growth factor able to induce human PSC osteogenesis. PMID:23197855

  10. N-methyl pyrrolidone/bone morphogenetic protein-2 double delivery with in situ forming implants.

    PubMed

    Karfeld-Sulzer, Lindsay S; Ghayor, Chafik; Siegenthaler, Barbara; de Wild, Michael; Leroux, Jean-Christophe; Weber, Franz E

    2015-04-10

    Bone morphogenetic proteins (BMPs) are growth and differentiation factors involved during development in morphogenesis, organogenesis and later mainly in regeneration processes, in particular in bone where they are responsible for osteoinduction. For more than a decade, recombinant human (rh)BMP-2 has been used in the clinic for lumbar spinal fusion at non-physiological high dosages that appear to be causative for side effects, like male sterility. A possible strategy to reduce the effective amount of rhBMP-2 in the clinic is the co-delivery with an enhancer of BMPs' activity. In an earlier study, we showed that N-methylpyrrolidone (NMP) enhances BMP activity in vitro and in vivo. Here we report on the development of a slow and sustained double delivery of rhBMP-2 and NMP via an in situ forming implant based on poly(lactide-co-glycolide). The results showed that the release of NMP can be adjusted by varying the lactide/glycolide ratio and the polymer's molecular weight. The same applied to rhBMP-2, with release rates that could be sustained from two to three weeks. In the in vivo model of a critical size defect in the calvarial bone of rabbits, the implant containing 50mol% lactide performed better than the one having 75mol% lactide in terms of defect bridging and extent of bony regenerated area. In situ forming implants for the double delivery of the BMP enhancer NMP and rhBMP-2 appear to be promising delivery systems in bone regeneration. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Effectiveness and Complications Associated With Recombinant Human Bone Morphogenetic Protein-2 Augmentation of Foot and Ankle Fusions and Fracture Nonunions.

    PubMed

    Rearick, Timothy; Charlton, Timothy P; Thordarson, David

    2014-08-01

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) has been used to augment bone healing and fusion in a variety of orthopaedic conditions. However, there is a paucity of data evaluating the potential benefits of its use in foot and ankle surgery. The purpose of this study was to investigate the effectiveness and associated complications with the use of rhBMP-2 in high-risk foot and ankle fusions and fracture nonunions. A total of 51 cases in 48 patients undergoing foot and ankle fusions or fracture nonunion revisions and considered at high risk for subsequent nonunion were identified through a retrospective review in which rhBMP-2 was used as an augment for bone healing. Rate of union, time to union, and associated complications were evaluated. Forty-seven of 51 high-risk cases treated with rhBMP-2 united for a per-case union rate of 92.2%. Seventy-eight of 82 individual sites treated with rhBMP-2 united for a per-site union rate of 95.1%. Of the successful unions, the mean time to union was 111 days (95% confidence interval, 101-121). There were no statistically significant differences in time to union with regard to supplementation with bone allograft or autograft or size of rhBMP-2 kit used. Complication rates were low. rhBMP-2 was a safe and apparently effective adjunct to bony union in high-risk foot and ankle surgeries. Further randomized controlled trials are warranted. Level IV, retrospective case series. © The Author(s) 2014.

  12. Breast Cancer Research Program (BCRP) - Predoctoral Traineeship - Elucidating the Role of the Type III Transforming Growth Factor-beta Receptor in Bone Morphogenetic Signaling in Breast Cancer

    DTIC Science & Technology

    2008-03-01

    phosphorylation in the pancreatic cancer cell model, Panc -1 (data not shown). This data emphasize that TβRIII’s role in BMP signaling is likely to be cell... Panc -1 cells were adenovirally infected with TβRIII, followed by BMP-4-induced EMT. The cells were then plated in Matrigel invasion chambers. A...BMP-2, while loss of TβRIII in Panc -1 (pancreatic cancer cells) increased cell sensitivity to BMP-2 and had no effect on MDA-MB-231 (breast cancer

  13. Microcontact printing of BMP-2 and its effect on human chondrocytes behavior

    NASA Astrophysics Data System (ADS)

    Pan, Chang-Jiang; Nie, Yu-Dong

    2010-01-01

    The present study is to investigate human chondrocytes behavior on microcontact printed bone morphogenetic protein-2 (BMP-2) lines on polystyrene (PS) surface. It was found that the cells aligned with BMP lines and expressed type II and VI collagen. The chondrocytes in vitro cultured on BMP lines were elongated, which resulted in altered cell morphology. Taking all these results into consideration, BMP-2 lines enhance cell adhesion, restrict spreading, and increase type II and VI collagen expression. The results represented in this study may be an approach to the problem of engineering reparative cartilage in vitro.

  14. Additively Manufactured 3D Porous Ti-6Al-4V Constructs Mimic Trabecular Bone Structure and Regulate Osteoblast Proliferation, Differentiation and Local Factor Production in a Porosity and Surface Roughness Dependent Manner

    PubMed Central

    Cheng, Alice; Humayun, Aiza; Cohen, David J.; Boyan, Barbara D.; Schwartz, Zvi

    2014-01-01

    Additive manufacturing by laser sintering is able to produce high resolution metal constructs for orthopaedic and dental implants. In this study, we used a human trabecular bone template to design and manufacture Ti-6Al-4V constructs with varying porosity via laser sintering. Characterization of constructs revealed interconnected porosities ranging from 15–70% with compressive moduli of 2063–2954 MPa. These constructs with macro porosity were further surface-treated to create a desirable multi-scale micro-/nano-roughness, which has been shown to enhance the osseointegration process. Osteoblasts (MG63 cells) exhibited high viability when grown on the constructs. Proliferation (DNA) and alkaline phosphatase specific activity (ALP), an early differentiation marker, decreased as porosity increased, while osteocalcin (OCN), a late differentiation marker, as well as osteoprotegerin (OPG), vascular endothelial growth factor (VEGF) and bone morphogenetic proteins 2 and 4 (BMP2, BMP4) increased with increasing porosity. 3D constructs with the highest porosity and surface modification supported the greatest osteoblast differentiation and local factor production. These results indicate that additively manufactured 3D porous constructs mimicking human trabecular bone and produced with additional surface treatment can be customized for increased osteoblast response. Increased factors for osteoblast maturation and differentiation on high porosity constructs suggest the enhanced performance of these surfaces for increasing osseointegration in vivo. PMID:25287305

  15. Effects of polycaprolactone-tricalcium phosphate, recombinant human bone morphogenetic protein-2 and dog mesenchymal stem cells on bone formation: pilot study in dogs.

    PubMed

    Kim, Sun-Jong; Kim, Myung-Rae; Oh, Jin-Sub; Han, Inho; Shin, Sang-Wan

    2009-12-31

    The aim of this study was to evaluate the survival, proliferation, and bone formation of dog mesenchymal stem cells (dMSCs) in the graft material by using Polycaprolactone-tricalcium phosphate (PCL-TCP), auto-fibrin glue (AFG), recombinant human bone morphogenetic protein-2 (rhBMP-2), and dMSCs after a transplantation to the scapula of adult beagle dogs. The subjects were two beagle dogs. Total dose of rhBMP-2 on each block was 10 microg with 50 microg/mg concentration. The cortical bone of the scapula of the dog was removed which was the same size of PCL-TCP block (Osteopore International Pte, Singapore; 5.0x5.0x8.0 mm in size), and the following graft material then was fixed with orthodontic mini-implant, Dual-top (Titanium alloy, Jeil Co. Seoul, Korea). Four experimental groups were prepared for this study, Group 1: PCL-TCP + aFG; Group 2: PCL-TCP + aFG + dMSCs; Group 3: PCL-TCP + aFG + dMSCs + rhBMP-2; Group 4: PCL-TCP + aFG + dMSCs + rhBMP-2 + PCL membrane. The survival or proliferation of dMSCs cells was identified with an extracted tissue through a fluorescence microscope, H-E staining and Von-Kossa staining in two weeks and four weeks after the transplantation. The survival and proliferation of dMSCs were identified through a fluorescence microscope from both Group 1 and Group 2 in two weeks and four weeks after the transplantation. Histological observation also found that the injected cells were proliferating well in the G2, G3, and G4 scaffolds. This study concluded that bone ingrowth occurred in PCL-TCP scaffold which was transplanted with rhBMP-2, and MSCs did not affect bone growth. More sufficient healing time would be needed to recognize effects of dMSCs on bone formation.

  16. Bone regeneration by recombinant human bone morphogenetic protein-2 around immediate implants: a pilot study in rats.

    PubMed

    Matin, Khalrul; Senpuku, Hidenobu; Hanada, Nobuhiro; Ozawa, Hidehiro; Ejiri, Sadakazu

    2003-01-01

    Difficulties relating to bone regeneration that complicate immediate implant placement include buccal and/or lingual fenestrations, primary anchorage of the implants, and the need for protection from functional loading during the osseointegration period. The objective of this pilot study was to evaluate bone regeneration by recombinant human bone morphogenetic protein-2 (rhBMP-2) around immediate implants placed in maxillary sockets in rats. A total of 16 cylindric 0.8 x 1.8-mm commercially pure, solid titanium Implants were placed immediately after gentle extraction of the maxillary first molar teeth of 8 male Wistar rats. The sockets were randomly divided into 3 groups: group 1 (n = 6) received rhBMP-2 with polylactic acid/polyglycolic acid copolymer-coated gelatin sponge carrier; group 2 (n = 5) received only the carrier; and group 3 (n = 5) received no grafting materials following placement The rats were euthanized at 90 days postsurgery for microscopic analysis. In group 1, the implant body remained submerged completely, including the coronal part, which was fully covered by a significant amount (30% of total height) of regenerated cortical bone, even though the implant could easily be pulled out by a tweezer at the time of placement. Close approximation between the implant surface and regenerated bone could also be detected, indicating good bone-to-implant contact. In contrast, only peri-implant bone regeneration occurred in group 2, and an approximate 0.3-mm coronal part of the implant remained exposed. When no grafting materials were used (group 3), almost one third of the total length of the implant was exfoliated out of the socket when no grafting materials were used. Based on previous study and data from 16 sockets of the present study, it could be concluded that rhBMP-2 facilitated the regeneration of bone around immediate implants. In particular, the bone covering the coronal part could have been regenerated shortly after surgery, which helped to maintain the implant body inside the socket during the integration period in rats.

  17. Effects of Arsenic on Osteoblast Differentiation in Vitro and on Bone Mineral Density and Microstructure in Rats

    PubMed Central

    Wu, Cheng-Tien; Lu, Tung-Ying; Chan, Ding-Cheng; Tsai, Keh-Sung; Yang, Rong-Sen

    2014-01-01

    Background: Arsenic is a ubiquitous toxic element and is known to contaminate drinking water in many countries. Several epidemiological studies have shown that arsenic exposure augments the risk of bone disorders. However, the detailed effect and mechanism of inorganic arsenic on osteoblast differentiation of bone marrow stromal cells and bone loss still remain unclear. Objectives: We investigated the effects and mechanism of arsenic on osteoblast differentiation in vitro and evaluated bone mineral density (BMD) and bone microstructure in rats at doses relevant to human exposure from drinking water. Methods: We used a cell model of rat primary bone marrow stromal cells (BMSCs) and a rat model of long-term exposure with arsenic-contaminated drinking water, and determined bone microstructure and BMD in rats by microcomputed tomography (μCT). Results: We observed significant attenuation of osteoblast differentiation after exposure of BMSCs to arsenic trioxide (0.5 or 1 μM). After arsenic treatment during differentiation, expression of runt-related transcription factor-2 (Runx2), bone morphogenetic protein-2 (BMP-2), and osteocalcin in BMSCs was inhibited and phosphorylation of enhanced extracellular signal-regulated kinase (ERK) was increased. These altered differentiation-related molecules could be reversed by the ERK inhibitor PD98059. Exposure of rats to arsenic trioxide (0.05 or 0.5 ppm) in drinking water for 12 weeks altered BMD and microstructure, decreased Runx2 expression, and increased ERK phosphorylation in bones. In BMSCs isolated from arsenic-treated rats, osteoblast differentiation was inhibited. Conclusions: Our results suggest that arsenic is capable of inhibiting osteoblast differentiation of BMSCs via an ERK-dependent signaling pathway and thus increasing bone loss. Citation: Wu CT, Lu TY, Chan DC, Tsai KS, Yang RS, Liu SH. 2014. Effects of arsenic on osteoblast differentiation in vitro and on bone mineral density and microstructure in rats. Environ Health Perspect 122:559–565; http://dx.doi.org/10.1289/ehp.1307832 PMID:24531206

  18. 3D printing of hybrid biomaterials for bone tissue engineering: Calcium-polyphosphate microparticles encapsulated by polycaprolactone.

    PubMed

    Neufurth, Meik; Wang, Xiaohong; Wang, Shunfeng; Steffen, Renate; Ackermann, Maximilian; Haep, Natalie D; Schröder, Heinz C; Müller, Werner E G

    2017-12-01

    Here we describe the formulation of a morphogenetically active bio-ink consisting of amorphous microparticles (MP) prepared from Ca 2+ and the physiological inorganic polymer, polyphosphate (polyP). Those MP had been fortified by mixing with poly-ε-caprolactone (PCL) to allow 3D-bioprinting. The resulting granular PCL/Ca-polyP-MP hybrid material, liquefied by short-time heating to 100 °C, was used for the 3D-printing of tissue-like scaffolds formed by strands with a thickness of 400 µm and a stacked architecture leaving ≈0.5 mm 2 -sized open holes enabling cell migration. The printed composite scaffold turned out to combine suitable biomechanical properties (Young's modulus of 1.60 ± 0.1 GPa; Martens hardness of 153 ± 28 MPa), matching those of cortical and trabecular bone, with morphogenetic activity. This scaffold was capable of attracting and promoting the growth of human bone-related SaOS-2 cells as demonstrated by staining for cell viability (Calcein AM), cell density (DRAQ5) and SEM studies. Furthermore, the hybrid material was demonstrated to upregulate the steady-state-expression of the cell migration-inducing chemokine SDF-1α. EDX analysis and FTIR measurements revealed the presence of hydroxyapatite in the mineral deposits formed on the scaffold surface. Based on the results we conclude that granular PCL/Ca-polyP-MP hybrid material is suitable for the fabrication of bioprintable scaffold which comprises not only biomechanical stability but also morphogenetic potential. In present-day regenerative engineering efforts, biomaterial- and cell-based strategies are proposed that meet the required functional and spatial characteristics and variations, especially in the transition regions between soft (cartilage, tendon or ligament) and hard (bone) tissues. In a biomimetic approach we succeeded to fabricate amorphous Ca-polyP nanoparticles/microparticles which are highly biocompatible. Together with polycaprolactone (PCL), polyP can be bio-printed. This hybrid material attracts the cells, as documented optically as well as by a gene-expression studies. Since PCL is already a FDA-approved organic and inert polymer and polyP a physiological biologically active component this new bio-hybrid material has the potential to restore physiological functions, including bone remodelling and regeneration if used as implant. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  19. Endochondral bone formation in embryonic mouse pre-metatarsals

    NASA Technical Reports Server (NTRS)

    Klement, B. J.; Spooner, B. S.

    1992-01-01

    Long term exposure to a reduced gravitational environment has a deleterious effect on bone. The developmental events which occur prior to initial bone deposition will provide insight into the regulation of mature bone physiology. We have characterized a system in which the events preceding bone formation take place in an isolated in vitro organ culture environment. We show that cultured pre-metatarsal tissue parallels development of pre-metatarsal tissue in the embryo. Both undergo mesenchyme differentiation and morphogenesis to form a cartilage rod, which resembles the future bone, followed by terminal chondrocyte differentiation in a definite morphogenetic pattern. These sequential steps occur prior to osteoblast maturation and bone matrix deposition in the developing organism. Alkaline phosphatase (ALP) activity is a distinctive enzymatic marker for mineralizing tissues. We have measured this activity throughout pre-metatarsal development and show (a) where in the tissue it is predominantly found, and (b) that this is indeed the mineralizing isoform of the enzyme.

  20. Technical Report: Correlation Between the Repair of Cartilage and Subchondral Bone in an Osteochondral Defect Using Bilayered, Biodegradable Hydrogel Composites.

    PubMed

    Lu, Steven; Lam, Johnny; Trachtenberg, Jordan E; Lee, Esther J; Seyednejad, Hajar; van den Beucken, Jeroen J J P; Tabata, Yasuhiko; Kasper, F Kurtis; Scott, David W; Wong, Mark E; Jansen, John A; Mikos, Antonios G

    2015-12-01

    The present work investigated correlations between cartilage and subchondral bone repair, facilitated by a growth factor-delivering scaffold, in a rabbit osteochondral defect model. Histological scoring indices and microcomputed tomography morphological parameters were used to evaluate cartilage and bone repair, respectively, at 6 and 12 weeks. Correlation analysis revealed significant associations between specific cartilage indices and subchondral bone parameters that varied with location in the defect (cortical vs. trabecular region), time point (6 vs. 12 weeks), and experimental group (insulin-like growth factor-1 only, bone morphogenetic protein-2 only, or both growth factors). In particular, significant correlations consistently existed between cartilage surface regularity and bone quantity parameters. Overall, correlation analysis between cartilage and bone repair provided a fuller understanding of osteochondral repair and can help drive informed studies for future osteochondral regeneration strategies.

  1. Safety and efficacy of use of demineralised bone matrix in orthopaedic and trauma surgery.

    PubMed

    Dinopoulos, Haralampos T H; Giannoudis, Peter V

    2006-11-01

    Demineralised bone matrix (DBM) acts as an osteoconductive, and possibly as an osteoinductive, material. It is widely used in orthopaedic, neurosurgical, plastic and dental areas. More than 500,000 bone grafting procedures with DBM are performed annually in the US. It does not offer structural support, but it is well suited for filling bone defects and cavities. The osteoinductive nature of DBM is presumably attributed to the presence of matrix-associated bone morphogenetic proteins (BMPs) and growth factors, which are made available to the host environment by the demineralisation process. Clinical results have not been uniformly favourable; however, a variable clinical response is attributed partly to nonuniform processing methods found among numerous bone banks and commercial suppliers. DBMs remain reasonably safe and effective products. The ultimate safe bone-graft substitute, one that is osteoconductive, osteoinductive, osteogenic and mechanically strong, remains elusive.

  2. Tridax procumbens flavonoids promote osteoblast differentiation and bone formation.

    PubMed

    Al Mamun, Md Abdullah; Hosen, Mohammad Jakir; Islam, Kamrul; Khatun, Amina; Alam, M Masihul; Al-Bari, Md Abdul Alim

    2015-11-18

    Tridax procumbens flavonoids (TPFs) are well known for their medicinal properties among local natives. Besides traditionally used for dropsy, anemia, arthritis, gout, asthma, ulcer, piles, and urinary problems, it is also used in treating gastric problems, body pain, and rheumatic pains of joints. TPFs have been reported to increase osteogenic functioning in mesenchymal stem cells. Our previous study showed that TPFs were significantly suppressed the RANKL-induced differentiation of osteoclasts and bone resorption. However, the effects of TPFs to promote osteoblasts differentiation and bone formation remain unclear. TPFs were isolated from Tridax procumbens and investigated for their effects on osteoblasts differentiation and bone formation by using primary mouse calvarial osteoblasts. TPFs promoted osteoblast differentiation in a dose-dependent manner demonstrated by up-regulation of alkaline phosphatase and osteocalcin. TPFs also upregulated osteoblast differentiation related genes, including osteocalcin, osterix, and Runx2 in primary osteoblasts. TPFs treated primary osteoblast cells showed significant upregulation of bone morphogenetic proteins (BMPs) including Bmp-2, Bmp-4, and Bmp-7. Addition of noggin, a BMP specific-antagonist, inhibited TPFs induced upregulation of the osteocalcin, osterix, and Runx2. Our findings point towards the induction of osteoblast differentiation by TPFs and suggested that TPFs could be a potential anabolic agent to treat patients with bone loss-associated diseases such as osteoporosis.

  3. Noni leaf and black tea enhance bone regeneration in estrogen-deficient rats.

    PubMed

    Shalan, Nor Aijratul Asikin Mohd; Mustapha, Noordin M; Mohamed, Suhaila

    2017-01-01

    Black tea and Nonileaf are among the dietary compounds that can benefit patients with bone resorption disorders. Their bone regeneration effects and their mechanisms were studied in estrogen-deficient rats. Noni leaves (three doses) and black tea water extracts were fed to ovariectomized rats for 4 mo, and their effects (analyzed via mechanical measurements, micro-computed tomography scan, and reverse transcriptase polymerase chain reaction mRNA) were compared with Remifemin (a commercial phytoestrogen product from black cohosh). The water extracts (dose-dependently for noni leaves) increased bone regeneration biomarker (runt-related transcription factor 2, bone morphogenetic protein 2, osteoprotegerin, estrogen receptor 1 [ESR1], collagen type I alpha 1A) expressions and reduced the inflammatory biomarkers (interleukin-6, tumor necrosis factor-α, nuclear factor [NF]-κB, and receptor activator of NF-κB ligand) mRNA expressions/levels in the rats. The extracts also improved bone physical and mechanical properties. The extracts demonstrated bone regeneration through improving bone size and structure, bone mechanical properties (strength and flexibility), and bone mineralization and density. The catechin-rich extract favored bone regeneration and suppressed bone resorption. The mechanisms involved enhancing osteoblast generation and survival, inhibiting osteoclast growth and activities, suppressing inflammation, improving bone collagen synthesis and upregulating ESR1 expression to augment phytoestrogenic effects. Estrogen deficiency bone loss and all extracts studied (best effect from Morinda leaf at 300 mg/kg body weight) mitigated the loss, indicating benefits for the aged and menopausal women. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Comparison of the effects of recombinant human bone morphogenetic protein-2 and -9 on bone formation in rat calvarial critical-size defects.

    PubMed

    Nakamura, Toshiaki; Shirakata, Yoshinori; Shinohara, Yukiya; Miron, Richard J; Hasegawa-Nakamura, Kozue; Fujioka-Kobayashi, Masako; Noguchi, Kazuyuki

    2017-12-01

    Among bone morphogenetic protein (BMP) family members, BMP-2 and BMP-9 have demonstrated potent osteoinductive potential. However, in vivo differences in their potential for bone regeneration remain unclear. The present study aimed to compare the effects of recombinant human (rh) BMP-2 and rhBMP-9 on bone formation in rat calvarial critical-size defects (CSD). Twenty-eight Wistar rats surgically received two calvarial defects bilaterally in each parietal bone. Defects (n = 56) were allocated into four groups: absorbable collagen sponge (ACS) alone, rhBMP-2 with ACS (rhBMP-2/ACS), rhBMP-9/ACS, or sham surgery (control), on the condition that the treatments of rhBMP-2/ACS and rhBMP-9/ACS, or the same treatments were not included in the same animal. Animals were sacrificed at 2 and 8 weeks post-surgery. The calvarial defects were analyzed for bone volume (BV) by micro-computed tomography and for percentages of defect closure (DC/DL), newly formed bone area (NBA/TA), bone marrow area (BMA/NBA), adipose tissue area (ATA/NBA), central bone height (CBH), and marginal bone height (MBH) by histomorphometric analysis. The BV in the rhBMP-2/ACS group (5.44 ± 3.65 mm 3 , n = 7) was greater than the other groups at 2 weeks post-surgery, and the rhBMP-2/ACS and rhBMP-9/ACS groups (18.17 ± 2.51 and 16.30 ± 2.46 mm 3 , n = 7, respectively) demonstrated significantly greater amounts of BV compared with the control and ACS groups (6.02 ± 2.90 and 9.30 ± 2.75 mm 3 , n = 7, respectively) at 8 weeks post-surgery. The rhBMP-2/ACS and rhBMP-9/ACS groups significantly induced new bone formation compared to the control and ACS groups at 8 weeks post-surgery. However, there were no statistically significant differences found between the rhBMP-2/ACS and rhBMP-9/ACS groups in any of the histomorphometric parameters. The ATA/NBA in the rhBMP-2/ACS group (9.24 ± 3.72%, n = 7) was the highest among the treatment groups at 8 weeks post-surgery. Within the limits of this study, it can be concluded that rhBMP-2/ACS induced a slight early increase in new bone formation at 2 weeks and that rhBMP-9/ACS provided comparable new bone formation to rhBMP-2/ACS with less adipose tissues after a healing period of 8 weeks in rat CSD. RhBMP-9/ACS treatment provided new bone formation with less adipose tissues compared with rhBMP-2/ACS.

  5. Enhancing of Osseointegration with Propolis-Loaded TiO2 Nanotubes in Rat Mandible for Dental Implants

    PubMed Central

    Somsanith, Nithideth; Jang, Young-Seok; Lee, Young-Hee; Yi, Ho-Keun; Kim, Kyoung-A; Bae, Tae-Sung; Lee, Min-Ho

    2018-01-01

    TiO2 nanotubes (TNT) formation is beneficial for improving bone cell–material interaction and drug delivery for Ti dental implants. Among the natural drugs to be installed in TNT, selected propolis has antibacterial and anti-inflammatory properties. It is a resinous natural product which is collected by the honeybees from the various types of plants with their salivary enzymes. This study concludes that TNT loaded with a propolis (PL-TNT-Ti) dental implant has the ability to improve osseointegration. The propolis particles were embedded within the TNT or adhered to the top. In a cytotoxicity test using osteoblast, PL-TNT-Ti group exhibited an increased cell proliferation and differentiation. A Sprague Dawley rat mandibular model was used to evaluate the osseointegration and bone bonding of TNT or PL-TNT-Ti. From the µ-CT and hematoxylin and eosin (HE) histological results after implantation at 1 and 4 weeks to rat mandibular, an increase in the extent of new bone formation and mineral density around the PL-TNT-Ti implant was confirmed. The Masson’s trichrome staining showed the expression of well-formed collagenous for bone formation on the PL-TNT-Ti. Immunohistochemistry staining indicate that bone morphogenetic proteins (BMP-2 and BMP-7) around the PL-TNT-Ti increased the expression of collagen fibers and of osteogenic differentiation whereas the expression of inflammatory cytokine such as interleukin-1 beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) is decreased. PMID:29301269

  6. Segmental bone defects: from cellular and molecular pathways to the development of novel biological treatments

    PubMed Central

    Pneumaticos, Spyros G; Triantafyllopoulos, Georgios K; Basdra, Efthimia K; Papavassiliou, Athanasios G

    2010-01-01

    Abstract Several conditions in clinical orthopaedic practice can lead to the development of a diaphyseal segmental bone defect, which cannot heal without intervention. Segmental bone defects have been traditionally treated with bone grafting and/or distraction osteogenesis, methods that have many advantages, but also major drawbacks, such as limited availability, risk of disease transmission and prolonged treatment. In order to overcome such limitations, biological treatments have been developed based on specific pathways of bone physiology and healing. Bone tissue engineering is a dynamic field of research, combining osteogenic cells, osteoinductive factors, such as bone morphogenetic proteins, and scaffolds with osteoconductive and osteoinductive attributes, to produce constructs that could be used as bone graft substitutes for the treatment of segmental bone defects. Scaffolds are usually made of ceramic or polymeric biomaterials, or combinations of both in composite materials. The purpose of the present review is to discuss in detail the molecular and cellular basis for the development of bone tissue engineering constructs. PMID:20345845

  7. BMP2-loaded hollow hydroxyapatite microspheres exhibit enhanced osteoinduction and osteogenicity in large bone defects

    PubMed Central

    Xiong, Long; Zeng, Jianhua; Yao, Aihua; Tu, Qiquan; Li, Jingtang; Yan, Liang; Tang, Zhiming

    2015-01-01

    The regeneration of large bone defects is an osteoinductive, osteoconductive, and osteogenic process that often requires a bone graft for support. Limitations associated with naturally autogenic or allogenic bone grafts have demonstrated the need for synthetic substitutes. The present study investigates the feasibility of using novel hollow hydroxyapatite microspheres as an osteoconductive matrix and a carrier for controlled local delivery of bone morphogenetic protein 2 (BMP2), a potent osteogenic inducer of bone regeneration. Hollow hydroxyapatite microspheres (100±25 μm) with a core (60±18 μm) and a mesoporous shell (180±42 m2/g surface area) were prepared by a glass conversion technique and loaded with recombinant human BMP2 (1 μg/mg). There was a gentle burst release of BMP2 from microspheres into the surrounding phosphate-buffered saline in vitro within the initial 48 hours, and continued at a low rate for over 40 days. In comparison with hollow hydroxyapatite microspheres without BMP2 or soluble BMP2 without a carrier, BMP2-loaded hollow hydroxyapatite microspheres had a significantly enhanced capacity to reconstitute radial bone defects in rabbit, as shown by increased serum alkaline phosphatase; quick and complete new bone formation within 12 weeks; and great biomechanical flexural strength. These results indicate that BMP2-loaded hollow hydroxyapatite microspheres could be a potential new option for bone graft substitutes in bone regeneration. PMID:25609957

  8. 20p12.3 microdeletion predisposes to Wolff–Parkinson–White syndrome with variable neurocognitive deficits

    USDA-ARS?s Scientific Manuscript database

    Wolff–Parkinson–White syndrome (WPW) is a bypass re-entrant tachycardia that results from an abnormal connection between the atria and ventricles. Mutations in PRKAG2 have been described in patients with familial WPW syndrome and hypertrophic cardiomyopathy. Based on the role of bone morphogenetic p...

  9. Processing of hemojuvelin requires retrograde trafficking to the Golgi in HepG2 cells.

    PubMed

    Maxson, Julia E; Enns, Caroline A; Zhang, An-Sheng

    2009-02-19

    Hemojuvelin (HJV) was recently identified as a critical regulator of iron homeostasis. It is either associated with cell membranes through a glycosylphosphatidylinositol anchor or released as a soluble form. Membrane-anchored HJV acts as a coreceptor for bone morphogenetic proteins and activates the transcription of hepcidin, a hormone that regulates iron efflux from cells. Soluble HJV antagonizes bone morphogenetic protein signaling and suppresses hepcidin expression. In this study, we examined the trafficking and processing of HJV. Cellular HJV reached the plasma membrane without obtaining complex oligosaccharides, indicating that HJV avoided Golgi processing. Secreted HJV, in contrast, has complex oligosaccharides and can be derived from HJV with high-mannose oligosaccharides at the plasma membrane. Our results support a model in which retrograde trafficking of HJV before cleavage is the predominant processing pathway. Release of HJV requires it to bind to the transmembrane receptor neogenin. Neogenin does not, however, play a role in HJV trafficking to the cell surface, suggesting that it could be involved either in retrograde trafficking of HJV or in cleavage leading to HJV release.

  10. Processing of hemojuvelin requires retrograde trafficking to the Golgi in HepG2 cells

    PubMed Central

    Maxson, Julia E.; Enns, Caroline A.

    2009-01-01

    Hemojuvelin (HJV) was recently identified as a critical regulator of iron homeostasis. It is either associated with cell membranes through a glycosylphosphatidylinositol anchor or released as a soluble form. Membrane-anchored HJV acts as a coreceptor for bone morphogenetic proteins and activates the transcription of hepcidin, a hormone that regulates iron efflux from cells. Soluble HJV antagonizes bone morphogenetic protein signaling and suppresses hepcidin expression. In this study, we examined the trafficking and processing of HJV. Cellular HJV reached the plasma membrane without obtaining complex oligosaccharides, indicating that HJV avoided Golgi processing. Secreted HJV, in contrast, has complex oligosaccharides and can be derived from HJV with high-mannose oligosaccharides at the plasma membrane. Our results support a model in which retrograde trafficking of HJV before cleavage is the predominant processing pathway. Release of HJV requires it to bind to the transmembrane receptor neogenin. Neogenin does not, however, play a role in HJV trafficking to the cell surface, suggesting that it could be involved either in retrograde trafficking of HJV or in cleavage leading to HJV release. PMID:19029439

  11. Constitutively Active Akt Induces Ectodermal Defects and Impaired Bone Morphogenetic Protein Signaling

    PubMed Central

    Segrelles, Carmen; Moral, Marta; Lorz, Corina; Santos, Mirentxu; Lu, Jerry; Cascallana, José Luis; Lara, M. Fernanda; Carbajal, Steve; Martínez-Cruz, Ana Belén; García-Escudero, Ramón; Beltran, Linda; Segovia, José C.; Bravo, Ana

    2008-01-01

    Aberrant activation of the Akt pathway has been implicated in several human pathologies including cancer. However, current knowledge on the involvement of Akt signaling in development is limited. Previous data have suggested that Akt-mediated signaling may be an essential mediator of epidermal homeostasis through cell autonomous and noncell autonomous mechanisms. Here we report the developmental consequences of deregulated Akt activity in the basal layer of stratified epithelia, mediated by the expression of a constitutively active Akt1 (myrAkt) in transgenic mice. Contrary to mice overexpressing wild-type Akt1 (Aktwt), these myrAkt mice display, in a dose-dependent manner, altered development of ectodermally derived organs such as hair, teeth, nails, and epidermal glands. To identify the possible molecular mechanisms underlying these alterations, gene profiling approaches were used. We demonstrate that constitutive Akt activity disturbs the bone morphogenetic protein-dependent signaling pathway. In addition, these mice also display alterations in adult epidermal stem cells. Collectively, we show that epithelial tissue development and homeostasis is dependent on proper regulation of Akt expression and activity. PMID:17959825

  12. Purification of bone morphogenetic protein-2 from refolding mixtures using mixed-mode membrane chromatography.

    PubMed

    Gieseler, Gesa; Pepelanova, Iliyana; Stuckenberg, Lena; Villain, Louis; Nölle, Volker; Odenthal, Uwe; Beutel, Sascha; Rinas, Ursula; Scheper, Thomas

    2017-01-01

    In this study, we present the development of a process for the purification of recombinant human bone morphogenetic protein-2 (rhBMP-2) using mixed-mode membrane chromatography. RhBMP-2 was produced as inclusion bodies in Escherichia coli. In vitro refolding using rapid dilution was carried out according to a previously established protocol. Different membrane chromatography phases were analyzed for their ability to purify BMP-2. A membrane phase with salt-tolerant properties resulting from mixed-mode ligand chemistry was able to selectively purify BMP-2 dimer from refolding mixtures. No further purification or polishing steps were necessary and high product purity was obtained. The produced BMP-2 exhibited a biological activity of 7.4 × 10 5  U/mg, comparable to commercial preparations. Mixed-mode membrane chromatography can be a valuable tool for the direct purification of proteins from solutions with high-conductivity, for example refolding buffers. In addition, in this particular case, it allowed us to circumvent the use of heparin-affinity chromatography, thus allowing the design of an animal-component-free process.

  13. Expression of bone morphogenetic proteins and Msx genes during root formation.

    PubMed

    Yamashiro, T; Tummers, M; Thesleff, I

    2003-03-01

    Like crown development, root formation is also regulated by interactions between epithelial and mesenchymml tissues. Bone morphogenetic proteins (BMPs), together with the transcription factors Msx1 and Msx2, play important roles in these interactions during early tooth morphogenesis. To investigate the involvement of this signaling pathway in root development, we analyzed the expression patterns of Bmp2, Bmp3, Bmp4, and Bmp7 as well as Msx1 and Msx2 in the roots of mouse molars. Bmp4 was expressed in the apical mesenchyme and Msx2 in the root sheath. However, Bmps were not detected in the root sheath epithelium, and Msx transcripts were absent from the underlying mesenchyme. These findings indicate that this Bmp signaling pathway, required for tooth initiation, does not regulate root development, but we suggest that root shape may be regulated by a mechanism similar to that regulating crown shape in cap-stage tooth germs. Msx2 expression continued in the epithelial cell rests of Malassez, and the nearby cementoblasts intensely expressed Bmp3, which may regulate some functions of the fragmented epithelium.

  14. Regulators and effectors of bone morphogenetic protein signalling in the cardiovascular system.

    PubMed

    Luo, Jiang-Yun; Zhang, Yang; Wang, Li; Huang, Yu

    2015-07-15

    Bone morphogenetic proteins (BMPs) play key roles in the regulation of cell proliferation, differentiation and apoptosis in various tissues and organs, including the cardiovascular system. BMPs signal through both Smad-dependent and -independent cascades to exert a wide spectrum of biological activities. Cardiovascular disorders such as abnormal angiogenesis, atherosclerosis, pulmonary hypertension and cardiac hypertrophy have been linked to aberrant BMP signalling. To correct the dysregulated BMP signalling in cardiovascular pathogenesis, it is essential to get a better understanding of how the regulators and effectors of BMP signalling control cardiovascular function and how the dysregulated BMP signalling contributes to cardiovascular dysfunction. We hence highlight several key regulators of BMP signalling such as extracellular regulators of ligands, mechanical forces, microRNAs and small molecule drugs as well as typical BMP effectors like direct downstream target genes, mitogen-activated protein kinases, reactive oxygen species and microRNAs. The insights into these molecular processes will help target both the regulators and important effectors to reverse BMP-associated cardiovascular pathogenesis. © 2015 The Authors. The Journal of Physiology © 2015 The Physiological Society.

  15. Transgenic medaka fish as models to analyze bone homeostasis under micro-gravity conditions in vivo

    NASA Astrophysics Data System (ADS)

    Winkler, C.; Wagner, T.; Renn, J.; Goerlich, R.; Schartl, M.

    Long-term space flight and microgravity results in bone loss that can be explained by reduced activity of bone-forming osteoblast cells and/or an increase in activity of bone resorbing osteoclast cells. Osteoprotegerin (OPG), a secreted protein of 401 amino acids, has been shown to regulate the balance between osteoblast and osteoclast formation and thereby warrants constant bone mass under normal gravitational conditions. Consistent with this, earlier reports using transgenic mice have shown that increased activation of OPG leads to exc essive bone formation (osteopetrosis), while inactivation of OPG leads to bone loss (osteoporosis). Importantly, it has recently been reported that expression of murine OPG is regulated by vector averaged gravity (Kanematsu et al., 2002, Bone 30, p553). The small bony fish medaka (Oryzias latipes ) has attracted increasing attention as genetic model system to study developmental and pathological processes. To analyze the molecular mechanisms of bone formation in this small vertebrate, we have isolated two related genes, opr-1 and opr -2, from medaka. Our phylogenetic analysis revealed that both genes originated from a common ancestor by fish-specific gene duplication and represent the orthologs of the mammalian OPG gene. Both opr genes are differentially expressed during embryonic and larval development, in adult tissues and in cultured primary osteoblast cells. We have characterized their promoter regions and identified consensus binding sites for transcription factors of the bone-morphogenetic-protein (BMP) p thway and for core-binding-factor-1Aa (cbfa1). Cbfa1 has been shown to be the key regulator of OPG expression during several steps of osteoblast differentiation in mammals. This opens the possibility that the mechanisms controlling bone formation in teleost fish and higher vertebrates are regulated by related mechanisms. We are currently generating transgenic medakafish expressing a GFP reporter gene under control of the teleost OPG promoter in order to visualize osteoblast activity in a living organism under different gravity conditions. This work is supported by the German Aerospace Center, DLR.

  16. Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty.

    PubMed

    Tian, Xiao-bin; Sun, Li; Yang, Shu-hua; Zhang, Yu-kun; Hu, Ru-yin; Fu, De-hao

    2008-04-20

    Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects. Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation. The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone formation rate and antibending strength of group A was significantly higher than those of group B and C. The defects in blank control were not healed. The hBMP2 gene activated nanobone putty exhibited osteoinductive ability, and had a better bone defect repair capability than that of nanobone putty only.

  17. Effects of hydrostatic pressure on cytoskeleton and BMP-2, TGF-beta, SOX-9 production in rat temporomandibular synovial fibroblasts.

    PubMed

    Wu, M-J; Gu, Z-Y; Sun, W

    2008-01-01

    Recent experimental evidence has suggested that pressure may play an important role in the pathogenesis of arthritic diseases such as temporomandibular disorders (TMDs), rheumatic diseases and osteoarthritis. This study examines the effects of hydrostatic pressure (HP) on cytoskeleton and protein production of bone morphogenetic protein-2 (BMP-2), transforming growth factor-beta (TGF-beta) and the SRY HMG box related gene 9 (SOX-9) in synovial fibroblasts (SFs) of rat temporomandibular joint (TMJ). SFs derived from rat TMJ were grown to confluence in Dulbecco's modified Eagle medium supplemented with 15% fetal calf serum. The monolayer of SFs was subjected to different HPs (0, 30, 60, and 90kPa) by an in-house designed pressure chamber for 12h. Changes of cell morphology were observed by fluorescent microscope. Production of TGF-beta, BMP-2 and SOX-9 was examined by immunocytochemical assay and western blot. Compared with the untreated control, the cellular actin configuration of SFs became elongated and more intense F-actin stress fiber staining was observed after HP loading. Exposure of SFs to HP for 12h resulted in significant up-regulation of BMP-2 by 46, 54, and 66% at 30, 60, and 90kPa, respectively, whilst TGF-beta increased by 11, 19, and 28% at 30, 60, and 90kPa, respectively. HP also induced the increase of SOX-9 by 72% at 30kPa and 83% at 60kPa, but only 54% at 90kPa. The obtained data suggest that HP induced the alteration of cytoskeleton and bone-morphogenetic-related proteins' production of SFs, which may influence the pathological condition of TMDs.

  18. Bone morphogenetic protein-7 (BMP-7) augments insulin sensitivity in mice with type II diabetes mellitus by potentiating PI3K/AKT pathway.

    PubMed

    Chattopadhyay, Tandrika; Singh, Rajiv Ranjan; Gupta, Sarika; Surolia, Avadhesha

    2017-03-01

    A direct link between development of insulin resistance and the presence of chronic inflammation, in case of obesity exists, with cytokines playing an important role in glucose metabolism. Members of TGF-β superfamily, including bone morphogenetic proteins (BMPs), have been shown to be involved in islet morphogenesis, establishment of β-cell mass and adipose cell fate determination. Here, we demonstrate a novel and direct role of BMP-4 and -7 in the regulation of glucose homeostasis and insulin resistance. An age-dependent increase in serum BMP-4 and decrease in serum BMP-7 levels was observed in animal models of type II diabetes. In this study, BMP-7 and -4 have been demonstrated to have antagonistic effects on insulin signaling and thereby on glucose homeostasis. BMP-7 augmented glucose uptake in the insulin sensitive tissues such as the adipose and muscle by increasing Glut4 translocation to the plasma membrane through phosphorylation and activation of PDK1 and Akt, and phosphorylation and translocation of FoxO1 to the cytoplasm in liver/HepG2 cells. Restoration of BMP-7 levels in serum of diabetic animals resulted in decreased blood glucose levels in contrast to age matched untreated control groups, opening up a new therapeutic avenue for diabetes. On the contrary, BMP-4 inhibited insulin signaling through activation of PKC-θ isoform, and resulted in insulin resistance through the attenuation of insulin signaling. BMP-7 therefore is an attractive candidate for tackling a multifaceted disease such as diabetes, since it not only reduces body fat, but also strengthens insulin signaling, causing improved glucose uptake and ameliorating peripheral insulin resistance. © 2017 BioFactors, 43(2):195-209, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

  19. Tribulus terrestris Alters the Expression of Growth Differentiation Factor 9 and Bone Morphogenetic Protein 15 in Rabbit Ovaries of Mothers and F1 Female Offspring.

    PubMed

    Abadjieva, Desislava; Kistanova, Elena

    2016-01-01

    Although previous research has demonstrated the key role of the oocyte-derived factors, bone morphogenetic protein (BMP) 15 and growth differentiation factor (GDF) 9, in follicular development and ovulation, there is a lack of knowledge on the impact of external factors, which females are exposed to during folliculogenesis, on their expression. The present study investigated the effect of the aphrodisiac Tribulus terrestris on the GDF9 and BMP15 expression in the oocytes and cumulus cells at mRNA and protein levels during folliculogenesis in two generations of female rabbits. The experiment was conducted with 28 New Zealand rabbits. Only the diet of the experimental mothers group was supplemented with a dry extract of T. terrestris for the 45 days prior to insemination. The expression of BMP15 and GDF9 genes in the oocytes and cumulus cells of mothers and F1 female offspring was analyzed using real-time polymerase chain reaction (RT-PCR). The localization of the GDF9 and BMP15 proteins in the ovary tissues was determined by immunohistochemical analysis. The BMP15 and GDF9 transcripts were detected in the oocytes and cumulus cells of rabbits from all groups. T. terrestris caused a decrease in the BMP15 mRNA level in the oocytes and an increase in the cumulus cells. The GDF9 mRNA level increased significantly in both oocytes and cumulus cells. The downregulated expression of BMP15 in the treated mothers' oocytes was inherited in the F1 female offspring born to treated mothers. BMP15 and GDF9 show a clearly expressed sensitivity to the bioactive compounds of T. terrestris.

  20. Tribulus terrestris Alters the Expression of Growth Differentiation Factor 9 and Bone Morphogenetic Protein 15 in Rabbit Ovaries of Mothers and F1 Female Offspring

    PubMed Central

    2016-01-01

    Although previous research has demonstrated the key role of the oocyte-derived factors, bone morphogenetic protein (BMP) 15 and growth differentiation factor (GDF) 9, in follicular development and ovulation, there is a lack of knowledge on the impact of external factors, which females are exposed to during folliculogenesis, on their expression. The present study investigated the effect of the aphrodisiac Tribulus terrestris on the GDF9 and BMP15 expression in the oocytes and cumulus cells at mRNA and protein levels during folliculogenesis in two generations of female rabbits. The experiment was conducted with 28 New Zealand rabbits. Only the diet of the experimental mothers group was supplemented with a dry extract of T. terrestris for the 45 days prior to insemination. The expression of BMP15 and GDF9 genes in the oocytes and cumulus cells of mothers and F1 female offspring was analyzed using real-time polymerase chain reaction (RT-PCR). The localization of the GDF9 and BMP15 proteins in the ovary tissues was determined by immunohistochemical analysis. The BMP15 and GDF9 transcripts were detected in the oocytes and cumulus cells of rabbits from all groups. T. terrestris caused a decrease in the BMP15 mRNA level in the oocytes and an increase in the cumulus cells. The GDF9 mRNA level increased significantly in both oocytes and cumulus cells. The downregulated expression of BMP15 in the treated mothers’ oocytes was inherited in the F1 female offspring born to treated mothers. BMP15 and GDF9 show a clearly expressed sensitivity to the bioactive compounds of T. terrestris. PMID:26928288

  1. Growth differentiation factor 3 is induced by bone morphogenetic protein 6 (BMP-6) and BMP-7 and increases luteinizing hormone receptor messenger RNA expression in human granulosa cells.

    PubMed

    Shi, Jia; Yoshino, Osamu; Osuga, Yutaka; Akiyama, Ikumi; Harada, Miyuki; Koga, Kaori; Fujimoto, Akihisa; Yano, Tetsu; Taketani, Yuji

    2012-04-01

    To examine the relevance of growth differentiation factor 3 (GDF-3) and bone morphogenetic protein (BMP) cytokines in human ovary. Molecular studies. Research laboratory. Eight women undergoing salpingo-oophorectomy and 30 women undergoing ovarian stimulation for in vitro fertilization. Localizing GDF-3 protein in human ovaries; granulosa cells (GC) cultured with GDF-3, BMP-6, or BMP-7 followed by RNA extraction. The localization of GDF-3 protein in normal human ovaries via immunohistochemical analysis, GDF-3 messenger RNA (mRNA) expression evaluation via quantitative real-time reverse transcription and polymerase chain reaction (RT-PCR), and evaluation of the effect of GDF-3 on leuteinizing hormone (LH) receptor mRNA expression via quantitative real-time RT-PCR. In the ovary, BMP cytokines, of the transforming growth factor beta (TGF-β) superfamily, are known as a luteinization inhibitor by suppressing LH receptor expression in GC. Growth differentiation factor 3, a TGF-β superfamily cytokine, is recognized as an inhibitor of BMP cytokines in other cells. Immunohistochemical analysis showed that GDF-3 was strongly detected in the GC of antral follicles. An in vitro assay revealed that BMP-6 or BMP-7 induced GDF-3 mRNA in GC. Also, GDF-3 increased LH receptor mRNA expression and inhibited the effect of BMP-7, which suppressed the LH receptor mRNA expression in GC. GDF-3, induced with BMP-6 and BMP-7, might play a role in folliculogenesis by inhibiting the effect of BMP cytokines. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  2. Bone Morphogenetic Protein 15 in the Pro-Mature Complex Form Enhances Bovine Oocyte Developmental Competence

    PubMed Central

    Sudiman, Jaqueline; Sutton-McDowall, Melanie L.; Ritter, Lesley J.; White, Melissa A.; Mottershead, David G.; Thompson, Jeremy G.; Gilchrist, Robert B.

