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Sample records for bone morphogenic proteins

  1. Positive modulator of bone morphogenic protein-2

    DOEpatents

    Zamora, Paul O.; Pena, Louis A.; Lin, Xinhua; Takahashi, Kazuyuki

    2009-01-27

    Compounds of the present invention of formula I and formula II are disclosed in the specification and wherein the compounds are modulators of Bone Morphogenic Protein activity. Compounds are synthetic peptides having a non-growth factor heparin binding region, a linker, and sequences that bind specifically to a receptor for Bone Morphogenic Protein. Uses of compounds of the present invention in the treatment of bone lesions, degenerative joint disease and to enhance bone formation are disclosed.

  2. Positive modulator of bone morphogenic protein-2

    DOEpatents

    Zamora, Paul O.; Pena, Louis A.; Lin, Xinhua; Kazuyuki, Takahashi

    2017-06-06

    Compounds of the present invention of formula I and formula II are disclosed in the specification and wherein the compounds are modulators of Bone Morphogenic Protein activity. Compounds are synthetic peptides having a non-growth factor heparin binding region, a linker, and sequences that bind specifically to a receptor for Bone Morphogenic Protein. Uses of compounds of the present invention in the treatment of bone lesions, degenerative joint disease and to enhance bone formation are disclosed.

  3. Effects of Bone Morphogenic Proteins on Engineered Cartilage

    NASA Technical Reports Server (NTRS)

    Gooch, Keith, J.; Blunk, Torsten; Courter, Donald L.; Sieminski, Alisha; Vunjak-Novakovic, Gordana; Freed, Lisa E.

    2007-01-01

    A report describes experiments on the effects of bone morphogenic proteins (BMPs) on engineered cartilage grown in vitro. In the experiments, bovine calf articular chondrocytes were seeded onto biodegradable polyglycolic acid scaffolds and cultured in, variously, a control medium or a medium supplemented with BMP-2, BMP-12, or BMP-13 in various concentrations. Under all conditions investigated, cell-polymer constructs cultivated for 4 weeks macroscopically and histologically resembled native cartilage. At a concentration of 100 ng/mL, BMP-2, BMP-12, or BMP-13 caused (1) total masses of the constructs to exceed those of the controls by 121, 80, or 62 percent, respectively; (2) weight percentages of glycosaminoglycans in the constructs to increase by 27, 18, or 15, respectively; and (3) total collagen contents of the constructs to decrease to 63, 89, or 83 percent of the control values, respectively. BMP-2, but not BMP-12 or BMP-13, promoted chondrocyte hypertrophy. These observations were interpreted as suggesting that the three BMPs increase the growth rates and modulate the compositions of engineered cartilage. It was also concluded that in vitro engineered cartilage is a suitable system for studying effects of BMPs on chondrogenesis in a well-defined environment.

  4. Evaluation of bone morphogenic proteins in periodontal practice

    PubMed Central

    Kaur, Supreet; Grover, Vishakha; Kaur, Harkiran; Malhotra, Ranjan

    2016-01-01

    Forty years ago Marshal R. Urist discovered a substance in bone matrix that had inductive properties for the development of bone and cartilage, until date, at least 20 bone morphogenetic proteins (BMPs) have been identified, some of which have been shown in vitro to stimulate the process of stem cell differentiation into osteoblasts in human and animal models. The purpose of this paper is to give a brief overview of BMPs and to review critically the clinical data currently available on the use of BMPs in various periodontal applications. The literature on BMPs was reviewed. A comprehensive search was designed. The articles were independently screened for eligibility. Articles with authentic controls and proper randomization and pertaining specifically to their role in periodontal applications were included. The available literature was analyzed and compiled. The analysis indicates BMPs to be a promising, as well as an effective novel approach to reconstruct and engineer the periodontal apparatus. Here, we represent several articles, as well as recent texts that make up a special and an in-depth review on the subject. On the basis of the data provided in the studies that were reviewed BMPs provide revolutionary therapies in periodontal practice. PMID:27134452

  5. Takotsubo Cardiomyopathy following a L2–L5 Laminectomy and Fusion In Situ with Bone Morphogenic Protein

    PubMed Central

    Eubanks, Jason

    2013-01-01

    Takotsubo cardiomyopathy (TC) is a rare, transient cardiomyopathy, with symptoms mimicking myocardial infarction. It has been reported to typically occur in postmenopausal women and is often triggered by an intense physical or emotional event with stimulation of the sympathetic response; the exact etiology, however, is uncertain. Bone morphogenic protein (BMP) is widely used in spinal fusions and has been associated with numerous perioperative complications. BMP is known to stimulate sympathetic pathways. In this paper, we present the case of a patient with a 7-hour episode of TC after a spinal fusion with bone morphogenic protein. The patient's symptoms resolved and long-term followup has been uneventful. This is the first paper to describe TC in the setting of spine or other major orthopaedic surgery and it suggests another possible area for further investigation in peri-operative events potentially associated with the use of bone morphogenic protein. PMID:23585979

  6. The "bone morphogenic proteins" pathways in bone and joint diseases: translational perspectives from physiopathology to therapeutic targets.

    PubMed

    Biver, Emmanuel; Hardouin, Pierre; Caverzasio, Joseph

    2013-02-01

    A large body of evidence supports an important role of bone morphogenic proteins (BMPs) pathways in skeletal development in the embryo. BMPs are also involved in skeletal homeostasis and diseases in the adult. They were first identified as major bone anabolic agents and recent advances indicate that they also regulate osteoclastogenesis and joint components via multiple cross-talks with other signaling pathways. This review attempts to integrate these data in the pathogenesis of bone and joints diseases, such as osteoporosis, fracture healing, osteoarthritis, inflammatory arthritis, or bone metastasis. The use of recombinant BMPs in bone tissue engineering and in the treatment of skeletal diseases, or future therapeutic strategies targeting BMPs signal and its regulators, will be discussed based on these considerations.

  7. A Biphasic Calcium Sulphate/Hydroxyapatite Carrier Containing Bone Morphogenic Protein-2 and Zoledronic Acid Generates Bone.

    PubMed

    Raina, Deepak Bushan; Isaksson, Hanna; Hettwer, Werner; Kumar, Ashok; Lidgren, Lars; Tägil, Magnus

    2016-05-18

    In orthopedic surgery, large amount of diseased or injured bone routinely needs to be replaced. Autografts are mainly used but their availability is limited. Commercially available bone substitutes allow bone ingrowth but lack the capacity to induce bone formation. Thus, off-the-shelf osteoinductive bone substitutes that can replace bone grafts are required. We tested the carrier properties of a biphasic, calcium sulphate and hydroxyapatite ceramic material, containing a combination of recombinant human bone morphogenic protein-2 (rhBMP-2) to induce bone, and zoledronic acid (ZA) to delay early resorption. In-vitro, the biphasic material released 90% of rhBMP-2 and 10% of ZA in the first week. No major changes were found in the surface structure using scanning electron microscopy (SEM) or in the mechanical properties after adding rhBMP-2 or ZA. In-vivo bone formation was studied in an abdominal muscle pouch model in rats (n = 6/group). The mineralized volume was significantly higher when the biphasic material was combined with both rhBMP-2 and ZA (21.4 ± 5.5 mm(3)) as compared to rhBMP-2 alone (10.9 ± 2.1 mm(3)) when analyzed using micro computed tomography (μ-CT) (p < 0.01). In the clinical setting, the biphasic material combined with both rhBMP-2 and ZA can potentially regenerate large volumes of bone.

  8. Bone morphogenic protein 4 produced in endothelial cells by oscillatory shear stress stimulates an inflammatory response

    NASA Technical Reports Server (NTRS)

    Sorescu, George P.; Sykes, Michelle; Weiss, Daiana; Platt, Manu O.; Saha, Aniket; Hwang, Jinah; Boyd, Nolan; Boo, Yong C.; Vega, J. David; Taylor, W. Robert; hide

    2003-01-01

    Atherosclerosis is now viewed as an inflammatory disease occurring preferentially in arterial regions exposed to disturbed flow conditions, including oscillatory shear stress (OS), in branched arteries. In contrast, the arterial regions exposed to laminar shear (LS) are relatively lesion-free. The mechanisms underlying the opposite effects of OS and LS on the inflammatory and atherogenic processes are not clearly understood. Here, through DNA microarrays, protein expression, and functional studies, we identify bone morphogenic protein 4 (BMP4) as a mechanosensitive and pro-inflammatory gene product. Exposing endothelial cells to OS increased BMP4 protein expression, whereas LS decreased it. In addition, we found BMP4 expression only in the selective patches of endothelial cells overlying foam cell lesions in human coronary arteries. The same endothelial patches also expressed higher levels of intercellular cell adhesion molecule-1 (ICAM-1) protein compared with those of non-diseased areas. Functionally, we show that OS and BMP4 induced ICAM-1 expression and monocyte adhesion by a NFkappaB-dependent mechanism. We suggest that BMP4 is a mechanosensitive, inflammatory factor playing a critical role in early steps of atherogenesis in the lesion-prone areas.

  9. Bone morphogenic protein 4 produced in endothelial cells by oscillatory shear stress stimulates an inflammatory response

    NASA Technical Reports Server (NTRS)

    Sorescu, George P.; Sykes, Michelle; Weiss, Daiana; Platt, Manu O.; Saha, Aniket; Hwang, Jinah; Boyd, Nolan; Boo, Yong C.; Vega, J. David; Taylor, W. Robert; Jo, Hanjoong

    2003-01-01

    Atherosclerosis is now viewed as an inflammatory disease occurring preferentially in arterial regions exposed to disturbed flow conditions, including oscillatory shear stress (OS), in branched arteries. In contrast, the arterial regions exposed to laminar shear (LS) are relatively lesion-free. The mechanisms underlying the opposite effects of OS and LS on the inflammatory and atherogenic processes are not clearly understood. Here, through DNA microarrays, protein expression, and functional studies, we identify bone morphogenic protein 4 (BMP4) as a mechanosensitive and pro-inflammatory gene product. Exposing endothelial cells to OS increased BMP4 protein expression, whereas LS decreased it. In addition, we found BMP4 expression only in the selective patches of endothelial cells overlying foam cell lesions in human coronary arteries. The same endothelial patches also expressed higher levels of intercellular cell adhesion molecule-1 (ICAM-1) protein compared with those of non-diseased areas. Functionally, we show that OS and BMP4 induced ICAM-1 expression and monocyte adhesion by a NFkappaB-dependent mechanism. We suggest that BMP4 is a mechanosensitive, inflammatory factor playing a critical role in early steps of atherogenesis in the lesion-prone areas.

  10. Public awareness of the bone morphogenic protein controversy: Evidence from news publications

    PubMed Central

    Drazin, Doniel; Shweikeh, Faris; Wieshofer, Erich; Kim, Terrence T.; Johnson, J. Patrick

    2014-01-01

    Background: Use of recombinant human bone morphogenic protein-2 (rhBMP-2) in spinal fusion has seen a tremendous increase. Public awareness of rhBMP-2 and its complications has not been assessed. The authors studied published news media articles to analyze information provided to the public on this bone graft substitute. Methods: We utilized the academic database, LexisNexis, to locate newspaper articles published between January 2001 and July 2013. All articles were coded by a coder and reviewed by the principal investigator. Results: The search identified 87 national and 99 local newspaper articles. Complications mentioned in national newspapers included cancer (24%), retrograde ejaculation (24%), and abnormal bone growth (14%). Local newspapers cited cancer (14%), inflammation (14%), and retrograde ejaculation (9.2%) most frequently. Fifty national (59%) and 35 local (54%) articles had no mention of complications. Sources of evidence cited by articles were (in order of frequency): Governmental agencies, medical research or published studies, healthcare personnel or patients, and companies or corporations. Conclusions: Only a small percentage of newspaper articles presented potential complications. Despite lack of clear scientific causal relationship between rhBMP-2 and cancer, this risk was disproportionately reported. Additionally, many did not cite scientific sources. Lack of reliable information available to the public reiterates the role of physicians in discussing risks and benefits BMP use in spinal surgery, assuring that patients are making informed decisions. Future news media articles should present risks in an impartial and evidence-based manner. Collaboration between advocacy groups, medical institutions, and media outlets would be beneficial in achieving this goal. PMID:25593772

  11. Bone morphogenic protein signaling is a major determinant of dentate development

    PubMed Central

    Choe, Youngshik; Kozlova, Anastasiia; Graf, Daniel; Pleasure, Samuel J.

    2013-01-01

    To understand life-long neurogenesis in the dentate gyrus (DG), characterizing dentate neural stem cells and the signals controlling their development are crucial. In the present study, we show that bone morphogenic protein (Bmp) signaling is a critical regulator of embryonic dentate development, required for initiating neurogenesis in embryonic DG progenitors and required for the establishment of dentate neural stem cells postnatally. We tested the hypothesis that Bmp signaling regulates dentate development in part by controlling the expression of Lef1, a Wnt responsive transcription factor expressed in dentate stem cells and absolutely required for dentate granule cell production. Bmp activation through the Acvr1 receptor induced Lef1 expression and neurogenesis in the embryonic DG. Ectopic expression of Bmp7 in the embryonic midline increased DG neurogenesis and inhibition of local Bmp signaling decreased embryonic DG neurogenesis. Mice with selective loss of Bmp expression due to defective meningeal development or with selective conditional deletion of meningeal Bmp7 also have dentate developmental defects. Conditional deletion of Acvr1 or Smad4 (a downstream target nuclear effector of Bmp signaling) in DG neural stem cells resulted in defects in the postnatal subgranular zone (SGZ) and reduced neurogenesis. These results suggest that Acvr1 mediated meningeal Bmp signaling regulates Lef1 expression in the dentate, regulating embryonic DG neurogenesis, DG neural stem cell niche formation and maintenance. PMID:23595735

  12. Bone morphogenic protein signaling is a major determinant of dentate development.

    PubMed

    Choe, Youngshik; Kozlova, Anastasiia; Graf, Daniel; Pleasure, Samuel J

    2013-04-17

    To understand life-long neurogenesis in the dentate gyrus (DG), characterizing dentate neural stem cells and the signals controlling their development are crucial. In the present study, we show that bone morphogenic protein (Bmp) signaling is a critical regulator of embryonic dentate development, required for initiating neurogenesis in embryonic DG progenitors and required for the establishment of dentate neural stem cells postnatally. We tested the hypothesis that Bmp signaling regulates dentate development in part by controlling the expression of Lef1, a Wnt responsive transcription factor expressed in dentate stem cells and absolutely required for dentate granule cell production. Bmp activation through the Acvr1 receptor induced Lef1 expression and neurogenesis in the embryonic DG. Ectopic expression of Bmp7 in the embryonic midline increased DG neurogenesis and inhibition of local Bmp signaling decreased embryonic DG neurogenesis. Mice with selective loss of Bmp expression due to defective meningeal development or with selective conditional deletion of meningeal Bmp7 also have dentate developmental defects. Conditional deletion of Activin receptor type I (Acvr1) or Smad4 (a downstream target nuclear effector of Bmp signaling) in DG neural stem cells resulted in defects in the postnatal subgranular zone and reduced neurogenesis. These results suggest that Acvr1-mediated meningeal Bmp signaling regulates Lef1 expression in the dentate, regulating embryonic DG neurogenesis, DG neural stem cell niche formation, and maintenance.

  13. Bone morphogenic protein signalling suppresses differentiation of pluripotent cells by maintaining expression of E-Cadherin.

    PubMed

    Malaguti, Mattias; Nistor, Paul A; Blin, Guillaume; Pegg, Amy; Zhou, Xinzhi; Lowell, Sally

    2013-12-17

    Bone morphogenic protein (BMP) signalling contributes towards maintenance of pluripotency and favours mesodermal over neural fates upon differentiation, but the mechanisms by which BMP controls differentiation are not well understood. We report that BMP regulates differentiation by blocking downregulation of Cdh1, an event that accompanies the earliest stages of neural and mesodermal differentiation. We find that loss of Cdh1 is a limiting requirement for differentiation of pluripotent cells, and that experimental suppression of Cdh1 activity rescues the BMP-imposed block to differentiation. We further show that BMP acts prior to and independently of Cdh1 to prime pluripotent cells for mesoderm differentiation, thus helping to reinforce the block to neural differentiation. We conclude that differentiation depends not only on exposure to appropriate extrinsic cues but also on morphogenetic events that control receptivity to those differentiation cues, and we explain how a key pluripotency signal, BMP, feeds into this control mechanism. DOI: http://dx.doi.org/10.7554/eLife.01197.001.

  14. Bone morphogenic protein signalling suppresses differentiation of pluripotent cells by maintaining expression of E-Cadherin

    PubMed Central

    Malaguti, Mattias; Nistor, Paul A; Blin, Guillaume; Pegg, Amy; Zhou, Xinzhi; Lowell, Sally

    2013-01-01

    Bone morphogenic protein (BMP) signalling contributes towards maintenance of pluripotency and favours mesodermal over neural fates upon differentiation, but the mechanisms by which BMP controls differentiation are not well understood. We report that BMP regulates differentiation by blocking downregulation of Cdh1, an event that accompanies the earliest stages of neural and mesodermal differentiation. We find that loss of Cdh1 is a limiting requirement for differentiation of pluripotent cells, and that experimental suppression of Cdh1 activity rescues the BMP-imposed block to differentiation. We further show that BMP acts prior to and independently of Cdh1 to prime pluripotent cells for mesoderm differentiation, thus helping to reinforce the block to neural differentiation. We conclude that differentiation depends not only on exposure to appropriate extrinsic cues but also on morphogenetic events that control receptivity to those differentiation cues, and we explain how a key pluripotency signal, BMP, feeds into this control mechanism. DOI: http://dx.doi.org/10.7554/eLife.01197.001 PMID:24347544

  15. Transforming Growth Factor β Can Stimulate Smad1 Phosphorylation Independently of Bone Morphogenic Protein Receptors*

    PubMed Central

    Wrighton, Katharine H.; Lin, Xia; Yu, Paul B.; Feng, Xin-Hua

    2009-01-01

    Transforming growth factor-β (TGFβ) superfamily ligands control a diverse set of cellular processes by activating type I and type II serine-threonine receptor kinases. Canonical TGFβ signaling is mediated via the TβRI/ALK5 type I receptor that phosphorylates Smad2 and Smad3 in their SXS motif to facilitate their activation and subsequent role in transcriptional regulation. Canonical bone morphogenic protein (BMP) signaling is mediated via the ALK1/2/3/6 type I receptors that phosphorylate Smad1, Smad5, and Smad8 in their SXS motif. However, studies in endothelial cells have shown that TGFβ can also lead to the phosphorylation of Smad1, dependent on ALK1 receptor activity. Here we present data showing that TGFβ can significantly induce Smad1 phosphorylation in several non-endothelial cell lineages. Additionally, by using chemical inhibitors specific for the TGFβ/activin/nodal (ALK4/5/7) and BMP (ALK1/2/3/6) type I receptors, we show that in some cell types TGFβ induces Smad1 phosphorylation independently of the BMP type I receptors. Thus, TGFβ-mediated Smad1 phosphorylation appears to occur via different receptor complexes in a cell type-specific manner. PMID:19224917

  16. Transforming Growth Factor {beta} Can Stimulate Smad1 Phosphorylation Independently of Bone Morphogenic Protein Receptors.

    PubMed

    Wrighton, Katharine H; Lin, Xia; Yu, Paul B; Feng, Xin-Hua

    2009-04-10

    Transforming growth factor-beta (TGFbeta) superfamily ligands control a diverse set of cellular processes by activating type I and type II serine-threonine receptor kinases. Canonical TGFbeta signaling is mediated via the TbetaRI/ALK5 type I receptor that phosphorylates Smad2 and Smad3 in their SXS motif to facilitate their activation and subsequent role in transcriptional regulation. Canonical bone morphogenic protein (BMP) signaling is mediated via the ALK1/2/3/6 type I receptors that phosphorylate Smad1, Smad5, and Smad8 in their SXS motif. However, studies in endothelial cells have shown that TGFbeta can also lead to the phosphorylation of Smad1, dependent on ALK1 receptor activity. Here we present data showing that TGFbeta can significantly induce Smad1 phosphorylation in several non-endothelial cell lineages. Additionally, by using chemical inhibitors specific for the TGFbeta/activin/nodal (ALK4/5/7) and BMP (ALK1/2/3/6) type I receptors, we show that in some cell types TGFbeta induces Smad1 phosphorylation independently of the BMP type I receptors. Thus, TGFbeta-mediated Smad1 phosphorylation appears to occur via different receptor complexes in a cell type-specific manner.

  17. A Biphasic Calcium Sulphate/Hydroxyapatite Carrier Containing Bone Morphogenic Protein-2 and Zoledronic Acid Generates Bone

    PubMed Central

    Raina, Deepak Bushan; Isaksson, Hanna; Hettwer, Werner; Kumar, Ashok; Lidgren, Lars; Tägil, Magnus

    2016-01-01

    In orthopedic surgery, large amount of diseased or injured bone routinely needs to be replaced. Autografts are mainly used but their availability is limited. Commercially available bone substitutes allow bone ingrowth but lack the capacity to induce bone formation. Thus, off-the-shelf osteoinductive bone substitutes that can replace bone grafts are required. We tested the carrier properties of a biphasic, calcium sulphate and hydroxyapatite ceramic material, containing a combination of recombinant human bone morphogenic protein-2 (rhBMP-2) to induce bone, and zoledronic acid (ZA) to delay early resorption. In-vitro, the biphasic material released 90% of rhBMP-2 and 10% of ZA in the first week. No major changes were found in the surface structure using scanning electron microscopy (SEM) or in the mechanical properties after adding rhBMP-2 or ZA. In-vivo bone formation was studied in an abdominal muscle pouch model in rats (n = 6/group). The mineralized volume was significantly higher when the biphasic material was combined with both rhBMP-2 and ZA (21.4 ± 5.5 mm3) as compared to rhBMP-2 alone (10.9 ± 2.1 mm3) when analyzed using micro computed tomography (μ-CT) (p < 0.01). In the clinical setting, the biphasic material combined with both rhBMP-2 and ZA can potentially regenerate large volumes of bone. PMID:27189411

  18. Rapid Activation of Bone Morphogenic Protein 9 by Receptor-mediated Displacement of Pro-domains*

    PubMed Central

    Kienast, Yvonne; Jucknischke, Ute; Scheiblich, Stefan; Thier, Martina; de Wouters, Mariana; Haas, Alexander; Lehmann, Christian; Brand, Verena; Bernicke, Dirk; Honold, Konrad; Lorenz, Stefan

    2016-01-01

    By non-covalent association after proteolytic cleavage, the pro-domains modulate the activities of the mature growth factor domains across the transforming growth factor-β family. In the case of bone morphogenic protein 9 (BMP9), however, the pro-domains do not inhibit the bioactivity of the growth factor, and the BMP9·pro-domain complexes have equivalent biological activities as the BMP9 mature ligand dimers. By using real-time surface plasmon resonance, we could demonstrate that either binding of pro-domain-complexed BMP9 to type I receptor activin receptor-like kinase 1 (ALK1), type II receptors, co-receptor endoglin, or to mature BMP9 domain targeting antibodies leads to immediate and complete displacement of the pro-domains from the complex. Vice versa, pro-domain binding by an anti-pro-domain antibody results in release of the mature BMP9 growth factor. Based on these findings, we adjusted ELISA assays to measure the protein levels of different BMP9 variants. Although mature BMP9 and inactive precursor BMP9 protein were directly detectable by ELISA, BMP9·pro-domain complex could only be measured indirectly as dissociated fragments due to displacement of mature growth factor and pro-domains after antibody binding. Our studies provide a model in which BMP9 can be readily activated upon getting into contact with its receptors. This increases the understanding of the underlying biology of BMP9 activation and also provides guidance for ELISA development for the detection of circulating BMP9 variants. PMID:26677222

  19. Rapid Activation of Bone Morphogenic Protein 9 by Receptor-mediated Displacement of Pro-domains.

    PubMed

    Kienast, Yvonne; Jucknischke, Ute; Scheiblich, Stefan; Thier, Martina; de Wouters, Mariana; Haas, Alexander; Lehmann, Christian; Brand, Verena; Bernicke, Dirk; Honold, Konrad; Lorenz, Stefan

    2016-02-12

    By non-covalent association after proteolytic cleavage, the pro-domains modulate the activities of the mature growth factor domains across the transforming growth factor-β family. In the case of bone morphogenic protein 9 (BMP9), however, the pro-domains do not inhibit the bioactivity of the growth factor, and the BMP9·pro-domain complexes have equivalent biological activities as the BMP9 mature ligand dimers. By using real-time surface plasmon resonance, we could demonstrate that either binding of pro-domain-complexed BMP9 to type I receptor activin receptor-like kinase 1 (ALK1), type II receptors, co-receptor endoglin, or to mature BMP9 domain targeting antibodies leads to immediate and complete displacement of the pro-domains from the complex. Vice versa, pro-domain binding by an anti-pro-domain antibody results in release of the mature BMP9 growth factor. Based on these findings, we adjusted ELISA assays to measure the protein levels of different BMP9 variants. Although mature BMP9 and inactive precursor BMP9 protein were directly detectable by ELISA, BMP9·pro-domain complex could only be measured indirectly as dissociated fragments due to displacement of mature growth factor and pro-domains after antibody binding. Our studies provide a model in which BMP9 can be readily activated upon getting into contact with its receptors. This increases the understanding of the underlying biology of BMP9 activation and also provides guidance for ELISA development for the detection of circulating BMP9 variants. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. 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.

  1. Bone Morphogenic Protein Is a Viable Adjunct for Fusion in Minimally Invasive Transforaminal Lumbar Interbody Fusion

    PubMed Central

    Siddiqui, M Mashfiqul Arafin; Sta.Ana, Ana Rosario P.; Yeo, William

    2016-01-01

    Study Design Comparison of prospectively collected data of patients undergoing minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) with and without recombinant human bone morphogenic protein 2 (BMP). Purpose To compare the clinical, radiological outcome and complications of patients undergoing MIS-TLIF with and without BMP. Overview of Literature BMP is an effective fusion enhancer with potential complications. Direct comparison of MIS-TLIF with and without BMP is limited to retrospective studies with short follow-up. Methods From June 2005 to February 2011, consecutive cases of MIS-TLIF performed by a single surgeon were included. North American Spine Society (NASS) score, Oswestry disability index (ODI), Short Form-36 (SF-36), and visual analogue score (VAS) were assessed preoperatively and at 6 and 24 months postoperatively. Fusion rates and complications were noted. Results The 252 cases comprised 104 non-BMP and 148 BMP cases. The BMP group was significantly older (mean age, 60.2 vs. 53.9; p<0.01). Preoperative scores were similar. Immediate postoperative morphine usage was significantly lower in the BMP group (12.4 mg vs. 20.1 mg, p<0.01). At 6 months, the BMP group had lower VAS back and leg pain scores (p<0.01). At 2 years, the BMP group had better leg pain scores (p<0.01), ODI (15.4 vs. 20.3, p=0.04) and NASS scores (8.8 vs. 15.8, p<0.01). Both groups showed significant clinical improvement compared to their preoperative levels. The BMP group attained a significantly higher rate of fusion at 6 months follow-up (88.4% vs. 76.8%, p=0.016) with no difference at 2 years. The non-BMP and BMP group had 12 (11.5%) and 9 (6.1%) complications and 5 (4.8%) and 2 (1.4%) reoperations, respectively. Conclusions The use of BMP to augment fusion in MIS-TLIF is an acceptable alternative that has potential benefits of less pain in early and intermediate postoperative follow-up. PMID:27994786

  2. Infant formula promotes bone growth in neonatal piglets by enhancing osteoblastogenesis through bone morphogenic protein signaling

    USDA-ARS?s Scientific Manuscript database

    Relatively few studies have examined the effects of formula feeding relative to breast-feeding on bone in the neonate. Using peripheral quantitative CT scan and histomorphometric analysis, we demonstrated that neonatal piglets fed with soy-based formula (SF) and cow milk-based formula (MF) for 21 or...

  3. Plasma Surface Modification for Immobilization of Bone Morphogenic Protein-2 on Polycaprolactone Scaffolds

    NASA Astrophysics Data System (ADS)

    Kim, Byung Hoon; Myung, Sung Woon; Jung, Sang Chul; Ko, Yeong Mu

    2013-11-01

    The immobilization of recombinant human bone formation protein-2 (rhBMP-2) on polycaprolactone (PCL) scaffolds was performed by plasma polymerization. RhBMP-2, which induces osteoblast differentiation in various cell types, is a growth factor that plays an important role in bone formation and repair. The surface of the PCL scaffold was functionalized with the carboxyl groups of plasma-polymerized acrylic acid (PPAA) thin films. Plasma polymerization was carried out at a discharge power of 60 W at an acrylic acid flow rate of 7 sccm for 5 min. The PPAA thin film exhibited moderate hydrophilic properties and possessed a high density of carboxyl groups. Carboxyl groups and rhBMP-2 on the PCL scaffolds surface were identified by attenuated total reflection Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, respectively. The alkaline phosphatase activity assay showed that the rhBMP-2 immobilized PCL scaffold increased the level of MG-63 cell differentiation. Plasma surface modification for the preparation of biomaterials, such as biofunctionalized polymer scaffolds, can be used for the binding of bioactive molecules in tissue engineering.

  4. The role of hepatocyte hemojuvelin in the regulation of bone morphogenic protein-6 and hepcidin expression in vivo.

    PubMed

    Zhang, An-Sheng; Gao, Junwei; Koeberl, Dwight D; Enns, Caroline A

    2010-05-28

    Both hemojuvelin (HJV) and bone morphogenic protein-6 (BMP6) are essential for hepcidin expression. Hepcidin is the key peptide hormone in iron homeostasis, and is secreted predominantly by hepatocytes. HJV expression is detected in hepatocytes, as well as in skeletal and heart muscle. HJV binds BMP6 and increases hepcidin expression presumably by acting as a BMP co-receptor. We characterized the role of hepatocyte HJV in the regulation of BMP6 and hepcidin expression. In HJV-null (Hjv(-/-)) mice that have severe iron overload and marked suppression of hepcidin expression, we detected 4-fold higher hepatic BMP6 mRNA than in wild-type counterparts. These results indicate that Hjv(-/-) mice do not lack BMP6. Furthermore, iron depletion in Hjv(-/-) mice decreased hepatic BMP6 mRNA. Expression of HJV in hepatocytes of Hjv(-/-) mice using an AAV2/8 vector, increased hepatic hepcidin mRNA by 65-fold and phosphorylated Smad1/5/8 in the liver by about 2.5-fold. However, no significant change in BMP6 mRNA was detected in either the liver or the small intestine of these animals. Our results revealed a close correlation of hepatic BMP6 mRNA expression with hepatic iron-loading. Together, our data indicate that the regulation of hepatic BMP6 expression by iron is independent of HJV, and that expression of HJV in hepatocytes plays an essential role in hepcidin expression by potentiating the BMP6-mediated signaling.

  5. Gentamicin and bone morphogenic protein-2 (BMP-2)-delivering heparinized-titanium implant with enhanced antibacterial activity and osteointegration.

    PubMed

    Lee, Deok-Won; Yun, Young-Pil; Park, Kyeongsoon; Kim, Sung Eun

    2012-04-01

    Insufficient bonding of implants to bone tissues and bacterial infections lead to the failure of titanium (Ti)-based orthopedic and dental implants. The aim of this study is to develop novel Ti implants that enhance osteoblast functions, while simultaneously decreasing bacterial infections. First, the surface of pristine Ti was functionalized with heparin-dopamine by mimicking a mussel adhesion mechanism. Gentamicin sulfate (GS) and/or bone morphogenic protein-2 (BMP-2) was then sequentially immobilized to the heparinized-Ti (Hep-Ti) surface. The compositions of pristine Ti and Hep-Ti with or without gentamicin and/or BMP-2 were characterized by X-ray photoelectron spectroscopy (XPS) and the growth of Staphylococcus aureus on the substrates was assayed. Osteoblast functions of all Ti substrates were investigated by cell proliferation assays, alkaline phosphatase (ALP) activity, and calcium deposition. The results showed that the growth of bacteria on GS/Hep-Ti and GS/BMP-2/Hep-Ti was significantly lower compared to that on the pristine Ti and BMP-2/Hep-Ti. In addition, BMP-2/Hep-Ti and GS/BMP-2/Hep-Ti significantly enhanced ALP activity and calcium mineral deposition of osteoblast cells. Taken together, GS/BMP-2/Hep-Ti could achieve the dual functions of excellent antibacterial activity and osteoblast function promotion. Therefore, dual drug (antibiotics and osteoinductive protein)-eluting Ti substrates such as GS/BMP-2/Hep-Ti are a promising material for the enhanced osteointegration and implant longevity in orthopedics and dentistry. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Recombinant human bone morphogenic protein-2-enhanced anterior spine fusion without bone encroachment into the spinal canal: a histomorphometric study in a thoracoscopically instrumented porcine model.

    PubMed

    Zhang, Hong; Sucato, Daniel J; Welch, Robert D

    2005-03-01

    A thoracoscopically assisted 5-level anterior spinal fusion and instrumentation model analyzing new bone formation when using recombinant human bone morphogenic protein-2 (rhBMP-2) with a collagen hydroxyapatite-tricalcium phosphate (HA/TCP) composite sponge carrier. To determine whether new bone formation extends beyond the posterior confines of the vertebral body encroaching into the spinal canal when rhBMP-2 is used to enhance anterior fusion. A possible concern regarding the use of rhBMP-2 to enhance spinal fusion is the risk of unwanted bone formation leading to inadvertent fusion of adjacent levels or compression of neural elements. The safety of rhBMP-2 in one spinal application does not ensure similar results in other applications. Therefore, the expanded use of rhBMP-2 should occur only after carefully monitored preclinical and clinical studies for each new application. Eighteen pigs underwent thoracoscopically-assisted instrumentation and fusion of 5 contiguous levels (T5-T10) and randomly assigned to 4 treatment groups: group 1 (n = 6): rh-BMP-2 on a HA/TCP-collagen sponge (Medtronic Sofamor Danek, Memphis, TN); group 2 (n = 4): iliac crest autograft; group 3 (n = 4): empty; group 4 (n = 4): HA/TCP-collagen sponge (Medtronic Sofamor Danek) only. In groups 1 and 4, the HA/TCP collagen sponge was morselized into small granules and pushed through a bone delivery funnel for implantation into the disc. At 4 months after surgery, spines were sectioned longitudinally through the midsagittal plane and underwent undecalcified processing. Bone formation extending beyond the margins of the original discectomy and the confines of vertebral body were evaluated histomorphometrically at each operative level. Recombinant human bone morphogenic protein-2 on a HA/TCP-collagen sponge induced significant new bone formation extending anterior to the confines of the vertebral body compared with the other treatment groups (P < 0.05). In addition, rhBMP-2 on a HA

  7. Bone morphogenic protein-2 regulates the myogenic differentiation of PMVECs in CBDL rat serum-induced pulmonary microvascular remodeling.

    PubMed

    Liu, Chang; Chen, Lin; Zeng, Jing; Cui, Jian; Ning, Jiao-Nin; Wang, Guan-Song; Belguise, Karine; Wang, Xiaobo; Qian, Gui-Sheng; Lu, Kai-Zhi; Yi, Bin

    2015-08-01

    Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling.

  8. Bone Morphogenic Protein Type 2 Receptor Mutation-Independent Mechanisms of Disrupted Bone Morphogenetic Protein Signaling in Idiopathic Pulmonary Arterial Hypertension.

    PubMed

    Barnes, Jarrod W; Kucera, Elif T; Tian, Liping; Mellor, Noël E; Dvorina, Nina; Baldwin, William W; Aldred, Micheala A; Farver, Carol F; Comhair, Suzy A A; Aytekin, Metin; Dweik, Raed A

    2016-10-01

    Altered bone morphogenic protein (BMP) signaling, independent of BMPR2 mutations, can result in idiopathic pulmonary arterial hypertension (IPAH). Glucose dysregulation can regulate multiple processes in IPAH. However, the role of glucose in BMP antagonist expression in IPAH has not been characterized. We hypothesized that glucose uptake regulates BMP signaling through stimulation of BMP antagonist expression in IPAH. Using human plasma, lung tissue, and primary pulmonary arterial smooth muscle cells (PASMCs), we examined the protein expression of BMP2, BMP-regulated Smads, and Smurf-1 in patients with IPAH and control subjects. Gremlin-1 levels were elevated in patients with IPAH compared with control subjects, whereas expression of BMP2 was not different. We demonstrate increased Smad polyubiquitination in IPAH lung tissue and PASMCs that was further enhanced with proteasomal inhibition. Examination of the Smad ubiquitin-ligase, Smurf-1, showed increased protein expression in IPAH lung tissue and localization in the smooth muscle of the pulmonary artery. Glucose dose dependently increased Smurf-1 protein expression in control PASMCs, whereas Smurf-1 in IPAH PASMCs was increased and sustained. Conversely, phospho-Smad1/5/8 levels were reduced in IPAH compared with control PASMCs at physiological glucose concentrations. Interestingly, high glucose concentrations decreased phosphorylation of Smad1/5/8 in control PASMCs. Blocking glucose uptake had opposing effects in IPAH PASMCs, and inhibition of Smurf-1 activity resulted in partial rescue of Smad1/5/8 activation and cell migration rates. Collectively, these data suggest that BMP signaling can be regulated through BMPR2 mutation-independent mechanisms. Gremlin-1 (synonym: induced-in-high-glucose-2 protein) and Smurf-1 may function to inhibit BMP signaling as a consequence of the glucose dysregulation described in IPAH.

  9. The Role of Hepatocyte Hemojuvelin in the Regulation of Bone Morphogenic Protein-6 and Hepcidin Expression in Vivo*

    PubMed Central

    Zhang, An-Sheng; Gao, Junwei; Koeberl, Dwight D.; Enns, Caroline A.

    2010-01-01

    Both hemojuvelin (HJV) and bone morphogenic protein-6 (BMP6) are essential for hepcidin expression. Hepcidin is the key peptide hormone in iron homeostasis, and is secreted predominantly by hepatocytes. HJV expression is detected in hepatocytes, as well as in skeletal and heart muscle. HJV binds BMP6 and increases hepcidin expression presumably by acting as a BMP co-receptor. We characterized the role of hepatocyte HJV in the regulation of BMP6 and hepcidin expression. In HJV-null (Hjv−/−) mice that have severe iron overload and marked suppression of hepcidin expression, we detected 4-fold higher hepatic BMP6 mRNA than in wild-type counterparts. These results indicate that Hjv−/− mice do not lack BMP6. Furthermore, iron depletion in Hjv−/− mice decreased hepatic BMP6 mRNA. Expression of HJV in hepatocytes of Hjv−/− mice using an AAV2/8 vector, increased hepatic hepcidin mRNA by 65-fold and phosphorylated Smad1/5/8 in the liver by about 2.5-fold. However, no significant change in BMP6 mRNA was detected in either the liver or the small intestine of these animals. Our results revealed a close correlation of hepatic BMP6 mRNA expression with hepatic iron-loading. Together, our data indicate that the regulation of hepatic BMP6 expression by iron is independent of HJV, and that expression of HJV in hepatocytes plays an essential role in hepcidin expression by potentiating the BMP6-mediated signaling. PMID:20363739

  10. Bone morphogenic protein-2 regulates the myogenic differentiation of PMVECs in CBDL rat serum-induced pulmonary microvascular remodeling

    SciTech Connect

    Liu, Chang; Chen, Lin; Zeng, Jing; Cui, Jian; Ning, Jiao-nin; Wang, Guan-song; Belguise, Karine; Wang, Xiaobo; Qian, Gui-sheng; Lu, Kai-zhi; Yi, Bin

    2015-08-01

    Hepatopulmonary syndrome (HPS) is characterized by an arterial oxygenation defect induced by intrapulmonary vasodilation (IPVD) that increases morbidity and mortality. In our previous study, it was determined that both the proliferation and the myogenic differentiation of pulmonary microvascular endothelial cells (PMVECs) play a key role in the development of IPVD. However, the molecular mechanism underlying the relationship between IPVD and the myogenic differentiation of PMVECs remains unknown. Additionally, it has been shown that bone morphogenic protein-2 (BMP2), via the control of protein expression, may regulate cell differentiation including cardiomyocyte differentiation, neuronal differentiation and odontoblastic differentiation. In this study, we observed that common bile duct ligation (CBDL)-rat serum induced the upregulation of the expression of several myogenic proteins (SM-α-actin, calponin, SM-MHC) and enhanced the expression levels of BMP2 mRNA and protein in PMVECs. We also observed that both the expression levels of Smad1/5 and the activation of phosphorylated Smad1/5 were significantly elevated in PMVECs following exposure to CBDL-rat serum, which was accompanied by the down-regulation of Smurf1. The blockage of the BMP2/Smad signaling pathway with Noggin inhibited the myogenic differentiation of PMVECs, a process that was associated with relatively low expression levels of both SM-α-actin and calponin in the setting of CBDL-rat serum exposure, although SM-MHC expression was not affected. These findings suggested that the BMP2/Smad signaling pathway is involved in the myogenic differentiation of the PMVECs. In conclusion, our data highlight the pivotal role of BMP2 in the CBDL-rat serum-induced myogenic differentiation of PMVECs via the activation of both Smad1 and Smad5 and the down-regulation of Smurf1, which may represent a potential therapy for HPS-induced pulmonary vascular remodeling. - Highlights: • CBDL-rat serum promotes the myogenic

  11. Macrophage bone morphogenic protein receptor 2 depletion in idiopathic pulmonary fibrosis and Group III pulmonary hypertension.

    PubMed

    Chen, Ning-Yuan; D Collum, Scott; Luo, Fayong; Weng, Tingting; Le, Thuy-Trahn; M Hernandez, Adriana; Philip, Kemly; Molina, Jose G; Garcia-Morales, Luis J; Cao, Yanna; Ko, Tien C; Amione-Guerra, Javier; Al-Jabbari, Odeaa; Bunge, Raquel R; Youker, Keith; Bruckner, Brian A; Hamid, Rizwan; Davies, Jonathan; Sinha, Neeraj; Karmouty-Quintana, Harry

    2016-08-01

    Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology. The development of pulmonary hypertension (PH) is considered the single most significant predictor of mortality in patients with chronic lung diseases. The processes that govern the progression and development of fibroproliferative and vascular lesions in IPF are not fully understood. Using human lung explant samples from patients with IPF with or without a diagnosis of PH as well as normal control tissue, we report reduced BMPR2 expression in patients with IPF or IPF+PH. These changes were consistent with dampened P-SMAD 1/5/8 and elevated P-SMAD 2/3, demonstrating reduced BMPR2 signaling and elevated TGF-β activity in IPF. In the bleomycin (BLM) model of lung fibrosis and PH, we also report decreased BMPR2 expression compared with control animals that correlated with vascular remodeling and PH. We show that genetic abrogation or pharmacological inhibition of interleukin-6 leads to diminished markers of fibrosis and PH consistent with elevated levels of BMPR2 and reduced levels of a collection of microRNAs (miRs) that are able to degrade BMPR2. We also demonstrate that isolated bone marrow-derived macrophages from BLM-exposed mice show reduced BMPR2 levels upon exposure with IL6 or the IL6+IL6R complex that are consistent with immunohistochemistry showing reduced BMPR2 in CD206 expressing macrophages from lung sections from IPF and IPF+PH patients. In conclusion, our data suggest that depletion of BMPR2 mediated by a collection of miRs induced by IL6 and subsequent STAT3 phosphorylation as a novel mechanism participating to fibroproliferative and vascular injuries in IPF. Copyright © 2016 the American Physiological Society.

  12. KDM5A controls bone morphogenic protein 2-induced osteogenic differentiation of bone mesenchymal stem cells during osteoporosis

    PubMed Central

    Wang, Chuandong; Wang, Jing; Li, Jiao; Hu, Guoli; Shan, Shengzhou; Li, Qingfeng; Zhang, Xiaoling

    2016-01-01

    Bone morphogenetic protein 2 (BMP2) has been used to induce bone regeneration by promoting osteogenic differentiation of bone marrow-derived mesenchymal stem cells (MSCs). However, its effect is attenuated in osteoporotic conditions by unknown mechanisms. In this study, we investigated the molecular mechanisms of reduced osteogenic effect of BMP2 in osteoporotic conditions. By interrogating the microarray data from osteoporosis patients, we revealed an upregulation of the epigenetic modifying protein lysine (K)-specific demethylase 5A (KDM5A) and decreased Runt-related transcription factor 2 (RUNX2) expression. Further studies were focused on the role of KDM5A in osteoporosis. We first established ovariectomized (OVX) mouse model and found that the BMP2-induced osteogenic differentiation of osteoporotic MSCs was impaired. The elevated level of KDM5A was confirmed in osteoporotic MSCs. Overexpression of KDM5A in normal MSCs inhibited BMP2-induced osteogenesis. Moreover, osteogenic differentiation of osteoporotic MSCs was restored by specific KDM5A short hairpin RNA or inhibitor. Furthermore, by chromatin immunoprecipitation assay we demonstrated that KDM5A functions as endogenous modulator of osteogenic differentiation by decreasing H3K4me3 levels on promoters of Runx2, depend on its histone methylation activity. More importantly, we found an inhibitory role of KDM5A in regulating bone formation in osteoporotic mice, and pretreatment with KDM5A inhibitor partly rescued the bone loss during osteoporosis. Our results show, for the first time, that KDM5A-mediated H3K4me3 modification participated in the etiology of osteoporosis and may provide new strategies to improve the clinical efficacy of BMP2 in osteoporotic conditions. PMID:27512956

  13. Effects of exogenous recombinant human bone morphogenic protein-7 on the corneal epithelial mesenchymal transition and fibrosis

    PubMed Central

    Chung, Jin Kwon; Park, Shin Ae; Hwang, Hee Sun; Kim, Kwang Sung; Cho, Yang Je; You, Yong Sung; Kim, Young Sik; Jang, Ju Woong; Lee, Sung Jin

    2017-01-01

    AIM To evaluate the effect of exogenous recombinant human bone morphogenic protein-7 (rhBMP-7) on transforming growth factor-β (TGF-β)-induced epithelial mesenchymal cell transition (EMT) and assessed its antifibrotic effect via topical application. METHODS The cytotoxic effect of rhBMP-7 was evaluated and the EMT of human corneal epithelial cells (HECEs) was induced by TGF-β. HECEs were then cultured in the presence of rhBMP-7 and/or hyaluronic acid (HA). EMT markers, fibronectin, E-cadherin, α-smooth muscle actin (α-SMA), and matrix metaloproteinase-9 (MMP-9), were evaluated. The level of corneal fibrosis and the reepithelization rate were evaluated using a rabbit keratectomy model. Expression of α-SMA in keratocytes were quantified following treatment with different concentrations of rhBMP-7. RESULTS Treatment with rhBMP-7 attenuated TGF-β-induced EMT in HECEs. It significantly attenuated fibronectin secretion (31.6%; P<0.05), the α-SMA protein level (72.2%; P<0.01), and MMP-9 expression (23.6%, P<0.05) in HECEs compared with cells grown in the presence of TGF-β alone. E-cadherin expression was significantly enhanced (289.7%; P<0.01) in the presence of rhBMP-7. Topical application of rhBMP-7 combined with 0.1% HA significantly reduced the amount of α-SMA+ cells by 43.18% (P<0.05) at a concentration of 2.5 µg/mL and by 47.73% (P<0.05) at 25 µg/mL, compared with the control group, without disturbing corneal reepithelization. CONCLUSION rhBMP-7 attenuates TGF-β-induced EMT in vitro, and topical application of rhBMP-7 reduces keratocyte myodifferentiation during the early wound healing stages in vivo without hindering reepithelization. Topical rhBMP-7 application as biological eye drops seems to be feasible in diseases involving TGF-β-related corneal fibrosis with corneal reepithelization disorders.

  14. Oncogenic features of the bone morphogenic protein 7 (BMP7) in pheochromocytoma

    PubMed Central

    Leinhäuser, Ines; Richter, Andrea; Lee, Misu; Höfig, Ines; Anastasov, Nataša; Fend, Falko; Ercolino, Tonino; Mannelli, Massimo; Gimenez-Roqueplo, Anne-Paule; Robledo, Mercedes; de Krijger, Ronald; Beuschlein, Felix; Atkinson, Michael J.; Pellegata, Natalia S.

    2015-01-01

    BMP7 is a growth factor playing pro- or anti-oncogenic roles in cancer in a cell type-dependent manner. We previously reported that the BMP7 gene is overexpressed in pheochromocytomas (PCCs) developing in MENX-affected rats and human patients. Here, analyzing a large cohort of PCC patients, we found that 72% of cases showed elevated levels of the BMP7 protein. To elucidate the role of BMP7 in PCC, we modulated its levels in PCC cell lines (overexpression in PC12, knockdown in MPC and MTT cells) and conducted functional assays. Active BMP signaling promoted cell proliferation, migration, and invasion, and sustained survival of MENX rat primary PCC cells. In PCC, BMP7 signals through the PI3K/AKT/mTOR pathway and causes integrin β1 up-regulation. Silencing integrin β1 in PC12 cells suppressed BMP7-mediated oncogenic features. Treatment of MTT cells with DMH1, a novel BMP antagonist, suppressed proliferation and migration. To verify the clinical applicability of our findings, we evaluated a dual PI3K/mTOR inhibitor (NVP-BEZ235) in MENX-affected rats in vivo. PCCs treated with NVP-BEZ235 had decreased proliferation and integrin β1 levels, and higher apoptosis. Altogether, BMP7 activates pro-oncogenic pathways in PCC. Downstream effectors of BMP7-mediated signaling may represent novel targets for treating progressive/inoperable PCC, still orphan of effective therapy. PMID:26337467

  15. The bone morphogenic protein antagonist gremlin regulates proximal-distal patterning of the lung.

    PubMed

    Lu, M M; Yang, H; Zhang, L; Shu, W; Blair, D G; Morrisey, E E

    2001-12-01

    The proximal-distal patterning of lung epithelium involves a complex series of signaling and transcriptional events resulting in the programmed differentiation of highly specialized cells for gas exchange and surfactant protein expression essential for postnatal lung function. The BMP signaling pathway has been shown to regulate cellular differentiation in the lung as well as other tissues. In this report, we show that the can family of related BMP antagonists, including gremlin, cer-1, PRDC, and Dan are expressed in the lung during embryonic development with gremlin expression observed in the proximal airway epithelium. The role of gremlin in lung development was explored by overexpressing it in the distal lung epithelium of transgenic mice using the human SP-C promoter. SP-C/gremlin transgenic mice exhibited a disruption of the proximal-distal patterning found in the airways of the mammalian lung. Expanded expression of the proximal epithelial cell markers CC10 and HFH-4 (Foxj1) was observed in the distal regions of transgenic lungs. Furthermore, smooth muscle alpha-actin expression was observed surrounding the distal airways of SP-C/gremlin mice, indicating a proximalization of distal lung tubules. These data suggest that gremlin plays an important role in lung morphogenesis by regulating the proximal-distal patterning of the lung during development. Copyright 2001 Wiley-Liss, Inc.

  16. Bone Morphogenic Protein 4-Smad-Induced Upregulation of Platelet-Derived Growth Factor AA Impairs Endothelial Function.

    PubMed

    Hu, Weining; Zhang, Yang; Wang, Li; Lau, Chi Wai; Xu, Jian; Luo, Jiang-Yun; Gou, Lingshan; Yao, Xiaoqiang; Chen, Zhen-Yu; Ma, Ronald Ching Wan; Tian, Xiao Yu; Huang, Yu

    2016-03-01

    Bone morphogenic protein 4 (BMP4) is an important mediator of endothelial dysfunction in cardio-metabolic diseases, whereas platelet-derived growth factors (PDGFs) are major angiogenic and proinflammatory mediator, although the functional link between these 2 factors is unknown. The present study investigated whether PDGF mediates BMP4-induced endothelial dysfunction in diabetes mellitus. We generated Ad-Bmp4 to overexpress Bmp4 and Ad-Pdgfa-shRNA to knockdown Pdgfa in mice through tail intravenous injection. SMAD4-shRNA lentivirus, SMAD1-shRNA, and SMAD5 shRNA adenovirus were used for knockdown in human and mouse endothelial cells. We found that PDGF-AA impaired endothelium-dependent vasodilation in aortas and mesenteric resistance arteries. BMP4 upregulated PDGF-AA in human and mouse endothelial cells, which was abolished by BMP4 antagonist noggin or knockdown of SMAD1/5 or SMAD4. BMP4-impared relaxation in mouse aorta was also ameliorated by PDGF-AA neutralizing antibody. Tail injection of Ad-Pdgfa-shRNA ameliorates endothelial dysfunction induced by Bmp4 overexpression (Ad-Bmp4) in vivo. Serum PDGF-AA was elevated in both diabetic patients and diabetic db/db mice compared with nondiabetic controls. Pdgfa-shRNA or Bmp4-shRNA adenovirus reduced serum PDGF-AA concentration in db/db mice. PDGF-AA neutralizing antibody or tail injection with Pdgfa-shRNA adenovirus improved endothelial function in aortas and mesenteric resistance arteries from db/db mice. The effect of PDGF-AA on endothelial function in mouse aorta was also inhibited by Ad-Pdgfra-shRNA to inhibit PDGFRα. The present study provides novel evidences to show that PDGF-AA impairs endothelium-dependent vasodilation and PDGF-AA mediates BMP4-induced adverse effect on endothelial cell function through SMAD1/5- and SMAD4-dependent mechanisms. Inhibition of PGDF-AA ameliorates vascular dysfunction in diabetic mice. © 2016 American Heart Association, Inc.

  17. Combination of Controllably Released Platelet Rich Plasma Alginate Beads and Bone Morphogenic Protein-2 Gene-Modified Mesenchymal Stem Cells for Bone Regeneration

    PubMed Central

    Fernandes, Gabriela; Wang, Changdong; Yuan, Xue; Liu, Zunpeng; Dziak, Rosemary; Yang, Shuying

    2016-01-01

    Background Platelet rich plasma (PRP) consists of platelet derived growth factor (PDGF) and Transforming growth factor-beta (TGF-β) that increase cell proliferation of mesenchymal stem cells (MSCs), whereas, bone morphogenic Protein-2 (BMP2) promotes osteogenic differentiation of MSCs. However, the high degradation rate of fibrin leads to the dissociation of cytokines even before the process of bone regeneration has begun. Hence, for the first time, we studied the combined effect of sustained released PRP from alginate beads on BMP2 modified MSCs osteogenic differentiation in vitro and of sustained PRP alone on a fracture defect model ex vivo as well as its effect on the calvarial suture closure. Methods After optimizing the concentration of alginate for the microspheres, the osteogenic and mineralization effect of PRP and BMP2 in combinations on MSCs was studied. A self-setting alginate hydrogel carrying PRP was tested on a femur defect model ex-vivo. The effect of PRP was studied on the closure of the embryonic (E15) mouse calvaria sutures ex vivo. Results Increase of PRP concentration promoted cellular proliferation of MSCs. 2.5%–10% of PRP displayed gradually increased ALP activity on the cells in a dose dependent manner. Sustained release PRP and BMP2 demonstrated a significantly higher ALP and mineralization activity (p<0.05). The radiographs of alginate hydrogel with PRP treated bone demonstrated a nearly complete healing of the fracture and the histological sections of the embryonic calvaria revealed that PRP leads to suture fusion. Conclusions Sustained release of PRP along with BMP2 gene modified MSCs can significantly promote bone regeneration. PMID:26745613

  18. The C-proteinase that processes procollagens to fibrillar collagens is identical to the protein previously identified as bone morphogenic protein-1.

    PubMed Central

    Li, S W; Sieron, A L; Fertala, A; Hojima, Y; Arnold, W V; Prockop, D J

    1996-01-01

    Bone morphogenic protein-1 (BMP-1) was originally identified as one of several BMPs that induced new bone formation when implanted into ectopic sites in rodents. BMP-1, however, differed from other BMPs in that it its structure was not similar to transforming growth factor beta. Instead, it had a large domain homologous to a metalloendopeptidase isolated from crayfish, an epidermal growth-factor-like domain, and three regions of internal sequence homology referred to as CUB domains. Therefore, BMP-1 was a member of the "astacin families" of zinc-requiring endopeptidases. Many astacins have been shown to play critical roles in embryonic hatching, dorsal/ventral patterning, and early developmental decisions. Here, we have obtained amino acid sequences and isolated cDNA clones for procollagen C-proteinase (EC 3.4.24.19), an enzyme that is essential for the processing of procollagens to fibrillar collagens. The results demonstrate that procollagen C-proteinase is identical to BMP-1. Images Fig. 1 Fig. 2 Fig. 3 PMID:8643539

  19. The effect of immobilization of heparin and bone morphogenic protein-2 to bovine bone substitute on osteoblast-like cell's function

    PubMed Central

    Huh, Jung-Bo; Kim, Sung-Eun; Song, Se-Kyung; Yun, Mi-Jung; Shim, Ji-Suk; Lee, Jeong-Yol

    2011-01-01

    PURPOSE This study was performed to investigate the ability of recombinant human-bone morphogenic protein-2 immobilized on a heparin-grafted bone substrate to enhance the osteoblastic functions. MATERIALS AND METHODS The Bio-Oss®, not coated with any material, was used as a control group. In rhBMP-2-Bio-Oss® group, rhBMP-2 was coated with Bio-Oss® using only deep and dry methods (50 ng/mL, 24 h). In heparinized rhBMP-2-Bio-Oss® group, dopamine was anchored to the surface of Bio-Oss®, and coated with heparin. rhBMP-2 was immobilized onto the heparinized- Bio-Oss® surface. The release kinetics of the rhBMP-2-Bio-Oss® and heparinized rhBMP-2-Bio-Oss® were analyzed using an enzyme-linked immunosorbent assay. The biological activities of the MG63 cells on the three groups were investigated via cytotoxicity assay, cell proliferation assay, alkaline phosphatase (ALP) measurement, and calcium deposition determination. Statistical comparisons were carried out by one-way ANOVA test. Differences were considered statistically significant at *P<.05 and **P<.001. RESULTS The heparinized rhBMP-2-Bio-Oss® showed more sustained release compared to the rhBMP-2-Bio-Oss® over an extended time. In the measurement of the ALP activity, the heparinized group showed a significantly higher ALP activity when compared with the non-heparinized groups (P<.05). The MG63 cells cultivated in the group with rhBMP-2 showed increased calcium deposition, and the MG63 cells from the heparinized group increased more than those that were cultivated in the non-heparinized groups. CONCLUSION Heparin increased the rhBMP-2 release amount and made sustained release possible, and heparinized Bio-Oss® with rhBMP-2 successfully improved the osteoblastic functions. PMID:22053246

  20. Bone morphogenic protein 6: a member of a novel class of prognostic factors expressed by normal and malignant plasma cells inhibiting proliferation and angiogenesis

    PubMed Central

    Seckinger, Anja; Meissner, Tobias; Moreaux, Jérôme; Goldschmidt, Hartmut; Fuhler, Gwenny M.; Benner, Axel; Hundemer, Michael; Rème, Thierry; Shaughnessy, John D.; Barlogie, Bart; Bertsch, Uta; Hillengass, Jens; Ho, Anthony D.; Pantesco, Véronique; Jauch, Anna; De Vos, John; Rossi, Jean-François; Möhler, Thomas; Klein, Bernard; Hose, Dirk

    2009-01-01

    Pathogenesis of multiple myeloma is associated with an aberrant expression of pro-proliferative, pro-angiogenic and bone-metabolism modifying factors by malignant plasma cells. Given the frequently long time-span from diagnosis of early-stage plasma cell dyscrasias to overt myeloma and the mostly low proliferation rate of malignant plasma cells, we hypothesize these likewise to express a novel class of inhibitory factors of potential prognostic relevance. Bone morphogenic proteins (BMPs) represent possible candidates as they inhibit proliferation, stimulate bone formation, and have impact on the survival of cancer patients. We assessed expression of BMPs and their receptors by Affymetrix DNA-microarrays (n=779) including CD138-purified primary myeloma cell samples (n=635) of previously untreated patients. BMP6 is the only BMP expressed by malignant and normal plasma cells. Its expression is significantly lower in proliferating myeloma cells, myeloma cell lines, or plasmablasts. BMP6 significantly inhibits proliferation of myeloma cell lines, survival of primary myeloma cells, and in vitro angiogenesis. High BMP6-expression in primary myeloma cell samples delineates significantly superior overall survival for patients undergoing high-dose chemotherapy independent of conventional prognostic factors (ISS-stage, beta-2-microglobulin). PMID:19718049

  1. Fibroblast growth factor 2 inhibits up-regulation of bone morphogenic proteins and their receptors during osteoblastic differentiation of human mesenchymal stem cells

    SciTech Connect

    Biver, Emmanuel; Soubrier, Anne-Sophie; Thouverey, Cyril; Cortet, Bernard; Broux, Odile; Caverzasio, Joseph; Hardouin, Pierre

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer FGF modulates BMPs pathway in HMSCs by down-regulating BMP/BMPR expression. Black-Right-Pointing-Pointer This effect is mediated by ERK and JNK MAPKs pathways. Black-Right-Pointing-Pointer Crosstalk between FGF and BMPs must be taken into account in skeletal bioengineering. Black-Right-Pointing-Pointer It must also be considered in the use of recombinant BMPs in orthopedic and spine surgeries. -- Abstract: Understanding the interactions between growth factors and bone morphogenic proteins (BMPs) signaling remains a crucial issue to optimize the use of human mesenchymal stem cells (HMSCs) and BMPs in therapeutic perspectives and bone tissue engineering. BMPs are potent inducers of osteoblastic differentiation. They exert their actions via BMP receptors (BMPR), including BMPR1A, BMPR1B and BMPR2. Fibroblast growth factor 2 (FGF2) is expressed by cells of the osteoblastic lineage, increases their proliferation and is secreted during the healing process of fractures or in surgery bone sites. We hypothesized that FGF2 might influence HMSC osteoblastic differentiation by modulating expressions of BMPs and their receptors. BMP2, BMP4, BMPR1A and mainly BMPR1B expressions were up-regulated during this differentiation. FGF2 inhibited HMSCs osteoblastic differentiation and the up-regulation of BMPs and BMPR. This effect was prevented by inhibiting the ERK or JNK mitogen-activated protein kinases which are known to be activated by FGF2. These data provide a mechanism explaining the inhibitory effect of FGF2 on osteoblastic differentiation of HMSCs. These crosstalks between growth and osteogenic factors should be considered in the use of recombinant BMPs in therapeutic purpose of fracture repair or skeletal bioengineering.

  2. Sustained dual release of placental growth factor-2 and bone morphogenic protein-2 from heparin-based nanocomplexes for direct osteogenesis

    PubMed Central

    Liu, Yun; Deng, Li-Zhi; Sun, Hai-Peng; Xu, Jia-Yun; Li, Yi-Ming; Xie, Xin; Zhang, Li-Ming; Deng, Fei-Long

    2016-01-01

    Objective To compare the direct osteogenic effect between placental growth factor-2 (PlGF-2) and bone morphogenic protein-2 (BMP-2). Methods Three groups of PlGF-2/BMP-2-loaded heparin–N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC) nanocomplexes were prepared: those with 0.5 μg PlGF-2; with 1.0 μg BMP-2; and with 0.5 μg PlGF-2 combined with 1.0 μg BMP-2. The loading efficiencies and release profiles of these growth factors (GFs) in this nanocomplex system were quantified using enzyme-linked immunosorbent assay, their biological activities were evaluated using cell counting kit-8, cell morphology, and cell number counting assays, and their osteogenic activities were quantified using alkaline phosphatase and Alizarin Red S staining assays. Results The loading efficiencies were more than 99% for the nanocomplexes loaded with just PlGF-2 and for those loaded with both PlGF-2 and BMP-2. For the nanocomplex loaded with just BMP-2, the loading efficiency was more than 97%. About 83%–84% of PlGF-2 and 89%–91% of BMP-2 were stably retained on the nanocomplexes for at least 21 days. In in vitro biological assays, PlGF-2 exhibited osteogenic effects comparable to those of BMP-2 despite its dose in the experiments being lower than that of BMP-2. Moreover, the results implied that heparin-based nanocomplexes encapsulating two GFs have enhanced potential in the enhancement of osteoblast function. Conclusion PlGF-2-loaded heparin–HTCC nanocomplexes may constitute a promising system for bone regeneration. Moreover, the dual delivery of PlGF-2 and BMP-2 appears to have greater potential in bone tissue regeneration than the delivery of either GFs alone. PMID:27042064

  3. Epithelial to mesenchymal transition in human skin wound healing is induced by tumor necrosis factor-alpha through bone morphogenic protein-2.