    2014-01-01

    Developmental competence of in vitro matured (IVM) oocytes needs to be improved and this can potentially be achieved by adding recombinant bone morphogenetic protein 15 (BMP15) or growth differentiation factor (GDF9) to IVM. The aim of this study was to determine the effect of a purified pro-mature complex form of recombinant human BMP15 versus the commercially available bioactive forms of BMP15 and GDF9 (both isolated mature regions) during IVM on bovine embryo development and metabolic activity. Bovine cumulus oocyte complexes (COCs) were matured in vitro in control medium or treated with 100 ng/ml pro-mature BMP15, mature BMP15 or mature GDF9 +/− FSH. Metabolic measures of glucose uptake and lactate production from COCs and autofluorescence of NAD(P)H, FAD and GSH were measured in oocytes after IVM. Following in vitro fertilisation and embryo culture, day 8 blastocysts were stained for cell numbers. COCs matured in medium +/− FSH containing pro-mature BMP15 displayed significantly improved blastocyst development (57.7±3.9%, 43.5±4.2%) compared to controls (43.3±2.4%, 28.9±3.7%) and to mature GDF9+FSH (36.1±3.0%). The mature form of BMP15 produced intermediate levels of blastocyst development; not significantly different to control or pro-mature BMP15 levels. Pro-mature BMP15 increased intra-oocyte NAD(P)H, and reduced glutathione (GSH) levels were increased by both forms of BMP15 in the absence of FSH. Exogenous BMP15 in its pro-mature form during IVM provides a functional source of oocyte-secreted factors to improve bovine blastocyst development. This form of BMP15 may prove useful for improving cattle and human artificial reproductive technologies. PMID:25058588

  3. Bone morphogenetic protein 15 in the pro-mature complex form enhances bovine oocyte developmental competence.

    PubMed

    Sudiman, Jaqueline; Sutton-McDowall, Melanie L; Ritter, Lesley J; White, Melissa A; Mottershead, David G; Thompson, Jeremy G; Gilchrist, Robert B

    2014-01-01

    Developmental competence of in vitro matured (IVM) oocytes needs to be improved and this can potentially be achieved by adding recombinant bone morphogenetic protein 15 (BMP15) or growth differentiation factor (GDF9) to IVM. The aim of this study was to determine the effect of a purified pro-mature complex form of recombinant human BMP15 versus the commercially available bioactive forms of BMP15 and GDF9 (both isolated mature regions) during IVM on bovine embryo development and metabolic activity. Bovine cumulus oocyte complexes (COCs) were matured in vitro in control medium or treated with 100 ng/ml pro-mature BMP15, mature BMP15 or mature GDF9 +/- FSH. Metabolic measures of glucose uptake and lactate production from COCs and autofluorescence of NAD(P)H, FAD and GSH were measured in oocytes after IVM. Following in vitro fertilisation and embryo culture, day 8 blastocysts were stained for cell numbers. COCs matured in medium +/- FSH containing pro-mature BMP15 displayed significantly improved blastocyst development (57.7±3.9%, 43.5±4.2%) compared to controls (43.3±2.4%, 28.9±3.7%) and to mature GDF9+FSH (36.1±3.0%). The mature form of BMP15 produced intermediate levels of blastocyst development; not significantly different to control or pro-mature BMP15 levels. Pro-mature BMP15 increased intra-oocyte NAD(P)H, and reduced glutathione (GSH) levels were increased by both forms of BMP15 in the absence of FSH. Exogenous BMP15 in its pro-mature form during IVM provides a functional source of oocyte-secreted factors to improve bovine blastocyst development. This form of BMP15 may prove useful for improving cattle and human artificial reproductive technologies.

  4. Union Rate and Complications in Spine Fusion with Recombinant Human Bone Morphogenetic Protein-7: Systematic Review and Meta-Analysis.

    PubMed

    Vavken, Julia; Vavken, Patrick; Mameghani, Alexander; Schaeren, Stefan

    2016-03-01

    Study Design Systematic review and meta-analysis. Objective The objective of this meta-analysis was to evaluate the current best evidence to assess effectiveness and safety of recombinant human bone morphogenetic protein-7 (rhBMP-7) as a biological stimulant in spine fusion. Methods Studies were included if they reported on outcomes after spine fusion with rhBMP-7. The data was synthesized using Mantel-Haenszel pooled risk ratios (RRs) with 95% confidence intervals (CIs). Main end points were union rate, overall complications, postoperative back and leg pain, revision rates, and new-onset cancer. Results Our search produced 796 studies, 6 of which were eligible for inclusion. These studies report on a total of 442 patients (328 experimental, 114 controls) with a mean age of 59 ± 11 years. Our analysis showed no statistically significant differences in union rates (RR 0.97, 95% CI 0.84 to 1.11, p = 0.247), overall complications (RR 0.92, 95% CI 0.71 to 1.20, p = 0.545), postoperative back and leg pain (RR 1.03, 95% CI 0.48 to 2.19, p = 0.941), or revision rate (RR 0.81, 95% CI 0.47 to 1.40, p = 0.449). There was a mathematical indicator of increased tumor rates, but with only one case, the clinical meaningfulness of this finding is questionable. Conclusion We were not able to find data in support of the use of rhBMP-7 for spine fusion. We found no evidence for increased complication or revision rates with rhBMP-7. On the other hand, we also found no evidence in support of improved union rates.

  5. A comparative study of the bone metabolic response to dried plum supplementation and PTH treatment in adult, osteopenic ovariectomized rat.

    PubMed

    Smith, Brenda J; Bu, So Young; Wang, Yan; Rendina, Elizabeth; Lim, Yin F; Marlow, Denver; Clarke, Stephen L; Cullen, Diane M; Lucas, Edralin A

    2014-01-01

    Dried plum has been reported to have potent effects on bone in osteopenic animal models, but the mechanisms through which bone metabolism is altered in vivo remain unclear. To address this issue, a study comparing the metabolic response of dried plum to the anabolic agent, parathyroid hormone (PTH), was undertaken. Six month-old female Sprague Dawley rats (n=84) were sham-operated (SHAM) or ovariectomized (OVX) and maintained on a control diet for 6wks until osteopenia was confirmed. Treatments were initiated consisting of a control diet (AIN-93M) supplemented with dried plum (0, 5, 15 or 25%; w/w) or a positive control group receiving PTH. At the end of 6wks of treatment, whole body and femoral bone mineral density (BMD) were restored by the two higher doses of dried plum to the level of the SHAM group. Trabecular bone volume and cortical thickness were also improved with these two doses of dried plum. Dried plum suppressed the OVX-induced increase in bone turnover as indicated by systemic biomarkers of bone metabolism, N-terminal procollagen type 1 (P1NP) and deoxypyridinoline (DPD). Dynamic bone histomorphometric analysis of the tibial metaphysis revealed that dried plum restored the OVX-induced increase in cancellous bone formation rate (BFR) and mineralizing surface (MS/BS) to the SHAM group, but some doses of dried plum increased endocortical mineral apposition rate (MAR). As expected, PTH significantly increased endocortical MAR and BFR, periosteal BFR, and trabecular MAR and BFR beyond that of the OVX and maintained the accelerated rate of bone resorption associated with OVX. Dried plum up-regulated bone morphogenetic protein 4 (Bmp4) and insulin-like growth factor 1 (Igf1) while down-regulating nuclear factor T cell activator 1 (Nfatc1). These findings demonstrate that in the adult osteopenic OVX animal, the effects of dried plum differ from that of PTH in that dried plum primarily suppressed bone turnover with the exception of the indices of bone formation at the endocortical surface. © 2013.

  6. Bone regeneration in osteoporosis by delivery BMP-2 and PRGF from tetronic-alginate composite thermogel.

    PubMed

    Segredo-Morales, Elisabet; García-García, Patricia; Reyes, Ricardo; Pérez-Herrero, Edgar; Delgado, Araceli; Évora, Carmen

    2018-05-30

    As the life expectancy of the world population increases, osteoporotic (OP) fracture risk increase. Therefore in the present study a novel injectable thermo-responsive hydrogel loaded with microspheres of 17β-estradiol, microspheres of bone morphogenetic protein-2 (BMP-2) and plasma rich in growth factors (PRGF) was applied locally to regenerate a calvaria critical bone defect in OP female rats. Three systems were characterized: Tetronic® 1307 (T-1307) reinforced with alginate (T-A), T-A with PRGF and T-A-PRGF with microspheres. The addition of the microspheres increased the viscosity but the temperature for the maximum viscosity did not change (22-24 °C). The drugs were released during 6 weeks in one fast phase (three days) followed by a long slow phase. In vivo evaluation was made in non-OP and OP rats treated with T-A, T-A with microspheres of 17β-estradiol (T-A-βE), T-A-βE prepared with PRGF (T-A-PRGF-βE), T-A-βE with microspheres of BMP-2 (T-A-βE-BMP-2) and the combination of the three (T-A-PRGF-βE-BMP). After 12 weeks, histological and histomorphometric analyzes showed a synergic effect due to the addition of BMP-2 to the T-A-βE formulation. The PRGF did not increased the bone repair. The new bone filling the OP defect was less mineralized than in the non-OP groups. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. A reciprocal regulatory interaction between megakaryocytes, bone cells, and hematopoietic stem cells.

    PubMed

    Kacena, Melissa A; Gundberg, Caren M; Horowitz, Mark C

    2006-11-01

    A growing body of evidence suggests that megakaryocytes (MK) or their growth factors play a role in skeletal homeostasis. MK have been shown to express and/or secrete several bone-related proteins including osteocalcin, osteonectin, bone sialoprotein, osteopontin, bone morphogenetic proteins, and osteoprotegerin. In addition, at least 3 mouse models have been described in which MK number was significantly elevated with an accompanying marked increase in bone mineral density. Mice overexpressing thrombopoietin, the major MK growth factor, have an osteosclerotic bone phenotype. Mice deficient in transcription factors GATA-1 and NF-E2, which are required for the differentiation of MK, exhibited a strikingly increased bone mass. Importantly, recent studies have demonstrated that MK can stimulate osteoblast (OB) proliferation and differentiation in vitro and that they can also inhibit osteoclast (OC) formation in vitro. These findings suggest that MK play a dual role in skeletal homeostasis by stimulating formation while simultaneously inhibiting resorption. Conversely, cells of the osteoblast lineage support hematopoiesis, including megakaryopoiesis. Postnatal hematopoiesis occurs almost solely in the bone marrow (BM), close to or on endosteal surfaces. This finding, in conjunction with the observed contact of OB with hematopoietic cells, has lead investigators to explore the molecular and cellular interactions between hematopoietic cells and cells of the OB lineage. Importantly, it has been shown that many of the cytokines that are critical for normal hematopoiesis and megakaryopoiesis are produced by OB. Indeed, culturing osteoblasts with CD34+ BM cells significantly enhances hematopoietic cell number by both enhancing the proliferation of long-term culture initiating cells and the proliferation and differentiation of MK. These data are consistent with cells in the OB lineage playing a critical role in the hematopoietic niche. Overall, these observations demonstrate the importance of MK-bone cell interactions in both skeletal homeostasis and hematopoiesis.

  8. Loss of BMP signaling through BMPR1A in osteoblasts leads to greater collagen cross-link maturation and material-level mechanical properties in mouse femoral trabecular compartments

    PubMed Central

    Zhang, Yanshuai; McNerny, Erin Gatenby; Terajima, Masahiko; Raghavan, Mekhala; Romanowicz, Genevieve; Zhang, Zhanpeng; Zhang, Honghao; Kamiya, Nobuhiro; Tantillo, Margaret; Zhu, Peizhi; Scott, Gregory J.; Ray, Manas K.; Lynch, Michelle; Ma, Peter X.; Morris, Michael D.; Yamauchi, Mitsuo; Kohn, David H.; Mishina, Yuji

    2016-01-01

    Bone morphogenetic protein (BMP) signaling pathways play critical roles in skeletal development and new bone formation. Our previous study, however, showed a negative impact of BMP signaling on bone mass because of the osteoblast-specific loss of a BMP receptor (i.e. BMPR1A) showing increased trabecular bone volume and mineral density in mice. Here, we investigated the bone quality and biomechanical properties of the higher bone mass associated with BMPR1A deficiency using the osteoblast-specific Bmpr1a conditional knockout (cKO) mouse model. Collagen biochemical analysis revealed greater levels of the mature cross-link pyridinoline in the cKO bones, in parallel with upregulation of collagen modifying enzymes. Raman spectroscopy distinguished increases in the mature to immature cross-link ratio and mineral to matrix ratio in the trabecular compartments of cKO femora, but not in the cortical compartments. The mineral crystallinity was unchanged in the cKO in either the trabecular or cortical compartments. Further, we tested the intrinsic material properties by nanoindentation and found significantly higher hardness and elastic modulus in the cKO trabecular compartments, but not in the cortical compartments. Four point bending tests of cortical compartments showed lower structural biomechanical properties (i.e. strength and stiffness) in the cKO bones due to the smaller cortical areas. However, there were no significant differences in biomechanical performance at the material level, which was consistent with the nanoindentation test results on the cortical compartment. These studies emphasize the pivotal role of BMPR1A in the determination of bone quality and mechanical integrity under physiological conditions, with different impact on femoral cortical and trabecular compartments. PMID:27113526

  9. Icaritin, a novel plant-derived osteoinductive agent, enhances the osteogenic differentiation of human bone marrow- and human adipose tissue-derived mesenchymal stem cells.

    PubMed

    Wu, Tao; Shu, Tao; Kang, Le; Wu, Jinhui; Xing, Jianzhou; Lu, Zhiqin; Chen, Shuxiang; Lv, Jun

    2017-04-01

    For the treatment of diseases affecting bones using bone regenerative medicine, there is an urgent need to develop safe, inexpensive drugs that can strongly induce bone formation. In the present study, we systematically investigated the effects of icaritin, a metabolic product of icariin, on the osteogenic differentiation of human bone marrow‑derived mesenchymal stem cells (hBMSCs) and human adipose tissue‑derived stem cells (hADSCs) in vitro. After treatment with icaritin at concentrations of 10‑8-10‑5 M, hBMSCs and hADSCs were examined for alkaline phosphatase activity, osteocalcin (OC) secretion, matrix mineralization and expression levels of bone‑related mRNA and proteins. Data showed that icaritin at concentrations 10‑7-10‑5 M significantly increased alkaline phosphatase activity, OC secretion at different time points, and calcium deposition at day 21. In addition, icaritin upregulated the mRNA expression of genes for bone morphogenetic proteins (BMP‑2, ‑4 and ‑7), bone transcription factors (Runx2 and Dlx5) and bone matrix proteins (ALP, OC and Col‑1). Moreover, icaritin increased the protein levels of BMPs, Runx2 and OC, as detected by western blot analysis. These findings suggest that icaritin enhances the osteogenic differentiation of hBMSCS and hADSCs. Icaritin exerts its potent osteogenic effect possibly by directly stimulating the production of BMPs. Although the osteogenic activity of icaritin in vitro was inferior to that of rhBMP‑2, icaritin displayed better results than icariin. Moreover, the low cost, simple extraction procedure, and an abundance of icaritin make it appealing as a bone regenerative medicine.

  10. Periodontal tissue regeneration by combined applications of recombinant human osteogenic protein-1 and bone morphogenetic protein-2. A pilot study in Chacma baboons (Papio ursinus).

    PubMed

    Ripamonti, U; Crooks, J; Petit, J C; Rueger, D C

    2001-08-01

    Native and recombinant human bone morphogenetic/osteogenic proteins (BMPs/ OPs) singly initiate bone induction in vivo. The finding of synchronous but spatially different BMPs/OPs expression during periodontal tissue morphogenesis suggests novel therapeutic approaches using morphogen combinations based on recapitulation of embryonic development. Twelve furcation defects prepared in the first and second mandibular molars of three adult baboons (Papio ursinus) were used to assess whether qualitative histological aspects of periodontal tissue regeneration could be enhanced and tissue morphogenesis modified by combined or single applications of recombinant hOP-1 and hBMP-2. Doses of BMPs/OPs were 100 microg of each protein per 1 g of insoluble collagenous bone matrix as carrier. Approximately 200 mg of carrier matrix was used per furcation defect. Undecalcified sections cut for histological analysis 60 d after healing of hOP-1-treated specimens showed substantial cementogenesis with scattered remnants of the collagenous carrier. hBMP-2 applied alone induced greater amounts of mineralized bone and osteoid when compared to hOP-1 alone or to combined morphogen applications. Combined applications of hOP-1 and hBMP-2 did not enhance alveolar bone regeneration or new attachment formation over and above the single applications of the morphogens. The results of this study, which is the first to attempt to address the structure-activity relationship amongst BMP/OP family members, indicate that tissue morphogenesis induced by hOP-1 and hBMP-2 is qualitatively different when the morphogens are applied singly, with hOP-1 inducing substantial cementogenesis. hBMP-2 treated defects, on the other hand, showed limited cementum formation but a temporal enhancement of alveolar bone regeneration and remodelling. The demonstration of therapeutic mosaicism in periodontal regeneration will require extensive testing of ratios and doses of recombinant morphogen combinations for optimal tissue engineering in clinical contexts.

  11. Synthetic scaffold coating with adeno-associated virus encoding BMP2 to promote endogenous bone repair.

    PubMed

    Dupont, Kenneth M; Boerckel, Joel D; Stevens, Hazel Y; Diab, Tamim; Kolambkar, Yash M; Takahata, Masahiko; Schwarz, Edward M; Guldberg, Robert E

    2012-03-01

    Biomaterial scaffolds functionalized to stimulate endogenous repair mechanisms via the incorporation of osteogenic cues offer a potential alternative to bone grafting for the treatment of large bone defects. We first quantified the ability of a self-complementary adeno-associated viral vector encoding bone morphogenetic protein 2 (scAAV2.5-BMP2) to enhance human stem cell osteogenic differentiation in vitro. In two-dimensional culture, scAAV2.5-BMP2-transduced human mesenchymal stem cells (hMSCs) displayed significant increases in BMP2 production and alkaline phosphatase activity compared with controls. hMSCs and human amniotic-fluid-derived stem cells (hAFS cells) seeded on scAAV2.5-BMP2-coated three-dimensional porous polymer Poly(ε-caprolactone) (PCL) scaffolds also displayed significant increases in BMP2 production compared with controls during 12 weeks of culture, although only hMSC-seeded scaffolds displayed significantly increased mineral formation. PCL scaffolds coated with scAAV2.5-BMP2 were implanted into critically sized immunocompromised rat femoral defects, both with or without pre-seeding of hMSCs, representing ex vivo and in vivo gene therapy treatments, respectively. After 12 weeks, defects treated with acellular scAAV2.5-BMP2-coated scaffolds displayed increased bony bridging and had significantly higher bone ingrowth and mechanical properties compared with controls, whereas defects treated with scAAV2.5-BMP2 scaffolds pre-seeded with hMSCs failed to display significant differences relative to controls. When pooled, defect treatment with scAAV2.5-BMP2-coated scaffolds, both with or without inclusion of pre-seeded hMSCs, led to significant increases in defect mineral formation at all time points and increased mechanical properties compared with controls. This study thus presents a novel acellular bone-graft-free endogenous repair therapy for orthotopic tissue-engineered bone regeneration.

  12. Implant Composed of Demineralized Bone and Mesenchymal Stem Cells Genetically Modified with AdBMP2/AdBMP7 for the Regeneration of Bone Fractures in Ovis aries.

    PubMed

    Hernandez-Hurtado, Adelina A; Borrego-Soto, Gissela; Marino-Martinez, Ivan A; Lara-Arias, Jorge; Romero-Diaz, Viktor J; Abrego-Guerra, Adalberto; Vilchez-Cavazos, Jose F; Elizondo-Riojas, Guillermo; Martinez-Rodriguez, Herminia G; Espinoza-Juarez, Marcela A; Lopez-Romero, Gloria C; Robles-Zamora, Alejandro; Mendoza Lemus, Oscar F; Ortiz-Lopez, Rocio; Rojas-Martinez, Augusto

    2016-01-01

    Adipose-derived mesenchymal stem cells (ADMSCs) are inducible to an osteogenic phenotype by the bone morphogenetic proteins (BMPs). This facilitates the generation of implants for bone tissue regeneration. This study evaluated the in vitro osteogenic differentiation of ADMSCs transduced individually and in combination with adenoviral vectors expressing BMP2 and BMP7. Moreover, the effectiveness of the implant containing ADMSCs transduced with the adenoviral vectors AdBMP2/AdBMP7 and embedded in demineralized bone matrix (DBM) was tested in a model of tibial fracture in sheep. This graft was compared to ewes implanted with untransduced ADMSCs embedded in the same matrix and with injured but untreated animals. In vivo results showed accelerated osteogenesis in the group treated with the AdBMP2/AdBMP7 transduced ADMSC graft, which also showed improved restoration of the normal bone morphology.

  13. Value of Osteoblast-Derived Exosomes in Bone Diseases.

    PubMed

    Ge, Min; Wu, Yingzhi; Ke, Ronghu; Cai, Tianyi; Yang, Junyi; Mu, Xiongzheng

    2017-06-01

    The authors' purpose is to reveal the value of osteoblast-derived exosomes in bone diseases. Microvesicles from supernatants of mouse Mc3t3 were isolated by ultracentrifugation and then the authors presented the protein profile by proteomics analysis. The authors detected a total number of 1536 proteins by mass spectrometry and found 172 proteins overlap with bone database. The Ingenuity Pathway Analysis shows network of "Skeletal and Muscular System Development and Function, Developmental Disorder, Hereditary Disorder" and pathway about osteogenesis. EFNB1 and transforming growth factor beta receptor 3 in the network, LRP6, bone morphogenetic protein receptor type-1, and SMURF1 in the pathway seemed to be valuable in the exosome research of related bone disease. The authors' study unveiled the content of osteoblast-derived exosome and discussed valuable protein in it which might provide novel prospective in bone diseases research.

  14. Bone-Derived Growth Factors

    PubMed Central

    Capanna, R.; Campanacci, D.A.; De Biase, P.; Cuomo, P.; Lorenzoni, A.

    2010-01-01

    Bone regeneration is based on the synergy between osteconduction, osteoinduction and osteogenesis. In recent years, we have witnessed the birth and development of numerous osteoconductive substrates, created with the intention of replacing bone grafts, both autologous and homologous. Recently, attention has shifted to osteogenesis, in other words, to the study of mesenchymal cells and their differentiation into osteoblastic cell lines that can be cultured in vitro (as already seen with chondroblasts). Osteoinduction, too, has been shown to be equally important, ever since Urist’s 1967 study which drew attention to the demineralised bone matrix and its properties. The following twenty years led to the definition of bone morphogenetic protein (BMP) and finally to the marketing of the first ostegenic protein (OP-1) obtained by means of the gene recombination technique. The BMPs produced using this technique that, so far, have been shown to be most active are BMP-2 (Infuse) and BMP-7 (Osigraft). The BMPs are not the only molecules with osteoinductive capacity. Other molecules capable of influencing bone regeneration are: platelet-derived growth factors (PDGFs), the transforming growth factor-beta (TGF-β) family, insulin-like growth factor (IGF-I) and the acidic and basic fibroblast growth factors (FGFs). All these growth factors act in synergy with the BMPs, modulating their action and exerting an inductive and proliferative action on the cell lines responsible for regenerating the bone matrix. The literature has been literally invaded by studies, both experimental and preclinical, on these proteins (Termaat, 2005), and they have provided ample demonstration that the BMPs are effective in improving healing of fractures, pseudoarthrosis and spinal fusions. Important advantages of BMPs are the complete absence of risk of transmissible disease, given that they are produced using recombination technology; their purity, and thus absence of an immune response (although such a response could be linked to the carrier used to administer them); their efficacy, which derives from the use of a pre-established dose and not from the individual variability that is a specific feature of demineralized bone matrix homologous bone grafts. In addition to their use in fractures, pseudoarthrosis and spinal fusions, very recent studies are opening up new possibilities which may represent the future field of application of these proteins: Cook et al. (Cook, 2001, Barrack, 2003) have presented the first results obtained using OP-1 in prosthetic revisions carried out in the presence of bone defects; other authors have published a case report on osteonecrosis of the femoral head treated with grafts in association with OP-1; an Italian group is currently experimenting the use of OP-1 in distraction osteogenesis with the aim of speeding up the results that can be obtained using this already well-established technique. However, the most interesting results on the use of recombinant morphogenetic proteins are those obtained by Warnke et al. (2004), maxillo-facial surgeons who, by mixing synthetic spongious bone grafts, bone marrow concentrate and morphogenetic proteins, prepared a new, replacement mandible for implantation in a patient who had lost his own due to cancer, thereby creating new vacularised bone, tailored to that specific patient. The experimental applications of these new drugs are countless and, with regard to their therapeutic potential, the general feeling is that what we are seeing is only the tip of the iceberg. However, it is necessary to ensure that experiments in this field are always geared towards sustainable clinical applications and, to this end, they should be concentrated in a smaller number of centres and conducted in accordance with approved and recognised guidelines.

  15. BMP-2/PLGA delayed-release microspheres composite graft, selection of bone particulate diameters, and prevention of aseptic inflammation for bone tissue engineering.

    PubMed

    Ji, Ye; Xu, Gong Ping; Zhang, Zhi Peng; Xia, Jing Jun; Yan, Jing Long; Pan, Shang Ha

    2010-03-01

    Autogenous bone grafts are widely used in the repair of bone defects. Growth factors such as bone morphogenetic protein 2 (BMP-2) can induce bone regeneration and enhance bone growth. The combination of an autogenous bone graft and BMP-2 may provide a better osteogenic effect than either treatment alone, but BMP-2 is easily inactivated in body fluid. The objective of this study was to develop a technique that can better preserve the in vivo activity of BMP-2 incorporated in bone grafts. In this study, we first prepared BMP-2/poly(lactic-co-glycolic acid) (PLGA) delayed-release microspheres, and then combined collagen, the delayed-release microspheres, and rat autologous bone particulates to form four groups of composite grafts with different combinations: collagen in group A; collagen combined with bone particulates in group B; collagen combined with BMP-2/PLGA delayed-release microspheres in group C; and collagen combined with both bone particulates and BMP-2/PLGA delayed-release microspheres in group D. The four groups of composite grafts were implanted into the gluteus maximus pockets in rats. The ectopic osteogenesis and ALP level in group D (experimental group) were compared with those in groups A, B, and C (control groups) to study whether it had higher osteogenic capability. Results showed that the composite graft design increased the utility of BMP-2 and reduced the required dose of BMP-2 and volume of autologous bone. The selection of bone particulate diameter had an impact on the osteogenetic potential of bone grafts. Collagen prevented the occurrence of aseptic inflammation and improved the osteoinductivity of BMP-2. These results showed that this composite graft design is effective and feasible for use in bone repair.

  16. Modulation of Stromal Cell-Derived Factor-1/CXC Chemokine Receptor 4 Axis Enhances rhBMP-2-Induced Ectopic Bone Formation

    PubMed Central

    Wise, Joel K.; Sumner, Dale Rick

    2012-01-01

    Enhancement of in vivo mobilization and homing of endogenous mesenchymal stem cells (MSCs) to an injury site is an innovative strategy for improvement of bone tissue engineering and repair. The present study was designed to determine whether mobilization by AMD3100 and/or local homing by delivery of stromal cell-derived factor-1 (SDF-1) enhances recombinant human bone morphogenetic protein-2 (rhBMP-2) induced ectopic bone formation in an established rat model. Rats received an injection of either saline or AMD3100 treatment 1 h before harvesting of bone marrow for in vitro colony-forming unit-fibroblasts (CFU-F) culture or the in vivo subcutaneous implantation of absorbable collagen sponges (ACSs) loaded with saline, recombinant human bone morphogenetic protein-2 (rhBMP-2), SDF-1, or the combination of SDF-1 and rhBMP-2. AMD3100 treatment resulted in a significant decrease in CFU-F number, compared with saline, which confirmed that a single systemic AMD3100 treatment rapidly mobilized MSCs from the bone marrow. At 28 and 56 days, bone formation in the explanted ACS was assessed by microcomputed tomography (μCT) and histology. At 28 days, AMD3100 and/or SDF-1 had no statistically significant effect on bone volume (BV) or bone mineral content (BMC), but histology revealed more active bone formation with treatment of AMD3100, loading of SDF-1, or the combination of both AMD3100 and SDF-1, compared with saline-treated rhBMP-2 loaded ACS. At 56 days, the addition of AMD3100 treatment, loading of SDF-1, or the combination of both resulted in a statistically significant stimulatory effect on BV and BMC, compared with the saline-treated rhBMP-2 loaded ACS. Histology of the 56-day ACS were consistent with the μCT analysis, exhibiting more mature and mineralized bone formation with AMD3100 treatment, SDF-1 loading, or the combination of both, compared with the saline-treated rhBMP-2 loaded ACS. The present study is the first that provides evidence of the efficacy of AMD3100 and SDF-1 treatment to stimulate trafficking of MSCs to an ectopic implant site, in order to ultimately enhance rhBMP-2 induced long-term bone formation. PMID:22035136

  17. Ethanol extract of Peperomia pellucida (Piperaceae) promotes fracture healing by an anabolic effect on osteoblasts.

    PubMed

    Ngueguim, Florence Tsofack; Khan, Mohd Parvez; Donfack, Jean Hubert; Tewari, Deepshikha; Dimo, Theophile; Kamtchouing, Pierre; Maurya, Rakesh; Chattopadhyay, Naibedya

    2013-06-21

    The whole plant or some part of Peperomia pellucida (L.) HBK is used in some parts of Cameroon as a treatment for fracture healing. To evaluate the effect of ethanolic extracts of Peperomia pellucida (L.), a Cameroonian medicinal plant on bone regeneration following bone and marrow injury, and determine the mode of action. Ethanol extract of Peperomia pellucida was administered at 100 and 200mg/kg doses orally to adult female Sprague-Dawley rats having a drill hole injury (0.8mm) in the femur diaphysis. Vehicle (gum-acacia in distilled water) was given to the control group. After 12 days of treatment, animals were euthanized and femur bones collected. Confocal microscopy of calcein labeling at the drill hole site was performed to evaluate bone regeneration. 3-D microarchitecture of drill hole site was analyzed by micorocomputed tomography. Osteogenic effects of the extract were evaluated by assessing mineralized nodule formation of bone marrow stromal cells and expression of osteogenic genes (mRNA level of type-1 collagen, bone morphogenetic protein-2 and osteocalcin genes) in the femur. Ethanol extract from Peperomia Pellucida (L.) dose-dependently induced bone regeneration at the fracture site. At 200mg/kg dose, the extract significantly increased mineral deposition compared to controls. The extract also improved microarchitecture of the regenerating bone evident from increased bone volume fraction, trabecular thickness, trabecular number, and decreased trabecular separation and structure model index. In addition, the extract increased the formation of mineralized nodules from the bone marrow stromal cells. Furthermore, the extract induced the expression of osteogenic genes in the femur including type 1 collagen, osteocalcin and BMP-2, compared to control. Ethanolic extract of P. pellucid (L.) accelerates fracture repair in rats via stimulatory effects on osteoblast differentiation and mineralization, thereby justifying its traditional use. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  18. Stromal derived factor-1 regulates bone morphogenetic protein 2-induced osteogenic differentiation of primary mesenchymal stem cells

    PubMed Central

    Hosogane, Naobumi; Huang, Zhiping; Rawlins, Bernard A.; Liu, Xia; Boachie-Adjei, Oheneba; Boskey, Adele L.; Zhu, Wei

    2010-01-01

    Stromal derived factor-1 (SDF-1) is a chemokine signaling molecule that binds to its transmembrane receptor CXC chemokine receptor-4 (CXCR4). While we previously detected that SDF-1 was co-required with bone morphogenetic protein 2 (BMP2) for differentiating mesenchymal C2C12 cells into osteoblastic cells, it is unknown whether SDF-1 is similarly involved in the osteogenic differentiation of mesenchymal stem cells (MSCs). Therefore, here we examined the role of SDF-1 signaling during BMP2-induced osteogenic differentiation of primary MSCs that were derived from human and mouse bone marrow. Our data showed that blocking of the SDF-1/CXCR4 signal axis or adding SDF-1 protein to MSCs significantly affected BMP2-induced alkaline phosphatase (ALP) activity and osteocalcin (OCN) synthesis, markers of preosteoblasts and mature osteoblasts, respectively. Moreover, disrupting the SDF-1 signaling impaired bone nodule mineralization during terminal differentiation of MSCs. Furthermore, we detected that blocking of the SDF-1 signaling inhibited the BMP2-induced early expression of Runt-related factor-2 (Runx2) and osterix (Osx), two “master” regulators of osteogenesis, and the SDF-1 effect was mediated via intracellular Smad and Erk activation. In conclusion, our results demonstrated a regulatory role of SDF-1 in BMP2-induced osteogenic differentiation of MSCs, as perturbing the SDF-1 signaling affected the differentiation of MSCs towards osteoblastic cells in response to BMP2 stimulation. These data provide novel insights into molecular mechanisms underlying MSC osteogenesis, and will contribute to the development of MSC therapies for enhancing bone formation and regeneration in broad orthopaedic situations. PMID:20362069

  19. Recombinant human bone morphogenetic protein-2 use in the off-label treatment of nonunions and acute fractures: a retrospective review.

    PubMed

    Starman, James S; Bosse, Michael J; Cates, Casey A; Norton, H James

    2012-03-01

    Recombinant human bone morphogenetic protein-2 (BMP-2) is Food and Drug Administration-approved for use in acute open tibial shaft fractures. Some surgeons, however, also use BMP-2 in an "off-label" application for other acute fractures and for nonunion care. This retrospective study was performed to assess radiographic outcomes of off-label uses of BMP-2 for acute fractures and nonunions at our institution. All eligible off-label BMP-2 applications between 2004 and 2008 for acute fractures or nonunions were reviewed. Univariate and multivariate analyses were completed to identify patient and clinical factors that could predict radiographic success or failure of the procedure. One hundred sixteen of 145 BMP-2 applications in 104 of 128 patients met inclusion and exclusion criteria. The overall radiographic union rate was 66% (76 of 116). In the univariate analysis, five factors correlated with significantly higher union rate: volume of bone defect <4 cm3, >2 cortices in contact at the index procedure, male gender, body mass index <30, and history of closed fracture pattern. Within the multivariate analysis, factors independently predictive of radiographic union included open versus closed fracture, gender, and volume of bone defect. Off-label use of BMP-2 in acute fractures and nonunions resulted in a 66% success rate. It remains uncertain whether there is any clinical advantage to this approach, but it appears that female gender, open injury, and higher volumes of bone defect may be important negative prognostic factors for obtaining radiographic union. Appropriately powered prospective randomized trials are needed for further clarification, especially in light of the high cost of this treatment.

  20. Custom-made composite scaffolds for segmental defect repair in long bones.

    PubMed

    Reichert, Johannes C; Wullschleger, Martin E; Cipitria, Amaia; Lienau, Jasmin; Cheng, Tan K; Schütz, Michael A; Duda, Georg N; Nöth, Ulrich; Eulert, Jochen; Hutmacher, Dietmar W

    2011-08-01

    Current approaches for segmental bone defect reconstruction are restricted to autografts and allografts which possess osteoconductive, osteoinductive and osteogenic properties, but face significant disadvantages. The objective of this study was to compare the regenerative potential of scaffolds with different material composition but similar mechanical properties to autologous bone graft from the iliac crest in an ovine segmental defect model. After 12 weeks, in vivo specimens were analysed by X-ray imaging, torsion testing, micro-computed tomography and histology to assess amount, strength and structure of the newly formed bone. The highest amounts of bone neoformation with highest torsional moment values were observed in the autograft group and the lowest in the medical grade polycaprolactone and tricalcium phosphate composite group. The study results suggest that scaffolds based on aliphatic polyesters and ceramics, which are considered biologically inactive materials, induce only limited new bone formation but could be an equivalent alternative to autologous bone when combined with a biologically active stimulus such as bone morphogenetic proteins.

  1. Periodontal regeneration using an injectable bone cement combined with BMP-2 or FGF-2.

    PubMed

    Oortgiesen, Daniël A W; Walboomers, X Frank; Bronckers, Antonius L J J; Meijer, Gert J; Jansen, John A

    2014-03-01

    Periodontitis is a frequently diagnosed oral disease characterized by bone resorption and soft tissue loss around teeth. Unfortunately, currently available therapies only slow or arrest progress of the disease. Ideally, treatment of periodontal defects should be focused on complete regeneration of the lost tissues [(bone and periodontal ligament (PDL)]. As a result, this study used intrabony defects to evaluate the regenerative potential of an injectable macroporous calcium phosphate cement (CaP) in combination with bone morphogenetic protein-2 (BMP-2) or fibroblast growth factor-2 (FGF-2). After creating 30 periodontal defects in 15 Wistar rats, three treatment strategies were conducted: application of CaP only, CaP + BMP-2 and CaP + FGF-2. Animals were euthanized after 12 weeks and processed for histology and histomorphometry. Using CaP alone resulted in limited effects on PDL and bone healing. CaP + BMP-2 showed a good response for bone healing; a significant 2.4 fold increase in bone healing score was observed compared to CaP. However, for PDL healing, CaP + BMP-2 treatment showed no difference compared to the CaP group. The best results were observed with the combined treatment of CaP + FGF-2, which showed a significant 3.3 fold increase in PDL healing score compared to CaP + BMP-2 and a significant 2.6 fold increase compared to CaP. For bone healing, CaP +  FGF-2 showed a significant 1.9 fold increase compared to CaP but no significant difference was noted compared to the CaP + BMP-2 group. The combination of a topical application of FGF-2 and an injectable CaP seems to be a promising treatment modality for periodontal regeneration. Copyright © 2012 John Wiley & Sons, Ltd.

  2. Bone Disease in Axial Spondyloarthritis.

    PubMed

    Van Mechelen, Margot; Gulino, Giulia Rossana; de Vlam, Kurt; Lories, Rik

    2018-05-01

    Axial spondyloarthritis is a chronic inflammatory skeletal disorder with an important burden of disease, affecting the spine and sacroiliac joints and typically presenting in young adults. Ankylosing spondylitis, diagnosed by the presence of structural changes to the skeleton, is the prototype of this disease group. Bone disease in axial spondyloarthritis is a complex phenomenon with the coexistence of bone loss and new bone formation, both contributing to the morbidity of the disease, in addition to pain caused by inflammation. The skeletal structural changes respectively lead to increased fracture risk and to permanent disability caused by ankylosis of the sacroiliac joints and the spine. The mechanism of this new bone formation leading to ankylosis is insufficiently known. The process appears to originate from entheses, specialized structures that provide a transition zone in which tendon and ligaments insert into the underlying bone. Growth factor signaling pathways such as bone morphogenetic proteins, Wnts, and Hedgehogs have been identified as molecular drivers of new bone formation, but the relationship between inflammation and activation of these pathways remains debated. Long-standing control of inflammation appears necessary to avoid ankylosis. Recent evidence and concepts suggest an important role for biomechanical factors in both the onset and progression of the disease. With regard to new bone formation, these processes can be understood as ectopic repair responses secondary to inflammation-induced bone loss and instability. In this review, we discuss the clinical implications of the skeletal changes as well as the underlying molecular mechanisms, the relation between inflammation and new bone formation, and the potential role of biomechanical stress.

  3. Molecular dynamics simulations of the adsorption of bone morphogenetic protein-2 on surfaces with medical relevance.

    PubMed

    Utesch, Tillmann; Daminelli, Grazia; Mroginski, Maria Andrea

    2011-11-01

    Bone morphogenetic protein-2 (BMP-2) plays a crucial role in osteoblast differentiation and proliferation. Its effective therapeutic use for ectopic bone and cartilage regeneration depends, among other factors, on the interaction with the carrier at the implant site. In this study, we used classical molecular dynamics (MD) and a hybrid approach of steered molecular dynamics (SMD) combined with MD simulations to investigate the initial stages of the adsorption of BMP-2 when approaching two implant surfaces, hydrophobic graphite and hydrophilic titanium dioxide rutile. Surface adsorption was evaluated for six different orientations of the protein, two end-on and four side-on, in explicit water environment. On graphite, we observed a weak but stable adsorption. Depending on the initial orientation, hydrophobic patches as well as flexible loops of the protein were involved in the interaction with graphite. On the contrary, BMP-2 adsorbed only loosely to hydrophilic titanium dioxide. Despite a favorable interaction energy between protein and the TiO(2) surface, the rapid formation of a two-layer water structure prevented the direct interaction between protein and titanium dioxide. The first water adlayer had a strong repulsive effect on the protein, while the second attracted the protein toward the surface. For both surfaces, hydrophobic graphite and hydrophilic titanium dioxide, denaturation of BMP-2 induced by adsorption was not observed on the nanosecond time scale.

  4. Randomised controlled clinical trial of augmentation of the alveolar ridge using recombinant human bone morphogenetic protein 2 with hydroxyapatite and bovine-derived xenografts: comparison of changes in volume.

    PubMed

    Nam, J W; Khureltogtokh, S; Choi, H M; Lee, A R; Park, Y B; Kim, H J

    2017-10-01

    The aim of this randomised controlled clinical trial was to assess the early efficacy of bone morphogenetic protein-2 with hydroxyapatite granules (BMP-2/hydroxyapatite) on augmentation of the alveolar ridge, by comparing changes in volume with those associated with the use of an inorganic bovine-derived xenograft (BDX). We studied 20 patients who were divided into two groups using a table of random numbers, and BMP-2/hydroxyapatite and BDX were applied accordingly. Computed tomographic (CT) images and panoramic radiographs were obtained immediately after operation and four months later. CT images were reconstructed in three dimensions to measure volumetric changes, and linear measurements were made on panoramic images. The mean (SD) absorption rates for BMP-2/hydroxyapatite and BDX were 13.2 (8.8)% and 13.8 (20.5)%, respectively. While the mean value did not differ significantly between the two materials, the SD was higher in the BDX group than in the BMP-2/hydroxyapatite group. No clinically important complications occurred in either group. We conclude that both BMP-2/hydroxyapatite and BDX were effective in augmenting the alveolar ridge, but BMP-2/hydroxyapatite seemed to be more useful in complicated bone defects. Copyright © 2017 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. Osteoinductive activity of insulin-functionalized cell culture surfaces obtained using diazonium chemistry

    PubMed Central

    Mikulska, Anna; Filipowska, Joanna; Osyczka, Anna M.; Nowakowska, Maria; Szczubiałka, Krzysztof

    2015-01-01

    Polymeric surfaces suitable for cell culture (DR/Pec) were constructed from diazoresin (DR) and pectin (Pec) in a form of ultrathin films using the layer-by-layer (LbL) technique. The surfaces were functionalized with insulin using diazonium chemistry. Such functionalized surfaces were used to culture human mesenchymal stem cells (hMSCs) to assess their suitability for bone tissue engineering and regeneration. The activity of insulin immobilized on the surfaces (DR/Pec/Ins) was compared to that of insulin dissolved in the culture medium. Human MSC grown on insulin-immobilized DR/Pec surfaces displayed increased proliferation and higher osteogenic activity. The latter was determined by means of alkaline phosphatase (ALP) activity, which increases at early stages of osteoblasts differentiation. Insulin dissolved in the culture medium did not stimulate cell proliferation and its osteogenic activity was significantly lower. Addition of recombinant human bone morphogenetic protein 2 (rhBMP-2) to the culture medium further increased ALP activity in hMSCs indicating additive osteogenic action of immobilized insulin and rhBMP-2. PMID:25629028

  6. Effect of rhBMP-2 on tibial plateau fractures in a canine model.

    PubMed

    Schaefer, Susan L; Lu, Yan; Seeherman, Howard; Li, X Jian; Lopez, Mandi J; Markel, Mark D

    2009-04-01

    This study was to determine the efficacy of recombinant human bone morphogenetic protien-2 (rhBMP-2)/calcium phosphate matrix (CPX) paste to accelerate healing in a canine articular fracture model with associated subchondral defect. rhBMP-2/CPX (BMP), CPX alone (CPX) or autogenous bone graft (ABG) was administered to a canine articular tibial plateau osteotomy with a subchondral defect in each of 21 female dogs. The unoperated contralateral limbs served as controls. Ground reaction forces, synovial fluid, radiographic changes, mechanical testing, bone density, and histology of bone and synovium were analyzed at 6 weeks after surgery. Radiographic analysis demonstrated that the BMP and CPX groups showed improved bony healing compared to the ABG group at week 6. Histomorphometric analysis demonstrated that the BMP group had significantly increased trabecular bone volume compared to the CPX and ABG groups. Mechanical testing revealed that the BMP group had significantly greater maximum failure loads than the ABG group. Histological analysis demonstrated that the BMP group had significantly less sub-synovial inflammation than CPX group. This study demonstrated that rhBMP-2/CPX accelerated healing of articular fractures with subchondral defect compared to ABG in most of the parameters evaluated, and had less subsynovial inflammation than the CPX alone in a canine model.

  7. Host cell recruitment patterns by bone morphogenetic protein-2 releasing hyaluronic acid hydrogels in a mouse subcutaneous environment.

    PubMed

    Todeschi, Maria R; El Backly, Rania M; Varghese, Oommen P; Hilborn, Jöns; Cancedda, Ranieri; Mastrogiacomo, Maddalena

    2017-07-01

    This study aimed to identify host cell recruitment patterns in a mouse model in response to rhBMP-2 releasing hyaluronic acid hydrogels and influence of added nano-hydroxyapatite particles on rhBMP-2 release and pattern of bone formation. Implanted gels were retrieved after implantation and cells were enzymatically dissociated for flow cytometric analysis. Percentages of macrophages, progenitor endothelial cells and putative mesenchymal stem cells were measured. Implants were evaluated for BMP-2 release by ELISA and by histology to monitor tissue formation. Hyaluronic acid+BMP-2 gels influenced the inflammatory response in the bone healing microenvironment. Host-derived putative mesenchymal stem cells were major contributors. Addition of hydroxyapatite nanoparticles modified the release pattern of rhBMP-2, resulting in enhanced bone formation.

  8. Osseous regeneration in the rat calvarium using novel delivery systems for recombinant human bone morphogenetic protein-2 (rhBMP-2).

    PubMed

    Kenley, R; Marden, L; Turek, T; Jin, L; Ron, E; Hollinger, J O

    1994-10-01

    In the current investigation, we report osseous regeneration in critical-size rat calvarial defects using recombinant human bone morphogenetic protein-2 (rhBMP-2) and novel delivery systems based on biomaterials. The novel systems combine rhBMP-2 with dry powder microparticles of poly(D,L-lactide-co-glycolide) (PLGA). The mixture of rhBMP-2 with PLGA microparticles is added to an aqueous solution of biopolymer to yield a semisolid paste. The biopolymers tested include autologous blood clot, hydroxypropyl methylcellulose, and sodium alginate cross-linked with calcium ion. Insoluble collageneous bone matrix was also studied as a control. Test articles were made at 0-, 10-, and 30-micrograms doses of rhBMP-2 and imiplanted in 8-mm-diameter rat calvarial defects (which will not heal if left untreated). The animals were examined 21 days after implantation by radiography, radiomorphometry, histology, and histomorphometry. All tested materials containing rhBMP-2 restored radiopacity and normal contouring to the calvarial defects. Samples without added rhBMP-2 yielded only soft tissue within the defects. Histology showed restoration of inner and outer bone tables plus marrow constituents. The PLGA microparticles were significantly resorbed at the 21-day time point. Although small differences between delivery systems were evident at 0- and 10-micrograms rhBMP-2 doses, all test articles performed essentially equivalently at the 30-micrograms dose. Thus, novel delivery systems for rhBMP-2 offer the promise of combining the intrinsic bioactivity of the osteoinductive protein with pharmaceutically acceptable biomaterials.

  9. Deficiency of retinaldehyde dehydrogenase 1 induces BMP2 and increases bone mass in vivo.

    PubMed

    Nallamshetty, Shriram; Wang, Hong; Rhee, Eun-Jung; Kiefer, Florian W; Brown, Jonathan D; Lotinun, Sutada; Le, Phuong; Baron, Roland; Rosen, Clifford J; Plutzky, Jorge

    2013-01-01

    The effects of retinoids, the structural derivatives of vitamin A (retinol), on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA) and its precursor all trans retinaldehyde (Rald), exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1), the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT) demonstrated that Aldh1a1-deficient (Aldh1a1(-/-) ) female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT) mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1(-/-) mice. In serum assays, Aldh1a1(-/-) mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1(-/-) mesenchymal stem cells (MSCs) expressed significantly higher levels of bone morphogenetic protein 2 (BMP2) and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1(-/-) mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1(-/-) mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR)-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling.