    PubMed

    Yan, Chunli; Grimm, Wesley A; Garner, Warren L; Qin, Lan; Travis, Taryn; Tan, Neiman; Han, Yuan-Ping

    2010-05-01

    Epithelial-mesenchymal transition (EMT), characterized by loss of epithelial adhesion and gain of mesenchymal features, is an important mechanism to empower epithelial cells into the motility that occurs during embryonic development and recurs in cancer and fibrosis. Whether and how EMT occurs in wound healing and fibrosis in human skin remains unknown. In this study we found that migrating epithelial cells in wound margins and deep epithelial ridges had gained mesenchymal features such as vimentin and FSP1 expression. In hypertrophic scars, EMT-related genes were elevated along with inflammatory cytokines, indicating a causal relationship. To reconstitute EMT in vitro, normal human skin and primary keratinocytes were exposed to cytokines such as tumor necrosis factor-alpha (TNF-alpha), resulting in expression of vimentin, FSP1, and matrix metalloproteinases. Moreover, TNF-alpha-induced EMT was impaired by antagonists against bone morphogen proteins (BMP) 2/4, suggesting that BMP mediates the TNF-alpha-induced EMT in human skin. Indeed, TNF-alpha could induce BMP-2 and its receptor (BMPR1A) in human skin and primary keratinocytes, and BMP2 could induce EMT features in skin explants and primary keratinocytes. In summary, we uncovered EMT features in both acute and fibrotic cutaneous wound healing of human skin. Moreover, we propose that the mesenchymal induction in wound healing is motivated by TNF-alpha, in part, through induction of BMP.

  4. Modulation of the nanometer pore size improves magnesium adsorption into mesoporous titania coatings and promotes bone morphogenic protein 4 expression in adhering osteoblasts.

    PubMed

    Cecchinato, Francesca; Atefyekta, Saba; Wennerberg, Ann; Andersson, Martin; Jimbo, Ryo; Davies, Julia R

    2016-07-01

    Mesoporous (MP) titania films used as implant coatings have recently been considered as release systems for controlled administration of magnesium to enhance initial osteoblast proliferation in vitro. Tuning of the pore size in such titania films is aimed at increasing the osteogenic potential through effects on the total loading capacity and the release profile of magnesium. In this study, evaporation-induced self-assembly (EISA) was used with different structure-directing agents to form three mesoporous films with average pore sizes of 2nm (MP1), 6nm (MP2) and 7nm (MP3). Mg adsorption and release was monitored using quartz crystal microbalance with dissipation (QCM-D). The film surfaces were characterized with atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The effect of different Mg release on osteogenesis was investigated in human fetal osteoblasts (hFOB) using pre-designed osteogenesis arrays and real-time polymerase chain reaction (RT-PCR). Results showed a sustained release from all the films investigated, with higher magnesium adsorption into MP1 and MP3 films. No significant differences were observed in the surface nanotopography of the films, either with or without the presence of magnesium. MP3 films (7nm pore size) had the greatest effect on osteogenesis, up-regulating 15 bone-related genes after 1 week of hFOB growth and significantly promoting bone morphogenic protein (BMP4) expression after 3 weeks of growth. The findings indicate that the increase in pore width on the nano scale significantly enhanced the bioactivity of the mesoporous coating, thus accelerating osteogenesis without creating differences in surface roughness. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. Bone Morphogenic Protein 4 Mediates NOX1-Dependent eNOS Uncoupling, Endothelial Dysfunction, and COX2 Induction in Type 2 Diabetes Mellitus.

    PubMed

    Youn, Ji-Youn; Zhou, Jun; Cai, Hua

    2015-08-01

    We have recently shown that angiotensin II-mediated uncoupling of endothelial nitric oxide synthase (eNOS) contributes to endothelial dysfunction in streptozotocin-induced type 1 diabetes mellitus. However, it has remained unclear whether and how eNOS uncoupling occurs in type 2 diabetes mellitus (T2DM) and the consequences of such in regulating vascular function. Here we investigated a role of bone morphogenic protein (BMP)-4 in mediating eNOS uncoupling, endothelial dysfunction, and inflammation in db/db mice. Circulating levels of BMP4 were markedly elevated in db/db mice but not in mice with type 1 diabetes mellitus, in which angiotensin II levels were significantly increased. Infusion of BMP4 antagonist noggin into db/db mice (15 μg/kg/day, 4 weeks) abolished eNOS uncoupling activity while restoring tetrahydrobiopterin (H(4)B) bioavailability. The impaired endothelium-dependent vasorelaxation in db/db aortas was significantly improved by noggin infusion. Exposure of aortic endothelial cells to BMP4 (50 ng/mL, 24 hours) resulted in eNOS uncoupling, which was attenuated by H(4)B precursor sepiapterin or small interfering RNA silencing nicotinamide adenine dinucleotide phosphate oxidase isoform 1 (NOX1). Interestingly, BMP4-dependent NOX1 up-regulation was abrogated by sepiapterin, implicating a NOX1-uncoupled eNOS-NOX1 feed-forward loop. BMP4 induction of cyclooxygenase 2 (COX2) expression and vascular cell adhesion protein 1 was found in db/db mice. Consistently, COX2 was up-regulated by BMP4 in endothelial cells, which was attenuated by sepiapterin, implicating an upstream role of eNOS uncoupling in COX2-mediated inflammatory activation. Taken together, our data for the first time reveal a novel role of BMP4 in inducing NOX1-dependent eNOS uncoupling in T2DM, which may promote development of novel therapeutics restoring endothelial function in T2DM.

  6. Complications associated with the use of recombinant human bone morphogenic protein 2 in ridge augmentation: A case report.

    PubMed

    Dragonas, Panagiotis; Palin, Charles; Khan, Saba; Gajendrareddy, Praveen; Weiner, Whitney

    2017-08-04

    This case report aims to describe in detail a complication associated with resorption of regenerated bone following implant placement and ridge augmentation using rhBMP-2 in combination with allograft and xenograft. Bilateral maxillary sinus and ridge augmentation procedures were completed using rhBMP-2 combined with allograft and xenograft. Five months later, significant bone augmentation was achieved which allowed for the placement of 4 implants. Upon stage 2 surgery, significant dehiscence was noted in all implants. Treatment steps to address this complication included implant removal, guided bone regeneration with xenograft only and placement of new implants followed by soft tissue grafting. At the time of publication, this patient is status one and a half years post case completion with maintenance of therapy outcomes. Off-label use of rhBMP-2 has gained significant acceptance in implant dentistry. However, there is limited evidence regarding bone maturation process when rhBMP-2 is combined with other biomaterials. More research may be needed regarding timing and process of bone healing in the presence of rhBMP-2, in an effort to avoid surgical complications.

  7. Genetic Variants in the Bone Morphogenic Protein Gene Family Modify the Association between Residential Exposure to Traffic and Peripheral Arterial Disease

    PubMed Central

    Ward-Caviness, Cavin K.; Neas, Lucas M.; Blach, Colette; Haynes, Carol S.; LaRocque-Abramson, Karen; Grass, Elizabeth; Dowdy, Elaine; Devlin, Robert B.; Diaz-Sanchez, David; Cascio, Wayne E.; Lynn Miranda, Marie; Gregory, Simon G.; Shah, Svati H.; Kraus, William E.; Hauser, Elizabeth R.

    2016-01-01

    There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been rarely performed particularly in the case of air pollution exposures. We performed race-stratified genome-wide gene-environment interaction association studies on European-American (EA, N = 1623) and African-American (AA, N = 554) cohorts to investigate the joint influence of common single nucleotide polymorphisms (SNPs) and residential exposure to traffic (“traffic exposure”)—a recognized vascular disease risk factor—on peripheral arterial disease (PAD). Traffic exposure was estimated via the distance from the primary residence to the nearest major roadway, defined as the nearest limited access highways or major arterial. The rs755249-traffic exposure interaction was associated with PAD at a genome-wide significant level (P = 2.29x10-8) in European-Americans. Rs755249 is located in the 3’ untranslated region of BMP8A, a member of the bone morphogenic protein (BMP) gene family. Further investigation revealed several variants in BMP genes associated with PAD via an interaction with traffic exposure in both the EA and AA cohorts; this included interactions with non-synonymous variants in BMP2, which is regulated by air pollution exposure. The BMP family of genes is linked to vascular growth and calcification and is a novel gene family for the study of PAD pathophysiology. Further investigation of BMP8A using the Genotype Tissue Expression Database revealed multiple variants with nominally significant (P < 0.05) interaction P-values in our EA cohort were significant BMP8A eQTLs in tissue types highlight relevant for PAD such as rs755249 (tibial nerve, eQTL P = 3.6x10-6) and rs1180341 (tibial artery, eQTL P = 5.3x10-6). Together these results reveal a novel gene, and possibly gene

  8. Genetic Variants in the Bone Morphogenic Protein Gene Family Modify the Association between Residential Exposure to Traffic and Peripheral Arterial Disease.

    PubMed

    Ward-Caviness, Cavin K; Neas, Lucas M; Blach, Colette; Haynes, Carol S; LaRocque-Abramson, Karen; Grass, Elizabeth; Dowdy, Elaine; Devlin, Robert B; Diaz-Sanchez, David; Cascio, Wayne E; Lynn Miranda, Marie; Gregory, Simon G; Shah, Svati H; Kraus, William E; Hauser, Elizabeth R

    2016-01-01

    There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been rarely performed particularly in the case of air pollution exposures. We performed race-stratified genome-wide gene-environment interaction association studies on European-American (EA, N = 1623) and African-American (AA, N = 554) cohorts to investigate the joint influence of common single nucleotide polymorphisms (SNPs) and residential exposure to traffic ("traffic exposure")-a recognized vascular disease risk factor-on peripheral arterial disease (PAD). Traffic exposure was estimated via the distance from the primary residence to the nearest major roadway, defined as the nearest limited access highways or major arterial. The rs755249-traffic exposure interaction was associated with PAD at a genome-wide significant level (P = 2.29x10-8) in European-Americans. Rs755249 is located in the 3' untranslated region of BMP8A, a member of the bone morphogenic protein (BMP) gene family. Further investigation revealed several variants in BMP genes associated with PAD via an interaction with traffic exposure in both the EA and AA cohorts; this included interactions with non-synonymous variants in BMP2, which is regulated by air pollution exposure. The BMP family of genes is linked to vascular growth and calcification and is a novel gene family for the study of PAD pathophysiology. Further investigation of BMP8A using the Genotype Tissue Expression Database revealed multiple variants with nominally significant (P < 0.05) interaction P-values in our EA cohort were significant BMP8A eQTLs in tissue types highlight relevant for PAD such as rs755249 (tibial nerve, eQTL P = 3.6x10-6) and rs1180341 (tibial artery, eQTL P = 5.3x10-6). Together these results reveal a novel gene, and possibly gene family

  9. Bones Morphogenic Protein-4 and retinoic acid combined treatment comparative analysis for in vitro differentiation potential of murine mesenchymal stem cells derived from bone marrow and adipose tissue into germ cells.

    PubMed

    Shirzeily, Maryam H; Khanlarkhani, Neda; Amidi, Fardin; Shirzeily, Farshad H; Aval, Fereydoon S; Sobhani, Aligholi

    2017-09-18

    Nowadays, infertility is no longer considered as an unsolvable disorder due to progresses in germ cells derived from stem lineage with diverse origins. Technical and ethical challenges push researchers to investigate various tissue sources to approach more efficient gametes. The purpose of the current study is to investigate the efficacy of a combined medium, retinoic acid (RA) together with Bone Morphogenic Protein-4 (BMP4), on differentiation of Bone Marrow Mesenchymal Stem Cells (BMMSCs) and adipose-derived mesenchymal stem cells (ADMSCs) into germ cells. Murine MSCs were obtained from both Bone Marrow (BM) and Adipose Tissue (AT) samples and were analyzed for surface markers to get further verification of their nature. BMMSCs and ADMSCs were induced into osteogenic and adipogenic lineage cells respectively, to examine their multipotency. They were finally differentiated into germ cells using media enriched with BMP4 for 4 days followed by addition of RA for 7 days (11 days in total). Analyzing of differentiation potential of BMMSCs- and ADMSCs were performed via Immunofluorescence, Flowcytometry and Real time-PCR techniques for germ cell-specific markers (Mvh, Dazl, Stra8 and Scp3). Mesenchymal surface markers (CD90 and CD44) were expressed on both BMMSCs and ADMSCs, while endothelial and hematopoietic cell markers (CD31 and CD45) had no expression. Finally, all germ-specific markers were expressed in both BM and AT. Although germ cells differentiated from ADMSCs showed faster growth and proliferation as well as easy collection, they significantly expressed germ-specific markers lower than BMMSCs. This suggests stronger differentiation potential of murine BMMSCs than ADMSCs. © 2017 Wiley Periodicals, Inc.

  10. Synergistic effect of recombinant human bone morphogenic protein-7 and osteogenic differentiation medium on human bone-marrow-derived mesenchymal stem cells in vitro.

    PubMed

    Zhi, Lianteng; Chen, Chao; Pang, Xiaoli; Uludag, Hasan; Jiang, Hongxing

    2011-12-01

    The purpose of this study was to investigate the effect of recombinant human bone morphogenetic protein-7 (rhBMP-7) with or without osteogenic differentiation medium (ODM) on osteogenic differentiation of primary human bone-marrow-derived mesenchymal stem cells (hBMSCs) in vitro. The hBMSCs were isolated from medullary reaming tissue. At 80% confluence, hBMSCs were treated with different concentrations of rhBMP-7 with and without ODM. Alkaline phosphatase (ALP) activity, calcium deposition and messenger RNA (mRNA) expression of osteocalcin (OC) and osteopontin (OPN) were examined. ALP activity and calcium deposits in hBMSC culture were significantly increased by rhBMP-7 at 0.1 μg/ml (0.23 ± 0.07 IU and 28.9 ± 4.2 mg/dl) and 1.0 μg/ml (0.32 ± 0.03 IU and 38.7 ± 3.0 mg/dl), respectively, in the presence of ODM, showing a clearly dose-dependent osteoblastic differentiation. However, the same dose of 0.1 μg/ml rhBMP-7 without ODM and ODM alone induced low level of ALP and calcium deposits, indicating a synergistic effect of rhBMP-7 and ODM on committed osteogenic differentiation. Quantitative real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis showed up-regulated OC and OPN mRNA levels, corroborating the synergistic effect of rhBMP-7 and ODM. Our study showed that rhBMP-7 with ODM created a synergistic effect on up-regulation of osteogenic genes as well as osteogenic differentiation of primary hBMSCs in vitro. In the presence of ODM, the lowest concentration of rhBMP-7 needed to induce significant osteogenic differentiation of hBMSCs was 0.1 μg/ml.

  11. The influence of exercise on bone morphogenic enzyme activity of immature equine subchondral bone.

    PubMed

    van de Lest, Chris H A; Brama, Pieter A J; van Weeren, P R

    2003-01-01

    This study aimed at the determination of the influence of exercise on the levels of a number of bone morphogenic enzymes in subchondral bone and at the comparison of these data with other (subchondral) bone-related parameters that have been investigated in the same experimental population.Forty-three foals were reared until weaning at 5 months of age under similar conditions, except for the type and amount of exercise. Fifteen foals remained at pasture (Pasture group and also control group), 14 foals were kept in box stalls (Box group) and 14 foals were kept in the same box stalls but were subjected daily to an increasing number of gallop sprints (Training group). After weaning 8 foals from each group were euthanised. All remaining 19 animals were housed together in a loose box with access to a small paddock to study a possible reversibility of exercise-induced effects. Post mortem subchondral bone samples were collected from the femoropatellar joint and analysed for the bone morphogenic enzymes alkaline phosphatase (ALP), tartrate resistant acid phosphatase (TRAP) and lysyl oxidase (LO). Data were compared to calcium content, numbers of collagen cross-links, bone mineral density (BMD) and cross-sectional area (CSA) collected in other bone-related studies in the same group of experimental animals. At 5 months of age, ALP levels were significantly lower and TRAP levels higher in both the Box and the Training group, making the ALP : TRAP ratio reversed in relation to the Pasture group. LO levels were lower in the Box group only. The ALP and TRAP data corresponded with changes in CSA, but not with calcium and BMD, the levels of which were the same in the Training and Pasture groups. The LO levels corresponded nicely with hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) cross-links. At 11 months of age ALP and TRAP levels had reached similar levels in most groups, normalising the ALP : TRAP ratio. TRAP levels in the former Training group lagged somewhat behind

  12. Biomaterial delivery of morphogens to mimic the natural healing cascade in bone

    PubMed Central

    Mehta, Manav; Schmidt-Bleek, Katharina; Duda, Georg N; Mooney, David J

    2012-01-01

    Complications in treatment of large bone defects using bone grafting still remain. Our understanding of the endogenous bone regeneration cascade has inspired the exploration of a wide variety of growth factors (GFs) in an effort to mimic the natural signaling that controls bone healing. Biomaterial-based delivery of single exogenous GFs has shown therapeutic efficacy, and this likely relates to its ability to recruit and promote replication of cells involved in tissue development and the healing process. However, as the natural bone healing cascade involves the action of multiple factors, each acting in a specific spatiotemporal pattern, strategies aiming to mimic the critical aspects of this process will likely benefit from the usage of multiple therapeutic agents. This article reviews the current status of approaches to deliver single GFs, as well as ongoing efforts to develop sophisticated delivery platforms to deliver multiple lineage-directing morphogens (multiple GFs) during bone healing. PMID:22626978

  13. Morphogens and pattern formation.

    PubMed

    Neumann, C; Cohen, S

    1997-08-01

    Morphogen gradient theories have enjoyed considerable popularity since the beginning of this century, but conclusive evidence for a role of morphogens in controlling multicellular development have been elusive. Recently, work on three secreted signalling proteins. Activin in Xenopus, and Wingless and Dpp in Drosophila, has strongly suggested that these proteins function as morphogens. In order to define a factor as a morphogen, it is necessary to show firstly, that it has a direct effect on target cells and secondly, that it affects the development of target cells in a concentration-dependent manner. With these criteria in mind, the evidence available for a variety of proposed morphogens is discussed. While the evidence is not conclusive in most of the cases considered, there is a strong case in favour of the three proteins mentioned above, which suggests that morphogens are potentially of general importance in controlling the development of multicellular organisms.

  14. Morphogenic Peptides in Regeneration of Load Bearing Tissues.

    PubMed

    Moeinzadeh, Seyedsina; Jabbari, Esmaiel

    2015-01-01

    Morphogenic proteins due to their short half-life require high doses of growth factors in regeneration of load bearing tissues which leads to undesirable side effects. These side effects include bone overgrowth, tumor formation and immune reaction. An alternative approach to reduce undesirable side effects of proteins in regenerative medicine is to use morphogenic peptides derived from the active domains of morphogenic proteins or soluble and insoluble components of the extracellular matrix of mineralized load bearing tissues to induce differentiation of progenitor cells, mineralization, maturation and bone formation. In that regard, many peptides with osteogenic activity have been discovered. These include peptides derived from bone morphogenic proteins (BMPs), those based on interaction with integrin and heparin-binding receptors, collagen derived peptides, peptides derived from other soluble ECM proteins such as bone sialoprotein and enamel matrix proteins, and those peptides derived from vasculoinductive and neuro-inductive proteins. Although these peptides show significant osteogenic activity in vitro and increase mineralization and bone formation in animal models, they are not widely used in clinical orthopedic applications as an alternative to morphogenic proteins. This is partly due to the limited availability of data on structure and function of morphogenic peptides in physiological medium, particularly in tissue engineered scaffolds. Due to their amphiphilic nature, peptides spontaneously self-assemble and aggregate into micellar structures in physiological medium. Aggregation alters the sequence of amino acids in morphogenic peptides that interact with cell surface receptors thus affecting osteogenic activity of the peptide. Aggregation and micelle formation can dramatically reduce the active concentration of morphogenic peptides with many-fold increase in peptide concentration in physiological medium. Other factors that affect bioactivity are the non

  15. Morphogen transport

    PubMed Central

    Müller, Patrick; Rogers, Katherine W.; Yu, Shuizi R.; Brand, Michael; Schier, Alexander F.

    2013-01-01

    The graded distribution of morphogens underlies many of the tissue patterns that form during development. How morphogens disperse from a localized source and how gradients in the target tissue form has been under debate for decades. Recent imaging studies and biophysical measurements have provided evidence for various morphogen transport models ranging from passive mechanisms, such as free or hindered extracellular diffusion, to cell-based dispersal by transcytosis or cytonemes. Here, we analyze these transport models using the morphogens Nodal, fibroblast growth factor and Decapentaplegic as case studies. We propose that most of the available data support the idea that morphogen gradients form by diffusion that is hindered by tortuosity and binding to extracellular molecules. PMID:23533171

  16. Cytonemes and the dispersion of morphogens

    PubMed Central

    Kornberg, Thomas B.

    2014-01-01

    Filopodia are cellular protrusions that have been implicated in many types of mechanosensory activities. Morphogens are signaling proteins that regulate the patterned development of embryos and tissues. Both have long histories that date to the beginnings of cell and developmental biology in the early 20th century, but recent findings tie specialized filopodia called cytonemes to morphogen movement and morphogen signaling. This review explores the conceptual and experimental background for a model of paracrine signaling in which the exchange of morphogens between cells is directed to sites where cytonemes directly link cells that produce morphogens to cells that receive and respond to them. PMID:25186102

  17. Regulating morphogen gradients in the Drosophila wing.

    PubMed

    Cadigan, Kenneth M

    2002-04-01

    During development, diffusible ligands, known as morphogens, are thought to move across fields of cells, regulating gene expression in a concentration dependent manner. The case for morphogens has been convincingly made for the Decapentapleigic (Dpp), Wingless (Wg) and Hedgehog (Hh) proteins in the Drosophila wing. In each case, the concentration of the morphogen's receptor plays an important role in shaping the morphogen gradient, through influencing ligand transport and/or stability. However, the relationships between each ligand/receptor pair are different. The role of heparan sulfated proteoglycans, endocytosis and novel exovesicles called argosomes in regulating morphogen distribution will also be discussed.

  18. [Role of G-protein alpha sub-units in the morphogenic processes of filamentous Ascomycota fungi].

    PubMed

    García-Rico, Ramón O; Fierro, Francisco

    The phylum Ascomycota comprises about 75% of all the fungal species described, and includes species of medical, phytosanitary, agricultural, and biotechnological importance. The ability to spread, explore, and colonise new substrates is a feature of critical importance for this group of organisms. In this regard, basic processes such as conidial germination, the extension of hyphae and sporulation, make up the backbone of development in most filamentous fungi. These processes require specialised morphogenic machinery, coordinated and regulated by mechanisms that are still being elucidated. In recent years, substantial progress has been made in understanding the role of the signalling pathway mediated by heterotrimericG proteins in basic biological processes of many filamentous fungi. This review focuses on the role of the alpha subunits of heterotrimericG proteins in the morphogenic processes of filamentous Ascomycota. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Bone morphogenetic proteins: Signaling periodontal bone regeneration and repair.

    PubMed

    Anusuya, G Sai; Kandasamy, M; Jacob Raja, S A; Sabarinathan, S; Ravishankar, P; Kandhasamy, Balu

    2016-10-01

    Bone morphogenetic proteins (BMPs) are a group of growth factors also known as cytokines and as metabologens. Originally discovered by their ability to induce the formation of bone and cartilage, BMPs are now considered to constitute a group of pivotal morphogenetic signals, orchestrating tissue architecture throughout the body. The important functioning of BMP signals in physiology is emphasized by the multitude of roles for dysregulated BMP signaling in pathological processes. A study done wherein it was found that protein extracts from bone implanted into the animals at nonbone sites induced the formation of new cartilage and bone tissue. This protein extract contained multiple factors that stimulated bone formation and was termed as "BMP." There are at least 15 different BMPs identified to date and are a part of the transforming growth factor-β super family. The most widely studied BMPs are BMP-2, BMP-3 (osteogenin), BMP-4, and BMP-7 (osteogenic protein-1). Now, any recombination type of morphogenic proteins have been synthesized, for example - recombinant human BMPs.

  20. Bone morphogenetic proteins: Signaling periodontal bone regeneration and repair

    PubMed Central

    Anusuya, G. Sai; Kandasamy, M.; Jacob Raja, S. A.; Sabarinathan, S.; Ravishankar, P.; Kandhasamy, Balu

    2016-01-01

    Bone morphogenetic proteins (BMPs) are a group of growth factors also known as cytokines and as metabologens. Originally discovered by their ability to induce the formation of bone and cartilage, BMPs are now considered to constitute a group of pivotal morphogenetic signals, orchestrating tissue architecture throughout the body. The important functioning of BMP signals in physiology is emphasized by the multitude of roles for dysregulated BMP signaling in pathological processes. A study done wherein it was found that protein extracts from bone implanted into the animals at nonbone sites induced the formation of new cartilage and bone tissue. This protein extract contained multiple factors that stimulated bone formation and was termed as “BMP.” There are at least 15 different BMPs identified to date and are a part of the transforming growth factor-β super family. The most widely studied BMPs are BMP-2, BMP-3 (osteogenin), BMP-4, and BMP-7 (osteogenic protein-1). Now, any recombination type of morphogenic proteins have been synthesized, for example - recombinant human BMPs. PMID:27829744

  1. Control of Adult Neurogenesis by Short-Range Morphogenic-Signaling Molecules.

    PubMed

    Choe, Youngshik; Pleasure, Samuel J; Mira, Helena

    2015-12-04

    Adult neurogenesis is dynamically regulated by a tangled web of local signals emanating from the neural stem cell (NSC) microenvironment. Both soluble and membrane-bound niche factors have been identified as determinants of adult neurogenesis, including morphogens. Here, we review our current understanding of the role and mechanisms of short-range morphogen ligands from the Wnt, Notch, Sonic hedgehog, and bone morphogenetic protein (BMP) families in the regulation of adult neurogenesis. These morphogens are ideally suited to fine-tune stem-cell behavior, progenitor expansion, and differentiation, thereby influencing all stages of the neurogenesis process. We discuss cross talk between their signaling pathways and highlight findings of embryonic development that provide a relevant context for understanding neurogenesis in the adult brain. We also review emerging examples showing that the web of morphogens is in fact tightly linked to the regulation of neurogenesis by diverse physiologic processes.

  2. Vaccinia virus A12L protein and its AG/A proteolysis play an important role in viral morphogenic transition

    PubMed Central

    Yang, Su Jung; Hruby, Dennis E

    2007-01-01

    Like the major vaccinia virus (VV) core protein precursors, p4b and p25K, the 25 kDa VV A12L late gene product (p17K) is proteolytically maturated at the conserved Ala-Gly-Ala motif. However, the association of the precursor and its cleavage product with the core of mature virion suggests that both of the A12L proteins may be required for virus assembly. Here, in order to test the requirement of the A12L protein and its proteolysis in viral replication, a conditional lethal mutant virus (vvtetOA12L) was constructed to regulate A12L expression by the presence or absence of an inducer, tetracycline. In the absence of tetracycline, replication of vvtetOA12L was inhibited by 80% and this inhibition could be overcome by transient expression of the wild-type copy of the A12L gene. In contrast, mutation of the AG/A site abrogated the ability of the transfected A12L gene to rescue, indicating that A12L proteolysis plays an important role in viral replication. Electron microscopy analysis of the A12L deficient virus demonstrated the aberrant virus particles, which were displayed by the AG/A site mutation. Thus, we concluded that the not only A12L protein but also its cleavage processing plays an essential role in virus morphogenic transition. PMID:17625005

  3. The Yin and Yang of bone morphogenetic proteins in cancer

    PubMed Central

    Singh, Ashok; Morris, Rebecca J.

    2010-01-01

    Bone morphogenetic proteins (BMPs) were first studied as growth factors or morphogens of the transforming growth factor-beta super family. These growth molecules, originally associated with bone and cartilage development, are now known to play important roles in morphogenesis and homeostasis in many other tissues. More recently, significant contributions of BMPs, their receptors, and interacting molecules have been linked to carcinogenesis and tumor progression. On the other hand, BMPs can sometimes play a role as a tumor suppressor. Our report highlights these new roles in the pathogenesis of cancer that may suggest novel targets for therapeutic intervention. PMID:20688557

  4. Fine-tuned shuttles for bone morphogenetic proteins.

    PubMed

    Wharton, Kristi A; Serpe, Mihaela

    2013-08-01

    Bone morphogenetic proteins (BMPs) are potent secreted signaling factors that trigger phosphorylation of Smad transcriptional regulators through receptor complex binding at the cell-surface. Resulting changes in target gene expression impact critical cellular responses during development and tissue homeostasis. BMP activity is tightly regulated in time and space by secreted modulators that control BMP extracellular distribution and availability for receptor binding. Such extracellular regulation is key for BMPs to function as morphogens and/or in the formation of morphogen activity gradients. Here, we review shuttling systems utilized to control the distribution of BMP ligands in tissue of various geometries, developing under different temporal constraints. We discuss the biological advantages for employing specific strategies for BMP shuttling and roles of varied ligand forms.

  5. Morphogen transport in epithelia

    NASA Astrophysics Data System (ADS)

    Bollenbach, T.; Kruse, K.; Pantazis, P.; González-Gaitán, M.; Jülicher, F.

    2007-01-01

    We present a general theoretical framework to discuss mechanisms of morphogen transport and gradient formation in a cell layer. Trafficking events on the cellular scale lead to transport on larger scales. We discuss in particular the case of transcytosis where morphogens undergo repeated rounds of internalization into cells and recycling. Based on a description on the cellular scale, we derive effective nonlinear transport equations in one and two dimensions which are valid on larger scales. We derive analytic expressions for the concentration dependence of the effective diffusion coefficient and the effective degradation rate. We discuss the effects of a directional bias on morphogen transport and those of the coupling of the morphogen and receptor kinetics. Furthermore, we discuss general properties of cellular transport processes such as the robustness of gradients and relate our results to recent experiments on the morphogen Decapentaplegic (Dpp) that acts in the wing disk of the fruit fly Drosophila.

  6. Root morphogenic pathways in Eucalyptus grandis are modified by the activity of protein arginine methyltransferases.

    PubMed

    Plett, Krista L; Raposo, Anita E; Bullivant, Stephen; Anderson, Ian C; Piller, Sabine C; Plett, Jonathan M

    2017-03-09

    Methylation of proteins at arginine residues, catalysed by members of the protein arginine methyltransferase (PRMT) family, is crucial for the regulation of gene transcription and for protein function in eukaryotic organisms. Inhibition of the activity of PRMTs in annual model plants has demonstrated wide-ranging involvement of PRMTs in key plant developmental processes, however, PRMTs have not been characterised or studied in long-lived tree species. Taking advantage of the recently available genome for Eucalyptus grandis, we demonstrate that most of the major plant PRMTs are conserved in E. grandis as compared to annual plants and that they are expressed in all major plant tissues. Proteomic and transcriptomic analysis in roots suggest that the PRMTs of E. grandis control a number of regulatory proteins and genes related to signalling during cellular/root growth and morphogenesis. We demonstrate here, using chemical inhibition of methylation and transgenic approaches, that plant type I PRMTs are necessary for normal root growth and branching in E. grandis. We further show that EgPRMT1 has a key role in root hair initiation and elongation and is involved in the methylation of β-tubulin, a key protein in cytoskeleton formation. Together, our data demonstrate that PRMTs encoded by E. grandis methylate a number of key proteins and alter the transcription of a variety of genes involved in developmental processes. Appropriate levels of expression of type I PRMTs are necessary for the proper growth and development of E. grandis roots.

  7. Examining Crosstalk among Transforming Growth Factor β, Bone Morphogenetic Protein, and Wnt Pathways*

    PubMed Central

    Coster, Adam D.; Thorne, Curtis A.; Wu, Lani F.; Altschuler, Steven J.

    2017-01-01

    The integration of morphogenic signals by cells is not well understood. A growing body of literature suggests increasingly complex coupling among classically defined pathways. Given this apparent complexity, it is difficult to predict where, when, or even whether crosstalk occurs. Here, we investigated pairs of morphogenic pathways, previously reported to have multiple points of crosstalk, which either do not share (TGFβ and Wnt/β-catenin) or share (TGFβ and bone morphogenetic protein (BMP)) core signaling components. Crosstalk was measured by the ability of one morphogenic pathway to cross-activate core transcription factors and/or target genes of another morphogenic pathway. In contrast to previous studies, we found a surprising absence of crosstalk between TGFβ and Wnt/β-catenin. Further, we did not observe expected cross-pathway inhibition in between TGFβ and BMP, despite the fact that both use (or could compete) for the shared component SMAD4. Critical to our assays was a separation of timescales, which helped separate crosstalk due to initial signal transduction from subsequent post-transcriptional feedback events. Our study revealed fewer (and different) inter-morphogenic pathway crosstalk connections than expected; even pathways that share components can be insulated from one another. PMID:27895117

  8. The history and histology of bone morphogenetic protein.

    PubMed

    Murray, Samuel S; Brochmann Murray, Elsa J; Wang, Jeffrey C; Duarte, Maria Eugenia Leite

    2016-07-01

    Bone morphogenetic proteins are a group of structurally related proteins within the TGF-β superfamily of proteins with a diverse repertoire of functions in embryonic and adult organisms. As is apparent from the name, the members first characterized participate in bone growth, development, and remodeling. The "morphogenic" activity per se is defined as the induction of a recapitulation of endochondral bone formation by appropriate stem cells. The regenerative capacity of bone has been recognized since ancient times. The mechanism, applications, and conceptual basis of bone transplantation, bone implantation, ectopic bone formation, and exogenously induced bone formation have been studied by many investigators for more than a century. This review examines the efforts to characterize this activity in the European and American literature over approximately the last century. Because of the inherently complex nature of the process induced by these molecules (inflammation, stem cell proliferation, cartilage differentiation, replacement of cartilage with bone) it is important to evaluate previous investigations through a histological perspective. The cellular basis of the contemporary bioassay for BMP activity is illustrated and discussed from the histological point of view.

  9. Bone morphogenetic protein

    SciTech Connect

    Xiao Yongtao; Xiang Lixin; Shao Jianzhong

    2007-10-26

    Bone morphogenetic proteins (BMPs) are multi-functional growth factors belonging to the transforming growth factor-beta superfamily. It has been demonstrated that BMPs had been involved in the regulation of cell proliferation, survival, differentiation and apoptosis. However, their hallmark ability is that play a pivotal role in inducing bone, cartilage, ligament, and tendon formation at both heterotopic and orthotopic sites. In this review, we mainly concentrate on BMP structure, function, molecular signaling and potential medical application.

  10. Bone morphogenetic proteins in orthopaedic trauma: recent clinical findings with human bone morphogenetic protein-2 (rhBMP-2).

    PubMed

    Patel, A D

    2006-01-01

    This article introduces papers based on presentations from a symposium entitled "Bone Morphogenic Protein Advisory Meeting in Orthopaedic Trauma", where recent clinical findings with human bone morphogenetic protein-2 (rhBMP-2) were reviewed. It also presents two case studies which illustrate the clinical problems with the potential morbidity of tibial fractures and the potential benefits of the use of rhBMP-2 at surgery. The article concludes with a summary of the symposium. Tibial shaft fracture repair is associated with a significant financial burden on the patient, the health care providers and the medical insurance companies. It is anticipated that the clinical advantages of rhBMP-2 could lead to cost savings both inside and outside the hospital setting.

  11. BMP 2--Genetics Institute/ Medtronic-Sofamor Danek/Integra. Bone morphogenetic protein 2--Genetics Institute/ Medtronic-Sofamor Danek/Integra, INFUSE Bone Graft, recombinant human bone morphogenetic protein 2--Genetics Institute/Medtronic-Sofamor Danek/Integra, RhBMP 2--Genetics Institute/Medtronic-Sofamor Danek/Integra.

    PubMed

    2002-01-01

    Genetics Institute (Wyeth) is collaborating with Medtronic-Sofamor Danek (which specialises in spinal reconstruction) and Integra Life Sciences to develop a BMP 2 product [INFUSE Bone Graft] for use in spinal reconstruction in North America. The INFUSE Bone Graft product has been approved for use in lumbar interbody spinal fusion procedures in the USA and is in phase III trials for use in lumbar posterolateral spinal fusion procedures. During the procedure, damaged disc is replaced with a collagen sponge (Integra's Absorbable Collagen Sponge) soaked with BMP 2, which is held in place within an implanted cage device (LT-CAGE Lumbar Tapered Fusion Devise); the fusion process subsequently requires several months to complete. However, the patient is able to leave hospital the day after the operation, whereas in conventional spinal surgery a longer recovery time is required. The procedure supersedes the use of autograft bone as it uses a recombinant human bone morphogenic protein, rhBMP-2, which induces the body to grow its own bone where required. Genetics Institute has cloned and expressed bone morphogenic proteins 1-7 and established manufacturing processes by recombinant DNA technology. Bone morphogenic proteins may be useful in the treatment of osteoporosis and orthopaedic trauma. BMP 2 is also being developed for bone regeneration as an implanted device and as an injectable formulation. Genetics Institute is also collaborating with Integra LifeSciences to develop a formulation of BMP 2 with Integra's absorbable collagen-based structures for fracture treatment, which is awaiting approval in the USA.

  12. 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.

  13. Bone Morphogenetic Proteins: Periodontal Regeneration

    PubMed Central

    Rao, Subramaniam M; Ugale, Gauri M; Warad, Shivaraj B

    2013-01-01

    Periodontitis is an infectious inflammatory disease that results in attachment loss and bone loss. Regeneration of the periodontal tissues entails de novo formation of cementum, periodontal ligament, and alveolar bone. Several different approaches are currently being explored to achieve complete, reliable, and reproducible regeneration of periodontal tissues. The therapeutic management of new bone formation is one of the key issues in successful periodontal regeneration. Bone morphogenetic proteins form a unique group of proteins within the transforming growth factor superfamily of genes and have a vital role in the regulation in the bone induction and maintenance. The activity of bone morphogenetic proteins was first identified in the 1960s, but the proteins responsible for bone induction were unknown until the purification and cloning of human bone morphogenetic proteins in the 1980s, because of their osteoinductive potential. Bone morphogenetic proteins have gained a lot of interest as therapeutic agents for treating periodontal defects. A systematic search for data related to the use of bone morphogenetic proteins for the regeneration of periodontal defects was performed to recognize studies on animals and human (PUBMED, MEDLINE, COCHRANE, and Google search). All the studies included showed noticeable regeneration of periodontal tissues with the use of BMP. PMID:23626951

  14. Special Morphological Features at the Interface of the Renal Stem/Progenitor Cell Niche Force to Reinvestigate Transport of Morphogens During Nephron Induction

    PubMed Central

    Minuth, Will W.; Denk, Lucia

    2016-01-01

    Abstract Formation of a nephron depends on reciprocal signaling of different morphogens between epithelial and mesenchymal cells within the renal stem/progenitor cell niche. Previously, it has been surmised that a close proximity exists between both involved cell types and that morphogens are transported between them by diffusion. However, actual morphological data illustrate that mesenchymal and epithelial stem/progenitor cell bodies are separated by a striking interface. Special fixation of specimens by glutaraldehyde (GA) solution including cupromeronic blue, ruthenium red, or tannic acid for electron microscopy depicts that the interface is not void but filled in extended areas by textured extracellular matrix. Surprisingly, projections of mesenchymal cells cross the interface to contact epithelial cells. At those sites the plasma membranes of a mesenchymal and an epithelial cell are connected via tunneling nanotubes. Regarding detected morphological features in combination with involved morphogens, their transport cannot longer be explained solely by diffusion. Instead, it has to be sorted according to biophysical properties of morphogens and to detected environment. Thus, the new working hypothesis is that morphogens with good solubility such as glial cell line-derived neurotrophic factor (GDNF) or fibroblast growth factors (FGFs) are transported by diffusion. Morphogens with minor solubility such as bone morphogenetic proteins (BMPs) are secreted and stored for delivery on demand in illustrated extracellular matrix. In contrast, morphogens with poor solubility such as Wnts are transported in mesenchymal cell projections along the plasma membrane or via illustrated tunneling nanotubes. However, the presence of an intercellular route between mesenchymal and epithelial stem/progenitor cells by tunneling nanotubes also makes it possible that all morphogens are transported this way. PMID:26862472

  15. Embryonic pattern scaling achieved by oppositely directed morphogen gradients.

    PubMed

    McHale, Peter; Rappel, Wouter-Jan; Levine, Herbert

    2006-05-16

    Morphogens are proteins, often produced in a localized region, whose concentrations spatially demarcate regions of differing gene expression in developing embryos. The boundaries of gene expression are typically sharp and the genes can be viewed as abruptly switching from on to off or vice versa upon crossing the boundary. To ensure the viability of the organism these boundaries must be set at certain fractional positions within the corresponding developing field. Remarkably this can be done with high precision despite the fact that the size of the developing field itself can vary widely from embryo to embryo. How this scaling is accomplished is unknown but it is clear that a single morphogen gradient is insufficient. Here we show how a pair of morphogens A and B, produced at opposite ends of a one-dimensional developing field, can solve the pattern-scaling problem. In the most promising scenario the morphogens interact via an effective annihilation reaction A + B --> slashed circle and the switch occurs according to the absolute concentration of A or B. We define a scaling criterion and show that morphogens coupled in this way can set embryonic markers across the entire developing field in proportion to the field size. This scaling occurs at developing-field sizes of a few times the morphogen decay length. The scaling criterion is not met if instead the gradients couple combinatorially such that downstream genes are regulated by the ratio A/B of the morphogen concentrations.

  16. Protein intake and bone health.

    PubMed

    Bonjour, Jean-Philippe

    2011-03-01

    Adequate nutrition plays an important role in the development and maintenance of bone structures resistant to usual mechanical stresses. In addition to calcium in the presence of an adequate supply of vitamin D, dietary proteins represent key nutrients for bone health and thereby function in the prevention of osteoporosis. Several studies point to a positive effect of high protein intake on bone mineral density or content. This fact is associated with a significant reduction in hip fracture incidence, as recorded in a large prospective study carried out in a homogeneous cohort of postmenopausal women. Low protein intake (< 0.8 g/kg body weight/day) is often observed in patients with hip fractures and an intervention study indicates that following orthopedic management, protein supplementation attenuates post-fracture bone loss, tends to increase muscle strength, and reduces medical complications and rehabilitation hospital stay. There is no evidence that high protein intake per se would be detrimental for bone mass and strength. Nevertheless, it appears reasonable to avoid very high protein diets (i. e. more than 2.0 g/kg body weight/day) when associated with low calcium intake (i. e. less than 600 mg/day). In the elderly, taking into account the attenuated anabolic response to dietary protein with ageing, there is concern that the current dietary protein recommended allowance (RDA), as set at 0.8 g/kg body weight/day, might be too low for the primary and secondary prevention of fragility fractures.

  17. Neurodegenerative and morphogenic changes in a mouse model of temporal lobe epilepsy do not depend on the expression of the calcium-binding proteins parvalbumin, calbindin, or calretinin.

    PubMed

    Bouilleret, V; Schwaller, B; Schurmans, S; Celio, M R; Fritschy, J M

    2000-01-01

    The functional role of the calcium-binding proteins parvalbumin, calretinin, and calbindin D-28k for epileptogenesis and long-term seizure-related alterations of the hippocampal formation was assessed in single- and double-knockout mice, using a kainate model of mesial temporal lobe epilepsy. The effects of a unilateral intrahippocampal injection of kainic acid were assessed at one day, 30 days, and four months post-injection, using various markers of GABAergic interneurons (GABA-transporter type 1, GABA(A)-receptor alpha1 subunit, calretinin, calbindin D-28k, somatostatin, and neuropeptide Y). Parvalbumin-deficient, parvalbumin/calbindin-deficient, and parvalbumin/calretinin-deficient mice exhibited no difference in cytoarchitecture of the hippocampal formation and in the number, distribution, or morphology of interneurons compared to wild-type mice. Likewise, mutant mice were not more vulnerable to acute kainate-induced excitotoxicity or to long-term effects of recurrent focal seizures, and exhibited the same pattern of neurochemical alterations (e.g., bilateral induction of neuropeptide Y in granule cells) and morphogenic changes (enlargement and dispersion of dentate gyrus granule cells) as wild-type animals. Quantification of interneurons revealed no significant difference in neuronal vulnerability among the genotypes.These results indicate that the calcium-binding proteins investigated here are not essential for determining the neurochemical phenotype of interneurons. Furthermore, they are not protective against kainate-induced excitotoxicity in this model, and do not appear to modulate the overall level of excitability of the hippocampus. Finally, seizure-induced changes in gene expression in granule cells, which normally express high levels of calcium-binding proteins, apparently were not affected by the gene deletions analysed.

  18. The additive effect of mesenchymal stem cells and bone morphogenetic protein 2 on γ-irradiated bone marrow in mice.

    PubMed

    Liu, Shuibing; Hu, Peizhen; Hou, Ying; Li, Peng; Li, Xubo; Tian, Qiong

    2011-12-01

    Irradiation from γ-rays can cause severe damage to bone marrow and hematopoietic tissues. Presently, the most effective method available to treat severe hematopoietic injury is a bone marrow transplant (BMT). Allogeneic BMT is a difficult technique to perform due to the differences in human leukocyte antigen proteins between the donor and recipient, with acute graft-versus-host disease being a major complication of the technique. This limits the widespread applicability of allogeneic BMT. To develop a novel treatment for acute hematopoietic damage, we transplanted bone marrow derived mesenchymal stem cells (MSCs) into recipient mice and treated them with recombinant human bone morphogenetic protein 2 (rhBMP2) to investigate whether MSCs and rhBMP2 could additively promote the restoration of hematopoietic function. MSCs are vital components of the hematopoietic microenvironment that supports hematopoiesis, and bone morphogenic protein is a key factor in hematopoiesis. The 30-day survival rate as well as the numbers of nucleated cells, bone marrow colony-forming unit-granulocyte macrophages, spleen colony-forming units and peripheral blood cells were enumerated. The results showed that, after γ-irradiation and transplantation, MSCs and rhBMP2 additively promoted and improved hematopoietic restoration and function in vivo and in vitro. This additive effect of MSCs and rhBMP2 may one day provide a novel means of treating acute hematopoietic damage.

  19. Solution-state NMR structure of the putative morphogene protein BolA (PFE0790c) from Plasmodium falciparum.

    PubMed

    Buchko, Garry W; Yee, Adelinda; Semesi, Anthony; Myler, Peter J; Arrowsmith, Cheryl H; Hui, Raymond

    2015-05-01

    Protozoa of the genus Plasmodium are responsible for malaria, which is perhaps the most important parasitic disease to infect mankind. The emergence of Plasmodium strains resistant to current therapeutics and prophylactics makes the development of new treatment strategies urgent. Among the potential targets for new antimalarial drugs is the BolA-like protein PFE0790c from Plasmodium falciparum (Pf-BolA). While the function of BolA is unknown, it has been linked to cell morphology by regulating transcription in response to stress. Using an NMR-based method, an ensemble of 20 structures of Pf-BolA was determined and deposited in the PDB (PDB entry 2kdn). The overall topology of the Pf-BolA structure, α1-β1-β2-η1-α2/η2-β3-α3, with the β-strands forming a mixed β-sheet, is similar to the fold observed in other BolA structures. A helix-turn-helix motif similar to the class II KH fold associated with nucleic acid-binding proteins is present, but contains an FXGXXXL signature sequence that differs from the GXXG signature sequence present in class II KH folds, suggesting that the BolA family of proteins may use a novel protein-nucleic acid interface. A well conserved arginine residue, Arg50, hypothesized to play a role in governing the formation of the C-terminal α-helix in the BolA family of proteins, is too distant to form polar contacts with any side chains in this α-helix in Pf-BolA, suggesting that this conserved arginine may only serve a role in guiding the orientation of this C-terminal helix in some BolA proteins. A survey of BolA structures suggests that the C-terminal helix may not have a functional role and that the third helix (α2/η2) has a `kink' that appears to be conserved among the BolA protein structures. Circular dichroism spectroscopy shows that Pf-BolA is fairly robust, partially unfolding when heated to 353 K and refolding upon cooling to 298 K.

  20. Solution-state NMR structure of the putative morphogene protein BolA (PFE0790c) from Plasmodium falciparum

    PubMed Central

    Buchko, Garry W.; Yee, Adelinda; Semesi, Anthony; Myler, Peter J.; Arrowsmith, Cheryl H.; Hui, Raymond

    2015-01-01

    Protozoa of the genus Plasmodium are responsible for malaria, which is perhaps the most important parasitic disease to infect mankind. The emergence of Plasmodium strains resistant to current therapeutics and prophylactics makes the development of new treatment strategies urgent. Among the potential targets for new antimalarial drugs is the BolA-like protein PFE0790c from Plasmodium falciparum (Pf-BolA). While the function of BolA is unknown, it has been linked to cell morphology by regulating transcription in response to stress. Using an NMR-based method, an ensemble of 20 structures of Pf-BolA was determined and deposited in the PDB (PDB entry 2kdn). The overall topology of the Pf-BolA structure, α1–β1–β2–η1–α2/η2–β3–α3, with the β-strands forming a mixed β-sheet, is similar to the fold observed in other BolA structures. A helix–turn–helix motif similar to the class II KH fold associated with nucleic acid-binding proteins is present, but contains an FXGXXXL signature sequence that differs from the GXXG signature sequence present in class II KH folds, suggesting that the BolA family of proteins may use a novel protein–nucleic acid interface. A well conserved arginine residue, Arg50, hypothesized to play a role in governing the formation of the C-terminal α-helix in the BolA family of proteins, is too distant to form polar contacts with any side chains in this α-helix in Pf-BolA, suggesting that this conserved arginine may only serve a role in guiding the orientation of this C-terminal helix in some BolA proteins. A survey of BolA structures suggests that the C-terminal helix may not have a functional role and that the third helix (α2/η2) has a ‘kink’ that appears to be conserved among the BolA protein structures. Circular dichroism spectroscopy shows that Pf-BolA is fairly robust, partially unfolding when heated to 353 K and refolding upon cooling to 298 K. PMID:25945703

  1. BMP4 acts as a dorsal telencephalic morphogen in a mouse embryonic stem cell culture system.

    PubMed

    Watanabe, Momoko; Fung, Ernest S; Chan, Felicia B; Wong, Jessica S; Coutts, Margaret; Monuki, Edwin S

    2016-12-15

    The concept of a morphogen - a molecule that specifies two or more cell fates in a concentration-dependent manner - is paradigmatic in developmental biology. Much remains unknown, however, about the existence of morphogens in the developing vertebrate central nervous system (CNS), including the mouse dorsal telencephalic midline (DTM). Bone morphogenetic proteins (BMPs) are candidate DTM morphogens, and our previous work demonstrated BMP4 sufficiency to induce one DTM cell fate - that of choroid plexus epithelial cells (CPECs) - in a mouse embryonic stem cell (mESC) culture system. Here we used BMP4 in a modified mESC culture system to derive a second DTM fate, the cortical hem (CH). CH and CPEC markers were induced by BMP4 in a concentration-dependent manner consistent with in vivo development. BMP4 concentrations that led to CH fate also promoted markers for Cajal-Retzius neurons, which are known CH derivatives. Interestingly, single BMP4 administrations also sufficed for appropriate temporal regulation of CH, CPEC, and cortical genes, with initially broad and overlapping dose-response profiles that sharpened over time. BMP4 concentrations that yielded CH- or CPEC-enriched populations also had different steady-state levels of phospho-SMAD1/5/8, suggesting that differences in BMP signaling intensity underlie DTM fate choice. Surprisingly, inactivation of the cortical selector gene Lhx2 did not affect DTM expression levels, dose-response profiles, or timing in response to BMP4, although neural progenitor genes were downregulated. These data indicate that BMP4 can act as a classic morphogen to orchestrate both spatial and temporal aspects of DTM fate acquisition, and can do so in the absence of Lhx2.

  2. BMP4 acts as a dorsal telencephalic morphogen in a mouse embryonic stem cell culture system

    PubMed Central

    Watanabe, Momoko; Fung, Ernest S.; Chan, Felicia B.; Wong, Jessica S.; Coutts, Margaret

    2016-01-01

    ABSTRACT The concept of a morphogen – a molecule that specifies two or more cell fates in a concentration-dependent manner – is paradigmatic in developmental biology. Much remains unknown, however, about the existence of morphogens in the developing vertebrate central nervous system (CNS), including the mouse dorsal telencephalic midline (DTM). Bone morphogenetic proteins (BMPs) are candidate DTM morphogens, and our previous work demonstrated BMP4 sufficiency to induce one DTM cell fate – that of choroid plexus epithelial cells (CPECs) – in a mouse embryonic stem cell (mESC) culture system. Here we used BMP4 in a modified mESC culture system to derive a second DTM fate, the cortical hem (CH). CH and CPEC markers were induced by BMP4 in a concentration-dependent manner consistent with in vivo development. BMP4 concentrations that led to CH fate also promoted markers for Cajal–Retzius neurons, which are known CH derivatives. Interestingly, single BMP4 administrations also sufficed for appropriate temporal regulation of CH, CPEC, and cortical genes, with initially broad and overlapping dose-response profiles that sharpened over time. BMP4 concentrations that yielded CH- or CPEC-enriched populations also had different steady-state levels of phospho-SMAD1/5/8, suggesting that differences in BMP signaling intensity underlie DTM fate choice. Surprisingly, inactivation of the cortical selector gene Lhx2 did not affect DTM expression levels, dose-response profiles, or timing in response to BMP4, although neural progenitor genes were downregulated. These data indicate that BMP4 can act as a classic morphogen to orchestrate both spatial and temporal aspects of DTM fate acquisition, and can do so in the absence of Lhx2. PMID:27815243

  3. Morphogens, Membranes and Mechanotransduction in Articular Cartilage

    NASA Astrophysics Data System (ADS)

    Motaung, Shirley; Chan, Stephanie; Reddi, A. Hari

    The three fundamentals of developmental biology are cell growth, cellular differentiation, and morphogenesis. Morphogenesis is the process of the generation of the shape of tissues, organs, and entire organisms from various cells. During embryonic development, as cells reproduce and divide, chemical and mechanical signals induce the cell to sort and differentiate into specialized cells. Morphogenesis is the process by which these cells become distributed and organized into tissues and organs. Morphogenetic responses can be stimulated in organisms by morphogenetic proteins, hormones, and environmental cues. There are different types of molecules that play an important role during morphogenesis and include the transcription factors and morphogens themselves.

  4. 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

  5. The Wnt and BMP Families of Signaling Morphogens at the Vertebrate Neuromuscular Junction

    PubMed Central

    Henríquez, Juan P.; Krull, Catherine E.; Osses, Nelson

    2011-01-01

    The neuromuscular junction has been extensively employed in order to identify crucial determinants of synaptogenesis. At the vertebrate neuromuscular synapse, extracellular matrix and signaling proteins play stimulatory and inhibitory roles on the assembly of functional synapses. Studies in invertebrate species have revealed crucial functions of early morphogens during the assembly and maturation of the neuromuscular junction. Here, we discuss growing evidence addressing the function of Wnt and Bone morphogenetic protein (BMP) signaling pathways at the vertebrate neuromuscular synapse. We focus on the emerging role of Wnt proteins as positive and negative regulators of postsynaptic differentiation. We also address the possible involvement of BMP pathways on motor neuron behavior for the assembly and/or regeneration of the neuromuscular junction. PMID:22272112

  6. Bone Morphogenetic Protein-9 Induces PDLSCs Osteogenic Differentiation through the ERK and p38 Signal Pathways

    PubMed Central

    Ye, Guo; Li, Conghua; Xiang, Xuerong; Chen, Chu; Zhang, Ruyi; Yang, Xia; Yu, Xuesong; Wang, Jinhua; Wang, Lan; Shi, Qiong; Weng, Yaguang

    2014-01-01

    Periodontal ligament stem cells (PDLSCs) with bone morphogenic ability are used to treat diseases such as periodontitis. Their treatment potential is increased when used in combination with proteins that induce osteogenic differentiation. For example, bone morphogenetic protein-9 (BMP9) has been found to have potent osteogenic activity. In the present study, PDLSCs were isolated from human periodontal membrane and infected with recombinant adenoviruses expressing BMP9 (Ad-BMP9). Levels of osteogenic markers such as runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP), osteopontin (OPN), and osteocalcin (OCN) as well as mineralization ability were measured. The results showed that BMP9 promoted bone formation of PDLSCs. In other experiments, SB203580 and PD98059, which are inhibitors of p38 and ERK1/2, respectively, were used to determine if these kinases are involved in the osteogenic differentiation process. The resulting protein expression profiles and osteogenic markers of PDLSCs revealed that the mitogen-activated protein kinase (MAPK) signaling pathway might play an important role in the process of BMP9-induced osteogenic differentiation of PDLSCs. PMID:25136261

  7. Vertebrate limb development: moving from classical morphogen gradients to an integrated 4-dimensional patterning system.

    PubMed

    Bénazet, Jean-Denis; Zeller, Rolf

    2009-10-01

    A wealth of classical embryological manipulation experiments taking mainly advantage of the chicken limb buds identified the apical ectodermal ridge (AER) and the zone of polarizing activity (ZPA) as the respective ectodermal and mesenchymal key signaling centers coordinating proximodistal (PD) and anteroposterior (AP) limb axis development. These experiments inspired Wolpert's French flag model, which is a classic among morphogen gradient models. Subsequent molecular and genetic analysis in the mouse identified retinoic acid as proximal signal, and fibroblast growth factors (FGFs) and sonic hedgehog (SHH) as the essential instructive signals produced by AER and ZPA, respectively. Recent studies provide good evidence that progenitors are specified early with respect to their PD and AP fates and that morpho-regulatory signaling is also required for subsequent proliferative expansion of the specified progenitor pools. The determination of particular fates seems to occur rather late and depends on additional signals such as bone morphogenetic proteins (BMPs), which indicates that cells integrate signaling inputs over time and space. The coordinate regulation of PD and AP axis patterning is controlled by an epithelial-mesenchymal feedback signaling system, in which transcriptional regulation of the BMP antagonist Gremlin1 integrates inputs from the BMP, SHH, and FGF pathways. Vertebrate limb-bud development is controlled by a 4-dimensional (4D) patterning system integrating positive and negative regulatory feedback loops, rather than thresholds set by morphogen gradients.

  8. Chordin forms a self-organizing morphogen gradient in the extracellular space between ectoderm and mesoderm in the Xenopus embryo

    PubMed Central

    Plouhinec, Jean-Louis; Zakin, Lise; Moriyama, Yuki; De Robertis, Edward M.

    2013-01-01

    The vertebrate body plan follows stereotypical dorsal–ventral (D-V) tissue differentiation controlled by bone morphogenetic proteins (BMPs) and secreted BMP antagonists, such as Chordin. The three germ layers—ectoderm, mesoderm, and endoderm—are affected coordinately by the Chordin–BMP morphogen system. However, extracellular morphogen gradients of endogenous proteins have not been directly visualized in vertebrate embryos to date. In this study, we improved immunolocalization methods in Xenopus embryos and analyzed the distribution of endogenous Chordin using a specific antibody. Chordin protein secreted by the dorsal Spemann organizer was found to diffuse along a narrow region that separates the ectoderm from the anterior endoderm and mesoderm. This Fibronectin-rich extracellular matrix is called “Brachet’s cleft” in the Xenopus gastrula and is present in all vertebrate embryos. Chordin protein formed a smooth gradient that encircled the embryo, reaching the ventral-most Brachet cleft. Depletion with morpholino oligos showed that this extracellular gradient was regulated by the Chordin protease Tolloid and its inhibitor Sizzled. The Chordin gradient, as well as the BMP signaling gradient, was self-regulating and, importantly, was able to rescale in dorsal half-embryos. Transplantation of Spemann organizer tissue showed that Chordin diffused over long distances along this signaling highway between the ectoderm and mesoderm. Chordin protein must reach very high concentrations in this narrow region. We suggest that as ectoderm and mesoderm undergo morphogenetic movements during gastrulation, cells in both germ layers read their positional information coordinately from a single morphogen gradient located in Brachet’s cleft. PMID:24284174

  9. Measurement and Perturbation of Morphogen Lifetime: Effects on Gradient Shape

    PubMed Central

    Drocco, Jeffrey A.; Grimm, Oliver; Tank, David W.; Wieschaus, Eric

    2011-01-01

    Protein lifetime is of critical importance for most biological processes and plays a central role in cell signaling and embryonic development, where it impacts the absolute concentration of signaling molecules and, potentially, the shape of morphogen gradients. Early conceptual and mathematical models of gradient formation proposed that steady-state gradients are established by an equilibration between the lifetime of a morphogen and its rates of synthesis and diffusion, though whether gradients in fact reach steady state before being read out is a matter of controversy. In any case, this class of models predicts that protein lifetime is a key determinant of both the time to steady state and the spatial extent of a gradient. Using a method that employs repeated photoswitching of a fusion of the morphogen Bicoid (Bcd) and the photoconvertible fluorescent protein Dronpa, we measure and modify the lifetime of Dronpa-Bcd in living Drosophila embryos. We find that the lifetime of Bcd is dynamic, changing from 50 min before mitotic cycle 14 to 15 min during cellularization. Moreover, by measuring total quantities of Bcd over time, we find that the gradient does not reach steady state. Finally, using a nearly continuous low-level conversion to the dark state of Dronpa-Bcd to mimic the effect of increased degradation, we demonstrate that perturbation of protein lifetime changes the characteristic length of the gradient, providing direct support for a mechanism based on synthesis, diffusion, and degradation. PMID:22004733

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

    PubMed

    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

    2012-07-24

    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.

  11. Dentin Matrix Proteins in Bone Tissue Engineering.

    PubMed

    Ravindran, Sriram; George, Anne

    2015-01-01

    Dentin and bone are mineralized tissue matrices comprised of collagen fibrils and reinforced with oriented crystalline hydroxyapatite. Although both tissues perform different functionalities, they are assembled and orchestrated by mesenchymal cells that synthesize both collagenous and noncollagenous proteins albeit in different proportions. The dentin matrix proteins (DMPs) have been studied in great detail in recent years due to its inherent calcium binding properties in the extracellular matrix resulting in tissue calcification. Recent studies have shown that these proteins can serve both as intracellular signaling proteins leading to induction of stem cell differentiation and also function as nucleating proteins in the extracellular matrix. These properties make the DMPs attractive candidates for bone and dentin tissue regeneration. This chapter will provide an overview of the DMPs, their functionality and their proven and possible applications with respect to bone tissue engineering.

  12. Dentin Matrix Proteins in Bone Tissue Engineering

    PubMed Central

    Ravindran, Sriram

    2016-01-01

    Dentin and bone are mineralized tissue matrices comprised of collagen fibrils and reinforced with oriented crystalline hydroxyapatite. Although both tissues perform different functionalities, they are assembled and orchestrated by mesenchymal cells that synthesize both collagenous and noncollagenous proteins albeit in different proportions. The dentin matrix proteins (DMPs) have been studied in great detail in recent years due to its inherent calcium binding properties in the extracellular matrix resulting in tissue calcification. Recent studies have shown that these proteins can serve both as intracellular signaling proteins leading to induction of stem cell differentiation and also function as nucleating proteins in the extracellular matrix. These properties make the DMPs attractive candidates for bone and dentin tissue regeneration. This chapter will provide an overview of the DMPs, their functionality and their proven and possible applications with respect to bone tissue engineering. PMID:26545748

  13. Morpheus unbound: reimagining the morphogen gradient.

    PubMed

    Lander, Arthur D

    2007-01-26

    The theory that the spatial organization of cell fate is orchestrated by gradients of diffusing molecules was a major contribution to 20th century developmental biology. Although the existence of morphogens is no longer in doubt, studies on the formation and function of their gradients have yielded far more puzzles than answers. On close inspection, every morphogen gradient seems to use a rich array of regulatory mechanisms, suggesting that the tasks carried out by such systems are far more extensive than previously thought.

  14. Use of recombinant human bone morphogenetic protein (rhBMP2) in bilateral alveolar ridge augmentation: case report.

    PubMed

    Katanec, Davor; Granić, Marko; Majstorović, Martina; Trampus, Zdenko; Pandurić, Dragana Gabrić

    2014-03-01

    In recent years, the delivery of osteoinductive factors such as bone morphogenic proteins (BMPs) has become an alternative approach to traditional bone grafting due to their capacity to produce bone healing and new bone formation. BMP-2 has proved to possess the highest osteoinductive potential among BMPs. The case reported the clinical use of recombinant human BMP-2 for bilateral vertical alveolar ridge augmentation. In a case of 61 year-old patient with a significant bilateral vertical bony deficiency of the mandible, rhBMP-2 administered via an absorbable collagen sponge carrier (ACS) was used for bilateral alveolar ridge bone induction. Augmented sites were covered and fixed with titanium mesh. Augmented sites were reopened 6 months after surgery. Titanium membrane and retaining screws were removed and three dental implants were placed. The tissue samples for the histologic analysis were harvested. Following 3 months healing period, the submerged implants were uncovered and restored with zirconium-ceramic crowns. Cone beam computed tomography (CBCT), panoramix and 3D radiographic evaluation were obtained prior to and after the surgical procedure. Vertical gain of the bone was 5.5 mm on the left and 5 mm on the right side, with 6 mm width of the bone. Histologic analysis revealed formation of mature trabecular bone with signs of osteoblastic proliferation. Implant stability quotient (ISQ) values were in the range between 69 and 75 for all three implants. No suppuration, gingival recession or pain were present 24 months after surgery. Vertical bone augmentation using rhBMP-2 is optional treatment modality to consider when planning dental implant placement in sites where severe vertical insufficiency exists.

  15. Morphogens Reveal the Appearance and Functions of lncRNAs.

    PubMed

    Anastassova-Kristeva, Marlene

    2015-07-01

    During the first meiotic division, the entire genetic information from DNA is transcribed into mRNPs and stored in the ovoplasm in the form of mRNP particles. The 39 human nuclear HOX proteins bind to thousands of mRNAs transcribed repeatedly by lampbrush chromosomes. HOX proteins suppress processing and translation. The RNP particles containing lncRNAs+HOX proteins are the morphogens ("transcription factors," more precisely differentiation factors), which unlock new genes and differentiate the cells of the developing embryo. All ovoplasmic mRNAs bound with HOX proteins do not translate and are noncoding. Their destination (purpose) is transportation of HOX proteins to the complementary DNAs and cell differentiation.

  16. Fat facets deubiquitylation of Medea/Smad4 modulates interpretation of a Dpp morphogen gradient.

    PubMed

    Stinchfield, Michael J; Takaesu, Norma T; Quijano, Janine C; Castillo, Ashley M; Tiusanen, Nina; Shimmi, Osamu; Enzo, Elena; Dupont, Sirio; Piccolo, Stefano; Newfeld, Stuart J

    2012-08-01

    The ability of secreted Transforming Growth Factor β (TGFβ) proteins to act as morphogens dictates that their influence be strictly regulated. Here, we report that maternally contributed fat facets (faf; a homolog of USP9X/FAM) is essential for proper interpretation of the zygotic Decapentaplegic (Dpp) morphogen gradient that patterns the embryonic dorsal-ventral axis. The data suggest that the loss of faf reduces the activity of Medea (a homolog of Smad4) below the minimum necessary for adequate Dpp signaling and that this is likely due to excessive ubiquitylation on a specific lysine. This study supports the hypothesis that the control of cellular responsiveness to TGFβ signals at the level of Smad4 ubiquitylation is a conserved mechanism required for proper implementation of a morphogen gradient.

  17. Multifunctional ECM proteins in bone and teeth.

    PubMed

    Ravindran, Sriram; George, Anne

    2014-07-15

    The extracellular matrix (ECM) of all tissues and organs is a highly organized and complex structure unique to the specific organ type. The ECM contains structural and functional proteins that define cellular function, organization, behavior and ultimately organ characteristics and function. The ECM was initially thought to contain only a specific set of secretory proteins. However, our group and several other groups have shown that the ECM contains functional proteins that have been previously defined as solely intracellular. In the present review, we have focused on the ECM of mineralized tissues namely bone and dentin. We provide here, a brief review of some non-classical ECM proteins that have been shown to possess both intra and extracellular roles in the formation of these mineralized matrices.

  18. Role of morphogens in neural crest cell determination.

    PubMed

    Jones, Natalie C; Trainor, Paul A

    2005-09-15

    The neural crest is a transient, migratory cell population found in all vertebrate embryos that generate a diverse range of cell and tissue derivatives including, but not limited, to the neurons and glia of the peripheral nervous system, smooth muscle, connective tissue, melanocytes, craniofacial cartilage, and bone. Over the past few years, many studies have provided tremendous insights into understanding the mechanisms regulating the induction and migration of neural crest cell development. This review highlights the surprising and perhaps unexpected roles for morphogens in these distinct processes. A comparison of studies performed in several different vertebrates emphasizes the requirement for coordination between multiple signaling pathways in the induction and migration of neural crest cells in the developing embryo. (c) 2005 Wiley Periodicals, Inc.

  19. Bovine bone morphogenetic protein-induced dentinogenesis.

    PubMed

    Lianjia, Y; Yuhao, G; White, F H

    1993-10-01

    Differentiation of odontoblasts is important for dentin formation in tooth germs and mature teeth. Although previous reports have indicated that there may be a kind of inductive agent that could induce mesenchymal cells in dental pulps to differentiate into odontoblasts, and secrete dentin matrix, the primary inductive factor of odontoblasts has not been found. Bone morphogenetic protein (BMP), which induces the formation of cartilage and bone when implanted in muscle tissue, is found in dentin matrix. The relationship between the differentiation of odontoblasts and BMP was observed by means of immunohistochemical staining with monoclonal antibody (MAb) against BMP in dental pulp tissue and cell culture; [3H]thymidine incorporation; and measurement of alkaline phosphatase activity. The conclusions are: (1) BMP exists in odontoblasts, ameloblasts, and dentin matrix (the positive reaction in ameloblasts appeared earlier and remained stronger); (2) BMP promotes incorporation of [3H]thymidine and increases the activity of alkaline phosphatase in cultured dental pulp cells; (3) BMP-induced dental pulp cells in dental pulp tissue cultures differentiate from mesenchymal to odontoblast-like cells; and (4) BMP induces formation of osteodentin and tubular dentin when used as a dental capping agent of dogs' teeth. Bone morphogenetic protein plays an important role in differentiation of odontoblasts and might be one of the inductive agents of odontoblasts. Further investigations of BMP as a biologic dental capping agent are warranted.

  20. [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.

  1. The interaction between dietary protein and bone health.

    PubMed

    Jesudason, David; Clifton, Peter

    2011-01-01

    The role of dietary protein in bone health has been controversial. On the one hand, a plentiful supply of dietary amino acids has been considered important to support bone remodeling while on the other hand there have been concerns that the dietary acid load associated with protein consumption promotes hypercalciuria and loss of bone calcium stores. This article reviews the effect of dietary protein on bone mass and bone density, and the effect on markers of bone resorption and formation and also on fracture risk, looking at both cross-sectional and longitudinal studies and examining both meat and vegetable protein including soy and milk basic protein. The results are not entirely consistent and suggest that the interaction between dietary protein and other components in a mixed diet, such as calcium intake and vegetables and fruit to neutralize acid, are important and may determine whether high-protein diets are beneficial to bone health. Overall the results suggest that dietary protein has a modest beneficial effect on bone markers and bone density. This effect has yet to be consistently linked to reduced fracture risk, probably because of the role of other etiological factors such as the risk of falls. There is not enough evidence currently to suggest that animal protein is superior or inferior to vegetable protein, or that milk or soy protein, respectively, is more favorable than other protein sources.

  2. Analysis of bone protein and mineral composition in bone disease using synchrotron infrared microspectroscopy

    NASA Astrophysics Data System (ADS)

    Miller, Lisa M.; Hamerman, David; Chance, Mark R.; Carlson, Cathy S.

    1999-10-01

    by lower mineral/protein ratios and higher acid phosphate content. This immature bone may also be a symptom of slower bone formation rates related to estrogen deficiency.

  3. Studies of morphogens: keep calm and carry on.

    PubMed

    Stathopoulos, Angelike; Iber, Dagmar

    2013-10-01

    Morphogens are signaling factors that direct cell fate and tissue development at a distance from their source, and various modes of transport and interpretation have been suggested for morphogens. The recent EMBO Workshop on 'Morphogen gradients', which took place in Oxford, UK in June 2013, centered on the formation and interpretation of such morphogen gradients during development. This meeting allowed an exchange of views in light of recent results. Here, we provide a brief overview of the talks, organized in relation to several major themes of discussion at the meeting: (1) morphogen gradient formation; (2) morphogen gradient interpretation; (3) signaling networks and feedback in morphogenesis; (4) emergence of patterns; (5) scaling of patterns; (6) the control of growth; and (7) new techniques in the field.

  4. Cross-talk between bone morphogenetic proteins and inflammatory pathways.

    PubMed

    van der Kraan, Peter M; Davidson, Esmeralda N Blaney

    2015-11-23

    Pro-inflammatory cytokines and bone morphogenetic proteins are generally studied separately and considered to be elements of different worlds, immunology and developmental biology. Varas and colleagues report that these factors show cross-talk in rheumatoid arthritis synoviocytes. They show that pro-inflammatory cytokines not only stimulate the production of bone morphogenetic proteins but that these endogenously produced bone morphogenetic proteins interfere with the effects of pro-inflammatory cytokines on synoviocytes.

  5. Bone morphogenetic protein-2 gene controls tooth root development in coordination with formation of the periodontium

    PubMed Central

    Rakian, Audrey; Yang, Wu-Chen; Gluhak-Heinrich, Jelica; Cui, Yong; Harris, Marie A; Villarreal, Demitri; Feng, Jerry Q; MacDougall, Mary; Harris, Stephen E

    2013-01-01

    Formation of the periodontium begins following onset of tooth-root formation in a coordinated manner after birth. Dental follicle progenitor cells are thought to form the cementum, alveolar bone and Sharpey's fibers of the periodontal ligament (PDL). However, little is known about the regulatory morphogens that control differentiation and function of these progenitor cells, as well as the progenitor cells involved in crown and root formation. We investigated the role of bone morphogenetic protein-2 (Bmp2) in these processes by the conditional removal of the Bmp2 gene using the Sp7-Cre-EGFP mouse model. Sp7-Cre-EGFP first becomes active at E18 in the first molar, with robust Cre activity at postnatal day 0 (P0), followed by Cre activity in the second molar, which occurs after P0. There is robust Cre activity in the periodontium and third molars by 2 weeks of age. When the Bmp2 gene is removed from Sp7+ (Osterix+) cells, major defects are noted in root, cellular cementum and periodontium formation. First, there are major cell autonomous defects in root-odontoblast terminal differentiation. Second, there are major alterations in formation of the PDLs and cellular cementum, correlated with decreased nuclear factor IC (Nfic), periostin and α-SMA+ cells. Third, there is a failure to produce vascular endothelial growth factor A (VEGF-A) in the periodontium and the pulp leading to decreased formation of the microvascular and associated candidate stem cells in the Bmp2-cKOSp7-Cre-EGFP. Fourth, ameloblast function and enamel formation are indirectly altered in the Bmp2-cKOSp7-Cre-EGFP. These data demonstrate that the Bmp2 gene has complex roles in postnatal tooth development and periodontium formation. PMID:23807640

  6. A method for whole protein isolation from human cranial bone.

    PubMed

    Lyon, Sarah M; Mayampurath, Anoop; Rogers, M Rose; Wolfgeher, Donald J; Fisher, Sean M; Volchenboum, Samuel L; He, Tong-Chuan; Reid, Russell R

    2016-12-15

    The presence of the dense hydroxyapatite matrix within human bone limits the applicability of conventional protocols for protein extraction. This has hindered the complete and accurate characterization of the human bone proteome thus far, leaving many bone-related disorders poorly understood. We sought to refine an existing method of protein extraction from mouse bone to extract whole proteins of varying molecular weights from human cranial bone. Whole protein was extracted from human cranial suture by mechanically processing samples using a method that limits protein degradation by minimizing heat introduction to proteins. The presence of whole protein was confirmed by western blotting. Mass spectrometry was used to sequence peptides and identify isolated proteins. The data have been deposited to the ProteomeXchange with identifier PXD003215. Extracted proteins were characterized as both intra- and extracellular and had molecular weights ranging from 9.4 to 629 kDa. High correlation scores among suture protein spectral counts support the reproducibility of the method. Ontology analytics revealed proteins of myriad functions including mediators of metabolic processes and cell organelles. These results demonstrate a reproducible method for isolation of whole protein from human cranial bone, representing a large range of molecular weights, origins and functions.

  7. High-strength silk protein scaffolds for bone repair.

    PubMed

    Mandal, Biman B; Grinberg, Ariela; Gil, Eun Seok; Panilaitis, Bruce; Kaplan, David L

    2012-05-15

    Biomaterials for bone tissue regeneration represent a major focus of orthopedic research. However, only a handful of polymeric biomaterials are utilized today because of their failure to address critical issues like compressive strength for load-bearing bone grafts. In this study development of a high compressive strength (~13 MPa hydrated state) polymeric bone composite materials is reported, based on silk protein-protein interfacial bonding. Micron-sized silk fibers (10-600 µm) obtained utilizing alkali hydrolysis were used as reinforcement in a compact fiber composite with tunable compressive strength, surface roughness, and porosity based on the fiber length included. A combination of surface roughness, porosity, and scaffold stiffness favored human bone marrow-derived mesenchymal stem cell differentiation toward bone-like tissue in vitro based on biochemical and gene expression for bone markers. Further, minimal in vivo immunomodulatory responses suggested compatibility of the fabricated silk-fiber-reinforced composite matrices for bone engineering applications.

  8. Novel approaches to bone grafting: porosity, bone morphogenetic proteins, stem cells, and the periosteum.

    PubMed

    Petrochenko, Peter; Narayan, Roger J

    2010-01-01

    The disadvantages involving the use of a patient's own bone as graft material have led surgeons to search for alternative materials. In this review, several characteristics of a successful bone graft material are discussed. In addition, novel synthetic materials and natural bone graft materials are being considered. Various factors can determine the success of a bone graft substitute. For example, design considerations such as porosity, pore shape, and interconnection play significant roles in determining graft performance. The effective delivery of bone morphogenetic proteins and the ability to restore vascularization also play significant roles in determining the success of a bone graft material. Among current approaches, shorter bone morphogenetic protein sequences, more efficient delivery methods, and periosteal graft supplements have shown significant promise for use in autograft substitutes or autograft extenders.

  9. Bone protein extraction without demineralization utilizing principles from hydroxyapatite chromatography

    PubMed Central

    Cleland, Timothy P.; Vashishth, Deepak

    2014-01-01

    Historically, extraction of bone proteins has relied on the use of demineralization to better retrieve proteins from the extracellular matrix; however, demineralization can be a slow process that restricts subsequent analysis of the samples. Here, we developed a novel protein extraction method that does not use demineralization, but utilizes a methodology from hydroxyapatite chromatography where high concentrations of ammonium phosphate and ammonium bicarbonate are used to extract bone proteins. We report that this method has a higher yield than previously published small-scale extant bone extractions, with and without demineralization. Furthermore, after digestion with trypsin and subsequent HPLC-MS/MS analysis, we were able to detect several extracellular matrix and vascular proteins in addition to collagen I and osteocalcin. Our new method has the potential to isolate proteins in a short period (4 hrs) and provide information about bone proteins that may be lost during demineralization or with the use of denaturing agents. PMID:25535955

  10. A strategy to quantitate global phosphorylation of bone matrix proteins.

    PubMed

    Sroga, Grażyna E; Vashishth, Deepak

    2016-04-15

    Current studies of protein phosphorylation focus primarily on the importance of specific phosphoproteins and their landscapes of phosphorylation in the regulation of different cellular functions. However, global changes in phosphorylation of extracellular matrix phosphoproteins measured "in bulk" are equally important. For example, correct global phosphorylation of different bone matrix proteins is critical to healthy tissue biomineralization. To study changes of bone matrix global phosphorylation, we developed a strategy that combines a procedure for in vitro phosphorylation/dephosphorylation of fully mineralized bone in addition to quantitation of the global phosphorylation levels of bone matrix proteins. For the first time, we show that it is possible to enzymatically phosphorylate/dephosphorylate fully mineralized bone originating from either cadaveric human donors or laboratory animals (mice). Using our strategy, we detected the difference in the global phosphorylation levels of matrix proteins isolated from wild-type and osteopontin knockout mice. We also observed that the global phosphorylation levels of matrix proteins isolated from human cortical bone were lower than those isolated from trabecular bone. The developed strategy has the potential to open new avenues for studies on the global phosphorylation of bone matrix proteins and their role in biomineralization as well for other tissues/cells and protein-based materials.

  11. The CCN Family Proteins: Modulators of Bone Development and Novel Targets in Bone-Associated Tumors

    PubMed Central

    Chen, Po-Chun; Cheng, Hsu-Chen; Yang, Shun-Fa; Tang, Chih-Hsin

    2014-01-01

    The CCN family of proteins is composed of six extracellular matrix-associated proteins that play crucial roles in skeletal development, wound healing, fibrosis, and cancer. Members of the CCN family share four conserved cysteine-rich modular domains that trigger signal transduction in cell adhesion, migration, proliferation, differentiation, and survival through direct binding to specific integrin receptors and heparan sulfate proteoglycans. In the present review, we discuss the roles of the CCN family proteins in regulating resident cells of the bone microenvironment. In vertebrate development, the CCN family plays a critical role in osteo/chondrogenesis and vasculo/angiogenesis. These effects are regulated through signaling via integrins, bone morphogenetic protein, vascular endothelial growth factor, Wnt, and Notch via direct binding to CCN family proteins. Due to the important roles of CCN family proteins in skeletal development, abnormal expression of CCN proteins is related to the tumorigenesis of primary bone tumors such as osteosarcoma, Ewing sarcoma, and chondrosarcoma. Additionally, emerging studies have suggested that CCN proteins may affect progression of secondary metastatic bone tumors by moderating the bone microenvironment. CCN proteins could therefore serve as potential therapeutic targets for drug development against primary and metastatic bone tumors. PMID:24551846

  12. The CCN family proteins: modulators of bone development and novel targets in bone-associated tumors.

    PubMed

    Chen, Po-Chun; Cheng, Hsu-Chen; Yang, Shun-Fa; Lin, Chiao-Wen; Tang, Chih-Hsin

    2014-01-01

    The CCN family of proteins is composed of six extracellular matrix-associated proteins that play crucial roles in skeletal development, wound healing, fibrosis, and cancer. Members of the CCN family share four conserved cysteine-rich modular domains that trigger signal transduction in cell adhesion, migration, proliferation, differentiation, and survival through direct binding to specific integrin receptors and heparan sulfate proteoglycans. In the present review, we discuss the roles of the CCN family proteins in regulating resident cells of the bone microenvironment. In vertebrate development, the CCN family plays a critical role in osteo/chondrogenesis and vasculo/angiogenesis. These effects are regulated through signaling via integrins, bone morphogenetic protein, vascular endothelial growth factor, Wnt, and Notch via direct binding to CCN family proteins. Due to the important roles of CCN family proteins in skeletal development, abnormal expression of CCN proteins is related to the tumorigenesis of primary bone tumors such as osteosarcoma, Ewing sarcoma, and chondrosarcoma. Additionally, emerging studies have suggested that CCN proteins may affect progression of secondary metastatic bone tumors by moderating the bone microenvironment. CCN proteins could therefore serve as potential therapeutic targets for drug development against primary and metastatic bone tumors.

  13. Role of Regulators of G Protein Signaling Proteins in Bone Physiology and Pathophysiology

    PubMed Central

    Jules, Joel; Yang, Shuying; Chen, Wei; Li, Yi-Ping

    2016-01-01

    Regulators of G protein signaling (RGS) proteins enhance the intrinsic GTPase activity of α subunits of the heterotrimeric G protein complex of G protein-coupled receptors (GPCRs) and thereby inactivate signal transduction initiated by GPCRs. The RGS family consists of nearly 37 members with a conserved RGS homology domain which is critical for their GTPase accelerating activity. RGS proteins are expressed in most tissues, including heart, lung, brain, kidney, and bone and play essential roles in many physiological and pathological processes. In skeletal development and bone homeostasis as well as in many bone disorders, RGS proteins control the functions of various GPCRs, including the parathyroid hormone receptor type 1 and calcium-sensing receptor and also regulate various critical signaling pathways, such as Wnt and calcium oscillations. This chapter will discuss the current findings on the roles of RGS proteins in regulating signaling of key GPCRs in skeletal development and bone homeostasis. We also will examine the current updates of RGS proteins’ regulation of calcium oscillations in bone physiology and highlight the roles of RGS proteins in selected bone pathological disorders. Despite the recent advances in bone and mineral research, RGS proteins remain understudied in the skeletal system. Further understanding of the roles of RGS proteins in bone should not only provide great insights into the molecular basis of various bone diseases but also generate great therapeutic drug targets for many bone diseases. PMID:26123302

  14. Effects of bone morphogenic protein 4 (BMP4) and its inhibitor, Noggin, on in vitro maturation and culture of bovine preimplantation embryos.

    PubMed

    La Rosa, Isabel; Camargo, Luiz S A; Pereira, Michele M; Fernandez-Martin, Rafael; Paz, Dante A; Salamone, Daniel F

    2011-02-01

    BMP4 is a member of the transforming growth factor beta (TGFbeta) superfamily and Noggin is a potent BMP inhibitor that exerts its function by binding to BMPs preventing interactions with its receptors. The aim of this work was to investigate the role of BMP4 and Noggin, on oocytes in vitro maturation (m experiments) and embryos in vitro development (c experiments) of bovine. For m experiments, COCs were collected from slaughterhouse ovaries and in vitro matured in TCM with 100 ng/ml of either BMP4 or Noggin. After 24 h, the nuclear stage of the oocytes was determined by staining with Hoechst 33342. In addition, RT-qPCR was performed on MII oocytes to study the relative concentration of ZAR1, GDF9, BAX, MATER and HSP70 transcripts. Treated oocytes were submitted to parthenogenic activation (PA) or in vitro fertilization (IVF) and cultured in CR2. For c experiments, non-treated matured oocytes were submitted to PA or IVF to generate embryos that were exposed to 100 ng/ml of BMP4 or Noggin in CR2 until day nine of culture. Cleavage, blastocyst and hatching rates, expression pattern of the transcription factor Oct-4 in blastocysts and embryo cell number at day two and nine post-activation or fertilization were evaluated. We found that Noggin, as BMP4, did not affect oocyte nuclear maturation. Noggin supplementation up-regulated the expression of HSP70 and MATER genes in matured oocytes. Moreover, BMP4 during maturation increased the proportion of Oct-4 positive cells in parthenogenic embryos. On the other hand, when Noggin was added to embryo culture medium, developmental rates of parthenogenic and in vitro fertilized embryos were reduced. However, BMP4 addition decreases the development only for in vitro fertilized embryos. BMP4 and Noggin during culture reduced the proportion of Oct-4-expressing cells. Our results show that BMP4 is implicated in bovine oocytes maturation and embryo development. Moreover, our findings demonstrate, for the first time, that a correct balance of BMP signaling is needed for proper pre-implantation development of bovine embryos.

  15. Co-delivery of platelet-derived growth factor (PDGF-BB) and bone morphogenic protein (BMP-2) coated onto heparinized titanium for improving osteoblast function and osteointegration.

    PubMed

    Kim, Sung Eun; Yun, Young-Pil; Lee, Jae Yong; Shim, June-Sung; Park, Kyeongsoon; Huh, Jung-Bo

    2015-12-01

    The aim of this study was to improve osteoblast function by delivering two growth factors, PDGF-BB and BMP-2, incorporated onto heparinized titanium (Hep-Ti) substrate. To achieve co-delivery of PDGF-BB and BMP-2, the surface of anodized Ti was immobilized with heparin, and then the two growth factors were coated onto the Hep-Ti surface. Incorporation of the two growth factors onto Hep-Ti was evaluated by SEM and XPS. Incorporated PDGF-BB and BMP-2 were released from the Hep-Ti substrate in a sustained manner. In vitro studies revealed that osteoblasts grown on PDGF-BB- and BMP-2-immobilized Hep-Ti increased ALP activity, calcium deposition, osteocalcin and osteopontin levels as compared to those grown on PDGF-BB alone- or BMP-2 alone-immobilized Hep-Ti. These results suggested that co-delivery of PDGF-BB and BMP-2 using Hep-Ti substrate will be a promising material for the enhancement of osteoblast function and osteointegration. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Genetic Variants in the Bone Morphogenic Protein Gene Family Modify the Association between Residential Exposure to Traffic and Peripheral Arterial Disease

    EPA Science Inventory

    There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been ...

  17. Genetic Variants in the Bone Morphogenic Protein Gene Family Modify the Association between Residential Exposure to Traffic and Peripheral Arterial Disease

    EPA Science Inventory

    There is a growing literature indicating that genetic variants modify many of the associations between environmental exposures and clinical outcomes, potentially by increasing susceptibility to these exposures. However, genome-scale investigations of these interactions have been ...

  18. Congenital Bone Fractures in Spinal Muscular Atrophy: Functional Role for SMN Protein in Bone Remodeling

    PubMed Central

    Shanmugarajan, Srinivasan; Swoboda, Kathryn J.; Iannaccone, Susan T.; Ries, William L.; Maria, Bernard L.; Reddy, Sakamuri V.

    2009-01-01

    Spinal muscular atrophy is the second most common fatal childhood disorder. Core clinical features include muscle weakness caused by degenerating lower motor neurons and a high incidence of bone fractures and hypercalcemia. Fractures further compromise quality of life by progression of joint contractures or additional loss of motor function. Recent observations suggest that bone disease in spinal muscular atrophy may not be attributed entirely to lower motor neuron degeneration. The presence of the spinal muscular atrophy disease-determining survival motor neuron gene (SMN), SMN expression, and differential splicing in bone-resorbing osteoclasts was recently discovered. Its ubiquitous expression and the differential expression of splice variants suggest that SMN has specific roles in bone cell function. SMN protein also interacts with osteoclast stimulatory factor. Mouse models of human spinal muscular atrophy disease suggest a potential role of SMN protein in skeletal development. Dual energy x-ray absorptiometry analysis demonstrated a substantial decrease in total bone area and poorly developed caudal vertebra in the mouse model. These mice also had pelvic bone fractures. Studies delineating SMN signaling mechanisms and gene transcription in a cell-specific manner will provide important molecular insights into the pathogenesis of bone disease in children with spinal muscular atrophy. Moreover, understanding bone remodeling in spinal muscular atrophy may lead to novel therapeutic approaches to enhance skeletal health and quality of life. This article reviews the skeletal complications associated with spinal muscular atrophy and describes a functional role for SMN protein in osteoclast development and bone resorption activity. PMID:17761651

  19. The Structure and Function of Non-Collagenous Bone Proteins

    NASA Technical Reports Server (NTRS)

    Hook, Magnus; McQuillan, David J.

    1997-01-01

    The research done under the cooperative research agreement for the project titled 'The structure and function of non-collagenous bone proteins' represented the first phase of an ongoing program to define the structural and functional relationships of the principal noncollagenous proteins in bone. An ultimate goal of this research is to enable design and execution of useful pharmacological compounds that will have a beneficial effect in treatment of osteoporosis, both land-based and induced by long-duration space travel. The goals of the now complete first phase were as follows: 1. Establish and/or develop powerful recombinant protein expression systems; 2. Develop and refine isolation and purification of recombinant proteins; 3. Express wild-type non-collagenous bone proteins; 4. Express site-specific mutant proteins and domains of wild-type proteins to enhance likelihood of crystal formation for subsequent solution of structure.

  20. Erythropoietin modulates the structure of bone morphogenetic protein 2-engineered cranial bone.

    PubMed

    Sun, Hongli; Jung, Younghun; Shiozawa, Yusuke; Taichman, Russell S; Krebsbach, Paul H

    2012-10-01

    The ideally engineered bone should have similar structural and functional properties to the native tissue. Although structural integrity is critical for functional bone regeneration, we know less about modulating the structural properties of the engineered bone elicited by bone morphogenetic protein (BMP) than efficacy and safety. Erythropoietin (Epo), a primary erythropoietic hormone, has been used to augment blood transfusion in orthopedic surgery. However, the effects of Epo on bone regeneration are not well known. Here, we determined the role of Epo in BMP2-induced bone regeneration using a cranial defect model. Epo administration improved the quality of BMP2-induced bone and more closely resembled natural cranial bone with a higher bone volume (BV) fraction and lower marrow fraction when compared with BMP2 treatment alone. Epo increased red blood cells (RBCs) in peripheral blood and also increased hematopoietic and mesenchymal stem cell (MSC) populations in bone marrow. Consistent with our previous work, Epo increased osteoclastogenesis both in vitro and in vivo. Results from a metatarsal organ culture assay suggested that Epo-promoted osteoclastogenesis contributed to angiogenesis because angiogenesis was blunted when osteoclastogenesis was blocked by alendronate (ALN) or osteoprotegerin (OPG). Earlier calcification of BMP2-induced temporary chondroid tissue was observed in the Epo+BMP group compared to BMP2 alone. We conclude that Epo significantly enhanced the outcomes of BMP2-induced cranial bone regeneration in part through its actions on osteoclastogenesis and angiogenesis.

  1. Novel silk protein barrier membranes for guided bone regeneration.

    PubMed

    Smeets, Ralf; Knabe, Christine; Kolk, Andreas; Rheinnecker, Michael; Gröbe, Alexander; Heiland, Max; Zehbe, Rolf; Sachse, Manuela; Große-Siestrup, Christian; Wöltje, Michael; Hanken, Henning

    2016-10-12

    This study assesses the biocompatibility of novel silk protein membranes with and without modification, and evaluates their effect on facilitating bone formation and defect repair in guided bone regeneration. Two calvarian bone defects 12 mm in diameter were created in each of a total of 38 rabbits. Four different types of membranes, (silk-, hydroxyapatite-modified silk-, β-TCP-modified silk- and commonly clinically used collagen-membranes) were implanted to cover one of the two defects in each animal. Histologic analysis did not show any adverse tissue reactions in any of the defect sites indicating good biocompatibility of all silk protein membranes. Histomorphometric and histologic evaluation revealed that collagen and β-TCP modified silk membranes supported bone formation (collagen: bone area fraction p = 0.025; significant; β-TCP modified silk membranes bone area fraction: p = 0.24, not significant), guided bone regeneration and defect bridging. The bone, which had formed in defects covered by β-TCP modified silk membranes, displayed a more advanced stage of bone tissue maturation with restoration of the original calvarial bone microarchitecture when compared to the bone which had formed in defects, for which any of the other test membranes were used. Micro-CT analysis did not reveal any differences in the amount of bone formation between defects with and without membranes. In contrast to the collagen membranes, β-TCP modified silk membranes were visible in all cases and may therefore be advantageous for further supporting bone formation beyond 10 weeks and preventing soft tissue ingrowth from the periphery. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2016.

  2. Dietary protein: an essential nutrient for bone health.

    PubMed

    Bonjour, Jean-Philippe

    2005-12-01

    Nutrition plays a major role in the development and maintenance of bone structures resistant to usual mechanical loadings. In addition to calcium in the presence of an adequate vitamin D supply, proteins represent a key nutrient for bone health, and thereby in the prevention of osteoporosis. In sharp opposition to experimental and clinical evidence, it has been alleged that proteins, particularly those from animal sources, might be deleterious for bone health by inducing chronic metabolic acidosis which in turn would be responsible for increased calciuria and accelerated mineral dissolution. This claim is based on an hypothesis that artificially assembles various notions, including in vitro observations on the physical-chemical property of apatite crystal, short term human studies on the calciuric response to increased protein intakes, as well as retrospective inter-ethnic comparisons on the prevalence of hip fractures. The main purpose of this review is to analyze the evidence that refutes a relation of causality between the elements of this putative patho-physiological "cascade" that purports that animal proteins are causally associated with an increased incidence of osteoporotic fractures. In contrast, many experimental and clinical published data concur to indicate that low protein intake negatively affects bone health. Thus, selective deficiency in dietary proteins causes marked deterioration in bone mass, micro architecture and strength, the hallmark of osteoporosis. In the elderly, low protein intakes are often observed in patients with hip fracture. In these patients intervention study after orthopedic management demonstrates that protein supplementation as given in the form of casein, attenuates post-fracture bone loss, increases muscles strength, reduces medical complications and hospital stay. In agreement with both experimental and clinical intervention studies, large prospective epidemiologic observations indicate that relatively high protein intakes

  3. Studies of Bone Morphogenetic Protein based Surgical Repair

    PubMed Central

    Lo, Kevin W.-H.; Ulery, Bret D.; Ashe, Keshia M.; Laurencin, Cato T.

    2012-01-01

    Over the past several decades, recombinant human bone morphogenetic proteins (rhBMPs) have been the most extensively studied and widely used osteoinductive agents for clinical bone repair. Since rhBMP-2 and rhBMP-7 were approved by the U.S. Food and Drug Administration for certain clinical uses, millions of patients worldwide have been treated with rhBMPs for various musculoskeletal disorders. Current clinical applications include treatment of long bone fracture non-unions, spinal surgeries, and oral maxillofacial surgeries. Considering the growing number of recent publications related to clincal research of rhBMPs, there exists enormous promise for these proteins to be used in bone regenerative medicine. The authors take this opportunity to review the rhBMP literature paying specific attention to the current applications of rhBMPs in bone repair and spine surgery. The prospective future of rhBMPs delivered in combination with tissue engineered scaffolds is also reviewed. PMID:22512928

  4. Matricellular proteins as regulators of cancer metastasis to bone

    PubMed Central

    Trotter, Timothy N.; Yang, Yang

    2016-01-01

    Metastasis is the major cause of the death in cancer patients, and a frequent site of metastasis for many cancers is the bone marrow. Therefore, understanding the mechanisms underlying the metastatic process is necessary for future prevention and treatment. The tumor microenvironment is now known to play a role in the metastatic cascade, both at the primary tumor and in metastatic sites, and includes both cellular and non-cellular components. The extracellular matrix (ECM) provides structural support and signaling cues to cells. One particular group of molecules associated with the ECM, known as matricellular proteins, modulate multiple aspects of tumor biology, including growth, migration, invasion, angiogenesis and metastasis. These proteins are also important for normal function in the bone by regulating bone formation and bone resorption. Recent studies have described a link between some of these proteins and metastasis of various tumors to the bone. The aim of this review is to summarize what is currently known about matricellular protein influence on bone metastasis. Particular attention to the contribution of both tumor cells and non-malignant cells in the bone has been given. PMID:26807761

  5. Milk basic protein increases bone mineral density and improves bone metabolism in healthy young women.

    PubMed

    Uenishi, K; Ishida, H; Toba, Y; Aoe, S; Itabashi, A; Takada, Y

    2007-03-01

    Effect of milk basic protein on bone metabolism in healthy young women. Milk has more beneficial effects on bone health than other food sources. Recent in vitro and in vivo studies have shown that milk whey protein, especially its basic protein fraction (milk basic protein, MBP), contains several components capable of promoting bone formation and inhibiting bone resorption. The object of this study was to examine the effect of MBP on the bone mineral density and bone metabolism of healthy young women. Thirty-five healthy young women were randomly assigned to treatment with either placebo or MBP (40 mg per day) for 6 months. The bone mineral density (BMD) of the lumbar vertebrae L2-L4 of each subject was measured by dual-energy X-ray absorptiometry (DXA) at 0 and 6 months of treatment. Serum and urine indexes of bone metabolism were measured at 0, 3 and 6 months. All subjects completed the study in accordance with the protocol. The mean rate of gain of lumbar BMD in the MBP group (1.57%) was significantly higher than in the placebo group (0.13%, P=0.042). When compared with the placebo group, urinary cross-linked N-telopeptides of type-I collagen (NTx) were significantly decreased, and serum osteocalcin was significantly increased in the MBP group at 6 months. These results suggested that MBP supplementation was effective in increasing BMD in young women and that this increase in BMD may be primarily mediated through the promotion of bone formation and inhibition of bone resorption by MBP supplementation.

  6. 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

  7. Evaluation of milk basic protein supplementation on bone density and bone metabolism in Chinese young women.

    PubMed

    Zou, Zhi-Yong; Lin, Xiao-Ming; Xu, Xian-Rong; Xu, Rui; Ma, Le; Li, Ying; Wang, Ming-Fang

    2009-08-01

    Milk is a good source of bioavailable calcium compared with other foods. Recent in vitro and in vivo studies have shown that milk whey protein, especially its basic protein fraction (milk basic protein, MBP), contains several components capable of promoting bone formation and inhibiting bone resorption. The objective of this study was to examine the effects of MBP on bone mineral density (BMD) and bone metabolism of healthy young women. Eighty-four healthy young women were randomly assigned to three groups: control group, whole milk group or MBP group treated with milk containing 40 mg MBP for 8 months. The bone mineral density of total body, the lumbar vertebrae L2-L4 and the left forearm of each subject were measured by dual-energy X-ray absorptiometry (DEXA) at 0 and 8 months of treatment. Serum indexes of bone metabolism were measured at 0, 3, 6 and 8 months. Eighty-one subjects who completed the study in accordance with the protocol were included in the analysis. Total BMD in all groups significantly increased compared with baseline values. However, no significant difference on the mean rate of gain of total BMD was observed among the MBP group (2.19%), the whole milk group (2.63%) and the control group (1.61%). Serum cross-linked N-teleopeptides of type-I collagen (NTx) in MBP group at 8 months and in whole milk group at 6 months were significantly decreased from baseline. There were no significant differences between whole milk group and MBP group; however, after combining the milk groups, NTx had significantly decreased from baseline. No significant increase was observed in serum bone-specific alkaline phosphatase (BAP) in both whole milk group and MBP group. No significant effect of MBP on bone mineral density and bone metabolism was observed, but milk supplementation was effective in suppressing bone resorption.

  8. Dietary protein, calcium metabolism and bone health in humans

    USDA-ARS?s Scientific Manuscript database

    Protein is the major structural constituent of bone (50% by volume). But it is also a major source of metabolic acid, especially protein from animal sources because it contains sulfur amino acids that generate sulfuric acid. Increased potential renal acid load has been closely associated with increa...

  9. Transgenic overexpression of bone morphogenetic protein 11 propeptide in skeleton enhances bone formation

    USDA-ARS?s Scientific Manuscript database

    Bone morphogenetic protein 11 (BMP11) is a key regulatory protein in skeletal development. BMP11 propeptide has been shown to antagonize GDF11 activity in vitro. To explore the role of BMP11 propeptide in skeletal formation in vivo, we generated transgenic mice with skeleton-specific overexpression...

  10. Delivery of bone morphogenetic protein-2 and substance P using graphene oxide for bone regeneration

    PubMed Central

    La, Wan-Geun; Jin, Min; Park, Saibom; Yoon, Hee-Hun; Jeong, Gun-Jae; Bhang, Suk Ho; Park, Hoyoung; Char, Kookheon; Kim, Byung-Soo

    2014-01-01

    In this study, we demonstrate that graphene oxide (GO) can be used for the delivery of bone morphogenetic protein-2 (BMP-2) and substance P (SP), and that this delivery promotes bone formation on titanium (Ti) implants that are coated with GO. GO coating on Ti substrate enabled a sustained release of BMP-2. BMP-2 delivery using GO-coated Ti exhibited a higher alkaline phosphatase activity in bone-forming cells in vitro compared with bare Ti. SP, which is known to recruit mesenchymal stem cells (MSCs), was co-delivered using Ti or GO-coated Ti to further promote bone formation. SP induced the migration of MSCs in vitro. The dual delivery of BMP-2 and SP using GO-coated Ti showed the greatest new bone formation on Ti implanted in the mouse calvaria compared with other groups. This approach may be useful to improve osteointegration of Ti in dental or orthopedic implants. PMID:24872706

  11. Preservation of the bone protein osteocalcin in dinosaurs

    NASA Astrophysics Data System (ADS)

    Muyzer, Gerard; Sandberg, Philip; Knapen, Marjo H. J.; Vermeer, Cees; Collins, Matthew; Westbroek, Peter

    1992-10-01

    Two different immunological assays were used to identify the remains of a bone matrix protein, osteocalcin (OC), in the bones of dinosaurs and other fossil vertebrates. Antibodies raised against OC from modern vertebrates showed strong immunological cross-reactivity with modern and relatively young fossil samples and significant reactions with some of the dinosaur bone extracts. The presence of OC was confirmed by the detection of a peptide-bound, uniquely vertebrate amino acid, γcarboxyglutamic acid (Gla). Preservation of OC in fossil bones appears to be strongly dependent on the burial history and not simply on age. These results extend the range of protein preservation in the geologic record and provide a first step toward a molecular phylogeny of the dinosaurs.

  12. Oxidized alginate hydrogels for bone morphogenetic protein-2 delivery in long bone defects.

    PubMed

    Priddy, Lauren B; Chaudhuri, Ovijit; Stevens, Hazel Y; Krishnan, Laxminarayanan; Uhrig, Brent A; Willett, Nick J; Guldberg, Robert E

    2014-10-01

    Autograft treatment of large bone defects and fracture non-unions is complicated by limited tissue availability and donor site morbidity. Polymeric biomaterials such as alginate hydrogels provide an attractive tissue engineering alternative due to their biocompatibility, injectability, and tunable degradation rates. Irradiated RGD-alginate hydrogels have been used to deliver proteins such as bone morphogenetic protein-2 (BMP-2), to promote bone regeneration and restoration of function in a critically sized rat femoral defect model. However, slow degradation of irradiated alginate hydrogels may impede integration and remodeling of the regenerated bone to its native architecture. Oxidation of alginate has been used to promote degradation of alginate matrices. The objective of this study was to evaluate the effects of alginate oxidation on BMP-2 release and bone regeneration. We hypothesized that oxidized-irradiated alginate hydrogels would elicit an accelerated release of BMP-2, but degrade faster in vivo, facilitating the formation of higher quality, more mature bone compared to irradiated alginate. Indeed, oxidation of irradiated alginate did accelerate in vitro BMP-2 release. Notably, the BMP-2 retained within both constructs was bioactive at 26days, as observed by induction of alkaline phosphatase activity and positive Alizarin Red S staining of MC3T3-E1 cells. From the in vivo study, robust bone regeneration was observed in both groups through 12weeks by radiography, micro-computed tomography analyses, and biomechanical testing. Bone mineral density was significantly greater for the oxidized-irradiated alginate group at 8weeks. Histological analyses of bone defects revealed enhanced degradation of oxidized-irradiated alginate and suggested the presence of more mature bone after 12weeks of healing.

  13. Bone morphogenetic protein-2-encapsulated grafted-poly-lactic acid-polycaprolactone nanoparticles promote bone repair.

    PubMed

    Xu, Xiaojun; Yang, Jun; Ding, Lifeng; Li, Jianjun

    2015-01-01

    The aim of this study is to test the efficacy of a novel tissue-engineered bone in repairing bone defects, using poly-lactic-acid-polycaprolactone (PLA-PCL) scaffolding seeded with PEG-bone morphogenetic protein-2 (BMP-2)-transfected rBMSCs (rabbit bone marrow stromal cells). The rBMSCs were transfected with PEG/BMP-2 or liposome/BMP-2, and then implanted into a PLA-PCL tissue-engineered bone. The protein level of BMP-2 was assessed by Western blot analysis and immunohistochemistry. ELISA was used to measure the amount of BMP-2 secreted in the culture media. The mRNA level of BMP-2 and osteocalcin was assayed quantitatively by real-time PCR. The middle portion of the bilateral radius in New Zealand rabbits was excised and implanted with tissue-engineered bone, and the modified areas were monitored by X-ray, hematoxylin-eosin staining, and immunohistochemistry staining of BMP-2. PEG-BMP-2 nanoparticles (NPs) and BMP-2-loaded PEG-PLA-PCL tissue-engineered bones were successfully constructed. The novel PEG-PLA-PCL NPs/DNA complex was a superior option for transfecting BMP-2 in rBMSCs compared to normal liposomes Moreover, the mRNA level of osteocalcin and alkaline phosphatase activity was also elevated upon transfection of BMP-2-encapsulated NPs. In vivo implants with BMP-2-carried tissue-engineered bone exhibited dramatic augmentation of BMP-2 and effective bone formation in the rabbit ectopic model. The PEG-PLA-PCL NPs/BMP-2 complex had an advantageous effect on bone repair, which provided an important theoretic basis for potential clinical treatments.

  14. High-strength silk protein scaffolds for bone repair

    PubMed Central

    Mandal, Biman B.; Grinberg, Ariela; Seok Gil, Eun; Panilaitis, Bruce; Kaplan, David L.

    2012-01-01

    Biomaterials for bone tissue regeneration represent a major focus of orthopedic research. However, only a handful of polymeric biomaterials are utilized today because of their failure to address critical issues like compressive strength for load-bearing bone grafts. In this study development of a high compressive strength (~13 MPa hydrated state) polymeric bone composite materials is reported, based on silk protein-protein interfacial bonding. Micron-sized silk fibers (10–600 µm) obtained utilizing alkali hydrolysis were used as reinforcement in a compact fiber composite with tunable compressive strength, surface roughness, and porosity based on the fiber length included. A combination of surface roughness, porosity, and scaffold stiffness favored human bone marrow-derived mesenchymal stem cell differentiation toward bone-like tissue in vitro based on biochemical and gene expression for bone markers. Further, minimal in vivo immunomodulatory responses suggested compatibility of the fabricated silk-fiber-reinforced composite matrices for bone engineering applications. PMID:22552231

  15. The synergistic induction of bone formation by the osteogenic proteins of the TGF-β supergene family.

    PubMed

    Ripamonti, Ugo; Parak, Ruqayya; Klar, Roland M; Dickens, Caroline; Dix-Peek, Thérèse; Duarte, Raquel

    2016-10-01

    haematopoietic bone marrow that forms by day 15 in heterotopic rectus abdominis sites. Synergistic binary applications also induce the morphogenesis of rudimentary embryonic growth plates indicating that the "memory" of developmental events in embryo can be redeployed postnatally by the application of morphogen combinations. Synergistic binary applications or single relatively high doses of hTGF-β3 have shown that hTGF-β3 induces bone by expressing a variety of inductive morphogenetic proteins that result in the rapid induction of bone formation. Tissue induction thus invocated singly by hTGF-β3 recapitulates the synergistic induction of bone formation by binary applications of hTGF-β1 and -β3 isoforms with hOP-1. Both synergistic strategies result in the rapid induction and expansion of the transformed mesenchymal tissue into large corticalized heterotopic ossicles with osteoblast-like cell differentiation at the periphery of the implanted reconstituted specimens with "tissue transfiguration" in vivo. Molecularly, the rapid induction of bone formation by binary applications of hOP-1 and hTGF-β3 or by hTGF-β3 applied singly resides in the up-regulation of selected genes involved in tissue induction and morphogenesis, Osteocalcin, RUNX-2, OP-1, TGF-β1 and -β3 with however the noted lack of TGF-β2 up-regulation.

  16. Dietary protein's and dietary acid load's influence on bone health.

    PubMed

    Remer, Thomas; Krupp, Danika; Shi, Lijie

    2014-01-01

    A variety of genetic, mechano-response-related, endocrine-metabolic, and nutritional determinants impact bone health. Among the nutritional influences, protein intake and dietary acid load are two of the factors most controversially discussed. Although in the past high protein intake was often assumed to exert a primarily detrimental impact on bone mass and skeletal health, the majority of recent studies indicates the opposite and suggests a bone-anabolic influence. Studies examining the influence of alkalizing diets or alkalizing supplement provision on skeletal outcomes are less consistent, which raises doubts about the role of acid-base status in bone health. The present review critically evaluates relevant key issues such as acid-base terminology, influencing factors of intestinal calcium absorption, calcium balance, the endocrine-metabolic milieu related to metabolic acidosis, and some methodological aspects of dietary exposure and bone outcome examinations. It becomes apparent that for an adequate identification and characterization of either dietary acid load's or protein's impact on bone, the combined assessment of both nutritional influences is necessary.

  17. [Properties evaluation of collagen-hydroxyapatite-chondroitin sulfate-bone morphogenetic protein bone substitute material].

    PubMed

    Wang, Hao; Zhang, Li-cheng; Shi, Tao; Xiong, Qi; Tang, Pei-fu

    2011-10-18

    To construct a new 3D porous bone substitute material with collagen, hydroxyapatite and chondroitin sulfate, which has the main components of nature bone and the cell growth factor BMP-2 with bone inductive ability. Collagen-hydroxyapatite-chondroitin sulfate scaffolds were prepared by chemical cross linking and freeze-drying, and bone morphogenetic protein (BMP) was incorporated into the scaffolds by adsorption. The bone substitute material was investigated by HE analysis, scanning electron microscope(SEM), electron spectroscopy for chemical analysis(ESCA), and X-ray diffraction(XRD). Rat mesenchymal stem cells (MSCs) were seeded into the scaffolds and cultured to form cell/scaffold (CS) constructs in vitro. The ectopic osteoinduction of the scaffolds were evaluated in vivo. The bone substitute material had a porous 3D structure facilitating cells growing into it. Implanted into the muscle, the scaffolds were degraded with the forming of new bone. Our Findings indicate that the bone substitute material has good biocompatibility and its attachment to CS could improve the adhesion and differentiation of cells.

  18. Regulators of G protein signaling 12 promotes osteoclastogenesis in bone remodeling and pathological bone loss

    PubMed Central

    Yuan, X; Cao, J; Liu, T; Li, Y-P; Scannapieco, F; He, X; Oursler, M J; Zhang, X; Vacher, J; Li, C; Olson, D; Yang, S

    2015-01-01

    Regulators of G protein signaling (Rgs) have pivotal roles in controlling various cellular processes, such as cell differentiation. How Rgs proteins regulate osteoclast (OC) differentiation, function and bone homeostasis is poorly understood. It was previously demonstrated that Rgs12, the largest protein in the Rgs family, is predominantly expressed in OCs and regulates OC differentiation in vitro. To further understand the role and mechanism of Rgs12 in OC differentiation and bone diseases in vivo, we created OC-targeted Rgs12 knockout mice by using inducible Mx1-Cre and CD11b-Cre. Deletion of Rgs12 in hematopoietic cells or specifically in OC precursors resulted in increased bone mass with decreased OC numbers. Loss of Rgs12 impaired OC differentiation and function with impaired Ca2+ oscillations and reduced nuclear factor of activated T cells (NFAT) 2 expression. The introduction of wild-type osteoblasts did not rescue the defective osteoclastogenesis. Ectopic expression of NFAT2 rescued defective OC differentiation in CD11b;Rgs12fl/fl cells and promoted normal OC differentiation. Moreover, deletion of Rgs12 significantly inhibited pathological osteoclastogenesis and bone destruction in Rgs12-deficient mice that were subjected to ovariectomy and lipodysaccharide for bone loss. Thus our findings demonstrate that Rgs12 is an important regulator in OC differentiation and function and identify Rgs12 as a potential therapeutic target for osteoporosis and inflammation-induced bone loss. PMID:25909889

  19. Pre-Steady-State Decoding of the Bicoid Morphogen Gradient

    PubMed Central

    Bergmann, Sven; Sandler, Oded; Sberro, Hila; Shnider, Sara; Schejter, Eyal; Shilo, Ben-Zion; Barkai, Naama

    2007-01-01

    Morphogen gradients are established by the localized production and subsequent diffusion of signaling molecules. It is generally assumed that cell fates are induced only after morphogen profiles have reached their steady state. Yet, patterning processes during early development occur rapidly, and tissue patterning may precede the convergence of the gradient to its steady state. Here we consider the implications of pre-steady-state decoding of the Bicoid morphogen gradient for patterning of the anterior–posterior axis of the Drosophila embryo. Quantitative analysis of the shift in the expression domains of several Bicoid targets (gap genes) upon alteration of bcd dosage, as well as a temporal analysis of a reporter for Bicoid activity, suggest that a transient decoding mechanism is employed in this setting. We show that decoding the pre-steady-state morphogen profile can reduce patterning errors caused by fluctuations in the rate of morphogen production. This can explain the surprisingly small shifts in gap and pair-rule gene expression domains observed in response to alterations in bcd dosage. PMID:17298180

  20. Purification of water-soluble bone-inductive protein from bovine demineralized bone matrix.

    PubMed

    Yoshimura, Y; Hirano, A; Nishida, M; Kawada, J; Horisaka, Y; Okamoto, Y; Matsumoto, N; Yamashita, K; Takagi, T

    1993-05-01

    The water-soluble fraction containing bone-inductive activity was purified from guanidine-hydrochloride extracts of bovine demineralized bone. The purification steps include ultrafiltration, dialysis, affinity chromatography on heparin-Sepharose and gel chromatography on Sephacryl S-200. Combination of these steps was proven to be an effective and rapid method for the purification of this protein. Subcutaneous implantation of the water-soluble protein with type I collagen was carried out in the thorax of rats. When alkaline phosphatase activity and calcium content in implants were used as indices for purification, the water-soluble bone-inductive protein was purified > 600-fold according to the enzyme activity and 64-fold according to the calcium content. A morphological examination revealed that many chondrocyte and osteoblast cells were seen in the location of the implanted material. Sodium dodecyl sulfate/gel electrophoresis of the protein produced in this way under non-reducing conditions revealed four protein bands of 18, 16, 14 and 11 kDa. None of the separated bands had any biological activity. This result suggests that the water-soluble bone-inductive activity depends on an associated form of various proteins in the range of 18 to 11 kDa.

  1. [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

  2. High dietary protein intake and protein-related acid load on bone health

    USDA-ARS?s Scientific Manuscript database

    Protein is an essential nutrient for humans and is required for maintaining optimal bone structure and growth. Consumption of high protein diets in excess of the Recommended Dietary Allowance of (0.8 g protein/kg body weight/d) is increasingly popular due to the benefits of protein on preserving lea...

  3. Protein quality affects bone status during moderate protein restriction in growing mice.

    PubMed

    Rouy, Emilien; Vico, Laurence; Laroche, Norbert; Benoit, Valérie; Rousseau, Brigitte; Blachier, François; Tomé, Daniel; Blais, Anne

    2014-02-01

    Adequate protein intake during development is critical to ensure optimal bone gain and to attain a higher peak bone mass later on. We hypothesized that the quality of the dietary protein is of prime importance for bone physiology during moderate protein restriction. The target population was growing Balb/C mice. We compared two protein restricted diets (6% of total energy as protein), one based on soy (LP-SOY) and one based on casein (LP-CAS). For comparison, a normal protein soy-based control group (NP-SOY) and a low protein group receiving an anabolic daily parathyroid hormone (PTH) 1-34 injection (LP-SOY+PTH) were included in the protocol. After 8weeks, LP-SOY mice had reduced body weights related to a lower lean mass whereas LP-CAS mice were not different from the NP-SOY group. LP-SOY mice were characterized by lower femoral cortical thickness, bone volume, trabecular number and thickness and increased medullar adiposity when compared to both the LP-CAS and NP-SOY groups. However, the dietary intervention had no effect on the vertebral parameters. The negative effect of the LP-SOY diet was correlated to an impaired bone formation as shown by the reduced P1NP serum level as well as the reduced osteoid surfaces and bone formation rate in the femur. PTH injection in LP-SOY mice had no effect on total weight or lean mass, but improved all bone parameters at both femoral and vertebral sites, suggesting that amino acid deficiency was not the primary reason for degraded bone status in mice consuming soy protein. In conclusion, our study showed that under the same protein restriction (6% of energy), a soy diet leads to impaired bone health whereas a casein diet has little effect when compared to a normal protein control. © 2013.

  4. 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

  5. ANA deficiency enhances bone morphogenetic protein-induced ectopic bone formation via transcriptional events.

    PubMed

    Miyai, Kentaro; Yoneda, Mitsuhiro; Hasegawa, Urara; Toita, Sayaka; Izu, Yayoi; Hemmi, Hiroaki; Hayata, Tadayoshi; Ezura, Yoichi; Mizutani, Shuki; Miyazono, Kohei; Akiyoshi, Kazunari; Yamamoto, Tadashi; Noda, Masaki

    2009-04-17

    Ectopic bone formation after joint replacement or brain injury in humans is a serious complication that causes immobility of joints and severe pain. However, mechanisms underlying such ectopic bone formation are not fully understood. Bone morphogenetic protein (BMPs) are defined as inducers of ectopic bone formation, and they are regulated by several types of inhibitors. ANA is an antiproliferative molecule that belongs to Tob/BTG family, but its activity in bone metabolism has not been known. Here, we examined the role of ANA on ectopic bone formation activity of BMP. In ANA-deficient and wild-type mice, BMP2 was implanted to induce ectopic bone formation in muscle. ANA deficiency increased mass of newly formed bone in vivo compared with wild-type based on 3D-muCT analyses. ANA mRNA was expressed in bone in vivo as well as in osteoblastic cells in vitro. Such ANA mRNA levels were increased by BMP2 treatment in MC3T3-E1 osteoblastic cells. Overexpression of ANA suppressed BMP-induced expression of luciferase reporter gene linked to BMP response elements in these cells. Conversely, ANA mRNA knockdown by small interference RNA enhanced the BMP-dependent BMP response element reporter expression. It also enhanced BMP-induced osteoblastic differentiation in muscle-derived C2C12 cells. Immunoprecipitation assay indicated that ANA interacts with Smad8. Thus, ANA is a suppressor of ectopic bone formation induced by BMP, and this inhibitory ANA activity is a part of the negative feedback regulation of BMP function.

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

    PubMed

    Subramanian, Sangeeta; Mitchell, Ashley; Yu, Weiling; Snyder, Sabrina; Uhrich, Kathryn; O'Connor, J Patrick

    2015-07-01

    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.

  7. Evaluation of a novel reconstituted bone xenograft using processed bovine cancellous bone in combination with purified bovine bone morphogenetic protein.

    PubMed

    Long, Bi; Dan, Li; Jian, Liu; Yunyu, Hu; Shu, He; Zhi, Yuan

    2012-01-01

    Xenogeneic grafting represents an alternative to autogenous grafting in osseous reconstruction and exhibits many beneficial properties. However, the usefulness of xenogeneic bone relies on necessary processing procedures for removing antigens and viruses, and preserving biological activities simultaneously. By chemical treatment of bovine cancellous bone to make it an antigen-free scaffold, and extraction of bone morphogenetic protein (BMP) from bovine cortical bone, followed by recombination of the scaffold with the BMP, we developed a new grafting material, reconstituted bone xenograft (RBX). In this study, scanning electron microscope and energy dispersive X-ray were first employed to observe the structure and components of RBX. Then the biomechanical property was evaluated by applying compression in a materials testing machine. Subsequently, the immunologic evaluation was performed by measuring galactose-alpha-1,3-galactose (α-gal) epitope in vivo and proinflammatory cytokine (TNF-α) secreted by human monocytic cell line (THP-1) in vitro. Finally, this RBX was implanted into segmental radial defects in a rabbit model, and its ability to treat large bone defects was specifically evaluated. Although the compressive strength of RBX was 10% lower than that of unprocessed bovine cancellous bone (UBCB), the basic porous structure and natural components were still kept in this composite. The α-gal xenoantigen level was significantly lower in RBX (P < 0.05) compared with UBCB. Moreover, the TNF-α level was significantly (P < 0.05) reduced compared with UBCB when THP-1 was exposed to RBX. On the other hand, RBX appeared to induce cartilage formation from immature cell populations and resulted in osteogenesis through endochondral-like ossification from 4 to 12 weeks in repairing segmental bone defects. These results demonstrate that RBX, with its natural microstructure and components, certain mechanical strength and strong osteoinductivity without evoking immune

  8. Emerging Multifunctional Roles of Claudin Tight Junction Proteins in Bone

    PubMed Central

    Alshbool, Fatima. Z.

    2014-01-01

    The imbalance between bone formation and resorption during bone remodeling has been documented to be a major factor in the pathogenesis of osteoporosis. Recent evidence suggests a significant role for the tight junction proteins, Claudins (Cldns), in the regulation of bone remodeling processes. In terms of function, whereas Cldns act “canonically” as key determinants of paracellular permeability, there is considerable recent evidence to suggest that Cldns also participate in cell signaling, ie, a “noncanonical function”. To this end, Cldns have been shown to regulate cell proliferation, differentiation, and gene expression in a variety of cell types. The present review will discuss Cldns' structure, their expression profile, regulation of expression, and their canonical and non- canonical functions in general with special emphasis on bone cells. In order to shed light on the noncanonical functions of Cldns in bone, we will highlight the role of Cldn-18 in regulating bone resorption and osteoclast differentiation. Collectively, we hope to provide a framework for guiding future research on understanding how Cldns modulate osteoblast and osteoclast function and overall bone homeostasis. Such studies should provide valuable insights into the pathogenesis of osteoporosis, and may highlight Cldns as novel targets for the diagnosis and therapeutic management of osteoporosis. PMID:24758302

  9. Emerging multifunctional roles of Claudin tight junction proteins in bone.

    PubMed

    Alshbool, Fatima Z; Mohan, Subburaman

    2014-07-01

    The imbalance between bone formation and resorption during bone remodeling has been documented to be a major factor in the pathogenesis of osteoporosis. Recent evidence suggests a significant role for the tight junction proteins, Claudins (Cldns), in the regulation of bone remodeling processes. In terms of function, whereas Cldns act "canonically" as key determinants of paracellular permeability, there is considerable recent evidence to suggest that Cldns also participate in cell signaling, ie, a "noncanonical function". To this end, Cldns have been shown to regulate cell proliferation, differentiation, and gene expression in a variety of cell types. The present review will discuss Cldns' structure, their expression profile, regulation of expression, and their canonical and non- canonical functions in general with special emphasis on bone cells. In order to shed light on the noncanonical functions of Cldns in bone, we will highlight the role of Cldn-18 in regulating bone resorption and osteoclast differentiation. Collectively, we hope to provide a framework for guiding future research on understanding how Cldns modulate osteoblast and osteoclast function and overall bone homeostasis. Such studies should provide valuable insights into the pathogenesis of osteoporosis, and may highlight Cldns as novel targets for the diagnosis and therapeutic management of osteoporosis.