  10. Influence of Bone and Muscle Injuries on the Osteogenic Potential of Muscle Progenitors: Contribution of Tissue Environment to Heterotopic Ossification

    PubMed Central

    Molligan, Jeremy; Mitchell, Reed; Schon, Lew; Achilefu, Samuel; Zahoor, Talal; Cho, Young; Loube, Jeffery

    2016-01-01

    By using surgical mouse models, this study investigated how the tissue environment influences the osteogenic potential of muscle progenitors (m-progenitors) and potentially contributes to heterotopic ossification (HO). Injury was induced by clamping the gluteus maximus and medius (group M) or osteotomy of greater trochanter (group O) on the right hip, as well as combined muscle injury and osteotomy of greater trochanter (group M+O). The gluteus maximus and medius of the operated hips were harvested at days 1, 3, 5, and 10 for isolation of m-progenitors. The cells were cultured in an osteogenic medium for 3 weeks, and osteogenesis was evaluated by matrix mineralization and the expression of osteogenesis-related genes. The expression of type I collagen, RUNX2 (runt-related transcription factor 2), and osteocalcin by the m-progenitors of group M+O was significantly increased, compared with groups M and O. Osteogenic m-progenitors in group O increased the expression of bone morphogenetic protein 2 and also bone morphogenetic protein antagonist differential screening-selected gene aberrative in neuroblastoma. On histology, there was calcium deposition mostly in the muscles of group M+O harvested at day 10. CD56, representing myogenic progenitors, was highly expressed in the m-progenitors isolated from group M (day 10), but m-progenitors of group M+O (day 10) exhibited the highest expression of platelet-derived growth factor receptor α (PDGFR-α), a marker of muscle-derived mesenchymal stem cells (M-MSCs). The expressions of PDGFR-α and RUNX2 were colocalized in osteogenic m-progenitors. The data indicate that the tissue environment simulated in the M+O model is a favorable condition for HO formation. Most likely, M-MSCs, rather than myogenic progenitors, in the m-progenitors participate in HO formation. Significance The prevalence of traumatic heterotopic ossification (HO) is high in war injury. The pathogenesis of HO is still unknown. This study clarified the contribution of a tissue environment created by bone or muscle injury to the formation of HO. The study also found that muscle-derived mesenchymal stem cells, but not myogenic progenitors, are involved in the formation of HO. The findings of this study could be used to strategize the prevention and treatment of HO. PMID:27112178

  11. Influence of Bone and Muscle Injuries on the Osteogenic Potential of Muscle Progenitors: Contribution of Tissue Environment to Heterotopic Ossification.

    PubMed

    Molligan, Jeremy; Mitchell, Reed; Schon, Lew; Achilefu, Samuel; Zahoor, Talal; Cho, Young; Loube, Jeffery; Zhang, Zijun

    2016-06-01

    : By using surgical mouse models, this study investigated how the tissue environment influences the osteogenic potential of muscle progenitors (m-progenitors) and potentially contributes to heterotopic ossification (HO). Injury was induced by clamping the gluteus maximus and medius (group M) or osteotomy of greater trochanter (group O) on the right hip, as well as combined muscle injury and osteotomy of greater trochanter (group M+O). The gluteus maximus and medius of the operated hips were harvested at days 1, 3, 5, and 10 for isolation of m-progenitors. The cells were cultured in an osteogenic medium for 3 weeks, and osteogenesis was evaluated by matrix mineralization and the expression of osteogenesis-related genes. The expression of type I collagen, RUNX2 (runt-related transcription factor 2), and osteocalcin by the m-progenitors of group M+O was significantly increased, compared with groups M and O. Osteogenic m-progenitors in group O increased the expression of bone morphogenetic protein 2 and also bone morphogenetic protein antagonist differential screening-selected gene aberrative in neuroblastoma. On histology, there was calcium deposition mostly in the muscles of group M+O harvested at day 10. CD56, representing myogenic progenitors, was highly expressed in the m-progenitors isolated from group M (day 10), but m-progenitors of group M+O (day 10) exhibited the highest expression of platelet-derived growth factor receptor α (PDGFR-α), a marker of muscle-derived mesenchymal stem cells (M-MSCs). The expressions of PDGFR-α and RUNX2 were colocalized in osteogenic m-progenitors. The data indicate that the tissue environment simulated in the M+O model is a favorable condition for HO formation. Most likely, M-MSCs, rather than myogenic progenitors, in the m-progenitors participate in HO formation. The prevalence of traumatic heterotopic ossification (HO) is high in war injury. The pathogenesis of HO is still unknown. This study clarified the contribution of a tissue environment created by bone or muscle injury to the formation of HO. The study also found that muscle-derived mesenchymal stem cells, but not myogenic progenitors, are involved in the formation of HO. The findings of this study could be used to strategize the prevention and treatment of HO. ©AlphaMed Press.

  12. Chemical modification of extracellular matrix by cold atmospheric plasma-generated reactive species affects chondrogenesis and bone formation

    PubMed Central

    Eisenhauer, Peter; Chernets, Natalie; Song, You; Dobrynin, Danil; Pleshko, Nancy; Steinbeck, Marla J.; Freeman, Theresa A.

    2017-01-01

    The goal of this study was to investigate whether cold plasma generated by dielectric barrier discharge (DBD) modifies extracellular matrices (ECM) to influence chondrogenesis and endochondral ossification. Replacement of cartilage by bone during endochondral ossification is essential in fetal skeletal development, bone growth and fracture healing. Regulation of this process by the ECM occurs through matrix remodelling, involving a variety of cell attachment molecules and growth factors, which influence cell morphology and protein expression. The commercially available ECM, Matrigel, was treated with microsecond or nanosecond pulsed (µsp or nsp, respectively) DBD frequencies conditions at the equivalent frequencies (1 kHz) or power (~1 W). Recombinant human bone morphogenetic protein-2 was added and the mixture subcutaneously injected into mice to simulate ectopic endochondral ossification. Two weeks later, the masses were extracted and analysed by microcomputed tomography. A significant increase in bone formation was observed in Matrigel treated with µsp DBD compared with control, while a significant decrease in bone formation was observed for both nsp treatments. Histological and immunohistochemical analysis showed Matrigel treated with µsp plasma increased the number of invading cells, the amount of vascular endothelial growth factor and chondrogenesis while the opposite was true for Matrigel treated with nsp plasma. In support of the in vivo Matrigel study, 10 T1/2 cells cultured in vitro on µsp DBD-treated type I collagen showed increased expression of adhesion proteins and activation of survival pathways, which decreased with nsp plasma treatments. These results indicate DBD modification of ECM can influence cellular behaviours to accelerate or inhibit chondrogenesis and endochondral ossification. PMID:27510797

  13. * Calvarial Bone Regeneration Is Enhanced by Sequential Delivery of FGF-2 and BMP-2 from Layer-by-Layer Coatings with a Biomimetic Calcium Phosphate Barrier Layer.

    PubMed

    Gronowicz, Gloria; Jacobs, Emily; Peng, Tao; Zhu, Li; Hurley, Marja; Kuhn, Liisa T

    2017-12-01

    A drug delivery coating for synthetic bone grafts has been developed to provide sequential delivery of multiple osteoinductive factors to better mimic aspects of the natural regenerative process. The coating is composed of a biomimetic calcium phosphate (bCaP) layer that is applied to a synthetic bone graft and then covered with a poly-l-Lysine/poly-l-Glutamic acid polyelectrolyte multilayer (PEM) film. Bone morphogenetic protein-2 (BMP-2) was applied before the coating process directly on the synthetic bone graft and then, bCaP-PEM was deposited followed by adsorption of fibroblast growth factor-2 (FGF-2) into the PEM layer. Cells access the FGF-2 immediately, while the bCaP-PEM temporally delays the cell access to BMP-2. In vitro studies with cells derived from mouse calvarial bones demonstrated that Sca-1 and CD-166 positive osteoblast progenitor cells proliferated in response to media dosing with FGF-2. Coated scaffolds with BMP-2 and FGF-2 were implanted in mouse calvarial bone defects and harvested at 1 and 3 weeks. After 1 week in vivo, proliferation of cells, including Sca-1+ progenitors, was observed with low dose FGF-2 and BMP-2 compared to BMP-2 alone, indicating that in vivo delivery of FGF-2 activated a similar population of cells as shown by in vitro testing. At 3 weeks, FGF-2 and BMP-2 delivery increased bone formation more than BMP-2 alone, particularly in the center of the defect, confirming that the proliferation of the Sca-1 positive osteoprogenitors by FGF-2 was associated with increased bone healing. Areas of bone mineralization were positive for double fluorochrome labeling of calcium and alkaline phosphatase staining of osteoblasts, along with increased TRAP+ osteoclasts, demonstrating active bone formation distinct from the bone-like collagen/hydroxyapatite scaffold. In conclusion, the addition of a bCaP layer to PEM delayed access to BMP-2 and allowed the FGF-2 stimulated progenitors to populate the scaffold before differentiating in response to BMP-2, leading to improved bone defect healing.

  14. Development of implants composed of bioactive materials for bone repair

    NASA Astrophysics Data System (ADS)

    Xiao, Wei

    The purpose of this Ph.D. research was to address the clinical need for synthetic bioactive materials to heal defects in non-loaded and loaded bone. Hollow hydroxyapatite (HA) microspheres created in a previous study were evaluated as a carrier for controlled release of bone morphogenetic protein-2 (BMP2) in bone regeneration. New bone formation in rat calvarial defects implanted with BMP2-loaded microspheres (43%) was significantly higher than microspheres without BMP2 (17%) at 6 weeks postimplantation. Then hollow HA microspheres with a carbonate-substituted composition were prepared to improve their resorption rate. Hollow HA microspheres with 12 wt. % of carbonate showed significantly higher new bone formation (73 +/- 8%) and lower residual HA (7 +/- 2%) than stoichiometric HA microspheres (59 +/- 2% new bone formation; 21 +/- 3% residual HA). The combination of carbonate-substituted hollow HA microspheres and clinically-safe doses of BMP2 could provide promising implants for healing non-loaded bone defects. Strong porous scaffolds of bioactive silicate (13-93) glass were designed with the aid of finite-element modeling, created by robocasting and evaluated for loaded bone repair. Scaffolds with a porosity gradient to mimic human cortical bone showed a compressive strength of 88 +/- 20 MPa, a flexural strength of 34 +/- 5 MPa and the ability to support bone infiltration in vivo. The addition of a biodegradable polylactic acid (PLA) layer to the external surface of these scaffolds increased their load-bearing capacity in four-point bending by 50% and dramatically enhanced their work of fracture, resulting in a "ductile" mechanical response. These bioactive glass-PLA composites, combining bioactivity, high strength, high work of fracture and an internal architecture conducive to bone infiltration, could provide optimal implants for structural bone repair.

  15. In vivo bone regeneration using a novel porous bioactive composite

    NASA Astrophysics Data System (ADS)

    Xie, En; Hu, Yunyu; Chen, Xiaofeng; Bai, Xuedong; Li, Dan; Ren, Li; Zhang, Ziru

    2008-11-01

    Many commercial bone graft substitutes (BGS) and experimental bone tissue engineering scaffolds have been developed for bone repair and regeneration. This study reports the in vivo bone regeneration using a newly developed porous bioactive and resorbable composite that is composed of bioactive glass (BG), collagen (COL), hyaluronic acid (HYA) and phosphatidylserine (PS), BG-COL-HYA-PS. The composite was prepared by a combination of sol-gel and freeze-drying methods. A rabbit radius defect model was used to evaluate bone regeneration at time points of 2, 4 and 8 weeks. Techniques including radiography, histology, and micro-CT were applied to characterize the new bone formation. 8 weeks results showed that (1) nearly complete bone regeneration was achieved for the BG-COL-HYA-PS composite that was combined with a bovine bone morphogenetic protein (BMP); (2) partial bone regeneration was achieved for the BG-COL-HYA-PS composites alone; and (3) control remained empty. This study demonstrated that the novel BG-COL-HYA-PS, with or without the grafting of BMP incorporation, is a promising BGS or a tissue engineering scaffold for non-load bearing orthopaedic applications.

  16. Phylogenetic, functional, and structural components of variation in bone growth rate of amniotes.

    PubMed

    Cubo, Jorge; Legendre, Pierre; de Ricqlès, Armand; Montes, Laëtitia; de Margerie, Emmanuel; Castanet, Jacques; Desdevises, Yves

    2008-01-01

    The biological features observed in every living organism are the outcome of three sets of factors: historical (inherited by homology), functional (biological adaptation), and structural (properties inherent to the materials with which organs are constructed, and the morphogenetic rules by which they grow). Integrating them should bring satisfactory causal explanations of empirical data. However, little progress has been accomplished in practice toward this goal, because a methodologically efficient tool was lacking. Here we use a new statistical method of variation partitioning to analyze bone growth in amniotes. (1) Historical component. The variation of bone growth rates contains a significant phylogenetic signal, suggesting that the observed patterns are partly the outcome of shared ancestry. (2) Functional causation. High growth rates, although energy costly, may be adaptive (i.e., they may increase survival rates) in taxa showing short growth periods (e.g., birds). In ectothermic amniotes, low resting metabolic rates may limit the maximum possible growth rates. (3) Structural constraint. Whereas soft tissues grow through a multiplicative process, growth of mineralized tissues is accretionary (additive, i.e., mineralization fronts occur only at free surfaces). Bone growth of many amniotes partially circumvents this constraint: it is achieved not only at the external surface of the bone shaft, but also within cavities included in the bone cortex as it grows centrifugally. Our approach contributes to the unification of historicism, functionalism, and structuralism toward a more integrated evolutionary biology.

  17. Elastin-like-polypeptide based fusion proteins for osteogenic factor delivery in bone healing.

    PubMed

    McCarthy, Bryce; Yuan, Yuan; Koria, Piyush

    2016-07-08

    Modern treatments of bone injuries and diseases are becoming increasingly dependent on the usage of growth factors to stimulate bone growth. Bone morphogenetic protein-2 (BMP-2), a potent osteogenic inductive protein, exhibits promising results in treatment models, but recently has had its practical efficacy questioned due to the lack of local retention, ectopic bone formation, and potentially lethal inflammation. Where a new delivery technique of the BMP-2 is necessary, here we demonstrate the viability of an elastin-like peptide (ELP) fusion protein containing BMP-2 for delivery of the BMP-2. This fusion protein retains the performance characteristics of both the BMP-2 and ELP. The fusion protein was found to induce osteogenic differentiation of mesenchymal stem cells as evidenced by the production of alkaline phosphatase and extracellular calcium deposits in response to treatment by the fusion protein. Retention of the ELPs inverse phase transition property has allowed for expression of the fusion protein within a bacterial host (such as Escherichia coli) and easy and rapid purification using inverse transition cycling. The fusion protein formed self-aggregating nanoparticles at human-body temperature. The data collected suggests the viability of these fusion protein nanoparticles as a dosage-efficient and location-precise noncytotoxic delivery vehicle for BMP-2 in bone treatment. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1029-1037, 2016. © 2016 American Institute of Chemical Engineers.

  18. Effects of Roughly Focused Extracorporeal Shock Waves Therapy on the Expressions of Bone Morphogenetic Protein-2 and Osteoprotegerin in Osteoporotic Fracture in Rats

    PubMed Central

    Huang, Hai-Ming; Li, Xiao-Lin; Tu, Shu-Qiang; Chen, Xiao-Feng; Lu, Chang-Chun; Jiang, Liang-Hua

    2016-01-01

    Background: Roughly focused extracorporeal shock waves therapy (ESWT) is characterized by a wide focal area, a large therapy zone, easy positioning, and less pain during treatment. The purpose of this study was to investigate the effects of roughly focused ESWT on the expression of osteoprotegerin (OPG) and bone morphogenetic protein-2 (BMP-2) in osteoporotic fractures in rats. Methods: Seventy-two female Sprague-Dawley (SD) rats, 3 months old, were divided into sham-operated group (n = 6) and an ovariectomized (OVX) group (n = 66). Sixty OVX SD rats were used as a model of double proximal tibial osteotomy and inner fixation. The osteotomy site in the left tibia was treated with roughly focused ESWT once at an energy density of 0.26 mJ/mm2, 60 doses/min, and 2000 pact quantities. The contralateral right tibia was left untreated and served as a control. Expression of OPG and BMP-2 in the callus of the osteoporotic fracture area was assessed using immunohistochemistry, real-time polymerase chain reaction (PCR), and Western blotting analysis. Results: Bone mineral density (BMD) at the proximal tibia, femur, and L5 spine was significantly reduced after ovariectomy. BMD of proximal tibia was 12.9% less in the OVX group than that in the sham-operated group. Meanwhile, bilateral oophorectomy resulted in a lower trabecular bone volume fraction (BV/TV) in the proximal tibia of the sham-OVX animals. Three months after bilateral oophorectomy, BV/TV was 14.29% of baseline BV/TV in OVX legs versus 45.91% in the sham-OVX legs (P < 0.001). These data showed that the SD rats became a suitable model of osteoporosis, 3 months after they were OVX. Immunohistochemical analysis showed higher levels of BMP-2 and OPG expression in the treatment group than those in the control group. Compared with the contralateral controls, decreased expression of OPG and BMP-2 at 3 days after roughly focused ESWT, followed by a later increase at 7 days, was indicated by real-time PCR and Western blotting analysis. The OPG messenger RNA (mRNA) expression levels peaked at 6 weeks after the shock wave treatment, paired with a much earlier (at 4 weeks) increase of BMP-2, and declined close to normal at 8 weeks. Conclusions: Roughly focused ESWT may promote the expression of OPG and BMP-2 in the osteoporotic fracture area in rats. BMP-2 and OPG may act synergistically and may lead to a significant enhancement of bone formation and remodeling. PMID:27779163

  19. Gremlin 1 Identifies a Skeletal Stem Cell with Bone, Cartilage, and Reticular Stromal Potential

    PubMed Central

    Worthley, Daniel L.; Churchill, Michael; Compton, Jocelyn T.; Tailor, Yagnesh; Rao, Meenakshi; Si, Yiling; Levin, Daniel; Schwartz, Matthew G.; Uygur, Aysu; Hayakawa, Yoku; Gross, Stefanie; Renz, Bernhard W.; Setlik, Wanda; Martinez, Ashley N.; Chen, Xiaowei; Nizami, Saqib; Lee, Heon Goo; Kang, H. Paco; Caldwell, Jon-Michael; Asfaha, Samuel; Westphalen, C. Benedikt; Graham, Trevor; Jin, Guangchun; Nagar, Karan; Wang, Hongshan; Kheirbek, Mazen A.; Kolhe, Alka; Carpenter, Jared; Glaire, Mark; Nair, Abhinav; Renders, Simon; Manieri, Nicholas; Muthupalani, Sureshkumar; Fox, James G.; Reichert, Maximilian; Giraud, Andrew S.; Schwabe, Robert F.; Pradere, Jean-Phillipe; Walton, Katherine; Prakash, Ajay; Gumucio, Deborah; Rustgi, Anil K.; Stappenbeck, Thaddeus S.; Friedman, Richard A.; Gershon, Michael D.; Sims, Peter; Grikscheit, Tracy; Lee, Francis Y.; Karsenty, Gerard; Mukherjee, Siddhartha; Wang, Timothy C.

    2014-01-01

    The stem cells that maintain and repair the postnatal skeleton remain undefined. One model suggests that perisinusoidal mesenchymal stem cells (MSCs) give rise to osteoblasts, chondrocytes, marrow stromal cells, and adipocytes, although the existence of these cells has not been proven through fate-mapping experiments. We demonstrate here that expression of the bone morphogenetic protein (BMP) antagonist gremlin 1 defines a population of osteochondroreticular (OCR) stem cells in the bone marrow. OCR stem cells self-renew and generate osteoblasts, chondrocytes, and reticular marrow stromal cells, but not adipocytes. OCR stem cells are concentrated within the metaphysis of long bones not in the perisinusoidal space and are needed for bone development, bone remodeling, and fracture repair. Grem1 expression also identifies intestinal reticular stem cells (iRSCs) that are cells of origin for the periepithelial intestinal mesenchymal sheath. Grem1 expression identifies distinct connective tissue stem cells in both the bone (OCR stem cells) and the intestine (iRSCs). PMID:25594183

  20. Comparative expression analyses of bone morphogenetic protein 4 (BMP4) expressions in muscles of tilapia and common carp indicate that BMP4 plays a role in the intermuscular bone distribution in a dose-dependent manner.

    PubMed

    Su, Shengyan; Dong, Zaijie

    2018-01-01

    Intermuscular bones in fish negatively influence both meet processing and attractiveness to consumers. Tilapia (Oreochromis niloticus) and common carp (Cyprinus carpio) are both major farmed fish species globally, but whereas the former does not possess intermuscular bones, the latter does. Therefore, these two species might present a good model to study the genetic control of distribution of intermuscular bones in fish. Bone morphogenetic protein 4 (BMP4) gene is associated with tissue ossification and bone regeneration in mammals, but in fish its role in ossification remains understudied. To study the relationship between BMP4 and bone distribution in fish, we determined the expression of BMP4 in muscle tissues of common carp and tilapia on transcriptional and translational levels. As the gene has been merely predicted in silico from the genome of common carp, we have cloned and characterized it. The gene (GenBank: HQ446455) contains one intron and two exons, which encode a 400-amino acid protein with high homology to other known BMP4 protein sequences. Phylogenetic analysis showed that common carp clustered within the Cypriniformes clade (zebrafish was the closest ortholog) and tilapia within the Percomorpha clade. Using microCT scanning, we confirmed that intermuscular bones could be observed only in common carp (none in tilapia), but only in dorsal and caudal muscles (none in the ventral muscle). Expression levels of BMP4 in the muscles of common carp were in agreement with this observation both on transcriptional (qPCR) and translational (immunohistochemistry) level: higher in dorsal and caudal muscles, and lower in the ventral muscle. In tilapia, expression of BMP4 gene was also detectable in all three muscles, but expression levels in all three muscles were comparable to the one observed in the ventral muscle of carp, i.e., very low. Therefore, among the six studied muscles, the expression of BMP4 was high only in the two that possess intermuscular bones: dorsal and caudal muscles of common carp. The results of this study suggest that BMP4 is likely to play a key role in the determination of intermuscular bone distribution in fish in a dose-dependent manner. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Bone morphogenetic protein 4 antagonizes hair cell regeneration in the avian auditory epithelium.

    PubMed

    Lewis, Rebecca M; Keller, Jesse J; Wan, Liangcai; Stone, Jennifer S

    2018-07-01

    Permanent hearing loss is often a result of damage to cochlear hair cells, which mammals are unable to regenerate. Non-mammalian vertebrates such as birds replace damaged hair cells and restore hearing function, but mechanisms controlling regeneration are not understood. The secreted protein bone morphogenetic protein 4 (BMP4) regulates inner ear morphogenesis and hair cell development. To investigate mechanisms controlling hair cell regeneration in birds, we examined expression and function of BMP4 in the auditory epithelia (basilar papillae) of chickens of either sex after hair cell destruction by ototoxic antibiotics. In mature basilar papillae, BMP4 mRNA is highly expressed in hair cells, but not in hair cell progenitors (supporting cells). Supporting cells transcribe genes encoding receptors for BMP4 (BMPR1A, BMPR1B, and BMPR2) and effectors of BMP4 signaling (ID transcription factors). Following hair cell destruction, BMP4 transcripts are lost from the sensory epithelium. Using organotypic cultures, we demonstrate that treatments with BMP4 during hair cell destruction prevent supporting cells from upregulating expression of the pro-hair cell transcription factor ATOH1, entering the cell cycle, and fully transdifferentiating into hair cells, but they do not induce cell death. By contrast, noggin, a BMP4 inhibitor, increases numbers of regenerated hair cells. These findings demonstrate that BMP4 antagonizes hair cell regeneration in the chicken basilar papilla, at least in part by preventing accumulation of ATOH1 in hair cell precursors. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Identification of bone morphogenetic protein 9 (BMP9) as a novel profibrotic factor in vitro.

    PubMed

    Muñoz-Félix, José M; Cuesta, Cristina; Perretta-Tejedor, Nuria; Subileau, Mariela; López-Hernández, Francisco J; López-Novoa, José M; Martínez-Salgado, Carlos

    2016-09-01

    Upregulated synthesis of extracellular matrix (ECM) proteins by myofibroblasts is a common phenomenon in the development of fibrosis. Although the role of TGF-β in fibrosis development has been extensively studied, the involvement of other members of this superfamily of cytokines, the bone morphogenetic proteins (BMPs) in organ fibrosis has given contradictory results. BMP9 is the main ligand for activin receptor-like kinase-1 (ALK1) TGF-β1 type I receptor and its effect on fibrosis development is unknown. Our purpose was to study the effect of BMP9 in ECM protein synthesis in fibroblasts, as well as the involved receptors and signaling pathways. In cultured mice fibroblasts, BMP9 induces an increase in collagen, fibronectin and connective tissue growth factor expression, associated with Smad1/5/8, Smad2/3 and Erk1/2 activation. ALK5 inhibition with SB431542 or ALK1/2/3/6 with dorsomorphin-1, inhibition of Smad3 activation with SIS3, and inhibition of the MAPK/Erk1/2 with U0126, demonstrates the involvement of these pathways in BMP9-induced ECM synthesis in MEFs. Whereas BMP9 induced Smad1/5/8 phosphorylation through ALK1, it also induces Smad2/3 phosphorylation through ALK5 but only in the presence of ALK1. Summarizing, this is the first study that accurately identifies BMP9 as a profibrotic factor in fibroblasts that promotes ECM protein expression through ALK1 and ALK5 receptors. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Disruption of the bone morphogenetic protein receptor 2 pathway in nitrofen-induced congenital diaphragmatic hernia.

    PubMed

    Gosemann, Jan-Hendrik; Friedmacher, Florian; Fujiwara, Naho; Alvarez, Luis A J; Corcionivoschi, Nicolae; Puri, Prem

    2013-08-01

    Congenital diaphragmatic hernia (CDH) remains a major therapeutic challenge despite advances in neonatal resuscitation and intensive care. The high mortality and morbidity in CDH has been attributed to pulmonary hypoplasia and persistent pulmonary hypertension (PH). Bone morphogenetic protein receptor 2 (BMPR2) plays a key role in pulmonary vasculogenesis during the late stages of fetal lung development. BMPR2 is essential for control of endothelial and smooth muscle cell proliferation. Dysfunction of BMPR2 and downstream signaling have been shown to disturb the crucial balance of proliferation of smooth muscle cells contributing to the pathogenesis of human and experimental PH. We designed this study to investigate the hypothesis that BMPR2 signaling is disrupted in nitrofen-induced CDH. Pregnant rats were treated with nitrofen or vehicle on gestational day 9 (D9). Fetuses were sacrificed on D21 and divided into CDH and control. Quantitative real-time polymerase chain reaction, Western blotting, and confocal-immunofluorescence were performed to determine pulmonary gene expression levels and protein expression of BMPR2 and related proteins. Pulmonary Bmpr2 gene expression levels were significantly decreased in nitrofen-induced CDH compared to controls. Western blotting and confocal microscopy revealed decreased pulmonary BMPR2 protein expression and increased activation of p38(MAPK) in CDH compared to controls. The observed disruption of the BMPR2 signaling pathway may lead to extensive vascular remodeling and contribute to PH in the nitrofen-induced CDH model. BMPR2 may therefore represent a potential target for the treatment of PH in CDH. © 2013 Wiley Periodicals, Inc.

  4. Novel loci interacting epistatically with Bone Morphogenetic Protein Receptor 2 cause familial pulmonary arterial hypertension

    PubMed Central

    Rodriguez-Murillo, Laura; Subaran, Ryan; Stewart, William C. L.; Pramanik, Sreemanta; Marathe, Sudhir; Barst, Robyn J.; Chung, Wendy K.; Greenberg, David A.

    2009-01-01

    Background Familial pulmonary arterial hypertension (FPAH) is a rare, autosomal-dominant inherited disease with low penetrance. Mutations in the Bone Morphogenetic Protein Receptor 2 (BMPR2) have been identified in at least 70% of FPAH patients. However, the lifetime penetrance of these BMPR2 mutations is 10-20%, suggesting that genetic and/or environmental modifiers are required for disease expression. Our goal in this study is to identify genetic loci that may influence FPAH expression in BMPR2-mutation-carriers. Methods We performed a genome-wide linkage scan in 15 FPAH families segregating for BMPR2 mutations. We used a dense SNP array and a novel multi-scan linkage procedure that provides increased power and precision for the localization of linked loci. Results We observed linkage evidence in four regions: 3q22 (median LOD=3.43), 3p12 (median LOD = 2.35), 2p22 (median LOD = 2.21), and 13q21 (median LOD = 2.09). When used in conjunction with the nonparametric bootstrap, our approach yields high-resolution to identify candidate gene regions containing putative BMPR2-interacting genes. Imputation of the disease model by LOD score maximization indicates that the 3q22 locus alone predicts most FPAH cases in BMPR2-mutation carriers, providing strong evidence that BMPR2 and the 3q22 locus interact epistatically. Conclusions Our findings suggest that genotypes at loci in the newly-identified regions, especially at 3q22, could improve FPAH risk prediction in FPAH families and suggest other targets for therapeutic intervention. PMID:19864167

  5. Novel loci interacting epistatically with bone morphogenetic protein receptor 2 cause familial pulmonary arterial hypertension.

    PubMed

    Rodriguez-Murillo, Laura; Subaran, Ryan; Stewart, William C L; Pramanik, Sreemanta; Marathe, Sudhir; Barst, Robyn J; Chung, Wendy K; Greenberg, David A

    2010-02-01

    Familial pulmonary arterial hypertension (FPAH) is a rare, autosomal-dominant, inherited disease with low penetrance. Mutations in the bone morphogenetic protein receptor 2 (BMPR2) have been identified in at least 70% of FPAH patients. However, the lifetime penetrance of these BMPR2 mutations is 10% to 20%, suggesting that genetic and/or environmental modifiers are required for disease expression. Our goal in this study was to identify genetic loci that may influence FPAH expression in BMPR2 mutation carriers. We performed a genome-wide linkage scan in 15 FPAH families segregating for BMPR2 mutations. We used a dense single-nucleotide polymorphism (SNP) array and a novel multi-scan linkage procedure that provides increased power and precision for the localization of linked loci. We observed linkage evidence in four regions: 3q22 ([median log of the odds (LOD) = 3.43]), 3p12 (median LOD) = 2.35), 2p22 (median LOD = 2.21), and 13q21 (median LOD = 2.09). When used in conjunction with the non-parametric bootstrap, our approach yields high-resolution to identify candidate gene regions containing putative BMPR2-interacting genes. Imputation of the disease model by LOD-score maximization indicates that the 3q22 locus alone predicts most FPAH cases in BMPR2 mutation carriers, providing strong evidence that BMPR2 and the 3q22 locus interact epistatically. Our findings suggest that genotypes at loci in the newly identified regions, especially at 3q22, could improve FPAH risk prediction in FPAH families. We also suggest other targets for therapeutic intervention.

  6. Bone morphogenetic protein signaling is impaired in an Hfe knockout mouse model of hemochromatosis

    PubMed Central

    Corradini, Elena; Garuti, Cinzia; Montosi, Giuliana; Ventura, Paolo; Andriopoulos, Billy; Lin, Herbert Y.; Pietrangelo, Antonello; Babitt, Jodie L.

    2009-01-01

    Background and Aims Mutations in HFE are the most common cause of the iron-overload disorder hereditary hemochromatosis (HH). Levels of the main iron regulatory hormone, hepcidin, are inappropriately low in HH mouse models and patients with HFE mutations, indicating that HFE regulates hepcidin. The bone morphogenetic protein 6 (BMP6)-SMAD signaling pathway is an important endogenous regulator of hepcidin expression. We investigated whether HFE is involved in BMP6-SMAD regulation of hepcidin expression. Methods The BMP6-SMAD pathway was examined in Hfe knockout (KO) mice and in wild-type (WT) mice as controls. Mice were placed on diets of varying iron content. Hepcidin induction by BMP6 was examined in primary hepatocytes from Hfe KO mice; data were compared with those of WT mice. Results Liver levels of Bmp6 mRNA were higher in Hfe KO mice; these were appropriate for the increased hepatic levels of iron in these mice, compared with WT mice. However, levels of hepatic phosphorylated Smad 1/5/8 protein (an intracellular mediator of Bmp6 signaling) and Id1 mRNA (a target gene of Bmp6) were inappropriately low for the body iron burden and Bmp6 mRNA levels in Hfe KO, compared with WT mice. BMP6 induction of hepcidin expression was reduced in Hfe KO hepatocytes compared with WT hepatocytes. Conclusions HFE is not involved in regulation of BMP6 by iron, but does regulate the downstream signals of BMP6 that are triggered by iron. PMID:19591830

  7. Bone Morphogenetic Proteins in Anterior Cervical Fusion: A Systematic Review and Meta-Analysis.

    PubMed

    Zadegan, Shayan Abdollah; Abedi, Aidin; Jazayeri, Seyed Behnam; Nasiri Bonaki, Hirbod; Jazayeri, Seyed Behzad; Vaccaro, Alexander R; Rahimi-Movaghar, Vafa

    2017-08-01

    Bone morphogenetic proteins (BMPs) have been commonly used as a graft substitute in spinal fusion. Although the U.S. Food and Drug Administration issued a warning on life-threatening complications of recombinant human BMPs (rhBMPs) in cervical spine fusion in 2008, their off-label use has been continued. This investigation aimed to review the evidence for the use of rhBMP-2 and rhBMP-7 in anterior cervical spine fusions. A comprehensive search was performed through Ovid (MEDLINE), PubMed, and Embase. The risk of bias assessment was according to the recommended criteria by the Cochrane Back and Neck group and MINORS (Methodological Index for Non-Randomized Studies). A wide array of radiographic and clinical outcomes including the adverse events were collated. Eighteen articles (1 randomized and 17 nonrandomized) were eligible for inclusion. The fusion rate was higher with use of rhBMP in most studies and our meta-analysis of the pooled data from 4782 patients confirmed this finding (odds ratio, 5.45; P < 0.00001). Altogether, the rhBMP and control groups were comparable in patient-reported outcomes. However, most studies tended to show a significantly higher incidence of overall complication rate, dysphagia/dysphonia, cervical swelling, readmission, wound complications, neurologic complications, and ossification. Application of rhBMPs in cervical spine fusion yields a significantly higher fusion rate with similar patient-reported outcomes, yet increased risk of life-threatening complications. Thus, we do not recommend the use of rhBMP in anterior cervical fusions. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Colloid, adhesive and release properties of nanoparticular ternary complexes between cationic and anionic polysaccharides and basic proteins like bone morphogenetic protein BMP-2.

    PubMed

    Petzold, R; Vehlow, D; Urban, B; Grab, A L; Cavalcanti-Adam, E A; Alt, V; Müller, M

    2017-03-01

    Herein we describe an interfacial local drug delivery system for bone morphogenetic protein 2 (BMP-2) based on coatings of polyelectrolyte complex (PEC) nanoparticles (NP). The application horizon is the functionalization of bone substituting materials (BSM) used for the therapy of systemic bone diseases. Nanoparticular ternary complexes of cationic and anionic polysaccharides and BMP-2 or two further model proteins, respectively, were prepared in dependence of the molar mixing ratio, pH value and of the cationic polysaccharide. As further proteins chymotrypsin (CHY) and papain (PAP) were selected, which served as model proteins for BMP-2 due to similar isoelectric points and molecular weights. As charged polysaccharides ethylenediamine modified cellulose (EDAC) and trimethylammonium modified cellulose (PQ10) were combined with cellulose sulphatesulfate (CS). Mixing diluted cationic and anionic polysaccharide and protein solutions according to a slight either anionic or cationic excess charge colloidal ternary dispersions formed, which were cast onto germanium model substrates by water evaporation. Dynamic light scattering (DLS) demonstrated, that these dispersions were colloidally stable for at least one week. Fourier Transform Infrared (FTIR) showed, that the cast protein loaded PEC NP coatings were irreversibly adhesive at the model substrate in contact to HEPES buffer and solely CHY, PAP and BMP-2 were released within long-term time scale. Advantageously, out of the three proteins BMP-2 showed the smallest initial burst and the slowest release kinetics and around 25% of the initial BMP-2 content were released within 14days. Released BMP-2 showed significant activity in the myoblast cells indicating the ability to regulate the formation of new bone. Therefore, BMP-2 loaded PEC NP are suggested as novel promising tool for the functionalization of BSM used for the therapy of systemic bone diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Radiographic Appearance of Transforaminal Lumbar Interbody Fusion Performed With and Without Recombinant Human Morphogenetic Protein-2.

    PubMed

    Stensby, J Derek; Kaliney, Ryan W; Alford, Bennett; Shen, Francis H; Patrie, James T; Fox, Michael G

    2016-03-01

    The purpose of this study is to determine whether recombinant human morphogenetic protein-2 (rhBMP-2) alters the findings on routine radiographs performed after transforaminal lumbar interbody fusion (TLIF). A retrospective review of 256 TLIF procedures in 200 patients was performed over a 4-year period. The rhBMP-2 group included 204 TLIFs in 160 patients, and the control group included 52 TLIFs in 40 patients. Two musculoskeletal radiologists reviewed the postoperative radiographs for endplate resorption, resorption resolution, new bone formation, bridging bone, and allograft migration. Statistical analysis was performed using logistic regression. The median age was 53 years in the rhBMP-2 group and 54 years in the control group (p = 0.182). The groups were similar with regard to sex (p = 0.517), single or multilevel TLIF (p = 0.921), specific TLIF levels (p = 0.53), and median radiographic follow-up (373 vs 366 days; p = 0.34). Findings that were more common in the rhBMP-2 group than in the control group included endplate resorption (38% [78/204] vs 12% [6/52]; odds ratio [OR], 4.67; 95% CI, 1.99-12.54; p < 0.001), resorption resolution (59% [46/78] vs 0% [0/6]; OR, 8.09; 95% CI, 1.41 to ∞; p = 0.022), new bone formation (84% [171/204] vs 67% [35/52]; OR, 2.51; 95% CI, 1.24-4.99; p = 0.011), bridging bone (55% [112/204] vs 31% [16/52]; OR, 2.73; 95% CI, 1.43-5.34; p = 0.002), and allograft migration (17% [35/204] vs 2% [1/52]; OR, 6.30; 95% CI, 0.91-151.41; p = 0.065). A statistically significant higher frequency of endplate resorption, new bone formation, and bone bridging is present in TLIF augmented by rhBMP-2 compared with TLIF performed without rhBMP-2. Endplate resorption resolves without treatment in most cases after rhBMP-2 use.

  10. Pleiotropic effects of statins on the treatment of chronic periodontitis--a systematic review.

    PubMed

    Estanislau, Ilanna Mara Gomes; Terceiro, Icrólio Ribeiro Colares; Lisboa, Mario Roberto Pontes; Teles, Patrícia de Barros; Carvalho, Rosimary de Sousa; Martins, Ricardo Souza; Moreira, Maria Mônica Studart Mendes

    2015-06-01

    Statins are inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase and are an important group of hypolipidaemic drugs, widely used in the treatment of hypercholesterolaemia and cardiovascular disease. Some studies have shown that statins are able to modulate inflammation and alveolar bone loss. In order to evaluate whether statins could influence periodontal treatment, improving the clinical and radiographic parameters in chronic periodontitis, a systematic review was conducted in the databases PUBMED and BIREME, searching for articles in English and Portuguese, published between the years 2004 and 2014, using the combined keywords statin, periodontal disease, periodontitis and alveolar bone. Studies regarding the treatment of chronic periodontitis in humans, blind or double-blind, retrospective cohort or randomized controlled trials that used statins topically or systemically were selected. Statins have important anti-inflammatory and immune effects, reducing levels of C-reactive protein and matrix metalloproteinases and their intermediate products, such as tumour necrosis factor-α, and are also able to inhibit the adhesion and extravasation of leukocytes, which block the co-stimulation of T cells. Statins reduce bone resorption by inhibiting osteoclast formation and lead to increased apoptosis of these cells. The effect of statins on bone formation is related to the increased gene expression of bone morphogenetic protein in osteoblasts. Although we found biological mechanisms and clinical results that show lower alveolar bone loss and reduction of clinical signs of inflammation, further studies are needed to evaluate the clinical applicability of statins in the routine treatment of chronic periodontitis. © 2014 The British Pharmacological Society.

  11. Regulation of bone morphogenetic protein signalling and cranial osteogenesis by Gpc1 and Gpc3.

    PubMed

    Dwivedi, Prem P; Grose, Randall H; Filmus, Jorge; Hii, Charles S T; Xian, Cory J; Anderson, Peter J; Powell, Barry C

    2013-08-01

    From birth, the vault of the skull grows at a prodigious rate, driven by the activity of osteoblastic cells at the fibrous joints (sutures) that separate the bony calvarial plates. One in 2500 children is born with a medical condition known as craniosynostosis because of premature bony fusion of the calvarial plates and a cessation of bone growth at the sutures. Bone morphogenetic proteins (BMPs) are potent growth factors that promote bone formation. Previously, we found that Glypican-1 (GPC1) and Glypican-3 (GPC3) are expressed in cranial sutures and are decreased during premature suture fusion in children. Although glypicans are known to regulate BMP signalling, a mechanistic link between GPC1, GPC3 and BMPs and osteogenesis has not yet been investigated. We now report that human primary suture mesenchymal cells coexpress GPC1 and GPC3 on the cell surface and release them into the media. We show that they inhibit BMP2, BMP4 and BMP7 activities, which both physically interact with BMP2 and that immunoblockade of endogenous GPC1 and GPC3 potentiates BMP2 activity. In contrast, increased levels of GPC1 and GPC3 as a result of overexpression or the addition of recombinant protein, inhibit BMP2 signalling and BMP2-mediated osteogenesis. We demonstrate that BMP signalling in suture mesenchymal cells is mediated by both SMAD-dependent and SMAD-independent pathways and that GPC1 and GPC3 inhibit both pathways. GPC3 inhibition of BMP2 activity is independent of attachment of the glypican on the cell surface and post-translational glycanation, and thus appears to be mediated by the core glypican protein. The discovery that GPC1 and GPC3 regulate BMP2-mediated osteogenesis, and that inhibition of endogenous GPC1 and GPC3 potentiates BMP2 responsiveness of human suture mesenchymal cells, indicates how downregulation of glypican expression could lead to the bony suture fusion that characterizes craniosynostosis. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Heterozygous Null Bone Morphogenetic Protein Receptor Type 2 Mutations Promote SRC Kinase-dependent Caveolar Trafficking Defects and Endothelial Dysfunction in Pulmonary Arterial Hypertension*

    PubMed Central

    Prewitt, Allison R.; Ghose, Sampa; Frump, Andrea L.; Datta, Arumima; Austin, Eric D.; Kenworthy, Anne K.; de Caestecker, Mark P.

    2015-01-01

    Hereditary pulmonary arterial hypertension (HPAH) is a rare, fatal disease of the pulmonary vasculature. The majority of HPAH patients inherit mutations in the bone morphogenetic protein type 2 receptor gene (BMPR2), but how these promote pulmonary vascular disease is unclear. HPAH patients have features of pulmonary endothelial cell (PEC) dysfunction including increased vascular permeability and perivascular inflammation associated with decreased PEC barrier function. Recently, frameshift mutations in the caveolar structural protein gene Caveolin-1 (CAV-1) were identified in two patients with non-BMPR2-associated HPAH. Because caveolae regulate endothelial function and vascular permeability, we hypothesized that defects in caveolar function might be a common mechanism by which BMPR2 mutations promote pulmonary vascular disease. To explore this, we isolated PECs from mice carrying heterozygous null Bmpr2 mutations (Bmpr2+/−) similar to those found in the majority of HPAH patients. We show that Bmpr2+/− PECs have increased numbers and intracellular localization of caveolae and caveolar structural proteins CAV-1 and Cavin-1 and that these defects are reversed after blocking endocytosis with dynasore. SRC kinase is also constitutively activated in Bmpr2+/− PECs, and localization of CAV-1 to the plasma membrane is restored after treating Bmpr2+/− PECs with the SRC kinase inhibitor 3-(4-chlorophenyl)-1-(1,1-dimethylethyl)-1H-pyrazolo[3,4-d]pyrimidin-4-amine (PP2). Late outgrowth endothelial progenitor cells isolated from HPAH patients show similar increased activation of SRC kinase. Moreover, Bmpr2+/− PECs have impaired endothelial barrier function, and barrier function is restored after treatment with PP2. These data suggest that heterozygous null BMPR2 mutations promote SRC-dependent caveolar trafficking defects in PECs and that this may contribute to pulmonary endothelial barrier dysfunction in HPAH patients. PMID:25411245

  13. Enhanced hyaline cartilage matrix synthesis in collagen sponge scaffolds by using siRNA to stabilize chondrocytes phenotype cultured with bone morphogenetic protein-2 under hypoxia.

    PubMed

    Legendre, Florence; Ollitrault, David; Hervieu, Magalie; Baugé, Catherine; Maneix, Laure; Goux, Didier; Chajra, Hanane; Mallein-Gerin, Frédéric; Boumediene, Karim; Galera, Philippe; Demoor, Magali

    2013-07-01

    Cartilage healing by tissue engineering is an alternative strategy to reconstitute functional tissue after trauma or age-related degeneration. However, chondrocytes, the major player in cartilage homeostasis, do not self-regenerate efficiently and lose their phenotype during osteoarthritis. This process is called dedifferentiation and also occurs during the first expansion step of autologous chondrocyte implantation (ACI). To ensure successful ACI therapy, chondrocytes must be differentiated and capable of synthesizing hyaline cartilage matrix molecules. We therefore developed a safe procedure for redifferentiating human chondrocytes by combining appropriate physicochemical factors: hypoxic conditions, collagen scaffolds, chondrogenic factors (bone morphogenetic protein-2 [BMP-2], and insulin-like growth factor I [IGF-I]) and RNA interference targeting the COL1A1 gene. Redifferentiation of dedifferentiated chondrocytes was evaluated using gene/protein analyses to identify the chondrocyte phenotypic profile. In our conditions, under BMP-2 treatment, redifferentiated and metabolically active chondrocytes synthesized a hyaline-like cartilage matrix characterized by type IIB collagen and aggrecan molecules without any sign of hypertrophy or osteogenesis. In contrast, IGF-I increased both specific and noncharacteristic markers (collagens I and X) of chondrocytes. The specific increase in COL2A1 gene expression observed in the BMP-2 treatment was shown to involve the specific enhancer region of COL2A1 that binds the trans-activators Sox9/L-Sox5/Sox6 and Sp1, which are associated with a decrease in the trans-inhibitors of COL2A1, c-Krox, and p65 subunit of NF-kappaB. Our procedure in which BMP-2 treatment under hypoxia is associated with a COL1A1 siRNA, significantly increased the differentiation index of chondrocytes, and should offer the opportunity to develop new ACI-based therapies in humans.

  14. Degradable Segmented Polyurethane Elastomers for Bone Tissue Engineering: Effect of Polycaprolactone Content

    PubMed Central

    Kavlock, Katherine D.; Whang, Kyumin; Guelcher, Scott A.; Goldstein, Aaron S.

    2016-01-01

    Segmented polyurethanes (PURs) – consisting of degradable poly(α-hydroxy ester) soft segments and amino acid-derived chain extenders – are biocompatible elastomers with tunable mechanical and degradative properties suitable for a variety of tissue engineering applications. In this study, a family of linear PURs synthesized from poly(ε-caprolactone) (PCL) diol, 1,4-diisocyanobutane and tyramine with theoretical PCL contents of 65 to 80 wt% were processed into porous foam scaffolds and evaluated for their ability to support osteoblastic differentiation in vitro. Differential scanning calorimetry and mechanical testing of the foams indicated increasing polymer crystallinity and compressive modulus with increasing PCL content. Next, bone marrow stromal cells (BMSCs) were seeded into PUR scaffolds – as well as poly(lactic-co-glycolic acid) (PLGA) scaffolds – and maintained under osteogenic conditions for 14 and 21 days. Analysis of cell number indicated a systematic decrease in cell density with increasing PUR stiffness at both 14 and 21 days in culture. However, at these same time points the relative mRNA expression for the bone-specific proteins osteocalcin and the growth factors bone morphogenetic protein-2 and vascular endothelial growth factor gene expression were similar among the PURs. Finally, prostaglandin E2 production, alkaline phosphatase activity, and osteopontin mRNA expression were highly elevated on the most-crystalline PUR scaffold as compared to the PLGA and PUR scaffolds. These results suggest that both the modulus and crystallinity of the PUR scaffolds influence cell proliferation and the expression of osteoblastic proteins. PMID:22304961

  15. 3D printed hyperelastic "bone" scaffolds and regional gene therapy: A novel approach to bone healing.

    PubMed

    Alluri, Ram; Jakus, Adam; Bougioukli, Sofia; Pannell, William; Sugiyama, Osamu; Tang, Amy; Shah, Ramille; Lieberman, Jay R

    2018-04-01

    The purpose of this study was to evaluate the viability of human adipose-derived stem cells (ADSCs) transduced with a lentiviral (LV) vector to overexpress bone morphogenetic protein-2 (BMP-2) loaded onto a novel 3D printed scaffold. Human ADSCs were transduced with a LV vector carrying the cDNA for BMP-2. The transduced cells were loaded onto a 3D printed Hyperelastic "Bone" (HB) scaffold. In vitro BMP-2 production was assessed using enzyme-linked immunosorbent assay analysis. The ability of ADSCs loaded on the HB scaffold to induce in vivo bone formation in a hind limb muscle pouch model was assessed in the following groups: ADSCs transduced with LV-BMP-2, LV-green fluorescent protein, ADSCs alone, and empty HB scaffolds. Bone formation was assessed using radiographs, histology and histomorphometry. Transduced ADSCs BMP-2 production on the HB scaffold at 24 hours was similar on 3D printed HB scaffolds versus control wells with transduced cells alone, and continued to increase after 1 and 2 weeks of culture. Bone formation was noted in LV-BMP-2 animals on plain radiographs at 2 and 4 weeks after implantation; no bone formation was noted in the other groups. Histology demonstrated that the LV-BMP-2 group was the only group that formed woven bone and the mean bone area/tissue area was significantly greater when compared with the other groups. 3D printed HB scaffolds are effective carriers for transduced ADSCs to promote bone repair. The combination of gene therapy and tissue engineered scaffolds is a promising multidisciplinary approach to bone repair with significant clinical potential. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1104-1110, 2018. © 2018 Wiley Periodicals, Inc.