  10. Stromal cell-derived factor-1 potentiates bone morphogenetic protein-2 induced bone formation.

    PubMed

    Higashino, Kosaku; Viggeswarapu, Manjula; Bargouti, Maggie; Liu, Hui; Titus, Louisa; Boden, Scott D

    2011-02-01

    The mechanisms driving bone marrow stem cell mobilization are poorly understood. A recent murine study found that circulating bone marrow-derived osteoprogenitor cells (MOPCs) were recruited to the site of recombinant human bone morphogenetic protein-2 (BMP-2)-induced bone formation. Stromal cell-derived factor-1α (SDF-1α) and its cellular receptor CXCR4 have been shown to mediate the homing of stem cells to injured tissues. We hypothesized that chemokines, such as SDF-1, are also involved with mobilization of bone marrow cells. The CD45(-) fraction is a major source of MOPCs. In this report we determined that the addition of BMP-2 or SDF-1 to collagen implants increased the number of MOPCs in the peripheral blood. BMP-2-induced mobilization was blocked by CXCR4 antibody, confirming the role of SDF-1 in mobilization. We determined for the first time that addition of SDF-1 to implants containing BMP-2 enhances mobilization, homing of MOPCs to the implant, and ectopic bone formation induced by suboptimal BMP-2 doses. These results suggest that SDF-1 increases the number of osteoprogenitor cells that are mobilized from the bone marrow and then home to the implant. Thus, addition of SDF-1 to BMP-2 may improve the efficiency of BMPs in vivo, making their routine use for orthopaedic applications more affordable and available to more patients.

  11. Quantifying the Gurken Morphogen Gradient in Drosophila Oogenesis

    PubMed Central

    Goentoro, Lea A.; Reeves, Gregory T.; Kowal, Craig P.; Martinelli, Luigi; Schüpbach, Trudi; Shvartsman, Stanislav Y.

    2014-01-01

    Summary Quantitative information about the distribution of morphogens is crucial for understanding their effects on cell-fate determination, yet it is difficult to obtain through direct measurements. We have developed a parameter estimation approach for quantifying the spatial distribution of Gurken, a TGFα-like EGFR ligand that acts as a morphogen in Drosophila oogenesis. Modeling of Gurken/EGFR system shows that the shape of the Gurken gradient is controlled by a single dimensionless parameter, the Thiele modulus, which reflects the relative importance of ligand diffusion and degradation. By combining the model with genetic alterations of EGFR levels, we have estimated the value of the Thiele modulus in the wild-type egg chamber. This provides a direct characterization of the shape of the Gurken gradient and demonstrates how parameter estimation techniques can be used to quantify morphogen gradients in development. PMID:16890165

  12. Morphogen rules: design principles of gradient-mediated embryo patterning.

    PubMed

    Briscoe, James; Small, Stephen

    2015-12-01

    The Drosophila blastoderm and the vertebrate neural tube are archetypal examples of morphogen-patterned tissues that create precise spatial patterns of different cell types. In both tissues, pattern formation is dependent on molecular gradients that emanate from opposite poles. Despite distinct evolutionary origins and differences in time scales, cell biology and molecular players, both tissues exhibit striking similarities in the regulatory systems that establish gene expression patterns that foreshadow the arrangement of cell types. First, signaling gradients establish initial conditions that polarize the tissue, but there is no strict correspondence between specific morphogen thresholds and boundary positions. Second, gradients initiate transcriptional networks that integrate broadly distributed activators and localized repressors to generate patterns of gene expression. Third, the correct positioning of boundaries depends on the temporal and spatial dynamics of the transcriptional networks. These similarities reveal design principles that are likely to be broadly applicable to morphogen-patterned tissues.

  13. Morphogen rules: design principles of gradient-mediated embryo patterning

    PubMed Central

    Briscoe, James; Small, Stephen

    2015-01-01

    The Drosophila blastoderm and the vertebrate neural tube are archetypal examples of morphogen-patterned tissues that create precise spatial patterns of different cell types. In both tissues, pattern formation is dependent on molecular gradients that emanate from opposite poles. Despite distinct evolutionary origins and differences in time scales, cell biology and molecular players, both tissues exhibit striking similarities in the regulatory systems that establish gene expression patterns that foreshadow the arrangement of cell types. First, signaling gradients establish initial conditions that polarize the tissue, but there is no strict correspondence between specific morphogen thresholds and boundary positions. Second, gradients initiate transcriptional networks that integrate broadly distributed activators and localized repressors to generate patterns of gene expression. Third, the correct positioning of boundaries depends on the temporal and spatial dynamics of the transcriptional networks. These similarities reveal design principles that are likely to be broadly applicable to morphogen-patterned tissues. PMID:26628090

  14. 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.

  15. Enhanced release of bone morphogenetic proteins from demineralized bone matrix by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Sung, Nak-Yun; Choi, Jong-il

    2015-06-01

    Gamma irradiation is a useful method for sterilizing demineralized bone matrix (DBM), but its effect on the osteoinductivity of DBM is still controversial. In this study, the osteoinductive activity of gamma-irradiated DBM was examined using a mouse myoblastic cell line (C2C12). DBM was extracted from adult bovine bone and was irradiated at a dose of 25 kGy using a 60cobalt gamma-irradiator. Cell proliferation with DBM was not affected by gamma-irradiation, but alkaline phosphatase and osteocalcin productions were significantly increased in C2C12 cell groups treated with gamma-irradiated DBM. It was reasoned that bone morphogenetic proteins were more efficiently released from gamma-irradiated DBM than from the non-irradiated control. This result suggests the effectiveness of radiation sterilization of bone implants

  16. Irradiated human chondrocytes expressing bone morphogenetic protein 2 promote healing of osteoporotic bone fracture in rats.

    PubMed

    Yi, Youngsuk; Choi, Kyoung Baek; Lim, Chae-Lyul; Hyun, Jong-Pil; Lee, Hyeon-Youl; Lee, Kun Bok; Yun, Lillian; Ayverdi, Asli; Hwang, Sally; Yip, Vivian; Noh, Moon Jong; Lee, Kwan Hee

    2009-10-01

    Bone morphogenetic protein 2 (BMP2) was selected as a transgene to regenerate osteoporotic bone defects after several BMPs were tested using a bone formation study in nude mice. Human chondrocytes were transduced with a BMP2-containing retroviral vector, and single clones were selected. The cells were characterized over numerous passages for growth and BMP2 expression. The single clones were irradiated and tested for viability. BMP2 expression lasted for 3 weeks before dying off completely after approximately 1 month. Irradiated and non-irradiated transduced chondrocytes successfully healed fractures in osteoporotic rats induced by ovariectomy. The osteoinducing effect of irradiated cells was better than that of their non-irradiated counterparts or a chondrocytes-only control. This study showed that delivering BMP2 from the transduced and irradiated chondrocytes could be an effective and safe method of repairing osteoporotic bone fractures.

  17. Tooth-derived bone graft material

    PubMed Central

    Kim, Young-Kyun; Lee, Junho; Kim, Kyung-Wook; Murata, Masaru; Akazawa, Toshiyuki; Mitsugi, Masaharu

    2013-01-01

    With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth. PMID:24471027

  18. Expression of bone morphogenetic proteins and cartilage-derived morphogenetic proteins during osteophyte formation in humans

    PubMed Central

    Zoricic, Sanja; Maric, Ivana; Bobinac, Dragica; Vukicevic, Slobodan

    2003-01-01

    Bone- and cartilage-derived morphogenetic proteins (BMPs and CDMPs), which are TGFβ superfamily members, are growth and differentiation factors that have been recently isolated, cloned and biologically characterized. They are important regulators of key events in the processes of bone formation during embryogenesis, postnatal growth, remodelling and regeneration of the skeleton. In the present study, we used immunohistochemical methods to investigate the distribution of BMP-2, -3, -5, -6, -7 and CDMP-1, -2, -3 in human osteophytes (abnormal bony outgrowths) isolated from osteoarthritic hip and knee joints from patients undergoing total joint replacement surgery. All osteophytes consisted of three different areas of active bone formation: (1) endochondral bone formation within cartilage residues; (2) intramembranous bone formation within the fibrous tissue cover and (3) bone formation within bone marrow spaces. The immunohistochemistry of certain BMPs and CDMPs in each of these three different bone formation sites was determined. The results indicate that each BMP has a distinct pattern of distribution. Immunoreactivity for BMP-2 was observed in fibrous tissue matrix as well as in osteoblasts; BMP-3 was mainly present in osteoblasts; BMP-6 was restricted to young osteocytes and bone matrix; BMP-7 was observed in hypertrophic chondrocytes, osteoblasts and young osteocytes of both endochondral and intramembranous bone formation sites. CDMP-1, -2 and -3 were strongly expressed in all cartilage cells. Surprisingly, BMP-3 and -6 were found in osteoclasts at the sites of bone resorption. Since a similar distribution pattern of bone morphogenetic proteins was observed during embryonal bone development, it is suggested that osteophyte formation is regulated by the same molecular mechanism as normal bone during embryogenesis. PMID:12713267

  19. Pulsed Electromagnetic Fields Enhance Bone Morphogenetic Protein-2 Dependent-Bone Regeneration.

    PubMed

    Yang, Hoon Joo; Kim, Ri Youn; Hwang, Soon Jung

    2015-10-01

    The use of recombinant human bone morphogenetic protein-2 (rhBMP-2) for the purpose of promoting bone regeneration is emerging; however, the high dose of rhBMP-2 required in humans is accompanied by several limitations, including bone resorption and swelling. To reduce the dose of rhBMP-2 required, the applicability of pulsed electromagnetic fields (PEMF) was evaluated using a rat calvarial defect model. After creating an 8-mm-diameter calvarial bone defect, a collagen sponge soaked in different concentrations (0, 2.5, 5, 10 μg) of rhBMP-2 was implanted at the defect area. One week after surgery, PEMF was applied for 8 h/day over 5 days in an experimental group of animals (n = 28) using a width of 12 μs, a pulse frequency of 60 Hz, and a magnetic intensity of 10 G. Animals were sacrificed 4 weeks after surgery and assessed by microcomputed tomography and histological and immunohistochemical analyses. In the absence of application of PEMF, bone volume, bone mineral density, trabecular thickness, trabecular number, and trabecular separation, all showed statistically significant differences, depending on the concentration of rhBMP-2 utilized (p < 0.001). PEMF accelerated bone regeneration in the groups that received 0, 2.5, and 5 μg rhBMP-2 (p < 0.05). In contrast, administration of 10 μg rhBMP-2 resulted in no additive effect on bone regeneration in combination with PEMF. Groups receiving no rhBMP-2 showed distinct bone regeneration in the central zone of the bone defect when treated with PEMF, whereas they failed to bridge the defect space without PEMF. Among the groups without PEMF, soft tissue infiltrations from the outer surface on the skin side were common. Among groups with PEMF, the groups receiving 5 and 10 μg rhBMP-2 displayed denser bone with significantly reduced dead spaces. The application of PEMF did not result in an accelerated effect on bone regeneration in groups treated with 10 μg rhBMP-2. Therefore, our data

  20. 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.

  1. Generation and interpretation of FGF morphogen gradients in vertebrates.

    PubMed

    Bökel, Christian; Brand, Michael

    2013-08-01

    Signalling via fibroblast growth factors (FGFs) is involved in multiple aspects of vertebrate development. In several instances FGFs act as morphogens, that is secreted signalling molecules that encode positional information in their graded distribution throughout their target tissue. In recent years, work in the zebrafish model system has been instrumental in addressing the cell biological basis of FGF morphogen gradient formation and interpretation. These experiments have benefitted from the optical properties of the zebrafish embryo that render this vertebrate organism particularly suited for advanced microscopic and biophysical approaches. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Primary Cilia and Intraflagellar Transport Proteins in Bone and Cartilage.

    PubMed

    Yuan, X; Yang, S

    2016-11-01

    Primary cilia, present on most mammalian cells, function as a sensor to sense the environment change and transduce signaling. Loss of primary cilia causes a group of human pleiotropic syndromes called Ciliopathies. Some of the ciliopathies display skeletal dysplasias, implying the important role of primary cilia in skeletal development and homeostasis. Emerging evidence has shown that loss or malfunction of primary cilia or ciliary proteins in bone and cartilage is associated with developmental and function defects. Intraflagellar transport (IFT) proteins are essential for cilia formation and/or function. In this review, we discuss the role of primary cilia and IFT proteins in the development of bone and cartilage, as well as the differentiation and mechanotransduction of mesenchymal stem cells, osteoblasts, osteocytes, and chondrocytes. We also include the role of primary cilia in tooth development and highlight the current advance of primary cilia and IFT proteins in the pathogenesis of cartilage diseases, including osteoarthritis, osteosarcoma, and chondrosarcoma.

  3. Physical distribution and characteristics of meat & bone meal protein

    USDA-ARS?s Scientific Manuscript database

    Meat & bone meal (MBM) is a high-protein commodity produced by the rendering of fat from unmarketable animal tissue. Concerns related to bovine spongiform encephalopathy have progressively restricted MBM’s conventional use as a feed ingredient. Consequently, significant attention has focused on th...

  4. Acute epidural lipedema: a novel entity and potential complication of bone morphogenetic protein use in lumbar spine fusion.

    PubMed

    Merrick, Michael T; Hamilton, Kendall D; Russo, Scott S

    2013-10-01

    Bone morphogenetic proteins (BMPs) induce osteogenesis, making them useful for decreasing time to union and increasing union rates. Although the advantages of BMP-2 as a substitute for iliac crest graft have been elucidated, less is known about the safety profile and adverse events linked to their use in spinal fusion. An accumulation of reactive edema in the epidural fat may lead to neural compression and significant morbidity after lumbar spinal fusion. Bone morphogenetic protein has never been implicated as a cause of spinal epidural lipedema. We report on a case of rapid accumulation of edematous adipose tissue in the epidural space after lumbar spine decompression and fusion with bone morphogenic protein. Case report. The patient was a 45-year-old woman with chronic back pain, worsening bilateral L5 radiculopathy, and degenerative disc disease. Surgery consisting of a one-level transpedicular decompression, transforaminal lumbar interbody fusion, and posterolateral fusion was performed using BMP-2 as an adjunct for arthrodesis. Two days postoperatively, the patient developed progressive cauda equina syndrome. Lumbar magnetic resonance imaging revealed edematous epidural fat extending above the initial laminectomy, compromising the spinal canal, and compressing the thecal sac. Emergent laminectomies at L3, L4, and L5 were performed, and intraoperative pathology revealed edematous epidural adipose tissue. The patient's cauda equina syndrome resolved after spinal decompression and the removal of epidural fat. Final cultures were negative for infection, and histology report yielded an accumulation of edematous fibroadipose tissue. We present a case of rapid accumulation of edematous adipose tissue causing cauda equina syndrome after a lumbar decompression and fusion surgery. The acute nature and extensive development of the lipedema presented in this case indicate an intense inflammatory reaction. We hypothesize that there may be a link between the use of BMP-2

  5. Med19 promotes bone metastasis and invasiveness of bladder urothelial carcinoma via bone morphogenetic protein 2.

    PubMed

    Wen, Hui; Feng, Chen-chen; Ding, Guan-xiong; Meng, Dong-liang; Ding, Qiang; Fang, Zu-jun; Xia, Guo-wei; Xu, Gang; Jiang, Hao-wen

    2013-06-01

    Bladder cancer (BCa) remained a major health problem. Med19 was related to tumor growth of BCa. Bone morphogenetic proteins (BMPs) were reported to be critical in bone metastasis of cancer. We therefore investigated the relations between Med19 and BMPs in BCa and their effect on bone metastasis of BCa. Bladder cancer cell lines were cultured and interfered with Med19 shRNA and control. Expressions of BMP-1, BMP-2, BMP-4, BMP-5, BMP-6, BMP-7, BMP-9, and BMP-15 were studied between 2 groups. Fifty-two BCa samples were included for immunohistochemical staining of Med19 and BMP-2. Expressions were scored and studied statistically. Invasiveness was studied with Transwell assay. Silencing or Med19 in BCa cells induced altered expressions of BMPs. Increased expressions of BMP-1, BMP-4, BMP-6, BMP-7, and BMP-15 and decreased expressions of BMP-2, BMP-5, and BMP-9 were noticed, but only BMP-2 reached statistical significance. Expressions of Med19 and BMP-2 were significantly higher in cases with bone metastasis and were positively correlated in cases with bone metastasis and muscle invasion. Med19 is a critical factor involved in the invasiveness and promotion of bone metastasis of BCa, possibly via BMP-2.

  6. A comprehensive clinical review of recombinant human bone morphogenetic protein-2 (INFUSE® Bone Graft)

    PubMed Central

    Peckham, Steven M.; Badura, Jeffrey M.

    2007-01-01

    The combination of recombinant human bone morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS) carrier has been shown to induce bone formation in a number of preclinical and clinical investigations. In 2002, rhBMP-2/ACS at a 1.5-mg/cc concentration (INFUSE® Bone Graft, Medtronic Spinal and Biologics, Memphis, TN) was FDA-approved as an autograft replacement for certain interbody spinal fusion procedures. In 2004, INFUSE® Bone Graft was approved for open tibial fractures with an intermedullary (IM) nail fixation. Most recently, in March 2007, INFUSE® Bone Graft was approved as an alternative to autogenous bone grafts for sinus augmentations, and for localised alveolar ridge augmentations for defects associated with extraction sockets. The culmination of extensive preclinical and clinical research and three FDA approvals makes rhBMP-2 one of the most studied, published and significant advances in orthopaedics. This review article summarises a number of clinical findings of rhBMP-2/ACS, including the FDA-approved investigational device exemption (IDE) studies used in gaining the aforementioned approvals. PMID:17639384

  7. Effect of the “protein diet” and bone tissue.

    PubMed

    Nascimento da Silva, Zoraide; Azevedo de Jesuz, Vanessa; De Salvo Castro, Eduardo; Soares da Costa, Carlos Alberto; Teles Boaventura, Gilson; Blondet de Azeredo, Vilma

    2014-01-01

    The aim of this study is to evaluate the effect of the hyperproteic diet consumption on bone tissue. The study was conducted during sixty days. Twenty eight Wistar albinus rats, adults, originated from Laboratory of Experimental Nutrition were divided in four groups: (n = 7); Control 1 (C1), Control 2 (C2), Hyperproteic 1 (HP1) e Hyperproteic 2 (HP2). The C2 and HP2 groups were submitted to 30% of food restriction. The hyperproteic diet was based on the Atkins diet and prepared to simulate the protein diet. At the end of the study the animals were anesthetized to performer bone densitometry analyses by DEXA and blood and tissue collection. Serum and bone minerals analyses were conducted by colorimetric methods in automated equipment. The total bone mineral density (BMD) of the pelvis and the spine of the food restriction groups (HP2 e C2) were lower (p < 0.05) than C1 e HP1 groups. While the femur BMD of the HP2 was lower (p < 0.05) related to others groups. It had been observed reduction (p < 0.05) in the medium point of the width of femur diaphysis and in bone calcium level in the hyperproteic groups (HP1 e HP2). It was observed similar effect on the osteocalcin level, that presented lower (p < 0.05) in the hyperproteic groups. The insulin level was lower only in HP2 and serum calcium of the HP1 and HP2 groups was lower than C1. The protein diet promotes significant bone change on femur and in the hormones levels related to bone synthesis and maintenance of this tissue.

  8. Visualisation and Quantification of Morphogen Gradient Formation in the Zebrafish

    PubMed Central

    Harvey, Steven A; Smith, James C

    2009-01-01

    During embryonic development, signalling molecules known as morphogens act in a concentration-dependent manner to provide positional information to responding tissues. In the early zebrafish embryo, graded signalling by members of the nodal family induces the formation of mesoderm and endoderm, thereby patterning the embryo into three germ layers. Nodal signalling has also been implicated in the establishment of the dorso-ventral axis of the embryo. Although one can infer the existence of nodal gradients by comparing gene expression patterns in wild-type embryos and embryos in which nodal signalling is diminished or augmented, real understanding can only come from directly observing the gradients. One approach is to determine local ligand concentrations in the embryo, but this is technically challenging, and the presence of inhibitors might cause the effective concentration of a ligand to differ from its actual concentration. We have therefore taken two approaches to visualise a direct response to nodal signalling. In the first, we have used transgenic embryos to study the nuclear accumulation of a Smad2-Venus fusion protein, and in the second we have used bimolecular fluorescence complementation to visualise the formation of a complex between Smad2 and Smad4. This has allowed us to visualise, in living embryos, the formation of a graded distribution of nodal signalling activity. We have quantified the formation of the gradient in time and space, and our results not only confirm that nodal signalling patterns the embryo into three germ layers, but also shed light on its role in patterning the dorso-ventral axis and highlight unexpected complexities of mesodermal patterning. PMID:19419239

  9. [Human bone morphogenetic protein-2: recombinant expression in E. coli].

    PubMed

    Ma, Q; Dang, G; Ma, D

    1998-04-01

    To explore the way of producing human bone morphogenetic protein-2(hBMP-2) for bone healing by using the gene engeneering techniques. hBMP-2 cDNA fragment, which consists of 3' end partial propeptide and mature peptide sequence, was inserted into the multiple cloning site of expression vector pkpL-3a via ligation. The recombinant plasmid pkpL-3a/hBMP-2 was transformed into E. coli pOp2136. By the method of restriction map, the positive expression clone was selected. SDS-PAGE analysis showed a new foreign protein band near 27,000 after induction. The yield of induced hBMP-2 accouned for 10% of the total bacterial proteins. The partial purified recombinant hBMP-2 was implanted into Wistar rat thigh. After 4 weeks, histological analysis showed that it induced the proliferation of mesenchymal type cells and formation of new cartilage and bone in the implantation area. The hBMP-2 produced by gene engeneering techniques has the biologic capacity of ectopic bone formation.

  10. Morphogengineering roots: comparing mechanisms of morphogen gradient formation

    PubMed Central

    2012-01-01

    Background In developmental biology, there has been a recent focus on the robustness of morphogen gradients as possible providers of positional information. It was shown that functional morphogen gradients present strong biophysical constraints and lack of robustness to noise. Here we explore how the details of the mechanism which underlies the generation of a morphogen gradient can influence those properties. Results We contrast three gradient-generating mechanisms, (i) a source-decay mechanism; and (ii) a unidirectional transport mechanism; and (iii) a so-called reflux-loop mechanism. Focusing on the dynamics of the phytohormone auxin in the root, we show that only the reflux-loop mechanism can generate a gradient that would be adequate to supply functional positional information for the Arabidopsis root, for biophysically reasonable kinetic parameters. Conclusions We argue that traits that differ in spatial and temporal time-scales can impose complex selective pressures on the mechanism of morphogen gradient formation used for the development of the particular organism. PMID:22583698

  11. Development of morphogen gradient: The role of dimension and discreteness

    SciTech Connect

    Teimouri, Hamid; Kolomeisky, Anatoly B.

    2014-02-28

    The fundamental processes of biological development are governed by multiple signaling molecules that create non-uniform concentration profiles known as morphogen gradients. It is widely believed that the establishment of morphogen gradients is a result of complex processes that involve diffusion and degradation of locally produced signaling molecules. We developed a multi-dimensional discrete-state stochastic approach for investigating the corresponding reaction-diffusion models. It provided a full analytical description for stationary profiles and for important dynamic properties such as local accumulation times, variances, and mean first-passage times. The role of discreteness in developing of morphogen gradients is analyzed by comparing with available continuum descriptions. It is found that the continuum models prediction about multiple time scales near the source region in two-dimensional and three-dimensional systems is not supported in our analysis. Using ideas that view the degradation process as an effective potential, the effect of dimensionality on establishment of morphogen gradients is also discussed. In addition, we investigated how these reaction-diffusion processes are modified with changing the size of the source region.

  12. Whey Protein Concentrate Hydrolysate Prevents Bone Loss in Ovariectomized Rats.

    PubMed

    Kim, Jonggun; Kim, Hyung Kwan; Kim, Saehun; Imm, Ji-Young; Whang, Kwang-Youn

    2015-12-01

    Milk is known as a safe food and contains easily absorbable minerals and proteins, including whey protein, which has demonstrated antiosteoporotic effects on ovariectomized rats. This study evaluated the antiosteoporotic effect of whey protein concentrate hydrolysate (WPCH) digested with fungal protease and whey protein concentrate (WPC). Two experiments were conducted to determine (1) efficacy of WPCH and WPC and (2) dose-dependent impact of WPCH in ovariectomized rats (10 weeks old). In Experiment I, ovariectomized rats (n=45) were allotted into three dietary treatments of 10 g/kg diet of WPC, 10 g/kg diet of WPCH, and a control diet. In Experiment II, ovariectomized rats (n=60) were fed four different diets (0, 10, 20, and 40 g/kg of WPCH). In both experiments, sham-operated rats (n=15) were also fed a control diet containing the same amount of amino acids and minerals as dietary treatments. After 6 weeks, dietary WPCH prevented loss of bone, physical properties, mineral density, and mineral content, and improved breaking strength of femurs, with similar effect to WPC. The bone resorption enzyme activity (tartrate resistance acid phosphatase) in tibia epiphysis decreased in response to WPCH supplementation, while bone formation enzyme activity (alkaline phosphatase) was unaffected by ovariectomy and dietary treatment. Bone properties and strength increased as the dietary WPCH level increased (10 and 20 g/kg), but there was no difference between the 20 and 40 g/kg treatment. WPCH and WPC supplementation ameliorated bone loss induced by ovariectomy in rats.

  13. Whey Protein Concentrate Hydrolysate Prevents Bone Loss in Ovariectomized Rats

    PubMed Central

    Kim, Jonggun; Kim, Hyung Kwan; Kim, Saehun; Imm, Ji-Young

    2015-01-01

    Abstract Milk is known as a safe food and contains easily absorbable minerals and proteins, including whey protein, which has demonstrated antiosteoporotic effects on ovariectomized rats. This study evaluated the antiosteoporotic effect of whey protein concentrate hydrolysate (WPCH) digested with fungal protease and whey protein concentrate (WPC). Two experiments were conducted to determine (1) efficacy of WPCH and WPC and (2) dose-dependent impact of WPCH in ovariectomized rats (10 weeks old). In Experiment I, ovariectomized rats (n=45) were allotted into three dietary treatments of 10 g/kg diet of WPC, 10 g/kg diet of WPCH, and a control diet. In Experiment II, ovariectomized rats (n=60) were fed four different diets (0, 10, 20, and 40 g/kg of WPCH). In both experiments, sham-operated rats (n=15) were also fed a control diet containing the same amount of amino acids and minerals as dietary treatments. After 6 weeks, dietary WPCH prevented loss of bone, physical properties, mineral density, and mineral content, and improved breaking strength of femurs, with similar effect to WPC. The bone resorption enzyme activity (tartrate resistance acid phosphatase) in tibia epiphysis decreased in response to WPCH supplementation, while bone formation enzyme activity (alkaline phosphatase) was unaffected by ovariectomy and dietary treatment. Bone properties and strength increased as the dietary WPCH level increased (10 and 20 g/kg), but there was no difference between the 20 and 40 g/kg treatment. WPCH and WPC supplementation ameliorated bone loss induced by ovariectomy in rats. PMID:26367331

  14. Rank Protein Immunolabeling during Bone-Implant Interface Healing Process

    PubMed Central

    Ávila Souza, Francisley; Pereira Queiroz, Thallita; Rodrigues Luvizuto, Eloá; Nishioka, Renato Sussumu; Garcia-JR, Idelmo Rangel; de Carvalho, Paulo Sérgio Perri; Okamoto, Roberta

    2010-01-01

    The purpose of this paper was to evaluate the expression of RANK protein during bone-healing process around machined surface implants. Twenty male Wistar rats, 90 days old, after having had a 2 mm diameter and 6 mm long implant inserted in their right tibias, were evaluated at 7, 14, 21, and 42 days after healing. After obtaining the histological samples, slides were subjected to RANK immunostaining reaction. Results were quantitatively evaluated. Results. Immunolabeling analysis showed expressions of RANK in osteoclast and osteoblast lineage cells. The statistical analysis showed an increase in the expression of RANK in osteoblasts at 7 postoperative days and a gradual decrease during the chronology of the healing process demonstrated by mild cellular activity in the final stage (P < .05). Conclusion. RANK immunolabeling was observed especially in osteoclast and osteoblast cells in primary bone during the initial periods of bone-healing/implant interface. PMID:20706673

  15. Expression of CD31, Met/hepatocyte growth factor receptor and bone morphogenetic protein in bone metastasis of osteosarcoma.

    PubMed

    Arihiro, K; Inai, K

    2001-02-01

    The mechanism of metastasis of osteosarcoma cells to other bones has not yet fully been clarified. The purpose of the present study was to examine whether various factors involve the formation of osteosarcoma metastatic foci in other bones. Immunohistochemically, CD31 expression in osteosarcoma with no bone metastasis and osteosarcoma with bone metastasis was noted in 10 and 75% of cases, respectively. Met/hepatocyte growth factor (HGF) receptor expression in osteosarcoma with no bone metastasis and osteosarcoma with bone metastasis was noted in 90 and 25% of cases, respectively. Bone morphogenetic protein (BMP) expression in osteosarcoma with no bone metastasis and osteosarcoma with bone metastasis was noted in 20 and 75% of cases, respectively. Metastasis of osteosarcoma cells to other bones was significantly correlated with expression of BMP and CD31 and with no expression of Met/HGF receptor protein in osteosarcoma cells. In contrast, expression of insulin-like growth factor receptor in osteosarcoma cells did not correlate significantly with bone metastasis. These results suggest that formation of metastatic foci of osteosarcoma cells in other bones is regulated by CD31, which is associated with migration between endothelial cells, by BMP, which can induce and activate various mesenchymal cells affecting bone formation, and by escape of effect by HGF, which promotes differentiation of osteosarcoma cells.

  16. Human Cementum Protein 1 induces expression of bone and cementum proteins by human gingival fibroblasts.

    PubMed

    Carmona-Rodríguez, Bruno; Alvarez-Pérez, Marco Antonio; Narayanan, A Sampath; Zeichner-David, Margarita; Reyes-Gasga, José; Molina-Guarneros, Juan; García-Hernández, Ana Lilia; Suárez-Franco, José Luis; Chavarría, Ivet Gil; Villarreal-Ramírez, Eduardo; Arzate, Higinio

    2007-07-06

    We recently presented evidence showing that a human cementoblastoma-derived protein, named Cementum Protein 1 (CEMP1) may play a role as a local regulator of cementoblast differentiation and cementum-matrix mineralization. This protein was shown to be expressed by cementoblasts and progenitor cells localized in the periodontal ligament. In this study we demonstrate that transfection of CEMP1 into human gingival fibroblasts (HGF) induces mineralization and expression of bone and cementum-matrix proteins. The transfected HGF cells had higher alkaline phosphatase activity and proliferation rate and they expressed genes for alkaline phosphatase, bone sialoprotein, osteocalcin, osteopontin, the transcription factor Runx2/Cbfa1, and cementum attachment protein (CAP). They also produced biological-type hydroxyapatite. These findings indicate that the CEMP1 might participate in differentiation and mineralization of nonosteogenic cells, and that it might have a potential function in cementum and bone formation.

  17. Human Cementum Protein 1 induces expression of bone and cementum proteins by human gingival fibroblasts

    SciTech Connect

    Carmona-Rodriguez, Bruno; Alvarez-Perez, Marco Antonio; Narayanan, A. Sampath; Zeichner-David, Margarita; Reyes-Gasga, Jose; Molina-Guarneros, Juan; Garcia-Hernandez, Ana Lilia; Suarez-Franco, Jose Luis; Chavarria, Ivet Gil; Villarreal-Ramirez, Eduardo; Arzate, Higinio . E-mail: harzate@servidor.unam.mx

    2007-07-06

    We recently presented evidence showing that a human cementoblastoma-derived protein, named Cementum Protein 1 (CEMP1) may play a role as a local regulator of cementoblast differentiation and cementum-matrix mineralization. This protein was shown to be expressed by cementoblasts and progenitor cells localized in the periodontal ligament. In this study we demonstrate that transfection of CEMP1 into human gingival fibroblasts (HGF) induces mineralization and expression of bone and cementum-matrix proteins. The transfected HGF cells had higher alkaline phosphatase activity and proliferation rate and they expressed genes for alkaline phosphatase, bone sialoprotein, osteocalcin, osteopontin, the transcription factor Runx2/Cbfa1, and cementum attachment protein (CAP). They also produced biological-type hydroxyapatite. These findings indicate that the CEMP1 might participate in differentiation and mineralization of nonosteogenic cells, and that it might have a potential function in cementum and bone formation.

  18. Multi-protein Delivery by Nanodiamonds Promotes Bone Formation

    PubMed Central

    Moore, L.; Gatica, M.; Kim, H.; Osawa, E.; Ho, D.

    2013-01-01

    Bone morphogenetic proteins (BMPs) are well-studied regulators of cartilage and bone development that have been Food and Drug Administration (FDA)-approved for the promotion of bone formation in certain procedures. BMPs are seeing more use in oral and maxillofacial surgeries because of recent FDA approval of InFUSE® for sinus augmentation and localized alveolar ridge augmentation. However, the utility of BMPs in medical and dental applications is limited by the delivery method. Currently, BMPs are delivered to the surgical site by the implantation of bulky collagen sponges. Here we evaluate the potential of detonation nanodiamonds (NDs) as a delivery vehicle for BMP-2 and basic fibroblast growth factor (bFGF). Nanodiamonds are biocompatible, 4- to 5-nm carbon nanoparticles that have previously been used to deliver a wide variety of molecules, including proteins and peptides. We find that both BMP-2 and bFGF are readily loaded onto NDs by physisorption, forming a stable colloidal solution, and are triggered to release in slightly acidic conditions. Simultaneous delivery of BMP-2 and bFGF by ND induces differentiation and proliferation in osteoblast progenitor cells. Overall, we find that NDs provide an effective injectable alternative for the delivery of BMP-2 and bFGF to promote bone formation. PMID:24045646

  19. Multi-protein delivery by nanodiamonds promotes bone formation.

    PubMed

    Moore, L; Gatica, M; Kim, H; Osawa, E; Ho, D

    2013-11-01

    Bone morphogenetic proteins (BMPs) are well-studied regulators of cartilage and bone development that have been Food and Drug Administration (FDA)-approved for the promotion of bone formation in certain procedures. BMPs are seeing more use in oral and maxillofacial surgeries because of recent FDA approval of InFUSE(®) for sinus augmentation and localized alveolar ridge augmentation. However, the utility of BMPs in medical and dental applications is limited by the delivery method. Currently, BMPs are delivered to the surgical site by the implantation of bulky collagen sponges. Here we evaluate the potential of detonation nanodiamonds (NDs) as a delivery vehicle for BMP-2 and basic fibroblast growth factor (bFGF). Nanodiamonds are biocompatible, 4- to 5-nm carbon nanoparticles that have previously been used to deliver a wide variety of molecules, including proteins and peptides. We find that both BMP-2 and bFGF are readily loaded onto NDs by physisorption, forming a stable colloidal solution, and are triggered to release in slightly acidic conditions. Simultaneous delivery of BMP-2 and bFGF by ND induces differentiation and proliferation in osteoblast progenitor cells. Overall, we find that NDs provide an effective injectable alternative for the delivery of BMP-2 and bFGF to promote bone formation.

  20. Calcium Sulfate with Stearic Acid as an Encouraging Carrier for Reindeer Bone Protein Extract

    PubMed Central

    Tölli, Hanna; Birr, Elli; Sandström, Kenneth; Jämsä, Timo; Jalovaara, Pekka

    2011-01-01

    Various bone proteins and growth factors in specific concentrations are required for bone formation. If the body cannot produce sufficient quantities of these factors, bone trauma can be healed with an implant that includes the required factors in a carrier. This study was designed to evaluate various calcium salt candidates that can be used as carrier with reindeer bone protein extract to induce ectopic bone formation in the muscle pouch model of mouse. The bone protein extract was either impregnated into the disc form of carrier or mixed with carrier powder before implantation. The radiographic analysis indicated increased bone formation in all of the active groups containing the bone protein extract compared to the controls within 21 days follow-up. The highest bone formation was seen in the group with calcium sulfate with stearic acid where new bone and calcified cartilage were clearly visible. The greatest bone formation occurred in the groups that had bone protein extract readily available. This indicates that the bone forming factors in sufficient concentrations are required at the early stage of bone formation. The calcium sulfate with stearic acid was the most suitable and effective carrier for reindeer bone protein extract. PMID:28824145

  1. Bone protein "extractomics": comparing the efficiency of bone protein extractions of Gallus gallus in tandem mass spectrometry, with an eye towards paleoproteomics.

    PubMed

    Schroeter, Elena R; DeHart, Caroline J; Schweitzer, Mary H; Thomas, Paul M; Kelleher, Neil L

    2016-01-01

    Proteomic studies of bone require specialized extraction protocols to demineralize and solubilize proteins from within the bone matrix. Although various protocols exist for bone protein recovery, little is known about how discrete steps in each protocol affect the subset of the bone proteome recovered by mass spectrometry (MS) analyses. Characterizing these different "extractomes" will provide critical data for development of novel and more efficient protein extraction methodologies for fossils. Here, we analyze 22 unique sub-extractions of chicken bone and directly compare individual extraction components for their total protein yield and diversity and coverage of bone proteins identified by MS. We extracted proteins using different combinations and ratios of demineralizing reagents, protein-solubilizing reagents, and post-extraction buffer removal methods, then evaluated tryptic digests from 20 µg aliquots of each fraction by tandem MS/MS on a 12T FT-ICR mass spectrometer. We compared total numbers of peptide spectral matches, peptides, and proteins identified from each fraction, the redundancy of protein identifications between discrete steps of extraction methods, and the sequence coverage obtained for select, abundant proteins. Although both alpha chains of collagen I (the most abundant protein in bone) were found in all fractions, other collagenous and non-collagenous proteins (e.g., apolipoprotein, osteonectin, hemoglobin) were differentially identified. We found that when a standardized amount of extracted proteins was analyzed, extraction steps that yielded the most protein (by weight) from bone were often not the ones that produced the greatest diversity of bone proteins, or the highest degree of protein coverage. Generally, the highest degrees of diversity and coverage were obtained from demineralization fractions, and the proteins found in the subsequent solubilization fractions were highly redundant with those in the previous fraction. Based on these

  2. Bone protein “extractomics”: comparing the efficiency of bone protein extractions of Gallus gallus in tandem mass spectrometry, with an eye towards paleoproteomics

    PubMed Central

    DeHart, Caroline J.; Schweitzer, Mary H.; Thomas, Paul M.; Kelleher, Neil L.

    2016-01-01

    Proteomic studies of bone require specialized extraction protocols to demineralize and solubilize proteins from within the bone matrix. Although various protocols exist for bone protein recovery, little is known about how discrete steps in each protocol affect the subset of the bone proteome recovered by mass spectrometry (MS) analyses. Characterizing these different “extractomes” will provide critical data for development of novel and more efficient protein extraction methodologies for fossils. Here, we analyze 22 unique sub-extractions of chicken bone and directly compare individual extraction components for their total protein yield and diversity and coverage of bone proteins identified by MS. We extracted proteins using different combinations and ratios of demineralizing reagents, protein-solubilizing reagents, and post-extraction buffer removal methods, then evaluated tryptic digests from 20 µg aliquots of each fraction by tandem MS/MS on a 12T FT-ICR mass spectrometer. We compared total numbers of peptide spectral matches, peptides, and proteins identified from each fraction, the redundancy of protein identifications between discrete steps of extraction methods, and the sequence coverage obtained for select, abundant proteins. Although both alpha chains of collagen I (the most abundant protein in bone) were found in all fractions, other collagenous and non-collagenous proteins (e.g., apolipoprotein, osteonectin, hemoglobin) were differentially identified. We found that when a standardized amount of extracted proteins was analyzed, extraction steps that yielded the most protein (by weight) from bone were often not the ones that produced the greatest diversity of bone proteins, or the highest degree of protein coverage. Generally, the highest degrees of diversity and coverage were obtained from demineralization fractions, and the proteins found in the subsequent solubilization fractions were highly redundant with those in the previous fraction. Based on

  3. ROBUSTNESS OF MORPHOGEN GRADIENTS WITH "BUCKET BRIGADE" TRANSPORT THROUGH MEMBRANE-ASSOCIATED NON-RECEPTORS.

    PubMed

    Lei, Jinzhi; Wang, Dongyong; Song, You; Nie, Qing; Wan, Frederic Y M

    2013-05-01

    Robust multiple-fate morphogen gradients are essential for embryo development. Here, we analyze mathematically a model of morphogen gradient (such as Dpp in Drosophila wing imaginal disc) formation in the presence of non-receptors with both diffusion of free morphogens and the movement of morphogens bound to non-receptors. Under the assumption of rapid degradation of unbound morphogen, we introduce a method of functional boundary value problem and prove the existence, uniqueness and linear stability of a biologically acceptable steady-state solution. Next, we investigate the robustness of this steady-state solution with respect to significant changes in the morphogen synthesis rate. We prove that the model is able to produce robust biological morphogen gradients when production and degradation rates of morphogens are large enough and non-receptors are abundant. Our results provide mathematical and biological insight to a mechanism of achieving stable robust long distance morphogen gradients. Key elements of this mechanism are rapid turnover of morphogen to non-receptors of neighoring cells resulting in significant degradation and transport of non-receptor-morphogen complexes, the latter moving downstream through a "bucket brigade" process.

  4. Harmine promotes osteoblast differentiation through bone morphogenetic protein signaling

    SciTech Connect

    Yonezawa, Takayuki; Lee, Ji-Won; Hibino, Ayaka; Asai, Midori; Hojo, Hironori; Cha, Byung-Yoon; Teruya, Toshiaki; Nagai, Kazuo; Chung, Ung-Il; Yagasaki, Kazumi; and others

    2011-06-03

    Highlights: {yields} Harmine promotes the activity and mRNA expression of ALP. {yields} Harmine enhances the expressions of osteocalcin mRNA and protein. {yields} Harmine induces osteoblastic mineralization. {yields} Harmine upregulates the mRNA expressions of BMPs, Runx2 and Osterix. {yields} BMP signaling pathways are involved in the actions of harmine. -- Abstract: Bone mass is regulated by osteoblast-mediated bone formation and osteoclast-mediated bone resorption. We previously reported that harmine, a {beta}-carboline alkaloid, inhibits osteoclast differentiation and bone resorption in vitro and in vivo. In this study, we investigated the effects of harmine on osteoblast proliferation, differentiation and mineralization. Harmine promoted alkaline phosphatase (ALP) activity in MC3T3-E1 cells without affecting their proliferation. Harmine also increased the mRNA expressions of the osteoblast marker genes ALP and Osteocalcin. Furthermore, the mineralization of MC3T3-E1 cells was enhanced by treatment with harmine. Harmine also induced osteoblast differentiation in primary calvarial osteoblasts and mesenchymal stem cell line C3H10T1/2 cells. Structure-activity relationship studies using harmine-related {beta}-carboline alkaloids revealed that the C3-C4 double bond and 7-hydroxy or 7-methoxy group of harmine were important for its osteogenic activity. The bone morphogenetic protein (BMP) antagonist noggin and its receptor kinase inhibitors dorsomorphin and LDN-193189 attenuated harmine-promoted ALP activity. In addition, harmine increased the mRNA expressions of Bmp-2, Bmp-4, Bmp-6, Bmp-7 and its target gene Id1. Harmine also enhanced the mRNA expressions of Runx2 and Osterix, which are key transcription factors in osteoblast differentiation. Furthermore, BMP-responsive and Runx2-responsive reporters were activated by harmine treatment. Taken together, these results indicate that harmine enhances osteoblast differentiation probably by inducing the expressions of

  5. Chlorpyrifos and Chlorpyrifos-Oxon Inhibit Axonal Growth by Interfering with the Morphogenic Activity of Acetylcholinesterase

    PubMed Central

    Yang, Dongren; Howard, Angela; Bruun, Donald; Ajua-Alemanj, Mispa; Pickart, Cecile; Lein, Pamela J.

    2008-01-01

    A primary role of acetylcholinesterase (AChE) is regulation of cholinergic neurotransmission by hydrolysis of synaptic acetylcholine. In the developing nervous system, however, AChE also functions as a morphogenic factor to promote axonal growth. This raises the question of whether organophosphorus pesticides (OPs) that are known to selectively bind to and inactivate the enzymatic function of AChE also interfere with its morphogenic function to perturb axonogenesis. To test this hypothesis, we exposed primary cultures of sensory neurons derived from embryonic rat dorsal root ganglia (DRG) to chlorpyrifos (CPF) or its oxon metabolite (CPFO). Both OPs significantly decreased axonal length at concentrations that had no effect on cell viability, protein synthesis or the enzymatic activity of AChE. Comparative analyses of the effects of CPF and CPFO on axonal growth in DRG neurons cultured from AChE nullizygous (AChE−/−) versus wildtype (AChE+/+) mice indicated that while these OPs inhibited axonal growth in AChE+/+ DRG neurons, they had no effect on axonal growth in AChE−/− DRG neurons. However, transfection of AChE−/− DRG neurons with cDNA encoding full-length AChE restored the wildtype response to the axon inhibitory effects of OPs. These data indicate that inhibition of axonal growth by OPs requires AChE, but the mechanism involves inhibition of the morphogenic rather than enzymatic activity of AChE. These findings suggest a novel mechanism for explaining not only the functional deficits observed in children and animals following developmental exposure to OPs, but also the increased vulnerability of the developing nervous system to OPs. PMID:18076960

  6. Chlorpyrifos and chlorpyrifos-oxon inhibit axonal growth by interfering with the morphogenic activity of acetylcholinesterase

    SciTech Connect

    Yang Dongren; Howard, Angela; Bruun, Donald; Ajua-Alemanj, Mispa; Pickart, Cecile; Lein, Pamela J.

    2008-04-01

    A primary role of acetylcholinesterase (AChE) is regulation of cholinergic neurotransmission by hydrolysis of synaptic acetylcholine. In the developing nervous system, however, AChE also functions as a morphogenic factor to promote axonal growth. This raises the question of whether organophosphorus pesticides (OPs) that are known to selectively bind to and inactivate the enzymatic function of AChE also interfere with its morphogenic function to perturb axonogenesis. To test this hypothesis, we exposed primary cultures of sensory neurons derived from embryonic rat dorsal root ganglia (DRG) to chlorpyrifos (CPF) or its oxon metabolite (CPFO). Both OPs significantly decreased axonal length at concentrations that had no effect on cell viability, protein synthesis or the enzymatic activity of AChE. Comparative analyses of the effects of CPF and CPFO on axonal growth in DRG neurons cultured from AChE nullizygous (AChE{sup -/-}) versus wild type (AChE{sup +/+}) mice indicated that while these OPs inhibited axonal growth in AChE{sup +/+} DRG neurons, they had no effect on axonal growth in AChE{sup -/-} DRG neurons. However, transfection of AChE{sup -/-} DRG neurons with cDNA encoding full-length AChE restored the wild type response to the axon inhibitory effects of OPs. These data indicate that inhibition of axonal growth by OPs requires AChE, but the mechanism involves inhibition of the morphogenic rather than enzymatic activity of AChE. These findings suggest a novel mechanism for explaining not only the functional deficits observed in children and animals following developmental exposure to OPs, but also the increased vulnerability of the developing nervous system to OPs.

  7. Bone Morphogenetic Protein Type I Receptor Antagonists Decrease Growth and Induce Cell Death of Lung Cancer Cell Lines

    PubMed Central

    Langenfeld, Elaine; Hong, Charles C.; Lanke, Gandhi; Langenfeld, John

    2013-01-01

    Bone morphogenetic proteins (BMPs) are highly conserved morphogens that are essential for normal development. BMP-2 is highly expressed in the majority of non-small cell lung carcinomas (NSCLC) but not in normal lung tissue or benign lung tumors. The effects of the BMP signaling cascade on the growth and survival of cancer cells is poorly understood. We show that BMP signaling is basally active in lung cancer cell lines, which can be effectively inhibited with selective antagonists of the BMP type I receptors. Lung cancer cell lines express alk2, alk3, and alk6 and inhibition of a single BMP receptor was not sufficient to decrease signaling. Inhibition of more than one type I receptor was required to decrease BMP signaling in lung cancer cell lines. BMP receptor antagonists and silencing of BMP type I receptors with siRNA induced cell death, inhibited cell growth, and caused a significant decrease in the expression of inhibitor of differentiation (Id1, Id2, and Id3) family members, which are known to regulate cell growth and survival in many types of cancers. BMP receptor antagonists also decreased clonogenic cell growth. Knockdown of Id3 significantly decreased cell growth and induced cell death of lung cancer cells. H1299 cells stably overexpressing Id3 were resistant to growth suppression and induction of cell death induced by the BMP antagonist DMH2. These studies suggest that BMP signaling promotes cell growth and survival of lung cancer cells, which is mediated through its regulation of Id family members. Selective antagonists of the BMP type I receptors represents a potential means to pharmacologically treat NSCLC and other carcinomas with an activated BMP signaling cascade. PMID:23593444

  8. Delivery Systems for Bone Morphogenetic Protein (BMP) for Repair of Battle Incurred Bone Injuries.

    DTIC Science & Technology

    1987-11-01

    infections, congenital malformations that fail to heal are eligible for BMP treatment. I (my child/my ward) will be one of 50 patients to be treated with...Fusions in Dogs 6. Craniotomy Defects in Sheep t0 7. Craniotomy Defects in Monkeys 10 8. BMP Delivery System of Bone Matrix Non Collagenous 11 Proteins...effects. The most important and indispensptle substitutes for experiments in human beings are adult mongrel dogs, monkeys, and sheep . Experimental .S

  9. Bioglass as a carrier for reindeer bone protein extract in the healing of rat femur defect.

    PubMed

    Tölli, Hanna; Kujala, Sauli; Levonen, Katri; Jämsä, Timo; Jalovaara, Pekka

    2010-05-01

    Bioactive glasses have been developed as scaffolds for bone tissue engineering but combination with reindeer bone protein extract has not been evaluated. We investigated the effects of bone protein extract implants (5-40 mg dosages) with bioglass (BG) carrier on the healing of rat femur defects. Bioglass implants and untreated defects served as controls. All doses of extract increased bone formation compared with the control groups, and bone union was enhanced with doses of 10 mg or more. In comparison with untreated defect, mean cross-sectional bone area at the defect site was greater when implants with BG + 15 mg of extract or bioglass alone were used, bone density at the defect site was higher in all bioglass groups with and without bone extract, and the BG + 15 mg extract dosage marginally increased bone torsional stiffness in mechanical testing. Bioglass performed well as a carrier candidate for reindeer bone protein extract.

  10. Intrinsic facilitation of adult peripheral nerve regeneration by the Sonic hedgehog morphogen.

    PubMed

    Martinez, Jose A; Kobayashi, Masaki; Krishnan, Anand; Webber, Christine; Christie, Kimberly; Guo, GuiFang; Singh, Vandana; Zochodne, Douglas W

    2015-09-01

    Intrinsic molecular determinants of neurodevelopmental outcomes assume new, albeit related roles during adult neural regeneration. Here we studied and identified a facilitatory role for Sonic hedgehog protein (Shh), a morphogen that influences motor neuron floor plate architecture, during adult peripheral neuron regeneration. Shh and its receptors were expressed in adult dorsal root ganglia (DRG) neurons, axons and glia and trended toward higher levels following axotomy injury. Knockdown of Shh in adult sensory neurons resulted in decreased outgrowth and branching in vitro, identifying a role for Shh in facilitating outgrowth. The findings argued for an intrinsic action to support neuron regeneration. Support of advancement and turning however, were not identified in adult sensory neuron growth cones in response to local extrinsic gradients of Shh. That intrinsic Shh supported the regrowth of peripheral nerves after injury was confirmed by the analysis of axon regrowth from the proximal stumps of transected sciatic nerves. By exposing regenerating axons to local infusions of Shh siRNA in vivo within a conduit bridging the transected proximal and distal stumps, we achieved local knockdown of Shh. In response, there was attenuated axonal and Schwann cell outgrowth beyond the transection zone. Unlike its role during neurodevelopment, Shh facilitates but does not confer regenerative outgrowth properties to adult neurons alone. Exploring the differing properties of morphogens and related proteins in the adult nervous system identifies new and important roles for them. Copyright © 2015. Published by Elsevier Inc.

  11. Outcomes of bone morphogenetic protein-2 in mature adults: posterolateral non-instrument-assisted lumbar decompression and fusion.

    PubMed

    Hamilton, D Kojo; Jones-Quaidoo, Sean M; Sansur, Charles; Shaffrey, Christopher I; Oskouian, Rod; Jane, John A

    2008-05-01

    Bone morphogenic protein products enable lumber spine fusion. Few outcome studies have been performed to evaluate function and pain relief after posterior lumber decompression for degenerative disease, and few studies have provided detailed results of posterior lumbar fusion in elderly patients. This retrospective analysis presents a comprehensive examination of spinal fusion, functional outcomes, and pain relief in a growing elderly population in which a BMP was used. Fifty-five patients, 25 men and 30 women (moderately disabled to bedridden), with both mean and median ages of 68 years, underwent surgery for symptoms of lumbar degenerative disease between August 2003 and June 2004. Surgery involved multilevel lumbar total laminectomies with medial facetectomies and posterior lateral fusion, which was performed using INFUSE Bone Graft (Medtronic Sofamor Dane K. Inc, Minneapolis, MN) with recombinant human BMP-2 as the active ingredient. Forty-seven patients (22 men and 25 women) were available for follow-up and participated in this study. Of these 47 patients, the average number of levels decompressed and fused was 2. Thirteen patients had 1 level, 18 patients with 2 levels, 15 patients with 3 levels, and 1 patient with 4 levels. An analysis of fusion was performed using computed tomography beginning at an average of 6 months (range, 3-36 months) postsurgery. At an average of 34 months (range, 29-36 months) of follow-up, 2 questionnaires--the Modified Oswestry Low Back Pain Disability Questionnaire and the SF-12 Health Survey--were completed by the patient. Long-term follow-up indicates that more than 85% of patients exhibited high functioning ability and had improved index scores and pain relief. Patients with improved pain and function scores also had better than average health status. In addition, grading the patients' fusion rates with the Lenke fusion scale [J Spinal Disord 5(4) (1992) 433-442] showed an 80% fusion (Lenke Grades A and B) rate. The use of rh

  12. Characterization of Osteoblastic and Osteolytic Proteins in Prostate Cancer Bone Metastases

    PubMed Central

    Larson, Sandy; Zhang, Xiaotun; Dumpit, Ruth; Coleman, Ilsa; Lakely, Bryce; Roudier, Martine; Higano, Celestia; True, Lawrence D.; Lange, Paul H.; Montgomery, Bruce; Corey, Eva; Nelson, Peter S.; Vessella, Robert L.; Morrissey, Colm

    2014-01-01

    Background Approximately 90% of patients who die of Prostate Cancer (PCa) have bone metastases, which promote a spectrum of osteoblastic, osteolytic or mixed bone responses. Numerous secreted proteins have been reported to promote osteoblastic or osteolytic bone responses. We determined whether previously identified and/or novel proteins were associated with the osteoblastic or osteolytic response in clinical specimens of PCa bone metastases. Methods Gene expression was analyzed on 14 PCa metastases from 11 patients by microarray profiling and qRT-PCR, and protein expression was analyzed on 33 PCa metastases from 30 patients by immunohistochemistry on highly osteoblastic and highly osteolytic bone specimens. Results Transcript and protein levels of BMP-2, BMP-7, DKK-1, ET-1 and Sclerostin were not significantly different between osteoblastic and osteolytic metastases. However, levels of OPG, PGK1 and Substance P proteins were increased in osteoblastic samples. In addition, Emu1, MMP-12 and sFRP-1 were proteins identified with a novel role of being associated with either the osteoblastic or osteolytic bone response. Conclusions This is the first detailed analysis of bone remodeling proteins in human specimens of PCa bone metastases. Three proteins not previously shown to be involved may have a role in the PCa bone response. Furthermore, our data suggests that the relative expression of numerous, rather than a single, bone remodeling proteins determine the bone response in PCa bone metastases. PMID:23334979

  13. The Structure and Function of Non-Collagenous Bone Proteins

    NASA Technical Reports Server (NTRS)

    Hook, Magnus

    1997-01-01

    The long-term goal for this program is to determine the structural and functional relationships of bone proteins and proteins that interact with bone. This information will used to design useful pharmacological compounds that will have a beneficial effect in osteoporotic patients and in the osteoporotic-like effects experienced on long duration space missions. The first phase of this program, funded under a cooperative research agreement with NASA through the Texas Medical Center, aimed to develop powerful recombinant expression systems and purification methods for production of large amounts of target proteins. Proteins expressed in sufficient'amount and purity would be characterized by a variety of structural methods, and made available for crystallization studies. In order to increase the likelihood of crystallization and subsequent high resolution solution of structures, we undertook to develop expression of normal and mutant forms of proteins by bacterial and mammalian cells. In addition to the main goals of this program, we would also be able to provide reagents for other related studies, including development of anti-fibrotic and anti-metastatic therapeutics.

  14. Diet-induced weight loss: the effect of dietary protein on bone.

    PubMed

    Tang, Minghua; O'Connor, Lauren E; Campbell, Wayne W

    2014-01-01

    High-protein (>30% of energy from protein or >1.2 g/kg/day) and moderately high-protein (22% to 29% of energy from protein or 1.0 to 1.2 g/kg/day) diets are popular for weight loss, but the effect of dietary protein on bone during weight loss is not well understood. Protein may help preserve bone mass during weight loss by stimulating insulin-like growth factor 1, a potent bone anabolism stimulator, and increasing intestinal calcium absorption. Protein-induced acidity is considered to have minimal effect on bone resorption in adults with normal kidney function. Both the quantity and predominant source of protein influence changes in bone with diet-induced weight loss. Higher-protein, high-dairy diets may help attenuate bone loss during weight loss.

  15. Photoencapsulation of bone morphogenetic protein-2 and periosteal progenitor cells improve tendon graft healing in a bone tunnel.

    PubMed

    Chen, Chih-Hwa; Liu, Hsia-Wei; Tsai, Ching-Lin; Yu, Chung-Ming; Lin, I-Hsuan; Hsiue, Ging-Ho

    2008-03-01

    Tissue-engineered solutions for promoting the tendon graft incorporation within the bone tunnel appear to be promising. To determine the feasibility that conjugation of hyaluronic acid-tethered bone morphogenetic protein-2 can be used to stimulate periosteal progenitor cells direct fibrocartilagenous attachment and new bone formation in an extra-articular tendon-bone healing model. Controlled laboratory study. A total of 42 mature New Zealand White rabbits were used. The long digitorum extensor tendon was transplanted into a bone tunnel of the proximal tibia. The tendon was pulled through a drill hole in the proximal tibia and attached to the medial aspect of the tibia. Photopolymerizable hydrogel based on poly (ethylene glycol) diacrylate with hyaluronic acid-tethered bone morphogenetic protein-2 was injected and photogelated in a bone tunnel. Histological and biomechanical examination of the tendon-bone interface was evaluated at postoperative weeks 3 and 6. Histological analysis showed an interface fibrocartilage and new bone formed by photoencapsulation of bone morphogenetic protein-2 and periosteal progenitor cells at 6 weeks. Biomechanical testing revealed higher maximum pullout strength and stiffness in experimental groups with a statistically significant difference at 3 and 6 weeks after tendon transplantation. The healing tendon-bone interface undergoes a gradual remodeling process; it appears that photoencapsulation of bone morphogenetic protein-2 and periosteal progenitor cells possesses a powerful inductive ability between the tendon and the bone to incorporate the healing in a rabbit model. Novel technologies, such as those described in this study, including photopolymerization and tissue engineering, may provide minimally invasive therapeutic procedures via arthroscopy to enhance biological healing after reconstruction of the anterior cruciate ligament.

  16. A radioimmunoassay for bone Gla protein (BGP) in human plasma.

    PubMed

    Johansen, J S; Mølholm Hansen, J E; Christiansen, C

    1987-03-01

    To study the value of bone Gla protein (BGP) as a biochemical marker of normal bone physiology and metabolic bone disorders, we have developed a radioimmunoassay (RIA) for the detection of BGP in human plasma. Antibodies were generated in rabbits immunized with purified calf BGP conjugated to thyroglobulin. Human plasma BGP reacted identically with the calf BGP standard, thus demonstrating the suitability of the assay to measure plasma BGP levels in man. The RIA is sensitive, accurate, and technically simple. Plasma BGP levels were determined in normal subjects (N = 35) and in patients with hypothyroidism (N = 10), hyperthyroidism (N = 22) and chronic renal failure (N = 35). The mean (+/- 1 SEM) concentration of plasma BGP in normal subjects was 1.27 +/- 0.07 nmol/l. Plasma BGP was significantly increased in patients with hyperthyroidism, 4.04 +/- 0.78 nmol/l (P less than 0.001) and chronic renal failure, 10.17 +/- 2.47 nmol/l (P less than 0.001). Low concentrations were found in patients with hypothyroidism, 0.74 +/- 0.11 nmol/l (P less than 0.01). Our studies indicate that plasma BGP provides a useful technique in the diagnosis of patients with bone disease.

  17. A new recombinant human bone morphogenetic protein-2 carrier for bone regeneration.

    PubMed

    Yokota, S; Sonohara, S; Yoshida, M; Murai, M; Shimokawa, S; Fujimoto, R; Fukushima, S; Kokubo, S; Nozaki, K; Takahashi, K; Uchida, T; Yokohama, S; Sonobe, T

    2001-07-31

    A gelatin sponge was formed by foaming and heat treating a gelatin solution, followed by coating the solid with poly(D,L-lactic-co-glycolic acid) to reinforce the gelatin framework. This sponge was tested for its suitability as a biodegradable porous, recombinant human bone morphogenetic protein (rhBMP)-2 carrier. Incorporation of rhBMP-2 into the sponge was closely related to its bulk density of gelatin sponge. The calcium content in the sponges, as assessed by an ectopic bone formation assay in rats, increased with the increasing sponge bulk density. Histologic and peripheral quantitative computed tomography analysis of implants in this ectopic assay system revealed cell growth throughout the carrier in 4 weeks after implantation regardless gelatin bulk density. The carrier containing rhBMP-2 maintained its three-dimensional structure after implantation; the carrier resisted collapse caused by soft tissue pressure during rapid bone formation as assessed by soft X-ray photographs. These results indicate that this newly developed sponge has excellent carrier characteristics to introduce rhBMP-2 into areas needed for bone regeneration.

  18. Stimulation of bone healing by sustained bone morphogenetic protein 2 (BMP-2) delivery.

    PubMed

    Faßbender, Mirja; Minkwitz, Susann; Strobel, Catrin; Schmidmaier, Gerhard; Wildemann, Britt

    2014-05-14

    The aim of the study was to investigate the effect of a sustained release of bone morphogenetic protein2 (BMP-2) incorporated in a polymeric implant coating on bone healing. In vitro analysis revealed a sustained, but incomplete BMP-2 release until Day 42. For the in vivo study, the rat tibia osteotomy was stabilized either with control or BMP-2 coated wires, and the healing progress was followed by micro computed tomography (µCT), biomechanical testing and histology at Days 10, 28, 42 and 84. MicroCT showed an accelerated formation of mineralized callus, as well as remodeling and an increase of mineralized/total callus volume (p=0.021) at Day 42 in the BMP-2 group compared to the control. Histology revealed an increased callus mineralization at Days 42 and 84 (p=0.006) with reduced cartilage at Day 84 (p=0.004) in the BMP-2 group. Biomechanical stiffness was significantly higher in the BMP-2 group (p=0.045) at Day 42. In summary, bone healing was enhanced after sustained BMP-2 application compared to the control. Using the same drug delivery system, but a burst release of BMP-2, a previous published study showed a similar positive effect on bone healing. Distinct differences in the healing outcome might be explained due to the different BMP release kinetics and dosages. However, further studies are necessary to adapt the optimal release profiles to physiological mechanisms.

  19. Morphogenic role for acetylcholinesterase in axonal outgrowth during neural development.

    PubMed Central

    Bigbee, J W; Sharma, K V; Gupta, J J; Dupree, J L

    1999-01-01

    Acetylcholinesterase (AChE) is the enzyme that hydrolyzes the neurotransmitter acetylcholine at cholinergic synapses and neuromuscular junctions. However, results from our laboratory and others indicate that AChE has an extrasynaptic, noncholinergic role during neural development. This article is a review of our findings demonstrating the morphogenic role of AChE, using a neuronal cell culture model. We also discuss how these data suggest that AChE has a cell adhesive function during neural development. These results could have additional significance as AChE is the target enzyme of agricultural organophosphate and carbamate pesticides as well as the commonly used household organophosphate chlorpyrifos (Dursban). Prenatal exposure to these agents could have adverse effects on neural development by interfering with the morphogenic function of AChE. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 Figure 7 PMID:10229710

  20. Cartilage morphogenetic proteins: role in joint development, homoeostasis, and regeneration

    PubMed Central

    Reddi, A

    2003-01-01

    Background: Articular cartilage homoeostasis is critical for joint function. The steady state homoeostasis of articular cartilage is a balance between anabolic morphogens such as cartilage derived morphogenetic proteins (CDMPs) and bone morphogenetic proteins (BMPs) of the BMP family and catabolic cytokines such as interleukin (IL)1, IL17, and tumour necrosis factor α. Although bone and articular cartilage are adjacent tissues, there is a profound difference in their regeneration potential. Bone has the highest potential for regeneration. On the other hand, articular cartilage is recalcitrant to repair. Objective: To examine the hypothesis that the feeble innate regeneration ability of cartilage is due to the preponderance of catabolic cytokines such as IL1 and IL17. Results: During a systematic investigation of CDMPs and cytokines IL17B (chondroleukin) was found in bovine articular cartilage. Discussion and conclusions: BMP-7 and IL17B are present in articular cartilage and synthesised in chondrocytes as shown by northern blots and real-time reverse transcription-polymerase chain reaction. The coexistence of anabolic morphogens and catabolic cytokines in articular cartilage has important implications for cartilage homoeostasis and regeneration. The networks of signalling systems of morphogens and cytokines determine the net capacity for regenerative morphogenesis of articular cartilage. Finally, the feeble innate capacity for articular cartilage may be improved by targeted therapy by soluble receptors to block catabolic cytokines. PMID:14532155

  1. A Computational Analysis of Bone Formation in the Cranial Vault in the Mouse

    PubMed Central

    Lee, Chanyoung; Richtsmeier, Joan T.; Kraft, Reuben H.

    2015-01-01

    Bones of the cranial vault are formed by the differentiation of mesenchymal cells into osteoblasts on a surface that surrounds the brain, eventually forming mineralized bone. Signaling pathways causative for cell differentiation include the actions of extracellular proteins driven by information from genes. We assume that the interaction of cells and extracellular molecules, which are associated with cell differentiation, can be modeled using Turing’s reaction–diffusion model, a mathematical model for pattern formation controlled by two interacting molecules (activator and inhibitor). In this study, we hypothesize that regions of high concentration of an activator develop into primary centers of ossification, the earliest sites of cranial vault bone. In addition to the Turing model, we use another diffusion equation to model a morphogen (potentially the same as the morphogen associated with formation of ossification centers) associated with bone growth. These mathematical models were solved using the finite volume method. The computational domain and model parameters are determined using a large collection of experimental data showing skull bone formation in mouse at different embryonic days in mice carrying disease causing mutations and their unaffected littermates. The results show that the relative locations of the five ossification centers that form in our model occur at the same position as those identified in experimental data. As bone grows from these ossification centers, sutures form between the bones. PMID:25853124

  2. Use of bone morphogenetic proteins in mesenchymal stem cell stimulation of cartilage and bone repair

    PubMed Central

    Scarfì, Sonia

    2016-01-01

    The extracellular matrix-associated bone morphogenetic proteins (BMPs) govern a plethora of biological processes. The BMPs are members of the transforming growth factor-β protein superfamily, and they actively participate to kidney development, digit and limb formation, angiogenesis, tissue fibrosis and tumor development. Since their discovery, they have attracted attention for their fascinating perspectives in the regenerative medicine and tissue engineering fields. BMPs have been employed in many preclinical and clinical studies exploring their chondrogenic or osteoinductive potential in several animal model defects and in human diseases. During years of research in particular two BMPs, BMP2 and BMP7 have gained the podium for their use in the treatment of various cartilage and bone defects. In particular they have been recently approved for employment in non-union fractures as adjunct therapies. On the other hand, thanks to their potentialities in biomedical applications, there is a growing interest in studying the biology of mesenchymal stem cell (MSC), the rules underneath their differentiation abilities, and to test their true abilities in tissue engineering. In fact, the specific differentiation of MSCs into targeted cell-type lineages for transplantation is a primary goal of the regenerative medicine. This review provides an overview on the current knowledge of BMP roles and signaling in MSC biology and differentiation capacities. In particular the article focuses on the potential clinical use of BMPs and MSCs concomitantly, in cartilage and bone tissue repair. PMID:26839636

  3. Post-translational processing of chicken bone phosphoproteins. Identification of bone (phospho)protein kinase.

    PubMed Central

    Mikuni-Takagaki, Y; Glimcher, M J

    1990-01-01

    We have detected a protein kinase which phosphorylates bone phosphoproteins (BPPs) in the detergent extract of the membranous fractions in the periosteal bone strips of 12-day-embryonic-chick tibia. This enzyme, tentatively named BPP kinase, has a catalytic subunit of Mr approximately 39,000, utilizes GTP as well as ATP as a phospho-group donor, is inhibited by 2,3-bisphosphoglycerate and heparin, and is therefore similar to casein kinase II. The enzyme can phosphorylate dephosphorylated proteins such as casein, phosvitin and chicken BPPs, but the last-named are preferred substrates. The in vitro-phosphorylation-assay products of this enzyme in the extract were indistinguishable on an SDS/polyacrylamide gel from the major [32P]phosphoproteins metabolically labelled in the embryonic-chick bone tissue. The regulatory mechanisms of the phosphorylation process of BPPs by BPP kinase as well as the potential role of this enzyme in mineralization are discussed. Images Fig. 1. Fig. 4. PMID:2363697

  4. Quantitative multivariate analysis of dynamic multicellular morphogenic trajectories.

    PubMed

    White, Douglas E; Sylvester, Jonathan B; Levario, Thomas J; Lu, Hang; Streelman, J Todd; McDevitt, Todd C; Kemp, Melissa L

    2015-07-01

    Interrogating fundamental cell biology principles that govern tissue morphogenesis is critical to better understanding of developmental biology and engineering novel multicellular systems. Recently, functional micro-tissues derived from pluripotent embryonic stem cell (ESC) aggregates have provided novel platforms for experimental investigation; however elucidating the factors directing emergent spatial phenotypic patterns remains a significant challenge. Computational modelling techniques offer a unique complementary approach to probe mechanisms regulating morphogenic processes and provide a wealth of spatio-temporal data, but quantitative analysis of simulations and comparison to experimental data is extremely difficult. Quantitative descriptions of spatial phenomena across multiple systems and scales would enable unprecedented comparisons of computational simulations with experimental systems, thereby leveraging the inherent power of computational methods to interrogate the mechanisms governing emergent properties of multicellular biology. To address these challenges, we developed a portable pattern recognition pipeline consisting of: the conversion of cellular images into networks, extraction of novel features via network analysis, and generation of morphogenic trajectories. This novel methodology enabled the quantitative description of morphogenic pattern trajectories that could be compared across diverse systems: computational modelling of multicellular structures, differentiation of stem cell aggregates, and gastrulation of cichlid fish. Moreover, this method identified novel spatio-temporal features associated with different stages of embryo gastrulation, and elucidated a complex paracrine mechanism capable of explaining spatiotemporal pattern kinetic differences in ESC aggregates of different sizes.

  5. Calcium Phosphate Scaffolds Combined with Bone Morphogenetic Proteins or Mesenchymal Stem Cells in Bone Tissue Engineering

    PubMed Central

    Sun, Han; Yang, Hui-Lin

    2015-01-01

    Objective: The purpose of this study was to review the current status of calcium phosphate (CaP) scaffolds combined with bone morphogenetic proteins (BMPs) or mesenchymal stem cells (MSCs) in the field of bone tissue engineering (BTE). Date Sources: Data cited in this review were obtained primarily from PubMed and Medline in publications from 1979 to 2014, with highly regarded older publications also included. The terms BTE, CaP, BMPs, and MSC were used for the literature search. Study Selection: Reviews focused on relevant aspects and original articles reporting in vitro and/or in vivo results concerning the efficiency of CaP/BMPs or CaP/MSCs composites were retrieved, reviewed, analyzed, and summarized. Results: An ideal BTE product contains three elements: Scaffold, growth factors, and stem cells. CaP-based scaffolds are popular because of their outstanding biocompatibility, bioactivity, and osteoconductivity. However, they lack stiffness and osteoinductivity. To solve this problem, composite scaffolds of CaP with BMPs have been developed. New bone formation by CaP/BMP composites can reach levels similar to those of autografts. CaP scaffolds are compatible with MSCs and CaP/MSC composites exhibit excellent osteogenesis and stiffness. In addition, a CaP/MSC/BMP scaffold can repair bone defects more effectively than an autograft. Conclusions: Novel BTE products possess remarkable osteoconduction and osteoinduction capacities, and exhibit balanced degradation with osteogenesis. Further work should yield safe, viable, and efficient materials for the repair of bone lesions. PMID:25881610

  6. Targeting G-Protein Signaling for the Therapeutics of Prostate Tumor Bone Metastases and the Associated Chronic Bone Pain

    DTIC Science & Technology

    2013-07-01

    results in increased activity/expression of key pain-sensing receptor channels, such as TRPV1 , such that the channels are constitutively activated...Keywords: Prostate Cancer Bone Metastasis, Bone Cancer Pain, Heterotrimeric G protein betagamma subunits, G protein coupled receptors (GPCRs), TRPV1 ...cell growth, migration and invasion in vitro, as well as mediating GPCR-regulated TRPV1 channel function in cultured mouse sensory neurons (Aim 1

  7. Targeting G-Protein Signaling for the Therapeutics of Prostate Tumor Bone Metastases and the Associated Chronic Bone Pain

    DTIC Science & Technology

    2015-09-01

    results in increased activity/expression of key pain-sensing receptor channels, such as TRPV1 , such that the channels are constitutively activated...Keywords: Prostate Cancer Bone Metastasis, Bone Cancer Pain, Heterotrimeric G protein betagamma subunits, G protein coupled receptors (GPCRs), TRPV1 ...vitro, as well as mediating GPCR-regulated TRPV1 channel function in cultured mouse sensory neurons (Aim 1) Major Goal/Objective 1: Determine the

  8. Expression of human bone-related proteins in the hematopoietic microenvironment.

    PubMed Central

    Long, M W; Williams, J L; Mann, K G

    1990-01-01

    Given the intimate relationship between bone and bone marrow, we hypothesized that the human bone marrow may function as a source (or reservoir) of bone-forming progenitor cells. We observed a population of cells within the bone marrow which produce bone-specific or bone-related proteins. The production of these proteins was developmentally regulated in human long-term bone marrow cell cultures; the bone protein-producing cells (BPPC) are observed under serum-free, short-term culture conditions, respond to bone-related and not hematopoietic growth factors, and are derived from a population of low-density, nonadherent, My10-negative (or low My10 density), marrow cells (My10 is an antigen found on most hematopoietic progenitor cells). Cultivation of marrow-derived BPPC in secondary, serum-containing cultures results in their differentiation into osteoblastlike cells. At this stage of development, BPPC produce an extracellular matrix which incorporates both bone-related proteins and radiolabeled calcium. Human bone marrow BPPC thus represent a newly described cell phenotype important to both bone and hematopoietic cell biology. Images PMID:2243119

  9. An Improved Immunostaining and Imaging Methodology to Determine Cell and Protein Distributions within the Bone Environment

    PubMed Central

    Akkiraju, Hemanth; Bonor, Jeremy; Nohe, Anja

    2015-01-01

    Bone is a dynamic tissue that undergoes multiple changes throughout its lifetime. Its maintenance requires a tight regulation between the cells embedded within the bone matrix, and an imbalance among these cells may lead to bone diseases such as osteoporosis. Identifying cell populations and their proteins within bone is necessary for understanding bone biology. Immunolabeling is one approach used to visualize proteins in tissues. Efficient immunolabeling of bone samples often requires decalcification, which may lead to changes in the structural morphology of the bone. Recently, methyl-methacrylate embedding of non-decalcified tissue followed by heat-induced antigen retrieval has been used to process bone sections for immunolabeling. However, this technique is applicable for bone slices below 50-µm thickness while fixed on slides. Additionally, enhancing epitope exposure for immunolabeling is still a challenge. Moreover, imaging bone cells within the bone environment using standard confocal microscopy is difficult. Here we demonstrate for the first time an improved methodology for immunolabeling non-decalcified bone using a testicular hyaluronidase enzyme-based antigen retrieval technique followed by two-photon fluorescence laser microscopy (TPLM) imaging. This procedure allowed us to image key intracellular proteins in bone cells while preserving the structural morphology of the cells and the bone. PMID:26718242

  10. Calcium homeostasis and bone metabolic responses to protein diets and energy restriction: a randomized control trial

    USDA-ARS?s Scientific Manuscript database

    Despite some beneficial effects on bone, high protein diets are conventionally considered a primary dietary risk factor for osteoporosis and bone fracture due to the acid load associated with protein catabolism. To test the hypothesis that high dietary protein diets do not negatively affect calcium ...

  11. Podocan-like protein: a novel small leucine-rich repeat matrix protein in bone.

    PubMed

    Mochida, Yoshiyuki; Kaku, Masaru; Yoshida, Keiko; Katafuchi, Michitsuna; Atsawasuwan, Phimon; Yamauchi, Mitsuo

    2011-07-01

    Recently, significant attention has been drawn to the biology of small leucine-rich repeat proteoglycans (SLRPs) due to their multiple functionalities in various cell types and tissues. Here, we characterize a novel SLRP member, "Podocan-like (Podnl) protein" identified by a bioinformatics approach. The Podnl protein has a signal peptide, a unique cysteine-rich N-terminal cluster, 21 leucine-rich repeat (LRR) motifs, and one putative N-glycosylation site. This protein is structurally similar to podocan in SLRPs. The gene was highly expressed in mineralized tissues and in osteoblastic cells and the high expression level was observed at and after matrix mineralization in vitro. Podnl was enriched in newly formed bones based on immunohistochemical analysis. When Podnl was transfected into osteoblastic cells, the protein with N-glycosylation was detected mainly in the cultured medium, indicating that Podnl is a secreted N-glycosylated protein. The endogenous Podnl protein was also present in bone matrix. These data provide a new insight into our understanding of the emerging SLRP functions in bone formation.

  12. Prefabrication of vascularized bone flap induced by recombinant human bone morphogenetic protein 2 (rhBMP-2).

    PubMed

    Alam, M I; Asahina, I; Seto, I; Oda, M; Enomoto, S

    2003-10-01

    An experimental model for the prefabrication of a vascularized bone flap was developed in this study. To form vascularized bone in the desired configuration and to increase the survival rate of the grafted bone, a muscle vascularized pedicle (MVP) was transformed into vascularized bone by the inducer recombinant human bone morphogenetic protein 2 (rhBMP-2). The muscle flap (8 x 8 mm) raised on saphenous vessels in the rat thigh was sandwiched between same-size collagen (Terudermis) sheets in the presence or absence of impregnated 25 microg of rhBMP-2 for the experimental group and the control group, respectively. The flaps were harvested 1, 2 and 3 weeks postoperatively. Bone transformation was detected by gross examination, radiology, and histologic testing. No evidence of muscle tissue transformation was found in control flaps, whereas all of the experimental flaps produced new bone. Saphenous vessels were observed to supply the new bone upon harvesting, and the newly formed vascularized bone showed good configuration with shape of the Terudermis sheet. This study indicates that this model of effective bone reconstruction could be potentially applied in a therapeutic setting.

  13. Gene gun transferring-bone morphogenetic protein 2 (BMP-2) gene enhanced bone fracture healing in rabbits

    PubMed Central

    Li, Wenju; Wei, Haifeng; Xia, Chunmei; Zhu, Xiaomeng; Hou, Guozhu; Xu, Feng; Song, Xinghua; Zhan, Yulin

    2015-01-01

    Purpose: Transferring the bone morphogenetic protein 2 (BMP-2) genes into the tissues or cells can improve the bone healing of the fracture has been widely accepted. We evaluated the efficiency of using gene gun to transfer the BMP-2 gene thereby affected the healing of a fractured bone. Methods: The vector coding for BMP-2 was constructed by a non-replicating encephalo-myocarditis virus (ECMV)-based vector. The segmental bone defect (1.5 cm) model was created by a wire-saw at the middle part of the radius bone of the New Zealand white rabbits. Then either BMP-2 gene or control vector without BMP-2 gene was injected into the tissues around the fracture site. Healing of the defects was monitored radiographically for 9 weeks, bone consolidation was determined by the Lane-Sandhu score pre- and post-operatively, which can evaluated bone formation, bone connect and bone plasticity. Results: The radiographic score and bone consolidation rates were significantly higher in animals injected with BMP-2 gene group as compared with control vector-injected animals (P<0.05). The control group still showed no radiological signs of stable healing. Western-blot and RT-PCR showed BMP-2 expression was significant increase in the tissues around the site of osseous lesions in comparison with the control vector-injected animals (P<0.05). Conclusions: Our results suggested that BMP-2 gene transferred by gene gun could increase the expression of BMP-2 protein and improved the bone callus formation therefore shortened the time of bone defect healing. PMID:26884910

  14. The effect of whey acidic protein fractions on bone loss in the ovariectomised rat.

    PubMed

    Kruger, Marlena C; Plimmer, Gabrielle G; Schollum, Linda M; Haggarty, Neill; Ram, Satyendra; Palmano, Kate

    2005-08-01

    Bovine milk has been shown to contain bioactive components with bone-protective properties. Earlier studies on bovine milk whey protein showed that it suppressed bone resorption in the female ovariectomised rat. A new osteotropic component was subsequently identified in the whey basic protein fraction, but bone bioactivity may also be associated with other whey fractions. In the present study, we investigated whether acidic protein fractions isolated from bovine milk whey could prevent bone loss in mature ovariectomised female rats. Six-month-old female rats were ovariectomised (OVX) or left intact (sham). The OVX rats were randomised into four groups. One group remained the control (OVX), whereas three groups were fed various whey acidic protein fractions from milk whey as 3 g/kg diet for 4 months. Outcomes were bone mineral density, bone biomechanics and markers of bone turnover. Bone mineral density of the femurs indicated that one of the whey AF over time caused a recovery of bone lost from OVX. Plasma C-telopeptide of type I collagen decreased significantly in all groups except OVX control over time, indicating an anti-resorptive effect of whey acidic protein. Biomechanical data showed that the AF may affect bone architecture as elasticity was increased by one of the whey AF. The femurs of AF-supplemented rats all showed an increase in organic matter. This is the first report of an acidic whey protein fraction isolated from milk whey that may support the recovery of bone loss in vivo.

  15. Healing of segmental bone defects with granular porous hydroxyapatite augmented with recombinant human osteogenic protein-1 or autologous bone marrow.

    PubMed

    den Boer, Frank C; Wippermann, Burkhard W; Blokhuis, Taco J; Patka, Peter; Bakker, Fred C; Haarman, Henk J Th M

    2003-05-01

    Hydroxyapatite is a synthetic bone graft, which is used for the treatment of bone defects and nonunions. However, it is a rather inert material with no or little intrinsic osteoinductive activity. Recombinant human osteogenic protein-1 (rhOP-1) is a very potent biological agent, that enhances osteogenesis during bone repair. Bone marrow contains mesenchymal stem cells, which are capable of new bone formation. Biosynthetic bone grafts were created by the addition of rhOP-1 or bone marrow to granular porous hydroxyapatite. The performance of these grafts was tested in a sheep model and compared to the results of autograft, which is clinically the standard treatment of bone defects and nonunions. A 3 cm segmental bone defect was made in the tibia and fixed with an interlocking intramedullary nail. There were five treatment groups: no implant (n=6), autograft (n=8), hydroxyapatite alone (n=8), hydroxyapatite loaded with rhOP-1 (n=8), and hydroxyapatite loaded with autologous bone marrow (n=8). At 12 weeks, healing of the defect was evaluated with radiographs, a torsional test to failure, and histological examination of longitudinal sections through the defect. Torsional strength and stiffness of the healing tibiae were about two to three times higher for autograft and hydroxyapatite plus rhOP-1 or bone marrow compared to hydroxyapatite alone and empty defects. The mean values of both combination groups were comparable to those of autograft. There were more unions in defects with hydroxyapatite plus rhOP-1 than in defects with hydroxyapatite alone. Although the differences were not significant, histological examination revealed that there was more often bony bridging of the defect in both combination groups and the autograft group than in the group with hydroxyapatite alone. Healing of bone defects, treated with porous hydroxyapatite, can be enhanced by the addition of rhOP-1 or autologous bone marrow. The results of these composite biosynthetic grafts are equivalent to

  16. Protein and mineral characterisation of rendered meat and bone meal.

    PubMed

    Buckley, M; Penkman, K E H; Wess, T J; Reaney, S; Collins, M J

    2012-10-01

    We report the characterisation of meat and bone meal (MBM) standards (Set B-EFPRA) derived from cattle, sheep, pig and chicken, each rendered at four different temperatures (133, 137, 141 and 145 °C). The standards, prepared for an EU programme STRATFEED (to develop new methodologies for the detection and quantification of illegal addition of mammalian tissues in feeding stuffs), have been widely circulated and used to assess a range of methods for identification of the species composition of MBM. The overall state of mineral alteration and protein preservation as a function of temperature was monitored using small angle X-ray diffraction (SAXS), amino acid composition and racemization analyses. Progressive increases in protein damage and mineral alteration in chicken and cattle standards was observed. In the case of sheep and pig, there was greater damage to the proteins and alteration of the minerals at the lowest treatment temperature (133 °C), suggesting that the thermal treatments must have been compromised in some way. This problem has probably impacted upon the numerous studies which tested methods against these heat treatments. We use protein mass spectrometric methods to explore if thermostable proteins could be used to identify rendered MBM. In more thermally altered samples, so-called 'thermostable' proteins such as osteocalcin which has been proposed as a ideal target to speciate MBM were no longer detectable, but the structural protein type I collagen could be used to differentiate all four species, even in the most thermally altered samples. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Relative and combined effects of ethanol and protein deficiency on bone manganese and copper.

    PubMed

    González-Pérez, José M; González-Reimers, Emilio; DeLaVega-Prieto, María José; Durán-Castellón, María del Carmen; Viña-Rodríguez, José; Galindo-Martín, Luis; Alvisa-Negrín, Julio; Santolaria-Fernández, Francisco

    2012-06-01

    Both manganese and copper may affect bone synthesis. Bone content of both metals can be altered in alcoholics, although controversy exists regarding this matter. To analyse the relative and combined effects of ethanol and a low protein diet on bone copper and manganese, and their relationships with bone structure and metabolism, including trabecular bone mass (TBM), osteoid area (OA), osteocalcin (OCN), insulin-like growth factor-1 (IGF-1), parathyroid hormone (PTH), urinary hydroxyproline (uHP) and vitamin D. Adult male Sprague-Dawley rats were divided into four groups. The control rats received a 18% protein-containing diet; a second group, an isocaloric, 2% protein-containing diet; a third one, an isocaloric, 36% ethanol-containing diet and a fourth, an isocaloric diet containing 2% protein and 36% ethanol. After sacrifice, TBM and OA were histomorphometrically assessed; bone and serum manganese and copper were determined by atomic absorption spectrophotometry, and serum OCN, IGF-1, PTH, uHP and vitamin D by radioimmunoassay. Ethanol-fed rats showed decreased TBM and bone manganese. Significant relationships existed between bone manganese and TBM, serum IGF-1 and OCN. Ethanol leads to a decrease in bone manganese, related to decreased bone mass and bone synthesis. No alterations were found in bone copper.

  18. Combined intervention of dietary soybean proteins and swim training: effects on bone metabolism in ovariectomized rats.

    PubMed

    Figard, Hélène; Mougin, Fabienne; Gaume, Vincent; Berthelot, Alain

    2006-01-01

    Soybean proteins, a rich source of isoflavones, taken immediately after an ovariectomy prevent bone loss in rats. Exercise-induced stimuli are essential for bone growth. Few studies exist about the combined effects of swim training and soybean protein supplementation on bone metabolism. So, the purpose of this study was to investigate, in 48 female Sprague-Dawley rats (12 weeks old) the effects of an 8-week swim-training regimen (1 h/day, 5 days/week) and dietary soybean proteins (200 g/kg diet) on bone metabolism. Rats were randomly assigned to four groups: (1) ovariectomized fed with a semisynthetic control diet; (2) ovariectomized fed with a soybean protein-enriched semisynthetic diet; (3) ovariectomized trained to exercise and fed with control diet; (4) ovariectomized trained to exercise and fed with a soybean protein diet. Following the treatment period, body weight gain was identical in the four groups. Soybean protein supplementation increased bone calcium content, and reduced plasma osteocalcin values, without significant modification of calcium balance and net calcium absorption. Swim training enhanced plasma and bone calcium content and calcium balance and net calcium absorption. It did not modify either plasma osteocalcin values or urinary deoxypyridinoline excretion. Both exercise and soybean protein intake increased plasma on bone calcium without modifying net calcium absorption or bone markers. In conclusion, we demonstrated, in ovariectomized rats, that swimming exercise and dietary supplementation with soy proteins do not have synergistic effects on calcium metabolism and bone markers.

  19. Acid diet (high-meat protein) effects on calcium metabolism and bone health.

    PubMed

    Cao, Jay J; Nielsen, Forrest H

    2010-11-01

    Update recent advancements regarding the effect of high-animal protein intakes on calcium utilization and bone health. Increased potential renal acid load resulting from a high protein (intake above the current Recommended Dietary Allowance of 0.8 g protein/kg body weight) intake has been closely associated with increased urinary calcium excretion. However, recent findings do not support the assumption that bone is lost to provide the extra calcium found in urine. Neither whole body calcium balance is, nor are bone status indicators, negatively affected by the increased acid load. Contrary to the supposed detrimental effect of protein, the majority of epidemiological studies have shown that long-term high-protein intake increases bone mineral density and reduces bone fracture incidence. The beneficial effects of protein such as increasing intestinal calcium absorption and circulating IGF-I whereas lowering serum parathyroid hormone sufficiently offset any negative effects of the acid load of protein on bone health. On the basis of recent findings, consuming protein (including that from meat) higher than current Recommended Dietary Allowance for protein is beneficial to calcium utilization and bone health, especially in the elderly. A high-protein diet with adequate calcium and fruits and vegetables is important for bone health and osteoporosis prevention.

  20. Effect of the morphogene bolA on the permeability of the Escherichia coli outer membrane.

    PubMed

    Freire, Patrick; Vieira, Helena L A; Furtado, Ana R; de Pedro, Miguel A; Arraiano, Cecília M

    2006-07-01

    Escherichia coli bolA is a morphogene involved in stress response and cell division. Overexpression of bolA induces biofilm formation and affects the levels of carboxypeptidases PBP5, PBP6 and beta-lactamase AmpC. In this study, we have shown that changes in the expression of bolA result in alterations in the properties of the outer membrane. The sensitivity to detergents and vancomycin was reduced when bolA was overexpressed and fluorescent probes indicated that different levels of bolA had an effect on outer membrane protein accessibility. Moreover, bolA was shown to be involved in the modulation of the OmpF/OmpC balance.

  1. The effect of enamel matrix proteins and deproteinized bovine bone mineral on heterotopic bone formation.

    PubMed

    Donos, Nikolaos; Kostopoulos, Lambros; Tonetti, Maurizio; Karring, Thorkild; Lang, Niklaus P

    2006-08-01

    To evaluate the osteoinductive potential of deproteinized bovine bone mineral (DBBM) and an enamel matrix derivative (EMD) in the muscle of rats. Sixteen rats were used in this study. The animals were divided in three groups. Group A: a pouch was created in one of the pectoralis profundis muscles of the thorax of the rats and DBBM particles (Bio-Oss) were placed into the pouch. Healing: 60 days. Group B: a small pouch was created on both pectoralis profundis muscles at each side of the thorax midline. In one side, a mixture of EMD (Emdogain) mixed with DBBM was placed into one of the pouches, whereas in the contralateral side of the thorax the pouch was implanted with DBBM mixed with the propylene glycol alginate (PGA--carrier for enamel matrix proteins of EMD). Healing: 60 days. Group C: the same procedure as group B, but with a healing period of 120 days. Qualitative histological analysis of the results was performed. At 60 days, the histological appearance of the DBBM particles implanted alone was similar to that of the particles implanted together with EMD or PGA at both 60 and 120 days. The DBBM particles were encapsulated into a connective tissue stroma and an inflammatory infiltrate. At 120 days, the DBBM particles implanted together with EMD or PGA exhibited the presence of resorption lacunae in some cases. Intramuscular bone formation was not encountered in any group. The implantation of DBBM particles alone, combined with EMD or its carrier (PGA) failed to exhibit extraskeletal, bone-inductive properties.

  2. Direct or indirect stimulation of adenosine A2A receptors enhances bone regeneration as well as bone morphogenetic protein-2.

    PubMed

    Mediero, Aránzazu; Wilder, Tuere; Perez-Aso, Miguel; Cronstein, Bruce N

    2015-04-01

    Promoting bone regeneration and repair of bone defects is a need that has not been well met to date. We have previously found that adenosine, acting via A2A receptors (A2AR) promotes wound healing and inhibits inflammatory osteolysis and hypothesized that A2AR might be a novel target to promote bone regeneration. Therefore, we determined whether direct A2AR stimulation or increasing endogenous adenosine concentrations via purine transport blockade with dipyridamole regulates bone formation. We determined whether coverage of a 3 mm trephine defect in a mouse skull with a collagen scaffold soaked in saline, bone morphogenetic protein-2 (BMP-2; 200 ng), 1 μM CGS21680 (A2AR agonist, EC50 = 160 nM), or 1 μM dipyridamole (EC50 = 32 nM) promoted bone regeneration. Microcomputed tomography examination demonstrated that CGS21680 and dipyridamole markedly enhanced bone regeneration as well as BMP-2 8 wk after surgery (60 ± 2%, 79 ± 2%, and 75 ± 1% bone regeneration, respectively, vs. 32 ± 2% in control, P < 0.001). Blockade by a selective A2AR antagonist (ZM241385, 1 μM) or deletion of A2AR abrogated the effect of CGS21680 and dipyridamole on bone regeneration. Both CGS21680 and dipyridamole treatment increased alkaline phosphatase-positive osteoblasts and diminished tartrate resistance acid phosphatase-positive osteoclasts in the defects. In vivo imaging with a fluorescent dye for new bone formation revealed a strong fluorescent signal in treated animals that was equivalent to BMP-2. In conclusion, stimulation of A2AR by specific agonists or by increasing endogenous adenosine levels stimulates new bone formation as well as BMP-2 and represents a novel approach to stimulating bone regeneration. © FASEB.

  3. Tissue-Engineered Autologous Grafts for Facial Bone Reconstruction

    PubMed Central

    Bhumiratana, Sarindr; Bernhard, Jonathan C.; Alfi, David M.; Yeager, Keith; Eton, Ryan E.; Bova, Jonathan; Shah, Forum; Gimble, Jeffrey M.; Lopez, Mandi J.; Eisig, Sidney B.; Vunjak-Novakovic, Gordana

    2016-01-01

    Facial deformities require precise reconstruction of the appearance and function of the original tissue. The current standard of care—the use of bone harvested from another region in the body—has major limitations, including pain and comorbidities associated with surgery. We have engineered one of the most geometrically complex facial bones by using autologous stromal/stem cells, without bone morphogenic proteins, using native bovine bone matrix and a perfusion bioreactor for the growth and transport of living grafts. The ramus-condyle unit (RCU), the most eminent load-bearing bone in the skull, was reconstructed using an image-guided personalized approach in skeletally mature Yucatan minipigs (human-scale preclinical model). We used clinically approved decellularized bovine trabecular bone as a scaffolding material, and crafted it into an anatomically correct shape using image-guided micromilling, to fit the defect. Autologous adipose-derived stromal/stem cells were seeded into the scaffold and cultured in perfusion for 3 weeks in a specialized bioreactor to form immature bone tissue. Six months after implantation, the engineered grafts maintained their anatomical structure, integrated with native tissues, and generated greater volume of new bone and greater vascular infiltration than either non-seeded anatomical scaffolds or untreated defects. This translational study demonstrates feasibility of facial bone reconstruction using autologous, anatomically shaped, living grafts formed in vitro, and presents a platform for personalized bone tissue engineering. PMID:27306665

  4. The Bone Morphogenetic Protein 1/Tolloid-like Metalloproteinases

    PubMed Central

    Hopkins, Delana R.; Keles, Sunduz; Greenspan, Daniel S.

    2009-01-01

    A decade ago, bone morphogenetic protein 1 (BMP1) was shown to provide the activity necessary for proteolytic removal of the C-propeptides of procollagens I–III: precursors of the major fibrillar collagens. Subsequent studies have shown BMP1 to be the prototype of a small group of extracellular metalloproteinases that play manifold roles in regulating formation of the extracellular matrix (ECM). Soon after initial cloning of BMP1, genetic studies showed the related Drosophila proteinase Tolloid (TLD) to be necessary for formation of the dorsal-ventral axis in early embryogenesis. It is now clear that the BMP1/TLD-like proteinases, conserved in species ranging from Drosophila to humans, act in dorsal-ventral patterning via activation of transforming growth factor β (TGFβ)-like proteins BMP2, BMP4 (vertebrates) and decapentaplegic (arthropods). More recently, it has become apparent that the BMP1/TLD-like proteinases are key activators of a broader subset of the TGFβ superfamily of proteins, with implications that these proteinases may be key in orchestrating formation of ECM with growth factor activation and BMP signaling in morphogenetic processes. PMID:17560775

  5. Regulation of Bone Morphogenetic Protein Signaling by ADP-ribosylation*

    PubMed Central

    Watanabe, Yukihide; Papoutsoglou, Panagiotis; Maturi, Varun; Tsubakihara, Yutaro; Hottiger, Michael O.; Heldin, Carl-Henrik; Moustakas, Aristidis

    2016-01-01

    We previously established a mechanism of negative regulation of transforming growth factor β signaling mediated by the nuclear ADP-ribosylating enzyme poly-(ADP-ribose) polymerase 1 (PARP1) and the deribosylating enzyme poly-(ADP-ribose) glycohydrolase (PARG), which dynamically regulate ADP-ribosylation of Smad3 and Smad4, two central signaling proteins of the pathway. Here we demonstrate that the bone morphogenetic protein (BMP) pathway can also be regulated by the opposing actions of PARP1 and PARG. PARG positively contributes to BMP signaling and forms physical complexes with Smad5 and Smad4. The positive role PARG plays during BMP signaling can be neutralized by PARP1, as demonstrated by experiments where PARG and PARP1 are simultaneously silenced. In contrast to PARG, ectopic expression of PARP1 suppresses BMP signaling, whereas silencing of endogenous PARP1 enhances signaling and BMP-induced differentiation. The two major Smad proteins of the BMP pathway, Smad1 and Smad5, interact with PARP1 and can be ADP-ribosylated in vitro, whereas PARG causes deribosylation. The overall outcome of this mode of regulation of BMP signal transduction provides a fine-tuning mechanism based on the two major enzymes that control cellular ADP-ribosylation. PMID:27129221

  6. Bone morphogenetic protein antagonist gremlin-1 regulates colon cancer progression.

    PubMed

    Karagiannis, George S; Musrap, Natasha; Saraon, Punit; Treacy, Ann; Schaeffer, David F; Kirsch, Richard; Riddell, Robert H; Diamandis, Eleftherios P

    2015-02-01

    Bone morphogenetic proteins (BMP) are phylogenetically conserved signaling molecules of the transforming growth factor-beta (TGF-beta) superfamily of proteins, involved in developmental and (patho)physiological processes, including cancer. BMP signaling has been regarded as tumor-suppressive in colorectal cancer (CRC) by reducing cancer cell proliferation and invasion, and by impairing epithelial-to-mesenchymal transition (EMT). Here, we mined existing proteomic repositories to explore the expression of BMPs in CRC. We found that the BMP antagonist gremlin-1 (GREM1) is secreted from heterotypic tumor-host cell interactions. We then sought to investigate whether GREM1 is contextually and mechanistically associated with EMT in CRC. Using immunohistochemistry, we showed that GREM1-expressing stromal cells harbor prominent features of myofibroblasts (i.e., cancer-associated fibroblasts), such as expression of α-smooth muscle actin and laminin-beta-1, and were in contextual proximity to invasion fronts with loss of the tight junction protein occludin and parallel nuclear accumulation of β-catenin, two prominent EMT hallmarks. Furthermore, in vitro assays demonstrated that GREM1-dependent suppression of BMP signaling results in EMT induction, characterized by cadherin switching (loss of E-cadherin-upregulation of N-cadherin) and overexpression of Snail. Collectively, our data support that GREM1 promotes the loss of cancer cell differentiation at the cancer invasion front, a mechanism that may facilitate tumor progression.

  7. Regulation of bone morphogenetic proteins in early embryonic development

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yukiyo; Oelgeschläger, Michael

    2004-11-01

    Bone morphogenetic proteins (BMPs), a large subgroup of the TGF-β family of secreted growth factors, control fundamental events in early embryonic development, organogenesis and adult tissue homeostasis. The plethora of dose-dependent cellular processes regulated by BMP signalling demand a tight regulation of BMP activity. Over the last decade, a number of proteins have been identified that bind BMPs in the extracellular space and regulate the interaction of BMPs with their cognate receptors, including the secreted BMP antagonist Chordin. In the early vertebrate embryo, the localized secretion of BMP antagonists from the dorsal blastopore lip establishes a functional BMP signalling gradient that is required for the determination of the dorsoventral or back to belly body axis. In particular, inhibition of BMP activity is essential for the formation of neural tissue in the development of vertebrate and invertebrate embryos. Here we review recent studies that have provided new insight into the regulation of BMP signalling in the extracellular space. In particular, we discuss the recently identified Twisted gastrulation protein that modulates, in concert with metalloproteinases of the Tolloid family, the interaction of Chordin with BMP and a family of proteins that share structural similarities with Chordin in the respective BMP binding domains. In addition, genetic and functional studies in zebrafish and frog provide compelling evidence that the secreted protein Sizzled functionally interacts with the Chd BMP pathway, despite being expressed ventrally in the early gastrula-stage embryo. These intriguing discoveries may have important implications, not only for our current concept of early embryonic patterning, but also for the regulation of BMP activity at later developmental stages and tissue homeostasis in the adult.

  8. Formation and maintenance of morphogen gradients: an essential role for the endomembrane system in Drosophila melanogaster wing development.

    PubMed

    Erickson, Jessica L

    2011-01-01

    As early as 1964 it was suggested that simple diffusion of morphogens away from their secretion source did not provide an adequate explanation for the formation and maintenance of morphogen gradients. Involvement of the endosome in morphogen distribution models provides an explanation for the slow, directional movement of morphogens, as well as their ability to form intracellular and extracellular gradients independent of morphogen production rates. Drosophila melanogaster morphogens Wg and Dpp form stable, steep, long-range gradients that specify the polarity of the wing disc. The process of endocytosis is imperative to the two central themes in gradient formation: active transport facilitating long-range signaling and degradation of morphogen to sustain gradient shape. This review investigates the endomembrane-mediated processes of re-secretion, degradation and argosome transport of Wg and Dpp in the hope that a better understanding of the endomembrane system will contribute to a more accurate and comprehensive model for morphogen gradient formation and maintenance.

  9. Interpretation of the FGF8 morphogen gradient is regulated by endocytic trafficking.

    PubMed

    Nowak, Matthias; Machate, Anja; Yu, Shuizi Rachel; Gupta, Mansi; Brand, Michael

    2011-02-01

    Forty years ago, it was proposed that during embryonic development and organogenesis, morphogen gradients provide positional information to the individual cells within a tissue leading to specific fate decisions. Recently, much insight has been gained into how such morphogen gradients are formed and maintained; however, which cellular mechanisms govern their interpretation within target tissues remains debated. Here we used in vivo fluorescence correlation spectroscopy and automated image analysis to assess the role of endocytic sorting dynamics on fibroblast growth factor 8 (Fgf8) morphogen gradient interpretation. By interfering with the function of the ubiquitin ligase Cbl, we found an expanded range of Fgf target gene expression and a delay of Fgf8 lysosomal transport. However, the extracellular Fgf8 morphogen gradient remained unchanged, indicating that the observed signalling changes are due to altered gradient interpretation. We propose that regulation of morphogen signalling activity through endocytic sorting allows fast feedback-induced changes in gradient interpretation during the establishment of complex patterns.

  10. Repair of bone defect in primate mandible using a bone morphogenetic protein (BMP)-hydroxyapatite-collagen composite.

    PubMed

    Asahina, I; Watanabe, M; Sakurai, N; Mori, M; Enomoto, S

    1997-09-01

    The purpose of this study was to evaluate a hydroxyapatite (HA)-collagen (Col)-bone morphogenetic protein (BMP) composite as an osteoinductive bone substitute. Partially-purified BMP from bovine bone was mechanically mixed with highly purified type I collagen from calf dermis and then subsequently mixed with pure synthetic hydroxyapatite granules or block. The HA-Col-BMP composite, or the HA-Col composite as a control, was implanted in a surgically-induced mandible bone defect (6 x 7 x 10 mm) in an adult Japanese monkey. The mandible was excised three months after implantation and studied histologically. The BMP-containing implant induced much more new bone than the control implant in all experimental animals of each group, with either HA granules or HA block. Newly formed bone was attached tightly to HA and infiltrated deeply into the pores of the HA of the BMP-containing implant, while fibrous tissue existed between the host bone and HA in the control implant. Thus, we conclude that an HA-Col-BMP composite could be a superior biomaterial for a bone substitute.

  11. 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

  12. Simvastatin enhances bone morphogenetic protein receptor type II expression

    SciTech Connect

    Hu Hong; Sung, Arthur; Zhao, Guohua; Shi, Lingfang; Qiu Daoming; Nishimura, Toshihiko; Kao, Peter N. . E-mail: peterkao@stanford.edu

    2006-01-06

    Statins confer therapeutic benefits in systemic and pulmonary vascular diseases. Bone morphogenetic protein (BMP) receptors serve essential signaling functions in cardiovascular development and skeletal morphogenesis. Mutations in BMP receptor type II (BMPR2) are associated with human familial and idiopathic pulmonary arterial hypertension, and pathologic neointimal proliferation of vascular endothelial and smooth muscle cells within small pulmonary arteries. In severe experimental pulmonary hypertension, simvastatin reversed disease and conferred a 100% survival advantage. Here, modulation of BMPR2 gene expression by simvastatin is characterized in human embryonic kidney (HEK) 293T, pulmonary artery smooth muscle, and lung microvascular endothelial cells (HLMVECs). A 1.4 kb BMPR2 promoter containing Egr-1 binding sites confers reporter gene activation in 293T cells which is partially inhibited by simvastatin. Simvastatin enhances steady-state BMPR2 mRNA and protein expression in HLMVEC, through posttranscriptional mRNA stabilization. Simvastatin induction of BMPR2 expression may improve BMP-BMPR2 signaling thereby enhancing endothelial differentiation and function.

  13. Ribosomal protein L29/HIP deficiency delays osteogenesis and increases fragility of adult bone in mice

    PubMed Central

    Oristian, Daniel S.; Sloofman, Laura G.; Zhou, Xiaozhou; Wang, Liyun; Farach-Carson, Mary C.; Kirn-Safran, Catherine B.

    2008-01-01

    SUMMARY Mice lacking HIP/RPL29, a ribosomal modulator of protein synthesis rate, display a short stature phenotype. To understand the contribution of HIP/RPL29 to bone formation and adult whole bone mechanical properties, we examined both developing and adult bone in our knockout mice. Results indicated that bone shortening in HIP/RPL29-null mice is due to delayed entry of chondro-osteoprogenitors into the cell cycle. Structural properties of adult null bones were analyzed by micro-computed tomography. Interestingly, partial preservation of cortical thickness was observed in null males indicating a gender-specific effect of the genotype on cortical bone parameters. Null males, and to a lower extent null females, displayed increased bone material toughness to counteract decreased bone size. This elevation in a bone material property was associated with increased bone mineral density only in null males. Neither male nor female null animals could withstand the same maximum load as gender-matched controls in three point-bending tests, and smaller post-yield displacements (and thus increased bone brittleness) were found for null animals. These results suggest that HIP/RPL29-deficient mice exhibit increased bone fragility due to altered matrix protein synthesis rates as a consequence of ribosomal insufficiency. Thus, sub-efficient protein translation increased fracture risk in HIP/RPL29-null animals. Taken together, these studies provide strong genetic evidence that the ability to regulate and amplify protein synthesis rates, including those proteins that regulate the cell cycle entry during skeletal development, are important determinants for establishment of normal bone mass and quality. PMID:18661500

  14. Protein intake, weight loss, and bone mineral density in postmenopausal women.

    PubMed

    Campbell, Wayne W; Tang, Minghua

    2010-10-01

    Higher protein diets are promoted for effective weight loss. Striated tissues in omnivorous diets contain high-quality protein, but limited data exist regarding their effects on bone. To examine the effects of energy restriction-induced weight loss with higher protein omnivorous diets versus lower protein vegetarian diets on bone mineral density in overweight postmenopausal women, two randomized controlled feeding studies were conducted. In Study 1, 28 women consumed 750 kcal/day energy deficit diets with 18% energy from protein via lacto-ovo vegetarian sources (normal protein, n = 15) or 30% energy from protein with 40% of protein from lean pork (higher protein, n = 13, omnivorous) for 12 weeks. In Study 2, 54 women consumed their habitual diet (control, n = 11) or 1,250 kcal/day diets with 16% energy from nonmeat protein sources (n = 14) or 26% energy from protein, including chicken (n = 15) or beef (n = 14) for 9 weeks. Study 1: With weight loss (normal protein -11.2%, higher protein -10.1%), bone mineral density was not significantly changed in normal protein (-0.003 ± 0.003 g/cm(2), -0.3%) but decreased in higher protein (-0.0167 ± 0.004 g/cm(2), -1. 4%, group-by-time p < .05). Study 2: The control, nonmeat, chicken, and beef groups lost 1.5%, 7.7%, 10.4%, and 8.1% weight and 0.0%, 0.4%, 1.1%, and 1.4% bone mineral density, respectively. The change of bone mineral density was significant for chicken and beef compared with the control (group-by-time, p < .05). Markers of calcium metabolism and bone homeostasis in blood and urine were not changed over time or differentially affected by diet. Consumption of higher protein omnivorous diets promoted decreased bone mineral density after weight loss in overweight postmenopausal women.

  15. Bone Tissue Engineering Using High Permeability Poly-epsilon-caprolactone Scaffolds Conjugated with Bone Morphogenetic Protein-2

    NASA Astrophysics Data System (ADS)

    Mitsak, Anna Guyer

    Bone is the second most commonly transplanted tissue in the United States. Limitations of current bone defect treatment options include morbidity at the autograft harvest site, mechanical failure, and poorly controlled growth factor delivery. Combining synthetic scaffolds with biologics may address these issues and reduce dependency on autografts. The ideal scaffolding system should promote tissue in-growth and nutrient diffusion, control delivery of biologics and maintain mechanical integrity during bone formation. This dissertation evaluates how scaffold permeability, conjugated bone morphogenetic protein-2 (BMP-2) and differentiation medium affect osteogenesis in vitro and bone growth in vivo.. "High" and "low" permeability polycaprolactone (PCL) scaffolds with regular architectures were manufactured using solid free form fabrication. Bone growth in vivo was evaluated in an ectopic mouse model. High permeability scaffolds promoted better 8 week bone growth, supported tissue penetration into the scaffold core, and demonstrated increased mechanical properties due to newly formed bone. Next, the effects of differentiation medium and conjugated BMP-2 on osteogenesis were compared. Conjugation may improve BMP-2 loading efficiency, help localize bone growth and control release. High permeability scaffolds were conjugated with BMP-2 using the crosslinker, sulfo-SMCC. When adipose-derived and bone marrow stromal cells were seeded onto constructs (with or without BMP-2), BMSC expressed more differentiation markers, and differentiation medium affected differentiation more than BMP-2. In vivo, scaffolds with ADSC pre-differentiated in osteogenic medium (with and without BMP-2) and scaffolds with only BMP-2 grew the most bone. Bone volume did not differ among these groups, but constructs with ADSC had evenly distributed, scaffold-guided bone growth. Analysis of two additional BMP-2 attachment methods (heparin and adsorption) showed highest conjugation efficiency for the

  16. AFM study of morphology and mechanical properties of a chimeric spider silk and bone sialoprotein protein for bone regeneration

    PubMed Central

    Gomes, Sílvia; Numata, Keiji; Leonor, Isabel B.; Mano, João F.; Reis, Rui L.; Kaplan, David L.

    2011-01-01

    Atomic force microscopy (AFM) was used to assess a new chimeric protein consisting of a fusion protein of the consensus repeat for Nephila clavipes spider dragline protein and bone sialoprotein (6mer+BSP). The elastic modulus of this protein in film form was assessed through force curves, and film surface roughness was also determined. The results showed a significant difference between the elastic modulus of the chimeric silk protein, 6mer+BSP, and control films consisting of only the silk component (6mer). The behaviour of the 6mer+BSP and 6mer proteins in aqueous solution in the presence of calcium (Ca) ions was also assessed to determine interactions between the inorganic and organic components related to bone interactions, anchoring and biomaterial network formation. The results demonstrated the formation of protein networks in the presence of Ca2+ ions, characteristics that may be important in the context of controlling materials assembly and properties related to bone-formation with this new chimeric silk-BSP protein. PMID:21370930

  17. The control of neural stem cells by morphogenic signals.

    PubMed

    Panchision, David M; McKay, Ronald D G

    2002-08-01

    A complex orchestration of stem-cell specification, expansion and differentiation is required for the proper development of the nervous system. Although progress has been made on the role of individual genes in each of these processes, there are still unresolved questions about how gene function translates to the dynamic assembly of cells into tissues. Recently, stem-cell biology has emerged as a bridge between the traditional fields of cell biology and developmental genetics. In addition to their potential therapeutic role, stem cells are being exploited as experimental 'logic chips' that integrate information and exhibit self-organizing properties. Recent studies provide new insights on how morphogenic signals coordinate major stem cell decisions to regulate the size, shape and cellular diversity of the nervous system.

  18. Bone Marrow-Derived Heparan Sulfate Potentiates The Osteogenic Activity Of Bone Morphogenetic Protein-2 (BMP-2)

    PubMed Central

    Bramono, Diah S.; Murali, Sadasivam; Rai, Bina; Ling, Ling; Poh, Wei Theng; Lim, Zophia Xuehui; Stein, Gary S.; Nurcombe, Victor; van Wijnen, Andre J.; Cool, Simon M.

    2013-01-01

    Lowering the efficacious dose of bone morphogenetic protein-2 (BMP-2) for the repair of critical-sized bone defects is highly desirable, as supra-physiological amounts of BMP-2 have an increased risk of side effects and a greater economic burden for the healthcare system. To address this need, we explored the use of heparan sulfate (HS), a structural analog of heparin, to enhance BMP-2 activity. We demonstrate that HS isolated from a bone marrow stromal cell line (HS5) and heparin each enhances BMP-2-induced osteogenesis in C2C12 myoblasts, through increased ALP activity and osteocalcin mRNA expression. Commercially available HS variants from porcine kidney and bovine lung failed to generate similar effects. Heparin and HS5 influence BMP-2 activity by (i) prolonging BMP-2 half-life, (ii) reducing interactions between BMP-2 with its antagonist noggin, and (iii) modulating BMP2 distribution on the cell surface. Importantly, long-term supplementation of HS5 but not heparin greatly enhances BMP-2-induced bone formation in vitro and in vivo. These results show that bone marrow-derived HS effectively support bone formation, and suggests its applicability in bone repair by selectively facilitating the delivery and bioavailability of BMP-2. PMID:22227436

  19. Bone reservoir: Injectable hyaluronic acid hydrogel for minimal invasive bone augmentation.

    PubMed

    Martínez-Sanz, Elena; Ossipov, Dmitri A; Hilborn, Jöns; Larsson, Sune; Jonsson, Kenneth B; Varghese, Oommen P

    2011-06-10

    A strategy has been designed to develop hyaluronic acid (HA) hydrogel for in vivo bone augmentation using minimal invasive technique. A mild synthetic procedure was developed to prepare aldehyde modified HA by incorporating an amino-glycerol side chain via amidation reaction and selective oxidation of the pendent group. This modification, upon mixing with hydrazide modified HA formed hydrazone-crosslinked hydrogel within 30s that was stable at physiological pH. In vitro experiments showed no cytotoxicity of hydrogel with the controlled release of active bone morphogenic protein-2 (BMP-2). In vivo evaluation of this gel as a BMP-2 carrier was performed by injecting gels over the rat calvarium and showed bone formation in 8 weeks in correlation with the amount of BMP-2 loaded (0, 1 and 30μg) within the gel. Furthermore, hydrogels with 30μg of BMP-2 induced less bone formation upon subcutaneous injection in comparison with subperiosteal implantation. Histological examination showed newly formed bone with a high expression of osteocalcin, osteopontin and with angiogenic bone marrow when higher BMP-2 concentration was employed. Our result suggests that novel HA hydrogels could be used as a BMP-2 carrier and can promote bone augmentation for potential orthopedic applications. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. Successful treatment of a humeral capitulum osteonecrosis with bone morphogenetic protein-7 combined with autologous bone grafting.

    PubMed

    Marsell, Richard; Hailer, Nils P

    2014-08-01

    We present the case of a 27-year-old female with subcortical osteonecrosis of the humeral capitulum. Percutaneous retrograde drilling of the lesion and application of recombinant human bone morphogenetic protein (BMP)-7 were combined with autologous bone grafting. At follow-up the patient was almost pain-free, had normalized her range of motion, and radiography showed consolidation of the lesion without any heterotopic bone formation. By timing surgery prior to subchondral collapse, biomechanical stability of the subchondral bone was maintained. To our knowledge, this is the first report on the treatment of an osteonecrosis in this location with a BMP, and this strategy could potentially be applied in other locations with juxta-articular osteonecrosis.

  1. Molecular Design of Bisphosphonate-Modified Proteins for Efficient Bone Targeting In Vivo

    PubMed Central

    Katsumi, Hidemasa; Sano, Jun-ichi; Nishikawa, Makiya; Hanzawa, Keiko; Sakane, Toshiyasu; Yamamoto, Akira

    2015-01-01

    To establish a rational molecular design for bisphosphonate (BP)-modified proteins for efficient bone targeting, a pharmacokinetic study was performed using a series of alendronate (ALN), a nitrogen-containing BP, modified proteins with various molecular weights and varying degrees of modification. Four proteins with different molecular weight—yeast glutathione reductase (GR; MW: 112,000 Da), bovine serum albumin (BSA; MW: 67,000 Da), recombinant human superoxide dismutase (SOD; MW: 32,000 Da), and chicken egg white lysozyme (LZM; MW: 14,000 Da)—were modified with ALN to obtain ALN-modified proteins. Pharmacokinetic analysis of the tissue distribution of the ALN-modified and unmodified proteins was performed after radiolabeling them with indium-111 (111In) by using a bifunctional chelating agent. Calculation of tissue uptake clearances revealed that the bone uptake clearances of 111In-ALN-modified proteins were proportional to the degree of ALN modification. 111In-GR-ALN and BSA-ALN, the two high-molecular-weight proteins, efficiently accumulated in bones, regardless of the degree of ALN modification. Approximately 36 and 34% of the dose, respectively, was calculated to be delivered to the bones. In contrast, the maximum amounts taken up by bone were 18 and 13% of the dose for 111In-SOD-ALN(32) and LZM-ALN(9), respectively, because of their high renal clearance. 111In-SOD modified with both polyethylene glycol (PEG) and ALN (111In-PEG-SOD-ALN) was efficiently delivered to the bone. Approximately 36% of the dose was estimated to be delivered to the bones. In an experimental bone metastasis mouse model, treatment with PEG-SOD-ALN significantly reduced the number of tumor cells in the bone of the mice. These results indicate that the combination of PEG and ALN modification is a promising approach for efficient bone targeting of proteins with a high total-body clearance. PMID:26287482

  2. Local accumulation time for the formation of morphogen gradients from a Lévy diffusion process

    NASA Astrophysics Data System (ADS)

    Yin, Hongwei; Wen, Xiaoqing; Zhou, Tianshou

    2013-10-01

    Morphogen gradients provide very precise spatial information on the control of cell fate specification in many developing tissues. In previous studies, morphogen gradient formation was commonly modelled as Fickian diffusion. However, the complexity of morphogen transport and anisotropy of intracellular and extracellular environments in vivo can lead to Lévy flights of morphogens. In this case, a natural question is whether morphogen gradients reach steady states on timescales relevant to developmental patterning. Here, we build and analyse a Lévy diffusion model of morphogen transport, which is based on a continuous time random walk with a long-tailed jump length distribution. Importantly, we derive the analytical expression of local accumulation time that provides a time scale that characterizes relaxation to a steady state at an arbitrary position within the patterned field, and shows that this time depends on cell positions in a nonlinear and asymmetric manner. Our analytical result provides an explicit connection between the key parameters of the problem and the time needed to reach a steady state value at an arbitrarily given position, which is important for a better understanding of tissue patterning by morphogen gradients in a more real case.

  3. High Protein Intake Improves Insulin Sensitivity but Exacerbates Bone Resorption in Immobility (WISE Study)

    NASA Technical Reports Server (NTRS)

    Heer, Martina; Smith, Scott M.; Frings-Meuthen, Petra; Zwart, Sara R.; Baecker, Natalie

    2012-01-01

    Inactivity, like bed rest (BR), causes insulin resistance (IR) and bone loss even in healthy subjects. High protein intake seems to mitigate this IR but might exacerbate bone loss. We hypothesized that high protein intake (animal:vegetable protein ratio: 60:40), isocaloric, compared to the control group plus high potassium intake would prevent IR without affecting bone turnover. After a 20-day ambulatory adaptation to controlled confinement and diet, 16 women participated in a 60-day, 6 deg head-down-tilt BR and were assigned randomly to one of the two groups. Control subjects (CON, n=8) received 1g/kg body mass/d dietary protein. Nutrition subjects (NUT, n=8) received 1.45g/kg body mass/d dietary protein plus 7.2g branched chain amino acids per day during BR. All subjects received 1670 kcal/d. Bed rest decreased glucose disposal by 35% (p<0.05) in CON. Isocaloric high protein intake prevented insulin resistance, but exacerbated bed rest induced increase in bone resorption markers C-telopeptide (> 30%) and Ntelopeptide (>20%) (both: p<0.001). Bone formation markers were unaffected by high protein intake. We conclude from these results that high protein intake might positively affect glucose tolerance, but might also foster bone loss. Further long-duration studies are mandatory before high protein intake for diabetic patients, who have an increased fracture risk, might be recommended.

  4. Differential expression of bone matrix regulatory proteins in human atherosclerotic plaques.

    PubMed

    Dhore, C R; Cleutjens, J P; Lutgens, E; Cleutjens, K B; Geusens, P P; Kitslaar, P J; Tordoir, J H; Spronk, H M; Vermeer, C; Daemen, M J

    2001-12-01

    In the present study, we examined the expression of regulators of bone formation and osteoclastogenesis in human atherosclerosis because accumulating evidence suggests that atherosclerotic calcification shares features with bone calcification. The most striking finding of this study was the constitutive immunoreactivity of matrix Gla protein, osteocalcin, and bone sialoprotein in nondiseased aortas and the absence of bone morphogenetic protein (BMP)-2, BMP-4, osteopontin, and osteonectin in nondiseased aortas and early atherosclerotic lesions. When atherosclerotic plaques demonstrated calcification or bone formation, BMP-2, BMP-4, osteopontin, and osteonectin were upregulated. Interestingly, this upregulation was associated with a sustained immunoreactivity of matrix Gla protein, osteocalcin, and bone sialoprotein. The 2 modulators of osteoclastogenesis (osteoprotegerin [OPG] and its ligand, OPGL) were present in the nondiseased vessel wall and in early atherosclerotic lesions. In advanced calcified lesions, OPG was present in bone structures, whereas OPGL was only present in the extracellular matrix surrounding calcium deposits. The observed expression patterns suggest a tight regulation of the expression of bone matrix regulatory proteins during human atherogenesis. The expression pattern of both OPG and OPGL during atherogenesis might suggest a regulatory role of these proteins not only in osteoclastogenesis but also in atherosclerotic calcification.

  5. Shape and function of the Bicoid morphogen gradient in dipteran species with different sized embryos

    PubMed Central

    Gregor, Thomas; McGregor, Alistair P.; Wieschaus, Eric F.

    2008-01-01

    The Bicoid morphogen evolved approximately 150 MYA from a Hox3 duplication and is only found in higher dipterans. A major difference between dipteran species, however, is the size of the embryo, which varies up to 5 fold. Although the expression of developmental factors scale with egg length, it remains unknown how this scaling is achieved. To test whether scaling is accounted for by the properties of Bicoid, we expressed eGFP fused to the coding region of bicoid from three dipteran species in transgenic Drosophila embryos using the Drosophila bicoid cis-regulatory and mRNA localization sequences. In such embryos, we find that Lucilia sericata and Calliphora vicina Bicoid produce gradients very similar to the endogenous Drosophila gradient and much shorter than what they would have produced in their own respective species. The common shape of the Drosophila, Lucilia and Calliphora Bicoid gradients appears to be a conserved feature of the Bicoid protein. Surprisingly, despite their similar distributions, we find that Bicoid from Lucilia and Calliphora do not rescue Drosophila bicoid mutants, suggesting that that Bicoid proteins have evolved species-specific functional amino acid differences. We also found that maternal expression and anteriorly localization of proteins other than Bcd does not necessarily give rise to a gradient; eGFP produced a uniform protein distribution. However, a shallow gradient was observed using eGFP-NLS, suggesting nuclear localization may be necessary but not sufficient for gradient formation. PMID:18328473

  6. The protein kinase LKB1 negatively regulates bone morphogenetic protein receptor signaling

    PubMed Central

    Raja, Erna; Edlund, Karolina; Kahata, Kaoru; Zieba, Agata; Morén, Anita; Watanabe, Yukihide; Voytyuk, Iryna; Botling, Johan; Söderberg, Ola; Micke, Patrick; Pyrowolakis, George; Heldin, Carl-Henrik; Moustakas, Aristidis

    2016-01-01

    The protein kinase LKB1 regulates cell metabolism and growth and is implicated in intestinal and lung cancer. Bone morphogenetic protein (BMP) signaling regulates cell differentiation during development and tissue homeostasis. We demonstrate that LKB1 physically interacts with BMP type I receptors and requires Smad7 to promote downregulation of the receptor. Accordingly, LKB1 suppresses BMP-induced osteoblast differentiation and affects BMP signaling in Drosophila wing longitudinal vein morphogenesis. LKB1 protein expression and Smad1 phosphorylation analysis in a cohort of non-small cell lung cancer patients demonstrated a negative correlation predominantly in a subset enriched in adenocarcinomas. Lung cancer patient data analysis indicated strong correlation between LKB1 loss-of-function mutations and high BMP2 expression, and these two events further correlated with expression of a gene subset functionally linked to apoptosis and migration. This new mechanism of BMP receptor regulation by LKB1 has ramifications in physiological organogenesis and disease. PMID:26701726

  7. Morphogen-based simulation model of ray growth and joint patterning during fin development and regeneration.

    PubMed

    Rolland-Lagan, Anne-Gaëlle; Paquette, Mathieu; Tweedle, Valerie; Akimenko, Marie-Andrée

    2012-03-01

    The fact that some organisms are able to regenerate organs of the correct shape and size following amputation is particularly fascinating, but the mechanism by which this occurs remains poorly understood. The zebrafish (Danio rerio) caudal fin has emerged as a model system for the study of bone development and regeneration. The fin comprises 16 to 18 bony rays, each containing multiple joints along its proximodistal axis that give rise to segments. Experimental observations on fin ray growth, regeneration and joint formation have been described, but no unified theory has yet been put forward to explain how growth and joint patterns are controlled. We present a model for the control of fin ray growth during development and regeneration, integrated with a model for joint pattern formation, which is in agreement with published, as well as new, experimental data. We propose that fin ray growth and joint patterning are coordinated through the interaction of three morphogens. When the model is extended to incorporate multiple rays across the fin, it also accounts for how the caudal fin acquires its shape during development, and regains its correct size and shape following amputation.