  16. Bone Morphogenetic Protein-Induced Msx1 and Msx2 Inhibit Myocardin-Dependent Smooth Muscle Gene Transcription▿

    PubMed Central

    Hayashi, Ken'ichiro; Nakamura, Seiji; Nishida, Wataru; Sobue, Kenji

    2006-01-01

    During the onset and progression of atherosclerosis, the vascular smooth muscle cell (VSMC) phenotype changes from differentiated to dedifferentiated, and in some cases, this change is accompanied by osteogenic transition, resulting in vascular calcification. One characteristic of dedifferentiated VSMCs is the down-regulation of smooth muscle cell (SMC) marker gene expression. Bone morphogenetic proteins (BMPs), which are involved in the induction of osteogenic gene expression, are detected in calcified vasculature. In this study, we found that the BMP2-, BMP4-, and BMP6-induced expression of Msx transcription factors (Msx1 and Msx2) preceded the down-regulation of SMC marker expression in cultured differentiated VSMCs. Either Msx1 or Msx2 markedly reduced the myocardin-dependent promoter activities of SMC marker genes (SM22α and caldesmon). We further investigated interactions between Msx1 and myocardin/serum response factor (SRF)/CArG-box motif (cis element for SRF) using coimmunoprecipitation, gel-shift, and chromatin immunoprecipitation assays. Our results showed that Msx1 or Msx2 formed a ternary complex with SRF and myocardin and inhibited the binding of SRF or SRF/myocardin to the CArG-box motif, resulting in inhibition of their transcription. PMID:17030628

  17. Bone morphogenetic protein-induced MSX1 and MSX2 inhibit myocardin-dependent smooth muscle gene transcription.

    PubMed

    Hayashi, Ken'ichiro; Nakamura, Seiji; Nishida, Wataru; Sobue, Kenji

    2006-12-01

    During the onset and progression of atherosclerosis, the vascular smooth muscle cell (VSMC) phenotype changes from differentiated to dedifferentiated, and in some cases, this change is accompanied by osteogenic transition, resulting in vascular calcification. One characteristic of dedifferentiated VSMCs is the down-regulation of smooth muscle cell (SMC) marker gene expression. Bone morphogenetic proteins (BMPs), which are involved in the induction of osteogenic gene expression, are detected in calcified vasculature. In this study, we found that the BMP2-, BMP4-, and BMP6-induced expression of Msx transcription factors (Msx1 and Msx2) preceded the down-regulation of SMC marker expression in cultured differentiated VSMCs. Either Msx1 or Msx2 markedly reduced the myocardin-dependent promoter activities of SMC marker genes (SM22alpha and caldesmon). We further investigated interactions between Msx1 and myocardin/serum response factor (SRF)/CArG-box motif (cis element for SRF) using coimmunoprecipitation, gel-shift, and chromatin immunoprecipitation assays. Our results showed that Msx1 or Msx2 formed a ternary complex with SRF and myocardin and inhibited the binding of SRF or SRF/myocardin to the CArG-box motif, resulting in inhibition of their transcription.

  18. Anabolic activity of ursolic acid in bone: Stimulating osteoblast differentiation in vitro and inducing new bone formation in vivo.

    PubMed

    Lee, Su-Ui; Park, Sang-Joon; Kwak, Han Bok; Oh, Jaemin; Min, Yong Ki; Kim, Seong Hwan

    2008-01-01

    In the field of osteoporosis, there has been growing interest in anabolic agents that enhance bone mass and improve bone architecture. In this study, we demonstrated that the ubiquitous plant triterpenoid, ursolic acid, enhances differentiation and mineralization of osteoblasts in vitro. We found that ursolic acid induced the expression of osteoblast-specific genes with the activation of mitogen-activated protein kinases, nuclear factor-kappaB, and activator protein-1. Additionally, noggin, an antagonist of bone morphogenetic proteins (BMPs), inhibited ursolic acid-induced osteoblast differentiation. Noggin also inhibited the activation of Smad and the induction of BMP-2 mRNA expression by ursolic acid in the late stage of osteoblast differentiation. Importantly, ursolic acid was shown to have bone-forming activity in vivo in a mouse calvarial bone formation model. A high proportion of positive immunostaining of BMP-2 was found in the nuclear region of woven bone formed by ursolic acid. These results suggested that ursolic acid has the anabolic potential to stimulate osteoblast differentiation and enhance new bone formation.

  19. Quantitative, Structural and Image-based Mechanical Analysis of Nonunion Fracture Repaired by Genetically Engineered Mesenchymal Stem Cells

    PubMed Central

    Kallai, Ilan; van Lenthe, G. Harry; Ruffoni, Davide; Zilberman, Yoram; Müller, Ralph; Pelled, Gadi; Gazit, Dan

    2010-01-01

    Stem cell-mediated gene therapy for fracture repair, utilizes genetically engineered mesenchymal stem cells (MSCs) for the induction of bone growth and is considered a promising approach in skeletal tissue regeneration. Previous studies have shown that murine nonunion fractures can be repaired by implanting MSCs over-expressing recombinant human bone morphogenetic protein-2 (rhBMP-2). Nanoindentation studies of bone tissue induced by MSCs in a radius fracture site indicated similar elastic modulus compared to intact murine bone, eight weeks post treatment. In the present study we sought to investigate temporal changes in microarchitecture and biomechanical properties of repaired murine radius bones, following the implantation of MSCs. High resolution micro computed tomography (Micro-CT) was performed 10 and 35 weeks post MSC implantation, followed by micro finite element (Micro-FE) analysis. The results have shown that the regenerated bone tissue remodels over time, as indicated by a significant decrease in bone volume, total volume and connectivity density combined with an increase in mineral density. In addition, the axial stiffness of limbs repaired with MSCs was 2 to 1.5 times higher compared to the contralateral intact limbs, at 10 and 35 weeks post treatment. These results could be attributed to the fusion that occurred between in the ulna and radius bones. In conclusion, although MSCs induce bone formation, which exceeds the fracture site, significant remodeling of the repair callus occurs over time. In addition, limbs treated with an MSC graft demonstrated superior biomechanical properties, which could indicate the clinical benefit of future MSC application in nonunion fracture repair. PMID:20471652

  20. Complications of anterior cervical discectomy and fusion using recombinant human bone morphogenetic protein-2

    PubMed Central

    Carp, Julia; Sethi, Anil; Bartol, Stephen; Craig, Joseph; Les, Clifford M.

    2007-01-01

    The use of bone morphogenetic protein-2 (rhBMP-2) in spinal fusion has increased dramatically since an FDA approval for its use in anterior lumbar fusion with the LT cage. There are several reports of its use in transforaminal lumbar interbody fusion, posterolateral fusion, and anterior cervical fusion. Reports on adverse effects of rhBMP-2 when used in spinal fusion are scarce in literature. An Institutional Review Board approved retrospective study was conducted in patients undergoing anterior spinal fusion and instrumentation following diskectomy at a single center. Forty-six consecutive patients were included. Twenty-two patients treated with rhBMP-2 and PEEK cages were compared to 24 in whom allograft spacers and demineralized bone matrix was used. Patients filled out Cervical Oswestry Scores, VAS for arm pain, neck pain, and had radiographs preoperatively as well at every follow up visit. Radiographic examination following surgery revealed end plate resorption in all patients in whom rhBMP-2 was used. This was followed by a period of new bone formation commencing at 6 weeks. In contrast, allograft patients showed a progressive blurring of end plate-allograft junction. Dysphagia was a common complication and it was significantly more frequent and more severe in patients in whom rhBMP-2 was used. Post operative swelling anterior to the vertebral body on lateral cervical spine X-ray was significantly larger in the rhBMP-2 group when measured from 1 to 6 weeks after which it was similar. These effects are possibly due to an early inflammatory response to rhBMP-2 and were observed to be dose related. With the parameters we used, there was no significant difference in the clinical outcome of patients in the two groups at 2 years. The cost of implants in patients treated with rhBMP-2 and PEEK spacers was more than three times the cost of allograft spacers and demineralized bone matrix in 1, 2, and 3-level cases. Despite providing consistently good fusion rates, we have abandoned using rhBMP-2 and PEEK cages for anterior cervical fusion, due to the side effects, high cost, and the availability of a suitable alternative. PMID:17387522

  1. Inorganic materials for bone repair or replacement applications.

    PubMed

    Hertz, Audrey; Bruce, Ian J

    2007-12-01

    In recent years, excipient systems have been used increasingly in biomedicine in reconstructive and replacement surgery, as bone cements, drug-delivery vehicles and contrast agents. Particularly, interest has been growing in the development and application of controlled pore inorganic ceramic materials for use in bone-replacement and bone-repair roles and, in this context, attention has been focused on calcium-phosphate, bioactive glasses and SiO2- and TiO2-based materials. It has been shown that inorganic materials that most closely mimic bone structure and surface chemistry most closely function best in bone replacement/repair and, in particular, if a substance possesses a macroporous structure (pores and interconnections >100 microm diameter), then cell infiltration, bone growth and vascularization can all be promoted. The surface roughness and micro/mesoporosity of a material have also been observed to significantly influence its ability to promote apatite nucleation and cell attachment significantly. Pores (where present) can also be packed with pharmaceuticals and biomolecules (e.g., bone morphogenetic proteins [BMPs], which can stimulate bone formation). Finally, the most bio-efficient - in terms of collagen formation and apatite nucleation - materials are those that are able to provide soluble mineralizing species (Si, Ca, PO(4)) at their implant sites and/or are doped or have been surface-activated with specific functional groups. This article presents the context and latest advances in the field of bone-repair materials, especially with respect to the development of bioactive glasses and micro/mesoporous and macroporous inorganic scaffolds. It deals with the possible methods of preparing porous pure/doped or functionalized silicas or their composites, the studies that have been undertaken to evaluate their abilities to act as bone repair scaffolds and also presents future directions for work in that context.

  2. Implant Composed of Demineralized Bone and Mesenchymal Stem Cells Genetically Modified with AdBMP2/AdBMP7 for the Regeneration of Bone Fractures in Ovis aries

    PubMed Central

    Hernandez-Hurtado, Adelina A.; Lara-Arias, Jorge; Romero-Diaz, Viktor J.; Abrego-Guerra, Adalberto; Vilchez-Cavazos, Jose F.; Elizondo-Riojas, Guillermo; Martinez-Rodriguez, Herminia G.; Espinoza-Juarez, Marcela A.; Mendoza Lemus, Oscar F.

    2016-01-01

    Adipose-derived mesenchymal stem cells (ADMSCs) are inducible to an osteogenic phenotype by the bone morphogenetic proteins (BMPs). This facilitates the generation of implants for bone tissue regeneration. This study evaluated the in vitro osteogenic differentiation of ADMSCs transduced individually and in combination with adenoviral vectors expressing BMP2 and BMP7. Moreover, the effectiveness of the implant containing ADMSCs transduced with the adenoviral vectors AdBMP2/AdBMP7 and embedded in demineralized bone matrix (DBM) was tested in a model of tibial fracture in sheep. This graft was compared to ewes implanted with untransduced ADMSCs embedded in the same matrix and with injured but untreated animals. In vivo results showed accelerated osteogenesis in the group treated with the AdBMP2/AdBMP7 transduced ADMSC graft, which also showed improved restoration of the normal bone morphology. PMID:27818692

  3. Developmental Regulation of the Growth Plate and Cranial Synchondrosis

    PubMed Central

    Wei, X.; Hu, M.; Mishina, Y.; Liu, F.

    2016-01-01

    Long bones and the cranial base are both formed through endochondral ossification. Elongation of long bones is primarily through the growth plate, which is a cartilaginous structure at the end of long bones made up of chondrocytes. Growth plate chondrocytes are organized in columns along the longitudinal axis of bone growth. The cranial base is the growth center of the neurocranium. Synchondroses, consisting of mirror-image growth plates, are critical for cranial base elongation and development. Over the last decade, considerable progress has been made in determining the roles of the parathyroid hormone–related protein, Indian hedgehog, fibroblast growth factor, bone morphogenetic protein, and Wnt signaling pathways in various aspects of skeletal development. Furthermore, recent evidence indicates the important role of the primary cilia signaling pathway in bone elongation. Here, we review the development of the growth plate and cranial synchondrosis and the regulation by the above-mentioned signaling pathways, highlighting the similarities and differences between these 2 structures. PMID:27250655

  4. Bone regeneration by polyhedral microcrystals from silkworm virus

    PubMed Central

    Matsumoto, Goichi; Ueda, Takayo; Shimoyama, Junko; Ijiri, Hiroshi; Omi, Yasushi; Yube, Hisato; Sugita, Yoshihiko; Kubo, Katsutoshi; Maeda, Hatsuhiko; Kinoshita, Yukihiko; Arias, Duverney Gaviria; Shimabukuro, Junji; Kotani, Eiji; Kawamata, Shin; Mori, Hajime

    2012-01-01

    Bombyx mori cypovirus is a major pathogen which causes significant losses in silkworm cocoon harvests because the virus particles are embedded in micrometer-sized protein crystals called polyhedra and can remain infectious in harsh environmental conditions for years. But the remarkable stability of polyhedra can be applied on slow-release carriers of cytokines for tissue engineering. Here we show the complete healing in critical-sized bone defects by bone morphogenetic protein-2 (BMP-2) encapsulated polyhedra. Although absorbable collagen sponge (ACS) safely and effectively delivers recombinant human BMP-2 (rhBMP-2) into healing tissue, the current therapeutic regimens release rhBMP-2 at an initially high rate after which the rate declines rapidly. ACS impregnated with BMP-2 polyhedra had enough osteogenic activity to promote complete healing in critical-sized bone defects, but ACS with a high dose of rhBMP-2 showed incomplete bone healing, indicating that polyhedral microcrystals containing BMP-2 promise to advance the state of the art of bone healing. PMID:23226833

  5. BMP-non-responsive Sca1+ CD73+ CD44+ mouse bone marrow derived osteoprogenitor cells respond to combination of VEGF and BMP-6 to display enhanced osteoblastic differentiation and ectopic bone formation.

    PubMed

    Madhu, Vedavathi; Li, Ching-Ju; Dighe, Abhijit S; Balian, Gary; Cui, Quanjun

    2014-01-01

    Clinical trials on fracture repair have challenged the effectiveness of bone morphogenetic proteins (BMPs) but suggest that delivery of mesenchymal stem cells (MSCs) might be beneficial. It has also been reported that BMPs could not increase mineralization in several MSCs populations, which adds ambiguity to the use of BMPs. However, an exogenous supply of MSCs combined with vascular endothelial growth factor (VEGF) and BMPs is reported to synergistically enhance fracture repair in animal models. To elucidate the mechanism of this synergy, we investigated the osteoblastic differentiation of cloned mouse bone marrow derived MSCs (D1 cells) in vitro in response to human recombinant proteins of VEGF, BMPs (-2, -4, -6, -9) and the combination of VEGF with BMP-6 (most potent BMP). We further investigated ectopic bone formation induced by MSCs pre-conditioned with VEGF, BMP-6 or both. No significant increase in mineralization, phosphorylation of Smads 1/5/8 and expression of the ALP, COL1A1 and osterix genes was observed upon addition of VEGF or BMPs alone to the cells in culture. The lack of CD105, Alk1 and Alk6 expression in D1 cells correlated with poor response to BMPs indicating that a greater care in the selection of MSCs is necessary. Interestingly, the combination of VEGF and BMP-6 significantly increased the expression of ALP, COL1A1 and osterix genes and D1 cells pre-conditioned with VEGF and BMP-6 induced greater bone formation in vivo than the non-conditioned control cells or the cells pre-conditioned with either VEGF or BMP-6 alone. This enhanced bone formation by MSCs correlated with higher CADM1 expression and OPG/RANKL ratio in the implants. Thus, combined action of VEGF and BMP on MSCs enhances osteoblastic differentiation of MSCs and increases their bone forming ability, which cannot be achieved through use of BMPs alone. This strategy can be effectively used for bone repair.

  6. Treatment of heterotopic ossification through remote ATP hydrolysis.

    PubMed

    Peterson, Jonathan R; De La Rosa, Sara; Eboda, Oluwatobi; Cilwa, Katherine E; Agarwal, Shailesh; Buchman, Steven R; Cederna, Paul S; Xi, Chuanwu; Morris, Michael D; Herndon, David N; Xiao, Wenzhong; Tompkins, Ronald G; Krebsbach, Paul H; Wang, Stewart C; Levi, Benjamin

    2014-09-24

    Heterotopic ossification (HO) is the pathologic development of ectopic bone in soft tissues because of a local or systemic inflammatory insult, such as burn injury or trauma. In HO, mesenchymal stem cells (MSCs) are inappropriately activated to undergo osteogenic differentiation. Through the correlation of in vitro assays and in vivo studies (dorsal scald burn with Achilles tenotomy), we have shown that burn injury enhances the osteogenic potential of MSCs and causes ectopic endochondral heterotopic bone formation and functional contractures through bone morphogenetic protein-mediated canonical SMAD signaling. We further demonstrated a prevention strategy for HO through adenosine triphosphate (ATP) hydrolysis at the burn site using apyrase. Burn site apyrase treatment decreased ATP, increased adenosine 3',5'-monophosphate, and decreased phosphorylation of SMAD1/5/8 in MSCs in vitro. This ATP hydrolysis also decreased HO formation and mitigated functional impairment in vivo. Similarly, selective inhibition of SMAD1/5/8 phosphorylation with LDN-193189 decreased HO formation and increased range of motion at the injury site in our burn model in vivo. Our results suggest that burn injury-exacerbated HO formation can be treated through therapeutics that target burn site ATP hydrolysis and modulation of SMAD1/5/8 phosphorylation. Copyright © 2014, American Association for the Advancement of Science.

  7. Programmable Mechanobioreactor for Exploration of the Effects of Periodic Vibratory Stimulus on Mesenchymal Stem Cell Differentiation

    PubMed Central

    Cashion, Avery T.; Caballero, Montserrat; Halevi, Alexandra; Pappa, Andrew; Dennis, Robert G.

    2014-01-01

    Abstract A programmable bioreactor using a voice-coil actuator was developed to enable research on the effects of periodic vibratory stimulus on human and porcine mesenchymal stem cells (MSCs). We hypothesized that low frequency vibrations would result in a cartilage phenotype and higher frequency vibrations would result in a bone phenotype. The mechanical stimulation protocol is adjusted from a computer external to the incubator via a USB cable. Once programmed, the embedded microprocessor and sensor system on the bioreactor execute the protocol independent of the computer. In each test, a sinusoidal stimulus was applied to a culture plate in 1-min intervals with a 15-min rest following each, for a total of 15 h per day for 10 days. Frequencies of 1 and 100 Hz were applied to cultures of both human and porcine umbilical cord–derived MSCs. Chondrogenesis was determined by Alcian blue staining for glycosaminoglycans and an increased differentiation index (ratio of mRNA for collagen II and collagen I). Osteogenic differentiation was indicated with Alizarin red for calcium staining and increased bone morphogenetic protein 2 mRNA. One-hertz stimulation resulted in a cartilage phenotype for both human and porcine MSCs, while 100-Hz stimulation resulted in a bone phenotype. PMID:24570842

  8. Bone morphogenetic protein antagonist gene NOG is involved in myeloproliferative disease associated with myelofibrosis.

    PubMed

    Andrieux, Joris; Roche-Lestienne, Catherine; Geffroy, Sandrine; Desterke, Christophe; Grardel, Nathalie; Plantier, Isabelle; Selleslag, Dominik; Demory, Jean-Loup; Laï, Jean-Luc; Leleu, Xavier; Le Bousse-Kerdiles, Caroline; Vandenberghe, Peter

    2007-10-01

    In a case with secondary myelofibrosis occurring after essential thrombocythemia, cytogenetic analysis revealed an isolated translocation t(X;17)(q27;q22) in all cells. We found that a bacterial artificial chromosome (BAC) encompassing the breakpoint on chromosome 17 long arm contained only one gene, NOG. We therefore investigated the occurrence of this rare breakpoint in myeloproliferative disorders (MPDs). We identified three more patients with a 17q abnormality in MPDs: myelofibrosis with myeloid metaplasia (MMM); chronic myeloid leukemia positive for t(9;22)(q34;q11) with additional t(4;17)(p15;q22) at diagnosis; and myelofibrosis complicating polycythemia vera. All three cases exhibited a split of BACs containing NOG. The protein encoded by NOG, noggin, acts as an antagonist to bone morphogenetic secreted protein 2 and 4 (BMP2 and BMP4). A comparative analysis of gene expression on Agilent 22K oligonucleotide microarrays in purified CD34+ cells from the blood of MMM patients showed significant downregulation of BMPR2, BMPR1B, BMP2, and BMP8; upregulation of BMP3 and BMP10; and a trend to lower expression of NOG. Thus, given that expression and release of BMPs are important in the induction of osteosclerosis and angiogenic activity, the observed BMP deregulations could be triggered by potential NOG genetic alterations in the four cases here described, and may contribute to the myelofibrotic process characterized by bone marrow stromal reaction including collagen fibrosis, osteosclerosis, and angiogenesis.

  9. Hyaline cartilage regeneration by combined therapy of microfracture and long-term bone morphogenetic protein-2 delivery.

    PubMed

    Yang, Hee Seok; La, Wan-Geun; Bhang, Suk Ho; Kim, Hak-Jun; Im, Gun-Il; Lee, Haeshin; Park, Jung-Ho; Kim, Byung-Soo

    2011-07-01

    Microfracture of cartilage induces migration of bone-marrow-derived mesenchymal stem cells. However, this treatment often results in fibrocartilage regeneration. Growth factors such as bone morphogenetic protein (BMP)-2 induce the differentiation of bone-marrow-derived mesenchymal stem cells into chondrocytes, which can be used for hyaline cartilage regeneration. Here, we tested the hypothesis that long-term delivery of BMP-2 to cartilage defects subjected to microfracture results in regeneration of high-quality hyaline-like cartilage, as opposed to short-term delivery of BMP-2 or no BMP-2 delivery. Heparin-conjugated fibrin (HCF) and normal fibrin were used as carriers for the long- and short-term delivery of BMP-2, respectively. Rabbit articular cartilage defects were treated with microfracture combined with one of the following: no treatment, fibrin, short-term delivery of BMP-2, HCF, or long-term delivery of BMP-2. Eight weeks after treatment, histological analysis revealed that the long-term delivery of BMP-2 group (microfracture + HCF + BMP-2) showed the most staining with alcian blue. A biochemical assay, real-time polymerase chain reaction assay and Western blot analysis all revealed that the long-term delivery of BMP-2 group had the highest glucosaminoglycan content as well as the highest expression level of collagen type II. Taken together, the long-term delivery of BMP-2 to cartilage defects subjected to microfracture resulted in regeneration of hyaline-like cartilage, as opposed to short-term delivery or no BMP-2 delivery. Therefore, this method could be more convenient for hyaline cartilage regeneration than autologous chondrocyte implantation due to its less invasive nature and lack of cell implantation.

  10. Magnesium modification up-regulates the bioactivity of bone morphogenetic protein-2 upon calcium phosphate cement via enhanced BMP receptor recognition and Smad signaling pathway.

    PubMed

    Ding, Sai; Zhang, Jing; Tian, Yu; Huang, Baolin; Yuan, Yuan; Liu, Changsheng

    2016-09-01

    Efficient presentation of growth factors is one of the great challenges in tissue engineering. In living systems, bioactive factors exist in soluble as well as in matrix-bound forms, both of which play an integral role in regulating cell behaviors. Herein, effect of magnesium on osteogenic bioactivity of recombinant human bone morphogenetic protein-2 (rhBMP-2) was investigated systematically with a series of Mg modified calcium phosphate cements (xMCPCs, x means the content of magnesium phosphate cement wt%) as matrix model. The results indicated that the MCPC, especially 5MCPC, could promote the rhBMP-2-induced in vitro osteogenic differentiation via Smad signaling of C2C12 cells. Further studies demonstrated that all MCPC substrates exhibited similar rhBMP-2 release rate and preserved comparable conformation and biological activity of the released rhBMP-2. Also, the ionic extracts of MCPC made little difference to the bioactivity of rhBMP-2, either in soluble or in matrix-bound forms. However, with the quartz crystal microbalance (QCM), we observed a noticeable enhancement of rhBMP-2 mass-uptake on 5MCPC as well as a better recognition of the bound rhBMP-2 to BMPR IA and BMPR II. In vivo results demonstrated a better bone regeneration capacity of 5MCPC/rhBMP-2. From the above, our results demonstrated that it was the Mg anchored on the underlying substrates that tailored the way of rhBMP-2 bound on MCPC, and thus facilitated the recognition of BMPRs to stimulate osteogenic differentiation. The study will guide the development of Mg-doped bioactive bone implants for tissue regeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. [The role of Smads and related transcription factors in the signal transduction of bone morphogenetic protein inducing bone formation].

    PubMed

    Xu, Xiao-liang; Dai, Ke-rong; Tang, Ting-ting

    2003-09-01

    To clarify the mechanisms of the signal transduction of bone morphogenetic proteins (BMPs) inducing bone formation and to provide theoretical basis for basic and applying research of BMPs. We looked up the literature of the role of Smads and related transcription factors in the signal transduction of BMPs inducing bone formation. The signal transduction processes of BMPs included: 1. BMPs combined with type II and type I receptors; 2. the type I receptor phosphorylated Smads; and 3. Smads entered the cell nucleus, interacted with transcription factors and influenced the transcription of related proteins. Smads could be divided into receptor-regulated Smads (R-Smads: Smad1, Smad2, Smad3, Smad5, Smad8 and Smad9), common-mediator Smad (co-Smad: Smad4), and inhibitory Smads (I-Smads: Smad6 and Smad7). Smad1, Smad5, Smad8, and probable Smad9 were involved in the signal transduction of BMPs. Multiple kinases, such as focal adhesion kinase (FAK), Ras-extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K), and Akt serine/threonine kinase were related to Smads signal transduction. Smad1 and Smad5 related with transcription factors included core binding factor A1 (CBFA1), smad-interacting protein 1 (SIP1), ornithine decarboxylase antizyme (OAZ), activating protein-1 (AP-1), xenopus ventralizing homeobox protein-2 (Xvent-2), sandostatin (Ski), antiproliferative proteins (Tob), and homeodomain-containing transcriptian factor-8 (Hoxc-8), et al. CBFA1 could interact with Smad1, Smad2, Smad3, and Smad5, so it was involved in TGF-beta and BMP-2 signal transduction, and played an important role in the bone formation. Cleidocranial dysplasia (CCD) was thought to be caused by heterozygous mutations in CBFA1. The CBFA1 knockout mice showed no osteogenesis and had maturational disturbance of chondrocytes. Smads and related transcription factors, especially Smad1, Smad5, Smad8 and CBFA1, play an important role in the signal transduction of BMPs inducing bone formation.

  12. A comparison of radiographic and clinical outcomes of anterior lumbar interbody fusion performed with either a cellular bone allograft containing multipotent adult progenitor cells or recombinant human bone morphogenetic protein-2.

    PubMed

    Lee, Daniel Dongwhan; Kim, John Yongmin

    2017-08-25

    Both the map3 Cellular Allogeneic Bone Graft® and recombinant human bone morphogenetic protein 2 (rhBMP-2, Infuse®) were developed to provide an alternative to iliac crest autograft, thus eliminating the morbidity associated with its harvest. The recent literature concerning adverse events associated with the use of rhBMP-2, however, highlights the need for a safe and effective alternative. The multipotent adult progenitor cells (MAPC) found in map3 allograft may provide this alternative. The purpose of this study is to report 1-year outcomes of patients treated via anterior lumbar interbody fusion (ALIF) using either map3 Cellular Allogeneic Bone Graft or rhBMP-2 for bony fusion. This was a retrospective evaluation of 41 patients treated via ALIF with either map3 or rhBMP-2 in a polyetheretherketone cage with posterior stabilization at 1, 2, or 3 consecutive levels (L3-S1). Patients were equally divided between treatment groups. The Oswestry Disability Index (ODI) and visual analog scores (VAS) for pain were documented as part of the standard of care. An independent radiologist assessed bridging of bone, disc height, and lordosis. Primary outcome measures included radiographic analysis of fusion by plain film and CTs. Secondary clinical outcomes included visual analogue scale for neck and arm pain and low back disability index scores. The overall fusion rate was 91%, with no significant difference between groups. Improvements in ODI and VAS were observed among all patients (p < 0.001), with no significant difference between groups for ODI (p = 0.966) or VAS (p = 0.251). There was no significant difference in terms of changes to disc height and lordosis between groups (p < 0.05). The rhBMP-2 group had increased post-operative complications when compared to the map3 group, but the low numbers precluded statistical analysis. Improvements in radiographic and clinical findings were observed in both treatment groups one-year postoperatively. Map3 allograft demonstrated equivalent fusion rates to rhBMP-2. A review of surgical supply costs at the treatment facility favored map3 allograft for the treatment of patients with DDD undergoing an ALIF in 1-3 levels compared to rhBMP-2. Further studies to evaluate long-term outcomes and post-operative complications are required.

  13. Functional Differentiation of Uterine Stromal Cells Involves Cross-regulation between Bone Morphogenetic Protein 2 and Kruppel-like Factor (KLF) Family Members KLF9 and KLF13

    USDA-ARS?s Scientific Manuscript database

    The inability of the uterine epithelium to enter a state of receptivity for the embryo to implant is a significant underlying cause of early pregnancy loss. We previously showed that mice null for the Progesterone Receptor (PGR)-interacting protein Kruppel-like Factor (KLF) 9 are subfertile and exhi...

  14. Bone morphogenetic protein 2 (bmp2) and krüppel-like factor 9 (klf9) cross-regulation in uterine stromal cells promotes timing of uterine endometrial receptivity

    USDA-ARS?s Scientific Manuscript database

    Our laboratory has identified a novel progesterone receptor (PGR) co-activator protein, designated Krüppel-like Factor 9 (KLF9), whose absence in mice is associated with subfertility with decreased number of implanting embryos due to altered patterns of proliferation, apoptosis and aberrant P-respon...

  15. [Morphogenetic foundations for increased evolutionary complexity in the organization of thecate hydroids shoots (Cnidaria, Hydroidomedusa, Leptomedusae)].

    PubMed

    Kosevich, I A

    2012-01-01

    The morphogenetic approach is applied to analyze the diversity of spatial organization of shoots in thecate hydroids (Cnidaria, Hydroidomedusa, Leptomedusae). The main tendencies and constraints of increased evolutionary complexity in thecate hydroids colonies are uncovered.

  16. Derangement of calcium metabolism in diabetes mellitus: negative outcome from the synergy between impaired bone turnover and intestinal calcium absorption.

    PubMed

    Wongdee, Kannikar; Krishnamra, Nateetip; Charoenphandhu, Narattaphol

    2017-01-01

    Both types 1 and 2 diabetes mellitus (T1DM and T2DM) are associated with profound deterioration of calcium and bone metabolism, partly from impaired intestinal calcium absorption, leading to a reduction in calcium uptake into the body. T1DM is associated with low bone mineral density (BMD) and osteoporosis, whereas the skeletal changes in T2DM are variable, ranging from normal to increased and to decreased BMD. However, both types of DM eventually compromise bone quality through production of advanced glycation end products and misalignment of collagen fibrils (so-called matrix failure), thereby culminating in a reduction of bone strength. The underlying cellular mechanisms (cellular failure) are related to suppression of osteoblast-induced bone formation and bone calcium accretion, as well as to enhancement of osteoclast-induced bone resorption. Several other T2DM-related pathophysiological changes, e.g., osteoblast insulin resistance, impaired productions of osteogenic growth factors (particularly insulin-like growth factor 1 and bone morphogenetic proteins), overproduction of pro-inflammatory cytokines, hyperglycemia, and dyslipidemia, also aggravate diabetic osteopathy. In the kidney, DM and the resultant hyperglycemia lead to calciuresis and hypercalciuria in both humans and rodents. Furthermore, DM causes deranged functions of endocrine factors related to mineral metabolism, e.g., parathyroid hormone, 1,25-dihydroxyvitamin D 3 , and fibroblast growth factor-23. Despite the wealth of information regarding impaired bone remodeling in DM, the long-lasting effects of DM on calcium metabolism in young growing individuals, pregnant women, and neonates born to women with gestational DM have received scant attention, and their underlying mechanisms are almost unknown and worth exploring.

  17. [Progress of Masquelet technique to repair bone defect].

    PubMed

    Yin, Qudong; Sun, Zhenzhong; Gu, Sanjun

    2013-10-01

    To summarize the progress of Masquelet technique to repair bone defect. The recent literature concerning the application of Masquelet technique to repair bone defect was extensively reviewed and summarized. Masquelet technique involves a two-step procedure. First, bone cement is used to fill the bone defect after a thorough debridement, and an induced membrane structure surrounding the spacer formed; then the bone cement is removed after 6-8 weeks, and rich cancellous bone is implanted into the induced membrane. Massive cortical bone defect is repaired by new bone forming and consolidation. Experiments show that the induced membrane has vascular system and is also rich in vascular endothelial growth factor, transforming growth factor beta1, bone morphogenetic protein 2, and bone progenitor cells, so it has osteoinductive property; satisfactory results have been achieved in clinical application of almost all parts of defects, various types of bone defect and massive defect up to 25 cm long. Compared with other repair methods, Masquelet technique has the advantages of reliable effect, easy to operate, few complications, low requirements for recipient site, and wide application. Masquelet technique is an effective method to repair bone defect and is suitable for various types of bone defect, especially for bone defects caused by infection and tumor resection.

  18. Integration of 3D Printed and Micropatterned Polycaprolactone Scaffolds for Guidance of Oriented Collagenous Tissue Formation In Vivo.

    PubMed

    Pilipchuk, Sophia P; Monje, Alberto; Jiao, Yizu; Hao, Jie; Kruger, Laura; Flanagan, Colleen L; Hollister, Scott J; Giannobile, William V

    2016-03-01

    Scaffold design incorporating multiscale cues for clinically relevant, aligned tissue regeneration has potential to improve structural and functional integrity of multitissue interfaces. The objective of this preclinical study is to develop poly(ε-caprolactone) (PCL) scaffolds with mesoscale and microscale architectural cues specific to human ligament progenitor cells and assess their ability to form aligned bone-ligament-cementum complexes in vivo. PCL scaffolds are designed to integrate a 3D printed bone region with a micropatterned PCL thin film consisting of grooved pillars. The patterned film region is seeded with human ligament cells, fibroblasts transduced with bone morphogenetic protein-7 genes seeded within the bone region, and a tooth dentin segment positioned on the ligament region prior to subcutaneous implantation into a murine model. Results indicate increased tissue alignment in vivo using micropatterned PCL films, compared to random-porous PCL. At week 6, 30 μm groove depth significantly enhances oriented collagen fiber thickness, overall cell alignment, and nuclear elongation relative to 10 μm groove depth. This study demonstrates for the first time that scaffolds with combined hierarchical mesoscale and microscale features can align cells in vivo for oral tissue repair with potential for improving the regenerative response of other bone-ligament complexes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. [Sustained release of recombinant human bone morphogenetic protein-2 combined with stromal vascular fraction cells in promoting posterolateral spinal fusion in rat model].

    PubMed

    Yuan, Wei; Zheng, Jun; Qian, Jinyu; Zhou, Xiaoxiao; Wang, Minghui; Wang, Xiuhui

    2017-07-01

    To observe the effect of stromal vascular fraction cells (SVFs) from rat fat tissue combined with sustained release of recombinant human bone morphogenetic protein-2 (rhBMP-2) in promoting the lumbar fusion in rat model. SVFs were harvested from subcutaneous fat of bilateral inguinal region of 4-month-old rat through the collagenase I digestion. The sustained release carrier was prepared via covalent bond of the rhBMP-2 and β-tricalcium phosphate (β-TCP) by the biominetic apatite coating process. The sustained release effect was measured by BCA method. Thirty-two rats were selected to establish the posterolateral lumbar fusion model and were divided into 4 groups, 8 rats each group. The decalcified bone matrix (DBX) scaffold+PBS, DBX scaffold+rhBMP-2/β-TCP sustained release carrier, DBX scaffold+SVFs, and DBX scaffold+rhBMP-2/β-TCP sustained release carrier+SVFs were implanted in groups A, B, C, and D respectively. X-ray films, manual spine palpation, and high-resolution micro-CT were used to evaluate spinal fusion at 8 weeks after operation; bone mineral density (BMD) and bone volume fraction were analyzed; the new bone formation was evaluated by HE staining and Masson's trichrome staining, osteocalcin (OCN) was detected by immunohistochemical staining. The cumulative release amount of rhBMP-2 was about 40% at 2 weeks, indicating sustained release effect of rhBMP-2; while the control group was almost released within 2 weeks. At 8 weeks, the combination of manual spine palpation, X-ray, and micro-CT evaluation showed that group D had the strongest bone formation (100%, 8/8), followed by group B (75%, 6/8), group C (37.5%, 3/8), and group A (12.5%, 1/8). Micro-CT analysis showed BMD and bone volume fraction were significantly higher in group D than groups A, B, and C ( P <0.05), and in group B than groups A and C ( P <0.05). HE staining, Masson's trichrome staining, and immunohistochemistry staining for OCN staining exhibited a large number of cartilage cells with bone matrix deposition, and an active osteogenic process similar to the mineralization of long bones in group D. The bone formation of group B was weaker than that of group D, and there was no effective new bone formation in groups A and C. The combination of sustained release of rhBMP-2 and freshly SVFs can significantly promote spinal fusion in rat model, providing a theoretical basis for further clinical applications.

  20. Human alveolar bone cell proliferation, expression of osteoblastic phenotype, and matrix mineralization on porous titanium produced by powder metallurgy.

    PubMed

    Rosa, Adalberto Luiz; Crippa, Grasiele Edilaine; de Oliveira, Paulo Tambasco; Taba, Mario; Lefebvre, Louis-Philippe; Beloti, Marcio Mateus

    2009-05-01

    This study aimed at investigating the influence of the porous titanium (Ti) structure on the osteogenic cell behaviour. Porous Ti discs were fabricated by the powder metallurgy process with the pore size typically between 50 and 400 microm and a porosity of 60%. Osteogenic cells obtained from human alveolar bone were cultured until subconfluence and subcultured on dense Ti (control) and porous Ti for periods of up to 17 days. Cultures grown on porous Ti exhibited increased cell proliferation and total protein content, and lower levels of alkaline phosphatase (ALP) activity than on dense Ti. In general, gene expression of osteoblastic markers-runt-related transcription factor 2, collagen type I, alkaline phosphatase, bone morphogenetic protein-7, and osteocalcin was lower at day 7 and higher at day 17 in cultures grown on porous Ti compared with dense Ti, a finding consistent with the enhanced growth rate for such cultures. The amount of mineralized matrix was greater on porous Ti compared with the dense one. These results indicate that the porous Ti is an appropriate substrate for osteogenic cell adhesion, proliferation, and production of a mineralized matrix. Because of the three-dimensional environment it provides, porous Ti should be considered an advantageous substrate for promoting desirable implant surface-bone interactions.

  1. Osteogenic Response to BMP-2 of hMSCs Grown on Apatite-Coated Scaffolds

    PubMed Central

    Davis, Hillary E.; Case, Erin M.; Miller, Stephanie L.; Genetos, Damian C.; Leach, J. Kent

    2011-01-01

    Osteoconductive materials play a critical role in promoting integration with surrounding bone tissue and resultant bone repair in vivo. However, the impact of 3D osteoconductive substrates coupled with soluble signals on progenitor cell differentiation is not clear. In this study, we investigated the influence of bone morphogenetic protein-2 (BMP-2) concentration on the osteogenic differentiation of human mesenchymal stem cells (hMSCs) when seeded in carbonated apatite-coated polymer scaffolds. Mineralized scaffolds were more hydrophilic and adsorbed more BMP-2 compared to nonmineralized scaffolds. Changes in alkaline phosphatase (ALP) activity within stimulated hMSCs were dependent on the dose of BMP-2 and the scaffold composition. We detected more cell-secreted calcium on mineralized scaffolds at all time points, and higher BMP-2 concentrations resulted in increased ALP and calcium levels. RUNX2 and IBSP gene expression within hMSCs was affected by both substrate and soluble signals, SP7 by soluble factors, and SPARC by substrate-mediated cues. The present data indicate that a combination of apatite and BMP-2 do not simply enhance the osteogenic response of hMSCs, but act through multiple pathways that may be both substrate- and growth factor-mediated. Thus, multiple signaling strategies will likely be necessary to achieve optimal bone regeneration. PMID:21656707

  2. Using eddy currents for noninvasive in vivo pH monitoring for bone tissue engineering.

    PubMed

    Beck-Broichsitter, Benedicta E; Daschner, Frank; Christofzik, David W; Knöchel, Reinhard; Wiltfang, Jörg; Becker, Stephan T

    2015-03-01

    The metabolic processes that regulate bone healing and bone induction in tissue engineering models are not fully understood. Eddy current excitation is widely used in technical approaches and in the food industry. The aim of this study was to establish eddy current excitation for monitoring metabolic processes during heterotopic osteoinduction in vivo. Hydroxyapatite scaffolds were implanted into the musculus latissimus dorsi of six rats. Bone morphogenetic protein 2 (BMP-2) was applied 1 and 2 weeks after implantation. Weekly eddy current excitation measurements were performed. Additionally, invasive pH measurements were obtained from the scaffolds using fiber optic detection devices. Correlations between the eddy current measurements and the metabolic values were calculated. The eddy current measurements and pH values decreased significantly in the first 2 weeks of the study, followed by a steady increase and stabilization at higher levels towards the end of the study. The measurement curves and statistical evaluations indicated a significant correlation between the resonance frequency values of the eddy current excitation measurements and the observed pH levels (p = 0.0041). This innovative technique was capable of noninvasively monitoring metabolic processes in living tissues according to pH values, showing a direct correlation between eddy current excitation and pH in an in vivo tissue engineering model.

  3. Morphologic and molecular alteration during tibia fracture healing in rat.

    PubMed

    Yu, M-D; Su, B-H; Zhang, X-X

    2018-03-01

    To monitor morphological feature and related osteogenic and bone metabolic change during healing of tibia fracture in a rat model. Tibia density and trabecular thickness were evaluated. Histopathology was examined by HE staining. Serous inflammatory factors IL-4, IL-6, TNF-α and metabolic biomarkers ALP, β-CTX, P1NP, were determined by ELISA. The expression of RUNX2, TGF-β1, VEGF-α, BMP-2, BMP-4, and BMP-7 in callus tissue were qualified by RT-PCR. Bone density decreased until week 4 and then increased post-operation. Trabeculae in callus were thickened over time with active osteogenesis. ELISA indicated the most severe inflammation at week 2, with the highest level of TNF-α, IL-6, and the lowest level of IL-4. After 4 weeks, the inflammation was alleviated accompanying with the decline of TNF-α and IL-6, while there was the elevation of IL-4. Bone metabolism showed active osteogenesis and resorption at week 6 with high P1NP and β-CTX. The expression of RUNX2, TGF-β1, VEGF-α, BMP-2, BMP-4, and BMP-7 increased progressively from week 1 to 6. The major lesions at week 2 in sham were tissue necrosis, periosteal reactive hyperplasia, inflammatory cell infiltration, capillary hyperplasia and slight fibro-blast cytopoiesis. At week 4, proliferation was greatly activated, fibrous callus shaped and chondrogenesis and some osteogenesis occurred at week 8. In rat model, bone density started to increase at week 6 after fracture, accompanied with trabeculae thickening, serous inflammatory factors decline, and peaked bone morphogenetic protein/growth factors, which indicated active osteogenesis was conforming to the classical phase of secondary fracture healing.

  4. Dual Delivery of EPO and BMP2 from a Novel Modular Poly-ɛ-Caprolactone Construct to Increase the Bone Formation in Prefabricated Bone Flaps

    PubMed Central

    Patel, Janki Jayesh; Modes, Jane E.; Flanagan, Colleen L.; Krebsbach, Paul H.; Edwards, Sean P.

    2015-01-01

    Poly-ɛ-caprolactone (PCL) is a biocompatible polymer that has mechanical properties suitable for bone tissue engineering; however, it must be integrated with biologics to stimulate bone formation. Bone morphogenetic protein-2 (BMP2) delivered from PCL produces bone when implanted subcutaneously, and erythropoietin (EPO) works synergistically with BMP2. In this study, EPO and BMP2 are adsorbed separately on two 3D-printed PCL scaffold modules that are assembled for codelivery on a single scaffold structure. This assembled modular PCL scaffold with dual BMP2 and EPO delivery was shown to increase bone growth in an ectopic location when compared with BMP2 delivery along a replicate scaffold structure. EPO (200 IU/mL) and BMP2 (65 μg/mL) were adsorbed onto the outer and inner portions of a modular scaffold, respectively. Protein binding and release studies were first quantified. Subsequently, EPO+BMP2 and BMP2 scaffolds were implanted subcutaneously in mice for 4 and 8 weeks, and the regenerated bone was analyzed with microcomputed tomography and histology; 8.6±1.4 μg BMP2 (22%) and 140±29 IU EPO (69.8%) bound to the scaffold and <1% BMP2 and 83% EPO was released in 7 days. Increased endothelial cell proliferation on EPO-adsorbed PCL discs indicated protein bioactivity. At 4 and 8 weeks, dual BMP2 and EPO delivery regenerated more bone (5.1±1.1 and 5.5±1.6 mm3) than BMP2 alone (3.8±1.1 and 4.3±1.7 mm3). BMP2 and EPO scaffolds had more ingrowth (1.4%±0.6%) in the outer module when compared with BMP2 (0.8%±0.3%) at 4 weeks. Dual delivery produced more dense cellular marrow, while BMP2 had more fatty marrow. Dual EPO and BMP2 delivery is a potential method to regenerate bone faster for prefabricated flaps. PMID:25809081

  5. Dual Delivery of EPO and BMP2 from a Novel Modular Poly-ɛ-Caprolactone Construct to Increase the Bone Formation in Prefabricated Bone Flaps.

    PubMed

    Patel, Janki Jayesh; Modes, Jane E; Flanagan, Colleen L; Krebsbach, Paul H; Edwards, Sean P; Hollister, Scott J

    2015-09-01

    Poly-ɛ-caprolactone (PCL) is a biocompatible polymer that has mechanical properties suitable for bone tissue engineering; however, it must be integrated with biologics to stimulate bone formation. Bone morphogenetic protein-2 (BMP2) delivered from PCL produces bone when implanted subcutaneously, and erythropoietin (EPO) works synergistically with BMP2. In this study, EPO and BMP2 are adsorbed separately on two 3D-printed PCL scaffold modules that are assembled for codelivery on a single scaffold structure. This assembled modular PCL scaffold with dual BMP2 and EPO delivery was shown to increase bone growth in an ectopic location when compared with BMP2 delivery along a replicate scaffold structure. EPO (200 IU/mL) and BMP2 (65 μg/mL) were adsorbed onto the outer and inner portions of a modular scaffold, respectively. Protein binding and release studies were first quantified. Subsequently, EPO+BMP2 and BMP2 scaffolds were implanted subcutaneously in mice for 4 and 8 weeks, and the regenerated bone was analyzed with microcomputed tomography and histology; 8.6±1.4 μg BMP2 (22%) and 140±29 IU EPO (69.8%) bound to the scaffold and <1% BMP2 and 83% EPO was released in 7 days. Increased endothelial cell proliferation on EPO-adsorbed PCL discs indicated protein bioactivity. At 4 and 8 weeks, dual BMP2 and EPO delivery regenerated more bone (5.1±1.1 and 5.5±1.6 mm(3)) than BMP2 alone (3.8±1.1 and 4.3±1.7 mm(3)). BMP2 and EPO scaffolds had more ingrowth (1.4%±0.6%) in the outer module when compared with BMP2 (0.8%±0.3%) at 4 weeks. Dual delivery produced more dense cellular marrow, while BMP2 had more fatty marrow. Dual EPO and BMP2 delivery is a potential method to regenerate bone faster for prefabricated flaps.

  6. Evaluating the oxysterol combination of 22(S)-hydroxycholesterol and 20(S)-hydroxycholesterol in periodontal regeneration using periodontal ligament stem cells and alveolar bone healing models.