  8. Bone morphogenetic proteins in multiple sclerosis: Role in neuroinflammation.

    PubMed

    Eixarch, Herena; Calvo-Barreiro, Laura; Montalban, Xavier; Espejo, Carmen

    2017-02-27

    Bone morphogenetic proteins (BMPs) are growth factors that represent the largest subgroup of signalling ligands of the transforming growth factor beta (TGF-β) superfamily. Their participation in the proliferation, survival and cell fate of several cell types and their involvement in many pathological conditions are now well known. BMP expression is altered in multiple sclerosis (MS) patients, suggesting that BMPs have a role in the pathogenesis of this disease. MS is a demyelinating and neurodegenerative autoimmune disorder of the central nervous system (CNS). MS is a complex pathological condition in which genetic, epigenetic and environmental factors converge, although its aetiology remains elusive. Multifunctional molecules, such as BMPs, are extremely interesting in the field of MS because they are involved in the regulation of several adult tissues, including the CNS and the immune system. In this review, we discuss the extensive data available regarding the role of BMP signalling in neuronal progenitor/stem cell fate and focus on the participation and expression of BMPs in CNS demyelination. Additionally, we provide an overview of the involvement of BMPs as modulators of the immune system, as this subject has not been thoroughly explored even though it is of great interest in autoimmune disorders. Moreover, we describe the data on BMP signalling in autoimmunity and inflammatory diseases, including MS and its experimental models. Thus, we aim to provide an integrated view of the putative role of BMPs in MS pathogenesis and to open the field for the further development of alternative therapeutic strategies for MS patients.

  9. The effect of bone morphogenetic protein-2 on osteosarcoma metastasis

    PubMed Central

    Gill, Jonathan; Connolly, Patrick; Roth, Michael; Chung, So Hak; Zhang, Wendong; Piperdi, Sajida; Hoang, Bang; Yang, Rui; Guzik, Hillary; Gorlick, Richard; Geller, David S.

    2017-01-01

    Purpose Bone Morphogenetic Protein-2 (BMP-2) may offer the potential to enhance allograft-host osseous union in limb-salvage surgery following osteosarcoma resection. However, there is concern regarding the effect of locally applied BMP-2 on tumor recurrence and metastasis. The purpose of this project was to evaluate the effect of exogenous BMP-2 on osteosarcoma migration and invasion across a panel of tumor cell lines in vitro and to characterize the effect of BMP-2 on pulmonary osteosarcoma metastasis within a xenograft model. Experimental design The effect of BMP-2 on in vitro tumor growth and development was assessed across multiple standard and patient-derived xenograft osteosarcoma cell lines. Tumor migration capacity, invasion, and cell proliferation were characterized. In addition, the effect on metastasis was measured using a xenograft model following tail-vein injection. The effect of exogenous BMP-2 on the development of metastases was measured following both single and multiple BMP-2 administrations. Results There was no significant difference in migration capacity, invasion, or cell proliferation between the BMP-2 treated and the untreated osteosarcoma cell lines. There was no significant difference in pulmonary metastases between either the single-dose or multi-dose BMP-2 treated animals and the untreated control animals. Conclusions In the model systems tested, the addition of BMP-2 does not increase osteosarcoma proliferation, migration, invasion, or metastasis to the lungs. PMID:28264040

  10. The effect of bone morphogenetic protein-2 on osteosarcoma metastasis.

    PubMed

    Gill, Jonathan; Connolly, Patrick; Roth, Michael; Chung, So Hak; Zhang, Wendong; Piperdi, Sajida; Hoang, Bang; Yang, Rui; Guzik, Hillary; Morris, Jonathan; Gorlick, Richard; Geller, David S

    2017-01-01

    Bone Morphogenetic Protein-2 (BMP-2) may offer the potential to enhance allograft-host osseous union in limb-salvage surgery following osteosarcoma resection. However, there is concern regarding the effect of locally applied BMP-2 on tumor recurrence and metastasis. The purpose of this project was to evaluate the effect of exogenous BMP-2 on osteosarcoma migration and invasion across a panel of tumor cell lines in vitro and to characterize the effect of BMP-2 on pulmonary osteosarcoma metastasis within a xenograft model. The effect of BMP-2 on in vitro tumor growth and development was assessed across multiple standard and patient-derived xenograft osteosarcoma cell lines. Tumor migration capacity, invasion, and cell proliferation were characterized. In addition, the effect on metastasis was measured using a xenograft model following tail-vein injection. The effect of exogenous BMP-2 on the development of metastases was measured following both single and multiple BMP-2 administrations. There was no significant difference in migration capacity, invasion, or cell proliferation between the BMP-2 treated and the untreated osteosarcoma cell lines. There was no significant difference in pulmonary metastases between either the single-dose or multi-dose BMP-2 treated animals and the untreated control animals. In the model systems tested, the addition of BMP-2 does not increase osteosarcoma proliferation, migration, invasion, or metastasis to the lungs.

  11. Proteome degradation in fossils: investigating the longevity of protein survival in ancient bone

    PubMed Central

    Wadsworth, Caroline; Buckley, Mike

    2014-01-01

    RATIONALE We report the use of proteomics techniques to study how the fossil bone proteome changes in complexity over one million years. METHODS We include the attempted use of a previously unreported methodology in proteome research, to remove the dominant bone collagens using bacterial collagenase as well as conventional shotgun proteomics methodology following digestion with the protease trypsin. In this study we expand upon a set of 19 bovine sub-fossil specimens ranging over one and a half million years that had previously been shown to possess collagen, using a total of 46 LTQ-Orbitrap liquid chromatography/tandem mass spectrometry (LC/MS/MS) analyses containing 462,186 precursor ion analyses. RESULTS Although many types of proteins can typically be identified in recent bone, in degraded bone we observe a rapid loss of lower abundance proteins. Abundant serum proteins such as serum albumin and alpha-2-HS-glycoprotein appear to be more easily recovered in ancient bone, both being identified in specimens dating to the Early Pleistocene, the earliest period tested in this study. Proteins belonging to the leucine-rich repeat family such as lumican, biglycan and chondroadherin also survive well, possibly because of their interactions with bone collagen. CONCLUSIONS Of these 'survivor proteins' A2HSG shows a remarkable amount of sequence variation, making it potentially one of the most useful proteins to study for species identification and phylogenetic inference in archaeological and palaeontological bone. PMID:24519823

  12. Proteome degradation in fossils: investigating the longevity of protein survival in ancient bone.

    PubMed

    Wadsworth, Caroline; Buckley, Mike

    2014-03-30

    We report the use of proteomics techniques to study how the fossil bone proteome changes in complexity over one million years. We include the attempted use of a previously unreported methodology in proteome research, to remove the dominant bone collagens using bacterial collagenase as well as conventional shotgun proteomics methodology following digestion with the protease trypsin. In this study we expand upon a set of 19 bovine sub-fossil specimens ranging over one and a half million years that had previously been shown to possess collagen, using a total of 46 LTQ-Orbitrap liquid chromatography/tandem mass spectrometry (LC/MS/MS) analyses containing 462,186 precursor ion analyses. Although many types of proteins can typically be identified in recent bone, in degraded bone we observe a rapid loss of lower abundance proteins. Abundant serum proteins such as serum albumin and alpha-2-HS-glycoprotein appear to be more easily recovered in ancient bone, both being identified in specimens dating to the Early Pleistocene, the earliest period tested in this study. Proteins belonging to the leucine-rich repeat family such as lumican, biglycan and chondroadherin also survive well, possibly because of their interactions with bone collagen. Of these 'survivor proteins' A2HSG shows a remarkable amount of sequence variation, making it potentially one of the most useful proteins to study for species identification and phylogenetic inference in archaeological and palaeontological bone. © 2014 The Authors. Rapid Communications in Mass Spectrometry published by John Wiley & Sons Ltd.

  13. Short term effects on bone quality associated with consumption of soy protein isolate and other dietary protein sources in rapidly growing female rats

    USDA-ARS?s Scientific Manuscript database

    Beneficial effects of soy protein consumption on bone quality have been reported. The effects of other dietary protein sources such as whey protein hydrolysate (WPH) and rice protein isolate (RPI) on bone growth has been less well examined. The current study compared effects of feeding soy protein i...

  14. The role of bone marrow-derived cells in bone fracture repair in a green fluorescent protein chimeric mouse model

    SciTech Connect

    Taguchi, Kazuhiro . E-mail: s3061@nms.ac.jp; Ogawa, Rei; Migita, Makoto; Hanawa, Hideki; Ito, Hiromoto; Orimo, Hideo

    2005-05-27

    We investigated the role of bone marrow cells in bone fracture repair using green fluorescent protein (GFP) chimeric model mice. First, the chimeric model mice were created: bone marrow cells from GFP-transgenic C57BL/6 mice were injected into the tail veins of recipient wild-type C57BL/6 mice that had been irradiated with a lethal dose of 10 Gy from a cesium source. Next, bone fracture models were created from these mice: closed transverse fractures of the left femur were produced using a specially designed device. One, three, and five weeks later, fracture lesions were extirpated for histological and immunohistochemical analyses. In the specimens collected 3 and 5 weeks after operation, we confirmed calluses showing intramembranous ossification peripheral to the fracture site. The calluses consisted of GFP- and osteocalcin-positive cells at the same site, although the femur consisted of only osteocalcin-positive cells. We suggest that bone marrow cells migrated outside of the bone marrow and differentiated into osteoblasts to make up the calluses.

  15. Platelet-rich plasma for long bone healing.

    PubMed

    Lenza, Mário; Ferraz, Silvia de Barros; Viola, Dan Carai Maia; Santos, Oscar Fernando Pavão dos; Cendoroglo Neto, Miguel; Ferretti, Mario

    2013-01-01

    To evaluate effectiveness of the use of platelet-rich plasma as coadjuvant for union of long bones. The search strategy included the Cochrane Library (via Central) and MEDLINE (via PubMed). There were no limits as to language or publication media. The latest search strategy was conducted in December 2011. It included randomized clinical trials that evaluated the use of platelet-rich plasma as coadjuvant medication to accelerate union of long bones (acute fractures, pseudoarthrosis and bone defects). The outcomes of interest for this review include bone regeneration, adverse events, costs, pain, and quality of life. The authors selected eligible studies, evaluated the methodological quality, and extracted the data. It was not possible to perform quantitative analysis of the grouped studies (meta-analyses). Two randomized prospective clinical trials were included, with a total of 148 participants. One of them compared recombinant human morphogenic bone protein-7 versus platelet-rich plasma for the treatment of pseudoarthrosis; the other evaluated the effects of three coadjuvant treatments for union of valgising tibial osteotomies (platelet-rich plasma, platelet-rich plasma plus bone marrow stromal cells, and no coadjuvant treatment). Both had low statistical power and moderate to high risk of bias. There was no conclusive evidence that sustained the use of platelet-rich plasma as a coadjuvant to aid bone regeneration of fractures, pseudoarthrosis, or bone defects.

  16. Platelet-rich plasma for long bone healing

    PubMed Central

    Lenza, Mário; Ferraz, Silvia de Barros; Viola, Dan Carai Maia; dos Santos, Oscar Fernando Pavão; Cendoroglo, Miguel; Ferretti, Mario

    2013-01-01

    ABSTRACT Objective: To evaluate effectiveness of the use of platelet-rich plasma as coadjuvant for union of long bones. Methods: The search strategy included the Cochrane Library (via Central) and MEDLINE (via PubMed). There were no limits as to language or publication media. The latest search strategy was conducted in December 2011. It included randomized clinical trials that evaluated the use of platelet-rich plasma as coadjuvant medication to accelerate union of long bones (acute fractures, pseudoarthrosis and bone defects). The outcomes of interest for this review include bone regeneration, adverse events, costs, pain, and quality of life. The authors selected eligible studies, evaluated the methodological quality, and extracted the data. It was not possible to perform quantitative analysis of the grouped studies (meta-analyses). Results: Two randomized prospective clinical trials were included, with a total of 148 participants. One of them compared recombinant human morphogenic bone protein-7 versus platelet-rich plasma for the treatment of pseudoarthrosis; the other evaluated the effects of three coadjuvant treatments for union of valgising tibial osteotomies (platelet-rich plasma, platelet-rich plasma plus bone marrow stromal cells, and no coadjuvant treatment). Both had low statistical power and moderate to high risk of bias. Conclusion: There was no conclusive evidence that sustained the use of platelet-rich plasma as a coadjuvant to aid bone regeneration of fractures, pseudoarthrosis, or bone defects. PMID:23579757

  17. Bone Marrow Protein Oxidation in Response to Ionizing Radiation in C57BL/6J Mice

    PubMed Central

    Kim, Yong-Chul; Barshishat-Kupper, Michal; McCart, Elizabeth A.; Mueller, Gregory P.; Day, Regina M.

    2014-01-01

    The bone marrow is one of the most radio-sensitive tissues. Accidental ionizing radiation exposure can damage mature blood cells and hematopoietic progenitor/stem cells, and mortality can result from hematopoietic insufficiency and infection. Ionizing radiation induces alterations in gene and protein expression in hematopoietic tissue. Here we investigated radiation effects on protein carbonylation, a primary marker for protein oxidative damage. C57BL/6 mice were either sham irradiated or exposed to 7.5 Gy 60Co (0.6 Gy/min) total body irradiation. Bone marrow was obtained 24 h post-irradiation. Two dimensional (2-D) gel electrophoresis and Oxyblot immunodetection were used to discover carbonylated proteins, and peptide mass fingerprinting was performed for identification. 2D gels allowed the detection of 13 carbonylated proteins in the bone marrow; seven of these were identified, with two pairs of the same protein. Baseline levels of carbonylation were found in 78 kDa glucose-related protein, heat shock protein cognate 71 KDa, actin, chitinase-like protein 3 (CHI3L1), and carbonic anhydrase 2 (CAII). Radiation increased carbonylation in four proteins, including CHI3L1 and CAII, and induced carbonylation of one additional protein (not identified). Our findings indicate that the profile of specific protein carbonylation in bone marrow is substantially altered by ionizing radiation. Accordingly, protein oxidation may be a mechanism for reduced cell viability. PMID:28250382

  18. Administration of growth hormone in selectively protein-deprived rats decreases BMD and bone strength.

    PubMed

    Ammann, Patrick; Brennan, Tara C; Mekraldi, Samia; Aubert, Michel L; Rizzoli, René

    2010-06-01

    Isocaloric protein undernutrition is associated with decreased bone mass and decreased bone strength, together with lower IGF-I levels. It remains unclear whether administration of growth hormone (GH) corrects these alterations in bone metabolism. Six-month-old female rats were fed isocaloric diets containing either 2.5% or 15% casein for 2 weeks. Bovine growth hormone (bGH, 0.5 or 2.5mg/kg of body weight) or vehicle was then administered as subcutaneous injections, twice daily, to rats on either diet for 4 weeks. At the proximal tibia, analysis of bone mineral density (BMD), maximal load and histomorphometry were performed. In addition, urinary deoxypyridinoline, plasma osteocalcin and IGF-I concentrations were measured. Weight was monitored weekly. bGH caused a dose-dependent increase in plasma IGF-I regardless of the dietary protein content. However, bGH dose-dependently decreased BMD and bone strength in rats fed the low-protein diet. There was no significant effect of bGH on BMD in rats fed the normal protein diet within this short-term treatment period, however bone formation as detected by histomorphometry was improved in this group but not the low-protein group. Osteoclast surface was increased in the low-protein bGH-treated animals only. Changes in bone turnover markers were detectable under both normal and low-protein diets. These results emphasize the major importance of dietary protein intake in the bone response to short-term GH administration, and highlight the need for further investigation into the effects of GH treatment in patients with reduced protein intake. Copyright 2010 Elsevier Inc. All rights reserved.

  19. Response to Nodal morphogen gradient is determined by the kinetics of target gene induction

    PubMed Central

    Dubrulle, Julien; Jordan, Benjamin M; Akhmetova, Laila; Farrell, Jeffrey A; Kim, Seok-Hyung; Solnica-Krezel, Lilianna; Schier, Alexander F

    2015-01-01

    Morphogen gradients expose cells to different signal concentrations and induce target genes with different ranges of expression. To determine how the Nodal morphogen gradient induces distinct gene expression patterns during zebrafish embryogenesis, we measured the activation dynamics of the signal transducer Smad2 and the expression kinetics of long- and short-range target genes. We found that threshold models based on ligand concentration are insufficient to predict the response of target genes. Instead, morphogen interpretation is shaped by the kinetics of target gene induction: the higher the rate of transcription and the earlier the onset of induction, the greater the spatial range of expression. Thus, the timing and magnitude of target gene expression can be used to modulate the range of expression and diversify the response to morphogen gradients. DOI: http://dx.doi.org/10.7554/eLife.05042.001 PMID:25869585

  20. Dietary animal and plant protein and human bone health: a whole foods approach.

    PubMed

    Massey, Linda K

    2003-03-01

    Urinary calcium excretion is strongly related to net renal acid excretion. The catabolism of dietary protein generates ammonium ion and sulfates from sulfur-containing amino acids. Bone citrate and carbonate are mobilized to neutralize these acids, so urinary calcium increases when dietary protein increases. Common plant proteins such as soy, corn, wheat and rice have similar total S per g of protein as eggs, milk and muscle from meat, poultry and fish. Therefore increasing intake of purified proteins from either animal or plant sources similarly increases urinary calcium. The effects of a protein on urinary calcium and bone metabolism are modified by other nutrients found in that protein food source. For example, the high amount of calcium in milk compensates for urinary calcium losses generated by milk protein. Similarly, the high potassium levels of plant protein foods, such as legumes and grains, will decrease urinary calcium. The hypocalciuric effect of the high phosphate associated with the amino acids of meat at least partially offsets the hypercalciuric effect of the protein. Other food and dietary constituents such as vitamin D, isoflavones in soy, caffeine and added salt also have effects on bone health. Many of these other components are considered in the potential renal acid load of a food or diet, which predicts its effect on urinary acid and thus calcium. "Excess" dietary protein from either animal or plant proteins may be detrimental to bone health, but its effect will be modified by other nutrients in the food and total diet.

  1. A proteomic study of protein variation between osteopenic and age-matched control bone tissue.

    PubMed

    Chaput, Christopher D; Dangott, Lawrence J; Rahm, Mark D; Hitt, Kirby D; Stewart, Donald S; Wayne Sampson, H

    2012-05-01

    The focus of this study was to identify changes in protein expression within the bone tissue environment between osteopenic and control bone tissue of human femoral neck patients with osteoarthritis. Femoral necks were compared from osteopenic patients and age-matched controls. A new method of bone protein extraction was developed to provide a swift, clear view of the bone proteome. Relative changes in protein expression between control and osteopenic samples were quantified using difference gel electrophoresis (DIGE) technology after affinity chromatographic depletion of albumin and IgG. The proteins that were determined to be differentially expressed were identified using standard liquid chromatography mass spectrometry (LC/MS/MS) and database searching techniques. In order to rule out blood contamination, blood from age-matched osteoporotic, osteopenic and controls were analyzed in a similar manner. Image analysis of the DIGE gels indicated that 145 spots in the osteopenic bone samples changed at least ± 1.5-fold from the control samples (P < 0.05). Three of the proteins were identified by LC/MS/MS. Of the proteins that increased in the osteopenic femurs, two were especially significant: carbonic anhydrase I and phosphoglycerate kinase 1. Apolipoprotein A-I was the most prominent protein that significantly decreased in the osteopenic femurs. The blood samples revealed no significant differences between groups for any of these proteins. In conclusion, carbonic anhydrase I, phosphoglycerate kinase 1 and apolipoprotein A-I appeared to be the most significant variations of proteins in patients with osteopenia and osteoarthritis.

  2. Uncovering Molecular Bases Underlying Bone Morphogenetic Protein Receptor Inhibitor Selectivity

    PubMed Central

    Alsamarah, Abdelaziz; LaCuran, Alecander E.; Oelschlaeger, Peter; Hao, Jijun; Luo, Yun

    2015-01-01

    Abnormal alteration of bone morphogenetic protein (BMP) signaling is implicated in many types of diseases including cancer and heterotopic ossifications. Hence, small molecules targeting BMP type I receptors (BMPRI) to interrupt BMP signaling are believed to be an effective approach to treat these diseases. However, lack of understanding of the molecular determinants responsible for the binding selectivity of current BMP inhibitors has been a big hindrance to the development of BMP inhibitors for clinical use. To address this issue, we carried out in silico experiments to test whether computational methods can reproduce and explain the high selectivity of a small molecule BMP inhibitor DMH1 on BMPRI kinase ALK2 vs. the closely related TGF-β type I receptor kinase ALK5 and vascular endothelial growth factor receptor type 2 (VEGFR2) tyrosine kinase. We found that, while the rigid docking method used here gave nearly identical binding affinity scores among the three kinases; free energy perturbation coupled with Hamiltonian replica-exchange molecular dynamics (FEP/H-REMD) simulations reproduced the absolute binding free energies in excellent agreement with experimental data. Furthermore, the binding poses identified by FEP/H-REMD led to a quantitative analysis of physical/chemical determinants governing DMH1 selectivity. The current work illustrates that small changes in the binding site residue type (e.g. pre-hinge region in ALK2 vs. ALK5) or side chain orientation (e.g. Tyr219 in caALK2 vs. wtALK2), as well as a subtle structural modification on the ligand (e.g. DMH1 vs. LDN193189) will cause distinct binding profiles and selectivity among BMP inhibitors. Therefore, the current computational approach represents a new way of investigating BMP inhibitors. Our results provide critical information for designing exclusively selective BMP inhibitors for the development of effective pharmacotherapy for diseases caused by aberrant BMP signaling. PMID:26133550

  3. Loss of endogenous bone morphogenetic protein-6 aggravates renal fibrosis.

    PubMed

    Dendooven, Amélie; van Oostrom, Olivia; van der Giezen, Dionne M; Leeuwis, Jan Willem; Snijckers, Cristel; Joles, Jaap A; Robertson, Elizabeth J; Verhaar, Marianne C; Nguyen, Tri Q; Goldschmeding, Roel

    2011-03-01

    Bone morphogenetic protein-6 (BMP-6) suppresses inflammatory genes in renal proximal tubular cells and regulates iron metabolism by inducing hepcidin. In diabetic patients, an increase of myofibroblast progenitor cells (MFPCs), also known as fibrocytes, was found to be associated with decreased BMP-6 expression. We hypothesized that loss of endogenous BMP-6 would aggravate renal injury and fibrosis. Wild type (WT) and BMP-6 null mice underwent unilateral ureteral obstruction. In WT mice, ureteral obstruction down-regulated BMP-6. Obstructed kidneys of BMP-6 null mice showed more casts (1.5-fold), epithelial necrosis (1.4-fold), and brush border loss (1.3-fold). This was associated with more inflammation (1.8-fold more CD45(+) cells) and more pronounced overexpression of profibrotic genes for αSMA (2.0-fold), collagen I (6.8-fold), fibronectin (4.3-fold), CTGF (1.8-fold), and PAI-1 (3.8-fold), despite similar BMP-7 expression. Also, 1.3-fold more MFPCs were obtained from BMP-6 null than from WT mononuclear cell cultures, but in vivo only very few MFPCs were observed in obstructed kidneys, irrespective of BMP-6 genotype. The obstructed kidneys of BMP-6 null mice showed 2.2-fold more iron deposition, in association with 3.3-fold higher expression of the oxidative stress marker HO-1. Thus, ureteral obstruction leads to down-regulation of BMP-6 expression, and BMP-6 deficiency aggravates tubulointerstitial damage and fibrosis independent of BMP-7. This process appears to involve loss of both direct anti-inflammatory and antifibrotic action and indirect suppressive effects on renal iron deposition, oxidative stress, and MFPCs.

  4. Loss of Endogenous Bone Morphogenetic Protein-6 Aggravates Renal Fibrosis

    PubMed Central

    Dendooven, Amélie; van Oostrom, Olivia; van der Giezen, Dionne M.; Willem Leeuwis, Jan; Snijckers, Cristel; Joles, Jaap A.; Robertson, Elizabeth J.; Verhaar, Marianne C.; Nguyen, Tri Q.; Goldschmeding, Roel

    2011-01-01

    Bone morphogenetic protein-6 (BMP-6) suppresses inflammatory genes in renal proximal tubular cells and regulates iron metabolism by inducing hepcidin. In diabetic patients, an increase of myofibroblast progenitor cells (MFPCs), also known as fibrocytes, was found to be associated with decreased BMP-6 expression. We hypothesized that loss of endogenous BMP-6 would aggravate renal injury and fibrosis. Wild type (WT) and BMP-6 null mice underwent unilateral ureteral obstruction. In WT mice, ureteral obstruction down-regulated BMP-6. Obstructed kidneys of BMP-6 null mice showed more casts (1.5-fold), epithelial necrosis (1.4-fold), and brush border loss (1.3-fold). This was associated with more inflammation (1.8-fold more CD45+ cells) and more pronounced overexpression of profibrotic genes for αSMA (2.0-fold), collagen I (6.8-fold), fibronectin (4.3-fold), CTGF (1.8-fold), and PAI-1 (3.8-fold), despite similar BMP-7 expression. Also, 1.3-fold more MFPCs were obtained from BMP-6 null than from WT mononuclear cell cultures, but in vivo only very few MFPCs were observed in obstructed kidneys, irrespective of BMP-6 genotype. The obstructed kidneys of BMP-6 null mice showed 2.2-fold more iron deposition, in association with 3.3-fold higher expression of the oxidative stress marker HO-1. Thus, ureteral obstruction leads to down-regulation of BMP-6 expression, and BMP-6 deficiency aggravates tubulointerstitial damage and fibrosis independent of BMP-7. This process appears to involve loss of both direct anti-inflammatory and antifibrotic action and indirect suppressive effects on renal iron deposition, oxidative stress, and MFPCs. PMID:21356359

  5. Bone morphogenetic proteins differentially regulate pigmentation in human skin cells.

    PubMed

    Singh, Suman K; Abbas, Waqas A; Tobin, Desmond J

    2012-09-15

    Bone morphogenetic proteins (BMPs) are a large family of multi-functional secreted signalling molecules. Previously BMP2/4 were shown to inhibit skin pigmentation by downregulating tyrosinase expression and activity in epidermal melanocytes. However, a possible role for other BMP family members and their antagonists in melanogenesis has not yet been explored. In this study we show that BMP4 and BMP6, from two different BMP subclasses, and their antagonists noggin and sclerostin were variably expressed in melanocytes and keratinocytes in human skin. We further examined their involvement in melanogenesis and melanin transfer using fully matched primary cultures of adult human melanocytes and keratinocytes. BMP6 markedly stimulated melanogenesis by upregulating tyrosinase expression and activity, and also stimulated the formation of filopodia and Myosin-X expression in melanocytes, which was associated with increased melanosome transfer from melanocytes to keratinocytes. BMP4, by contrast, inhibited melanin synthesis and transfer to below baseline levels. These findings were confirmed using siRNA knockdown of BMP receptors BMPR1A/1B or of Myosin-X, as well as by incubating cells with the antagonists noggin and sclerostin. While BMP6 was found to use the p38MAPK pathway to regulate melanogenesis in human melanocytes independently of the Smad pathway, p38MAPK, PI3-K and Smad pathways were all involved in BMP6-mediated melanin transfer. This suggests that pigment formation may be regulated independently of pigment transfer. These data reveal a complex involvement of regulation of different members of the BMP family, their antagonists and inhibitory Smads, in melanocytes behaviour.

  6. Promotion of Bone Morphogenetic Protein Signaling by Tetraspanins and Glycosphingolipids

    PubMed Central

    Szymczak, Lindsey C.; Aydin, Taner; Yun, Sijung; Constas, Katharine; Schaeffer, Arielle; Ranjan, Sinthu; Kubba, Saad; Alam, Emad; McMahon, Devin E.; He, Jingpeng; Shwartz, Neta; Tian, Chenxi; Plavskin, Yevgeniy; Lindy, Amanda; Dad, Nimra Amir; Sheth, Sunny; Amin, Nirav M.; Zimmerman, Stephanie; Liu, Dennis; Schwarz, Erich M.; Smith, Harold; Krause, Michael W.; Liu, Jun

    2015-01-01

    Bone morphogenetic proteins (BMPs) belong to the transforming growth factor β (TGFβ) superfamily of secreted molecules. BMPs play essential roles in multiple developmental and homeostatic processes in metazoans. Malfunction of the BMP pathway can cause a variety of diseases in humans, including cancer, skeletal disorders and cardiovascular diseases. Identification of factors that ensure proper spatiotemporal control of BMP signaling is critical for understanding how this pathway is regulated. We have used a unique and sensitive genetic screen to identify the plasma membrane-localized tetraspanin TSP-21 as a key new factor in the C. elegans BMP-like “Sma/Mab” signaling pathway that controls body size and postembryonic M lineage development. We showed that TSP-21 acts in the signal-receiving cells and genetically functions at the ligand-receptor level. We further showed that TSP-21 can associate with itself and with two additional tetraspanins, TSP-12 and TSP-14, which also promote Sma/Mab signaling. TSP-12 and TSP-14 can also associate with SMA-6, the type I receptor of the Sma/Mab pathway. Finally, we found that glycosphingolipids, major components of the tetraspanin-enriched microdomains, are required for Sma/Mab signaling. Our findings suggest that the tetraspanin-enriched membrane microdomains are important for proper BMP signaling. As tetraspanins have emerged as diagnostic and prognostic markers for tumor progression, and TSP-21, TSP-12 and TSP-14 are all conserved in humans, we speculate that abnormal BMP signaling due to altered expression or function of certain tetraspanins may be a contributing factor to cancer development. PMID:25978409

  7. Bone

    NASA Astrophysics Data System (ADS)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  8. Protein malnutrition attenuates bone anabolic response to PTH in female rats.

    PubMed

    Ammann, P; Zacchetti, G; Gasser, J A; Lavet, C; Rizzoli, R

    2015-02-01

    PTH is indicated for the treatment of severe osteoporosis. Elderly osteoporotic patients frequently suffer from protein malnutrition, which may contribute to bone loss. It is unknown whether this malnutrition may affect the response to PTH. Therefore, the aim of the present study was to assess whether an isocaloric low-protein (LP) diet may influence the bone anabolic response to intermittent PTH in 6-month-old female rats. Six-month-old female rats were either pair fed an isocaloric LP diet (2.5% casein) or a normal-protein (NP) diet (15% casein) for 2 weeks. The rats continued on their respective diet while being treated with 5- or 40-μg/kg recombinant human PTH amino-terminal fragment 1-34 (PTH-[1-34]) daily, or with vehicle for 4 weeks. At the end of this period, areal bone mineral density, bone mineral content, microstructure, and bone strength in axial compression of proximal tibia or 3-point bending for midshaft tibia tests were measured. Blood was collected for the determination of IGF-I and osteocalcin. After 4 weeks of PTH-(1-34), the dose-dependent increase of proximal tibia bone mineral density, trabecular microstructure variables, and bone strength was attenuated in rats fed a LP diet as compared with rats on a NP intake. At the level of midshaft tibia cortical bone, PTH-(1-34) exerted an anabolic effect only in the NP but not in the LP diet group. Protein malnutrition was associated with lower IGF-I levels. Protein malnutrition attenuates the bone anabolic effects of PTH-(1-34) in rats. These results suggest that a sufficient protein intake should be recommended for osteoporotic patients undergoing PTH therapy.

  9. Infrared laser light further improves bone healing when associated with bone morphogenetic proteins and guided bone regeneration: an in vivo study in a rodent model.

    PubMed

    Pinheiro, Antonio Luiz B; Martinez Gerbi, Marleny E; Carneiro Ponzi, Elizabeth Arruda; Pedreira Ramalho, Luciana Maria; Marques, Aparecida M C; Carvalho, Carolina Montagn; Santos, Rafael de Carneiro; Oliveira, Priscila Chagas; Nóia, Manuela

    2008-04-01

    This study assessed histologically the effect of laser photobiomodulation on the repair of surgical defects created in the femurs of Wistar rats treated or not treated with bone morphogenetic proteins (BMPs) and organic bovine bone graft. This paper is part of an ongoing series of works in which biomaterials and/or guided bone regeneration (GBR) are used in association with laser photobiomodulation. Several previous reports from our group have shown that the use of laser photobiomodulation improves the treatment of bone defects. Forty-eight adult male Wistar rats were divided into four randomized groups: group 1 (controls, n = 12); group 2 (laser photobiomodulation, n = 12); group 3 (BMPs + organic bovine bone graft + GBR, n = 12); and group 4 (BMPs + organic bovine bone graft + GBR + laser photobiomodulation, n = 12). The irradiated groups received seven irradiations every 48 h, the first immediately after the surgical procedure. Laser photobiomodulation (830 nm, 40 mW, CW, phi approximately 0.6 mm) consisted of a total of 16 J/cm2 per session at four points (4 J/cm2 each) equally spaced around the periphery of the defect. The animals were sacrificed after 15, 21, and 30 d, and the specimens were routinely embedded in wax and stained with hematoxylin and eosin and Sirius red stains and analyzed under light microscopy. The results showed histological evidence of increased deposition of collagen fibers (at 15 and 21 d), as well as an increased amount of well-organized bone trabeculi at the end of the experimental period (30 d) in irradiated animals compared to non-irradiated controls. We concluded that the use of laser photobiomodulation in association with BMPs, organic bovine bone grafts, and GBR increases the positive biomodulating effects of laser energy.

  10. Effect of Autologous Bone Marrow Stromal Cell Seeding and Bone Morphogenetic Protein-2 Delivery on Ectopic Bone Formation in a Microsphere/Poly(Propylene Fumarate) Composite

    PubMed Central

    Kempen, Diederik H.R.; Kruyt, Moyo C.; Lu, Lichun; Wilson, Clayton E.; Florschutz, Anthony V.; Yaszemski, Michael J.; Dhert, Wouter J.A.

    2009-01-01

    A biodegradable microsphere/scaffold composite based on the synthetic polymer poly(propylene fumarate) (PPF) holds promise as a scaffold for cell growth and sustained delivery vehicle for growth factors for bone regeneration. The objective of the current work was to investigate the in vitro release and in vivo bone forming capacity of this microsphere/scaffold composite containing bone morphogenetic protein-2 (BMP-2) in combination with autologous bone marrow stromal cells (BMSCs) in a goat ectopic implantation model. Three composites consisting of 0, 0.08, or 8 μg BMP-2 per mg of poly(lactic-co-glycolic acid) microspheres, embedded in a porous PPF scaffold, were combined with either plasma (no cells) or culture-expanded BMSCs. PPF scaffolds impregnated with a BMP-2 solution and combined with BMSCs as well as empty PPF scaffolds were also tested. The eight different composites were implanted subcutaneously in the dorsal thoracolumbar area of goats. Incorporation of BMP-2–loaded microspheres in the PPF scaffold resulted in a more sustained in vitro release with a lower burst phase, as compared to BMP-2–impregnated scaffolds. Histological analysis after 9 weeks of implantation showed bone formation in the pores of 11/16 composites containing 8 μg/mg BMP-2–loaded microspheres with no significant difference between composites with or without BMSCs (6/8 and 5/8, respectively). Bone formation was also observed in 1/8 of the BMP-2–impregnated scaffolds. No bone formation was observed in the other conditions. Overall, this study shows the feasibility of bone induction by BMP-2 release from microspheres/scaffold composites. PMID:18925831

  11. Increase in bone protein components with healing rat fractures: enhancement by zinc treatment.

    PubMed

    Igarashi, A; Yamaguchi, M

    1999-12-01

    The alteration in bone components in the femoral-diaphyseal tissues with fracture healing was investigated. Rats were sacrificed 7 and 14 days after the femoral fracture. Protein content in the femoral-diaphyseal tissues was markedly elevated by fracture healing. Analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that many protein molecules were induced in the diaphyseal tissues with fracture healing. Moreover, when the femoral-diaphyseal tissues with fracture healing were cultured for 24 and 48 h in a serum-free medium, many proteins in the bone tissues were released into the medium. Also, the culture of the diaphyseal tissues with fracture healing caused a significant increase in bone alkaline phosphatase activity and deoxyribonucleic acid (DNA) content. Meanwhile, the presence of zinc acexamate (10-5 and 10-4 M), a stimulator of bone formation, in a culture medium induced a significant elevation of protein content and alkaline phosphatase activity in the diaphyseal tissues with fracture healing. Such an effect was completely abolished by the presence of cycloheximide (10-6 M), an inhibitor of protein synthesis. The present study suggests that fracture healing induces a newly synthesized bone protein component including stimulatory factor(s) for bone formation. Zinc supplementation may stimulate the healing of femoral fracture.

  12. Bone morphogenetic proteins and their antagonists: current and emerging clinical uses

    PubMed Central

    Ali, Imran H A; Brazil, Derek P

    2014-01-01

    Bone morphogenetic proteins (BMPs) are members of the TGFβ superfamily of secreted cysteine knot proteins that includes TGFβ1, nodal, activins and inhibins. BMPs were first discovered by Urist in the 1960s when he showed that implantation of demineralized bone into intramuscular tissue of rabbits induced bone and cartilage formation. Since this seminal discovery, BMPs have also been shown to play key roles in several other biological processes, including limb, kidney, skin, hair and neuronal development, as well as maintaining vascular homeostasis. The multifunctional effects of BMPs make them attractive targets for the treatment of several pathologies, including bone disorders, kidney and lung fibrosis, and cancer. This review will summarize current knowledge on the BMP signalling pathway and critically evaluate the potential of recombinant BMPs as pharmacological agents for the treatment of bone repair and tissue fibrosis in patients. PMID:24758361

  13. Analysis of relevant proteins from bone graft harvested using the reamer irrigator and aspirator system (RIA) versus iliac crest (IC) bone graft and RIA waste water.

    PubMed

    Crist, Brett D; Stoker, Aaron M; Stannard, James P; Cook, James L

    2016-08-01

    Femoral reaming using a Reamer Irrigator Aspirator (RIA) can produce greater than three liters of waste water per procedure, which contains cells and proteins that could promote bone healing. This purpose of this study was to determine the protein profile of RIA waste water and compare protein synthesis by cells harvested via RIA versus iliac crest (IC) bone graft. Bone graft was collected from 30 patients-15 using RIA from the femur and 15 harvested from the iliac crest. Waste water collected during the RIA procedure was analyzed in 12 patients. Cells from each graft were cultured in monolayer using growth media for 14days and inductive media for the next 14days. Media samples were collected on days 14, 21, and 28. Proteins for analysis were chosen based on their potential in bone healing, pro-inflammatory, and anti-inflammatory processes. Proteins present in RIA waste water indicate the potential for clinical use of this filtrate as an adjunct for enhancing bone production, healing, and remodeling. Similarly, cells cultured from RIA bone graft harvests compared favorably to those from iliac crest bone grafts with respect to their potential to aid in bone healing. RIA waste water has potential to serve as an autogenic and allogenic enhancer for bone healing. Continued development of processing protocols for viable commercial use of the waste water and pre-clinical studies designed to evaluate RIA waste water products for bone healing are ongoing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. An atlas of gene regulatory networks reveals multiple three-gene mechanisms for interpreting morphogen gradients

    PubMed Central

    Cotterell, James; Sharpe, James

    2010-01-01

    The interpretation of morphogen gradients is a pivotal concept in developmental biology, and several mechanisms have been proposed to explain how gene regulatory networks (GRNs) achieve concentration-dependent responses. However, the number of different mechanisms that may exist for cells to interpret morphogens, and the importance of design features such as feedback or local cell–cell communication, is unclear. A complete understanding of such systems will require going beyond a case-by-case analysis of real morphogen interpretation mechanisms and mapping out a complete GRN ‘design space.' Here, we generate a first atlas of design space for GRNs capable of patterning a homogeneous field of cells into discrete gene expression domains by interpreting a fixed morphogen gradient. We uncover multiple very distinct mechanisms distributed discretely across the atlas, thereby expanding the repertoire of morphogen interpretation network motifs. Analyzing this diverse collection of mechanisms also allows us to predict that local cell–cell communication will rarely be responsible for the basic dose-dependent response of morphogen interpretation networks. PMID:21045819

  15. Staphylococcal protein A promotes osteoclastogenesis through MAPK signaling during bone infection.

    PubMed

    Wang, Yuan; Liu, Xin; Dou, Ce; Cao, Zhen; Liu, Chuan; Dong, Shiwu; Fei, Jun

    2017-09-01

    Bone infection is a common and serious complication in the orthopedics field, which often leads to excessive bone destruction and non-union. Osteoclast is the only type of cells which have the function of bone resorption. Its over activation is closely related to excessive bone loss. Staphylococcus aureus (S. aureus) is a major pathogen causing bone infection, which can produce a large number of strong pathogenic substances staphylococcal protein A (SPA). However, few studies were reported about the effects of SPA on osteoclastogenesis. In our study, we observed that S. aureus activated osteoclasts and promoted bone loss in bone infection specimens. Then, we investigated the effects of SPA on RANKL-induced osteoclastogenesis in vitro, the results revealed that SPA promoted osteoclastic differentiation and fusion, and enhanced osteoclastic bone resorption. In addition, we also showed that SPA upregulated the expression of NFATc1 and c-FOS through the activation of MAPK signaling to promote osteoclastogenesis. Our findings might help us better understand the pathogenic role of S. aureus in bone infection and develop new therapeutic strategies for infectious bone diseases. © 2017 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.

  16. The reaction of the dura to bone morphogenetic protein (BMP) in repair of skull defects.

    PubMed Central

    Takagi, K; Urist, M R

    1982-01-01

    Trephine defects in the adult rat skull 0.8 cm in diameter, which do not spontaneously heal, were filled with a bovine bone morphogenetic protein (BMP) fraction. The defects healed not only by bony ingrowth from the trephine rim, but also by proliferation of pervascular mesenchymal-type cells (pericytes) of the dura mater. Under the influence of BMP, dural pericytes differentiated into chondroid and woven bone. Between three and four weeks postimplantation, sinusoids formed and the woven bone remodelled into lamellar bone. Concurrently, blood-borne bone marrow cells colonized the bone deposits, and the diploe were restored. Demonstrating that it is soluble in interstitial fluid, and diffusible across a nucleopore membrane (which isolated the bony margins of the skull), BMP induced new bone formation in the underlying dura and complete repair of the defect. The response of the dura to the BMP fraction produced more new bone than the response to allogeneic bone matrix. The BMP-induced repair was dose dependent; the quantity of new bone was proportional to the dose of the implanted BMP. Images Fig. 1a. Fig. 1b. Fig. 1c. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 8. Fig. 9. PMID:7092346

  17. The embryonic morphogen, Nodal, is associated with channel-like structures in human malignant melanoma xenografts.

    PubMed

    McAllister, Josephine C; Zhan, Qian; Weishaupt, Carsten; Hsu, Mei-Yu; Murphy, George F

    2010-04-01

    Formation of channel-like structures, also termed vasculogenic mimicry (VM), describes the ability of aggressive melanoma cells to form PAS-positive anastomosing structures that correlate with tumor virulence. This phenomenon may indicate differentiation plasticity, a feature melanoma cells may share with stem cells in the developing embryo. Recent studies have indicated that VM and tumorigenicity of human malignant melanoma may depend on the signaling pathways of an embryonic morphogen, Nodal. However, given the secretory nature of Nodal protein and melanoma cell heterogeneity, it remains unclear whether the Nodal-expressing cells participate directly or indirectly in VM that is potentially related to tumorigenic growth. We have developed a humanized murine xenograft model in which developing human melanomas may be sequentially studied during early stages of tumorigenic growth within a physiological human dermal microenvironment. Nodal protein localized diffusely to melanoma cell membranes, with occasional foci of accentuated reactivity in patterns suggestive of channel formation. Similar findings were detected in a limited number of patient-derived tumors. In situ hybridization confirmed Nodal mRNA to be restricted to tumor cells within xenografts that formed arborizing networks in patterns consistent with VM. These data indicate that Nodal gene expression is associated with formation of VM-like structures in a physiologically relevant model of human melanoma tumorigenesis, and further support a key role for Nodal expression in the formation of channel-like structures. The humanized xenograft model should be useful in future studies to define the mechanistic pathways responsible for VM and melanoma progression.

  18. Recombinant human bone morphogenetic protein-2 suspended in fibrin glue enhances bone formation during distraction osteogenesis in rabbits

    PubMed Central

    Li, Yunfeng; Li, Rui; Hu, Jing; Song, Donghui; Jiang, Xiaowen

    2016-01-01

    Introduction Bone morphogenetic protein-2 (BMP-2) has high potential for bone formation, but its in vivo effects are unpredictable due to the short life time. This study was designed to evaluate the effects of recombinant human (rh) BMP-2 suspended in fibrin on bone formation during distraction osteogenesis (DO) in rabbits. Material and methods The in vitro release kinetics of rhBMP-2 suspended in fibrin was tested using an enzyme-linked immunosorbent assay. Unilateral tibial lengthening for 10 mm was achieved in 48 rabbits. At the completion of osteodistraction, vehicle, fibrin, rhBMP-2 or rhBMP-2 suspended in fibrin (rhBMP-2 + fibrin) was injected into the center of the lengthened gap, with 12 animals in each group. Eight weeks later, the distracted callus was examined by histology, micro-CT and biomechanical testing. Radiographs of the distracted tibiae were taken at both 4 and 8 weeks after drug treatment. Results It was found that fibrin prolonged the life span of rhBMP-2 in vitro with sustained release during 17 days. The rhBMP-2 + fibrin treated animals showed the best results in bone mineral density, bone volume fraction, cortical bone thickness by micro-CT evaluation and mechanical properties by the three-point bending test when compared to the other groups (p < 0.05). In histological images, rhBMP-2 + fibrin treatment showed increased callus formation and better gap bridging compared to the other groups. Conclusions The results of this study suggest that fibrin holds promise to be a good carrier of rhBMP-2, and rhBMP-2 suspended in fibrin showed a stronger promoting effect on bone formation during DO in rabbits. PMID:27279839

  19. 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.

  20. Relative and combined effects of selenium, protein deficiency and ethanol on bone.

    PubMed

    González-Pérez, José María; González-Reimers, Emilio; Durán-Castellón, María del Carmen; Santolaria-Fernández, Franscisco; Galindo-Martín, Luis; RosVilamajó, Rosa; de la Vega-Prieto, María José; Viña-Rodríguez, Jose; Abreu-González, Pedro

    2011-04-01

    Some observations suggest that oxidative damage may affect both osteoblastic function and osteoclastic activity in alcohol-mediated bone alterations. Selenium, a potent antioxidant, is decreased in alcoholics. To analyse if the supplementation with selenium may alter bone changes observed in a murine model fed ethanol and/or a 2% protein-containing diet, following the Lieber-deCarli design. Adult male Sprague-Dawley rats were divided into 8 groups, which received the Lieber-DeCarli control diet, an isocaloric, 36% ethanol-containing diet, an isocaloric, 2% protein-containing diet; and an isocaloric diet containing 2% protein and 36% ethanol diet, and another similar four groups to which selenomethionine (1mg/kg body weight). After sacrifice (5 weeks later), trabecular bone mass was histomorphometrically assessed, bone and serum selenium were determined by flame atomic absorption spectrophotometry, and serum osteocalcin, insulin growth factor 1 (IGF-1), PTH and telopeptide, by radioimmunoanalysis. Liver glutathione peroxidase (GPX) activity was also determined. Ethanol-fed rats showed decreased TBM, IGF-1 and osteocalcin, especially when ethanol was added to a 2%-protein diet. Selenium did not modify at all bone parameters, despite a marked increase in serum selenium and a less pronounced one in bone selenium, and an increase in liver GPX. Our results do not support the existence of a beneficial effect of selenium addition on bone changes observed in this murine model treated following the Lieber-deCarli experimental design. Copyright © 2011 Elsevier GmbH. All rights reserved.

  1. Attenuated Human Bone Morphogenetic Protein-2–Mediated Bone Regeneration in a Rat Model of Composite Bone and Muscle Injury

    PubMed Central

    Li, Mon-Tzu A.; Uhrig, Brent A.; Boerckel, Joel David; Huebsch, Nathaniel; Lundgren, Taran L.; Warren, Gordon L.; Guldberg, Robert E.

    2013-01-01

    Extremity injuries involving large bone defects with concomitant severe muscle damage are a significant clinical challenge often requiring multiple treatment procedures and possible amputation. Even if limb salvage is achieved, patients are typically left with severe short- and long-term disabilities. Current preclinical animal models do not adequately mimic the severity, complexity, and loss of limb function characteristic of these composite injuries. The objectives of this study were to establish a composite injury model that combines a critically sized segmental bone defect with an adjacent volumetric muscle loss injury, and then use this model to quantitatively assess human bone morphogenetic protein-2 (rhBMP-2)–mediated tissue regeneration and restoration of limb function. Surgeries were performed on rats in three experimental groups: muscle injury (8-mm-diameter full-thickness defect in the quadriceps), bone injury (8-mm nonhealing defect in the femur), or composite injury combining the bone and muscle defects. Bone defects were treated with 2 μg of rhBMP-2 delivered in the pregelled alginate injected into a cylindrical perforated nanofiber mesh. Bone regeneration was quantitatively assessed using microcomputed tomography, and limb function was assessed using gait analysis and muscle strength measurements. At 12 weeks postsurgery, treated bone defects without volumetric muscle loss were consistently bridged. In contrast, the volume and mechanical strength of regenerated bone were attenuated by 45% and 58%, respectively, in the identically treated composite injury group. At the same time point, normalized muscle strength was reduced by 51% in the composite injury group compared to either single injury group. At 2 weeks, the gait function was impaired in all injury groups compared to baseline with the composite injury group displaying the greatest functional deficit. We conclude that sustained delivery of rhBMP-2 at a dose sufficient to induce bridging of

  2. Promotion of bone growth by dietary soy protein isolate: Comparision with dietary casein, whey hydrolysate and rice protein isolate in growing female rats

    USDA-ARS?s Scientific Manuscript database

    The effects of different dietary protein sources(casein (CAS), soy protein isolate (SPI), whey protein hydrolysate (WPH) and rice protein isolate (RPI)) on bone were studied in intact growing female rats and in ovarectomized (OVX) rats showing sex steroid deficiency-induced bone loss. In addition, S...

  3. Structural bone allograft combined with genetically engineered mesenchymal stem cells as a novel platform for bone tissue engineering.

    PubMed

    Xie, Chao; Reynolds, David; Awad, Hani; Rubery, Paul T; Pelled, Gadi; Gazit, Dan; Guldberg, Robert E; Schwarz, Edward M; O'Keefe, Regis J; Zhang, Xinping

    2007-03-01

    The presence of live periosteal progenitor cells on the surface of bone autografts confers better healing than devitalized allograft. We have previously demonstrated in a murine 4 mm segmental femoral bone-grafting model that live periosteum produces robust endochondral and intramembraneous bone formation that is essential for effective healing and neovascularization of structural bone grafts. To the end of engineering a live pseudo-periosteum that could induce a similar response onto devitalized bone allograft, we seeded a mesenchymal stem cell line stably transfected with human bone morphogenic protein-2/beta-galactosidase (C9) onto devitalized bone allografts or onto a membranous small intestinal submucosa scaffold that was wrapped around the allograft. Histology showed that C9-coated allografts displayed early cartilaginous tissue formation at day 7. By 6 and 9 weeks, a new cortical shell was found bridging the segmental defect that united the host bones. Biomechanical testing showed that C9-coated allografts displayed torsional strength and stiffness equivalent to intact femurs at 6 weeks and superior to live isografts at 9 weeks. Volumetric and histomorphometric micro-computed tomography analyses demonstrated a 2-fold increase in new bone formation around C9-coated allografts, which resulted in a substantial increase in polar moment of inertia (pMOI) due to the formation of new cortical shell around the allografts. Positive correlations between biomechanics and new bone volume and pMOI were found, suggesting that the biomechanical function of the grafted femur relates to both morphological parameters. C9-coated allograft also exhibited slower resorption of the graft cortex at 9 weeks than live isograft. Both new bone formation and the persistent allograft likely contributed to the improved biomechanics of C9-coated allograft. Taken together, we propose a novel strategy to combine structural bone allograft with genetically engineered mesenchymal stem cells as

  4. Physical growth and bone age of survivors of protein energy malnutrition.

    PubMed Central

    Alvear, J; Artaza, C; Vial, M; Guerrero, S; Muzzo, S

    1986-01-01

    Early postnatal malnutrition produces delay in growth and developmental processes, and children from a low socioeconomical level where undernutrition is prevalent are shorter than those from higher socioeconomic levels. We examined the effects of severe and early protein energy malnutrition on growth and bone maturation. We studied 40 preschool children who had been admitted to hospital in infancy with protein energy malnutrition and 38 children from the same socioeconomic level, paired for age and sex, who had never been malnourished. Growth measurements were made over a period of 4-6 years, and bone age was determined in a subgroup through wrist roentgenograms. Results showed a correlation between protein energy malnutrition, birth weight of infants, and mother's height and head circumference. The group with protein energy malnutrition showed a significant delay in stature after four years, especially the girls (p less than 0.001). Weight:height ratio was reduced in boys compared with controls but not in girls. Both groups showed a delay in bone maturation, but there were no significant differences between them. We found a positive correlation between bone age and arm fat area in control boys and between bone age and height for age in boys with protein energy malnutrition. The finding that rehabilitated children were shorter than the control group but had similar bone age at follow up suggests that genetic or prenatal factors were important in their later poor growth, and this suggestion is supported by their smaller birth size and the smaller size of their mothers. PMID:3083790

  5. Effects of chitosan-coated pressed calcium sulfate pellets combined with recombinant human bone morphogenetic protein 2 on bone formation in femoral condyle-contained bone defects.

    PubMed

    Chen, Hua; Cui, Xu; Yu, XueZhong; Tian, XueZhong; Zhang, BoXun; Tang, PeiFu; Wang, Yan

    2010-01-01

    Calcium sulfate has a rapid degradation rate and little osteoinductive capability. Chitosan-coated pressed calcium sulfate pellets combined with recombinant human bone morphogenetic protein 2 (rhBMP-2) have been developed that exhibit decreased resorption speed and increased compressive strength and osteoinduction. A rabbit femoral condyle-contained bone defect model was used to study the restoration of the defects treated with chitosan-coated pressed calcium sulfate pellets combined with rhBMP-2, chitosan-coated pressed calcium sulfate pellets, and uncoated pressed calcium sulfate pellets. No pellets were implanted in the control group. After 3 and 13 weeks, the results indicated that chitosan-coated pressed calcium sulfate pellets exhibited relatively slower resorption that closely coincides with the growth rate of new bone and enhanced osteogenesis when combined with rhBMP-2.

  6. Enhanced Control of In Vivo Bone Formation with Surface Functionalized Alginate Microbeads Incorporating Heparin and Human Bone Morphogenetic Protein-2

    PubMed Central

    Abbah, Sunny Akogwu; Liu, Jing; Goh, James Cho Hong

    2013-01-01

    In this study, we tested the hypothesis that a surface functionalization delivery platform incorporating heparin onto strontium alginate microbeads surfaces would convert this “naive carriers” into “mini-reservoirs” for localized in vivo delivery of recombinant human bone morphogenetic protein-2 (rhBMP-2) that will induce functional bone regeneration. In vitro evaluation confirmed that (1) heparin incorporation could immobilize and prolong rhBMP-2 release for approximately 3 weeks; (2) a significant decrease (p<0.01) in rhBMP-2 burst release is attainable depending on initial protein load; and (3) rhBMP-2 released from surface functionalized microbeads retained bioactivity and stimulated higher alkaline phosphatase activity in cultured C2C12 cells when compared with daily administration of fresh bolus rhBMP-2. Subsequently, surface functionalized microbeads were used for in vivo delivery of rhBMP-2 at local sites of posterolateral spinal fusion surgery in rats. The microbeads were loaded into the pores of medical-grade polyepsilone caprolactone-tricalcium phosphate scaffolds before implantation. Results revealed robust bone formation and a biomechanically solid fusion after 6 weeks. When compared with a control group consisting of an equivalent amount of rhBMP-2 that was directly adsorbed onto bare-surfaced microbeads with no heparin, a 5.3-fold increase in bone volume fraction and a 2.6-fold increase in bending stiffness (flexion/extension) were observed. When compared with collagen sponge carriers of rhBMP-2, a 1.5-fold and a 1.3-fold increase in bone volume fraction and bending stiffness were observed, respectively. More importantly, 3D micro-computed tomography images enabled the visualization of a well-contained newly formed bone at ipsilateral implant sites with surface functionalized rhBMP-2 delivery. This was absent with collagen sponge carriers where newly formed bone tissue was poorly contained and crossed over the posterior midline to

  7. Regulation of bone formation and remodeling by G-protein-coupled receptor 48.

    PubMed

    Luo, Jian; Zhou, Wei; Zhou, Xin; Li, Dali; Weng, Jinsheng; Yi, Zhengfang; Cho, Sung Gook; Li, Chenghai; Yi, Tingfang; Wu, Xiushan; Li, Xiao-Ying; de Crombrugghe, Benoit; Höök, Magnus; Liu, Mingyao

    2009-08-01

    G-protein-coupled receptor (GPCR) 48 (Gpr48; Lgr4), a newly discovered member of the glycoprotein hormone receptor subfamily of GPCRs, is an orphan GPCR of unknown function. Using a knockout mouse model, we have characterized the essential roles of Gpr48 in bone formation and remodeling. Deletion of Gpr48 in mice results in a dramatic delay in osteoblast differentiation and mineralization, but not in chondrocyte proliferation and maturation, during embryonic bone formation. Postnatal bone remodeling is also significantly affected in Gpr48(-/-) mice, including the kinetic indices of bone formation rate, bone mineral density and osteoid formation, whereas the activity and number of osteoclasts are increased as assessed by tartrate-resistant acid phosphatase staining. Examination of the molecular mechanism of Gpr48 action in bone formation revealed that Gpr48 can activate the cAMP-PKA-CREB signaling pathway to regulate the expression level of Atf4 in osteoblasts. Furthermore, we show that Gpr48 significantly downregulates the expression levels of Atf4 target genes/proteins, such as osteocalcin (Ocn; Bglap2), bone sialoprotein (Bsp; Ibsp) and collagen. Together, our data demonstrate that Gpr48 regulates bone formation and remodeling through the cAMP-PKA-Atf4 signaling pathway.

  8. Inflammatory Bowel Disease in a Rodent Model Alters Osteocyte Protein Levels Controlling Bone Turnover.

    PubMed

    Metzger, Corinne E; Narayanan, Anand; Zawieja, David C; Bloomfield, Susan A

    2017-04-01

    Bone loss is a common comorbidity of inflammatory bowel disease (IBD), leading to elevated fracture risk in these patients. Inflammatory factors associated with IBD cause increased bone resorption and decreased bone formation with multiple factors implicated as instigators of these alterations. In this project, we examined the influence of IBD on osteocyte proteins in male rats (2 months old) divided into two groups: induced gut inflammation via 2,4,6-trinitrobenzenesulfonic acid (TNBS) enema, and vehicle control. We examined the prevalence of two pro-inflammatory cytokines, tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), an anti-inflammatory cytokine, interleukin-10 (IL-10), the anabolic factor insulin-like growth factor-I (IGF-I), osteoclastogenesis regulators RANKL and OPG, and the bone formation inhibitor sclerostin in osteocytes in three bone compartments 4 weeks after initiation of gut inflammation. Histomorphometry of the proximal tibia and fourth lumbar vertebra revealed lower bone volume, lower bone formation rate (BFR), lower osteoid surface (OS), and higher osteoclast surface (Oc.S) with TNBS. Tibial mid-shaft periosteal BFR was also lower with TNBS. Immunohistochemical staining of the distal femur demonstrated that %TNF-α(+) , %IL-6(+) , %RANKL(+) , and %OPG(+) osteocytes were elevated in cancellous bone in TNBS animals compared to vehicle. These changes were coincident with increased bone resorption. With regression analysis, %RANKL(+) osteocytes statistically predicted the increase in cancellous Oc.S (R(2)  = 0.565). Increased %sclerostin(+) osteocytes observed in the TNBS treatment predicted declines in cancellous OS (R(2)  = 0.581) as well as BFR in cancellous and cortical bone (R(2)  = 0.674, R(2)  = 0.908, respectively). Contrary to our hypothesis, %IGF-I(+) osteocytes increased in TNBS animals. In conclusion, the IBD model produced a systemic inflammation that altered the regulatory protein profile in osteocytes that

  9. Coordinated regulation of dorsal bone morphogenetic protein 4 and ventral Sonic hedgehog signaling specifies the dorso-ventral polarity in the optic vesicle and governs ocular morphogenesis through fibroblast growth factor 8 upregulation.

    PubMed

    Kobayashi, Takuma; Yasuda, Kunio; Araki, Masasuke

    2010-05-01

    Dorsal and ventral specification in the early optic vesicle plays a crucial role in vertebrate ocular morphogenesis, and proper dorsal-ventral polarity in the optic vesicle ensures that distinct structures develop in separate domains within the eye primordium. The polarity is determined progressively during development by coordinated regulation of extraocular dorsal and ventral factors. In the present study, we cultured discrete portions of embryonic chick brains by preparing anterior cephalon, anterior dorsal cephalon and anterior ventral cephalon, and clearly demonstrate that bone morphogenetic protein 4 (BMP4) and Sonic hedgehog (Shh) constitute a dorsal-ventral signaling system together with fibroblast growth factor 8 (FGF8). BMP4 and Shh upregulate Tbx5 and Pax2, as reported previously, and at the same time Shh downregulates Tbx5, while BMP4 affects Pax2 expression to downregulate similarly. Shh induces Fgf8 expression in the ventral optic vesicle. This, in turn, determines the distinct boundary of the retinal pigmented epithelium and the neural retina by suppressing Mitf expression. The lens develops only when signals from both the dorsal and ventral regions come across together. Inverted deposition of Shh and BMP4 signals in organ-cultured optic vesicle completely re-organized ocular structures to be inverted. Based on these observations we propose a novel model in which the two signals govern the whole of ocular development when they encounter each other in the ocular morphogenic domain.

  10. Surface-associated proteins from Staphylococcus aureus demonstrate potent bone resorbing activity.

    PubMed

    Nair, S; Song, Y; Meghji, S; Reddi, K; Harris, M; Ross, A; Poole, S; Wilson, M; Henderson, B

    1995-05-01

    Staphylococcus aureus infections are associated with rapid bone destruction in conditions such as osteomyelitis, bacterial arthritis, and infected orthopedic implant failure. How this bacterium induces bone destruction has not been defined. In studies of the role of oral Gram-negative bacteria in periodontal pathology, we have established that cell surface-associated proteins (SAPs) are potent stimulators of bone resorption. The surface-associated components from S. aureus have now been isolated and demonstrated to be extremely potent stimulators of bone resorption in the murine calvarial bone resorption assay. Bone resorption appears to be due to proteins, is not the result of contamination with lipoteichoic acid or muramyl dipeptide, and is potently inhibited by indomethacin and can be completely blocked by high concentrations of interleukin-1 receptor antagonist or TN3-19.12, a neutralizing monoclonal antibody to murine TNF. The SAP fraction can stimulate fibroblasts or monocytes to release osteolytic cytokines, but only at high concentrations. Fractionation of the SAPs by high performance liquid chromatography demonstrated that a number of fractions were osteolytically active. The most active contained a heterodimeric protein of molecular weight 32-36 kD. The presence of this osteolytically active surface-associated fraction may account for the bone resorption associated with local infection with S. aureus.