    PubMed

    Lee, Jin-Sun; Kim, EunJi; Han, Seonggu; Kang, Kyung Lhi; Heo, Jung Sun

    2017-12-06

    Oxysterols, oxygenated by-products of cholesterol biosynthesis, play roles in various physiological and pathological systems. However, the effects of oxysterols on periodontal regeneration are unknown. This study investigated the effects of the specific oxysterol combination of 22(S)-hydroxycholesterol and 20(S)-hydroxycholesterol (SS) on the regeneration of periodontal tissues using in-vitro periodontal ligament stem cells (PDLSCs) and in-vivo models of alveolar bone defect. To evaluate the effects of the combined oxysterols on PDLSC biology, we studied the SS-induced osteogenic differentiation of PDLSCs by assessing alkaline phosphatase activity, intracellular calcium levels [Ca 2+ ] i , matrix mineralization, and osteogenic marker mRNA expression and protein levels. To verify the effect of oxysterols on alveolar bone regeneration, we employed tooth extraction bone defect models. Oxysterols increased the osteogenic activity of PDLSCs compared with the control group. The expression of liver X receptor (LXR) α and β, the nuclear receptors for oxysterols, and their target gene, ATP-binding cassette transporter A1 (ABCA1), increased significantly during osteogenesis. Oxysterols also increased protein levels of the hedgehog (Hh) receptor Smo and the transcription factor Gli1. We further confirmed the reciprocal reaction between the LXRs and Hh signaling. Transfection of both LXRα and LXRβ siRNAs decreased Smo and Gli1 protein levels. In contrast, the inhibition of Hh signaling attenuated the LXRα and LXRβ protein levels. Subsequently, SS-induced osteogenic activity of PDLSCs was suppressed by the inhibition of LXRs or Hh signaling. The application of SS also enhanced bone formation in the defect sites of in-vivo models, showing equivalent efficacy to recombinant human bone morphogenetic protein-2. These findings suggest that a specific combination of oxysterols promoted periodontal regeneration by regulating PDLSC activity and alveolar bone regeneration.

  7. Bone formation in vitro and in nude mice by human osteosarcoma cells.

    PubMed

    Ogose, A; Motoyama, T; Hotta, T; Watanabe, H; Takahashi, H E

    1995-01-01

    Osteosarcomas contain variable amounts of bony tissue, but the mechanism of bone formation by osteosarcoma is not well understood. While a number of cultured human osteosarcoma cell lines have been established, they are maintained by different media and differ qualitatively with regard to bone formation. We examined different media for their ability to support bone formation in vitro and found the alpha-modification of Eagle's minimal essential medium supplemented with beta glycerophosphate was best for this purpose, because it contained the proper calcium and phosphate concentrations. Subsequently, we compared seven human osteosarcoma cell lines under the same experimental conditions to clarify their ability to induce bone formation. NOS-1 cells most frequently exhibited features of bone formation in vitro and in nude mice. Collagen synthesis by tumour cells themselves seemed to be the most important factor for bone volume. However, even HuO9 cells, which lacked collagen synthesis and failed to form bone in vitro, successfully formed tumours containing bone in nude mice. Histological analysis of HuO9 cells in diffusion chambers implanted in nude mice and the findings of polymerase chain reaction indicated that the phenomenon was probably due to bone morphogenetic protein.

  8. The therapeutic effect of negative pressure in treating femoral head necrosis in rabbits.

    PubMed

    Zhang, Yin-gang; Wang, Xuezhi; Yang, Zhi; Zhang, Hong; Liu, Miao; Qiu, Yushen; Guo, Xiong

    2013-01-01

    Because negative pressure can stimulate vascular proliferation, improve blood circulation and promote osteogenic differentiation of bone marrow stromal cells, we investigated the therapeutic effect of negative pressure on femoral head necrosis (FHN) in a rabbit model. Animals were divided into four groups (n = 60/group): [1] model control, [2] core decompression, [3] negative pressure and [4] normal control groups. Histological investigation revealed that at 4 and 8 weeks postoperatively, improvements were observed in trabecular bone shape, empty lacunae and numbers of bone marrow hematopoietic cells and fat cells in the negative pressure group compared to the core decompression group. At week 8, there were no significant differences between the negative pressure and normal control groups. Immunohistochemistry staining revealed higher expression of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in the femoral heads in the negative pressure group compared with the core decompression group. Transmission electron microscopy revealed that cell organelles were further developed in the negative pressure group compared with the core decompression group. Microvascular ink staining revealed an increased number of bone marrow ink-stained blood vessels, a thicker vascular lumen and increased microvascular density in the negative pressure group relative to the core decompression group. Real-time polymerase chain reaction revealed that expression levels of both VEGF and BMP-2 were higher in the negative pressure group compared with the core decompression group. In summary, negative pressure has a therapeutic effect on FHN. This effect is superior to core decompression, indicating that negative pressure is a potentially valuable method for treating early FHN.

  9. The Therapeutic Effect of Negative Pressure in Treating Femoral Head Necrosis in Rabbits

    PubMed Central

    Zhang, Yin-gang; Wang, Xuezhi; Yang, Zhi; Zhang, Hong; Liu, Miao; Qiu, Yushen; Guo, Xiong

    2013-01-01

    Because negative pressure can stimulate vascular proliferation, improve blood circulation and promote osteogenic differentiation of bone marrow stromal cells, we investigated the therapeutic effect of negative pressure on femoral head necrosis (FHN) in a rabbit model. Animals were divided into four groups (n = 60/group): [1] model control, [2] core decompression, [3] negative pressure and [4] normal control groups. Histological investigation revealed that at 4 and 8 weeks postoperatively, improvements were observed in trabecular bone shape, empty lacunae and numbers of bone marrow hematopoietic cells and fat cells in the negative pressure group compared to the core decompression group. At week 8, there were no significant differences between the negative pressure and normal control groups. Immunohistochemistry staining revealed higher expression of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-2 (BMP-2) in the femoral heads in the negative pressure group compared with the core decompression group. Transmission electron microscopy revealed that cell organelles were further developed in the negative pressure group compared with the core decompression group. Microvascular ink staining revealed an increased number of bone marrow ink-stained blood vessels, a thicker vascular lumen and increased microvascular density in the negative pressure group relative to the core decompression group. Real-time polymerase chain reaction revealed that expression levels of both VEGF and BMP-2 were higher in the negative pressure group compared with the core decompression group. In summary, negative pressure has a therapeutic effect on FHN. This effect is superior to core decompression, indicating that negative pressure is a potentially valuable method for treating early FHN. PMID:23383276

  10. Bone mesenchymal stem cells co-expressing VEGF and BMP-6 genes to combat avascular necrosis of the femoral head

    PubMed Central

    Liao, Hongxing; Zhong, Zhixiong; Liu, Zhanliang; Li, Liangping; Ling, Zemin; Zou, Xuenong

    2018-01-01

    The aim of the present study was to investigate the potential of bone mesenchymal stem cells (BMSCs) treated with a combination of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-6 (BMP-6) genes for the treatment of avascular necrosis of the femoral head (ANFH). Rat BMSCs were isolated and purified using a density gradient centrifugation method. The purity and characteristics of the BMSCs were detected by cell surface antigens identification using flow cytometry. The experimental groups were administered with one of the following adeno-associated virus (AAV) vector constructs: AAV-green fluorescent protein (AAV-GFP), AAV-BMP-6, AAV-VEGF or AAV-VEGF-BMP-6. The expression of VEGF and BMP-6 was detected by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA assays. The effects of VEGF and BMP-6 on BMSCs were evaluated by angiogenic and osteogenic assays. The transfected BMSCs were combined with a biomimetic synthetic scaffold poly lactide-co-glycolide (PLAGA) and they were then subcutaneously implanted into nude mice. After four weeks, the implants were analyzed with histology and subsequent immunostaining to evaluate the effects of BMSCs on blood vessel and bone formation in vivo. In the AAV-VEGF-BMP-6 group, the expression levels of VEGF and BMP-6 were significantly increased and human umbilical vein endothelial cells tube formation was significantly enhanced compared with other groups. Capillaries and bone formation in the AAV-VEGF-BMP-6 group was significantly higher compared with the other groups. The results of the present study suggest that BMSCs expressing both VEGF and BMP-6 induce an increase in blood vessels and bone formation, which provides theoretical support for ANFH gene therapy. PMID:29399103

  11. Bone mesenchymal stem cells co-expressing VEGF and BMP-6 genes to combat avascular necrosis of the femoral head.

    PubMed

    Liao, Hongxing; Zhong, Zhixiong; Liu, Zhanliang; Li, Liangping; Ling, Zemin; Zou, Xuenong

    2018-01-01

    The aim of the present study was to investigate the potential of bone mesenchymal stem cells (BMSCs) treated with a combination of vascular endothelial growth factor (VEGF) and bone morphogenetic protein-6 (BMP-6) genes for the treatment of avascular necrosis of the femoral head (ANFH). Rat BMSCs were isolated and purified using a density gradient centrifugation method. The purity and characteristics of the BMSCs were detected by cell surface antigens identification using flow cytometry. The experimental groups were administered with one of the following adeno-associated virus (AAV) vector constructs: AAV-green fluorescent protein (AAV-GFP), AAV-BMP-6, AAV-VEGF or AAV-VEGF-BMP-6. The expression of VEGF and BMP-6 was detected by reverse transcription-quantitative polymerase chain reaction, western blotting and ELISA assays. The effects of VEGF and BMP-6 on BMSCs were evaluated by angiogenic and osteogenic assays. The transfected BMSCs were combined with a biomimetic synthetic scaffold poly lactide-co-glycolide (PLAGA) and they were then subcutaneously implanted into nude mice. After four weeks, the implants were analyzed with histology and subsequent immunostaining to evaluate the effects of BMSCs on blood vessel and bone formation in vivo . In the AAV-VEGF-BMP-6 group, the expression levels of VEGF and BMP-6 were significantly increased and human umbilical vein endothelial cells tube formation was significantly enhanced compared with other groups. Capillaries and bone formation in the AAV-VEGF-BMP-6 group was significantly higher compared with the other groups. The results of the present study suggest that BMSCs expressing both VEGF and BMP-6 induce an increase in blood vessels and bone formation, which provides theoretical support for ANFH gene therapy.

  12. Smad4 controls bone homeostasis through regulation of osteoblast/osteocyte viability.

    PubMed

    Moon, Young Jae; Yun, Chi-Young; Choi, Hwajung; Ka, Sun-O; Kim, Jung Ryul; Park, Byung-Hyun; Cho, Eui-Sic

    2016-09-02

    Regulation of osteoblast and osteocyte viability is essential for bone homeostasis. Smad4, a major transducer of bone morphogenetic protein and transforming growth factor-β signaling pathways, regulates apoptosis in various cell types through a mitochondrial pathway. However, it remains poorly understood whether Smad4 is necessary for the regulation of osteoblast and osteocyte viability. In this study, we analyzed Smad4Δ(Os) mice, in which Smad4 was subjected to tissue-specific disruption under the control of the 2.3-kb Col1a1 promoter, to understand the functional significance of Smad4 in regulating osteoblast/osteocyte viability during bone formation and remodeling. Smad4Δ(Os) mice showed a significant increase in osteoblast number and osteocyte density in the trabecular and cortical regions of the femur, whereas osteoclast activity was significantly decreased. The proliferation of osteoblasts/osteocytes did not alter, as shown by measuring 5'-bromo-2'deoxyuridine incorporation. By contrast, the percentage of TUNEL-positive cells decreased, together with a decrease in the Bax/Bcl-2 ratio and in the proteolytic cleavage of caspase 3, in Smad4Δ(Os) mice. Apoptosis in isolated calvaria cells from Smad4Δ(Os) mice decreased after differentiation, which was consistent with the results of the TUNEL assay and western blotting in Smad4Δ(Os) mice. Conversely, osteoblast cells overexpressing Smad4 showed increased apoptosis. In an apoptosis induction model of Smad4Δ(Os) mice, osteoblasts/osteocytes were more resistant to apoptosis than were control cells, and, consequently, bone remodeling was attenuated. These findings indicate that Smad4 has a significant role in regulating osteoblast/osteocyte viability and therefore controls bone homeostasis.

  13. Gene expression analysis in calcific tendinopathy of the rotator cuff.

    PubMed

    Oliva, F; Barisani, D; Grasso, A; Maffulli, N

    2011-06-20

    We evaluated the expression of several genes involved in tissue remodelling and bone development in patients with calcific tendinopathy of the rotator cuff. Biopsies from calcified and non-calcified areas were obtained from 10 patients (8 women and 2 men; average age: 55 years; range: 40-68) with calcific tendinopathy of the rotator cuff. To evaluate the expression of selected genes, RNA extraction, cDNA synthesis and quantitative polymerase chain reaction (PCR) were performed. A significantly increased expression of tissue transglutaminase (tTG)2 and its substrate, osteopontin, was detected in the calcific areas compared to the levels observed in the normal tissue from the same subject with calcific tendinopathy, whereas a modest increase was observed for catepsin K. There was also a significant decrease in mRNA expression of Bone Morphogenetic Protein (BMP)4 and BMP6 in the calcific area. BMP-2, collagen V and vascular endothelial growth factor (VEGF) did not show significant differences. Collagen X and matrix metalloproteinase (MMP)-9 were not detectable. A variation in expression of these genes could be characteristic of this form tendinopathy, since an increased level of these genes has not been detected in other forms of tendon lesions.

  14. A synthetic compound that potentiates bone morphogenetic protein-2-induced transdifferentiation of myoblasts into the osteoblastic phenotype

    PubMed Central

    Kato, Satoshi; Tomita, Katsuro; Titus, Louisa; Boden, Scott D.

    2011-01-01

    There is an urgent need to develop methods that lower costs of using recombinant human bone morphogenetic proteins (BMPs) to promote bone induction. In this study, we demonstrate the osteogenic effect of a low-molecular weight compound, SVAK-12, that potentiated the effects of BMP-2 in inducing transdifferentiation of C2C12 myoblasts into the osteoblastic phenotype. Here, we report a specific compound, SVAK-12, which was selected based on in silico screenings of small-molecule databases using the homology modeled interaction motif of Smurf1-WW2 domain. The enhancement of BMP-2 activity by SVAK-12 was characterized by evaluating a BMP-specific reporter activity and by monitoring the BMP-2-induced expression of mRNA for osteocalcin and alkaline phosphatase (ALP), which are widely accepted marker genes of osteoblast differentiation. Finally, we confirmed these results by also measuring the enhancement of BMP-2-induced activity of ALP. Smurf1 is an E3 ligase that targets osteogenic Smads for ubiquitin-mediated proteasomal degradation. Smurf1 is an interesting potential target to enhance bone formation based on the positive effects on bone of proteins that block Smurf1-binding to Smad targets or in Smurf1−/− knockout mice. Since Smads bind Smurf1 via its WW2 domain, we performed in silico screening to identify compounds that might interact with the Smurf1-WW2 domain. We recently reported the activity of a compound, SVAK-3. However, SVAK-3, while exhibiting BMP-potentiating activity, was not stable and thus warranted a new search for a more stable and efficacious compound among a selected group of candidates. In addition to being more stable, SVAK-12 exhibited a dose-dependent activity in inducing osteoblastic differentiation of myoblastic C2C12 cells even when multiple markers of the osteoblastic phenotype were parallelly monitored. PMID:21110071

  15. A synthetic compound that potentiates bone morphogenetic protein-2-induced transdifferentiation of myoblasts into the osteoblastic phenotype.

    PubMed

    Kato, Satoshi; Sangadala, Sreedhara; Tomita, Katsuro; Titus, Louisa; Boden, Scott D

    2011-03-01

    There is an urgent need to develop methods that lower costs of using recombinant human bone morphogenetic proteins (BMPs) to promote bone induction. In this study, we demonstrate the osteogenic effect of a low-molecular weight compound, SVAK-12, that potentiated the effects of BMP-2 in inducing transdifferentiation of C2C12 myoblasts into the osteoblastic phenotype. Here, we report a specific compound, SVAK-12, which was selected based on in silico screenings of small-molecule databases using the homology modeled interaction motif of Smurf1-WW2 domain. The enhancement of BMP-2 activity by SVAK-12 was characterized by evaluating a BMP-specific reporter activity and by monitoring the BMP-2-induced expression of mRNA for osteocalcin and alkaline phosphatase (ALP), which are widely accepted marker genes of osteoblast differentiation. Finally, we confirmed these results by also measuring the enhancement of BMP-2-induced activity of ALP. Smurf1 is an E3 ligase that targets osteogenic Smads for ubiquitin-mediated proteasomal degradation. Smurf1 is an interesting potential target to enhance bone formation based on the positive effects on bone of proteins that block Smurf1-binding to Smad targets or in Smurf1-/- knockout mice. Since Smads bind Smurf1 via its WW2 domain, we performed in silico screening to identify compounds that might interact with the Smurf1-WW2 domain. We recently reported the activity of a compound, SVAK-3. However, SVAK-3, while exhibiting BMP-potentiating activity, was not stable and thus warranted a new search for a more stable and efficacious compound among a selected group of candidates. In addition to being more stable, SVAK-12 exhibited a dose-dependent activity in inducing osteoblastic differentiation of myoblastic C2C12 cells even when multiple markers of the osteoblastic phenotype were parallelly monitored.

  16. Bone healing in 2016

    PubMed Central

    Buza, John A.; Einhorn, Thomas

    2016-01-01

    Summary Delayed fracture healing and nonunion occurs in up to 5–10% of all fractures, and can present a challenging clinical scenario for the treating physician. Methods for the enhancement of skeletal repair may benefit patients that are at risk of, or have experienced, delayed healing or nonunion. These methods can be categorized into either physical stimulation therapies or biological therapies. Physical stimulation therapies include electrical stimulation, low-intensity pulsed ultrasonography, or extracorporeal shock wave therapy. Biological therapies can be further classified into local or systemic therapy based on the method of delivery. Local methods include autologous bone marrow, autologous bone graft, fibroblast growth factor-2, platelet-rich plasma, platelet-derived growth factor, and bone morphogenetic proteins. Systemic therapies include parathyroid hormone and bisphosphonates. This article reviews the current applications and supporting evidence for the use of these therapies in the enhancement of fracture healing. PMID:27920804

  17. Tenascin-W inhibits proliferation and differentiation of preosteoblasts during endochondral bone formation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kimura, Hiroaki; Akiyama, Haruhiko; Nakamura, Takashi

    We identified a cDNA encoding mouse Tenascin-W (TN-W) upregulated by bone morphogenetic protein (Bmp)2 in ATDC5 osteo-chondroprogenitors. In adult mice, TN-W was markedly expressed in bone. In mouse embryos, during endochondral bone formation TN-W was localized in perichondrium/periosteum, but not in trabecular and cortical bones. During bone fracture repair, cells in the newly formed perichondrium/periosteum surrounding the cartilaginous callus expressed TN-W. Furthermore, TN-W was detectable in perichondrium/periosteum of Runx2-null and Osterix-null embryos, indicating that TN-W is expressed in preosteoblasts. In CFU-F and -O cells, TN-W had no effect on initiation of osteogenesis of bone marrow cells, and in MC3T3-E1 osteoblasticmore » cells TN-W inhibited cell proliferation and Col1a1 expression. In addition, TN-W suppressed canonical Wnt signaling which stimulates osteoblastic differentiation. Our results indicate that TN-W is a novel marker of preosteoblasts in early stage of osteogenesis, and that TN-W inhibits cell proliferation and differentiation of preosteoblasts mediated by canonical Wnt signaling.« less

  18. Dual Role of Jun N-Terminal Kinase Activity in Bone Morphogenetic Protein-Mediated Drosophila Ventral Head Development.

    PubMed

    Park, Sung Yeon; Stultz, Brian G; Hursh, Deborah A

    2015-12-01

    The Drosophila bone morphogenetic protein encoded by decapentaplegic (dpp) controls ventral head morphogenesis by expression in the head primordia, eye-antennal imaginal discs. These are epithelial sacs made of two layers: columnar disc proper cells and squamous cells of the peripodial epithelium. dpp expression related to head formation occurs in the peripodial epithelium; cis-regulatory mutations disrupting this expression display defects in sensory vibrissae, rostral membrane, gena, and maxillary palps. Here we document that disruption of this dpp expression causes apoptosis in peripodial cells and underlying disc proper cells. We further show that peripodial Dpp acts directly on the disc proper, indicating that Dpp must cross the disc lumen to act. We demonstrate that palp defects are mechanistically separable from the other mutant phenotypes; both are affected by the c-Jun N-terminal kinase pathway but in opposite ways. Slight reduction of both Jun N-terminal kinase and Dpp activity in peripodial cells causes stronger vibrissae, rostral membrane, and gena defects than Dpp alone; additionally, strong reduction of Jun N-terminal kinase activity alone causes identical defects. A more severe reduction of dpp results in similar vibrissae, rostral membrane, and gena defects, but also causes mutant maxillary palps. This latter defect is correlated with increased peripodial Jun N-terminal kinase activity and can be caused solely by ectopic activation of Jun N-terminal kinase. We conclude that formation of sensory vibrissae, rostral membrane, and gena tissue in head morphogenesis requires the action of Jun N-terminal kinase in peripodial cells, while excessive Jun N-terminal kinase signaling in these same cells inhibits the formation of maxillary palps. Copyright © 2015 by the Genetics Society of America.

  19. Bone morphogenetic protein-binding endothelial regulator of liver sinusoidal endothelial cells induces iron overload in a fatty liver mouse model.

    PubMed

    Hasebe, Takumu; Tanaka, Hiroki; Sawada, Koji; Nakajima, Shunsuke; Ohtake, Takaaki; Fujiya, Mikihiro; Kohgo, Yutaka

    2017-03-01

    Non-alcoholic fatty liver disease (NAFLD) is frequently accompanied by iron overload. However, because of the complex hepcidin-regulating molecules, the molecular mechanism underlying iron overload remains unknown. To identify the key molecule involved in NAFLD-associated iron dysregulation, we performed whole-RNA sequencing on the livers of obese mice. Male C57BL/6 mice were fed a regular or high-fat diet for 16 or 48 weeks. Internal iron was evaluated by plasma iron, ferritin or hepatic iron content. Whole-RNA sequencing was performed by transcriptome analysis using semiconductor high-throughput sequencer. Mouse liver tissues or isolated hepatocytes and sinusoidal endothelial cells were used to assess the expression of iron-regulating molecules. Mice fed a high-fat diet for 16 weeks showed excess iron accumulation. Longer exposure to a high-fat diet increased hepatic fibrosis and intrahepatic iron accumulation. A pathway analysis of the sequencing data showed that several inflammatory pathways, including bone morphogenetic protein (BMP)-SMAD signaling, were significantly affected. Sequencing analysis showed 2314 altered genes, including decreased mRNA expression of the hepcidin-coding gene Hamp. Hepcidin protein expression and SMAD phosphorylation, which induces Hamp, were found to be reduced. The expression of BMP-binding endothelial regulator (BMPER), which inhibits BMP-SMAD signaling by binding BMP extracellularly, was up-regulated in fatty livers. In addition, immunohistochemical and cell isolation analyses showed that BMPER was primarily expressed in the liver sinusoidal endothelial cells (LSECs) rather than hepatocytes. BMPER secretion by LSECs inhibits BMP-SMAD signaling in hepatocytes and further reduces hepcidin protein expression. These intrahepatic molecular interactions suggest a novel molecular basis of iron overload in NAFLD.

  20. Alk2/ACVR1 and Alk3/BMPR1A Provide Essential Function for Bone Morphogenetic Protein-Induced Retinal Angiogenesis.

    PubMed

    Lee, Heon-Woo; Chong, Diana C; Ola, Roxana; Dunworth, William P; Meadows, Stryder; Ka, Jun; Kaartinen, Vesa M; Qyang, Yibing; Cleaver, Ondine; Bautch, Victoria L; Eichmann, Anne; Jin, Suk-Won

    2017-04-01

    Increasing evidence suggests that bone morphogenetic protein (BMP) signaling regulates angiogenesis. Here, we aimed to define the function of BMP receptors in regulating early postnatal angiogenesis by analysis of inducible, endothelial-specific deletion of the BMP receptor components Bmpr2 (BMP type 2 receptor), Alk1 (activin receptor-like kinase 1), Alk2 , and Alk3 in mouse retinal vessels. Expression analysis of several BMP ligands showed that proangiogenic BMP ligands are highly expressed in postnatal retinas. Consistently, BMP receptors are also strongly expressed in retina with a distinct pattern. To assess the function of BMP signaling in retinal angiogenesis, we first generated mice carrying an endothelial-specific inducible deletion of Bmpr2 . Postnatal deletion of Bmpr2 in endothelial cells substantially decreased the number of angiogenic sprouts at the vascular front and branch points behind the front, leading to attenuated radial expansion. To identify critical BMPR1s (BMP type 1 receptors) associated with BMPR2 in retinal angiogenesis, we generated endothelial-specific inducible deletion of 3 BMPR1s abundantly expressed in endothelial cells and analyzed the respective phenotypes. Among these, endothelial-specific deletion of either Alk2 / acvr1 or Alk3 / Bmpr1a caused a delay in radial expansion, reminiscent of vascular defects associated with postnatal endothelial-specific deletion of BMPR2, suggesting that ALK2/ACVR1 and ALK3/BMPR1A are likely to be the critical BMPR1s necessary for proangiogenic BMP signaling in retinal vessels. Our data identify BMP signaling mediated by coordination of ALK2/ACVR1, ALK3/BMPR1A, and BMPR2 as an essential proangiogenic cue for retinal vessels. © 2017 The Authors.

  1. Alk2/ACVR1 and Alk3/BMPR1A Provide Essential Function for Bone Morphogenetic Protein Induced Retinal Angiogenesis

    PubMed Central

    Lee, Heon-Woo; Chong, Diana C.; Ola, Roxana; Dunworth, William P.; Meadows, Stryder; Ka, Jun; Kaartinen, Vesa M.; Qyang, Yibing; Cleaver, Ondine; Bautch, Victoria L.; Eichmann, Anne; Jin, Suk-Won

    2017-01-01

    Objective Increasing evidence suggests that Bone Morphogenetic Protein (BMP) signaling regulates angiogenesis. Here, we aimed to define the function of BMP receptors in regulating early post-natal angiogenesis by analysis of inducible, endothelial specific deletion of the BMP receptor components Bmpr2, Alk1, Alk2 and Alk3 in mouse retinal vessels. Approach and Results Expression analysis of several BMP ligands showed that pro-angiogenic BMP ligands are highly expressed in postnatal retinas. Consistently, BMP receptors are also strongly expressed in retina with a distinct pattern. To assess the function of BMP signaling in retinal angiogenesis, we first generated mice carrying an endothelial-specific inducible deletion of BMP Type 2 receptor (Bmpr2). Postnatal deletion of Bmpr2 in endothelial cells substantially decreased the number of angiogenic sprouts at the vascular front and branchpoints behind the front, leading to attenuated radial expansion. To identify critical BMPR1s associated with BMPR2 in retinal angiogenesis, we generated endothelial-specific inducible deletion of three BMPR1s abundantly expressed in endothelial cells and analyzed the respective phenotypes. Among these, endothelial specific deletion of either Alk2/acvr1 or Alk3/Bmpr1a caused a delay in radial expansion, reminiscent of vascular defects associated with postnatal endothelial specific deletion of BMPR2, suggesting that ALK2/ACVR1 and ALK3/BMPR1A are likely to be the critical BMPR1s necessary for pro-angiogenic BMP signaling in retinal vessels. Conclusions Our data identify BMP signaling mediated by coordination of ALK2/ACVR1, ALK3/BMPR1A, and BMPR2 as an essential pro-angiogenic cue for retinal vessels. PMID:28232325

  2. The effect of recombinant bone morphogenetic protein-2 in revision tibiotalocalcaneal arthrodesis: utilization of the Retrograde Arthrodesis Intramedullary Nail database.

    PubMed

    DeVries, J George; Nguyen, Minh; Berlet, Gregory C; Hyer, Christopher F

    2012-01-01

    The use of bone morphogenetic protein-2 (BMP-2) has been recommended for high-risk fusions and nonunion. Patients undergoing revisional tibiotalocalcaneal (TTC) arthrodesis via a retrograde arthrodesis nail to evaluate the influence of BMP-2 on rate of fusion in this high-risk population are presented. A retrospective chart and radiographic review were performed on 23 patients with failed prior fusion attempts at the ankle treated with retrograde intramedullary nailing. Sixteen patients were treated without BMP-2 (None group) and 7 were treated with BMP-2 (BMP group). The primary and secondary end-points were successful fusion, and time to fusion, respectively, with a variety of variables evaluated for influence. Other than the use of BMP-2, there were no statistical differences in the patient population. Overall, 11 of 16 ankles (68.8%) in the None group and 5 of 7 ankles (71.4%) in the BMP group resulted in a stable, functional limb. Rate of complication was similar between the 2 groups (p > .05). Time to radiographic ankle union was 115.2 and 184.0 days in the None and BMP groups (p > .05). The effect of BMP-2 on revisional TTC fusions with retrograde nails is reported here. The overall result as a stable, functional limb was 69.6%, which suggests that revision surgery in this high-risk population is a reasonable consideration. Even though this study was unable to demonstrate statistically significant differences, biologic augmentation with BMP-2 did not increase the complication rate and showed a slightly enhanced salvage rate for revision TTC fusions with an intramedullary nail. Copyright © 2012 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  3. Nonsyndromic cleft lip with or without cleft palate: Increased burden of rare variants within Gremlin-1, a component of the bone morphogenetic protein 4 pathway.

    PubMed

    Al Chawa, Taofik; Ludwig, Kerstin U; Fier, Heide; Pötzsch, Bernd; Reich, Rudolf H; Schmidt, Gül; Braumann, Bert; Daratsianos, Nikolaos; Böhmer, Anne C; Schuencke, Hannah; Alblas, Margrieta; Fricker, Nadine; Hoffmann, Per; Knapp, Michael; Lange, Christoph; Nöthen, Markus M; Mangold, Elisabeth

    2014-06-01

    The genes Gremlin-1 (GREM1) and Noggin (NOG) are components of the bone morphogenetic protein 4 pathway, which has been implicated in craniofacial development. Both genes map to recently identified susceptibility loci (chromosomal region 15q13, 17q22) for nonsyndromic cleft lip with or without cleft palate (nsCL/P). The aim of the present study was to determine whether rare variants in either gene are implicated in nsCL/P etiology. The complete coding regions, untranslated regions, and splice sites of GREM1 and NOG were sequenced in 96 nsCL/P patients and 96 controls of Central European ethnicity. Three burden and four nonburden tests were performed. Statistically significant results were followed up in a second case-control sample (n = 96, respectively). For rare variants observed in cases, segregation analyses were performed. In NOG, four rare sequence variants (minor allele frequency < 1%) were identified. Here, burden and nonburden analyses generated nonsignificant results. In GREM1, 33 variants were identified, 15 of which were rare. Of these, five were novel. Significant p-values were generated in three nonburden analyses. Segregation analyses revealed incomplete penetrance for all variants investigated. Our study did not provide support for NOG being the causal gene at 17q22. However, the observation of a significant excess of rare variants in GREM1 supports the hypothesis that this is the causal gene at chr. 15q13. Because no single causal variant was identified, future sequencing analyses of GREM1 should involve larger samples and the investigation of regulatory elements. © 2014 Wiley Periodicals, Inc.

  4. Haplotype-based gene-gene interaction of bone morphogenetic protein 4 and interferon regulatory factor 6 in the etiology of non-syndromic cleft lip with or without cleft palate in a Chilean population.

    PubMed

    Blanco, Rafael; Colombo, Alicia; Pardo, Rosa; Suazo, José

    2017-04-01

    Non-syndromic cleft lip with or without cleft palate (NSCL/P) is the most common craniofacial birth defect in humans, the etiology of which can be dependent on the interactions of multiple genes. We previously reported haplotype associations for polymorphic variants of interferon regulatory factor 6 (IRF6), msh homeobox 1 (MSX1), bone morphogenetic protein 4 (BMP4), and transforming growth factor beta 3 (TGFB3) in Chile. Here, we analyzed the haplotype-based gene-gene interaction for markers of these genes and NSCL/P risk in the Chilean population. We genotyped 15 single nucleoptide polymorphisms (SNPs) in 152 Chilean patients and 164 controls. Linkage disequilibrium (LD) blocks were determined using the Haploview software, and phase reconstruction was performed by the Phase program. Haplotype-based interactions were evaluated using the multifactor dimensionality reduction (MDR) method. We detected two LD blocks composed of two SNPs from BMP4 (Block 1) and three SNPs from IRF6 (Block 2). Although MDR showed no statistical significance for the global interaction model involving these blocks, we found four combinations conferring a statistically significantly increased NSCL/P risk (Block 1-Block 2): T-T/T-G C-G-T/G-A-T; T-T/T-G C-G-C/C-G-C; T-T/T-G G-A-T/G-A-T; and T-T/C-G G-A-T/G-A-T. These findings may reflect the presence of a genomic region containing potential causal variants interacting in the etiology of NSCL/P and may contribute to disentangling the complex etiology of this birth defect. © 2017 Eur J Oral Sci.

  5. Recombinant human bone morphogenetic protein-2-induced radiculitis in elective minimally invasive transforaminal lumbar interbody fusions: a series review.

    PubMed

    Mindea, Stefan A; Shih, Patrick; Song, John K

    2009-06-15

    Retrospective single center analysis. The purpose of our study is to quantify the development of a postoperative radiculitis in our minimally invasive transforaminal lumbar interbody fusion patient population. The application of recombinant human Bone Morphogenetic Protein-2 (BMP) in spinal surgery has allowed for greater success in spinal fusions. This has led to the FDA approving its use in anterior lumbar interbody fusion. However, its well-recognized benefits have generated its "off-label" use in the cervical, thoracic, and lumbar spine. Despite its benefits, the adverse effects of its inflammatory properties are just starting to get recognized. Some clear adverse reactions have been documented in the literature in the cervical spine. However, we feel that these inflammatory properties may be present in the lumbar spine as well. We performed a retrospective chart review of 43 patients who had undergone a minimally invasive transforaminal lumbar interbody fusions. Thirty-five of these patients had BMP and 8 patients did not have BMP. We documented whether there was a preoperative radiculopathy present and whether a radiculopathy was present postoperative. We reviewed radiographic postoperative imaging to establish a structural cause for any radiculopathy. If new or increasing radicular symptoms were present, we attempted to assess the duration of these symptoms. Our analysis, showed that 0 of the 8 patients of the non-BMP group had new radicular symptoms that were not attributed to structural causes. In the BMP group, 4 of the 35 patients (11.4%) had new radicular symptoms without structural etiology. Our analysis suggest that patients undergoing minimally invasive transforaminal lumbar interbody fusions procedures have a higher incidence of developing new radicular symptoms that could be attributed to BMP.

  6. Recent Insights into the Regulation of the Growth Plate

    PubMed Central

    Lui, Julian C.; Nilsson, Ola; Baron, Jeffrey

    2014-01-01

    For most bones, elongation is driven primarily by chondrogenesis at the growth plates. This process results from chondrocyte proliferation, hypertrophy, and extracellular matrix secretion and is carefully orchestrated by complex networks of local paracrine factors and modulated by endocrine factors. We review here recent advances in the understanding of growth plate physiology. These advances include new approaches to study expression patterns of large numbers of genes in the growth plate, using microdissection followed by microarray. This approach has been combined with genome-wide association studies to provide insights into the regulation of the human growth plate. We also review recent studies elucidating the roles of bone morphogenetic proteins, fibroblast growth factors, C-type natriuretic peptide, and suppressor of cytokine signaling in the local regulation of growth plate chondrogenesis and longitudinal bone growth. PMID:24740736

  7. The effect of atorvastatin, 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor (HMG-CoA), on the prevention of osteoporosis in ovariectomized rabbits.

    PubMed

    Zhou, Huan; Xie, Yunqiu; Baloch, Zulqarnain; Shi, Qingping; Huo, Qiang; Ma, Tao

    2017-05-01

    Osteoporosis is a most frequent systemic skeletal disease characterized as low bone mineral density and microarchitectural deterioration of bone tissue, resulting in increased bone fragility and fracture risk. Although several drugs such as bisphosphonates, estrogen replacement treatment, and selective estrogen receptor modulators have been used to treat osteoporosis, all these are not the ideal drugs because of insufficient curative ability and adverse side effects. Recently, atorvastatin has ordinarily been prescribed as an anti-hyperlipidemia drug, not as an anti-osteoporosis drug. However, its clinical outcome and potential treatment mechanism are still unclear. In this study, the bilateral ovariectomy of rabbits was duplicated to develop osteoporosis animal model. The effect of atorvastatin on in vivo was determined, and the functional mechanism was studied in vitro after the curative effect was explored. Atorvastatin was observed to significantly increase the mechanical parameters such as maximum load, stiffness, and energy-absorbing capacity, and it improved the microarchitecture. The anti-osteoporosis activity of atorvastatin may be the result of the promotion of differentiation of osteoblasts by inducing synthesis of vascular endothelial growth factor, bone morphogenetic protein 2 (BMP2), core-binding factor alpha 1 (CBFα1), and inhibition of osteoclast formation through the osteoprotegerin (OPG)-receptor activator for the nuclear factor κB ligand (RANKL) system. Our study observations give reliable experimental evidence for clinical application of atorvastatin to treat the disorder of osteoporosis.

  8. Dephosphorylation of the linker regions of Smad1 and Smad2/3 by small C-terminal domain phosphatases has distinct outcomes for bone morphogenetic protein and transforming growth factor-beta pathways.

    PubMed

    Sapkota, Gopal; Knockaert, Marie; Alarcón, Claudio; Montalvo, Ermelinda; Brivanlou, Ali H; Massagué, Joan

    2006-12-29

    Smad proteins transduce bone morphogenetic protein (BMP) and transforming growth factor-beta (TGFbeta) signals upon phosphorylation of their C-terminal SXS motif by receptor kinases. The activity of Smad1 in the BMP pathway and Smad2/3 in the TGFbeta pathway is restricted by pathway cross-talk and feedback through protein kinases, including MAPK, CDK2/4, p38MAPK, JNK, and others. These kinases phosphorylate Smads 1-3 at the region that links the N-terminal DNA-binding domain and the C-terminal transcriptional domain. Phosphatases that dephosphorylate the linker region are therefore likely to play an integral part in the regulation of Smad activity. We reported previously that small C-terminal domain phosphatases 1, 2, and 3 (SCP1-3) dephosphorylate Smad1 C-terminal tail, thereby attenuating BMP signaling. Here we provide evidence that SCP1-3 also dephosphorylate the linker regions of Smad1 and Smad2/3 in vitro, in mammalian cells and in Xenopus embryos. Overexpression of SCP 1, 2, or 3 decreased linker phosphorylation of Smads 1, 2 and 3. Moreover, RNA interference-mediated knockdown of SCP1/2 increased the BMP-dependent phosphorylation of the Smad1 linker region as well as the C terminus. In contrast, SCP1/2 knockdown increased the TGFbeta-dependent linker phosphorylation of Smad2/3 but not the C-terminal phosphorylation. Consequently, SCP1/2 knockdown inhibited TGFbeta transcriptional responses, but it enhanced BMP transcriptional responses. Thus, by dephosphorylating Smad2/3 at the linker (inhibitory) but not the C-terminal (activating) site, the SCPs enhance TGFbeta signaling, and by dephosphorylating Smad1 at both sites, the SCPs reset Smad1 to the basal unphosphorylated state.

  9. [In vitro differentiation of synovial-derived mesenchymal stem cells infected by adenovirus vector mediated by bone morphogenetic protein 2/7 genes into fibrocartilage cells in rabbits].

    PubMed

    Fu, Peiliang; Zhang, Lei; Wu, Haishan; Cong, Ruijun; Chen, Song; Ding, Zheru; Hu, Kaimen

    2013-03-01

    To investigate the feasibility of rabbit synovial-derived mesenchymal stem cells (SMSCs) differentiating into fibrocartilage cells by the recombinant adenovirus vector mediated by bone morphogenetic protein 2/7 (BMP-2/7) genes in vitro. SMSCs were isolated and purified from 3-month-old New Zealand white rabbits [male or female, weighing (2.1 +/- 0.3) kg]; the morphology was observed; the cells were identified with immunocytological fluorescent staining, flow cytometry, and cell cycles. The adipogenic, osteogenic, and chondrogenic differentiations were detected. The recombinant plasmid of pAdTrack-BMP-2-internal ribosome entry site (IRES)-BMP-7 was constructed and then was used to infect SMSCs. The cell DNA content and the oncogenicity were tested to determine the safety. Then infected SMSCs were cultured in incomplete chondrogenic medium in vitro. Chondrogenic differentiation of infected SMSCs was detected by RT-PCR, immunofluorescent staining, and toluidine blue staining. SMSCs expressed surface markers of stem cells, and had multi-directional potential. The transfection efficiency of SMSCs infected by recombinant plasmid of pAdTrack-BMP-2-IRES-BMP-7 was about 70%. The safety results showed that infected SMSCs had normal double time, normal chromosome number, and normal DNA content and had no oncogenicity. At 21 days after cultured in incomplete chondrocyte medium, RT-PCR results showed SMSCs had increased expressions of collegan type I and collegan type II, particularly collegan type II; the expressions of RhoA and Sox-9 increased obviously. Immunofluorescent staining and toluidine blue staining showed differentiation of SMSCs into fibrocartilage cells. It is safe to use pAdTrack-BMP-2-IRES-BMP-7 for infecting SMSCs. SMSCs infected by pAdTrack-BMP-2-IRES-BMP-7 can differentiate into fibrocartilage cells spontaneously in vitro.

  10. Bone Morphogenetic Protein 3 Controls Insulin Gene Expression and Is Down-regulated in INS-1 Cells Inducibly Expressing a Hepatocyte Nuclear Factor 1A–Maturity-onset Diabetes of the Young Mutation*

    PubMed Central

    Bonner, Caroline; Farrelly, Angela M.; Concannon, Caoimhín G.; Dussmann, Heiko; Baquié, Mathurin; Virard, Isabelle; Wobser, Hella; Kögel, Donat; Wollheim, Claes B.; Rupnik, Marjan; Byrne, Maria M.; König, Hans-Georg; Prehn, Jochen H. M.

    2011-01-01

    Inactivating mutations in the transcription factor hepatocyte nuclear factor (HNF) 1A cause HNF1A–maturity-onset diabetes of the young (HNF1A-MODY), the most common monogenic form of diabetes. To examine HNF1A-MODY-induced defects in gene expression, we performed a microarray analysis of the transcriptome of rat INS-1 cells inducibly expressing the common hot spot HNF1A frameshift mutation, Pro291fsinsC-HNF1A. Real-time quantitative PCR (qPCR), Western blotting, immunohistochemistry, reporter assays, and chromatin immunoprecipitation (ChIP) were used to validate alterations in gene expression and to explore biological activities of target genes. Twenty-four hours after induction of the mutant HNF1A protein, we identified a prominent down-regulation of the bone morphogenetic protein 3 gene (Bmp-3) mRNA expression. Reporter assays, qPCR, and Western blot analysis validated these results. In contrast, inducible expression of wild-type HNF1A led to a time-dependent increase in Bmp-3 mRNA and protein levels. Moreover, reduced protein levels of BMP-3 and insulin were detected in islets of transgenic HNF1A-MODY mice. Interestingly, treatment of naïve INS-1 cells or murine organotypic islet cultures with recombinant human BMP-3 potently increased their insulin levels and restored the decrease in SMAD2 phosphorylation and insulin gene expression induced by the HNF1A frameshift mutation. Our study suggests a critical link between HNF1A-MODY-induced alterations in Bmp-3 expression and insulin gene levels in INS-1 cells and indicates that the reduced expression of growth factors involved in tissue differentiation may play an important role in the pathophysiology of HNF1A-MODY. PMID:21628466

  11. Neutrophilic progression in a case of polycytemia vera mimicking chronic neutrophilic leukemia: clinical and molecular characterization.

    PubMed

    Castelli, Roberto; Cugno, Massimo; Gianelli, Umberto; Pancrazzi, Alessandro; Vannucchi, Alessandro Maria

    2015-04-01

    In a small subset of polycytemia vera (PV), neutrophilia not secondary to reactive conditions or treatment can develop and persist. Clinical significance and morphogenetic alterations associated with this uncommon phenomenon are not well defined. An 81-year-old Caucasian woman, affected by polycytemia vera lasting 17 years, presented in March 2012 with hyperleukocytosis, absolute neutrophilia, and thrombocytosis despite hydroxyurea treatment. All other laboratory parameters were normal, except for an increased neutrophil alkaline phosphatase and lactate dehydrogenase. Reactive neutrophilia due to infection or neoplasia have been ruled out by a total body computerized tomography scan, and by low levels of C reactive protein. Re-evaluation of bone marrow showed hypercellular smears with expansion of granulopoiesis while immature granulocytes were <10% and myeloblasts were <1%. Bone marrow trephine biopsy showed hypercellular marrow, with panmyelosis, increased myeloid/erithroid ratio, polymorphic clusters of megakaryocytes. A loose network of reticulin fibers with many intersections was identified by means of Gomori's silver impregnation. There were no hybrid BCR/ABL gene transcripts of p210, p190 and p230, no mutations in platelet derived growth factor receptors alpha and beta. Flow cytometry on the aspirate showed that CD34+ CD117+ myeloblasts constituted less than 1% of total marrow nucleated cells, mature granulocytes demonstrated persistent expression of CD33. Mutational analysis of the gene CSF3R by PCR amplification revealed no alterations in exons 14-17, including codons 615 and 618. The case presented here represents a possible evolution of PV, albeit very rare. The condition described here differs from the CNL for the persistence of morphological pictures typical of myeloproliferative diseases, for absence of CSF3R gene mutations and for the hyper expansion of the mature granulopoietic series. The clinical significance and morphogenetic alterations associated with this uncommon phenomenon are not well defined. Copyright © 2014 Elsevier GmbH. All rights reserved.

  12. Bone morphogenetic protein 4 induces differentiation of colorectal cancer stem cells and increases their response to chemotherapy in mice.

    PubMed

    Lombardo, Ylenia; Scopelliti, Alessandro; Cammareri, Patrizia; Todaro, Matilde; Iovino, Flora; Ricci-Vitiani, Lucia; Gulotta, Gaspare; Dieli, Francesco; de Maria, Ruggero; Stassi, Giorgio

    2011-01-01

    The limited clinical response observed in many patients with colorectal cancer may be related to the presence of chemoresistant colorectal cancer stem cells (CRC-SCs). Bone morphogenetic protein 4 (BMP4) promotes the differentiation of normal colonic stem cells. We investigated whether BMP4 might be used to induce differentiation of CRC-SCs and for therapeutic purposes. CRC-SCs were isolated from 25 tumor samples based on expression of CD133 or using a selection culture medium. BMP4 expression and activity on CRC-SCs were evaluated in vitro; progeny of the stem cells were evaluated by immunofluorescence, immunoblot, and flow cytometry analyses. The potential therapeutic effect of BMP4 was assessed in immunocompromised mice after injection of CRC-SCs that responded to chemotherapy (n = 4) or that did not (n = 2). CRC-SCs did not express BMP4 whereas differentiated cells did. Recombinant BMP4 promoted differentiation and apoptosis of CRC-SCs in 12 of 15 independent experiments; this effect did not depend on Small Mothers against decapentaplegic (Smad)4 expression level or microsatellite stability. BMP4 activated the canonical and noncanonical BMP signaling pathways, including phosphoInositide 3-kinase (PI3K) and PKB (protein kinase B)/AKT. Mutations in PI3K or loss of Phosphatase and Tensin homolog (PTEN) in Smad4-defective tumors made CRC-SCs unresponsive to BMP4. Administration of BMP4 to immunocompromised mice with tumors that arose from CRC-SCs increased the antitumor effects of 5-fluorouracil and oxaliplatin. BMP4 promotes terminal differentiation, apoptosis, and chemosensitization of CRC-SCs in tumors that do not have simultaneous mutations in Smad4 and constitutive activation of PI3K. BMP4 might be developed as a therapeutic agent against cancer stem cells in advanced colorectal tumors. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  13. MicroRNA-140 Suppresses Human Chondrocytes Hypertrophy by Targeting SMAD1 and Controlling the Bone Morphogenetic Protein Pathway in Osteoarthritis.

    PubMed

    Li, Canfeng; Hu, Qinshen; Chen, Zhuo; Shen, Bin; Yang, Jing; Kang, Pengde; Zhou, Zongke; Pei, Fuxing

    2018-05-01

    This study aimed to investigate the expression levels and relationship of bone morphogenetic proteins (BMPs) signaling molecules and microRNA-140 (miR-140) in human osteoarthritis (OA) chondrocytes. Different stage chondrocytes (normal cartilage, mid-stage OA and advanced-stage OA) were isolated from cartilage samples according to Kellgren and Lawrence criteria. The effect of miR-140 on BMPs signaling was evaluated by transfecting miR-140 mimic or inhibitor into chondrocytes. The expression of responsive genes was measured using real-time polymerase chain reaction and Western blotting analysis. There was a significant reduction in miR-140 and SOX9 expression in OA groups compared to the normal group, and there was a further reduction in the severe OA group compared to the moderate OA group. Compared with the normal group, the expression of ALK1, SMAD1, COL10A1 and MMP3 was higher in the OA groups, whereas the expression of COL2A1 was lower in the OA groups. In the moderate OA group, transfection with miR-140 mimic increased SMAD1, SOX9 and COL2A1 expression, but decreased COL10A1 expression. However, there was an opposite effect after transfecting miR-140 inhibitor with decreased SMAD1, SOX9 and COL2A1 expression, and increased COL10A1 expression. Interestingly, the biological effect of transfecting miR-140 mimic or inhibitor was similar in the severe OA group. SMAD1 and COL2A1 protein production followed the same pattern as their expression profile. miR-140 suppresses chondrocytes hypertrophy by controlling the BMPs signaling pathway, which highlights the importance of miR-140 in the maintenance of chondrocyte homeostasis and opens up novel avenues in OA therapeutic strategies. Copyright © 2018 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  14. Comparison of two independent systematic reviews of trials of recombinant human bone morphogenetic protein-2 (rhBMP-2): the Yale Open Data Access Medtronic Project.