  11. Recombinant Human Bone Morphogenetic Protein-2 in Debridement and Impacted Bone Graft for the Treatment of Femoral Head Osteonecrosis

    PubMed Central

    Gao, Fuqiang; Shi, Zhencai; Zhang, Qidong; Guo, Wanshou

    2014-01-01

    The purpose of this study was to compare the clinical outcomes of impacted bone graft with or without recombinant human bone morphogenetic protein-2 (rhBMP-2) for osteonecrosis of the femoral head (ONFH). We examined the effect of bone-grafting through a window at the femoral head-neck junction, known as the “light bulb” approach, for the treatment of ONFH with a combination of artificial bone (Novobone) mixed with or without rhBMP-2. A total of 42 patients (72 hips) were followed-up from 5 to 7.67 years (average of 6.1 years). The patients with and without BMP were the first group (IBG+rhBMP-2) and the second group (IBG), respectively. The clinical effectiveness was evaluated by Harris hip score (HHS). The radiographic follow-up was evaluated by pre-and postoperative X-ray and CT scan. Excellent, good, and fair functions were obtained in 36, 12, and 7 hips, respectively. The survival rate was 81.8% and 71.8% in the first and second group, respectively. However, the survival rate was 90.3% in ARCO stage IIb, c, and only 34.6% in ARCO stage IIIa(P<0.05). It was concluded that good and excellent mid-term follow-up could be achieved in selected patients with ONFH treated with impacted bone graft operation. The rhBMP-2 might improve the clinical efficacy and quality of bone repair. PMID:24956102

  12. The effect of bovine whey protein on ectopic bone formation in young growing rats.

    PubMed

    Kelly, Owen; Cusack, Siobhan; Cashman, Kevin D

    2003-09-01

    The beneficial effect of bovine whey protein (WP) on bone metabolism has been shown in adult human subjects and ovariectomised rats. However, its effect on bone formation in earlier life, particularly during periods of bone mineral accrual, has not been investigated. Twenty-one male rats (4 weeks old, Wistar strain) were randomised by weight into three groups of seven rats each and fed ad libitum on a semi-purified low-Ca diet (3.0 g Ca/kg diet) containing 0 (control), 10 (diet WP1) or 20 (diet WP2) g bovine WP/kg for 47 d. On day 34 of the dietary intervention, all rats had two gelatine capsules containing demineralised bone powder implanted subcutaneously in the thorax region (a well-established in vivo model of ectopic bone formation). At 14 d after implantation, alkaline phosphatase activity (reflective of bone formation) in the bone implants from animals fed WP1 and -2 diets was almost 2-fold (P<0.01) that of control animals. Insulin-like growth factor (IGF)-I mRNA levels were about 3-fold (P<0.05) higher in implants from animals fed the WP diets compared with those from control animals. Serum- and urine-based biomarkers of bone metabolism and bone mineral composition in intact femora were unaffected by WP supplementation. In conclusion, the present findings suggest that bovine WP can enhance the rate of ectopic bone formation in young growing rats fed a Ca-restricted diet. This effect may be mediated by an increased synthesis of IGF-I in growing bone. The effect of WP on bone formation warrants further investigation.

  13. CCN3 Protein Participates in Bone Regeneration as an Inhibitory Factor*

    PubMed Central

    Matsushita, Yuki; Sakamoto, Kei; Tamamura, Yoshihiro; Shibata, Yasuaki; Minamizato, Tokutaro; Kihara, Tasuku; Ito, Masako; Katsube, Ken-ichi; Hiraoka, Shuichi; Koseki, Haruhiko; Harada, Kiyoshi; Yamaguchi, Akira

    2013-01-01

    CCN3, a member of the CCN protein family, inhibits osteoblast differentiation in vitro. However, the role of CCN3 in bone regeneration has not been well elucidated. In this study, we investigated the role of CCN3 in bone regeneration. We identified the Ccn3 gene by microarray analysis as a highly expressed gene at the early phase of bone regeneration in a mouse bone regeneration model. We confirmed the up-regulation of Ccn3 at the early phase of bone regeneration by RT-PCR, Western blot, and immunofluorescence analyses. Ccn3 transgenic mice, in which Ccn3 expression was driven by 2.3-kb Col1a1 promoter, showed osteopenia compared with wild-type mice, but Ccn3 knock-out mice showed no skeletal changes compared with wild-type mice. We analyzed the bone regeneration process in Ccn3 transgenic mice and Ccn3 knock-out mice by microcomputed tomography and histological analyses. Bone regeneration in Ccn3 knock-out mice was accelerated compared with that in wild-type mice. The mRNA expression levels of osteoblast-related genes (Runx2, Sp7, Col1a1, Alpl, and Bglap) in Ccn3 knock-out mice were up-regulated earlier than those in wild-type mice, as demonstrated by RT-PCR. Bone regeneration in Ccn3 transgenic mice showed no significant changes compared with that in wild-type mice. Phosphorylation of Smad1/5 was highly up-regulated at bone regeneration sites in Ccn3 KO mice compared with wild-type mice. These results indicate that CCN3 is up-regulated in the early phase of bone regeneration and acts as a negative regulator for bone regeneration. This study may contribute to the development of new strategies for bone regeneration therapy. PMID:23653360

  14. Aggregation of a Distributed Source in Morphogen Gradient Formation

    PubMed Central

    Lander, A. D.; Nie, Q.; Vargas, B.; Wan, F. Y. M.

    2007-01-01

    In the development of a biological entity, ligands (such as Decapentaplegic (Dpp) along the anterior–posterior axis of the Drosophila wing imaginal disc) are synthesized at a localized source and transported away from the source for binding with cell surface receptors to form concentration gradients of ligand–receptor complexes for cell signaling. Generally speaking, activities such as diffusion and reversible binding with degradable receptors also take place in the region of ligand production. The effects of such morphogen activities in the region of localized distributed ligand source on the ligand–receptor concentration gradient in the entire biological entity have been modeled and analyzed as System F in [1]. In this paper, we deduce from System F, a related end source model (System A) in which the effects of the distributed ligand source is replaced by an idealized point stimulus at the border between the (posterior) chamber and the ligand production region that simulates the average effects of the ligand activities in the production zone. This aggregated end source model is shown to adequately reproduce the significant implications of System F and to contain the corresponding ad hoc point source model, System R of [2], as a special case. Because of its simpler mathematical structure and the absence of any limitation on the ligand synthesis rate for the existence of steady-state gradients, System A type models are expected to be used widely. An example of such application is the recent study of the inhibiting effects of the formation of nonsignaling ligand–nonreceptor complexes [3]. PMID:17372620

  15. Alveolar Bone Grafting in Cleft Patients from Bone Defect to Dental Implants

    PubMed Central

    Vuletić, Marko; Jokić, Dražen; Rebić, Jerko; Žabarović, Domagoj; Macan, Darko

    2014-01-01

    Cleft lip and palate is the most common congenital deformity affecting craniofacial structures. Orofacial clefts have great impact on the quality of life which includes aesthetics, function, psychological impact, dental development and facial growth. Incomplete fusion of facial prominences during the fourth to tenth week of gestation is the main cause. Cleft gaps are closed with alveolar bone grafts in surgical procedure called osteoplasty. Autogenic bone is taken from the iliac crest as the gold standard. The time of grafting can be divided into two stages: primary and secondary. The alveolar defect is usually reconstructured between 7 and 11 years and is often related to the development of the maxillary canine root. After successful osteoplasty, cleft defect is closed but there is still a lack of tooth. The space closure with orthodontic treatment has 50-75% success. If the orthodontic treatment is not possible, in order to replace the missing tooth there are three possibilities: adhesive bridgework, tooth transplantation and implants. Dental implant has the role of holding dental prosthesis, prevents pronounced bone atrophy and loads the augmentation material in the cleft area. Despite the fact that autologous bone from iliac crest is the gold standard, it is not a perfect source for reconstruction of the alveolar cleft. Bone morphogenic protein (BMP) is appropriate as an alternative graft material. The purpose of this review is to explain morphology of cleft defects, historical perspective, surgical techniques and possibilities of implant and prosthodontic rehabilitation. PMID:27688373

  16. Acid diet (high meat protein) effects on calcium metabolism and bone health

    USDA-ARS?s Scientific Manuscript database

    Purpose of review: Update recent advancements regarding the effect of high animal protein on calcium utilization and bone health. Recent findings: Increased potential renal acid load resulting from a high protein (meat) intake has been closely associated with increased urinary calcium excretion. How...

  17. Cilia/Ift protein and motor -related bone diseases and mouse models.

    PubMed

    Yuan, Xue; Yang, Shuying

    2015-01-01

    Primary cilia are essential cellular organelles projecting from the cell surface to sense and transduce developmental signaling. They are tiny but have complicated structures containing microtubule (MT)-based internal structures (the axoneme) and mother centriole formed basal body. Intraflagellar transport (Ift) operated by Ift proteins and motors are indispensable for cilia formation and function. Mutations in Ift proteins or Ift motors cause various human diseases, some of which have severe bone defects. Over the last few decades, major advances have occurred in understanding the roles of these proteins and cilia in bone development and remodeling by examining cilia/Ift protein-related human diseases and establishing mouse transgenic models. In this review, we describe current advances in the understanding of the cilia/Ift structure and function. We further summarize cilia/Ift-related human diseases and current mouse models with an emphasis on bone-related phenotypes, cilia morphology, and signaling pathways.

  18. Cilia/Ift protein and motor-related bone diseases and mouse models

    PubMed Central

    Yuan, Xue; Yang, Shuying

    2015-01-01

    Primary cilia are essential cellular organelles projecting from the cell surface to sense and transduce developmental signaling. They are tiny but have complicated structures containing microtubule (MT)-based internal structures (the axoneme) and mother centriole formed basal body. Intraflagellar transport (Ift) operated by Ift proteins and motors are indispensable for cilia formation and function. Mutations in Ift proteins or Ift motors cause various human diseases, some of which have severe bone defects. Over the last few decades, major advances have occurred in understanding the roles of these proteins and cilia in bone development and remodeling by examining cilia/Ift protein-related human diseases and establishing mouse transgenic models. In this review, we describe current advances in the understanding of the cilia/Ift structure and function. We further summarize cilia/Ift-related human diseases and current mouse models with an emphasis on bone-related phenotypes, cilia morphology, and signaling pathways. PMID:25553465

  19. 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.

  20. Sandcastle Worm-Inspired Blood-Resistant Bone Graft Binder Using a Sticky Mussel Protein for Augmented In Vivo Bone Regeneration.

    PubMed

    Kim, Hyo Jeong; Choi, Bong-Hyuk; Jun, Sang Ho; Cha, Hyung Joon

    2016-12-01

    Xenogenic bone substitutes are commonly used during orthopedic reconstructive procedures to assist bone regeneration. However, huge amounts of blood accompanied with massive bone loss usually increase the difficulty of placing the xenograft into the bony defect. Additionally, the lack of an organic matrix leads to a decrease in the mechanical strength of the bone-grafted site. For effective bone grafting, this study aims at developing a mussel adhesion-employed bone graft binder with great blood-resistance and enhanced mechanical properties. The distinguishing water (or blood) resistance of the binder originates from sandcastle worm-inspired complex coacervation using negatively charged hyaluronic acid (HA) and a positively charged recombinant mussel adhesive protein (rMAP) containing tyrosine residues. The rMAP/HA coacervate stabilizes the agglomerated bone graft in the presence of blood. Moreover, the rMAP/HA composite binder enhances the mechanical and hemostatic properties of the bone graft agglomerate. These outstanding features improve the osteoconductivity of the agglomerate and subsequently promote in vivo bone regeneration. Thus, the blood-resistant coacervated mussel protein glue is a promising binding material for effective bone grafting and can be successfully expanded to general bone tissue engineering.

  1. Immature muscular tissue differentiation into bone-like tissue by bone morphogenetic proteins in vitro, with ossification potential in vivo.

    PubMed

    Hayashi, Tatsuhide; Kobayashi, Syuichiro; Asakura, Masaki; Kawase, Mayu; Ueno, Atsuko; Uematsu, Yasuaki; Kawai, Tatsushi

    2014-09-01

    The objective of this study was to induce bone formation from immature muscular tissue (IMT) in vitro, using bone morphogenetic proteins (BMPs) as a cytokine source and an expanded polytetrafluoroethylene (ePTFE) scaffold. In addition, cultured IMTs were implanted subcutaneously into Sprague-Dawley (SD) rats to determine their in vivo ossification potential. BMPs, extracted from bovine cortical bones, were applied to embryonic SD rat IMT cultures, before 2 weeks culture on ePTFE scaffolds. Osteoblast-like cells and osteoid tissues were partially identified by hematoxylin-eosin staining 2 weeks after culture. Collagen type I (Col-I), osteopontin (OP), and osteocalcin (OC) were detected in the osteoid tissues by immunohistochemical staining. OC gene expression remained low, but OP and Col-I were upregulated during the culture period. In vivo implanted IMTs showed slight radiopacity 1 week after implantation and strong radiopacity 2 and 3 weeks after implantation. One week after implantation, migration of numerous capillaries was observed and ossification was detected after 2 weeks by histological observation. These results suggest that IMTs are able to differentiate into bone-like tissue in vitro, with an ossification potential after implantation in vivo.

  2. CONNEXIN 43 AND BONE: NOT JUST A GAP JUNCTION PROTEIN

    PubMed Central

    Plotkin, Lilian I.

    2012-01-01

    Connexins are essential for the communication of cells among themselves and with their environment. Connexin hexamers assemble at the plasma membrane to form hemichannels that allow the exchange of cellular contents with the extracellular milieu. In addition, hemichannels expressed in neighboring cells align to form gap junction channels that mediate the exchange of contents among cells. Connexin 43 (Cx43) is the most abundant connexin expressed in bone cells and its deletion in all tissues leads to osteoblast dysfunction, as evidenced by reduced expression of osteoblast markers and delayed ossification. Moreover, Cx43 is essential for the survival of osteocytes; and mice lacking Cx43 in these cells exhibit increased prevalence of osteocyte apoptosis and empty lacunae in cortical bone. Work of several groups for the past few years has unveiled the role of Cx43 on the response of bone cells to a variety of stimuli. Thus, the preservation of the viability of osteoblasts and osteocytes by the anti-osteoporotic drugs bisphosphonates depends on Cx43 expression in vitro and in vivo. This survival effect does not require cell-to-cell communication and is mediated by unopposed hemichannels. Cx43 hemichannels are also required for the release of prostaglandins and ATP by osteocytes induced by mechanical stimulation in vitro. More recent evidence showed that the cAMP-mediated survival effect of parathyroid hormone (PTH) also requires Cx43 expression. Moreover, the hormone does not increase bone mineral content in mice haploinsufficient for Cx43 or lacking Cx43 in osteoblastic cells. Since inhibition of osteoblast apoptosis contributes, at least in part, to bone anabolism by PTH, the lack of response to the hormone might be due to the requirement of Cx43 for the effect of PTH on osteoblast survival. In summary, mounting evidence indicate that Cx43 is a key component of the intracellular machinery responsible for the transduction of signals in the skeleton in response to

  3. Physiology of bone: Mineral compartment proteins as candidates for environmental perturbation by lead

    SciTech Connect

    Sauk, J.J.; Somerman, M.J. )

    1991-02-01

    Termine et al. first demonstrated that sequential dissociative extraction and fractionation procedures with protease inhibitors could provide a convenient approach for the study of mineral compartment constituents. The primary extraction regimen used 4 M guanidine HCl to remove most of the protein from the nonmineralized phase of bone. Subsequently, EDTA-guanidine was used to remove the mineral-phase components. These methods discriminate on the basis of physical-chemical association with a mineral phase rather than on the specific gene products of a particular cell. In the present discussion emphasis is directed at a group of divalent cation binding proteins isolated from the mineral compartment of bone. The localization, synthesis, and chemical characteristics of osteonectin, bone sialoproteins I and II, and bone acidic glycoprotein-75 are discussed and offered as possible sites for perturbation by the environment with lead exposure.

  4. Physiology of bone: mineral compartment proteins as candidates for environmental perturbation by lead.

    PubMed Central

    Sauk, J J; Somerman, M J

    1991-01-01

    Termine et al. first demonstrated that sequential dissociative extraction and fractionation procedures with protease inhibitors could provide a convenient approach for the study of mineral compartment constituents. The primary extraction regimen used 4 M guanidine HCl to remove most of the protein from the nonmineralized phase of bone. Subsequently, EDTA-guanidine was used to remove the mineral-phase components. These methods discriminate on the basis of physical-chemical association with a mineral phase rather than on the specific gene products of a particular cell. In the present discussion emphasis is directed at a group of divalent cation binding proteins isolated from the mineral compartment of bone. The localization, synthesis, and chemical characteristics of osteonectin, bone sialoproteins I and II, and bone acidic glycoprotein-75 are discussed and offered as possible sites for perturbation by the environment with lead exposure. Images FIGURE 1. FIGURE 2. FIGURE 2. FIGURE 2. FIGURE 3. FIGURE 3. FIGURE 3. FIGURE 3. PMID:2040255

  5. [The effect of bone morphogenetic protein-2 and osteoprotegerin in trans-sutural distraction osteogenesis].

    PubMed

    Yao, Yusheng; Huang, Hua; Chang, Shimin; Wang, Chengyue; Wang, Guijun

    2012-08-01

    To determine if locally administered bone morphogenetic protein-2 (BMP-2) and osteoprotegerin (OPG) improved osteogenesis and new bone formation by trans-sutural distraction osteogenesis. Twenty four dogs were divided into three groups randomly and received new internal trans-sutural distraction osteogenesis treatment. Five days after operation, infusion apparatus with double-tube was inserted to submucosa near the distracted zone to deliver controlled release agent of recombinant human bone morphogenetic protein-2/poly (lactic-co-glycolic acid)/fibrin sealant (rhBMP-2/PLGA/FS) in group A and group C. Recombinant human osteoprotegerin/fibrin sealant (rhOPG/ FS) was injected three weeks later in group B and group C. Histology staining and bone histomorphometry were used to measure the changes of maxillary bone sutura after distraction for 1, 2, 4 and 6 weeks. New bone formation observed in distracted zone showed a significant increase in group A and C. Transmission electron microscope showed the osteoblast and osteocyte were active with dilated rough endoplasmic reticulum and a large number of chondriosomes and Golgi complex. After distraction for 6 weeks, indexes of osteoblast of group A, B, and C were 38.5 +/- 7.7, 35.7 +/- 6.5, and 41.7 +/- 11.0, indexes of osteoclast (Ioc) were 5.9 +/- 1.0, 1.2 +/- 0.3, and 2.8 +/- 0.4, bone trabecula thicknesses were (38.36 +/- 13.28), (66.20 +/- 9.16), and (51.85 +/- 9.92) microm respectively. Increased bone density and decreased Ioc were found in group B and C. The new elastic distractor is effective in inducing new bone formation. BMP-2 and OPG combination acts synergistically, and leads to significant enhancement of bone formation and remodeling.

  6. 32k Da protein improve ovariectomy-induced bone loss in rats

    PubMed Central

    Zhou, Yingtang; Jiang, Shenhua; Chen, Jing; Wang, Tao; Jiang, DengZhao; Chen, Hui; Yu, Huan

    2013-01-01

    The objective of the present study was to systematically explore the effects of 32K Da protein (32KP) on postmenopausal osteoporosis. Eighty 3-mo-old female Sprague-Dawley rats were employed and randomly divided into one sham-operated group (SHAM) and five ovariectomy (OVX) subgroups as OVX (control), OVX with 17-ethinylestradiol (E2, 25 g/kg/day), OVX with 32KP of graded doses (50, 50, or 150 mg/kg/day). 32KP or E2 diet was fed on week 4 after operation, for 16 weeks. Bone mass, bone turnover and strength were evaluated by dual-energy X-ray absorptiometry (DEXA), biochemical markers and three-point bending test, respectively. Femur marrow cavity was observed by light microscopy via hematoxylin-eosin staining. It is observed that different dosage treatment of 32KP increased the body weight and prevented the loss of bone mass induced by OVX. The prevention effect against bone loss was presumably due to the altering of the rate of bone remodeling. The bone mineral density and bone calcium content in OVX rats were lower than that in the control group, suggesting that 32KP was able to prevent significant bone loss. In addition, the data from three point bending test and femur sections showed that 32KP treatment enhanced bone strength and reduced the marrow cavity of the femur in OVX rats. In the serum and urine assay, 32KP decreased urinary deoxypyridinoline and calcium concentrations; however, serum alkaline phosphatase activities were not inhibited. It suggested that amelioration of bone loss was changed via inhibition of bone reabsorption. Our findings indicated that 32KP might be a potential alternative drug for the prevention and treatment of postmenopausal osteoporosis. PMID:23924638

  7. Demineralized dentin matrix combined with recombinant human bone morphogenetic protein-2 in rabbit calvarial defects

    PubMed Central

    2016-01-01

    Objectives The aim of this study was to compare the osteogenic effects of demineralized dentin matrix (DDM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in rabbit calvarial defects with DDM and anorganic bovine bone (ABB) combined with rhBMP-2. Materials and Methods Four round defects with 8-mm diameters were created in each rabbit calvaria. Each defect was treated with one of the following: 1) DDM, 2) ABB/rhBMP-2, or 3) DDM/rhBMP-2. The rhBMP-2 was combined with DDM and ABB according to a stepwise dry and dip lyophilizing protocol. Histological and microcomputed tomography (µCT) analyses were performed to measure the amount of bone formation and bone volume after 2- and 8-week healing intervals. Results Upon histological observation at two weeks, the DDM and ABB/rhBMP-2 groups showed osteoconductive bone formation, while the DDM/rhBMP-2 group showed osteoconductive and osteoinductive bone formation. New bone formation was higher in DDM/rhBMP-2, DDM and ABB decreasing order. The amounts of bone formation were very similar at two weeks; however, at eight weeks, the DDM/rhBMP-2 group showed a two-fold greater amount of bone formation compared to the DDM and ABB/rhBMP-2 groups. The µCT analysis showed markedly increased bone volume in the DDM/rhBMP-2 group at eight weeks compared with that of the DDM group. Notably, there was a slight decrease in bone volume in the ABB/rhBMP-2 group at eight weeks. There were no significant differences among the DDM, ABB/rhBMP-2, and DDM/rhBMP-2 groups at two or eight weeks. Conclusion Within the limitations of this study, DDM appears to be a suitable carrier for rhBMP-2 in orthotopic sites. PMID:27162749

  8. Prolyl hydroxylase domain proteins regulate bone mass through their expression in osteoblasts.

    PubMed

    Zhu, Ke; Song, Pingping; Lai, Yumei; Liu, Chuanju; Xiao, Guozhi

    2016-12-05

    The roles of prolyl hydroxylase domain proteins (PHDs) in bone are incompletely understood. Here we deleted the expression of genes encoding PHD1, PHD2, and PHD3 in osteoblasts in mice by breeding the floxed Phd1-3 mice with Col1a1-Cre transgenic mice. Results showed that mice lacking PHD1-3 in osteoblasts (Phd1-3ob-/-) had increased bone mass. Bone parameters such as bone volume/tissue volume (BV/TV), trabecular number (Tb.N), and trabecular thickness (Tb.Th) were increased, while trabecular spacing (Tb.Sp) was decreased in Phd1-3ob-/- relative to wild-type (WT) femurs. In contrast, loss of PHD1-3 in osteoblasts did not alter cortical thickness (Cort.Th). The mineralization apposition rate (MAR) was increased in Phd1-3ob-/- bone compared to that of wild-type (WT) bone, demonstrating an enhancement of osteoblast function. Loss of PHD1-3 increased the number of osteoblast progenitors (CFU-OBs) in bone marrow cultures. Interestingly, deleting Phd1-3 genes in osteoblasts increased osteoclast formation in vitro and in bone.

  9. The effect of recombinant human osteogenic protein-1 (bone morphogenetic protein-7) impregnation on allografts in a canine intercalary bone defect.

    PubMed

    Cullinane, Dennis M; Lietman, Steven A; Inoue, Nozomu; Deitz, Luke W; Chao, Edmund Y S

    2002-11-01

    The utility of cortical allografts in repairing large bone defects is limited by their slow and incomplete incorporation into host bone. In order to determine the effects of recombinant human osteogenic protein-1 (rhOP-1) impregnation on allograft incorporation, we used a canine intercalary bone defect model. Bilateral resection of a 4 cm segment of the femoral diaphysis and reconstruction with structural bone allografts were performed. In one limb, the allograft was soaked in solution with rhOP-1 for 1 h before implantation. In the other limb, the allograft was soaked in the same solution without rhOP-1. Dynamic load-bearing, radiographic analysis, biomechanical testing, and histomorphometric analysis were conducted. Radiographic analysis showed significantly larger periosteal callus area in the rhOP-1 treated group at week 2. The rhOP-1 significantly increased allograft bone porosity and significantly increased the number of active osteons in the allografts. There were no significant differences between the rhOP-1 treated and non-treated allografts in load bearing and biomechanical analyses. These findings indicate that rhOP- I increases intercalary allograft remodeling without deleterious effects in mechanical and functional strength.

  10. Medea SUMOylation restricts the signaling range of the Dpp morphogen in the Drosophila embryo.

    PubMed

    Miles, Wayne O; Jaffray, Ellis; Campbell, Susan G; Takeda, Shugaku; Bayston, Laura J; Basu, Sanjay P; Li, Mingfa; Raftery, Laurel A; Ashe, Mark P; Hay, Ronald T; Ashe, Hilary L

    2008-09-15

    Morphogens are secreted signaling molecules that form concentration gradients and control cell fate in developing tissues. During development, it is essential that morphogen range is strictly regulated in order for correct cell type specification to occur. One of the best characterized morphogens is Drosophila Decapentaplegic (Dpp), a BMP signaling molecule that patterns the dorsal ectoderm of the embryo by activating the Mad and Medea (Med) transcription factors. We demonstrate that there is a spatial and temporal expansion of the expression patterns of Dpp target genes in SUMO pathway mutant embryos. We identify Med as the primary SUMOylation target in the Dpp pathway, and show that failure to SUMOylate Med leads to the increased Dpp signaling range observed in the SUMO pathway mutant embryos. Med is SUMO modified in the nucleus, and we provide evidence that SUMOylation triggers Med nuclear export. Hence, Med SUMOylation provides a mechanism by which nuclei can continue to monitor the presence of extracellular Dpp signal to activate target gene expression for an appropriate duration. Overall, our results identify an unusual strategy for regulating morphogen range that, rather than impacting on the morphogen itself, targets an intracellular transducer.

  11. Caenorhabditis elegans SMA-10/LRIG is a conserved transmembrane protein that enhances bone morphogenetic protein signaling.

    PubMed

    Gumienny, Tina L; Macneil, Lesley; Zimmerman, Cole M; Wang, Huang; Chin, Lena; Wrana, Jeffrey L; Padgett, Richard W

    2010-05-20

    Bone morphogenetic protein (BMP) pathways control an array of developmental and homeostatic events, and must themselves be exquisitely controlled. Here, we identify Caenorhabditis elegans SMA-10 as a positive extracellular regulator of BMP-like receptor signaling. SMA-10 acts genetically in a BMP-like (Sma/Mab) pathway between the ligand DBL-1 and its receptors SMA-6 and DAF-4. We cloned sma-10 and show that it has fifteen leucine-rich repeats and three immunoglobulin-like domains, hallmarks of an LRIG subfamily of transmembrane proteins. SMA-10 is required in the hypodermis, where the core Sma/Mab signaling components function. We demonstrate functional conservation of LRIGs by rescuing sma-10(lf) animals with the Drosophila ortholog lambik, showing that SMA-10 physically binds the DBL-1 receptors SMA-6 and DAF-4 and enhances signaling in vitro. This interaction is evolutionarily conserved, evidenced by LRIG1 binding to vertebrate receptors. We propose a new role for LRIG family members: the positive regulation of BMP signaling by binding both Type I and Type II receptors.

  12. Caenorhabditis elegans SMA-10/LRIG Is a Conserved Transmembrane Protein that Enhances Bone Morphogenetic Protein Signaling

    PubMed Central

    Gumienny, Tina L.; MacNeil, Lesley; Zimmerman, Cole M.; Wang, Huang; Chin, Lena; Wrana, Jeffrey L.; Padgett, Richard W.

    2010-01-01

    Bone morphogenetic protein (BMP) pathways control an array of developmental and homeostatic events, and must themselves be exquisitely controlled. Here, we identify Caenorhabditis elegans SMA-10 as a positive extracellular regulator of BMP–like receptor signaling. SMA-10 acts genetically in a BMP–like (Sma/Mab) pathway between the ligand DBL-1 and its receptors SMA-6 and DAF-4. We cloned sma-10 and show that it has fifteen leucine-rich repeats and three immunoglobulin-like domains, hallmarks of an LRIG subfamily of transmembrane proteins. SMA-10 is required in the hypodermis, where the core Sma/Mab signaling components function. We demonstrate functional conservation of LRIGs by rescuing sma-10(lf) animals with the Drosophila ortholog lambik, showing that SMA-10 physically binds the DBL-1 receptors SMA-6 and DAF-4 and enhances signaling in vitro. This interaction is evolutionarily conserved, evidenced by LRIG1 binding to vertebrate receptors. We propose a new role for LRIG family members: the positive regulation of BMP signaling by binding both Type I and Type II receptors. PMID:20502686

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

    DTIC Science & Technology

    2011-04-01

    delivered on a collagen sponge (INFUSE Bone Graft; Medtronic) has been approved by FDA for posterior-lateral spine fusions, tibial fractures, and sinus...area was defined by drawing a quadrilateral area using the periosteal corners of the four host cortices as points of reference. The relative areas of...section of an FR +BMP scaffold in Figure 8 (the ap- proximate boundary of the implant is denoted by the box) shows a mature and fully bridged periosteal

  14. Protein intake and lumbar bone density: the Multi-Ethnic Study of Atherosclerosis (MESA).

    PubMed

    Hu, Tian; Rianon, Nahid J; Nettleton, Jennifer A; Hyder, Joseph A; He, Jiang; Steffen, Lyn M; Jacobs, David R; Criqui, Michael H; Bazzano, Lydia A

    2014-10-28

    Dietary protein has been shown to increase urinary Ca excretion in randomised controlled trials, and diets high in protein may have detrimental effects on bone health; however, studies examining the relationship between dietary protein and bone health have conflicting results. In the present study, we examined the relationship between dietary protein (total, animal and vegetable protein) and lumbar spine trabecular volumetric bone mineral density (vBMD) among participants enrolled in the Multi-Ethnic Study of Atherosclerosis (n 1658). Protein intake was assessed using a FFQ obtained at baseline examination (2000-2). Lumbar spine vBMD was measured using quantitative computed tomography (2002-5), on average 3 years later. Multivariable linear and robust regression techniques were used to examine the associations between dietary protein and vBMD. Sex and race/ethnicity jointly modified the association of dietary protein with vBMD (P for interaction = 0·03). Among white women, higher vegetable protein intake was associated with higher vBMD (P for trend = 0·03), after adjustment for age, BMI, physical activity, alcohol consumption, current smoking, educational level, hormone therapy use, menopause and additional dietary factors. There were no consistently significant associations for total and animal protein intakes among white women or other sex and racial/ethnic groups. In conclusion, data from the present large, multi-ethnic, population-based study suggest that a higher level of protein intake, when substituted for fat, is not associated with poor bone health. Differences in the relationship between protein source and race/ethnicity of study populations may in part explain the inconsistent findings reported previously.

  15. Si-doping bone composite based on protein template-mediated assembly for enhancing bone regeneration

    NASA Astrophysics Data System (ADS)

    Yang, Qin; Du, Yingying; Wang, Yifan; Wang, Zhiying; Ma, Jun; Wang, Jianglin; Zhang, Shengmin

    2017-06-01

    Bio-inspired hybrid materials that contain organic and inorganic networks interpenetration at the molecular level have been a particular focus of interest on designing novel nanoscale composites. Here we firstly synthesized a series of hybrid bone composites, silicon-hydroxyapatites/silk fibroin/collagen, based on a specific molecular assembled strategy. Results of material characterization confirmed that silicate had been successfully doped into nano-hydroxyapatite lattice. In vitro evaluation at the cellular level clearly showed that these Si-doped composites were capable of promoting the adhesion and proliferation of rat mesenchymal stem cells (rMSCs), extremely enhancing osteoblastic differentiation of rMSCs compared with silicon-free composite. More interestingly, we found there was a critical point of silicon content in the composition on regulating multiple cell behaviors. In vivo animal evaluation further demonstrated that Si-doped composites enabled to significantly improve the repair of cranial bone defect. Consequently, our current work not only suggests fabricating a potential bone repair materials by integrating element-doping and molecular assembled strategy in one system, but also paves a new way for constructing multi-functional composite materials in the future.

  16. Transcriptional regulation of gilthead seabream bone morphogenetic protein (BMP) 2 gene by bone- and cartilage-related transcription factors.

    PubMed

    Marques, Cátia L; Cancela, M Leonor; Laizé, Vincent

    2016-01-15

    Bone morphogenetic protein (BMP) 2 belongs to the transforming growth factor β (TGFβ) superfamily of cytokines and growth factors. While it plays important roles in embryo morphogenesis and organogenesis, BMP2 is also critical to bone and cartilage formation. Protein structure and function have been remarkably conserved throughout evolution and BMP2 transcription has been proposed to be tightly regulated, although few data is available. In this work we report the cloning and functional analysis of gilthead seabream BMP2 promoter. As in other vertebrates, seabream BMP2 gene has a 5′ non-coding exon, a feature already present in DPP gene, the fruit fly ortholog of vertebrate BMP2 gene, and maintained throughout evolution. In silico analysis of seabream BMP2 promoter revealed several binding sites for bone and cartilage related transcription factors (TFs) and their functionality was evaluated using promoter-luciferase constructions and TF-expressing vectors. Runt-related transcription factor 3 (RUNX3) was shown to negatively regulate BMP2 transcription and combination with the core binding factor β (CBFβ) further reduced transcriptional activity of the promoter. Although to a lesser extent, myocyte enhancer factor 2C (MEF2C) had also a negative effect on the regulation of BMP2 gene transcription, when associated with SRY (sex determining region Y)-box 9 (SOX9b). Finally, v-ets avian erythroblastosis virus E26 oncogene homolog 1 (ETS1) was able to slightly enhance BMP2 transcription. Data reported here provides new insights toward the better understanding of the transcriptional regulation of BMP2 gene in a bone and cartilage context.

  17. Use of recombinant human bone morphogenetic protein-2 with local bone graft instead of iliac crest bone graft in posterolateral lumbar spine arthrodesis.

    PubMed

    Park, Daniel K; Kim, Sung S; Thakur, Nikhil; Boden, Scott D

    2013-05-20

    Prospective clinical study. Compare fusion rates between recombinant human bone morphogenetic protein-2 (rhBMP-2) and iliac crest bone graft (ICBG) with rhBMP-2 and local bone graft (LBG) (±bone graft extenders) in posterolateral fusion. Previous reports have shown higher fusion rates when adding rhBMP-2 to ICBG in lumbar posterolateral fusion, compared with ICBG alone. We compared the fusion success rates between rhBMP-2 delivered with ICBG versus that with LBG. Fusion rates were compared in patients with degenerative spondylolisthesis (1-2 levels) with accompanying lumbar stenosis. RhBMP-2 (INFUSE, Medtronic) was delivered on an absorbable collagen sponge (6 mg/side at 1.5 mg/mL) with ICBG alone or with LBG wrapped inside the sponge. Thin slice computed tomographic scans were assessed at 6, 12, and 24 months. In a consecutive series, 16 patients (30 levels) received ICBG with rhBMP-2 and 35 patients (49 levels) received LBG with rhBMP-2. For the ICBG cohort, 80.0%, 93.4%, 96.7% of levels were fused at 6, 12, and 24 months. In contrast, for the local bone with rhBMP-2 cohort, 87.7%, 98.0%, and 98.0% were fused at 6, 12, and 24 months. There was no statistically significant difference in fusion success rates between the 2 groups at any time point. As for fusion quality, the fusion mass showed superior quality in ICBG group than in the local bone group at each time point. This study validates the high fusion success rates previously reported by adding rhBMP-2 to ICBG and shows that local bone may be safely substituted for ICBG in 1- to 2-level posterolateral fusion. The fusion rates were comparable. The avoidance of ICBG harvest has implications for operative time, blood loss, and morbidity. Lastly, this is the first study that directly compares the fusion success rate and quality using local bone with rhBMP-2 versus ICBG with rhBMP-2 at various times. 4.

  18. Temporal control of self-organized pattern formation without morphogen gradients in bacteria

    PubMed Central

    Payne, Stephen; Li, Bochong; Cao, Yangxiaolu; Schaeffer, David; Ryser, Marc D; You, Lingchong

    2013-01-01

    Diverse mechanisms have been proposed to explain biological pattern formation. Regardless of their specific molecular interactions, the majority of these mechanisms require morphogen gradients as the spatial cue, which are either predefined or generated as a part of the patterning process. However, using Escherichia coli programmed by a synthetic gene circuit, we demonstrate here the generation of robust, self-organized ring patterns of gene expression in the absence of an apparent morphogen gradient. Instead of being a spatial cue, the morphogen serves as a timing cue to trigger the formation and maintenance of the ring patterns. The timing mechanism enables the system to sense the domain size of the environment and generate patterns that scale accordingly. Our work defines a novel mechanism of pattern formation that has implications for understanding natural developmental processes. PMID:24104480

  19. Signaling mechanisms of non-conventional axon guidance cues: the Shh, BMP and Wnt morphogens.

    PubMed

    Yam, Patricia T; Charron, Frédéric

    2013-12-01

    During nervous system development, axons, led by the growth cone, must navigate to their destinations. Axon guidance cues are molecules in the extracellular environment that attract or repel axons to guide them along their correct trajectory. The non-conventional axon guidance cues include morphogens of the Hedgehog, TGF-β/BMP, and Wnt/Wgl families. Canonical signaling by morphogens regulates transcription in the nucleus to specify cell fate. Recent studies have begun to elucidate how these morphogens can also direct growth cone turning, using signaling mechanisms that diverge from their canonical signaling pathways. Furthermore, in addition to directly guiding axons, some non-conventional guidance cues such as Sonic hedgehog also modulate the response of axons to other guidance cues, adding another level of regulation to axon guidance. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. 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.

  1. Cerebral infarction associated with protein C deficiency following allogeneic bone marrow transplantation.

    PubMed

    Gordon, B G; Saving, K L; McCallister, J A; Warkentin, P I; McConnell, J R; Roberts, W M; Coccia, P F; Haire, W D

    1991-10-01

    Hypercoagulable states associated with deficiencies in circulating anticoagulant protein C occur after chemotherapy for a variety of malignant diseases. Protein C deficiency also occurs following bone marrow transplantation (BMT) and may be responsible for a variety of transplantation-associated complications. We report the case of a child who suffered a stroke associated with low protein C antigen and activity occurring 11 months after allogeneic BMT. Protein C levels recovered spontaneously by 18 months after BMT. We speculate that the protein C deficiency and and resultant hypercoagulable state led to the stroke, and the deficiency of this anticoagulant was a sequela of the transplant.

  2. Identification and characterization of cellular binding proteins (receptors) for recombinant human bone morphogenetic protein 2B, an initiator of bone differentiation cascade

    SciTech Connect

    Paralkar, V.M.; Reddi, A.H. ); Hammonds, R.G. )

    1991-04-15

    Bone morphogenetic protein 2B (BMP 2B), is a heparin-binding bone differentiation factor that initiates endochondral bone formation in rats when implanted subcutaneously. The molecular mechanism of action of this differentiation factor is not known, and as a first step the authors have examined BMP 2B-responsive cells for the presence of specific cellular binding proteins. Using {sup 125}I-labeled BMP 2B, specific high-affinity binding sites for recombinant human BMP 2B on MC3T3 E1 osteoblast-like cells as well as on NIH 3T3 fibroblasts were identified. Platelet-derived growth factor, epidermal growth factor, and transforming growth factor {beta} did not compete for the binding of radiolabeled BMP 2B. The binding of BMP 2B is a time- and temperature-dependent process. Chemical crosslinking of radiolabeled BMP showed two components. These data demonstrate specific, high-affinity cell-surface binding proteins for BMP 2B.

  3. The importance of the SIBLING family of proteins on skeletal mineralisation and bone remodelling.

    PubMed

    Staines, Katherine A; MacRae, Vicky E; Farquharson, Colin

    2012-09-01

    The small integrin-binding ligand N-linked glycoprotein (SIBLING) family consists of osteopontin, bone sialoprotein, dentin matrix protein 1, dentin sialophosphoprotein and matrix extracellular phosphoglycoprotein. These proteins share many structural characteristics and are primarily located in bone and dentin. Accumulating evidence has implicated the SIBLING proteins in matrix mineralisation. Therefore, in this review, we discuss the individual role that each of the SIBLING proteins has in this highly orchestrated process. In particular, we emphasise how the nature and extent of their proteolytic processing and post-translational modification affect their functional role. Finally, we describe the likely roles of the SIBLING proteins in clinical disorders of hypophosphataemia and their potential therapeutic use.

  4. Morphogene adsorption as a Turing instability regulator: Theoretical analysis and possible applications in multicellular embryonic systems

    PubMed Central

    Nesterenko, Alexey M.; Kuznetsov, Maxim B.; Korotkova, Daria D.; Zaraisky, Andrey G.

    2017-01-01

    The Turing instability in the reaction-diffusion system is a widely recognized mechanism of the morphogen gradient self-organization during the embryonic development. One of the essential conditions for such self-organization is sharp difference in the diffusion rates of the reacting substances (morphogens). In classical models this condition is satisfied only for significantly different values of diffusion coefficients which cannot hold for morphogens of similar molecular size. One of the most realistic explanations of the difference in diffusion rate is the difference between adsorption of morphogens to the extracellular matrix (ECM). Basing on this assumption we develop a novel mathematical model and demonstrate its effectiveness in describing several well-known examples of biological patterning. Our model consisting of three reaction-diffusion equations has the Turing-type instability and includes two elements with equal diffusivity and immobile binding sites as the third reaction substance. The model is an extension of the classical Gierer-Meinhardt two-components model and can be reduced to it under certain conditions. Incorporation of ECM in the model system allows us to validate the model for available experimental parameters. According to our model introduction of binding sites gradient, which is frequently observed in embryonic tissues, allows one to generate more types of different spatial patterns than can be obtained with two-components models. Thus, besides providing an essential condition for the Turing instability for the system of morphogen with close values of the diffusion coefficients, the morphogen adsorption on ECM may be important as a factor that increases the variability of self-organizing structures. PMID:28170437

  5. Short report: Relationship between quality protein, lean mass and bone health.

    PubMed

    Loenneke, Jeremy P; Balapur, Abhishek; Thrower, Austin D; Syler, Georganne; Timlin, Maureen; Pujol, Thomas J

    2010-01-01

    Quality protein intake, and distribution of that protein, could play an important role with lean mass (LM), bone mineral density (BMD) and bone mineral content (BMC). Research has demonstrated that muscle protein synthesis is maximally stimulated at approximately 10 g of essential amino acids (EAA)/meal. This study sought to determine the relationship between the amount of quality protein consumed and the amount of times the approximately 10 g EAA threshold was reached at a meal, with respect to LM, BMD and BMC. Twenty-seven subjects participated in this study. EAA intake was determined from a 3-day food record, and amino acid profiling was determined using a computer program (USDA Database, release 22). LM, BMD and BMC were measured using dual-energy X-ray absorptiometry. Quality protein was defined as the ratio of EAA to total dietary protein. Data were analyzed using Pearson partial coefficient correlations, controlling for body mass, with an α-level of 0.05. Quality protein consumed in a 24-hour period and the amount of times reaching the EAA threshold per day was positively associated with LM, BMD and BMC, and had an inverse relationship with body fat percentage. Both quality protein intake and frequency are positively associated with favorable body composition and bone health. Copyright © 2010 S. Karger AG, Basel.

  6. Bone Regeneration in Rat Cranium Critical-Size Defects Induced by Cementum Protein 1 (CEMP1)

    PubMed Central

    Serrano, Janeth; Romo, Enrique; Bermúdez, Mercedes; Narayanan, A. Sampath; Zeichner-David, Margarita; Santos, Leticia; Arzate, Higinio

    2013-01-01

    Gene therapy approaches to bone and periodontal tissue engineering are being widely explored. While localized delivery of osteogenic factors like BMPs is attractive for promotion of bone regeneration; method of delivery, dosage and side effects could limit this approach. A novel protein, Cementum Protein 1 (CEMP1), has recently been shown to promote regeneration of periodontal tissues. In order to address the possibility that CEMP1 can be used to regenerate other types of bone, experiments were designed to test the effect of hrCEMP1 in the repair/regeneration of a rat calvaria critical-size defect. Histological and microcomputed tomography (µCT) analyses of the calvaria defect sites treated with CEMP1 showed that after 16 weeks, hrCEMP1 is able to induce 97% regeneration of the defect. Furthermore, the density and characteristics of the new mineralized tissues were normal for bone. This study demonstrates that hrCEMP1 stimulates bone formation and regeneration and has therapeutic potential for the treatment of bone defects and regeneration of mineralized tissues. PMID:24265720

  7. [Direct bone morphogenetic protein 2 gene therapy for repairing segmental radial defect in rabbits].

    PubMed

    Li, Jianjun; Bai, Lunhao; Sun, Hongbin; Han, Dong; Gu, Jiaxiang; Wang, Huan; Duan, Jingzhu; Xu, Xinxiang

    2005-09-01

    To study the effect of direct bone morphogenetic protein 2 (BMP-2) gene therapy mediated by adenovirus on repairing bone defect. The radial defect models were made on 60 rabbits, which were evenly divided into 4 groups randomly. The 4 groups were treated with different materials: group A, adenovirus carrying BMP-2 gene (Ad-BMP-2) plus bovine cancellous bone (BCB); group B, reconstructed BMP-2 plus BCB; group C, Ad-Lacz plus BCB; and group D, only BCB scaffolds. The X-ray, histological examination, biomechanics analysis, and immunohistochemical staining were made 4, 8, and 12 weeks after the operation. Group A gained better effect in the volume of new bones, the anti-bending intensity of the healing bone, and the expression of BMP-2 than those of group B. The defect in group A was healed. No new bones were observed in group C and group D. Direct BMP-2 gene therapy is easy to perform and has very strong osteo-induction ability. It is a good method to repair segmental bone defects.

  8. Deficiency of circadian clock protein BMAL1 in mice results in a low bone mass phenotype.

    PubMed

    Samsa, William E; Vasanji, Amit; Midura, Ronald J; Kondratov, Roman V

    2016-03-01

    The circadian clock is an endogenous time keeping system that controls the physiology and behavior of many organisms. The transcription factor Brain and Muscle ARNT-like Protein 1 (BMAL1) is a component of the circadian clock and necessary for clock function. Bmal1(-/-) mice display accelerated aging and many accompanying age associated pathologies. Here, we report that mice deficient for BMAL1 have a low bone mass phenotype that is absent at birth and progressively worsens over their lifespan. Accelerated aging of these mice is associated with the formation of bony bridges occurring across the metaphysis to the epiphysis, resulting in shorter long bones. Using micro-computed tomography we show that Bmal1(-/-) mice have reductions in cortical and trabecular bone volume and other micro-structural parameters and a lower bone mineral density. Histology shows a deficiency of BMAL1 results in a reduced number of active osteoblasts and osteocytes in vivo. Isolation of bone marrow derived mesenchymal stem cells from Bmal1(-/-) mice demonstrate a reduced ability to differentiate into osteoblasts in vitro, which likely explains the observed reductions in osteoblasts and osteocytes, and may contribute to the observed osteopenia. Our data support the role of the circadian clock in the regulation of bone homeostasis and shows that BMAL1 deficiency results in a low bone mass phenotype.

  9. Deficiency of Circadian Clock Protein BMAL1 in Mice Results in a Low Bone Mass Phenotype

    PubMed Central

    Samsa, William E.; Vasanji, Amit; Midura, Ronald J.; Kondratov, Roman V.

    2016-01-01

    The circadian clock is an endogenous time keeping system that controls the physiology and behavior of many organisms. The transcription factor Brain and Muscle ARNT-like Protein 1 (BMAL1) is a component of the circadian clock and necessary for clock function. Bmal1−/− mice display accelerated aging and many accompanying age associated pathologies. Here, we report that mice deficient for BMAL1 have a low bone mass phenotype that is absent at birth and progressively worsens over their lifespan. Accelerated aging of these mice is associated with the formation of bony bridges occurring across the metaphysis to the epiphysis, resulting in shorter long bones. Using micro-computed tomography we show that Bmal1−/− mice have reductions in cortical and trabecular bone volume and other micro-structural parameters and a lower bone mineral density. Histology shows a deficiency of BMAL1 results in a reduced number of active osteoblasts and osteocytes in vivo. Isolation of bone marrow derived mesenchymal stem cells from Bmal1−/− mice demonstrate a reduced ability to differentiate into osteoblasts in vitro, which likely explains the observed reductions in osteoblasts and osteocytes, and may contribute to the observed osteopenia. Our data support the role of the circadian clock in the regulation of bone homeostasis and shows that BMAL1 deficiency results in a low bone mass phenotype. PMID:26789548

  10. Enhanced in vivo osteogenesis by nanocarrier-fused bone morphogenetic protein-4

    PubMed Central

    Shiozaki, Yasuyuki; Kitajima, Takashi; Mazaki, Tetsuro; Yoshida, Aki; Tanaka, Masato; Umezawa, Akihiro; Nakamura, Mariko; Yoshida, Yasuhiro; Ito, Yoshihiro; Ozaki, Toshifumi; Matsukawa, Akihiro

    2013-01-01

    Purpose Bone defects and nonunions are major clinical skeletal problems. Growth factors are commonly used to promote bone regeneration; however, the clinical impact is limited because the factors do not last long at a given site. The introduction of tissue engineering aimed to deter the diffusion of these factors is a promising therapeutic strategy. The purpose of the present study was to evaluate the in vivo osteogenic capability of an engineered bone morphogenetic protein-4 (BMP4) fusion protein. Methods BMP4 was fused with a nanosized carrier, collagen-binding domain (CBD), derived from fibronectin. The stability of the CBD-BMP4 fusion protein was examined in vitro and in vivo. Osteogenic effects of CBD-BMP4 were evaluated by computer tomography after intramedullary injection without a collagen–sponge scaffold. Recombinant BMP-4, CBD, or vehicle were used as controls. Expressions of bone-related genes and growth factors were compared among the groups. Osteogenesis induced by CBD-BMP4, BMP4, and CBD was also assessed in a bone-defect model. Results In vitro, CBD-BMP4 was retained in a collagen gel for at least 7 days while BMP4 alone was released within 3 hours. In vivo, CBD-BMP4 remained at the given site for at least 2 weeks, both with or without a collagen–sponge scaffold, while BMP4 disappeared from the site within 3 days after injection. CBD-BMP4 induced better bone formation than BMP4 did alone, CBD alone, and vehicle after the intramedullary injection into the mouse femur. Bone-related genes and growth factors were expressed at higher levels in CBD-BMP4-treated mice than in all other groups, including BMP4-treated mice. Finally, CBD-BMP4 potentiated more bone formation than did controls, including BMP4 alone, when applied to cranial bone defects without a collagen scaffold. Conclusion Altogether, nanocarrier-CBD enhanced the retention of BMP4 in the bone, thereby promoting augmented osteogenic responses in the absence of a scaffold. These results

  11. Evaluation of bovine-derived bone protein with a natural coral carrier as a bone-graft substitute in a canine segmental defect model.

    PubMed

    Sciadini, M F; Dawson, J M; Johnson, K D

    1997-11-01

    The efficacy of a bone-graft substitute (bovine-derived bone protein in a carrier of natural coral) in the healing of a segmental defect of a weight-bearing long bone was evaluated. Twenty dogs, divided into two groups, underwent bilateral radial osteotomies with creation of a 2.5 cm defect. On one side of each dog, the defect was filled with autogenous cancellous bone graft. Contralateral defects received, in a blinded randomized fashion, cylindrical implants consisting of natural coral (calcium carbonate) or calcium carbonate enhanced with a standard dose of bovine-derived bone protein (3.0 mg/implant; 0.68 mg bone protein/cm3). The limbs were stabilized with external fixators, and all animals underwent monthly radiographs. They were killed at 12 (group 1) or 24 (group 2) weeks, and regenerated bone was studied by biomechanical testing and histology. Radiographic union developed in all 20 radii with autogenous cancellous bone grafts and in all 10 of the radii with the composite implants. None of the radii with implants of calcium carbonate alone showed radiographic evidence of union. This represented a statistically significant difference between implant types. In addition, calcium carbonate implants both with and without bone protein demonstrated radiographic evidence of near total resorption of the radiodense carrier by 12 weeks. This resorption facilitated radiographic evaluation of healing. Mean values for biomechanical parameters of radii with the composite implants exceeded those for the contralateral controls at 12 and 24 weeks; the difference was statistically significant at 12 weeks. Histology revealed scant residual calcium carbonate carrier at either time in the defects with calcium carbonate implants; however, a moderate amount was present in defects with the composite implants. In these specimens, the residual carrier was completely surrounded by newly formed bone that may have insulated the calcium carbonate from further degradation. The present

  12. Role of morphogenetic proteins in skeletal tissue engineering and regeneration.

    PubMed

    Reddi, A H

    1998-03-01

    Morphogenesis is the developmental cascade of pattern formation and body plan establishment, culminating in the adult form. It has formed the basis for the emerging discipline of tissue engineering, which uses principles of molecular developmental biology and morphogenesis gleaned through studies on inductive signals, responding stem cells, and the extracellular matrix to design and construct spare parts that restore function to the human body. Among the many organs in the body, bone has considerable powers for regeneration and is a prototype model for tissue engineering. Implantation of demineralized bone matrix into subcutaneous sites results in local bone induction. This model mimics sequential limb morphogenesis and has permitted the isolation of bone morphogens, such as bone morphogenetic proteins (BMPs), from demineralized adult bone matrix. BMPs initiate, promote, and maintain chondrogenesis and osteogenesis, but are also involved in the morphogenesis of organs other than bone. The symbiosis of the mechanisms underlying bone induction and differentiation is critical for tissue engineering and is governed by both biomechanics (physical forces) and context (microenvironment/extracellular matrix), which can be duplicated by biomimetic biomaterials such as collagens, hydroxyapatite, proteoglycans, and cell adhesion glycoproteins, including fibronectins and laminin. Rules of tissue architecture elucidated in bone morphogenesis may provide insights into tissue engineering and be universally applicable for all organs/tissues, including bones and joints.

  13. Secreted frizzled-related protein 1 modulates glucocorticoid attenuation of osteogenic activities and bone mass.

    PubMed

    Wang, Feng-Sheng; Lin, Chun-Liang; Chen, Yeung-Jen; Wang, Ching-Jen; Yang, Kuender D; Huang, Yu-Ting; Sun, Yi-Chih; Huang, Hui-Chen

    2005-05-01

    Prolonged glucocorticoid treatment is known to cause osteoporosis or aseptic necrosis. Secreted frizzled-related proteins 1 (SFRP1) and low-density lipoprotein-related protein 5 (LRP5), a Wnt protein antagonist and a coreceptor, have been found to regulate skeletogenesis. Whereas recent studies have reported that excess glucocorticoid promotes bone loss, the biological role of SFRP1 and LRP5 in regulating glucocorticoid attenuation of bone formation is not fully understood. We showed that a supraphysiological level of glucocorticoid enhanced SFRP1 but not LRP5 expression of primary mesenchymal cell cultures in vitro and osteoblasts at metaphyseal trabecular endosteum and chondrocytes at calcified cartilage in vivo. Glucocorticoid augmentation of SFRP1 expression was transcriptionally mediated. The inhibitory action of glucocorticoid on osteogenic differentiation appeared to be regulated by SFRP1 mediation of beta-catenin destabilization because knocking down SFRP1 by RNA interference abrogated the supraphysiological level of glucocorticoid attenuation of osteogenesis. Recombinant human SFRP1 reduced the promoting effect of physiological level of glucocorticoid on cytosolic beta-catenin accumulation, runt-related transcription factor-2 activation, and osteogenic activities. Glucocorticoid and recombinant human SFRP1 significantly increased osteochondral cell apoptosis associated with reduced mineral density, biomechanical properties, trabecular bone volume, and midshaft cortical bone areas in rat femurs. These findings suggest that SFRP1 modulates glucocorticoid-induced bone loss. Regulation of Wnt/SFRP signal transduction can be used in the future as an alternative strategy for the prevention of glucocorticoid-induced osteoporosis.

  14. Slow rates of degradation of osteocalcin: Green light for fossil bone protein?

    NASA Astrophysics Data System (ADS)

    Collins, M. J.; Gernaey, A. M.; Nielsen-Marsh, C. M.; Vermeer, C.; Westbroek, P.

    2000-12-01

    Our claim, published in this journal, for successful immunodetection of the protein osteocalcin in dinosaur bone has been challenged on the grounds that the findings are inconsistent with the kinetics of decomposition. Here we show that the close association of osteocalcin to the bone mineral vastly enhances its preservation potential relative to the same protein in aqueous solution. We conducted heating experiments (75 95 °C) of modern bone powder and monitored the survival of three different regions of osteocalcin (N-terminal, His4-Hyp9; C-terminal, Phe45-Val49; and the mid-region, Pro15-Glu31) with monoclonal antibodies. Extrapolation of our data to 10 °C ambient burial temperatures indicates that preservation of the γ-carboxylated mid-region in fossil bone cannot be excluded on kinetic grounds. Clearly, in situ sequence analysis will be the only method by which the preservation of fossil macromolecules will be unequivocally established. Nevertheless, our findings demonstrate the importance of mineral association to protein survival, as was borne out by an investigation of Holocene (ca. 6 ka) bones. Only in those samples with little recrystallization was the γ-carboxylated mid-region well preserved. These results imply that the future success of ancient biomolecule research largely depends on our understanding the interaction between these materials and their environment throughout diagenesis.

  15. Modeling and Validation of Multilayer Poly(Lactide-Co-Glycolide) Scaffolds for In Vitro Directed Differentiation of Juxtaposed Cartilage and Bone.

    PubMed

    Huang, George X; Arany, Praveen R; Mooney, David J

    2015-08-01

    Polymeric scaffolds, which release growth factors in a temporally controlled manner, have successfully directed the differentiation of stem cells into monolithic tissues of a single lineage. However, engineering precise boundaries in multilineage functional tissues, such as the juxtaposed cartilaginous and osseous tissue present in articulated joints, often remains a challenge. This work demonstrates a precise materials system for in vitro reconstruction of the three-dimensional architecture of these types of human tissues. Multilayer poly(lactide-co-glycolide) (PLG) scaffolds were used to produce spatiotemporal gradients to direct the differentiation of an initially uniform population of mesenchymal stem cells (MSCs) into juxtaposed cartilage and bone. Specifically, growth factors (chondrogenic transforming growth factor-β3 and osteogenic bone morphogenetic protein-4) and their neutralizing antibodies were incorporated within distinct layers of the PLG scaffolds to create spatially segregated morphogen fields within the scaffold volume. The multilayer PLG scaffold designs were optimized by mathematical modeling, and generation of spatially segregated morphogen gradients was validated by assessing activity of luciferase reporter cell lines responsive to each growth factor. Scaffolds seeded with MSCs demonstrated production of juxtaposed cartilage and bone, as evaluated by biochemical staining and western blotting for tissue-specific matrix proteins. This work demonstrates a significant advance for the engineering of implantable constructs comprising tissues of multiple lineages, with potential applications in orthopedic regenerative medicine.

  16. Bone lineage proteins in the entheses of the midfoot in patients with spondyloarthritis.

    PubMed

    Pacheco-Tena, César; Pérez-Tamayo, Ruy; Pineda, Carlos; González-Chávez, Susana A; Quiñonez-Flores, Celia; Ugalde Vitelly, Antonio; Inman, Robert D; Aubin, Jane E; Vázquez-Mellado, Janitzia; Burgos-Vargas, Rubén

    2015-04-01

    Patients with juvenile-onset spondyloarthritis (SpA) may develop ankylosis of the midfoot resembling the spinal changes seen in patients with ankylosing spondylitis (AS). The study of the histopathology of the feet of patients with tarsitis could help us understand the pathogenesis of bone formation in affected structures in the SpA. The objective of our study was to describe the histopathologic characteristics of the midfoot in patients with tarsitis associated with SpA. We obtained synovial sheaths, entheses, and bone samples from 20 patients with SpA with midfoot pain/tenderness and swelling. Tissue samples underwent H&E staining; immunohistochemistry for CD3, CD4, CD8, CD68, and CD20 cell identification; and immunofluorescence for bone lineage proteins, including osteocalcin, osteopontin, parathyroid hormone-related protein, bone sialoprotein, and alkaline phosphatase. Slight edema and hyalinization were found in some tendon sheaths, and few inflammatory cells were detected in the entheses. In bones, we found some changes suggesting osteoproliferation, including endochondral and intramembranous ossification, but no inflammatory cells. In entheses showing bone proliferation, we detected osteocalcin and osteopontin in cells with a fibroblast-mesenchymal phenotype, suggesting the induction of entheseal cells toward an osteoblast phenotype. Osteoproliferation and abnormal expression of bone lineage proteins, but no inflammatory infiltration, characterize midfoot involvement in patients with SpA. In this sense, tarsitis (or ankylosing tarsitis) resembles the involvement of the spine in patients with AS. Ossification may be in part explained by the differentiation of mesenchymal entheseal cells toward the osteoblastic lineage.