    PubMed

    Low, Jeffrey; Ross, Joseph S; Ritchie, Jessica D; Gross, Cary P; Lehman, Richard; Lin, Haiqun; Fu, Rongwei; Stewart, Lesley A; Krumholz, Harlan M

    2017-02-15

    It is uncertain whether the replication of systematic reviews, particularly those with the same objectives and resources, would employ similar methods and/or arrive at identical findings. We compared the results and conclusions of two concurrent systematic reviews undertaken by two independent research teams provided with the same objectives, resources, and individual participant-level data. Two centers in the USA and UK were each provided with participant-level data on 17 multi-site clinical trials of recombinant human bone morphogenetic protein-2 (rhBMP-2). The teams were blinded to each other's methods and findings until after publication. We conducted a retrospective structured comparison of the results of the two systematic reviews. The main outcome measures included (1) trial inclusion criteria; (2) statistical methods; (3) summary efficacy and risk estimates; and (4) conclusions. The two research teams' meta-analyses inclusion criteria were broadly similar but differed slightly in trial inclusion and research methodology. They obtained similar results in summary estimates of most clinical outcomes and adverse events. Center A incorporated all trials into summary estimates of efficacy and harms, while Center B concentrated on analyses stratified by surgical approach. Center A found a statistically significant, but small, benefit whereas Center B reported no advantage. In the analysis of harms, neither showed an increased cancer risk at 48 months, although Center B reported a significant increase at 24 months. Conclusions reflected these differences in summary estimates of benefit balanced with small but potentially important risk of harm. Two independent groups given the same research objectives, data, resources, funding, and time produced broad general agreement but differed in several areas. These differences, the importance of which is debatable, indicate the value of the availability of data to allow for more than a single approach and a single interpretation of the data. PROSPERO CRD42012002040 and CRD42012001907 .

  15. Combination of BMP-2-releasing gelatin/β-TCP sponges with autologous bone marrow for bone regeneration of X-ray-irradiated rabbit ulnar defects.

    PubMed

    Yamamoto, Masaya; Hokugo, Akishige; Takahashi, Yoshitake; Nakano, Takayoshi; Hiraoka, Masahiro; Tabata, Yasuhiko

    2015-07-01

    The objective of this study is to evaluate the feasibility of gelatin sponges incorporating β-tricalcium phosphate (β-TCP) granules (gelatin/β-TCP sponges) to enhance bone regeneration at a segmental ulnar defect of rabbits with X-ray irradiation. After X-ray irradiation of the ulnar bone, segmental critical-sized defects of 20-mm length were created, and bone morphogenetic protein-2 (BMP-2)-releasing gelatin/β-TCP sponges with or without autologous bone marrow were applied to the defects to evaluate bone regeneration. Both gelatin/β-TCP sponges containing autologous bone marrow and BMP-2-releasing sponges enhanced bone regeneration at the ulna defect to a significantly greater extent than the empty sponges (control). However, in the X-ray-irradiated bone, the bone regeneration either by autologous bone marrow or BMP-2 was inhibited. When combined with autologous bone marrow, the BMP-2 exhibited significantly high osteoinductivity, irrespective of the X-ray irradiation. The bone mineral content at the ulna defect was similar to that of the intact bone. It is concluded that the combination of bone marrow with the BMP-2-releasing gelatin/β-TCP sponge is a promising technique to induce bone regeneration at segmental bone defects after X-ray irradiation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Bone morphogenetic protein 9 (BMP9) and BMP10 enhance tumor necrosis factor-α-induced monocyte recruitment to the vascular endothelium mainly via activin receptor-like kinase 2.

    PubMed

    Mitrofan, Claudia-Gabriela; Appleby, Sarah L; Nash, Gerard B; Mallat, Ziad; Chilvers, Edwin R; Upton, Paul D; Morrell, Nicholas W

    2017-08-18

    Bone morphogenetic proteins 9 and 10 (BMP9/BMP10) are circulating cytokines with important roles in endothelial homeostasis. The aim of this study was to investigate the roles of BMP9 and BMP10 in mediating monocyte-endothelial interactions using an in vitro flow adhesion assay. Herein, we report that whereas BMP9/BMP10 alone had no effect on monocyte recruitment, at higher concentrations both cytokines synergized with tumor necrosis factor-α (TNFα) to increase recruitment to the vascular endothelium. The BMP9/BMP10-mediated increase in monocyte recruitment in the presence of TNFα was associated with up-regulated expression levels of E-selectin, vascular cell adhesion molecule (VCAM-1), and intercellular adhesion molecule 1 (ICAM-1) on endothelial cells. Using siRNAs to type I and II BMP receptors and the signaling intermediaries (Smads), we demonstrated a key role for ALK2 in the BMP9/BMP10-induced surface expression of E-selectin, and both ALK1 and ALK2 in the up-regulation of VCAM-1 and ICAM-1. The type II receptors, BMPR-II and ACTR-IIA were both required for this response, as was Smad1/5. The up-regulation of cell surface adhesion molecules by BMP9/10 in the presence of TNFα was inhibited by LDN193189, which inhibits ALK2 but not ALK1. Furthermore, LDN193189 inhibited monocyte recruitment induced by TNFα and BMP9/10. BMP9/10 increased basal IκBα protein expression, but did not alter p65/RelA levels. Our findings suggest that higher concentrations of BMP9/BMP10 synergize with TNFα to induce the up-regulation of endothelial selectins and adhesion molecules, ultimately resulting in increased monocyte recruitment to the vascular endothelium. This process is mediated mainly via the ALK2 type I receptor, BMPR-II/ACTR-IIA type II receptors, and downstream Smad1/5 signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Engineering a morphogenetically active hydrogel for bioprinting of bioartificial tissue derived from human osteoblast-like SaOS-2 cells.

    PubMed

    Neufurth, Meik; Wang, Xiaohong; Schröder, Heinz C; Feng, Qingling; Diehl-Seifert, Bärbel; Ziebart, Thomas; Steffen, Renate; Wang, Shunfeng; Müller, Werner E G

    2014-10-01

    Sodium alginate hydrogel, stabilized with gelatin, is a suitable, biologically inert matrix that can be used for encapsulating and 3D bioprinting of bone-related SaOS-2 cells. However, the cells, embedded in this matrix, remain in a non-proliferating state. Here we show that addition of an overlay onto the bioprinted alginate/gelatine/SaOS-2 cell scaffold, consisting of agarose and the calcium salt of polyphosphate [polyP·Ca(2+)-complex], resulted in a marked increase in cell proliferation. In the presence of 100 μm polyP·Ca(2+)-complex, the cells proliferate with a generation time of approximately 47-55 h. In addition, the hardness of the alginate/gelatin hydrogel substantially increases in the presence of the polymer. The reduced Young's modulus for the alginate/gelatin hydrogel is approximately 13-14 kPa, and this value drops to approximately 0.5 kPa after incubation of the cell containing scaffolds for 5 d. In the presence of 100 μm polyP·Ca(2+)-complex, the reduced Young's modulus increases to about 22 kPa. The hardness of the polyP·Ca(2+)-complex containing hydrogel remains essentially constant if cells are absent in the matrix, but it drops to 3.2 kPa after a 5 d incubation period in the presence of SaOS-2 cells, indicating that polyP·Ca(2+)-complex becomes metabolized, degraded, by the cells. The alginate/gelatine-agarose system with polyP·Ca(2+)-complex cause a significant increase in the mineralization of the cells. SEM analyses revealed that the morphology of the mineral nodules formed on the surface of the cells embedded in the alginate/gelatin hydrogel do not significantly differ from the nodules on cells growing in monolayer cultures. The newly developed technique, using cells encapsulated into an alginate/gelatin hydrogel and a secondary layer containing the morphogenetically active, growth promoting polymer polyP·Ca(2+)-complex opens new possibilities for the application of 3D bioprinting in bone tissue engineering. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Bone Marrow Regeneration Promoted by Biophysically Sorted Osteoprogenitors From Mesenchymal Stromal Cells

    PubMed Central

    Poon, Zhiyong; Lee, Wong Cheng; Guan, Guofeng; Nyan, Lin Myint; Lim, Chwee Teck; Han, Jongyoon

    2015-01-01

    Human tissue repair deficiencies can be supplemented through strategies to isolate, expand in vitro, and reimplant regenerative cells that supplant damaged cells or stimulate endogenous repair mechanisms. Bone marrow-derived mesenchymal stromal cells (MSCs), a subset of which is described as mesenchymal stem cells, are leading candidates for cell-mediated bone repair and wound healing, with hundreds of ongoing clinical trials worldwide. An outstanding key challenge for successful clinical translation of MSCs is the capacity to produce large quantities of cells in vitro with uniform and relevant therapeutic properties. By leveraging biophysical traits of MSC subpopulations and label-free microfluidic cell sorting, we hypothesized and experimentally verified that MSCs of large diameter within expanded MSC cultures were osteoprogenitors that exhibited significantly greater efficacy over other MSC subpopulations in bone marrow repair. Systemic administration of osteoprogenitor MSCs significantly improved survival rates (>80%) as compared with other MSC subpopulations (0%) for preclinical murine bone marrow injury models. Osteoprogenitor MSCs also exerted potent therapeutic effects as “cell factories” that secreted high levels of regenerative factors such as interleukin-6 (IL-6), interleukin-8 (IL-8), vascular endothelial growth factor A, bone morphogenetic protein 2, epidermal growth factor, fibroblast growth factor 1, and angiopoietin-1; this resulted in increased cell proliferation, vessel formation, and reduced apoptosis in bone marrow. This MSC subpopulation mediated rescue of damaged marrow tissue via restoration of the hematopoiesis-supporting stroma, as well as subsequent hematopoiesis. Together, the capabilities described herein for label-freeisolation of regenerative osteoprogenitor MSCs can markedly improve the efficacy of MSC-based therapies. PMID:25411477

  19. Characteristics of contact and distance osteogenesis around modified implant surfaces in rabbit tibiae

    PubMed Central

    2017-01-01

    Purpose Contact and distance osteogenesis occur around all endosseous dental implants. However, the mechanisms underlying these processes have not been fully elucidated. We hypothesized that these processes occur independently of each other. To test this, we used titanium (Ti) tubes to physically separate contact and distance osteogenesis, thus allowing contact osteogenesis to be measured in the absence of possible triggers from distance osteogenesis. Methods Sandblasted and acid-etched (SLA) and modified SLA (modSLA) implants were used. Both types had been sandblasted with large grit and then etched with acid. The modSLA implants then underwent additional treatment to increase hydrophilicity. The implants were implanted into rabbit tibiae, and half were implanted within Ti tubes. The bone-to-implant contact (BIC) ratio was calculated for each implant. Immunohistochemical analyses of bone morphogenetic protein (BMP)-2 expression and new bone formation (Masson trichrome stain) were performed. Results The implants outside of Ti tubes were associated with good bone formation along the implant surface. Implantation within a Ti tube significantly reduced the BIC ratio (P<0.001). Compared with the modSLA implants, the SLA implants were associated with significantly higher BIC ratios, regardless of the presence or absence of Ti tubes (P=0.043). In the absence of Ti tubes, the bone adjacent to the implant had areas of new bone formation that expressed BMP-2 at high levels. Conclusions This study disproved the null hypothesis and suggested that contact osteogenesis is initiated by signals from the old bone that undergoes distance osteogenesis after drilling. This signal may be BMP-2. PMID:28680714

  20. Bioactive quinone derivatives from the marine brown alga Sargassum thunbergii induce anti-adipogenic and pro-osteoblastogenic activities.

    PubMed

    Kim, Jung-Ae; Karadeniz, Fatih; Ahn, Byul-Nim; Kwon, Myeong Sook; Mun, Ok-Ju; Bae, Min Joo; Seo, Youngwan; Kim, Mihyang; Lee, Sang-Hyeon; Kim, Yuck Yong; Mi-Soon, Jang; Kong, Chang-Suk

    2016-02-01

    Health problems related to the lack of bone formation are a major problem for ageing populations in the modern world. As a part of the ongoing trend to develop natural substances that attenuate bone loss in osteoporosis, the effects of the edible brown alga Sargassum thunbergii and its active contents on adipogenic differentiation in 3T3-L1 fibroblasts and osteoblast differentiation in MC3T3-E1 pre-osteoblasts were evaluated. Treatment with S. thunbergii significantly reduced lipid accumulation and expression of adipogenic differentiation markers such as peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α and sterol regulatory element binding protein 1c. In addition, S. thunbergii successfully enhanced osteoblast differentiation as indicated by increased alkaline phosphatase activity along raised levels of osteoblastogenesis indicators, namely bone morphogenetic protein-2, osteocalcin and collagen type I. Two compounds, sargaquinoic and sargahydroquinoic acid, were isolated from active extract and shown to be active by means of osteogenesis inducement. S. thunbergii could be a source for functional food ingredients for improved treatment of osteoporosis and obesity. © 2015 Society of Chemical Industry.

  1. Effects of different growth factors and carriers on bone regeneration: a systematic review.

    PubMed

    Khojasteh, Arash; Behnia, Hossein; Naghdi, Navid; Esmaeelinejad, Mohammad; Alikhassy, Zahra; Stevens, Mark

    2013-12-01

    The application and subsequent investigations in the use of varied osteogenic growth factors in bone regeneration procedures have grown dramatically over the past several years. Owing to this rapid gain in popularity and documentation, a review was undertaken to evaluate the in vivo effects of growth factors on bone regeneration. Using related key words, electronic databases (Medline, Embase, and Cochrane) were searched for articles published from 1999 to April 2010 to find growth factor application in bone regeneration in human or animal models. A total of 63 articles were matched with the inclusion criteria of this study. Bone morphogenetic protein 2 (BMP-2) was the most studied growth factor. Carriers for the delivery, experimental sites, and methods of evaluation were different, and therefore articles did not come to a general agreement. Within the limitations of this review, BMP-2 may be an appropriate growth factor for osteogenesis. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. The Wnt signaling pathway is differentially expressed during the bovine herpesvirus 1 latency-reactivation cycle: evidence that two protein kinases associated with neuronal survival (Akt3 and bone morphogenetic protein....

    USDA-ARS?s Scientific Manuscript database

    Sensory neurons in trigeminal ganglia (TG) of calves latently infected with bovine herpesvirus 1 (BoHV-1) abundantly express latency-related (LR) gene products, including a protein (ORF2) and two micro-RNAs. Recent studies in mouse neuroblastoma cells (Neuro-2A) demonstrated ORF2 interacts with ß-ca...

  3. Bone morphogenetic protein 2 (BMP2) and krüppel-like factor 9 (KLF9) cross-regulation in uterine stromal cells promotes timing of uterine endometrial receptivity

    USDA-ARS?s Scientific Manuscript database

    An out-of-phase uterus is considered to be a major cause of infertility in mammals. Delayed on-time implantation of developing blastocysts, due to asynchronous endometrial development, results in reduced litter size in mice. The dysregulation of events in the transition from a pre-receptive to a re...

  4. Deficiency of Retinaldehyde Dehydrogenase 1 Induces BMP2 and Increases Bone Mass In Vivo

    PubMed Central

    Nallamshetty, Shriram; Wang, Hong; Rhee, Eun-Jung; Kiefer, Florian W.; Brown, Jonathan D.; Lotinun, Sutada; Le, Phuong; Baron, Roland; Rosen, Clifford J.; Plutzky, Jorge

    2013-01-01

    The effects of retinoids, the structural derivatives of vitamin A (retinol), on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA) and its precursor all trans retinaldehyde (Rald), exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1), the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT) demonstrated that Aldh1a1-deficient (Aldh1a1−/−) female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT) mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1−/− mice. In serum assays, Aldh1a1−/− mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1−/− mesenchymal stem cells (MSCs) expressed significantly higher levels of bone morphogenetic protein 2 (BMP2) and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1−/− mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1−/− mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR)-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling. PMID:23951127

  5. Genetic analyses of bone morphogenetic protein 2, 4 and 7 in congenital combined pituitary hormone deficiency.

    PubMed

    Breitfeld, Jana; Martens, Susanne; Klammt, Jürgen; Schlicke, Marina; Pfäffle, Roland; Krause, Kerstin; Weidle, Kerstin; Schleinitz, Dorit; Stumvoll, Michael; Führer, Dagmar; Kovacs, Peter; Tönjes, Anke

    2013-12-01

    The complex process of development of the pituitary gland is regulated by a number of signalling molecules and transcription factors. Mutations in these factors have been identified in rare cases of congenital hypopituitarism but for most subjects with combined pituitary hormone deficiency (CPHD) genetic causes are unknown. Bone morphogenetic proteins (BMPs) affect induction and growth of the pituitary primordium and thus represent plausible candidates for mutational screening of patients with CPHD. We sequenced BMP2, 4 and 7 in 19 subjects with CPHD. For validation purposes, novel genetic variants were genotyped in 1046 healthy subjects. Additionally, potential functional relevance for most promising variants has been assessed by phylogenetic analyses and prediction of effects on protein structure. Sequencing revealed two novel variants and confirmed 30 previously known polymorphisms and mutations in BMP2, 4 and 7. Although phylogenetic analyses indicated that these variants map within strongly conserved gene regions, there was no direct support for their impact on protein structure when applying predictive bioinformatics tools. A mutation in the BMP4 coding region resulting in an amino acid exchange (p.Arg300Pro) appeared most interesting among the identified variants. Further functional analyses are required to ultimately map the relevance of these novel variants in CPHD.

  6. Role of RGM coreceptors in bone morphogenetic protein signaling

    PubMed Central

    Halbrooks, Peter J; Ding, Ru; Wozney, John M; Bain, Gerard

    2007-01-01

    Background The repulsive guidance molecule (RGM) proteins, originally discovered for their roles in neuronal development, have been recently identified as co-receptors in the bone morphogenetic protein (BMP) signaling pathway. BMPs are members of the TGFβ superfamily of signaling cytokines, and serve to regulate many aspects of cellular growth and differentiation. Results Here, we investigate whether RGMa, RGMb, and RGMc play required roles in BMP and TGFβ signaling in the mouse myoblast C2C12 cell line. These cells are responsive to BMPs and are frequently used to study BMP/TGFβ signaling pathways. Using siRNA reagents to specifically knock down each RGM protein, we show that the RGM co-receptors are required for significant BMP signaling as reported by two cell-based BMP activity assays: endogenous alkaline phosphatase activity and a luciferase-based BMP reporter assay. Similar cell-based assays using a TGFβ-induced luciferase reporter show that the RGM co-receptors are not required for TGFβ signaling. The binding interaction of each RGM co-receptor to each of BMP2 and BMP12 is observed and quantified, and equilibrium dissociation constants in the low nanomolar range are reported. Conclusion Our results demonstrate that the RGMs play a significant role in BMP signaling and reveal that these molecules cannot functionally compensate for one another. PMID:17615080

  7. Genetic analyses of bone morphogenetic protein 2, 4 and 7 in congenital combined pituitary hormone deficiency

    PubMed Central

    2013-01-01

    Background The complex process of development of the pituitary gland is regulated by a number of signalling molecules and transcription factors. Mutations in these factors have been identified in rare cases of congenital hypopituitarism but for most subjects with combined pituitary hormone deficiency (CPHD) genetic causes are unknown. Bone morphogenetic proteins (BMPs) affect induction and growth of the pituitary primordium and thus represent plausible candidates for mutational screening of patients with CPHD. Methods We sequenced BMP2, 4 and 7 in 19 subjects with CPHD. For validation purposes, novel genetic variants were genotyped in 1046 healthy subjects. Additionally, potential functional relevance for most promising variants has been assessed by phylogenetic analyses and prediction of effects on protein structure. Results Sequencing revealed two novel variants and confirmed 30 previously known polymorphisms and mutations in BMP2, 4 and 7. Although phylogenetic analyses indicated that these variants map within strongly conserved gene regions, there was no direct support for their impact on protein structure when applying predictive bioinformatics tools. Conclusions A mutation in the BMP4 coding region resulting in an amino acid exchange (p.Arg300Pro) appeared most interesting among the identified variants. Further functional analyses are required to ultimately map the relevance of these novel variants in CPHD. PMID:24289245

  8. Follistatin-like 1 (Fstl1) is a bone morphogenetic protein (BMP) 4 signaling antagonist in controlling mouse lung development

    PubMed Central

    Geng, Yan; Dong, Yingying; Yu, Mingyan; Zhang, Long; Yan, Xiaohua; Sun, Jingxia; Qiao, Long; Geng, Huixia; Nakajima, Masahiro; Furuichi, Tatsuya; Ikegawa, Shiro; Gao, Xiang; Chen, Ye-Guang; Jiang, Dianhua; Ning, Wen

    2011-01-01

    Lung morphogenesis is a well orchestrated, tightly regulated process through several molecular pathways, including TGF-β/bone morphogenetic protein (BMP) signaling. Alteration of these signaling pathways leads to lung malformation. We investigated the role of Follistatin-like 1 (Fstl1), a secreted follistatin-module–containing glycoprotein, in lung development. Deletion of Fstl1 in mice led to postnatal lethality as a result of respiratory failure. Analysis of the mutant phenotype showed that Fstl1 is essential for tracheal cartilage formation and alveolar maturation. Deletion of the Fstl1 gene resulted in malformed tracheal rings manifested as discontinued rings and reduced ring number. Fstl1-deficient mice displayed septal hypercellularity and end-expiratory atelectasis, which were associated with impaired differentiation of distal alveolar epithelial cells and insufficient production of mature surfactant proteins. Mechanistically, Fstl1 interacted directly with BMP4, negatively regulated BMP4/Smad1/5/8 signaling, and inhibited BMP4-induced surfactant gene expression. Reducing BMP signaling activity by Noggin rescued pulmonary atelectasis of Fstl1-deficient mice. Therefore, we provide in vivo and in vitro evidence to demonstrate that Fstl1 modulates lung development and alveolar maturation, in part, through BMP4 signaling. PMID:21482757

  9. A tissue engineering solution for segmental defect regeneration in load-bearing long bones.

    PubMed

    Reichert, Johannes C; Cipitria, Amaia; Epari, Devakara R; Saifzadeh, Siamak; Krishnakanth, Pushpanjali; Berner, Arne; Woodruff, Maria A; Schell, Hanna; Mehta, Manav; Schuetz, Michael A; Duda, Georg N; Hutmacher, Dietmar W

    2012-07-04

    The reconstruction of large defects (>10 mm) in humans usually relies on bone graft transplantation. Limiting factors include availability of graft material, comorbidity, and insufficient integration into the damaged bone. We compare the gold standard autograft with biodegradable composite scaffolds consisting of medical-grade polycaprolactone and tricalcium phosphate combined with autologous bone marrow-derived mesenchymal stem cells (MSCs) or recombinant human bone morphogenetic protein 7 (rhBMP-7). Critical-sized defects in sheep--a model closely resembling human bone formation and structure--were treated with autograft, rhBMP-7, or MSCs. Bridging was observed within 3 months for both the autograft and the rhBMP-7 treatment. After 12 months, biomechanical analysis and microcomputed tomography imaging showed significantly greater bone formation and superior strength for the biomaterial scaffolds loaded with rhBMP-7 compared to the autograft. Axial bone distribution was greater at the interfaces. With rhBMP-7, at 3 months, the radial bone distribution within the scaffolds was homogeneous. At 12 months, however, significantly more bone was found in the scaffold architecture, indicating bone remodeling. Scaffolds alone or with MSC inclusion did not induce levels of bone formation comparable to those of the autograft and rhBMP-7 groups. Applied clinically, this approach using rhBMP-7 could overcome autograft-associated limitations.

  10. [Effects of cuttlefish bone-bone morphogenetic protein composite material on osteogenesis and revascularization of bone defect in rats].

    PubMed

    Liu, Yuan; Yu, Jiang; Bai, Jie; Gu, Jin-song; Cai, Bin; Zhou, Xia

    2013-12-01

    To study the effects of cuttlefish bone-bone morphogenetic protein (BMP) composite material on osteogenesis and revascularization of bone defect in rats. The cuttlefish bone was formed into cylinder with the diameter of about 5 mm and height of about 2 mm after the shell was removed, and then it was soaked in the recombinant human BMP 2 to make a cuttlefish bone-BMP (CBB) composite material. Thirty SD rats, with a defect of skull in every rat, were divided into the CBB and pure cuttlefish bone (PCB) groups according to the random number table, with 15 rats in each group. The rats in the group CBB and group PCB were transplanted with the corresponding material to repair the skull defect. At post transplantation week (PTW) 4, 6, and 8, 5 rats from every group were sacrificed by exsanguination, and ink perfusion was performed. One day later, all the transplants and part of the skull surrounding the defect were harvested, and general observation was conducted at the same time. The specimens were paraffin sectioned for HE staining and Masson staining. The area of microvessel and the area of newborn bone were observed and analyzed through histopathological techniques and image collection system. Data were processed with the analysis of variance of factorial design and LSD test. The correlation between the area of microvessel and the area of newborn bone of the group CBB was analyzed with Pearson correlation analysis. (1) The general observation of the transplant region showed that the transplants were encapsulated by a capsule of fibrous connective tissue. The texture of capsule was soft and relatively thick at PTW 4. The texture was tenacious and thin, but rather compact at PTW 6 and 8. The transplants became gelatinous at PTW 4, and similar to the cartilage tissue at PTW 6 and 8. (2) Histological observation showed that the structure of the transplants in two groups was damaged at PTW 4. A moderate quantity of inflammatory cell infiltration could be observed. The amounts of the primary bone trabeculae and microvessels in group CBB were more abundant than those of group PCB, while the number of osteoclasts was less than those of group PCB. At PTW 6, the inflammatory cell infiltration in the transplants in both groups decreased obviously, the cuttlefish bone was found to be further degraded, and the number of newborn microvessels was increased. There were mature bone trabeculae around the transplants in both groups. And there were also mature bone trabeculae in the degraded CBB in group CBB. At PTW 8, the inflammatory reaction in the transplants in both groups disappeared; there were more mature bone trabeculae; the structure of the cuttlefish bone was found to be damaged basically. Bone trabeculae in group PCB were found around the transplant, while the bone trabeculae could be observed not only around the transplant but also in the degraded CBB in group CBB. The amount of the microvessels in group CBB was still larger than that of group PCB. (3) From PTW 4 to 8, the area of microvessel in group CBB [(63 ± 4), ( 136 ± 36), ( 347 ± 31) µm(2)] was larger than that in group PCB [(44 ± 7), (73 ± 4), (268 ± 42) µm(2), P < 0.05 or P < 0.01]. From PTW 4 to 8, the area of newborn bone in group CBB [(236 ± 26), (339 ± 42), (553 ± 40) µm(2)] was larger than that in group PCB [(137 ± 15), (243 ± 21), (445 ± 29) µm(2), with P values all below 0.01]. (4) The relation between the area of microvessel and the area of newborn bone was significantly positive (r = 0.948, P = 0.001). The CBB may exert good effect on osteogenesis and vascularization of rats with bone defect. It is a good three dimensional scaffold in bone tissue engineering.

  11. Recombinant human bone morphogenetic protein-2 stimulates bone formation during interfrontal suture expansion in rabbits.

    PubMed

    Liu, Sean Shih-Yao; Xu, Haisong; Sun, Jun; Kontogiorgos, Elias; Whittington, Patrick R; Misner, Kenner G; Kyung, Hee-Moon; Buschang, Peter H; Opperman, Lynne A

    2013-08-01

    Suture expansion stimulates bone growth to correct craniofacial deficiencies but has a high potential of treatment relapse. The objective of this study was to investigate whether there is a dose-dependent relationship between the recombinant human bone morphogenetic protein-2 (rhBMP-2) and bone formation during suture expansion. Fifty 6-week-old male New Zealand white rabbits were randomly assigned to 5 groups to receive 0 (control), 0.01, 0.025, 0.1, or 0.4 mg/mL of rhBMP-2 delivered by absorbable collagen sponge placed over the interfrontal suture. The suture was expanded for 33 days by 200 g of constant force via a spring anchored with 2 miniscrew implants. Distance of suture expansion, suture volume, and cross-sectional area after expansion were measured using radiographs with bone markers and microcomputed tomography. Suture widths and mineralization appositional rates were calculated based on the widths between bone labels under an epifluorescent microscope. Software (Multilevel Win 2.0; University of Bristol, Bristol, United Kingdom) was used to model distance of suture expansion over time as polynomials to compare group differences. Wilcoxon signed rank tests were performed to compare the suture volume and cross-sectional area, mineral apposition rate, and suture width between groups. The significance level was set at P = 0.05. Whereas the sutures were expanded in all groups, sutures were expanded by significantly greater amounts in the control and the 0.01 mg/mL groups without fusing the sutures than in the 0.025, 0.1, and 0.4 mg/mL groups with fusing sutures. Compared with the controls, the 0.01 mg/mL group showed significantly lower suture volumes, cross-sectional areas, and suture widths after expansion. The mineral apposition rate was significantly higher in the 0.01 mg/mL group than in the controls from days 10 to 30. The 0.01 mg/mL dose of rhBMP-2 delivered by absorbable collagen sponge can stimulate bone formation at the bony edges of the suture during suture expansion; however, higher concentrations cause suture fusion. With an appropriate concentration, rhBMP-2 might facilitate suture expansion for clinical uses. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  12. Is Bone Morphogenetic Protein-2 as Effective as Alveolar Distraction Osteogenesis for Vertical Bone Regeneration?

    PubMed

    Reuss, Jose M; Pi-Anfruns, Joan; Moy, Peter K

    2018-04-01

    The aim of this study was to assess the clinical effectiveness of alveolar distraction osteogenesis (ADO) versus recombinant human bone morphogenetic protein-2 (rh-BMP-2) for vertical ridge augmentation. Few data have been published on vertical bone regeneration using rh-BMP-2. The authors implemented a retrospective cohort study and enrolled a sample composed of patients with deficient alveolar vertical bone height. The primary predictor variable was vertical augmentation with BMP-2 and a titanium mesh or ADO. The primary outcome variable was gain in vertical bone height (millimeters) measured using computed tomography. The secondary outcome variable was postoperative complications, namely need for further grafting before or simultaneous with implant placement, soft tissue dehiscence, paresthesia, infection, implant failure, and pain. Other outcomes included implant stability at time of placement and follow-up (implant stability quotient by resonance frequency analysis), surgical time (minutes), and total treatment time until implant placement (weeks). Other study variables included location of reconstruction (maxilla or mandible). Appropriate bivariate statistics were computed and statistical significance was set a P value less than .05. The retrospective review yielded 21 patients in the BMP group and 19 in the ADO group. For the BMP-2 group, the average vertical bone gain was 2.96 ± 1.8 mm overall (maxilla, mean 3.6 ± 3.1 mm; mandible, mean 2.32 ± 1.8 mm). For the ADO group, this gain was 4 ± 1.69 mm overall (maxilla, mean 2.8 ± 1.94 mm; mandible, mean 5.2 ± 4.67 mm). For complications, group BMP showed a statistically minor tendency for more postoperative problems, such as wound dehiscence. For implant survival, group BMP showed a 92.2% survival rate versus 96.3% in group ADO at 3 to 45 months after delivery of the prosthesis (average, 22 months). The 2 techniques showed similar values in absolute vertical bone gain. Group ADO showed a slightly better outcome in outright vertical regenerative potential, albeit with a more frequent need for regrafting before and simultaneous with implant placement. Group BMP showed a lesser need for regrafting, despite having a higher postoperative complication rate. Copyright © 2017 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Recombinant human bone morphogenetic protein-2 versus autogenous iliac crest bone graft for lumbar fusion: a meta-analysis of ten randomized controlled trials.

    PubMed

    Chen, Zhiguang; Ba, Gen; Shen, Tao; Fu, Qin

    2012-12-01

    Recombinant human bone morphogenetic protein-2 (rhBMP-2) as a substitute for iliac crest bone graft (ICBG) has been increasingly widely used in lumbar fusion. It has been proven non-inferior in fusion success and clinical outcomes when compared with ICBG. However, increasingly, some potentially uncommon and serious complications associated with the use of rhBMP-2 have been of great concern to surgeons. The purpose of this study was to determine whether rhBMP-2 could be considered an effective and, more importantly, a relatively safe substitute for ICBG in lumbar fusion. Randomized controlled trials that compared rhBMP-2 with ICBG for lumbar fusion were identified by computer and manual searching. The risk of bias and clinical relevance of the included studies were assessed. Publication bias was explored using funnel plot and statistical tests (Egger's test and Begg's test). Meta-analyses were performed using the Cochrane systematic review methods. Ten randomized controlled trials (1,342 patients) met the inclusion criteria. Compared with ICBG, the use of rhBMP-2 significantly decreased the risk of fusion failure at all time intervals (6 months: p < 0.0001, RR = 0.55, 95 % CI = 0.42-0.72; 12 months: p = 0.0003, RR = 0.53, 95 % CI = 0.37-0.75; 24 months: p < 0.00001, RR = 0.31, 95 % CI = 0.21-0.46) and the rate of reoperation (p = 0.0001, RR = 0.52, 95 % CI = 0.37-0.72). There was no statistical difference in clinical improvement on the Oswestry Disability Index, although a favorable trend in the rhBMP-2 group was found (p = 0.12, RR = 0.73, 95 % CI = 0.49-1.08). Subgroup analyses stratified by the type of surgical procedure yielded similar results. Owing to the different data formats, meta-analysis on adverse events was not performed. RhBMP-2 was superior to the ICBG for achieving fusion success and avoiding reoperation. However, evidence from the Food and Drug Administration document and subsequent independent studies has demonstrated that original, industry-sponsored trials underestimated rhBMP-2-related adverse events. There are still security risks in the use of rhBMP-2.

  14. Bone morphogenetic protein 7 and autologous bone graft in revision surgery for non-union after lumbar interbody fusion.

    PubMed

    Werle, Stephan; AbuNahleh, Kais; Boehm, Heinrich

    2016-08-01

    Potential adverse and unknown long-term effects as well as additional costs limit the use of BMPs (Bone morphogenetic proteins) in primary fusion procedures. However, the proven osteoinductive properties render BMPs attractive for the attempt to reach fusion of symptomatic non-unions. The aim of this study is to evaluate the fusion rate and potential disadvantages of eptotermin alfa (rhBMP-7) used with autologous bone graft in revision procedures for lumbar pseudoarthrosis. At our institution, rhBMP-7 has been used to improve fusion rates in revision surgery for symptomatic pseudoarthrosis during the past 10 years. Eighty-four fusion procedures using rhBMP-7 between 08/2003 and 07/2011 were revisions due to symptomatic lumbar pseudoarthrosis. The surgical approach was posterior in three and combined anterior-posterior in 71 patients. Of those, 74 patients had either reached fusion or had follow-up of at least 39.5 months (range 21-80 months) in the case of pseudoarthrosis. These 74 patients have been included in a retrospective follow-up study. In 60 patients (81.1 %) the rhBMP-7 procedure was successful. In 14 patients, pseudoarthrosis persisted or fusion was questionable. Of those patients 12 accounted for persisting L5-S1 non-union. Persisting non-unions were found in 26.7 % of the study after four or more segment instrumentations compared to the 16.9 % after mono-, bi-, or three-segment instrumentation, and in four of 14 patients with spondylodesis of three or more levels above a pseudoarthrotic lumbosacral junction. Adverse effects related to the use of eptotermin alfa were rare in this group with symptomatic ectopic bone formation in one patient. Using rhBMP-7 with autologous bone graft in revisions for lumbar pseudoarthrosis via an anterior approach is safe and can lead to fusion even under unfavorable biomechanical conditions. However, successful outcome depends on the individual constellation. Treatment of non-unions of the lumbosacral junction remains especially difficult in cases with solid fusions above those pseudoarthrotic levels. 4; retrospective follow-up study.

  15. The efficacy of routine use of recombinant human bone morphogenetic protein-2 in occipitocervical and atlantoaxial fusions of the pediatric spine: a minimum of 12 months' follow-up with computed tomography.

    PubMed

    Sayama, Christina; Hadley, Caroline; Monaco, Gina N; Sen, Anish; Brayton, Alison; Briceño, Valentina; Tran, Brandon H; Ryan, Sheila L; Luerssen, Thomas G; Fulkerson, Daniel; Jea, Andrew

    2015-07-01

    OBJECT The purpose of this study focusing on fusion rate was to determine the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) use in posterior instrumented fusions of the craniocervical junction in the pediatric population. The authors previously reported the short-term (mean follow-up 11 months) safety and efficacy of rhBMP-2 use in the pediatric age group. The present study reports on their long-term results (minimum of 12 months' follow-up) and focuses on efficacy. METHODS The authors performed a retrospective review of 83 consecutive pediatric patients who had undergone posterior occipitocervical or atlantoaxial spine fusion at Texas Children's Hospital or Riley Children's Hospital during the period from October 2007 to October 2012. Forty-nine patients were excluded from further analysis because of death, loss to follow-up, or lack of CT evaluation of fusion at 12 or more months after surgery. Fusion was determined by postoperative CT scan at a minimum of 12 months after surgery. The fusion was graded and classified by a board-certified fellowship-trained pediatric neuroradiologist. Other factors, such as patient age, diagnosis, number of vertebral levels fused, use of allograft or autograft, dosage of bone morphogenetic protein (BMP), and use of postoperative orthosis, were recorded. RESULTS Thirty-four patients had a CT scan at least 12 months after surgery. The average age of the patients at surgery was 8 years, 1 month (range 10 months-17 years). The mean follow-up was 27.7 months (range 12-81 months). There were 37 fusion procedures in 34 patients. Solid fusion (CT Grade 4 or 4-) was achieved in 89.2% of attempts (33 of 37), while incomplete fusion or failure of fusion was seen in 10.8%. Based on logistic regression analysis, there was no significant association between solid fusion and age, sex, BMP dose, type of graft material, use of postoperative orthosis, or number of levels fused. Three of 34 patients (8.8%) required revision surgery. CONCLUSIONS Despite the large number of adult studies reporting positive effects of BMP on bone fusion, our long-term outcomes using rhBMP-2 in the pediatric population suggest that rates of fusion failure are higher than observed in contemporary adult and pediatric reports of occipitocervical and atlantoaxial spine fusions.

  16. Hepatocyte growth factor improves bone regeneration via the bone morphogenetic protein‑2‑mediated NF‑κB signaling pathway.

    PubMed

    Zhen, Ruixin; Yang, Jianing; Wang, Yu; Li, Yubo; Chen, Bin; Song, Youxin; Ma, Guiyun; Yang, Bo

    2018-04-01

    Bone regeneration is an important process associated with the treatment of osteonecrosis, which is caused by various factors. Hepatocyte growth factor (HGF) is an active biological factor that has multifunctional roles in cell biology, life sciences and clinical medicine. It has previously been suggested that bone morphogenetic protein (BMP)‑2 exerts beneficial roles in bone formation, repair and angiogenesis in the femoral head. The present study aimed to investigate the benefits and molecular mechanisms of HGF in bone regeneration. The viability of osteoblasts and osteoclasts were studied in vitro. In addition, the expression levels of tumor necrosis factor (TNF)‑α, monocyte chemotactic protein (MCP)‑1, interleukin (IL)‑1 and IL‑6 were detected in a mouse fracture model following treatment with HGF. The expression and activity of nuclear factor (NF)‑κB were also analyzed in osteocytes post‑treatment with HGF. Histological analysis was used to determine the therapeutic effects of HGF on mice with fractures. The migration and differentiation of osteoblasts and osteoclasts were investigated in HGF‑incubated cells. Furthermore, angiogenesis and BMP‑2 expression were analyzed in the mouse fracture model post‑treatment with HGF. The results indicated that HGF regulates the cell viability of osteoblasts and osteoclasts, and also balanced the ratio between osteoblasts and osteoclasts. In addition, HGF decreased the serum expression levels of TNF‑α, MCP‑1, IL‑1 and IL‑6 in experimental mice. The results of a mechanistic analysis demonstrated that HGF upregulated p65, IκB kinase‑β and IκBα expression in osteoblasts from experimental mice. In addition, the expression levels of vascular endothelial growth factor, BMP‑2 receptor, receptor activator of NF‑κB ligand and macrophage colony‑stimulating factor were upregulated by HGF, which may effectively promote blood vessel regeneration, and contribute to the formation and revascularization of tissue‑engineered bone. Furthermore, HGF promoted BMP‑2 expression and enhanced angiogenesis at the fracture location. These results suggested that HGF treatment may significantly promote bone regeneration in a mouse fracture model. In conclusion, these results indicated that HGF is involved in bone regeneration, angiogenesis and the balance between osteoblasts and osteoclasts, thus suggesting that HGF may be considered a potential agent for the treatment of fractures via the promotion of bone regeneration through regulation of the BMP‑2‑mediated NF‑κB signaling pathway.

  17. Bone Morphogenetic Protein-2 Adsorption onto Poly-ɛ-caprolactone Better Preserves Bioactivity In Vitro and Produces More Bone In Vivo than Conjugation Under Clinically Relevant Loading Scenarios

    PubMed Central

    Patel, Janki J.; Flanagan, Colleen L.

    2015-01-01

    Background: One strategy to reconstruct large bone defects is to prefabricate a vascularized flap by implanting a biomaterial scaffold with associated biologics into the latissimus dorsi and then transplanting this construct to the defect site after a maturation period. This strategy, similar to all clinically and regulatory feasible biologic approaches to surgical reconstruction, requires the ability to quickly (<1 h within an operating room) and efficiently bind biologics to scaffolds. It also requires the ability to localize biologic delivery. In this study, we investigated the efficacy of binding bone morphogenetic protein-2 (BMP2) to poly-ɛ-caprolactone (PCL) using adsorption and conjugation as a function of time. Methods: BMP2 was adsorbed (Ads) or conjugated (Conj) to PCL scaffolds with the same three-dimensional printed architecture while altering exposure time (0.5, 1, 5, and 16 h), temperature (4°C, 23°C), and BMP2 concentration (1.4, 5, 20, and 65 μg/mL). The in vitro release was quantified, and C2C12 cell alkaline phosphatase (ALP) expression was used to confirm bioactivity. Scaffolds with either 65 or 20 μg/mL Ads or Conj BMP2 for 1 h at 23°C were implanted subcutaneously in mice to evaluate in vivo bone regeneration. Micro-computed tomography, compression testing, and histology were performed to characterize bone regeneration. Results: After 1 h exposure to 65 μg/mL BMP2 at 23°C, Conj and Ads resulted in 12.83±1.78 and 10.78±1.49 μg BMP2 attached, respectively. Adsorption resulted in a positive ALP response and had a small burst release; whereas conjugation provided a sustained release with negligible ALP production, indicating that the conjugated BMP2 may not be bioavailable. Adsorbed 65 μg/mL BMP2 solution resulted in the greatest regenerated bone volume (15.0±3.0 mm3), elastic modulus (20.1±3.0 MPa), and %bone ingrowth in the scaffold interior (17.2%±5.4%) when compared with conjugation. Conclusion: Adsorption may be optimal for the clinical application of prefabricating bone flaps due to BMP2 binding in a short exposure time, retained BMP2 bioactivity, and bone growth adhering to scaffold geometry and into pores with healthy marrow development. PMID:25345571

  18. Bone Morphogenetic Protein-2 Adsorption onto Poly-ɛ-caprolactone Better Preserves Bioactivity In Vitro and Produces More Bone In Vivo than Conjugation Under Clinically Relevant Loading Scenarios.

    PubMed

    Patel, Janki J; Flanagan, Colleen L; Hollister, Scott J

    2015-05-01

    One strategy to reconstruct large bone defects is to prefabricate a vascularized flap by implanting a biomaterial scaffold with associated biologics into the latissimus dorsi and then transplanting this construct to the defect site after a maturation period. This strategy, similar to all clinically and regulatory feasible biologic approaches to surgical reconstruction, requires the ability to quickly (<1 h within an operating room) and efficiently bind biologics to scaffolds. It also requires the ability to localize biologic delivery. In this study, we investigated the efficacy of binding bone morphogenetic protein-2 (BMP2) to poly-ɛ-caprolactone (PCL) using adsorption and conjugation as a function of time. BMP2 was adsorbed (Ads) or conjugated (Conj) to PCL scaffolds with the same three-dimensional printed architecture while altering exposure time (0.5, 1, 5, and 16 h), temperature (4°C, 23°C), and BMP2 concentration (1.4, 5, 20, and 65 μg/mL). The in vitro release was quantified, and C2C12 cell alkaline phosphatase (ALP) expression was used to confirm bioactivity. Scaffolds with either 65 or 20 μg/mL Ads or Conj BMP2 for 1 h at 23°C were implanted subcutaneously in mice to evaluate in vivo bone regeneration. Micro-computed tomography, compression testing, and histology were performed to characterize bone regeneration. After 1 h exposure to 65 μg/mL BMP2 at 23°C, Conj and Ads resulted in 12.83 ± 1.78 and 10.78 ± 1.49 μg BMP2 attached, respectively. Adsorption resulted in a positive ALP response and had a small burst release; whereas conjugation provided a sustained release with negligible ALP production, indicating that the conjugated BMP2 may not be bioavailable. Adsorbed 65 μg/mL BMP2 solution resulted in the greatest regenerated bone volume (15.0 ± 3.0 mm³), elastic modulus (20.1 ± 3.0 MPa), and %bone ingrowth in the scaffold interior (17.2% ± 5.4%) when compared with conjugation. Adsorption may be optimal for the clinical application of prefabricating bone flaps due to BMP2 binding in a short exposure time, retained BMP2 bioactivity, and bone growth adhering to scaffold geometry and into pores with healthy marrow development.

  19. Recombinant human bone morphogenetic protein 2 outcomes for maxillary sinus floor augmentation: a systematic review and meta-analysis.

    PubMed

    Lin, Guo-Hao; Lim, Glendale; Chan, Hsun-Liang; Giannobile, William V; Wang, Hom-Lay

    2016-11-01

    To study the effect of the recombinant human bone morphogenetic protein 2 (rhBMP-2) on sinus volumetric and histometric changes after sinus floor augmentation compared to a conventional approach of non-biologic bone grafting materials. An electronic search of 4 databases (January 1990-February 2015), including PubMed/MEDLINE, EMBASE, Web of Science and Cochrane Central, and a hand search of peer-reviewed journals for relevant articles were performed. Human clinical trials with data on comparison of sinus volumetric and/or histometric outcomes with and without the use of rhBMP-2 in sinus grafting procedures, with ≥10 augmentation sites in each study group, and with a follow-up period of at least 6 months, were included. Random-effects meta-analyses were performed to analyze weighted mean difference (WMD) and confidence interval (CI) for the recorded variables according to PRISMA guidelines. Six randomized controlled trials (RCTs) were included. The results of the meta-analyses showed that the WMD of vertical bone height gain was -0.14 mm (95% CI = -1.91 to 1.62 mm, P = 0.87), the WMD of bone density was -142.42 mg/cm 3 (95% CI = -310.62-25.78 mg/cm 3 , P = 0.10), the WMD of the percentage of vital bone was -4.59% (95% CI = -11.73-2.56%, P = 0.21), and the WMD of the percentage of residual bone grafting materials was -9.90% (95% CI = -26.38-6.58%, P = 0.21). The comparison of implant survival rate presented an overall risk ratio of 1.00 (95% CI = 0.94-1.07). The two approaches (conventional bone grafting compared to BMPs) demonstrated comparable effectiveness for both clinical and histomorphometric measures. This systematic review revealed that the use of rhBMP-2 in maxillary sinus floor augmentation achieved similar clinical and histometric outcomes when compared to conventional sinus grafting procedures after a healing period of 6-9 months. However, previous studies showed the morbidity and other patient-reported outcomes were improved in rhBMP-2 approaches as compared to bone autograft procedures (both intraoral and extraoral bone harvesting because no donor site is required). Long-term studies are required to determine the cost-benefit of sinus floor augmentation procedures for patients requiring implant reconstruction. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. [Synthesis and characteristics of porous hydroxyapatite bioceramics].

    PubMed

    Niu, Jinlong; Zhang, Zhenxi; Jiang, Dazong

    2002-06-01

    The macroporous structure of human bone allows the ingrowth of the soft tissues and organic cells into the bone matrix, profits the development and metabolism of bone tissue, and adapts the bone to the change of load. There is great requirement for artificial biomimic porous bioactive ceramics with the similar structure of bone tissue that can be used clinically for repairing lost bone. Fine hydroxyapatite (HAp) powder produced by wet chemical reaction was mixed with hydrogen peroxide (H2O2), polyvinyl alcohol, methyl cellulose or other pores-making materials to form green cake. After drying at low temperature (below 100 degrees C) and decarbonizing at about 300 degrees C-400 degrees C, the spongy ceramic block was sintered at high temperature, thus, macroporous HAp bioceramic with interconnected pores and reasonable porosity and pore-diameter was manufactured. This kind of porous HAp bioceramics were intrinsically osteoinductive to a certain degree, but its outstanding property was that they can absorb human bone morphogenetic proteins and other bone growth factors to form composites, so that the macroporous HAp bioactive ceramic has appropriate feasibility for clinical application. From the point of biomedical application, the recent developments in synthesis and characteristics investigation of macroporous HAp are reviewed in this paper.

  1. Biomaterials with Antibacterial and Osteoinductive Properties to Repair Infected Bone Defects

    PubMed Central

    Lu, Haiping; Liu, Yi; Guo, Jing; Wu, Huiling; Wang, Jingxiao; Wu, Gang

    2016-01-01

    The repair of infected bone defects is still challenging in the fields of orthopedics, oral implantology and maxillofacial surgery. In these cases, the self-healing capacity of bone tissue can be significantly compromised by the large size of bone defects and the potential/active bacterial activity. Infected bone defects are conventionally treated by a systemic/local administration of antibiotics to control infection and a subsequent implantation of bone grafts, such as autografts and allografts. However, these treatment options are time-consuming and usually yield less optimal efficacy. To approach these problems, novel biomaterials with both antibacterial and osteoinductive properties have been developed. The antibacterial property can be conferred by antibiotics and other novel antibacterial biomaterials, such as silver nanoparticles. Bone morphogenetic proteins are used to functionalize the biomaterials with a potent osteoinductive property. By manipulating the carrying modes and release kinetics, these biomaterials are optimized to maximize their antibacterial and osteoinductive functions with minimized cytotoxicity. The findings, in the past decade, have shown a very promising application potential of the novel biomaterials with the dual functions in treating infected bone defects. In this review, we will summarize the current knowledge of novel biomaterials with both antibacterial and osteoinductive properties. PMID:26950123

  2. Biomaterials with Antibacterial and Osteoinductive Properties to Repair Infected Bone Defects.

    PubMed

    Lu, Haiping; Liu, Yi; Guo, Jing; Wu, Huiling; Wang, Jingxiao; Wu, Gang

    2016-03-03

    The repair of infected bone defects is still challenging in the fields of orthopedics, oral implantology and maxillofacial surgery. In these cases, the self-healing capacity of bone tissue can be significantly compromised by the large size of bone defects and the potential/active bacterial activity. Infected bone defects are conventionally treated by a systemic/local administration of antibiotics to control infection and a subsequent implantation of bone grafts, such as autografts and allografts. However, these treatment options are time-consuming and usually yield less optimal efficacy. To approach these problems, novel biomaterials with both antibacterial and osteoinductive properties have been developed. The antibacterial property can be conferred by antibiotics and other novel antibacterial biomaterials, such as silver nanoparticles. Bone morphogenetic proteins are used to functionalize the biomaterials with a potent osteoinductive property. By manipulating the carrying modes and release kinetics, these biomaterials are optimized to maximize their antibacterial and osteoinductive functions with minimized cytotoxicity. The findings, in the past decade, have shown a very promising application potential of the novel biomaterials with the dual functions in treating infected bone defects. In this review, we will summarize the current knowledge of novel biomaterials with both antibacterial and osteoinductive properties.

  3. Vitamin K2 stimulates osteoblastogenesis and suppresses osteoclastogenesis by suppressing NF-κB activation.

    PubMed

    Yamaguchi, Masayoshi; Weitzmann, M Neale

    2011-01-01

    Several bone protective factors are reported to exhibit stimulatory activities on bone formation coupled with inhibitory effects on bone resorption; one such factor is vitamin K2. Vitamin K species [K1 (phylloquinone) and K2 (menaquinone)] have long been associated with bone protective activities and are receiving intense interest as nutritional supplements for the prevention or amelioration of bone disease in humans. However, the mechanisms of vitamin K action on the skeleton are poorly defined. Activation of the nuclear factor κB (NF-κB) signal transduction pathway is essential for osteoclast formation and resorption. By contrast, NF-κB signaling potently antagonizes osteoblast differentiation and function, prompting us to speculate that NF-κB antagonists may represent a novel class of dual anti-catabolic and pro-anabolic agents. We now show that vitamin K2 action on osteoblast and osteoclast formation and activity is accomplished by down-regulating basal and cytokine-induced NF-κB activation, by increasing IκB mRNA, in a γ-carboxylation-independent manner. Furthermore, vitamin K2 prevented repression by tumor necrosis factor α (TNFα) of SMAD signaling induced by either transforming growth factor ß (TGFß) or bone morphogenetic protein-2 (BMP-2). Vitamin K2 further antagonized receptor activator of NF-κB (RANK) ligand (RANKL)-induced NF-κB activation in osteoclast precursors. Our data provide a novel mechanism to explain the dual pro-anabolic and anti-catabolic activities of vitamin K2, and may further support the concept that pharmacological modulation of NF-κB signal transduction may constitute an effective mechanism for ameliorating pathological bone loss and for promoting bone health.

  4. Controlled Retention of BMP-2-Derived Peptide on Nanofibers Based on Mussel-Inspired Adhesion for Bone Formation.

    PubMed

    Lee, Jinkyu; Perikamana, Sajeesh Kumar Madhurakkat; Ahmad, Taufiq; Lee, Min Suk; Yang, Hee Seok; Kim, Do-Gyoon; Kim, Kyobum; Kwon, Bosun; Shin, Heungsoo

    2017-04-01

    Although bone morphogenetic protein-2 (BMP-2) has been frequently used to stimulate bone formation, it has several side effects to be addressed, including the difficulty in optimization of clinically relevant doses and unwanted induction of cancerous signaling processes. In this study, an osteogenic peptide (OP) derived from BMP-2 was investigated as a substitute for BMP-2. In vitro studies showed that OP was able to enhance the osteogenic differentiation and mineralization of human mesenchymal stem cells (hMSCs). The peptides were then conjugated onto biocompatible poly-ι-lactide electrospun nanofibers through polydopamine chemistry. Surface chemical analysis proved that more than 80% of the peptides were stably retained on the nanofiber surface after 8 h of polydopamine coating during at least 28 days, and the amount of peptides that was retained increased depending on the polydopamine coating time. For instance, about 65% of the peptides were retained on nanofibers after 4 h of polydopamine coating. Also, a relatively small dose of peptides could effectively induce bone formation in in vivo critical-sized defects on the calvarial bones of mice. More than 50.4% ± 16.9% of newly formed bone was filled within the defect after treatment with only 10.5 ± 0.6 μg of peptides. Moreover, these groups had similar elastic moduli and contact hardnesses with host bone. Taken together, our results suggest that polydopamine-mediated OP immobilized on nanofibers can modulate the retention of relatively short lengths of peptides, which might make this an effective therapeutic remedy to guide bone regeneration using a relatively small amount of peptides.

  5. Local delivery of controlled-release simvastatin to improve the biocompatibility of polyethylene terephthalate artificial ligaments for reconstruction of the anterior cruciate ligament.

    PubMed

    Zhang, Peng; Han, Fei; Li, Yunxia; Chen, Jiwu; Chen, Tianwu; Zhi, Yunlong; Jiang, Jia; Lin, Chao; Chen, Shiyi; Zhao, Peng

    2016-01-01

    The Ligament Advanced Reinforcement System has recently been widely used as the primary graft of choice in anterior cruciate ligament (ACL) reconstruction. But the biological graft-bone healing still remains a problem. Previous studies have shown that simvastatin (SIM) stimulates bone formation. The objective of this study was to investigate whether surface coating with collagen containing low-dose SIM microsphere could enhance the surface biocompatibility of polyethylene terephthalate (PET) artificial ligaments to accelerate graft-to-bone healing. The in vitro studies demonstrated that bone marrow stromal cells on the collagen-coated PET scaffolds (COL/PET) and simvastatin/collagen-coated PET scaffolds (SIM/COL/PET) proliferated vigorously. Compared with the PET group and the COL/PET group, SIM could induce bone marrow stromal cells' osteoblastic differentiation, high alkaline phosphatase activity, more mineralization deposition, and more expression of osteoblast-related genes, such as osteocalcin, runt-related transcription factor 2, bone morphogenetic protein-2, and vascular endothelial growth factor, in the SIM/COL/PET group. In vivo, rabbits received ACL reconstruction with different scaffolds. Histological analysis demonstrated that graft-bone healing was significantly greater with angiogenesis and osteogenesis in the SIM/COL/PET group than the other groups. In addition, biomechanical testing at the eighth week demonstrated a significant increase in the ultimate failure load and stiffness in the SIM/COL/PET group. The low dose of SIM-sustained release from SIM/COL/PET promoted the graft-bone healing via its effect on both angiogenesis and osteogenesis. This study suggested that collagen containing low-dose SIM microsphere coating on the surface of PET artificial ligaments could be potentially applied for ACL reconstruction.

  6. Neurotrophin-3 Induces BMP-2 and VEGF Activities and Promotes the Bony Repair of Injured Growth Plate Cartilage and Bone in Rats.

    PubMed

    Su, Yu-Wen; Chung, Rosa; Ruan, Chun-Sheng; Chim, Shek Man; Kuek, Vincent; Dwivedi, Prem P; Hassanshahi, Mohammadhossein; Chen, Ke-Ming; Xie, Yangli; Chen, Lin; Foster, Bruce K; Rosen, Vicki; Zhou, Xin-Fu; Xu, Jiake; Xian, Cory J

    2016-06-01

    Injured growth plate is often repaired by bony tissue causing bone growth defects, for which the mechanisms remain unclear. Because neurotrophins have been implicated in bone fracture repair, here we investigated their potential roles in growth plate bony repair in rats. After a drill-hole injury was made in the tibial growth plate and bone, increased injury site mRNA expression was observed for neurotrophins NGF, BDNF, NT-3, and NT-4 and their Trk receptors. NT-3 and its receptor TrkC showed the highest induction. NT-3 was localized to repairing cells, whereas TrkC was observed in stromal cells, osteoblasts, and blood vessel cells at the injury site. Moreover, systemic NT-3 immunoneutralization reduced bone volume at injury sites and also reduced vascularization at the injured growth plate, whereas recombinant NT-3 treatment promoted bony repair with elevated levels of mRNA for osteogenic markers and bone morphogenetic protein (BMP-2) and increased vascularization and mRNA for vascular endothelial growth factor (VEGF) and endothelial cell marker CD31 at the injured growth plate. When examined in vitro, NT-3 promoted osteogenesis in rat bone marrow stromal cells, induced Erk1/2 and Akt phosphorylation, and enhanced expression of BMPs (particularly BMP-2) and VEGF in the mineralizing cells. It also induced CD31 and VEGF mRNA in rat primary endothelial cell culture. BMP activity appears critical for NT-3 osteogenic effect in vitro because it can be almost completely abrogated by co-addition of the BMP inhibitor noggin. Consistent with its angiogenic effect in vivo, NT-3 promoted angiogenesis in metatarsal bone explants, an effect abolished by co-treatment with anti-VEGF. This study suggests that NT-3 may be an osteogenic and angiogenic factor upstream of BMP-2 and VEGF in bony repair, and further studies are required to investigate whether NT-3 may be a potential target for preventing growth plate faulty bony repair or for promoting bone fracture healing. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.

  7. Freeze-Dried Platelet-Rich Plasma Accelerates Bone Union with Adequate Rigidity in Posterolateral Lumbar Fusion Surgery Model in Rats

    NASA Astrophysics Data System (ADS)

    Shiga, Yasuhiro; Orita, Sumihisa; Kubota, Go; Kamoda, Hiroto; Yamashita, Masaomi; Matsuura, Yusuke; Yamauchi, Kazuyo; Eguchi, Yawara; Suzuki, Miyako; Inage, Kazuhide; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Aoki, Yasuchika; Toyone, Tomoaki; Furuya, Takeo; Koda, Masao; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-11-01

    Fresh platelet-rich plasma (PRP) accelerates bone union in rat model. However, fresh PRP has a short half-life. We suggested freeze-dried PRP (FD-PRP) prepared in advance and investigated its efficacy in vivo. Spinal posterolateral fusion was performed on 8-week-old male Sprague-Dawley rats divided into six groups based on the graft materials (n = 10 per group): sham control, artificial bone (A hydroxyapatite-collagen composite) -alone, autologous bone, artificial bone + fresh-PRP, artificial bone + FD-PRP preserved 8 weeks, and artificial bone + human recombinant bone morphogenetic protein 2 (BMP) as a positive control. At 4 and 8 weeks after the surgery, we investigated their bone union-related characteristics including amount of bone formation, histological characteristics of trabecular bone at remodeling site, and biomechanical strength on 3-point bending. Comparable radiological bone union was confirmed at 4 weeks after surgery in 80% of the FD-PRP groups, which was earlier than in other groups (p < 0.05). Histologically, the trabecular bone had thinner and more branches in the FD-PRP. Moreover, the biomechanical strength was comparable to that of autologous bone. FD-PRP accelerated bone union at a rate comparable to that of fresh PRP and BMP by remodeling the bone with thinner, more tangled, and rigid trabecular bone.

  8. Freeze-Dried Platelet-Rich Plasma Accelerates Bone Union with Adequate Rigidity in Posterolateral Lumbar Fusion Surgery Model in Rats

    PubMed Central

    Shiga, Yasuhiro; Orita, Sumihisa; Kubota, Go; Kamoda, Hiroto; Yamashita, Masaomi; Matsuura, Yusuke; Yamauchi, Kazuyo; Eguchi, Yawara; Suzuki, Miyako; Inage, Kazuhide; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Aoki, Yasuchika; Toyone, Tomoaki; Furuya, Takeo; Koda, Masao; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-01-01

    Fresh platelet-rich plasma (PRP) accelerates bone union in rat model. However, fresh PRP has a short half-life. We suggested freeze-dried PRP (FD-PRP) prepared in advance and investigated its efficacy in vivo. Spinal posterolateral fusion was performed on 8-week-old male Sprague-Dawley rats divided into six groups based on the graft materials (n = 10 per group): sham control, artificial bone (A hydroxyapatite–collagen composite) –alone, autologous bone, artificial bone + fresh-PRP, artificial bone + FD-PRP preserved 8 weeks, and artificial bone + human recombinant bone morphogenetic protein 2 (BMP) as a positive control. At 4 and 8 weeks after the surgery, we investigated their bone union–related characteristics including amount of bone formation, histological characteristics of trabecular bone at remodeling site, and biomechanical strength on 3-point bending. Comparable radiological bone union was confirmed at 4 weeks after surgery in 80% of the FD-PRP groups, which was earlier than in other groups (p < 0.05). Histologically, the trabecular bone had thinner and more branches in the FD-PRP. Moreover, the biomechanical strength was comparable to that of autologous bone. FD-PRP accelerated bone union at a rate comparable to that of fresh PRP and BMP by remodeling the bone with thinner, more tangled, and rigid trabecular bone. PMID:27833116

  9. Cuscuta chinensis extract promotes osteoblast differentiation and mineralization in human osteoblast-like MG-63 cells.

    PubMed

    Yang, Hyun Mo; Shin, Hyun-Kyung; Kang, Young-Hee; Kim, Jin-Kyung

    2009-02-01

    The aim of the present study was to investigate whether the aqueous extract of To-Sa-Za (TSZ-AE), the seed of Cuscuta chinensis Lam., which is a traditional medicinal herb commonly used in Korea and other oriental countries, could induce osteogenic activity in human osteoblast-like MG-63 cells. TSZ-AE treatment mildly promoted the proliferation of MG-63 cells at doses of 500 and 1,000 microg/mL in the 24-hour culture period. Dose-dependent increases in alkaline phosphatase (ALP) activity and collagen synthesis were shown at 48 and 72 hours of incubation. The release of bone morphogenetic protein (BMP)-2 but not osteocalcin in the MG-63 cells was induced by TSZ-AE at 72 hours (100-1,000 microg/mL). In addition, TSZ-AE markedly increased mRNA expression of ALP, collagen, and BMP-2 in the MG-63 cells in a dose-dependent manner. Mineralization in the culture of MG-63 cells was significantly induced at 500 and 1,000 microg/mL TSZ-AE treatment. In conclusion, this study shows that TSZ-AE enhanced ALP activity, collagen synthesis, BMP-2 expression, and mineralization in MG-63 cells. These results strongly suggest that C. chinensis can play an important role in osteoblastic bone formation and may possibly lead to the development of bone-forming drugs.

  10. Bone substitutes: a review of their characteristics, clinical use, and perspectives for large bone defects management

    PubMed Central

    Fernandez de Grado, Gabriel; Keller, Laetitia; Idoux-Gillet, Ysia; Wagner, Quentin; Musset, Anne-Marie; Benkirane-Jessel, Nadia; Bornert, Fabien; Offner, Damien

    2018-01-01

    Bone replacement might have been practiced for centuries with various materials of natural origin, but had rarely met success until the late 19th century. Nowadays, many different bone substitutes can be used. They can be either derived from biological products such as demineralized bone matrix, platelet-rich plasma, hydroxyapatite, adjunction of growth factors (like bone morphogenetic protein) or synthetic such as calcium sulfate, tri-calcium phosphate ceramics, bioactive glasses, or polymer-based substitutes. All these substitutes are not suitable for every clinical use, and they have to be chosen selectively depending on their purpose. Thus, this review aims to highlight the principal characteristics of the most commonly used bone substitutes and to give some directions concerning their clinical use, as spine fusion, open-wedge tibial osteotomy, long bone fracture, oral and maxillofacial surgery, or periodontal treatments. However, the main limitations to bone substitutes use remain the management of large defects and the lack of vascularization in their central part, which is likely to appear following their utilization. In the field of bone tissue engineering, developing porous synthetic substitutes able to support a faster and a wider vascularization within their structure seems to be a promising way of research. PMID:29899969

  11. Biological effects of functionalizing copolymer scaffolds with nanodiamond particles.

    PubMed

    Xing, Zhe; Pedersen, Torbjorn O; Wu, Xujun; Xue, Ying; Sun, Yang; Finne-Wistrand, Anna; Kloss, Frank R; Waag, Thilo; Krueger, Anke; Steinmüller-Nethl, Doris; Mustafa, Kamal

    2013-08-01

    Significant evidence has indicated that poly(L-lactide)-co-(ɛ-caprolactone) [(poly(LLA-co-CL)] scaffolds could be one of the suitable candidates for bone tissue engineering. Oxygen-terminated nanodiamond particles (n-DP) were combined with poly(LLA-co-CL) and revealed to be positive for cell growth. In this study, we evaluated the influence of poly(LLA-co-CL) scaffolds modified by n-DP on attachment, proliferation, differentiation of bone marrow stromal cells (BMSCs) in vitro, and on bone formation using a sheep calvarial defect model. BMSCs were seeded on either poly(LLA-co-CL)- or n-DP-coated scaffolds and incubated for 1 h. Scanning electron microscopy (SEM) and fluorescence microscopy were used in addition to protein and DNA measurements to evaluate cellular attachment on the scaffolds. To determine the effect of n-DP on proliferation of BMSCs, cell/scaffold constructs were harvested after 3 days and evaluated by Bicinchoninic Acid (BCA) protein assay and SEM. In addition, the osteogenic differentiation of cells grown for 2 weeks on the various scaffolds and in a dynamic culture condition was evaluated by real-time RT-PCR. Unmodified and modified scaffolds were implanted into the calvaria of six-year-old sheep. The expression of collagen type I (COL I) and bone morphogenetic protein-2 (BMP-2) after 4 weeks as well as the formation of new bone after 12 and 24 weeks were analyzed by immunohistochemistry and histology. Scaffolds modified with n-DP supported increased cell attachment and the mRNA expression of osteopontin (OPN), bone sialoprotein (BSP), and BMP-2 were significantly increased after 2 weeks of culture. The BMSCs had spread well on the various scaffolds investigated after 3 days in the study with no significant difference in cell proliferation. Furthermore, the in vivo data revealed more positive staining of COL I and BMP-2 in relation to the n-DP-coated scaffolds after 4 weeks and presented more bone formation after 12 and 24 weeks. n-DP modification significantly increased cell attachment and differentiation of BMSCs on poly(LLA-co-CL) scaffolds in vitro and enhanced bone formation in vivo.

  12. [Bone fracture and the healing mechanisms. The role of BMP signaling in fracture healing].

    PubMed

    Imai, Yuuki; Takaoka, Kunio

    2009-05-01

    When bone tissue, which plays a central role in locomotive organs, is broken by trauma and decreased in its own function of support, it is lead to be remarkable decline in the activity of daily life (ADL). Recently, in a clinical situation, various treatments have been tried for prophylaxis of fractures, and these treatments have been rewarded with good results. However, fractures would be occurred in a certain amount and there would be serious problems in ADL if the treatment fails to repair fractures. Furthermore, fractures could spontaneously heal in several weeks, it can be achieved in early rehabilitation and improvement of ADL, if we can accelerate fracture healing. Bone morphogenetic proteins, which were advocated by Dr. Urist, would be expected to be a key to establish much better society especially for the old.

  13. 3-Dimensional functionalized polycaprolactone-hyaluronic acid hydrogel constructs for bone tissue engineering.

    PubMed

    Hamlet, Stephen M; Vaquette, Cedryck; Shah, Amit; Hutmacher, Dietmar W; Ivanovski, Saso

    2017-04-01

    Alveolar bone regeneration remains a significant clinical challenge in periodontology and dental implantology. This study assessed the mineralized tissue forming potential of 3-D printed medical grade polycaprolactone (mPCL) constructs containing osteoblasts (OB) encapsulated in a hyaluronic acid (HA)-hydrogel incorporating bone morphogenetic protein-7 (BMP-7). HA-hydrogels containing human OB ± BMP-7 were prepared. Cell viability, osteogenic gene expression, mineralized tissue formation and BMP-7 release in vitro, were assessed by fluorescence staining, RT-PCR, histological/μ-CT examination and ELISA respectively. In an athymic rat model, subcutaneous ectopic mineralized tissue formation in mPCL-hydrogel constructs was assessed by μ-CT and histology. Osteoblast encapsulation in HA-hydrogels did not detrimentally effect cell viability, and 3-D culture in osteogenic media showed mineralized collagenous matrix formation after 6 weeks. BMP-7 release from the hydrogel was biphasic, sustained and increased osteogenic gene expression in vitro. After 4 weeks in vivo, mPCL-hydrogel constructs containing BMP-7 formed significantly more volume (mm 3 ) of vascularized bone-like tissue. Functionalized mPCL-HA hydrogel constructs provide a favourable environment for bone tissue engineering. Although encapsulated cells contributed to mineralized tissue formation within the hydrogel in vitro and in vivo, their addition did not result in an improved outcome compared to BMP-7 alone. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Action Mechanism of Fibroblast Growth Factor-2 (FGF-2) in the Promotion of Periodontal Regeneration in Beagle Dogs

    PubMed Central

    Nagayasu-Tanaka, Toshie; Anzai, Jun; Takaki, Shu; Shiraishi, Noriko; Terashima, Akio; Asano, Taiji; Nozaki, Takenori; Kitamura, Masahiro; Murakami, Shinya

    2015-01-01

    Fibroblast growth factor-2 (FGF-2) enhances the formation of new alveolar bone, cementum, and periodontal ligament (PDL) in periodontal defect models. However, the mechanism through which FGF-2 acts in periodontal regeneration in vivo has not been fully clarified yet. To reveal the action mechanism, the formation of regenerated tissue and gene expression at the early phase were analyzed in a beagle dog 3-wall periodontal defect model. FGF-2 (0.3%) or the vehicle (hydroxypropyl cellulose) only were topically applied to the defect in FGF-2 and control groups, respectively. Then, the amount of regenerated tissues and the number of proliferating cells at 3, 7, 14, and 28 days and the number of blood vessels at 7 days were quantitated histologically. Additionally, the expression of osteogenic genes in the regenerated tissue was evaluated by real-time PCR at 7 and 14 days. Compared with the control, cell proliferation around the existing bone and PDL, connective tissue formation on the root surface, and new bone formation in the defect at 7 days were significantly promoted by FGF-2. Additionally, the number of blood vessels at 7 days was increased by FGF-2 treatment. At 28 days, new cementum and PDL were extended by FGF-2. Moreover, FGF-2 increased the expression of bone morphogenetic protein 2 (BMP-2) and osteoblast differentiation markers (osterix, alkaline phosphatase, and osteocalcin) in the regenerated tissue. We revealed the facilitatory mechanisms of FGF-2 in periodontal regeneration in vivo. First, the proliferation of fibroblastic cells derived from bone marrow and PDL was accelerated and enhanced by FGF-2. Second, angiogenesis was enhanced by FGF-2 treatment. Finally, osteoblastic differentiation and bone formation, at least in part due to BMP-2 production, were rapidly induced by FGF-2. Therefore, these multifaceted effects of FGF-2 promote new tissue formation at the early regeneration phase, leading to enhanced formation of new bone, cementum, and PDL. PMID:26120833

  15. Chronology and regulation of gene expression of RANKL in the rat dental follicle.

    PubMed

    Liu, D; Yao, S; Pan, F; Wise, G E

    2005-10-01

    Tooth eruption in the rat requires bone resorption resulting from a major burst of osteoclastogenesis on postnatal day 3 and a minor burst of osteoclastogenesis on postnatal day 10 in the alveolar bone of the first mandibular molar. The dental follicle regulates the major burst on postnatal day 3 by down-regulating its osteoprotegerin (OPG) gene expression to enable osteoclastogenesis to occur. To determine the role of receptor activator of nuclear factor-kappa B ligand (RANKL) in tooth eruption, its gene expression was measured on postnatal days 1-11 in the dental follicle. The results show that RANKL expression was significantly elevated on postnatal days 9-11 in comparison to low expression levels at earlier time-points. As OPG expression is high at this latter time-point, this increase in RANKL expression would be needed for stimulating the minor burst of osteoclastogenesis. Tumor necrosis factor-alpha enhances RANKL gene expression in vitro and it may be responsible for up-regulating RANKL in vivo. Transforming growth factor-beta1 and interleukin-1alpha also enhance RANKL gene expression in vitro but probably have no effect in vivo because they are maximally expressed early. Bone morphogenetic protein-2 acts to down-regulate RANKL expression in vitro and, in vivo, may promote alveolar bone growth in the basal region of the tooth.

  16. Addition of bone morphogenetic protein type 2 to ascorbate and β-glycerophosphate supplementation did not enhance osteogenic differentiation of human adipose-derived stem cells.

    PubMed

    Cruz, Ariadne Cristiane Cabral; Silva, Mariana Lúcia; Caon, Thiago; Simões, Cláudia Maria Oliveira

    2012-01-01

    Bone morphogenetic protein type 2 (BMP-2) is a potent local factor, which promotes bone formation and has been used as an osteogenic supplement for mesenchymal stem cells. This study evaluated the effect of a recombinant BMP-2 as well as the endogenous BMP-4 and BMP-7 in the osteogenic differentiation of adipose-derived stem cells (ASCs) in medium supplemented with ascorbate and β-glycerophosphate. Human ASCs were treated with osteogenic medium in the presence (ASCs+OM+BMP-2) or absence (ASCs+OM) of BMP-2. The alkaline phosphatase (ALP) activity was determined and the extracellular matrix mineralization was evaluated by Von Kossa staining and calcium quantification. The expressions of BMP-4, BMP-7, Smad1, Smad4, and phosphorylated Smad1/5/8 were analyzed by western blotting. Relative mRNA expressions of Smad1, BMP receptor type II (BMPR-II), osteonectin, and osteocalcin were evaluated by qPCR. ASCs+OM demonstrated the highest expression of BMP-4 and BMP-7 at days 21 and 7, respectively, the highest levels of BMPR-II mRNA expression at day 28, and the highest levels of Smad1 mRNA at days 14 and 28. ASCs+OM+BMP-2 demonstrated the highest levels of Smad1 mRNA expression at days 1, 7, and 21, the highest expression of Smad1 at day 7, the highest expression of Smad4 at day 14, the highest ALP activity at days 14 and 21, and expression of phosphorylated Smad1/5/8 at day 7. ASCs+OM and ASCs+OM+BMP2 showed similar ALP activity at days 7 and 28, similar osteonectin and osteocalcin mRNA expression at all time periods, and similar calcium depositions at all time periods. We concluded that human ASCs expressed endogenous BMP-4 and BMP-7. Moreover, the supplementation of ASCs with BMP-2 did not increase the level of osteogenic markers in the initial (ALP activity), intermediate (osteonectin and osteocalcin), or final (calcium deposition) phases, suggesting that the exogenous addition of BMP-2 did not improve the in vitro osteogenesis process of human ASCs.

  17. Directly auto-transplanted mesenchymal stem cells induce bone formation in a ceramic bone substitute in an ectopic sheep model

    PubMed Central

    Boos, Anja M; Loew, Johanna S; Deschler, Gloria; Arkudas, Andreas; Bleiziffer, Oliver; Gulle, Heinz; Dragu, Adrian; Kneser, Ulrich; Horch, Raymund E; Beier, Justus P

    2011-01-01

    Abstract Bone tissue engineering approaches increasingly focus on the use of mesenchymal stem cells (MSC). In most animal transplantation models MSC are isolated and expanded before auto cell transplantation which might be critical for clinical application in the future. Hence this study compares the potential of directly auto-transplanted versus in vitro expanded MSC with or without bone morphogenetic protein-2 (BMP-2) to induce bone formation in a large volume ceramic bone substitute in the sheep model. MSC were isolated from bone marrow aspirates and directly auto-transplanted or expanded in vitro and characterized using fluorescence activated cell sorting (FACS) and RT-PCR analysis before subcutaneous implantation in combination with BMP-2 and β-tricalcium phosphate/hydroxyapatite (β-TCP/HA) granules. Constructs were explanted after 1 to 12 weeks followed by histological and RT-PCR evaluation. Sheep MSC were CD29+, CD44+ and CD166+ after selection by Ficoll gradient centrifugation, while directly auto-transplanted MSC-populations expressed CD29 and CD166 at lower levels. Both, directly auto-transplanted and expanded MSC, were constantly proliferating and had a decreasing apoptosis over time in vivo. Directly auto-transplanted MSC led to de novo bone formation in a heterotopic sheep model using a β-TCP/HA matrix comparable to the application of 60 μg/ml BMP-2 only or implantation of expanded MSC. Bone matrix proteins were up-regulated in constructs following direct auto-transplantation and in expanded MSC as well as in BMP-2 constructs. Up-regulation was detected using immunohistology methods and RT-PCR. Dense vascularization was demonstrated by CD31 immunohistology staining in all three groups. Ectopic bone could be generated using directly auto-transplanted or expanded MSC with β-TCP/HA granules alone. Hence BMP-2 stimulation might become dispensable in the future, thus providing an attractive, clinically feasible approach to bone tissue engineering. PMID:20636333

  18. Interconnected porous hydroxyapatite ceramics for bone tissue engineering

    PubMed Central

    Yoshikawa, Hideki; Tamai, Noriyuki; Murase, Tsuyoshi; Myoui, Akira

    2008-01-01

    Several porous calcium hydroxyapatite (HA) ceramics have been used clinically as bone substitutes, but most of them possessed few interpore connections, resulting in pathological fracture probably due to poor bone formation within the substitute. We recently developed a fully interconnected porous HA ceramic (IP-CHA) by adopting the ‘foam-gel’ technique. The IP-CHA had a three-dimensional structure with spherical pores of uniform size (average 150 μm, porosity 75%), which were interconnected by window-like holes (average diameter 40 μm), and also demonstrated adequate compression strength (10–12 MPa). In animal experiments, the IP-CHA showed superior osteoconduction, with the majority of pores filled with newly formed bone. The interconnected porous structure facilitates bone tissue engineering by allowing the introduction of mesenchymal cells, osteotropic agents such as bone morphogenetic protein or vasculature into the pores. Clinically, we have applied the IP-CHA to treat various bony defects in orthopaedic surgery, and radiographic examinations demonstrated that grafted IP-CHA gained radiopacity more quickly than the synthetic HA in clinical use previously. We review the accumulated data on bone tissue engineering using the novel scaffold and on clinical application in the orthopaedic field. PMID:19106069

  19. Time-sequential changes of differentially expressed miRNAs during the process of anterior lumbar interbody fusion using equine bone protein extract, rhBMP-2 and autograft

    NASA Astrophysics Data System (ADS)

    Chen, Da-Fu; Zhou, Zhi-Yu; Dai, Xue-Jun; Gao, Man-Man; Huang, Bao-Ding; Liang, Tang-Zhao; Shi, Rui; Zou, Li-Jin; Li, Hai-Sheng; Bünger, Cody; Tian, Wei; Zou, Xue-Nong

    2014-03-01

    The precise mechanism of bone regeneration in different bone graft substitutes has been well studied in recent researches. However, miRNAs regulation of the bone formation has been always mysterious. We developed the anterior lumbar interbody fusion (ALIF) model in pigs using equine bone protein extract (BPE), recombinant human bone morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS), and autograft as bone graft substitute, respectively. The miRNA and gene expression profiles of different bone graft materials were examined using microarray technology and data analysis, including self-organizing maps, KEGG pathway and Biological process GO analyses. We then jointly analyzed miRNA and mRNA profiles of the bone fusion tissue at different time points respectively. Results showed that miRNAs, including let-7, miR-129, miR-21, miR-133, miR-140, miR-146, miR-184, and miR-224, were involved in the regulation of the immune and inflammation response, which provided suitable inflammatory microenvironment for bone formation. At late stage, several miRNAs directly regulate SMAD4, Estrogen receptor 1 and 5-hydroxytryptamine (serotonin) receptor 2C for bone formation. It can be concluded that miRNAs play important roles in balancing the inflammation and bone formation.

  20. Bioactive Molecule-loaded Drug Delivery Systems to Optimize Bone Tissue Repair.

    PubMed

    Oshiro, Joao Augusto; Sato, Mariana Rillo; Scardueli, Cassio Rocha; Lopes de Oliveira, Guilherme Jose Pimentel; Abucafy, Marina Paiva; Chorilli, Marlus

    2017-01-01

    Bioactive molecules such as peptides and proteins can optimize the repair of bone tissue; however, the results are often unpredictable when administered alone, owing to their short biological half-life and instability. Thus, the development of bioactive molecule-loaded drug delivery systems (DDS) to repair bone tissue has been the subject of intense research. DDS can optimize the repair of bone tissue owing to their physicochemical properties, which improve cellular interactions and enable the incorporation and prolonged release of bioactive molecules. These characteristics are fundamental to favor bone tissue homeostasis, since the biological activity of these factors depends on how accessible they are to the cell. Considering the importance of these DDS, this review aims to present relevant information on DDS when loaded with osteogenic growth peptide and bone morphogenetic protein. These are bioactive molecules that are capable of modulating the differentiation and proliferation of mesenchymal cells in bone tissue cells. Moreover, we will present different approaches using these peptide and protein-loaded DDS, such as synthetic membranes and scaffolds for bone regeneration, synthetic grafts, bone cements, liposomes, and micelles, which aim at improving the therapeutic effectiveness, and we will compare their advantages with commercial systems. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  1. Novel osteoinductive photo-cross-linkable chitosan-lactide-fibrinogen hydrogels enhance bone regeneration in critical size segmental bone defects

    PubMed Central

    Kim, Sungwoo; Bedigrew, Katherine; Guda, Teja; Maloney, William J.; Park, Sangwon; Wenke, Joseph C.; Yang, Yunzhi Peter

    2014-01-01

    The purpose of this study was to develop and characterize a novel photo-cross-linkable chitosan-lactide-fibrinogen (CLF) hydrogel and evaluate the efficacy of bone morphogenetic protein-2 (BMP-2) containing CLF hydrogel for osteogenesis in vitro and in vivo. We synthesized the CLF hydrogels and characterized their chemical structure, degradation rate, compressive modulus, and in vitro BMP-2 release kinetics. We evaluated bioactivities of the BMP-2 containing CLF hydrogels (0, 50, 100, and 500 ng/ml) in vitro using W-20-17 preosteoblast mouse bone marrow stromal cells and C2C12 mouse myoblast cells. The effect of BMP-2 containing CLF gels (0, 0.5, 1, 2, and 5μg) on bone formation was evaluated using rat critical size segmental bone defects for 4 weeks. FTIR spectra and SEM images showed chemical and structural changes by addition of fibrinogen into chitosan-lactide copolymer. Incorporation of fibrinogen molecules significantly increased compressive modulus of the hydrogels. In vitro BMP-2 release study showed initial burst releases from the CLF hydrogels followed by sustained releases, regardless of the concentration of the BMP-2 over 4 weeks. Cells in all groups were viable in the presence of the hydrogels regardless of BMP-2 doses, indicating non-cytotoxicity of hydrogels. Alkaline phosphate activity and mineralization of cells exhibited dose dependence on BMP-2 containing CLF hydrogels. Radiographs, microcomputed tomography, and histology confirmed that the BMP-2 containing CLF hydrogels prompted neo-osteogenesis and accelerated healing of the defects in a dose-dependent manner. Thus the CLF hydrogel is a promising delivery system of growth factors for bone regeneration. PMID:25174669

  2. A composite mouse model of aplastic anemia complicated with iron overload

    PubMed Central

    Wu, Dijiong; Wen, Xiaowen; Liu, Wenbin; Xu, Linlong; Ye, Baodong; Zhou, Yuhong

    2018-01-01

    Iron overload is commonly encountered during the course of aplastic anemia (AA), but no composite animal model has been developed yet, which hinders drug research. In the present study, the optimal dosage and duration of intraperitoneal iron dextran injection for the development of an iron overload model in mice were explored. A composite model of AA was successfully established on the principle of immune-mediated bone marrow failure. Liver volume, peripheral hemogram, bone marrow pathology, serum iron, serum ferritin, pathological iron deposition in multiple organs (liver, bone marrow, spleen), liver hepcidin, and bone morphogenetic protein 6 (BMP6), SMAD family member 4 (SMAD4) and transferrin receptor 2 (TfR2) mRNA expression levels were compared among the normal control, AA, iron overload and composite model groups to validate the composite model, and explore the pathogenesis and features of iron overload in this model. The results indicated marked increases in iron deposits, with significantly increased liver/body weight ratios as well as serum iron and ferritin in the iron overload and composite model groups as compared with the normal control and AA groups (P<0.05). There were marked abnormalities in iron regulation gene expression between the AA and composite model groups, as seen by the significant decrease of hepcidin expression in the liver (P<0.01) that paralleled the changes in BMP6, SMAD4, and TfR2. In summary, a composite mouse model with iron overload and AA was successfully established, and AA was indicated to possibly have a critical role in abnormal iron metabolism, which promoted the development of iron deposits. PMID:29434729

  3. A composite mouse model of aplastic anemia complicated with iron overload.

    PubMed

    Wu, Dijiong; Wen, Xiaowen; Liu, Wenbin; Xu, Linlong; Ye, Baodong; Zhou, Yuhong

    2018-02-01

    Iron overload is commonly encountered during the course of aplastic anemia (AA), but no composite animal model has been developed yet, which hinders drug research. In the present study, the optimal dosage and duration of intraperitoneal iron dextran injection for the development of an iron overload model in mice were explored. A composite model of AA was successfully established on the principle of immune-mediated bone marrow failure. Liver volume, peripheral hemogram, bone marrow pathology, serum iron, serum ferritin, pathological iron deposition in multiple organs (liver, bone marrow, spleen), liver hepcidin, and bone morphogenetic protein 6 (BMP6), SMAD family member 4 (SMAD4) and transferrin receptor 2 (TfR2) mRNA expression levels were compared among the normal control, AA, iron overload and composite model groups to validate the composite model, and explore the pathogenesis and features of iron overload in this model. The results indicated marked increases in iron deposits, with significantly increased liver/body weight ratios as well as serum iron and ferritin in the iron overload and composite model groups as compared with the normal control and AA groups (P<0.05). There were marked abnormalities in iron regulation gene expression between the AA and composite model groups, as seen by the significant decrease of hepcidin expression in the liver (P<0.01) that paralleled the changes in BMP6, SMAD4, and TfR2. In summary, a composite mouse model with iron overload and AA was successfully established, and AA was indicated to possibly have a critical role in abnormal iron metabolism, which promoted the development of iron deposits.

  4. Bone marrow concentrate promotes bone regeneration with a suboptimal-dose of rhBMP-2.

    PubMed

    Egashira, Kazuhiro; Sumita, Yoshinori; Zhong, Weijian; I, Takashi; Ohba, Seigo; Nagai, Kazuhiro; Asahina, Izumi

    2018-01-01

    Bone marrow concentrate (BMC), which is enriched in mononuclear cells (MNCs) and platelets, has recently attracted the attention of clinicians as a new optional means for bone engineering. We previously reported that the osteoinductive effect of bone morphogenetic protein-2 (BMP-2) could be enhanced synergistically by co-transplantation of peripheral blood (PB)-derived platelet-rich plasma (PRP). This study aims to investigate whether BMC can effectively promote bone formation induced by low-dose BMP-2, thereby reducing the undesirable side-effects of BMP-2, compared to PRP. Human BMC was obtained from bone marrow aspirates using an automated blood separator. The BMC was then seeded onto β-TCP granules pre-adsorbed with a suboptimal-dose (minimum concentration to induce bone formation at 2 weeks in mice) of recombinant human (rh) BMP-2. These specimens were transplanted subcutaneously to the dorsal skin of immunodeficient-mice and the induction of ectopic bone formation was assessed 2 and 4 weeks post-transplantation. Transplantations of five other groups [PB, PRP, platelet-poor plasma (PPP), bone marrow aspirate (BM), and BM-PPP] were employed as experimental controls. Then, to clarify the effects on vertical bone augmentation, specimens from the six groups were transplanted for on-lay placement on the craniums of mice. The results indicated that BMC, which contained an approximately 2.5-fold increase in the number of MNCs compared to PRP, could accelerate ectopic bone formation until 2 weeks post-transplantation. On the cranium, the BMC group promoted bone augmentation with a suboptimal-dose of rhBMP-2 compared to other groups. Particularly in the BMC specimens harvested at 4 weeks, we observed newly formed bone surrounding the TCP granules at sites far from the calvarial bone. In conclusion, the addition of BMC could reduce the amount of rhBMP-2 by one-half via its synergistic effect on early-phase osteoinduction. We propose here that BMC transplantation facilitates the clinical use of rhBMP-2 as an alternative strategy for bone engineering.

  5. Bone marrow concentrate promotes bone regeneration with a suboptimal-dose of rhBMP-2

    PubMed Central

    Egashira, Kazuhiro; Zhong, Weijian; I, Takashi; Ohba, Seigo; Nagai, Kazuhiro; Asahina, Izumi

    2018-01-01

    Bone marrow concentrate (BMC), which is enriched in mononuclear cells (MNCs) and platelets, has recently attracted the attention of clinicians as a new optional means for bone engineering. We previously reported that the osteoinductive effect of bone morphogenetic protein-2 (BMP-2) could be enhanced synergistically by co-transplantation of peripheral blood (PB)-derived platelet-rich plasma (PRP). This study aims to investigate whether BMC can effectively promote bone formation induced by low-dose BMP-2, thereby reducing the undesirable side-effects of BMP-2, compared to PRP. Human BMC was obtained from bone marrow aspirates using an automated blood separator. The BMC was then seeded onto β-TCP granules pre-adsorbed with a suboptimal-dose (minimum concentration to induce bone formation at 2 weeks in mice) of recombinant human (rh) BMP-2. These specimens were transplanted subcutaneously to the dorsal skin of immunodeficient-mice and the induction of ectopic bone formation was assessed 2 and 4 weeks post-transplantation. Transplantations of five other groups [PB, PRP, platelet-poor plasma (PPP), bone marrow aspirate (BM), and BM-PPP] were employed as experimental controls. Then, to clarify the effects on vertical bone augmentation, specimens from the six groups were transplanted for on-lay placement on the craniums of mice. The results indicated that BMC, which contained an approximately 2.5-fold increase in the number of MNCs compared to PRP, could accelerate ectopic bone formation until 2 weeks post-transplantation. On the cranium, the BMC group promoted bone augmentation with a suboptimal-dose of rhBMP-2 compared to other groups. Particularly in the BMC specimens harvested at 4 weeks, we observed newly formed bone surrounding the TCP granules at sites far from the calvarial bone. In conclusion, the addition of BMC could reduce the amount of rhBMP-2 by one-half via its synergistic effect on early-phase osteoinduction. We propose here that BMC transplantation facilitates the clinical use of rhBMP-2 as an alternative strategy for bone engineering. PMID:29346436

  6. Bone Regeneration from PLGA Micro-Nanoparticles

    PubMed Central

    Ortega-Oller, Inmaculada; Galindo-Moreno, Pablo; Jódar-Reyes, Ana Belén; Peula-García, Jose Manuel

    2015-01-01

    Poly-lactic-co-glycolic acid (PLGA) is one of the most widely used synthetic polymers for development of delivery systems for drugs and therapeutic biomolecules and as component of tissue engineering applications. Its properties and versatility allow it to be a reference polymer in manufacturing of nano- and microparticles to encapsulate and deliver a wide variety of hydrophobic and hydrophilic molecules. It additionally facilitates and extends its use to encapsulate biomolecules such as proteins or nucleic acids that can be released in a controlled way. This review focuses on the use of nano/microparticles of PLGA as a delivery system of one of the most commonly used growth factors in bone tissue engineering, the bone morphogenetic protein 2 (BMP2). Thus, all the needed requirements to reach a controlled delivery of BMP2 using PLGA particles as a main component have been examined. The problems and solutions for the adequate development of this system with a great potential in cell differentiation and proliferation processes under a bone regenerative point of view are discussed. PMID:26509156

  7. Site-Directed Immobilization of Bone Morphogenetic Protein 2 to Solid Surfaces by Click Chemistry.

    PubMed

    Siverino, Claudia; Tabisz, Barbara; Lühmann, Tessa; Meinel, Lorenz; Müller, Thomas; Walles, Heike; Nickel, Joachim

    2018-03-29

    Different therapeutic strategies for the treatment of non-healing long bone defects have been intensively investigated. Currently used treatments present several limitations that have led to the use of biomaterials in combination with osteogenic growth factors, such as bone morphogenetic proteins (BMPs). Commonly used absorption or encapsulation methods require supra-physiological amounts of BMP2, typically resulting in a so-called initial burst release effect that provokes several severe adverse side effects. A possible strategy to overcome these problems would be to covalently couple the protein to the scaffold. Moreover, coupling should be performed in a site-specific manner in order to guarantee a reproducible product outcome. Therefore, we created a BMP2 variant, in which an artificial amino acid (propargyl-L-lysine) was introduced into the mature part of the BMP2 protein by codon usage expansion (BMP2-K3Plk). BMP2-K3Plk was coupled to functionalized beads through copper catalyzed azide-alkyne cycloaddition (CuAAC). The biological activity of the coupled BMP2-K3Plk was proven in vitro and the osteogenic activity of the BMP2-K3Plk-functionalized beads was proven in cell based assays. The functionalized beads in contact with C2C12 cells were able to induce alkaline phosphatase (ALP) expression in locally restricted proximity of the bead. Thus, by this technique, functionalized scaffolds can be produced that can trigger cell differentiation towards an osteogenic lineage. Additionally, lower BMP2 doses are sufficient due to the controlled orientation of site-directed coupled BMP2. With this method, BMPs are always exposed to their receptors on the cell surface in the appropriate orientation, which is not the case if the factors are coupled via non-site-directed coupling techniques. The product outcome is highly controllable and, thus, results in materials with homogeneous properties, improving their applicability for the repair of critical size bone defects.

  8. Osteoblast Role in Rheumatic Diseases.

    PubMed

    Corrado, Addolorata; Maruotti, Nicola; Cantatore, Francesco Paolo

    2017-06-15

    Alterations in osteoblast growth, differentiation and activity play a role in the pathogenesis of several rheumatic diseases, such as rheumatoid arthritis, spondyloarthritides, osteoarthritis, and osteoporosis. In fact, in these rheumatic diseases, abnormal activity of Wnt signaling, receptor activator of nuclear factor-κB (RANK)-RANK ligand (RANKL)-osteoprotegerin (OPG) signaling, bone morphogenetic proteins (BMPs) pathway and other mechanisms have been described in osteoblasts. This review article is focused on current knowledge on the role of osteoblast dysregulation occurring in rheumatic diseases.

  9. Beyond Osteogenesis: An in vitro Comparison of the Potentials of Six Bone Morphogenetic Proteins

    DTIC Science & Technology

    2013-10-01

    therapy . To date the majority of studies comparing BMPs have focused on the direct osteogenic effects of the different BMPs utilizing cells with...regards to the osteogenic differentiation of human MSCs (Friedman et al., 2006). Although their study did not include BMP-9, our results are in...the spectrum of potential applications for BMPs, the objective of this study was to evaluate various BMPs under a variety of conditions to provide

  10. Association of BDNF and BMPR1A with clinicopathologic parameters in benign and malignant gallbladder lesions

    PubMed Central

    2013-01-01

    Background Neurotrophic factors such as brain derived neurotrophic factor (BDNF) are synthesized in a variety of neural and non-neuronal cell types and regulate survival, proliferation and apoptosis. In addition, bone morphogenetic proteins (BMPs) inhibit the proliferation of pulmonary large carcinoma cells bone morphogenetic protein receptor, type IA (BMPR1A). Little is known about the expression of BDNF or BMPR1A in malignant gall bladder lesions. This study was to evaluate BDNF and BMPR1A expression and evaluate the clinicopathological significance in benign and malignant lesions of the gallbladder. Methods The BDNF and BMPR1A expression of gallbladder adenocarcinoma, peritumoral tissues, adenoma, polyp and chronic cholecystitis were Immunohistochemically determined. Results BDNF expression was significantly higher in gallbladder adenocarcinoma than in peritumoral tissues, adenoma, polyps and chronic cholecystitis samples. However, BMPR1A expression was significantly lower in gallbladder adenocarcinoma than in peritumoral tissues, adenomas, polyps and chronic cholecystitis tissues. The specimens with increased expression of BDNF in the benign lesions exhibited moderate- or severe-dysplasia of gallbladder epithelium. BDNF expression was significantly lower in well-differentiated adenocarcinomas with maximum tumor diameter <2 cm, no metastasis to lymph nodes, and no invasion of regional tissues compared to poorly-differentiated adenocarcinomas with maximal tumor diameter >2 cm, metastasis of lymph node, and invasiveness of regional tissues in gallbladder adenocarcinoma. BMPR1A expression were significantly higher in the well-differentiated adenocarcinoma with maximal tumor diameter <2 cm, no metastasis of lymph node, and no invasion of regional tissues compared to poorly-differentiated adenocarcinomas with maximal tumor diameter >2 cm, metastasis of lymph node, and invasiveness of regional tissues in gallbladder. Univariate Kaplan-Meier analysis indicated increased expression of BDNF or decreased expression of BMPR1A was associated with decreased disease specific survival (DSS) rates. Similarly, multivariate Cox regression analysis showed increased expression of BDNF or decreased expression of BMPR1A are independent predictors of poor DSS rates in gallbladder adenocarcinoma. Conclusions In gallbladder malignancies, the increased expression of BDNF and decreased expression of BMPR1A were associated with increased risk of metastasis, regional invasion and mortality. They might serve as novel indicators of gallbladder adenocarcinoma outcomes, which may prove valuable for the development of personalized therapeutic paradigms. PMID:23531103

  11. Minimally Invasive Transforaminal Lumbar Interbody Fusion: Meta-analysis of the Fusion Rates. What is the Optimal Graft Material?

    PubMed

    Parajón, Avelino; Alimi, Marjan; Navarro-Ramirez, Rodrigo; Christos, Paul; Torres-Campa, Jose M; Moriguchi, Yu; Lang, Gernot; Härtl, Roger

    2017-12-01

    Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is an increasingly popular procedure with several potential advantages over traditional open TLIF. The current study aimed to compare fusion rates of different graft materials used in MIS-TLIF, via meta-analysis of the published literature. A Medline search was performed and a database was created including patient's type of graft, clinical outcome, fusion rate, fusion assessment modality, and duration of follow-up. Meta-analysis of the fusion rate was performed using StatsDirect software (StatsDirect Ltd, Cheshire, United Kingdom). A total of 1533 patients from 40 series were included. Fusion rates were high, ranging from 91.8% to 99%. The imaging modalities used to assess fusion were computed tomography scans (30%) and X-rays (70%). Comparison of all recombinant human bone morphogenetic protein (rhBMP) series with all non-rhBMP series showed fusion rates of 96.6% and 92.5%, respectively. The lowest fusion rate was seen with isolated use of autologous local bone (91.8%). The highest fusion rate was observed with combination of autologous local bone with bone extender and rhBMP (99.1%). The highest fusion rate without the use of BMP was seen with autologous local bone + bone extender (93.1%). The reported complication rate ranged from 0% to 35.71%. Clinical improvement was observed in all studies. Fusion rates are generally high with MIS-TLIF regardless of the graft material used. Given the potential complications of iliac bone harvesting and rhBMP, use of other bone graft options for MIS-TLIF is reasonable. The highest fusion rate without the use of rhBMP was seen with autologous local bone plus bone extender (93.1%). Published by Oxford University Press on behalf of Congress of Neurological Surgeons 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  12. Comparison between various densities of pore titanium meshes and e-polytetrafluoroethylene (ePTFE) membrane regarding bone regeneration induced by low intensity pulsed ultrasound (LIPUS) in rabbit nasal bone.

    PubMed

    Higuchi, Masatoshi; Moroi, Akinori; Yoshizawa, Kunio; Kosaka, Akihiko; Ikawa, Hiroumi; Iguchi, Ran; Saida, Yuriko; Hotta, Asami; Tsutsui, Takamitsu; Ueki, Koichiro

    2016-09-01

    The purpose of this study was to compare bone regenerative capability following use of polytetrafluoroethylene (ePTFE) membrane against that when various densities of pore titanium meshes are used with and without low intensity pulsed ultrasound (LIPUS). Adult male white rabbits were divided into 8 groups. In 4 groups, after incising along the nasal bone, four 3 × 8 mm bone defects were made in both sides and covered by an ePTFE membrane (group E: n = 15), a high density pore titanium mesh (group H: n = 15), a low density pore titanium mesh (group L: n = 15), and no mesh (control) (group C: n = 15). Furthermore, LIPUS was irradiated after surgery in 4 groups (groups EL, HL, LL and CL, in each n = 15). The rabbits were sacrificed at 1, 2 and 8 weeks postoperative, and formalin-fixed specimens were embedded in acrylic resin. The specimens were stained with hematoxylin and eosin. For immunohistochemical analysis, the specimens were treated with bone morphogenetic protein (BMP)-2 antibody. Group H had significantly higher values than groups L, E, and C regarding bone area ratio and labeling index of BMP-2 positive cells (P < 0.05). Furthermore, Group HL also had significantly higher values than the other groups regarding bone area ratio and labeling index of BMP-2 positive cells at 1, 2 and 8 weeks postoperative (P < 0.05). The results suggested that high density pore titanium mesh could induce new bone regeneration more than low density pore titanium mesh and ePTFE membrane. New bone formation may increase following LIPUS application. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  13. Expression of bone morphogenetic proteins 4, 6 and 7 is downregulated in kidney allografts with interstitial fibrosis and tubular atrophy.

    PubMed

    Furic-Cunko, Vesna; Kes, Petar; Coric, Marijana; Hudolin, Tvrtko; Kastelan, Zeljko; Basic-Jukic, Nikolina

    2015-07-01

    Bone morphogenetic proteins (BMPs) are pleiotropic growth factors. This paper investigates the connection between the expression pattern of BMPs in kidney allograft tissue versus the cause of allograft dysfunction. The expression pattern of BMP2, BMP4, BMP6 and BMP7 in 50 kidney allografts obtained by transplant nephrectomy is investigated. Immunohistochemical staining is semiquantitatively evaluated for intensity to identify the expression pattern of BMPs in normal and allograft kidney tissues. The expression of BMP4 is unique between different tubular cell types in grafts without signs of fibrosis. This effect is not found in specimens with high grades of interstitial fibrosis and tubular atrophy (IFTA). In samples with IFTA grades II and III, the BMP7 expression is reduced in a significant fraction of specimens relative to those without signs of IFTA. The expression pattern of BMP6 indicates that its activation may be triggered by the act of transplantation and subsequent reperfusion injury. The expression of BMP2 is strong in all types of tubular epithelial cells and does not differ between the compared allografts and control kidney specimens. The intensity and expression pattern of BMP4, BMP6 and BMP7 in transplanted kidney tissue are found to be dependent upon the length of the transplanted period, the clinical indication for transplant nephrectomy and signs of IFTA in kidney tissue.

  14. Bone morphogenetic protein 9 regulates tumor growth of osteosarcoma cells through the Wnt/β-catenin pathway.

    PubMed

    Lv, Zilan; Wang, Chuan; Yuan, Taixian; Liu, Yuehong; Song, Tao; Liu, Yueliang; Chen, Chu; Yang, Min; Tang, Zuchuan; Shi, Qiong; Weng, Yaguang

    2014-02-01

    Bone morphogenetic protein 9 (BMP9) is a member of the transforming growth factor-β (TGF-β) family, which has been shown to regulate the progression of several tumors. Recent studies indicated that BMP9 affects osteosarcoma (OS) processes, but its specific roles and molecular mechanisms have yet to be fully elucidated. The human OS cell lines 143B and MG63 were used for the present study. We found that BMP9 overexpression suppressed the growth of OS cells, whereas inhibition of BMP9 reversed this effect. Our results also showed that BMP9 overexpression induced G0/G1 phase arrest and apoptosis in OS cells. We further investigated the possible molecular mechanisms mediating the biological role of BMP9. We observed that BMP9 overexpression reduced β-catenin mRNA and protein levels, and also downregulated its downstream proteins c-Myc and osteoprotegerin (OPG) and inhibited the phosphorylation levels of GSK-3β (Ser 9) in OS cells, whereas inhibition of BMP9 reversed these effects. Moreover, the suppressive effects of BMP9 overexpression on OS cells was reversed by exogenous β-catenin expression, but augmented by β-catenin silencing. In conclusion, our results revealed that BMP9 can regulate tumor growth of OS cells through the Wnt/β-catenin pathway. Therefore, BMP9 may be a new therapeutic target in OS.

  15. Differential ubiquitination of Smad1 mediated by CHIP: implications in the regulation of the bone morphogenetic protein signaling pathway.

    PubMed

    Li, Ren-Feng; Shang, Yu; Liu, Di; Ren, Ze-Song; Chang, Zhijie; Sui, Sen-Fang

    2007-11-30

    Smad1, a downstream regulator of the bone morphogenetic protein (BMP) receptors, is tightly regulated by the ubiquitin-proteasomal degradation system. To dissect the mechanisms that underlie the regulation of Smad1, it is important to investigate the specific ubiquitination site(s) in Smad1. Here we report that the alpha-NH(2) group of the N terminus and the epsilon-NH(2) groups of internal lysine residues 116, 118 and 269 (K116, K118 and K269) of Smad1 are ubiquitin acceptor sites mediated by the carboxyl terminus of Hsc70-interacting protein (CHIP). The in vitro degradation assay indicates that ubiquitination at the N terminus partially contributes to the degradation of Smad1. Furthermore, we demonstrate that the ubiquitination level of pseudo-phosphorylated Smad1 by CHIP is stronger than that of wild-type Smad1 and can be strongly inhibited by a phosphorylated tail of Smad1, PIS(pS)V(pS). Third, our results indicate that Hsp70 facilitates CHIP-mediated poly-ubiquitination of Smad1 whereas it attenuates CHIP-meditated mono-ubiquitination of Smad1. Finally, consistent with the in vitro observation, we show that CHIP preferentially mediates the degradation of phospho-Smad1/5 in vivo. Taken together, these results provide us a hint that CHIP might preferentially regulate phosphorylated Smad1 and thus the BMP signaling.

  16. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression.

    PubMed

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-05-05

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2(f/f);Bmp4(f/f)ameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling.

  17. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression

    PubMed Central

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H.; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-01-01

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2f/f;Bmp4f/fameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling. PMID:27146352

  18. SoxB1-driven transcriptional network underlies neural-specific interpretation of morphogen signals.

    PubMed

    Oosterveen, Tony; Kurdija, Sanja; Ensterö, Mats; Uhde, Christopher W; Bergsland, Maria; Sandberg, Magnus; Sandberg, Rickard; Muhr, Jonas; Ericson, Johan

    2013-04-30

    The reiterative deployment of a small cadre of morphogen signals underlies patterning and growth of most tissues during embyogenesis, but how such inductive events result in tissue-specific responses remains poorly understood. By characterizing cis-regulatory modules (CRMs) associated with genes regulated by Sonic hedgehog (Shh), retinoids, or bone morphogenetic proteins in the CNS, we provide evidence that the neural-specific interpretation of morphogen signaling reflects a direct integration of these pathways with SoxB1 proteins at the CRM level. Moreover, expression of SoxB1 proteins in the limb bud confers on mesodermal cells the potential to activate neural-specific target genes upon Shh, retinoid, or bone morphogenetic protein signaling, and the collocation of binding sites for SoxB1 and morphogen-mediatory transcription factors in CRMs faithfully predicts neural-specific gene activity. Thus, an unexpectedly simple transcriptional paradigm appears to conceptually explain the neural-specific interpretation of pleiotropic signaling during vertebrate development. Importantly, genes induced in a SoxB1-dependent manner appear to constitute repressive gene regulatory networks that are directly interlinked at the CRM level to constrain the regional expression of patterning genes. Accordingly, not only does the topology of SoxB1-driven gene regulatory networks provide a tissue-specific mode of gene activation, but it also determines the spatial expression pattern of target genes within the developing neural tube.

  19. Defined culture medium for stem cell differentiation: applicability of serum-free conditions in the mouse embryonic stem cell test.

    PubMed

    Riebeling, Christian; Schlechter, Katharina; Buesen, Roland; Spielmann, Horst; Luch, Andreas; Seiler, Andrea

    2011-06-01

    The embryonic stem cell test (EST) is a validated method to assess the developmental toxicity potency of chemicals. It was developed to reduce animal use and allow faster testing for hazard assessment. The cells used in this method are maintained and differentiated in media containing foetal calf serum. This animal product is of considerable variation in quality, and individual batches require extensive testing for their applicability in the EST. Moreover, its production involves a large number of foetuses and possible animal suffering. We demonstrate the serum-free medium and feeder cell-free maintenance of the mouse embryonic stem cell line D3 and investigate the use of specific growth factors for induction of cardiac differentiation. Using a combination of bone morphogenetic protein-2, bone morphogenetic protein-4, activin A and ascorbic acid, embryoid bodies efficiently differentiated into contracting myocardium. Additionally, examining levels of intracellular marker proteins by flow cytometry not only confirmed differentiation into cardiomyocytes, but demonstrated significant differentiation into neuronal cells in the same time frame. Thus, this approach might allow for simultaneous detection of developmental effects on both early mesodermal and neuroectodermal differentiation. The serum-free conditions for maintenance and differentiation of D3 cells described here enhance the transferability and standardisation and hence the performance of the EST. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Inactivation of bone morphogenetic protein 2 may predict clinical outcome and poor overall survival for renal cell carcinoma through epigenetic pathways

    PubMed Central

    Mitsui, Yozo; Hirata, Hiroshi; Arichi, Naoko; Hiraki, Miho; Yasumoto, Hiroaki; Chang, Inik; Fukuhara, Shinichiro; Yamamura, Soichiro; Shahryari, Varahram; Deng, Guoren; Saini, Sharanjot; Majid, Shahana; Dahiya, Rajvir; Tanaka, Yuichiro; Shiina, Hiroaki

    2015-01-01

    We investigated whether impaired regulation of bone morphogenetic protein-2 (BMP-2) via epigenetic pathways is associated with renal cell carcinoma (RCC) pathogenesis. Expression and CpG methylation of the BMP-2 gene were analyzed using RCC cell lines, and 96 matched RCC and normal renal tissues. We also performed functional analysis using BMP-2 restored RCC cells. A significant association of BMP-2 mRNA expression was also found with advanced tumor stage and lymph node involvement, while lower BMP-2 mRNA expression was significantly associated with poor overall survival after radical nephrectomy. In RCC cells, BMP-2 restoration significantly inhibited cell proliferation, migration, invasion, and colony formation. In addition, BMP-2 overexpression induced p21WAF1/CIP1 and p27KIP1 expression, and cellular apoptosis in RCC cells. BMP-2 mRNA expression was significantly enhanced in RCC cells by 5-aza-2′-deoxycitidine treatment. The prevalence of BMP-2 promoter methylation was significantly greater and BMP-2 mRNA expression was significantly lower in RCC samples as compared to normal kidney samples. Furthermore, a significant correlation was found between BMP-2 promoter methylation and mRNA transcription in tumors. Aberrant BMP-2 methylation and the resultant loss of BMP-2 expression may be a useful molecular marker for designing improved diagnostic and therapeutic strategies for RCC. PMID:25797254

  1. Response Of Mineralizing And Non-Mineralizing Bone Cells To Fluid Flow: An In Vitro Model For Mechanotransruction

    NASA Technical Reports Server (NTRS)

    Makuch, Lauren A.

    2004-01-01

    Humans reach peak bone mass at age 30. After this point, we lose 1 to 2 percent of bone mass each decade. In the microgravity environment of space, astronauts lose bone mass at an accelerated rate of 1 to 2 percent each month. When astronauts travel to Mars, they may be in space for as long as 3 years. During this time, they may lose about half of their bone mass from weight-bearing bones. This loss may be irreversible. The drastic loss in bone that astronauts experience in space makes them much more vulnerable to fractures. In addition, the corresponding removal of calcium from bone results in higher levels of calcium in the blood, which increases the risk of developing kidney stones. Currently, studies are being conducted which investigate factors governing bone adaptation and mechanotransduction. Bone is constantly adapting in response to mechanical stimuli. Increased mechanical loading stimulates bone formation and suppresses bone resorption. Reduction in mechanical loading caused by bedrest, disuse, or microgravity results in decreased bone formation and possibly increased bone resorption. Osteoblasts and osteoclasts are the two main cell types that participate in bone remodeling. Osteoblasts are anabolic (bone-forming) cells and osteoclasts are catabolic (bone-resorbing) cells. In microgravity, the activity of osteoblasts slows down and the activity of osteoclasts may speed up, causing a loss of bone density. Mechanotransduction, the molecular mechanism by which mechanical stimuli are converted to biochemical signals, is not yet understood. Exposure of cells to fluid flow imposes a shear stress on the cells. Several studies have shown that the shear stress that results from fluid flow induces a cellular response similar to that induced by mechanical loading. Thus, fluid flow can be used as an in vitro model to simulate the mechanical stress that bone cells experience in vivo. Previous in vitro studies have shown that fluid flow induces several responses in osteoblasts, including increased proliferation, osteoblastic differentiation, alkaline phosphatase activity, and production of nitric oxide, prostaglandins, and osteopontin. Several proteins have been implicated in osteoblastic mechanotransduction including Bone Morphogenetic Protein-2 (BMP-2), parathyroid hormone, 1,25-dihydroxyvitamin D3 receptor, osteopontin (OPN), osteoprotegerin (OPG), and alkaline phosphatase (AP). We will characterize relative levels of each protein in mineralizing or non-mineralizing MC3T3 osteoblastic cells that have been exposed to fluid flow compared to non-fluid flow using immunofluorescent staining and two- photon laser microscopy as well as western blotting. Because calcium-mediated pathways are important in osteoblastic signaling, we will transfect MC3T3 cells with cameleon probes for Ca2+ containing YFP and CFP. Results will be analyzed using FRET/FLIM to study differential release of intracellular Ca(2+) in response to fluid flow and conditions inducing matrix mineralization. In addition, we plan to conduct several microarray experiments to determine differential gene expression in MC3T3 cells in response to fluid flow and conditions inducing mineralization.

  2. Healing of a Large Long-Bone Defect through Serum-Free In Vitro Priming of Human Periosteum-Derived Cells.

    PubMed

    Bolander, Johanna; Ji, Wei; Leijten, Jeroen; Teixeira, Liliana Moreira; Bloemen, Veerle; Lambrechts, Dennis; Chaklader, Malay; Luyten, Frank P

    2017-03-14

    Clinical translation of cell-based strategies for regenerative medicine demands predictable in vivo performance where the use of sera during in vitro preparation inherently limits the efficacy and reproducibility. Here, we present a bioinspired approach by serum-free pre-conditioning of human periosteum-derived cells, followed by their assembly into microaggregates simultaneously primed with bone morphogenetic protein 2 (BMP-2). Pre-conditioning resulted in a more potent progenitor cell population, while aggregation induced osteochondrogenic differentiation, further enhanced by BMP-2 stimulation. Ectopic implantation displayed a cascade of events that closely resembled the natural endochondral process resulting in bone ossicle formation. Assessment in a critical size long-bone defect in immunodeficient mice demonstrated successful bridging of the defect within 4 weeks, with active contribution of the implanted cells. In short, the presented serum-free process represents a biomimetic strategy, resulting in a cartilage tissue intermediate that, upon implantation, robustly leads to the healing of a large long-bone defect. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  3. High-density human mesenchymal stem cell rings with spatiotemporally-controlled morphogen presentation as building blocks for engineering bone diaphyseal tissue

    PubMed Central

    Herberg, Samuel; Varghai, Daniel; Cheng, Yuxuan; Dikina, Anna D.; Dang, Phuong N.; Rolle, Marsha W.; Alsberg, Eben

    2018-01-01

    Emerging biomimetic tissue engineering strategies aim to partially recapitulate fundamental events that transpire during embryonic skeletal development; namely, cellular self-organization and targeted morphogenetic pathway activation. Here, we describe self-assembled, scaffold-free human mesenchymal stem cell (hMSC) rings featuring microparticle-mediated presentation of transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2). We tested the hypothesis that spatiotemporally-controlled dual presentation of TGF-β1 and BMP-2 is superior in modulating in vitro endochondral ossification of high-density cellular constructs compared to single morphogen delivery. hMSC rings were engineered by seeding cells with microparticles presenting (1) TGF-β1, (2) BMP-2, or (3) TGF-β1 + BMP-2 in custom agarose wells to facilitate self-assembly within 2 d, followed by horizontal culture on glass tubes for 5 weeks. At day 2, hMSC rings across groups revealed homogenous cellular organization mimetic of early mesenchymal condensation with no evidence of new matrix or mineral deposition. Significant early chondrogenic and osteogenic priming occurred with TGF-β1 + BMP-2 presentation compared to single morphogen-loaded groups. By week 5, TGF-β1-loaded hMSC rings had undergone chondrogenesis, while presentation of BMP-2 alone or in conjunction with TGF-β1 stimulated chondrogenesis, chondrocyte hypertrophy, and osteogenesis indicative of endochondral ossification. Importantly, tissue mineralization was most compelling with TGF-β1 + BMP-2 loading. Lastly, hMSC ring 'building blocks' were shown to efficiently fuse into tubes within 6 d post self-assembly. The resulting tubular tissue units exhibited structural integrity, highlighting the translational potential of this advanced biomimetic technology for potential early implantation in long bone defects. PMID:29577017

  4. Continuous release of bone morphogenetic protein-2 through nano-graphene oxide-based delivery influences the activation of the NF-κB signal transduction pathway

    PubMed Central

    Zhong, Cheng; Feng, Jun; Lin, Xiangjin; Bao, Qi

    2017-01-01

    Graphene oxide (GO) has been used as a delivery vehicle for small molecule drugs and nucleotides. To further investigate GO as a smart biomaterial for the controlled release of cargo molecules, we hypothesized that GO may be an appropriate delivery vehicle because it releases bone morphogenetic protein 2 (BMP2). GO characterization indicated that the size distribution of the GO flakes ranged from 81.1 nm to 45,749.7 nm, with an approximate thickness of 2 nm. After BMP2 adsorption onto GO, Fourier-transformed infrared spectroscopy (FTIR) and thermal gravimetric analysis were performed. Compared to GO, BMP2-GO did not induce significant changes in the characteristics of the materials. GO continuously released BMP2 for at least 40 days. Bone marrow stem cells (BMSCs) and chondrocytes were treated with BMP2-GO in interleukin-1 media and assessed in terms of cell viability, flow cytometric characterization, and expression of particular mRNA. Compared to GO, BMP2-GO did not induce any significant changes in biocompatibility. We treated osteoarthritic rats with BMP2 and BMP2-GO, which showed significant differences in Osteoarthritis Research Society International (OARSI) scores (P<0.05). Quantitative assessment revealed significant differences compared to that using BMP2 and BMP2-GO (P<0.05). These findings indicate that GO may be potentially used to control the release of carrier materials. The combination of BMP2 and GO slowed the progression of NF-κB-activated degenerative changes in osteoarthritis. Therefore, we infer that our BMP2-GO strategy could alleviate the NF-κB pathway by inducing continuous BMP2 release. PMID:28243085

  5. Transient upregulation of CBFA1 in response to bone morphogenetic protein-2 and transforming growth factor beta1 in C2C12 myogenic cells coincides with suppression of the myogenic phenotype but is not sufficient for osteoblast differentiation.

    PubMed

    Lee, M H; Javed, A; Kim, H J; Shin, H I; Gutierrez, S; Choi, J Y; Rosen, V; Stein, J L; van Wijnen, A J; Stein, G S; Lian, J B; Ryoo, H M

    1999-04-01

    The bone morphogenetic protein (BMP)-2 is a potent osteoinductive signal, inducing bone formation in vivo and osteoblast differentiation from non-osseous cells in vitro. The runt domain-related protein Cbfa1/PEBP2alphaA/AML-3 is a critical component of bone formation in vivo and transcriptional regulator of osteoblast differentiation. To investigate the relationship between the extracellular BMP-2 signal, Cbfa1, and osteogenesis, we examined expression of Cbfa1 and osteoblastic genes during the BMP-2 induced osteogenic transdifferentiation of the myoblastic cell line C2C12. BMP-2 treatment completely blocked myotube formation and transiently induced expression of Cbfa1 and the bone-related homeodomain protein Msx-2 concomitant with loss of the myoblast phenotype. While induction of collagen type I and alkaline phosphatase (AP) expression coincided with Cbfa1 expression, Cbfa1 mRNA was strikingly downregulated at the onset of expression of osteopontin (OPN) and osteocalcin (OCN) genes, reflecting the mature osteoblast phenotype. TGF-beta1 treatment effectively suppressed myogenesis and induced Cbfa1 expression but was insufficient to support osteoblast differentiation reflected by the absence of ALP, OPN, and OCN. We addressed whether induction of Cbfa1 in response to BMP-2 results in the transcriptional activation of the OC promoter which contains three enhancer Cbfa1 elements. Transfection studies show BMP-2 suppresses OC promoter activity in C2C12, but not in osteoblastic ROS 17/2.8 cells. Maximal suppression of OC promoter activity in response to BMP-2 requires sequences in the proximal promoter (up to nt -365) and may occur independent of the three Cbfa sites. Taken together, our results demonstrate a dissociation of Cbfa1 expression from development of the osteoblast phenotype. Our findings suggest that Cbfal may function transiently to divert a committed myoblast to a potentially osteogenic cell. However, other factors induced by BMP-2 appear to be necessary for complete expression of the osteoblast phenotype.

  6. BMP2 repression and optimized culture conditions promote human bone marrow-derived mesenchymal stem cell isolation.

    PubMed

    Kay, Alasdair Gawain; Dale, Tina Patricia; Akram, Khondoker Mehedi; Mohan, Param; Hampson, Karen; Maffulli, Nicola; Spiteri, Monica A; El Haj, Alicia Jennifer; Forsyth, Nicholas Robert

    2015-01-01

    Human mesenchymal stem cells (hMSC) are multipotent progenitor cells. We propose the optimization of hMSC isolation and recovery using the application of a controlled hypoxic environment. We evaluated oxygen, glucose and serum in the recovery of hMSC from bone marrow (BMhMSC). Colony forming units-fibroblastic, cell numbers, tri-lineage differentiation, immunofluorescence and microarray were used to confirm and characterize BMhMSC. In an optimized (2% O(2), 4.5 g/l glucose and 5% serum) environment both colony forming units-fibroblastic (p = 0.01) and cell numbers (p = 0.0001) were enhanced over standard conditions. Transcriptional analysis identified differential expression of bone morphogenetic protein 2 (BMP2) and, putatively, chemokine (C-X-C motif) receptor 2 (CXCR2) signaling pathways. We have detailed a potential milestone in the process of refinement of the BMhMSC isolation process.

  7. Fracture healing: mechanisms and interventions

    PubMed Central

    Einhorn, Thomas A.; Gerstenfeld, Louis C.

    2015-01-01

    Fractures are the most common large-organ, traumatic injuries to humans. The repair of bone fractures is a postnatal regenerative process that recapitulates many of the ontological events of embryonic skeletal development. Although fracture repair usually restores the damaged skeletal organ to its pre-injury cellular composition, structure and biomechanical function, about 10% of fractures will not heal normally. This article reviews the developmental progression of fracture healing at the tissue, cellular and molecular levels. Innate and adaptive immune processes are discussed as a component of the injury response, as are environmental factors, such as the extent of injury to the bone and surrounding tissue, fixation and the contribution of vascular tissues. We also present strategies for fracture treatment that have been tested in animal models and in clinical trials or case series. The biophysical and biological basis of the molecular actions of various therapeutic approaches, including recombinant human bone morphogenetic proteins and parathyroid hormone therapy, are also discussed. PMID:25266456

  8. Bisphosphonate-decorated lipid nanoparticles designed as drug carriers for bone diseases.

    PubMed

    Wang, Guilin; Mostafa, Nesrine Z; Incani, Vanessa; Kucharski, Cezary; Uludağ, Hasan

    2012-03-01

    A conjugate of distearoylphosphoethanolamine-polyethylene glycol with 2-(3-mercaptopropylsulfanyl)-ethyl-1,1-bisphosphonic acid (thiolBP) was synthesized and incorporated into micelles and liposomes to create mineral-binding nanocarriers for therapeutic agents. The micelles and liposomes were used to encapsulate the anticancer drug doxorubicin (DOX) and a model protein lysozyme (LYZ) by using lipid film hydration (LFH) and reverse-phase evaporation vesicle (REV) methods. The results indicated that the micelles and LFH-derived liposomes were better at DOX loading than the REV-derived liposomes, while the REV method was preferable for encapsulating LYZ. The affinity of the micellar and liposomal formulations to hydroxyapatite (HA) was assessed in vitro, and the results indicated that all the thiolBP-incorporated nanocarriers had stronger HA affinity than their counterparts without thiolBP. The thiolBP-decorated liposomes also displayed a strong binding to a collagen/HA composite scaffold in vitro. More importantly, thiolBP-decorated liposomes gave increased retention in the collagen/HA scaffolds after subcutaneously implantation in rats. The designed liposomes were able to entrap the bone morphogenetic protein-2 in a bioactive form, indicating that the proposed nanocarriers could deliver bioactive factors locally in mineralized scaffolds for bone tissue engineering. Copyright © 2011 Wiley Periodicals, Inc.

  9. Investigation of gene expressions in differentiated cell derived bone marrow stem cells during bone morphogenetic protein-4 treatments with Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Zafari, Jaber; Jouni, Fatemeh Javani; Ahmadvand, Ali; Abdolmaleki, Parviz; Soodi, Malihe; Zendehdel, Rezvan

    2017-02-01

    A model was set up to predict the differentiation patterns based on the data extracted from FTIR spectroscopy. For this reason, bone marrow stem cells (BMSCs) were differentiated to primordial germ cells (PGCs). Changes in cellular macromolecules in the time of 0, 24, 48, 72, and 96 h of differentiation, as different steps of the differentiation procedure were investigated by using FTIR spectroscopy. Also, the expression of pluripotency (Oct-4, Nanog and c-Myc) and specific genes (Mvh, Stella and Fragilis) were investigated by real-time PCR. However, the expression of genes in five steps of differentiation was predicted by FTIR spectroscopy. FTIR spectra showed changes in the template of band intensities at different differentiation steps. There are increasing changes in the stepwise differentiation procedure for the ratio area of CH2, which is symmetric to CH2 asymmetric stretching. An ensemble of expert methods, including regression tree (RT), boosting algorithm (BA), and generalized regression neural network (GRNN), was the best method to predict the gene expression by FTIR spectroscopy. In conclusion, the model was able to distinguish the pattern of different steps from cell differentiation by using some useful features extracted from FTIR spectra.

  10. The Molecular and Cellular Events That Take Place during Craniofacial Distraction Osteogenesis

    PubMed Central

    Rachmiel, Adi

    2014-01-01

    Summary: Gradual bone lengthening using distraction osteogenesis principles is the gold standard for the treatment of hypoplastic facial bones. However, the long treatment time is a major disadvantage of the lengthening procedures. The aim of this study is to review the current literature and summarize the cellular and molecular events occurring during membranous craniofacial distraction osteogenesis. Mechanical stimulation by distraction induces biological responses of skeletal regeneration that is accomplished by a cascade of biological processes that may include differentiation of pluripotential tissue, angiogenesis, osteogenesis, mineralization, and remodeling. There are complex interactions between bone-forming osteoblasts and other cells present within the bone microenvironment, particularly vascular endothelial cells that may be pivotal members of a complex interactive communication network in bone. Studies have implicated number of cytokines that are intimately involved in the regulation of bone synthesis and turnover. The gene regulation of numerous cytokines (transforming growth factor-β, bone morphogenetic proteins, insulin-like growth factor-1, and fibroblast growth factor-2) and extracellular matrix proteins (osteonectin, osteopontin) during distraction osteogenesis has been best characterized and discussed. Understanding the biomolecular mechanisms that mediate membranous distraction osteogenesis may guide the development of targeted strategies designed to improve distraction osteogenesis and accelerate bone regeneration that may lead to shorten the treatment duration. PMID:25289295

  11. Hydroxyapatite paste Ostim, without elevation of full-thickness flaps, improves alveolar healing stimulating BMP- and VEGF-mediated signal pathways: an experimental study in humans.

    PubMed

    Canuto, R A; Pol, R; Martinasso, G; Muzio, G; Gallesio, G; Mozzati, M

    2013-08-01

    Tooth extraction is considered as the starting point of jaw atrophy via osteoclast activity stimulation. The maintenance of dental alveolar bone depends on surgery procedure and use of materials to maintain prior space favoring bone regeneration. Among substitutes used in dentistry to fill bone defects, Ostim-Pastes (Ostim) is a nanocrystalline paste tested for treatment of severe clinical conditions. This research first investigated the effect of Ostim on alveolar healing, comparing in the same healthy subjects, an Ostim-filled socket with a not-filled one. Moreover, it also proposed a new surgical protocol for the post-extractive socket treatment using the graft materials without elevation of full-thickness flaps. Fourteen patients were enrolled to bilateral maxillary or mandibular extraction that was performed without elevation of full-thickness flaps. In each patient, one socket was filled using Ostim, and the other one was allowed to undergo natural healing. No suture was carried out. Clinical and biologic parameters were screened at 1, 7, and 14 days. Obtained results evidenced that nanocrystalline hydroxyapatite supports bone regeneration, increasing the synthesis of pro-osteogenic factors as bone morphogenetics protein (BMP)-4, BMP-7, alkaline phosphatase, and osteocalcin. Moreover, filling post-extractive socket with nanocrystalline hydroxyapatite paste leads to a complete epithelialization already at 7 days after extraction, despite the fact that the teeth were extracted without elevation of full-thickness flaps . The improved epithelialization is mediated by increased vascular endothelial growth factor (VEGF) expression. No significant change was observed in inflammatory parameters, with exception of an early and transient IL-1β induction, that could trigger and improve alveolar healing. Clinical and biomolecular observations of this explorative study evidenced that nanocrystalline hydroxyapatite improves alveolar socket healing, increasing angiogenesis, epithelialization, and osteogenesis, also in absence of elevation of full-thickness flaps. © 2011 John Wiley & Sons A/S.

  12. Effect of boron on osteogenic differentiation of human bone marrow stromal cells.

    PubMed

    Ying, Xiaozhou; Cheng, Shaowen; Wang, Wei; Lin, Zhongqin; Chen, Qingyu; Zhang, Wei; Kou, Dongquan; Shen, Yue; Cheng, Xiaojie; Rompis, Ferdinand An; Peng, Lei; Zhu Lu, Chuan

    2011-12-01

    Bone marrow stromal cells (BMSCs) have been well established as an ideal source of cell-based therapy for bone tissue engineering applications. Boron (B) is a notable trace element in humans; so far, the effects of boron on the osteogenic differentiation of BMSCs have not been reported. The aim of this study was to evaluate the effects of boron (0, 1, 10,100, and 1,000 ng/ml) on osteogenic differentiation of human BMSCs. In this study, BMSCs proliferation was analyzed by cell counting kit-8 (CCK8) assay, and cell osteogenic differentiation was evaluated by alkaline phosphatase (ALP) activity assay, Von Kossa staining, and real-time PCR. The results indicated that the proliferation of BMSCs was no different from the control group when added with B at the concentration of 1, 10, and 100 ng/ml respectively (P > 0.05); in contrast, 1,000 ng/ml B inhibited the proliferation of BMSCs at days 4, 7, and 14 (P < 0.05). By ALP staining, we discovered that BMSCs treated with 10 and 100 ng/ml B presented a higher ALP activity compared with control (P < 0.05). By real-time PCR, we detected the messenger RNA expression of ALP, osteocalcin, collagen type I, and bone morphogenetic proteins 7 were also increased in 10 and 100 ng/ml B treatment groups (P < 0.05). The calcium depositions were increased in 1 and 10 ng/ml B treatment groups (P < 0.05). Taken all together, it was the first time to report that B could increase osteogenic effect by stimulating osteogenic differentiation-related marker gene synthesis during the proliferation and differentiation phase in human BMSCs and could be a promising approach for enhancing osteogenic capacity of cell-based construction in bone tissue engineering.

  13. Combined Use of Mesenchymal Stromal Cell Sheet Transplantation and Local Injection of SDF-1 for Bone Repair in a Rat Nonunion Model.

    PubMed

    Chen, Guangnan; Fang, Tingting; Qi, Yiying; Yin, Xiaofan; Di, Tuoyu; Feng, Gang; Lei, Zhong; Zhang, Yuxiang; Huang, Zhongming

    2016-10-01

    Bone nonunion treatments pose a challenge in orthopedics. This study investigated the joint effects of using mesenchymal stem cell (MSC) sheets with local injection of stromal cell-derived factor-1 (SDF-1) on bone formation. In vitro, we found that migration of MSCs was mediated by SDF-1 in a dose-dependent manner. Moreover, stimulation with SDF-1 had no direct effect on the proliferation or osteogenic differentiation of MSCs. Furthermore, the results indicated elevated expression levels of bone morphogenetic protein 2, alkaline phosphatase, osteocalcin, and vascular endothelial growth factor in MSC sheets compared with MSCs cultured in medium. New bone formation in fractures was evaluated by X-ray, micro-computed tomography (micro-CT), hematoxylin and eosin (H&E) staining, Safranin-O staining, and immunohistochemistry in vivo. In the rat bone fracture model, the MSC sheets transplanted into the injured site along with injection of SDF-1 showed significantly more new bone formation within the gap. Moreover, at 8 weeks, complete bone union was obtained in this group. In contrast, the control group showed nonunion of the bone. Our study suggests a new strategy involving the use of MSC sheets with a local injection of SDF-1 for hard tissue reconstruction, such as the healing of nonunions and bone defects.

  14. Endothelial Notch activity promotes angiogenesis and osteogenesis in bone

    NASA Astrophysics Data System (ADS)

    Ramasamy, Saravana K.; Kusumbe, Anjali P.; Wang, Lin; Adams, Ralf H.

    2014-03-01

    Blood vessel growth in the skeletal system and osteogenesis seem to be coupled, suggesting the existence of molecular crosstalk between endothelial and osteoblastic cells. Understanding the nature of the mechanisms linking angiogenesis and bone formation should be of great relevance for improved fracture healing or prevention of bone mass loss. Here we show that vascular growth in bone involves a specialized, tissue-specific form of angiogenesis. Notch signalling promotes endothelial cell proliferation and vessel growth in postnatal long bone, which is the opposite of the well-established function of Notch and its ligand Dll4 in the endothelium of other organs and tumours. Endothelial-cell-specific and inducible genetic disruption of Notch signalling in mice not only impaired bone vessel morphology and growth, but also led to reduced osteogenesis, shortening of long bones, chondrocyte defects, loss of trabeculae and decreased bone mass. On the basis of a series of genetic experiments, we conclude that skeletal defects in these mutants involved defective angiocrine release of Noggin from endothelial cells, which is positively regulated by Notch. Administration of recombinant Noggin, a secreted antagonist of bone morphogenetic proteins, restored bone growth and mineralization, chondrocyte maturation, the formation of trabeculae and osteoprogenitor numbers in endothelial-cell-specific Notch pathway mutants. These findings establish a molecular framework coupling angiogenesis, angiocrine signals and osteogenesis, which may prove significant for the development of future therapeutic applications.

  15. Repair of segmental bone defects with bone marrow and BMP-2 adenovirus in the rabbit radius

    NASA Astrophysics Data System (ADS)

    Cheng, Lijia; Lu, Xiaofeng; Shi, Yujun; Li, Li; Xue, Jing; Zhang, Li; Xia, Jie; Wang, Yujia; Zhang, Xingdong; Bu, Hong

    2012-12-01

    Bone tissue engineering (BTE) is approached via implantation of autogenous mesenchymal stem cells (MSCs), marrow cells, or platelet-rich plasma, etc. To the contrary, gene therapy combining with the bone marrow (BM) has not been often reported. This study was performed to investigate whether a modified BTE method, that is, the BM and a recombinant human bone morphogenetic protein-2 adenovirus (Ad.hBMP-2) gene administering in hydroxyapatite/β-tricalcium phosphate (HA/β-TCP) ceramics could accelerate the healing of segmental defects in the rabbit radius. In our study, ceramics were immersed in the adenovirus overnight, and half an hour before surgery, autologous BM aspirates were thoroughly mixed with the ceramics; at the same time, a 15-mm radius defect was introduced in the bilateral forelimbs of all animals, after that, this defect was filled with the following: (1) Ad.hBMP-2 + HA/β-TCP + autologous BM (group 1); (2) HA/β-TCP + Ad.hBMP-2 (group 2); (3) HA/β-TCP alone (group 3); (4) an empty defect as a control (group 4). Histological observation and μ-CT analyses were performed on the specimens at weeks 2, 4, 8, and 12, respectively. In group 1, new bone was observed at week 4 and BM appeared at week 12, in groups 2 and 3, new bone was observed at week 8 and it was more mature at week 12, in contrast, the defect was not bridged in group 4 at week 12. The new bone area percentage in group 1 was significantly higher than that in groups 2 and 3. Our study indicated that BM combined with hBMP-2 adenovirus and porous ceramics could significantly increase the amount of newly formed bone. And this modified BTE method thus might have potentials in future clinical application.

  16. Sodium hyaluronate accelerates the healing process in tooth sockets of rats.

    PubMed

    Mendes, Renato M; Silva, Gerluza A B; Lima, Miguel F; Calliari, Marcelo V; Almeida, Alvair P; Alves, José B; Ferreira, Anderson J

    2008-12-01

    In this study we evaluated the effects of sodium hyaluronate (HY) in the healing process of tooth sockets of rats. Immediately after the extraction of the upper first molars of male Holtzman rats, right sockets were treated with 1% HY gel (approximately 0.1 ml), while left sockets were used as control (blood clot). The animals were sacrificed at 2, 7, and 21 days after tooth extraction and upper maxillaries processed for histological and morphometric analysis of the apical and medium thirds of the sockets. Carbopol, an inert gel, was used to evaluate the mechanical effect of gel injection into sockets. Expression of bone morphogenetic protein-2 (BMP-2) and osteopontin (OPN) was determined by immunohistochemistry at 1, 2, 3, 4, 5, and 7 days after tooth extraction. Histological analysis showed that HY treatment induced earlier trabecular bone deposition resulting in a bone matrix more organized at 7 and 21 days after tooth extraction. Also, HY elicited significant increase in the amount of bone trabeculaes at 7 and 21 days after tooth extraction (percentage of trabecular bone area at 7 days: 13.21+/-4.66% vs. 2.58+/-1.36% in the apical third of control sockets) and in the vessels counting at 7 days. Conversely, the number of cell nuclei was decreased in HY-treated sockets. Additionally, expression of BMP-2 and OPN was enhanced in HY-treated sockets compared with control sockets. These findings suggest that HY accelerates the healing process in tooth sockets of rats stimulating the expression of osteogenic proteins.

  17. Alginate/Gelatin scaffolds incorporated with Silibinin-loaded Chitosan nanoparticles for bone formation in vitro.

    PubMed

    Leena, R S; Vairamani, M; Selvamurugan, N

    2017-10-01

    Silibinin is a plant derived flavonolignan known for its multiple biological properties, but its role in the promotion of bone formation has not yet been well studied. Moreover, the delivery of Silibinin is hindered by its complex hydrophobic nature, which limits its bioavailability. Hence, in this study, we fabricated a drug delivery system using chitosan nanoparticles loaded with Silibinin at different concentrations (20μM, 50μM, and 100μM). They were then incorporated into scaffolds containing Alginate and Gelatin (Alg/Gel) for the sustained and prolonged release of Silibinin. The Silibinin-loaded chitosan nanoparticles (SCN) were prepared using the ionic gelation technique, and the scaffolds (Alg/Gel-SCN) were synthesized by the conventional method of freeze drying. The scaffolds were subjected to physicochemical and material characterization studies. The addition of SCN did not affect the porosity of the scaffolds, yet increased the protein adsorption, degradation rates, and bio-mineralization. These scaffolds were biocompatible with mouse mesenchymal stem cells. The scaffolds loaded with 50μM Silibinin promoted osteoblast differentiation, which was determined at cellular and molecular levels. Recent studies indicated the role of microRNAs (miRNAs) in osteogenesis and we found that the Silibinin released from scaffolds regulated miRNAs that control the bone morphogenetic protein pathway. Hence, our results suggest the potential for sustained and prolonged release of Silibinin to promote bone formation and, thus, these Alg/Gel-SCN scaffolds may be candidates for bone tissue engineering applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. FGF2 High Molecular Weight Isoforms Contribute to Osteoarthropathy in Male Mice

    PubMed Central

    Meo Burt, Patience; Xiao, Liping; Dealy, Caroline; Fisher, Melanie C.

    2016-01-01

    Humans with X-linked hypophosphatemia (XLH) and Hyp mice, the murine homolog of the disease, develop severe osteoarthropathy and the precise factors that contribute to this joint degeneration remain largely unknown. Fibroblast growth factor 2 (FGF2) is a key regulatory growth factor in osteoarthritis. Although there are multiple FGF2 isoforms the potential involvement of specific FGF2 isoforms in joint degradation has not been investigated. Mice that overexpress the high molecular weight FGF2 isoforms in bone (HMWTg mice) phenocopy Hyp mice and XLH subjects and Hyp mice overexpress the HMWFGF2 isoforms in osteoblasts and osteocytes. Given that Hyp mice and XLH subjects develop osteoarthropathies we examined whether HMWTg mice also develop knee joint degeneration at 2, 8, and 18 mo compared with VectorTg (control) mice. HMWTg mice developed spontaneous osteoarthropathy as early as age 2 mo with thinning of subchondral bone, osteophyte formation, decreased articular cartilage thickness, abnormal mineralization within the joint, increased cartilage degradative enzymes, hypertrophic markers, and angiogenesis. FGF receptors 1 and 3 and fibroblast growth factor 23 were significantly altered compared with VectorTg mice. In addition, gene expression of growth factors and cytokines including bone morphogenetic proteins, Insulin like growth factor 1, Interleukin 1 beta, as well as transcription factors Sex determining region Y box 9, hypoxia inducible factor 1, and nuclear factor kappa B subunit 1 were differentially modulated in HMWTg compared with VectorTg. This study demonstrates that overexpression of the HMW isoforms of FGF2 in bone results in catabolic activity in joint cartilage and bone that leads to osteoarthropathy. PMID:27732085

  19. Design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite as a potential bone graft substitute material

    NASA Astrophysics Data System (ADS)

    Florschutz, Anthony Vatroslav

    Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were implanted ectopically in a rodent animal model and histologically evaluated for biocompatibility, degradation, and bone formation in vivo. The gelatin-hydroxyapatite scaffolds retained dimensional structure over 28 days and did not elicit any undesirable systemic or local effects. Distinct areas of mineralization and osteoid/bone were noted in all the implanted scaffolds and quantitative differences were primarily dependent on the presence of hydroxyapatite.

  20. Comparative Analysis of Mouse-Induced Pluripotent Stem Cells and Mesenchymal Stem Cells During Osteogenic Differentiation In Vitro

    PubMed Central

    Kayashima, Hiroki; Miura, Jiro; Uraguchi, Shinya; Wang, Fangfang; Okawa, Hiroko; Sasaki, Jun-Ichi; Saeki, Makio; Matsumoto, Takuya; Yatani, Hirofumi

    2014-01-01

    Induced pluripotent stem cells (iPSCs) can differentiate into mineralizing cells and are, therefore, expected to be useful for bone regenerative medicine; however, the characteristics of iPSC-derived osteogenic cells remain unclear. Here, we provide a direct in vitro comparison of the osteogenic differentiation process in mesenchymal stem cells (MSCs) and iPSCs from adult C57BL/6J mice. After 30 days of culture in osteogenic medium, both MSCs and iPSCs produced robustly mineralized bone nodules that contained abundant calcium phosphate with hydroxyapatite crystal formation. Mineral deposition was significantly higher in iPSC cultures than in MSC cultures. Scanning electron microscopy revealed budding matrix vesicles in early osteogenic iPSCs; subsequently, the vesicles propagated to exhibit robust mineralization without rich fibrous structures. Early osteogenic MSCs showed deposition of many matrix vesicles in abundant collagen fibrils that became solid mineralized structures. Both cell types demonstrated increased expression of osteogenic marker genes, such as runx2, osterix, dlx5, bone sialoprotein (BSP), and osteocalcin, during osteogenesis; however, real-time reverse transcription–polymerase chain reaction array analysis revealed that osteogenesis-related genes encoding mineralization-associated molecules, bone morphogenetic proteins, and extracellular matrix collagens were differentially expressed between iPSCs and MSCs. These data suggest that iPSCs are capable of differentiation into mature osteoblasts whose associated hydroxyapatite has a crystal structure similar to that of MSC-associated hydroxyapatite; however, the transcriptional differences between iPSCs and MSCs could result in differences in the mineral and matrix environments of the bone nodules. Determining the biological mechanisms underlying cell-specific differences in mineralization during in vitro iPSC osteogenesis may facilitate the development of clinically effective engineered bone. PMID:24625139

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