  17. Effects of ionizing radiation on proteins in lyophilized or frozen demineralized human bone

    PubMed Central

    Antebi, Uri; Mathor, Monica Beatriz; da Silva, André Ferreira; Guimarães, Rodrigo Pereira; Honda, Emerson Kiyoshi

    2016-01-01

    Objective The aim was to study the effects of application of ionizing radiation (gamma and electrons) as sterilizing agents at doses of 15 kGy, 25 kGy and 50 kGy, on lyophilized or frozen demineralized bone tissue for use in transplants. Methods Five human femoral diaphyses from different donors of musculoskeletal tissue were demineralized and preserved as lyophilized or frozen at −80 °C. The samples were divided into two groups: non-irradiated (control) and irradiated by means of gamma rays or an electron beam. The bone proteins were extracted and used to determine the concentrations of total protein and BMP 2 and 7. Results Decreases in total protein and BMP 2 and 7 concentrations were observed. The decreases in total protein concentrations, in comparison with the respective control groups, were significant in the lyophilized and frozen samples that were irradiated at a dose of 50 kGy of gamma radiation and electron beam, with reductions of more than 30%. Significant decreases in the levels of BMP 2 and 7 were also observed at higher doses and especially through use of the electron beam. Conclusion The reductions in the concentrations of total proteins and osteoinductive proteins (BMP 2 and 7) were related to the radiation dose, i.e. they increased with higher doses of ionizing radiation type and the type of bone preservation. The largest reductions in concentrations were observed in the bones irradiated by means of an electron beam and at a dose of 50 kGy. However, this type of radiation and this high dose are not usual practices for sterilization of bone tissue. PMID:27069893

  18. Measurement of serum C reactive protein concentration after bone marrow transplantation for leukaemia.

    PubMed Central

    Rowe, I F; Worsley, A M; Donnelly, P; Catovsky, D; Goldman, J M; Galton, D; Pepys, M B

    1984-01-01

    C reactive protein concentration was measured serially in 19 patients with leukaemia after bone marrow transplantation. Six episodes of graft versus host disease occurred in the presence of fever but with no evidence of infection, and these were associated with C reactive protein concentrations as high as 200 mg/l. C reactive protein values were also increased in 12 febrile episodes associated with infection, in seven of which graft versus host disease was also present. C reactive protein concentrations are of no value in differentiating infection from graft versus host disease, but in both cases they may be useful as an objective index of response to appropriate treatment. PMID:6365979

  19. TGF-β and BMP signaling in osteoblast, skeletal development, and bone formation, homeostasis and disease

    PubMed Central

    Wu, Mengrui; Chen, Guiqian; Li, Yi-Ping

    2016-01-01

    Transforming growth factor-beta (TGF-β) and bone morphogenic protein (BMP) signaling has fundamental roles in both embryonic skeletal development and postnatal bone homeostasis. TGF-βs and BMPs, acting on a tetrameric receptor complex, transduce signals to both the canonical Smad-dependent signaling pathway (that is, TGF-β/BMP ligands, receptors, and Smads) and the non-canonical-Smad-independent signaling pathway (that is, p38 mitogen-activated protein kinase/p38 MAPK) to regulate mesenchymal stem cell differentiation during skeletal development, bone formation and bone homeostasis. Both the Smad and p38 MAPK signaling pathways converge at transcription factors, for example, Runx2 to promote osteoblast differentiation and chondrocyte differentiation from mesenchymal precursor cells. TGF-β and BMP signaling is controlled by multiple factors, including the ubiquitin–proteasome system, epigenetic factors, and microRNA. Dysregulated TGF-β and BMP signaling result in a number of bone disorders in humans. Knockout or mutation of TGF-β and BMP signaling-related genes in mice leads to bone abnormalities of varying severity, which enable a better understanding of TGF-β/BMP signaling in bone and the signaling networks underlying osteoblast differentiation and bone formation. There is also crosstalk between TGF-β/BMP signaling and several critical cytokines’ signaling pathways (for example, Wnt, Hedgehog, Notch, PTHrP, and FGF) to coordinate osteogenesis, skeletal development, and bone homeostasis. This review summarizes the recent advances in our understanding of TGF-β/BMP signaling in osteoblast differentiation, chondrocyte differentiation, skeletal development, cartilage formation, bone formation, bone homeostasis, and related human bone diseases caused by the disruption of TGF-β/BMP signaling. PMID:27563484

  20. BMP2-coprecipitated calcium phosphate granules enhance osteoinductivity of deproteinized bovine bone, and bone formation during critical-sized bone defect healing

    PubMed Central

    Liu, Tie; Zheng, Yuanna; Wu, Gang; Wismeijer, Daniel; Pathak, Janak L.; Liu, Yuelian

    2017-01-01

    Most materials used clinically for filling critical-sized bone defects (CSBD), such as deproteinized bovine bone (DBB), lack osteoinductivity so that their therapeutic effects are far from satisfactory. The effect of bone morphogenic protein 2 (BMP2)-coprecipitated biomimetic calcium phosphate granules (BMP2-cop.BioCaP) on osteoinduction of DBB graft(s) during CSBD healing is still unknown. We investigated whether BMP2-cop.BioCaP affects the osteoinductivity of DBB, bone formation, and foreign body reaction during CSBD healing. DBB + BMP2-cop.BioCaP, DBB, DBB + BMP2, DBB + BioCaP, and autologous bone grafts were implanted in the CSBD of sheep. Bone formation, DBB/BioCaP degradability, foreign body reaction, and osteoinductivity of DBB were analyzed histologically and histomorphometrically at week 4 and 8. Combination of BMP2-cop.BioCaP and DBB healed CSBD as effectively as autologous bone grafts. About 95% of the BMP2-cop.BioCaP had been degraded and replaced by new bone at week 8 in the DBB + BMP2-cop.BioCaP-group. Foreign body reaction was reduced in the DBB + BMP2-cop.BioCaP-group compared to the other groups. The independent use of the BMP2-cop.BioCaP did not achieve a satisfactory bone repair. In conclusion, the BMP2-cop.BioCaP showed good degradability and biocompatibility, and enhanced osteoinductivity of DBB during CSBD healing in sheep, suggesting BMP2-cop.BioCaP as a potential osteoinducer to enhance the therapeutic effects of the graft materials in clinic. PMID:28139726

  1. Application of bone morphogenetic proteins in the treatment of clinical oral and maxillofacial osseous defects.

    PubMed

    Boyne, P J

    2001-01-01

    Commonly occurring extensive osseous defects in the oral and maxillofacial area are seen following complete or partial resection of the mandible and other facial bones in oncologic surgery or following traumatic injury. Autogenous osseous grafts have been used to restore these defects. Additionally, bone graft substitute materials and autogenous osseous grafts are applied to congenital defects such as cleft palate, facial clefts, and facial asymmetry. We have simulated these types of defects in appropriately aged Macaca fascicularis and Macaca mulatta monkeys to study the efficacy of using bone morphogenetic protein (BMP) as an osseous inductor. The objective of these studies was to obtain information on the feasibility of employing bone inductors to regenerate large continuity critical-sized maxillofacial defects without using bone grafts. In one study, involving eight animals, the body of the mandible was removed, simulating hemi-mandibulectomy defects following traumatic bone loss or oncologic surgery. Recombinant human (rh) BMP-2 (Genetics Institute, Cambridge, Massachusetts) in a collagen carrier (Colla-Tec Inc., Plainsboro, New Jersey) then was placed in the hemi-mandibulectomy defect with use of titanium orthopaedic mesh fixation (Sofamor Danek-Medtronic, Memphis, Tennessee). Entire bone regeneration of the defect was observed 5 and 6 months postoperatively. In another group of subhuman primates, the restored area was functionally stimulated at the 5-month post-BMP implantation level by placement of intraoral titanium implants. The animals were allowed to function for 8 months with these titanium implants. Microscopic results showed increased density, bone volume, and thickness of the trabecular bone pattern. The bone cortex in the restored defect also increased in thickness compared with the nonsurgical areas. To evaluate the effect of rhBMP-2 in aging individuals, a group of six Macaca animals over 20 years of age received the same type of mandibular

  2. Secreted Protein Acidic and Rich in Cysteine (SPARC) Mediates Metastatic Dormancy of Prostate Cancer in Bone *

    PubMed Central

    Sharma, Sambad; Xing, Fei; Liu, Yin; Wu, Kerui; Said, Neveen; Pochampally, Radhika; Shiozawa, Yusuke; Lin, Hui-Kuan; Balaji, K. C.; Watabe, Kounosuke

    2016-01-01

    Prostate cancer is known to frequently recur in bone; however, how dormant cells switch its phenotype leading to recurrent tumor remains poorly understood. We have isolated two syngeneic cell lines (indolent and aggressive) through in vivo selection by implanting PC3mm stem-like cells into tibial bones. We found that indolent cells retained the dormant phenotype, whereas aggressive cells grew rapidly in bone in vivo, and the growth rates of both cells in culture were similar, suggesting a role of the tumor microenvironment in the regulation of dormancy and recurrence. Indolent cells were found to secrete a high level of secreted protein acidic and rich in cysteine (SPARC), which significantly stimulated the expression of BMP7 in bone marrow stromal cells. The secreted BMP7 then kept cancer cells in a dormant state by inducing senescence, reducing “stemness,” and activating dormancy-associated p38 MAPK signaling and p21 expression in cancer cells. Importantly, we found that SPARC was epigenetically silenced in aggressive cells by promoter methylation, but 5-azacytidine treatment reactivated the expression. Furthermore, high SPARC promoter methylation negatively correlated with disease-free survival of prostate cancer patients. We also found that the COX2 inhibitor NS398 down-regulated DNMTs and increased expression of SPARC, which led to tumor growth suppression in bone in vivo. These findings suggest that SPARC plays a key role in maintaining the dormancy of prostate cancer cells in the bone microenvironment. PMID:27422817

  3. Sustained mitogen-activated protein kinase activation with Aggregatibacter actinomycetemcomitans causes inflammatory bone loss.

    PubMed

    Dunmyer, J; Herbert, B; Li, Q; Zinna, R; Martin, K; Yu, H; Kirkwood, K L

    2012-10-01

    Aggregatibacter actinomycetemcomitans is a gram-negative facultative capnophile involved in pathogenesis of aggressive forms of periodontal disease. In the present study, we interrogated the ability of A. actinomycetemcomitans to stimulate innate immune signaling and cytokine production and established that A. actinomycetemcomitans causes bone loss in a novel rat calvarial model. In vitro studies indicated that A. actinomycetemcomitans stimulated considerable production of soluble cytokines, tumor necrosis factor-α, interleukin-6 and interleukin-10 in both primary bone marrow-derived macrophages and NR8383 macrophages. Immunoblot analysis indicated that A. actinomycetemcomitans exhibits sustained activation of all major mitogen-activated protein kinase (MAPK) pathways, as well as the negative regulator of MAPK signaling, MAPK phosphatase-1 (MKP-1), for at least 8 h. In a rat calvarial model of inflammatory bone loss, high and low doses of formalin-fixed A. actinomycetemcomitans were microinjected into the supraperiosteal calvarial space for 1-2 weeks. Histological staining and micro-computed tomography of rat calvariae revealed a significant increase of inflammatory and fibroblast infiltrate and increased bone resorption as measured by total lacunar pit formation. From these data, we provide new evidence that fixed whole cell A. actinomycetemcomitans stimulation elicits a pro-inflammatory host response through sustained MAPK signaling, leading to enhanced bone resorption within the rat calvarial bone.

  4. Combined inhibition of morphogen pathways demonstrates additive antifibrotic effects and improved tolerability.

    PubMed

    Distler, Alfiya; Lang, Veronika; Del Vecchio, Tina; Huang, Jingang; Zhang, Yun; Beyer, Christian; Lin, Neng-Yu; Palumbo-Zerr, Katrin; Distler, Oliver; Schett, Georg; Distler, Jörg Hw

    2014-06-01

    The morphogen pathways Hedgehog, Wnt and Notch are attractive targets for antifibrotic therapies in systemic sclerosis. Interference with stem cell regeneration, however, may complicate the use of morphogen pathway inhibitors. We therefore tested the hypothesis that combination therapies with low doses of Hedgehog, Wnt and Notch inhibitors maybe safe and effective for the treatment of fibrosis. Skin fibrosis was induced by bleomycin and by overexpression of a constitutively active TGF-β receptor type I. Adverse events were assessed by clinical monitoring, pathological evaluation and quantification of Lgr5-positive intestinal stem cells. Inhibition of Hedgehog, Wnt and Notch signalling dose-dependently ameliorated bleomycin-induced and active TGF-β receptor type I-induced fibrosis. Combination therapies with low doses of Hedgehog/Wnt inhibitors or Hedgehog/Notch inhibitors demonstrated additive antifibrotic effects in preventive as well as in therapeutic regimes. Combination therapies were well tolerated. In contrast with high dose monotherapies, combination therapies did not reduce the number of Lgr5 positive intestinal stem cells. Combined inhibition of morphogen pathways exerts additive antifibrotic effects. Combination therapies are well tolerated and, in contrast to high dose monotherapies, may not impair stem cell renewal. Combined targeting of morphogen pathways may thus help to overcome dose-limiting toxicity of Hedgehog, Wnt and Notch signalling.

  5. Efficiently engineered cell sheet using a complex of polyethylenimine–alginate nanocomposites plus bone morphogenetic protein 2 gene to promote new bone formation

    PubMed Central

    Jin, Han; Zhang, Kai; Qiao, Chunyan; Yuan, Anliang; Li, Daowei; Zhao, Liang; Shi, Ce; Xu, Xiaowei; Ni, Shilei; Zheng, Changyu; Liu, Xiaohua; Yang, Bai; Sun, Hongchen

    2014-01-01

    Regeneration of large bone defects is a common clinical problem. Recently, stem cell sheet has been an emerging strategy in bone tissue engineering. To enhance the osteogenic potential of stem cell sheet, we fabricated bone morphogenetic protein 2 (BMP-2) gene-engineered cell sheet using a complex of polyethylenimine–alginate (PEI–al) nanocomposites plus human BMP-2 complementary(c)DNA plasmid, and studied its osteogenesis in vitro and in vivo. PEI–al nanocomposites carrying BMP-2 gene could efficiently transfect bone marrow mesenchymal stem cells. The cell sheet was made by culturing the cells in medium containing vitamin C for 10 days. Assays on the cell culture showed that the genetically engineered cells released the BMP-2 for at least 14 days. The expression of osteogenesis-related gene was increased, which demonstrated that released BMP-2 could effectively induce the cell sheet osteogenic differentiation in vitro. To further test the osteogenic potential of the cell sheet in vivo, enhanced green fluorescent protein or BMP-2-producing cell sheets were treated on the cranial bone defects. The results indicated that the BMP-2-producing cell sheet group was more efficient than other groups in promoting bone formation in the defect area. Our results suggested that PEI–al nanocomposites efficiently deliver the BMP-2 gene to bone marrow mesenchymal stem cells and that BMP-2 gene-engineered cell sheet is an effective way for promoting bone regeneration. PMID:24855355

  6. Effect of Recombinant Human Bone Morphogenetic Protein-2 and Adipose Tissue-Derived Stem Cell on New Bone Formation in High-Speed Distraction Osteogenesis.

    PubMed

    Lee, Sung Joo; Kim, Byung Jun; Kim, Young Il; Sohn, Chul-Ho; Jeon, Yoon Kyung; Xu, Lianji; Kim, Sang Hyon; Kwon, Sun Young; Choi, Tae Hyun; Kim, Suk Wha

    2016-01-01

    The effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) and osteogenically differentiated adipose tissue-derived stem cells (ADSC) on new bone formation in high-speed distraction osteogenesis of adult rabbit cranium were investigated. A total of 41 adult rabbits were used in the study. Distraction began after a 5-day latency period at a rate of 1.5 mm twice a day until 10-mm length gain was obtained both in the control group, where a bone defect was induced, and in the experimental group, in which ADSC (group A), rhBMP-2 (group B), or both (group C) were injected in the distraction gap after distraction. At 4, 8, and 12 weeks after distraction, computed tomography analysis was done to determine the bone defect dimension and bone mineral density (BMD), while histologic examination was also done to calculate bone formation ratio. Bone defect dimension significantly decreased in groups B and C, compared with the control group, at 4 and 12 weeks after distraction. BMD was significantly increased in groups B and C at 4 weeks. On histologic examination, bone formation ratio was significantly increased in group C only at 12 weeks. This study suggests that the use of rhBMP-2 in combination with or without ADSC is helpful to promote bone regeneration in high-speed distraction osteogenesi s of adult rabbit cranium.

  7. 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.

  8. 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

  9. [Frontiers in Live Bone Imaging Researches. Novel fluorescent proteins for in vivo imaging].

    PubMed

    Tomura, Michio

    2015-06-01

    Bone tissue is maintained by dynamic equilibrium of various types of cells. Thus, real time intravital imaging of movement and phenotypic changes of cells in the steady state and in pathophysiological state help us to understand molecular mechanism of bone tissue maintenance. Therefore, this review introduces Fucci-Tg mice for cell cycle imaging, caspase-3 indicator SCAT3.1 mice for cell death, and photoconvertible protein Kaede-Tg mice and cell-type specific KikGR mice for visualization of cell movement within intra-organ and between inter-organs.

  10. 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.

  11. Biomineralization of Engineered Spider Silk Protein-Based Composite Materials for Bone Tissue Engineering.

    PubMed

    Hardy, John G; Torres-Rendon, Jose Guillermo; Leal-Egaña, Aldo; Walther, Andreas; Schlaad, Helmut; Cölfen, Helmut; Scheibel, Thomas R

    2016-07-11

    Materials based on biodegradable polyesters, such as poly(butylene terephthalate) (PBT) or poly(butylene terephthalate-co-poly(alkylene glycol) terephthalate) (PBTAT), have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein, the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16)), that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate is reported. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering.

  12. Inorganic polymers: morphogenic inorganic biopolymers for rapid prototyping chain.

    PubMed

    Müller, Werner E G; Schröder, Heinz C; Shen, Zhijian; Feng, Qingling; Wang, Xiaohong

    2013-01-01

    In recent years, considerable progress has been achieved towards the development of customized scaffold materials, in particular for bone tissue engineering and repair, by the introduction of rapid prototyping or solid freeform fabrication techniques. These new fabrication techniques allow to overcome many problems associated with conventional bone implants, such as inadequate external morphology and internal architecture, porosity and interconnectivity, and low reproducibility. However, the applicability of these new techniques is still hampered by the fact that high processing temperature or a postsintering is often required to increase the mechanical stability of the generated scaffold, as well as a post-processing, i.e., surface modification/functionalization to enhance the biocompatibility of the scaffold or to bind some bioactive component. A solution might be provided by the introduction of novel inorganic biopolymers, biosilica and polyphosphate, which resist harsh conditions applied in the RP chain and are morphogenetically active and do not need supplementation by growth factors/cytokines to stimulate the growth and the differentiation of bone-forming cells.

  13. Serum levels of bone Gla-protein in inhabitants exposed to environmental cadmium

    SciTech Connect

    Kido, T.; Honda, R.; Tsuritani, I.; Ishizaki, M.; Yamada, Y.; Nakagawa, H.; Nogawa, K.; Dohi, Y. )

    1991-01-01

    Serum levels of bone Gla-protein (BGP)--the vitamin K-dependent CA2(+)-binding protein--were evaluated in 76 cadmium (Cd)-exposed subjects with renal tubular dysfunction (32 men, 44 women) and 133 nonexposed subjects (53 men, 80 women). Serum BGP levels were higher in the Cd-exposed subjects than in nonexposed subjects. Significant correlations between BGP and each index measured by bone microdensitometry (MD), serum alkaline phosphatase activity, and Cd in blood and urine were found. For all of the Cd-exposed and nonexposed men and women, BGP showed a significant standard partial regression coefficient (multiple regression analysis) with the metacarpal index (MCI), which was one of the MD indicators. Bone Gla-protein also correlated significantly with urinary beta 2-microglobulin in the men and with serum creatinine in the women. Serum BGP values strongly reflect the degree of bone damage and also reflect, although less strongly, the degree of renal damage induced by exposure to Cd.

  14. Cell and protein compatible 3D bioprinting of mechanically strong constructs for bone repair.

    PubMed

    Sawkins, M J; Mistry, P; Brown, B N; Shakesheff, K M; Bonassar, L J; Yang, J

    2015-07-02

    Rapid prototyping of bone tissue engineering constructs often utilizes elevated temperatures, organic solvents and/or UV light for materials processing. These harsh conditions may prevent the incorporation of cells and therapeutic proteins in the fabrication processes. Here we developed a method for using bioprinting to produce constructs from a thermoresponsive microparticulate material based on poly(lactic-co-glycolic acid) at ambient conditions. These constructs could be engineered with yield stresses of up to 1.22 MPa and Young's moduli of up to 57.3 MPa which are within the range of properties of human cancellous bone. Further study showed that protein-releasing microspheres could be incorporated into the bioprinted constructs. The release of the model protein lysozyme from bioprinted constructs was sustainted for a period of 15 days and a high degree of protein activity could be measured up to day 9. This work suggests that bioprinting is a viable route to the production of mechanically strong constructs for bone repair under mild conditions which allow the inclusion of viable cells and active proteins.

  15. TGF-β and BMP Signaling in Osteoblast Differentiation and Bone Formation

    PubMed Central

    Chen, Guiqian; Deng, Chuxia; Li, Yi-Ping

    2012-01-01

    Transforming growth factor-beta (TGF-β)/bone morphogenic protein (BMP) signaling is involved in a vast majority of cellular processes and is fundamentally important throughout life. TGF-β/BMPs have widely recognized roles in bone formation during mammalian development and exhibit versatile regulatory functions in the body. Signaling transduction by TGF-β/BMPs is specifically through both canonical Smad-dependent pathways (TGF-β/BMP ligands, receptors and Smads) and non-canonical Smad-independent signaling pathway (e.g. p38 mitogen-activated protein kinase pathway, MAPK). Following TGF-β/BMP induction, both the Smad and p38 MAPK pathways converge at the Runx2 gene to control mesenchymal precursor cell differentiation. The coordinated activity of Runx2 and TGF-β/BMP-activated Smads is critical for formation of the skeleton. Recent advances in molecular and genetic studies using gene targeting in mice enable a better understanding of TGF-β/BMP signaling in bone and in the signaling networks underlying osteoblast differentiation and bone formation. This review summarizes the recent advances in our understanding of TGF-β/BMP signaling in bone from studies of genetic mouse models and human diseases caused by the disruption of TGF-β/BMP signaling. This review also highlights the different modes of cross-talk between TGF-β/BMP signaling and the signaling pathways of MAPK, Wnt, Hedgehog, Notch, and FGF in osteoblast differentiation and bone formation. PMID:22298955

  16. Bone Marrow Mesenchymal Stem Cells Expressing Baculovirus-Engineered Bone Morphogenetic Protein-7 Enhance Rabbit Posterolateral Fusion.

    PubMed

    Liao, Jen-Chung

    2016-07-05

    Previous studies have suggested that bone marrow-derived mesenchymal stem cells (BMDMSCs) genetically modified with baculoviral bone morphogenetic protein-2 (Bac-BMP-2) vectors could achieve successful fusion in a femur defect model or in a spinal fusion model. In this study, BMDMSCs expressing BMP-7 (Bac-BMP-7-BMDMSCs) were generated. We hypothesized that Bac-BMP-7-BMDMSCs could secrete more BMP-7 than untransduced BMDMSCs in vitro and achieve spinal posterolateral fusion in a rabbit model. Eighteen rabbits underwent posterolateral fusion at L4-5. Group I (n = 6) was implanted with collagen-β-tricalcium phosphate (TCP)-hydroxyapatite (HA), Group II (n = 6) was implanted with collagen-β-TCP-HA plus BMDMSCs, and Group III (n = 6) was implanted with collagen-β-TCP-HA plus Bac-BMP-7-BMDMSCs. In vitro production of BMP-7 was quantified with an enzyme-linked immunosorbent assay (ELISA). Spinal fusion was examined using computed tomography (CT), manual palpation, and histological analysis. ELISA demonstrated that Bac-BMP-7-BMDMSCs produced four-fold to five-fold more BMP-7 than did BMDMSCs. In the CT results, 6 fused segments were observed in Group I (50%, 6/12), 8 in Group II (67%, 8/12), and 12 in Group III (100%, 12/12). The fusion rate, determined by manual palpation, was 0% (0/6) in Group I, 0% (0/6) in Group II, and 83% (5/6) in Group III. Histology showed that Group III had more new bone and matured marrow formation. In conclusion, BMDMSCs genetically transduced with the Bac-BMP-7 vector could express more BMP-7 than untransduced BMDMSCs. These Bac-BMP-7-BMDMSCs on collagen-β-TCP-HA scaffolds were able to induce successful spinal fusion in rabbits.

  17. Biomineralization of bone: a fresh view of the roles of non-collagenous proteins

    PubMed Central

    Gorski, Jeffrey Paul

    2015-01-01

    The impact of genetics has dramatically affected our understanding of the functions of non-collagenous proteins. Specifically, mutations and knockouts have defined their cellular spectrum of actions. However, the biochemical mechanisms mediated by non-collagenous proteins in biomineralization remain elusive. It is likely that this understanding will require more focused functional testing at the protein, cell, and tissue level. Although initially viewed as rather redundant and static acidic calcium binding proteins, it is now clear that non-collagenous proteins in mineralizing tissues represent diverse entities capable of forming multiple protein-protein nteractions which act in positive and negative ways to regulate the process of bone mineralization. Several new examples from the author’s laboratory are provided which illustrate this theme including an apparent activating effect of hydroxyapatite crystals on metalloproteinases. This review emphasizes the view that secreted non-collagenous proteins in mineralizing bone actively participate in the mineralization process and ultimately control where and how much mineral crystal is deposited, as well as determining the quality and biomechanical properties of the mineralized matrix produced. PMID:21622198

  18. Biomineralization of bone: a fresh view of the roles of non-collagenous proteins.

    PubMed

    Gorski, Jeffrey Paul

    2011-06-01

    The impact of genetics has dramatically affected our understanding of the functions of non-collagenous proteins. Specifically, mutations and knockouts have defined their cellular spectrum of actions. However, the biochemical mechanisms mediated by non-collagenous proteins in biomineralization remain elusive. It is likely that this understanding will require more focused functional testing at the protein, cell, and tissue level. Although initially viewed as rather redundant and static acidic calcium binding proteins, it is now clear that non-collagenous proteins in mineralizing tissues represent diverse entities capable of forming multiple protein-protein interactions which act in positive and negative ways to regulate the process of bone mineralization. Several new examples from the author's laboratory are provided which illustrate this theme including an apparent activating effect of hydroxyapatite crystals on metalloproteinases. This review emphasizes the view that secreted non-collagenous proteins in mineralizing bone actively participate in the mineralization process and ultimately control where and how much mineral crystal is deposited, as well as determining the quality and biomechanical properties of the mineralized matrix produced.

  19. The Effect of a Whey Protein Supplement on Bone Mass in Older Caucasian Adults.

    PubMed

    Kerstetter, Jane E; Bihuniak, Jessica D; Brindisi, Jennifer; Sullivan, Rebecca R; Mangano, Kelsey M; Larocque, Sarah; Kotler, Belinda M; Simpson, Christine A; Cusano, Anna Maria; Gaffney-Stomberg, Erin; Kleppinger, Alison; Reynolds, Jesse; Dziura, James; Kenny, Anne M; Insogna, Karl L

    2015-06-01

    It has been assumed that the increase in urine calcium (Ca) that accompanies an increase in dietary protein was due to increased bone resorption. However, studies using stable Ca isotopes have found that dietary protein increases Ca absorption without increasing bone resorption. The objective of the study was to investigate the impact of a moderately high protein diet on bone mineral density (BMD). This was a randomized, double-blind, placebo-controlled trial of protein supplementation daily for 18 months. The study was conducted at two institutional research centers. Two hundred eight older women and men with a body mass index between 19 and 32 kg/m(2) and a self-reported protein intake between 0.6 and 1.0 g/kg participated in the study. Subjects were asked to incorporate either a 45-g whey protein or isocaloric maltodextrin supplement into their usual diet for 18 months. BMD by dual-energy x-ray absorptiometry, body composition, and markers of skeletal and mineral metabolism were measured at baseline and at 9 and 18 months. There were no significant differences between groups for changes in L-spine BMD (primary outcome) or the other skeletal sites of interest. Truncal lean mass was significantly higher in the protein group at 18 months (P = .048). C-terminal telopeptide (P = .0414), IGF-1 (P = .0054), and urinary urea (P < .001) were also higher in the protein group at the end of the study period. There was no difference in estimated glomerular filtration rate at 18 months. Our data suggest that protein supplementation above the recommended dietary allowance (0.8 g/kg) may preserve fat-free mass without adversely affecting skeletal health or renal function in healthy older adults.

  20. The Effect of a Whey Protein Supplement on Bone Mass in Older Caucasian Adults

    PubMed Central

    Kerstetter, Jane E.; Brindisi, Jennifer; Sullivan, Rebecca R.; Mangano, Kelsey M.; Larocque, Sarah; Kotler, Belinda M.; Simpson, Christine A.; Cusano, Anna Maria; Gaffney-Stomberg, Erin; Kleppinger, Alison; Reynolds, Jesse; Dziura, James; Kenny, Anne M.; Insogna, Karl L.

    2015-01-01

    Context: It has been assumed that the increase in urine calcium (Ca) that accompanies an increase in dietary protein was due to increased bone resorption. However, studies using stable Ca isotopes have found that dietary protein increases Ca absorption without increasing bone resorption. Objective: The objective of the study was to investigate the impact of a moderately high protein diet on bone mineral density (BMD). Design: This was a randomized, double-blind, placebo-controlled trial of protein supplementation daily for 18 months. Setting: The study was conducted at two institutional research centers. Participants: Two hundred eight older women and men with a body mass index between 19 and 32 kg/m2 and a self-reported protein intake between 0.6 and 1.0 g/kg participated in the study. Intervention: Subjects were asked to incorporate either a 45-g whey protein or isocaloric maltodextrin supplement into their usual diet for 18 months. Main Outcome Measure: BMD by dual-energy x-ray absorptiometry, body composition, and markers of skeletal and mineral metabolism were measured at baseline and at 9 and 18 months. Results: There were no significant differences between groups for changes in L-spine BMD (primary outcome) or the other skeletal sites of interest. Truncal lean mass was significantly higher in the protein group at 18 months (P = .048). C-terminal telopeptide (P = .0414), IGF-1 (P = .0054), and urinary urea (P < .001) were also higher in the protein group at the end of the study period. There was no difference in estimated glomerular filtration rate at 18 months. Conclusion: Our data suggest that protein supplementation above the recommended dietary allowance (0.8 g/kg) may preserve fat-free mass without adversely affecting skeletal health or renal function in healthy older adults. PMID:25844619

  1. 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.

  2. Inverse immunostaining pattern for synthesized versus endocytosed alpha-granule proteins in human bone marrow megakaryocytes.

    PubMed

    de Larouzière, V; Brouland, J P; Souni, F; Drouet, L; Cramer, E

    1998-06-01

    The time of appearance and pattern of expression of several alpha-granule proteins, von Willebrand factor (VWF), fibrinogen and immunoglobulins (Ig) were examined and compared in human bone marrow megakaryocytes (MK) using an immunocytochemical approach. VWF is synthesized by immature MK, whereas it has been shown that fibrinogen is incorporated from the plasma into alpha-granules. The present study was undertaken in order to determine whether there are chronological and morphological differences in the expression of VWF and fibrinogen in vivo in human MK. Seven paraffin-embedded biopsies of normal human bone marrow were labelled with specific antibodies for VWF and for fibrinogen, detected by the alkaline phosphatase anti-alkaline phosphatase (APAAP) method. and analysed by immunomorphometry. We found a clear, statistically significant. difference in the labelling pattern of VWF and fibrinogen. The expression of other endocytosed alpha-granule proteins, immunoglobulins G and A, was therefore studied in bone marrow MK from two patients with multiple myeloma, one with monoclonal IgG and one with monoclonal IgA. The immunostaining pattern was similar to that of fibrinogen and different from VWF, and characteristic of endocytosed alpha-granule proteins. This study demonstrates that: (i) immunohistochemical staining of MK alpha-granules proteins distinguishes the peripheral cockade distribution pattern of endocytosed protein from the perinuclear pattern of endogenously synthesized proteins; (ii) VWF is present in human bone marrow MK when fibrinogen is not yet detectable: (iii) VWF synthesis ceases while fibrinogen is still being incorporated: (iv) immunoglobulins can be detected in MK cytoplasm, with a staining pattern resembling that of fibrinogen.

  3. Diversity of bone matrix adhesion proteins modulates osteoblast attachment and organization of actin cytoskeleton.

    PubMed

    Demais, V; Audrain, C; Mabilleau, G; Chappard, D; Baslé, M F

    2014-06-01

    Interaction of cells with extracellular matrix is an essential event for differentiation, proliferation and activity of osteoblasts. In bone, binding of osteoblasts to bone matrix is required to determine specific activities of the cells and to synthesize matrix bone proteins. Integrins are the major cell receptors involved in the cell linkage to matrix proteins such as fibronectin, type I collagen and vitronectin, via the RGD-sequences. In this study, cultures of osteoblast-like cells (Saos-2) were done on coated glass coverslips in various culture conditions: DMEM alone or DMEM supplemented with poly-L-lysine (PL), fetal calf serum (FCS), fibronectin (FN), vitronectin (VN) and type I collagen (Col-I). The aim of the study was to determine the specific effect of these bone matrix proteins on cell adherence and morphology and on the cytoskeleton status. Morphological characteristics of cultured cells were studied using scanning electron microscopy and image analysis. The heterogeneity of cytoskeleton was studied using fractal analysis (skyscrapers and blanket algorithms) after specific preparation of cells to expose the cytoskeleton. FAK and MAPK signaling pathways were studied by western blotting in these various culture conditions. Results demonstrated that cell adhesion was reduced with PL and VN after 240 min. After 60 min of adhesion, cytoskeleton organization was enhanced with FN, VN and Col-I. No difference in FAK phosphorylation was observed but MAPK phosphorylation was modulated by specific adhesion on extracellular proteins. These results indicate that culture conditions modulate cell adhesion, cytoskeleton organization and intracellular protein pathways according to extracellular proteins present for adhesion.

  4. A novel protein C inhibitor gene mutation in pediatric stroke patients after bone marrow transplantation.

    PubMed

    Torun, Didem; Deda, Gülhis; Ertem, Mehmet; Uysal, Zümrüt; Yılmaz, Erkan; Akar, Nejat

    2013-09-01

    Protein C inhibitor is a heparin dependent serine protease inhibitor found in human plasma, urine and other body fluids. It was originally identified as an inhibitor of activated protein C. Stroke is an important cause of morbidity and mortality in the pediatric age group. In this study we analyzed the protein C inhibitor gene mutations in Turkish pediatric stroke patients. We found a missense mutation of G to A at nucleotide 6760 in exon 2, resulting in a transition serine to asparagine (p.Ser188Asp) and in a child and his father and also we found same alteration in exon 2 in an another pediatric stroke case following bone marrow transplantation.

  5. 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

  6. Morphogenesis and tissue engineering of bone and cartilage: inductive signals, stem cells, and biomimetic biomaterials.

    PubMed

    Reddi, A H

    2000-08-01

    Morphogenesis is the developmental cascade of pattern formation, body plan establishment, and the architecture of mirror-image bilateral symmetry of many structures and asymmetry of some, culminating in the adult form. Tissue engineering is the emerging discipline of design and construction of spare parts for the human body to restore function based on principles of molecular developmental biology and morphogenesis governed by bioengineering. The three key ingredients for both morphogenesis and tissue engineering are inductive signals, responding stem cells, and the extracellular matrix. Among the many tissues in the human body, bone has considerable powers for regeneration and is a prototype model for tissue engineering based on morphogenesis. Implantation of demineralized bone matrix into subcutaneous sites results in local bone induction. This model mimics sequential limb morphogenesis and permitted the isolation of bone morphogens. Although it is traditional to study morphogenetic signals in embryos, bone morphogenetic proteins (BMPs), the inductive signals for bone, were isolated from demineralized bone matrix from adults. BMPs and related cartilage-derived morphogenetic proteins (CDMPs) initiate, promote, and maintain chondrogenesis and osteogenesis and have actions beyond bone. The symbiosis of bone inductive and conductive strategies are critical for tissue engineering, and is in turn governed by the context and biomechanics. The context is the microenvironment, consisting of extracellular matrix, which can be duplicated by biomimetic biomaterials such as collagens, hydroxyapatite, proteoglycans, and cell adhesion proteins including fibronectins. Thus, the rules of architecture for tissue engineering are an imitation of the laws of developmental biology and morphogenesis, and thus may be universal for all tissues, including bones and joints.

  7. Dietary protein level and source differentially affect bone metabolism, strength, and intestinal calcium transporter expression during ad libitum and food-restricted conditions in male rats

    USDA-ARS?s Scientific Manuscript database

    High protein diets may attenuate bone loss during energy restriction (ER). The objective of the current study was to determine whether high protein diets suppress bone turnover and improve bone quality in rats during ER and whether dietary protein source affects this relationship. Eighty 12-week o...

  8. A BolA-like morphogene from the alga Chlamydomonas reinhardtii changes morphology and induces biofilm formation in Escherichia coli.

    PubMed

    Khona, Dolly K; Dongre, Shounak S; Arraiano, Cecilia M; D'Souza, Jacinta S

    2013-02-01

    Escherichia coli BolA protein is a stress-inducible morphogene, regulates transcription, forms biofilms and interacts with monothiol glutaredoxins. Its presence has been documented in plants but its role remains enigmatic. This study attempts to functionally dissect the role of a BolA-domain-containing protein in the alga Chlamydomonas reinhardtii. Of the five C. reinhardtii bolA-like genes annotated for the presence of BolA-domain, the open reading frame with the highest similarity to algal systems was cloned and the protein over-expressed in E. coli. This over-expression did not affect E. coli growth but induced biofilm formation and changed its morphology, indicating functional conservancy. This is the first compelling evidence depicting the role of a plant BolA-like protein in morphogenetic pathway and biofilm formation. The implications of the phenotypic consequences of this heterologous expression are discussed. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  9. Protein kinase D1 is essential for bone acquisition during pubertal growth.

    PubMed

    Ford, Jeffery J; Yeh, Lee-Chuan C; Schmidgal, Eric C; Thompson, Jason F; Adamo, Martin L; Lee, John C

    2013-11-01

    Bone formation and maintenance represents the summation of the balance of local and endocrine hormonal stimuli within a complex organ. Protein kinase D (PKD) is a member of the Ca(2+)/calmodulin-dependent kinase superfamily of serine/threonine kinases and has been described as the crossroads for the bone morphogenetic protein (BMP)-IGF-I signaling axis, which plays a major role in bone formation. The current study exploits the PKD1-deficient mouse model to examine the role of PKD in vivo in the skeleton. Dual-energy x-ray absorptiometry scan analysis of male and female pubescent mice demonstrated significantly decreased bone mineral density in the whole body and femoral bone compartments of PKD1 (+/-) mice, compared with their wild-type littermates. The body weight, nasal-anal length, and percentage body fat of the mice were not significantly different from their wild-type littermates. Cultured bone marrow stromal cells from PKD1 (+/-) mice demonstrated lower alkaline phosphatase activity in early differentiating osteoblasts and decreased mineralized nodule formation in mature osteoblasts. Quantitative RT-PCR analysis of osteoblast differentiation markers and osteoclast markers exhibited lower levels of expression in PKD1 (+/-) male mice than wild type. In female mice, however, only markers of osteoblast differentiation were reduced. PKD1 (+/-) mice also demonstrated a profound reduction in mRNA expression levels of BMP type II receptor and IGF-I receptor and in BMP-7 responsiveness in vitro. Together these data suggest that in mice, PKD1 action contributes to the regulation of osteoblastogenesis by altering gene expression with gender-specific effects on osteoclastogenesis, subsequently affecting skeletal matrix acquisition during puberty.

  10. Bone morphogenetic proteins, cementogenesis, myoblastic stem cells and the induction of periodontal tissue regeneration.

    PubMed

    Ripamonti, Ugo; Petit, Jean-Claude

    2009-01-01

    'Bone: Formation by autoinduction', initiates by invocation of soluble molecular signals which, when combined to insoluble signals or substrata trigger the ripple-like cascade of bone differentiation by induction. The osteogenic proteins of the transforming growth factor-beta (TGF-beta) superfamily, the bone morphogenetic/osteogenic proteins (BMPs/OPs), and uniquely in the non-human primate Papio ursinus also the three mammalian TGF-beta isoforms, induce endochondral bone formation as recapitulation of embryonic development. The pleiotropic activities of the BMPs/OPs are vast and include the induction of periodontal tissue regeneration. Implantation of naturally derived highly purified osteogenic fractions after sequential adsorption/affinity and gel filtration chromatography in mandibular Class II furcation defects of P. ursinus induces cementogenesis as highly cellular collagenic cementoid attached to the exposed dentine with foci of nascent mineralization with inserted de novo generated Sharpey's fibres. Recombinant human osteogenic protein-1 (hOP-1) when implanted in Class II furcation defects of P. ursinus with surgically exposed dentine matrix preferentially initiates the induction of cementogenesis; on the other hand, hBMP-2 preferentially induces alveolar bone regeneration with mineralized bone covered by prominent osteoid seams. Long-term studies with gamma-irradiated 0.5 and 2.5mg hOP-1 per gram of xenogeneic bovine collagenous matrix induce the restitutio ad integrum of the periodontal tissues in furcation defects exposed by chronic periodontitis in P. ursinus. A challenging question for tissue engineering and regenerative medicine is whether the presence of molecularly different osteogenic proteins of the TGF-beta superfamily has a therapeutic significance. Mechanistically, the specificity of hOP-1 primarily initiating cementogenesis in periodontal defects is regulated by both the dentine extracellular matrix upon which responding cells attach and

  11. 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.

  12. Activation of Protein Kinase A in Mature Osteoblasts Promotes a Major Bone Anabolic Response.

    PubMed

    Tascau, Liana; Gardner, Thomas; Anan, Hussein; Yongpravat, Charlie; Cardozo, Christopher P; Bauman, William A; Lee, Francis Y; Oh, Daniel S; Tawfeek, Hesham A

    2016-01-01

    Protein kinase A (PKA) regulates osteoblast cell function in vitro and is activated by important bone mass modulating agents. We determined whether PKA activation in osteoblasts is sufficient to mediate a bone anabolic response. Thus, a mouse model conditionally expressing a constitutively active PKA (CA-PKA) in osteoblasts (CA-PKA-OB mouse) was developed by crossing a 2.3-kb α1 (I)-collagen promoter-Cre mouse with a floxed-CA-PKA mouse. Primary osteoblasts from the CA-PKA-OB mice exhibited higher basal PKA activity than those from control mice. Microcomputed tomographic analysis revealed that CA-PKA-OB female mice had an 8.6-fold increase in femoral but only 1.16-fold increase in lumbar 5 vertebral bone volume/total volume. Femur cortical thickness and volume were also higher in the CA-PKA-OB mice. In contrast, alterations in many femoral microcomputed tomographic parameters in male CA-PKA-OB mice were modest. Interestingly, the 3-dimensional structure model index was substantially lower both in femur and lumbar 5 of male and female CA-PKA-OB mice, reflecting an increase in the plate to rod-like structure ratio. In agreement, femurs from female CA-PKA-OB mice had greater load to failure and were stiffer compared with those of control mice. Furthermore, the CA-PKA-OB mice had higher levels of serum bone turnover markers and increased osteoblast and osteoclast numbers per total tissue area compared with control animals. In summary, constitutive activation of PKA in osteoblasts is sufficient to increase bone mass and favorably modify bone architecture and improve mechanical properties. PKA activation in mature osteoblasts is, therefore, an important target for designing anabolic drugs for treating diseases with bone loss.

  13. Parathyroid hormone-related protein is a gravisensor in lung and bone cell biology

    NASA Astrophysics Data System (ADS)

    Torday, J. S.

    2003-10-01

    Parathyroid Hormone-related Protein (PTHrP) has been shown to be essential for the development and homeostatic regulation of lung and bone. Since both lung and bone structure and function are affected by microgravity, we hypothesized that 0 × g down-regulates PTHrP signaling. To test this hypothesis, we suspended lung and bone cells in the simulated microgravity environment of a Rotating Wall Vessel Bioreactor, which simulates microgravity, for up to 72 hours. During the first 8 hours of exposure to simulated 0 × g, PTHrP expression fell precipitously, decreasing by 80-90%; during the subsequent 64 hours, PTHrP expression remained at this newly established level of expression. PTHrP production decreased from 12 pg/ml/hour to 1 pg/ml/hour in culture medium from microgravity-exposed cells. The cells were then recultured at unit gravity for 24hours, and PTHrP expression and production returned to normal levels. Based on these findings, we have obtained bones from rats flown in space for 2 weeks (Mission STS-58, SL-2). Analysis of PTHrP expression by femurs and tibias from these animals (n=5) revealed that PTHrP expression was 60% lower than in bones from control ground-based rats. Interestingly, there were no differences in PTHrP expression by parietal bone from space-exposed versus ground-based animals, indicating that the effect of weightlessness on PTHrP expression is due to the unweighting of weight-bearing bones. This finding is consistent with other studies of microgravity-induced osteoporosis. The loss of the PTHrP signaling mechanism may be corrected using chemical agents that up-regulate this pathway. In conclusion, PTHrP represents a stretch-sensitive paracrine signaling mechanism that may sense gravity.

  14. Parathyroid hormone-related protein (pthrp) is a gravisensor for lung and bone.

    NASA Astrophysics Data System (ADS)

    Torday, J.

    Parathyroid Hormone-related Protein (PTHrP) and its receptor represent a stretch- sensitive paracrine signaling mechanism (Torday, 1999) that may sense gravity. PTHrP has been shown to be essential for the development and homeostatic regulation of lung (Rubin et al, 2000) and bone (Kronenberg et al, 1994). Since both lung and bone structure and function are affected by microgravity, we hypothesized that microgravity down-regulates PTHrP signaling. To test this hypothesis, we suspended lung and bone cells in the microgravity environment of a rotating wall vessel apparatus, which simulates microgravity, for up to 72 hours. During the first 6-8 hours, PTHrP expression fell precipitously, decreasing by 80-90%; during the subsequent 64-66 hours, PTHrP expression remained at this newly established level. PTHrP production decreased from 5 pmol/ml/3hours to undetectable levels in culture medium from microgravity-exposed cells. The cells were then put back in culture at unit gravity for 24hours, and PTHrP expression and production returned to normal levels. Based on these findings, we have obtained bones from rats flown in space for 2 weeks (mission SLS-2, provided courtesy of the Biospecimen Facility, Ames Research Center, NASA, as a result of a peer-reviewed proposal). Analysis of PTHrP expression by femurs and tibias from these animals (n=5) revealed that PTHrP expression was 60% lower than in bones from ground-based rats. Interestingly, there were no differences in PTHrP exp ression by parietal bones, indicating that the effect of weightlessness on PTHrP expression is due to the unweighting of weight-bearing bones. This finding is consistent with other studies of microgravity-induced osteoporosis. The loss of the PTHrP signaling mechanism may be corrected using chemical agents that up-regulate this pathway.

  15. 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

  16. Peripheral skeleton bone strength is positively correlated with total and dairy protein intakes in healthy postmenopausal women.

    PubMed

    Durosier-Izart, Claire; Biver, Emmanuel; Merminod, Fanny; van Rietbergen, Bert; Chevalley, Thierry; Herrmann, François R; Ferrari, Serge L; Rizzoli, René

    2017-02-01

    Bone mineral content (BMC) and bone mineral density (BMD) are positively correlated with dietary protein intakes, which account for 1-8% of BMC and BMD variances. However, the relation between bone strength and microstructure, which are variables that are not captured by areal bone mineral density (aBMD), and dietary protein intakes, particularly from specific dietary sources, has not been clearly established. We investigated the association between the peripheral skeleton-predicted failure load and stiffness, bone microstructure, and dietary protein intakes from various origins (animal, divided into dairy and nondairy, and vegetable origins) in healthy postmenopausal women. In a cross-sectional study in 746 Caucasian women aged 65.0 ± 1.4 y, we measured the aBMD with the use of dual-energy X-ray absorptiometry, the distal radius and tibia bone microstructures with the use of high-resolution peripheral quantitative computerized tomography, and bone strength with the use of a finite element analysis, and we evaluated dietary protein and calcium with the use of a validated food-frequency questionnaire. Mean dietary calcium and protein intakes were greater than recommended amounts for this class of age. The predicted failure load and stiffness at the distal radius and tibia were positively associated with total, animal, and dairy protein intakes but not with vegetable protein intake. Failure load differences were accompanied by modifications of the aBMD and of cortical and trabecular bone microstructures. The associations remained statistically significant after adjustment for weight, height, physical activity, menopause duration, calcium intake, and the interaction between calcium and protein intake. A principal component analysis of the volumetric BMD and bone microstructure indicated that trabecular bone mainly contributed to the positive association between protein intakes and bone strength. These results, which were recorded in a very homogeneous population of

  17. Extractable bone morphogenetic protein and correlation with induced new bone formation in an in vivo assay in the athymic mouse model.

    PubMed

    Honsawek, Sittisak; Powers, Ralph M; Wolfinbarger, Lloyd

    2005-01-01

    A correlation between extractable bone morphogenetic proteins (BMPs) in demineralized bone matrix (DBM) and osteoinduction has been suggested. Extractable BMP-4 and osteoinductivity of DBM from 40 donors were assessed using enzyme-linked immunosorbent assay (ELISA) and in vivo athymic mouse assay, respectively. Extractable BMP-4 level averaged 3.7 +/- 0.21 ng/g of DBM and correlated with osteoinductivity of the DBM in an in vivo assessment of induced newbone formation.

  18. [Degradation of biomolecules: a comparative study of diagenesis of DNA and proteins in human bone tissue].

    PubMed

    Harbeck, Michaela; Ritz-Timme, Stefanie; Schröder, Inge; Oehmichen, Manfred; von Wurmb-Schwark, Nicole

    2004-12-01

    Diagenesis of macromolecules is a not yet fully understood process that can be important for anthropological and forensic research. Trying to elucidate the diagenesis of DNA and proteins we investigated the process of fragmentation of DNA and razemisation of aspartic acid in human bone material. We created an in vitro-model of accelerated aging by incubating bone samples in hot water. A comparison of diagenesis of molecules in those artificially aged samples with altogether 30 historical bones from different regions and of different ages was carried out. The in vitro-model showed the expected positive correlation between the increase of razemisation of aspartic acid and DNA fragmentation, while there was a much lesser correlation when investigating historical bones. The in vitro-model showed the expected correlation between the increase of razemisation of aspartic acid and DNA fragmentation and to a much lesser extent in historical bones. This study shows that diagenesis is probably influenced by additional forces affecting different macromolecules in different ways.

  19. A Review of the Clinical Side Effects of Bone Morphogenetic Protein-2

    PubMed Central

    James, Aaron W.; LaChaud, Gregory; Shen, Jia; Asatrian, Greg; Nguyen, Vi; Zhang, Xinli

    2016-01-01

    Bone morphogenetic protein-2 (BMP-2) is currently the only Food and Drug Administration (FDA)-approved osteoinductive growth factor used as a bone graft substitute. However, with increasing clinical use of BMP-2, a growing and well-documented side effect profile has emerged. This includes postoperative inflammation and associated adverse effects, ectopic bone formation, osteoclast-mediated bone resorption, and inappropriate adipogenesis. Several large-scale studies have confirmed the relative frequency of adverse events associated with the clinical use of BMP-2, including life-threatening cervical spine swelling. In fact, the FDA has issued a warning of the potential life-threatening complications of BMP-2. This review summarizes the known adverse effects of BMP-2, including controversial areas such as tumorigenesis. Next, select animal models that replicate BMP-2's adverse clinical effects are discussed. Finally, potential molecules to mitigate the adverse effects of BMP-2 are reviewed. In summary, BMP-2 is a potent osteoinductive cytokine that has indeed revolutionized the bone graft substitute market; however, it simultaneously has accrued a worrisome side effect profile. Better understanding of these adverse effects among both translational scientists and clinicians will help determine the most appropriate and safe use of BMP-2 in the clinical setting. PMID:26857241

  20. Reduced trabecular bone mass and strength in mice overexpressing Gα11 protein in cells of the osteoblast lineage.

    PubMed

    Dela Cruz, Ariana; Mattocks, Michael; Sugamori, Kim S; Grynpas, Marc D; Mitchell, Jane

    2014-02-01

    G protein-coupled receptors (GPCRs) require G proteins for intracellular signaling to regulate a variety of growth and maintenance processes, including osteogenesis and bone turnover. Bone maintenance events may be altered by changes in the activity or level of G proteins, which then modify signaling in bone cells such as osteoblasts. We have previously reported increased levels of Gα11 protein and signaling to phospholipase C/protein kinase C pathways in response to dexamethasone in osteoblastic UMR 106-01 cells. Here we generated pOBCol3.6-GNA11 transgenic mice that overexpress Gα11 protein in cells of the osteoblast lineage (G11-Tg mice). G11-Tg mice exhibit an osteopenic phenotype characterized by significant reductions in trabecular bone mineral density, thickness, number and strength. The numbers of osteoblasts and osteocytes were unchanged in G11-Tg bone, but early markers of osteoblast differentiation, Alp and Bsp, were increased while the late stage differentiation marker Ocn was not changed suggesting reduced osteoblast maturation in G11-Tg trabecular bone which was accompanied by a decreased bone formation rate. Furthermore, in vitro cultures of G11-Tg primary osteoblasts show delayed osteoblast differentiation and mineralization. Histological analyses also revealed increased osteoclast parameters, accompanied by elevated mRNA expression of Trap and Ctsk. mRNA levels of Rankl and M-csf were elevated in vitro in bone marrow stromal cells undergoing osteogenesis and in trabecular bone in vivo. Together, these findings demonstrate that increasing Gα11 protein expression in osteoblasts can alter gene expression and result in a dual mechanism of trabecular bone loss.

  1. Mesenchyme-specific overexpression of nucleolar protein 66 in mice inhibits skeletal growth and bone formation

    PubMed Central

    Chen, Qin; Zhang, Liping; de Crombrugghe, Benoit; Krahe, Ralf

    2015-01-01

    Previous studies showed that nucleolar protein 66 (NO66), the Jumonji C-domain-containing histone demethylase for methylated histone H3K4 and H3K36 (H3K36me), negatively regulates osteoblast differentiation in vitro by inhibiting the activity of transcription factor osterix (Osx). However, whether NO66 affects mammalian skeletogenesis in vivo is not yet known. Here, we generated transgenic (TG) mice overexpressing a flag-tagged NO66 transgene driven by the Prx1 (paired related homeobox 1) promoter. We found that NO66 overexpression in Prx1-expressing mesenchymal cells inhibited skeletal growth and bone formation. The inhibitory phenotype was associated with >50% decreases in chondrocyte/osteoblast proliferation and differentiation. Moreover, we found that in bones of NO66-TG mice, expression of Igf1, Igf1 receptor (Igf1r), runt-related transcription factor 2, and Osx was significantly down-regulated (P < 0.05). Consistent with these results, we observed >50% reduction in levels of phosphorylated protein kinase B (Akt) and H3K36me3 in bones of NO66-TG mice, suggesting an inverse correlation between NO66 histone demethylase and the activity of IGF1R/Akt signaling. This correlation was further confirmed by in vitro assays of C2C12 cells with NO66 overexpression. We propose that the decrease in the IGF1R/Akt signaling pathway in mice with mesenchymal overexpression of NO66 may contribute in part to the inhibition of skeletal growth and bone formation.—Chen, Q., Zhang, L., de Crombrugghe, B., Krahe, R. Mesenchyme-specific overexpression of nucleolar protein 66 in mice inhibits skeletal growth and bone formation. PMID:25746793

  2. [Prevention of osteoporosis by foods and dietary supplements. Milk basic protein (MBP) induces alveolar bone formation in rat experimental periodontitis].

    PubMed

    Seto, Hiroyuki; Nagata, Toshihiko

    2006-10-01

    Periodontitis is a chronic inflammatory disease caused by infection of periodontopathic bacteriae, which induced alveolar bone resorpotion. Milk basic protein (MBP) has been reported to be useful as a supplement because of increasing bone formation in animal and human studies. We examined the effect of MBP for alveolar bone formation in rat experimental periodontitis. After alveolar bone resorption was induced by ligature technique, the diets containing low and high dose of MBP were given to rats for 90 days. Micro-focus computed tomography and histological observation revealed a recovery of alveolar bone in high-dose MBP group compared to the control group. Osteoid thickness of alveolar bone crest significantly increased in low and high-dose MBP groups. These findings indicate that MBP may be effective for the recovery of alveolar bone resorption in periodontitis.

  3. 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.

  4. Osteointegration of hydroxyapatite-titanium implants coated with nonglycosylated recombinant human bone morphogenetic protein-2 (BMP-2) in aged sheep.

    PubMed

    Sachse, A; Wagner, A; Keller, M; Wagner, O; Wetzel, W-D; Layher, F; Venbrocks, R-A; Hortschansky, P; Pietraszczyk, M; Wiederanders, B; Hempel, H J; Bossert, J; Horn, J; Schmuck, K; Mollenhauer, J

    2005-11-01

    Osteointegration of metal implants into aged organisms can be severely compromised due to reduced healing capacity of bone, lack of precursor cells for new bone formation, or osteoporosis. Here, we report on successful implant healing in a novel model of aged sheep in the presence of nonglycosylated bone morphogenetic protein 2 (BMP-2). Ewes of 8 to 12 years with significant radiologic and histologic signs of osteoporosis and adipocytic bone marrow received a cylindrical hydroxyapatite-titanium implant of 12 x 10 mm. BMP-2 has been produced as a bacterial recombinant fusion protein with maltose-binding protein and in vitro generation of mature BMP-2 by renaturation and proteolytic cleavage. A BMP-2 inhibition ELISA was developed to measure the in vitro release kinetics of bioactive human BMP-2 from immersed solid implant materials by using Escherichia coli expressed and biotinylated recombinant human BMP-2 receptor IA extracellular domain (ALK-3 ECD). The implants were placed laterally below both tibial plateaus, with the left leg implant carrying 380 microg BMP-2. Both implant types became integrated within the following 20 weeks. The control implant only integrated at the cortical bone, and little new bone formation was found within the pre-existing trabecular bone or the marrow cavity. Marrow fat tissue was partially replaced by unspecific connective tissue. In contrast, BMP-2-coated implants initiated significant new bone formation, initially in trabecular arrangements to be replaced by cortical-like bone after 20 weeks. The new bone was oriented towards the cylinder. Highly viable bone marrow appeared and filled the lacunar structures of the new bone. In mechanical tests, the BMP-2-coated implants displayed in average 50% higher stability. This animal model provided first evidence that application of nonglycosylated BMP-2 coated on solid implants may foster bone healing and regeneration even in aged-compromised individuals.

  5. Comparative effect of soy protein, soy isoflavones, and 17beta-estradiol on bone metabolism in adult ovariectomized rats.

    PubMed

    Cai, David J; Zhao, Yongdong; Glasier, Jennifer; Cullen, Diane; Barnes, Stephen; Turner, Charles H; Wastney, Meryl; Weaver, Connie M

    2005-05-01

    This study provided a comprehensive investigation on the effect of soy protein and soy isoflavones on both calcium and bone metabolism in virgin adult rats. The measurements included bone histology, calcium kinetic modeling, calcium balance, bone densitometry, and whole body densitometry. Results confirmed the bone-preserving effect of estrogen but did not support a bone-sparing role of soy isoflavones. Several animal and short-term human studies have indicated that soy protein isolate enriched with isoflavones may be used as an alternative therapy to estrogen replacement therapy. However, none of the previous studies have investigated this estrogenic effect on both calcium and bone metabolism in animals or humans, which is essential in ascertaining the mode of action of isoflavones. This study was designed to determine the effects of soy protein versus isoflavones on calcium and bone metabolism in an ovariectomized rat model. Unmated 6-month-old ovariectomized and sham-operated female Sprague-Dawley rats were randomly assigned to nine groups (16 rats/group) and pair-fed soy- or casein-based diets with or without isoflavones for 8 weeks. A reference group was administered estrogen through subcutaneous implants (20-35 pg/liter plasma). Bone densitometry, histomorphometry, and mechanical testing were used to study bone metabolism and quality. Calcium metabolism was studied using calcium tracer balance and kinetics. After ovariectomy, estrogen prevented bone loss in trabecular bone and suppressed formation on both trabecular and cortical bone surfaces. Isoflavones given as enriched soy protein isolate or supplements did not prevent trabecular bone loss. Combining isoflavones with estrogen had no additional benefits over estrogen alone. There were no differences in response to isoflavones caused by protein source. None of the treatments significantly affected either total Ca balance or (45)Ca absorption. However, soy protein showed significant effects on reducing

  6. Protein Expression Profiling of Giant Cell Tumors of Bone Treated with Denosumab.

    PubMed

    Mukaihara, Kenta; Suehara, Yoshiyuki; Kohsaka, Shinji; Akaike, Keisuke; Tanabe, Yu; Kubota, Daisuke; Ishii, Midori; Fujimura, Tsutomu; Kazuno, Saiko; Okubo, Taketo; Takagi, Tatsuya; Yao, Takashi; Kaneko, Kazuo; Saito, Tsuyoshi

    2016-01-01

    Giant cell tumors of bone (GCTB) are locally aggressive osteolytic bone tumors. Recently, some clinical trials have shown that denosumab is a novel and effective therapeutic option for aggressive and recurrent GCTB. This study was performed to investigate the molecular mechanism underlying the therapeutic effect of denosumab. Comparative proteomic analyses were performed using GCTB samples which were taken before and after denosumab treatment. Each expression profile was analyzed using the software program to further understand the affected biological network. One of identified proteins was further evaluated by gelatin zymography and an immunohistochemical analysis. We identified 13 consistently upregulated proteins and 19 consistently downregulated proteins in the pre- and post-denosumab samples. Using these profiles, the software program identified molecular interactions between the differentially expressed proteins that were indirectly involved in the RANK/RANKL pathway and in several non-canonical subpathways including the Matrix metalloproteinase pathway. The data analysis also suggested that the identified proteins play a critical functional role in the osteolytic process of GCTB. Among the most downregulated proteins, the activity of MMP-9 was significantly decreased in the denosumab-treated samples, although the residual stromal cells were found to express MMP-9 by an immunohistochemical analysis. The expression level of MMP-9 in the primary GCTB samples was not correlated with any clinicopathological factors, including patient outcomes. Although the replacement of tumors by fibro-osseous tissue or the diminishment of osteoclast-like giant cells have been shown as therapeutic effects of denosumab, the residual tumor after denosumab treatment, which is composed of only stromal cells, might be capable of causing bone destruction; thus the therapeutic application of denosumab would be still necessary for these lesions. We believe that the protein expression

  7. Eight proteins play critical roles in RCC with bone metastasis via mitochondrial dysfunction.

    PubMed

    Wang, Jiang; Zhao, Xiaolin; Qi, Jun; Yang, Caihong; Cheng, Hao; Ren, Ye; Huang, Lei

    2015-08-01

    Most kidney cancers are renal cell carcinomas (RCC). RCC lacks early warning signs and 70 % of patients with RCC develop metastases. Among them, 50 % of patients having skeletal metastases developed a dismal survival of less than 10 % at 5 years. Therefore, exploring the key driving proteins and pathways involved in RCC bone metastasis could benefit patients' therapy and prolong their survival. We examined the difference between the OS-RC-2 cells and the OS-RC-2-BM5 cells (subpopulation from OS-RC-2) of RCC with proteomics. Then we employed Western-blot, immunohistochemistry and the clinical database (oncomine) to screen and verify the key proteins and then we analyzed the functions and the related pathways of selected key proteins with system biology approaches. Our proteomic data revealed 26 significant changed spots (fold change <0.5 and >1.9, P < 0.05) between two cells. The Western blotting results validated for these identified spots were consistent with the proteomics'. From the public clinical database, 23 out of 26 proteins were connected with RCC metastases and 9 out of 23 with survival time directly (P < 0.05). Finally, only 8 out of 9 proteins had significantly positive results in tissues of RCC patients with bone metastasis compared with primary tumor (P < 0.05). System biology analyzing results showed these eight proteins mainly distributed in oxidative phosphorylation which indicates that mitochondria dysfunction played the critical role to regulate cells metastasis. Our article used a variety of experimental techniques to find eight proteins which abnormally regulated mitochondrial function to achieve a successful induction for RCC metastasis to bone.

  8. The controversy surrounding bone morphogenetic proteins in the spine: a review of current research.

    PubMed

    Hustedt, Joshua W; Blizzard, Daniel J

    2014-12-01

    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.

  9. 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

  10. The Emerging Role of MORC Family Proteins in Cancer Development and Bone Homeostasis.

    PubMed

    Hong, Guoju; Qiu, Heng; Wang, Chao; Jadhav, Gaurav; Wang, Haibin; Tickner, Jennifer; He, Wei; Xu, Jiake

    2017-05-01

    Microrchidia (MORC or MORC family CW-type zinc finger protein), a highly conserved nuclear protein superfamily, is an interesting new player in signaling-dependent chromatin remodeling and epigenetic regulation. MORC family proteins consist of MORC1, MORC2, MORC3, and MORC4 which display common structural determinants such as CW-type zinc finger and coiled-coil domains. They also exhibit unique structural motifs and tissue-specific expression profiles. MORC1 was first discovered as a key regulator for male meiosis and spermatogenesis. Accumulating biochemical and functional analyses unveil MORC proteins as key regulators for cancer development. More recently, using an ENU mutagenesis mouse model, MORC3 was found to play a role in regulating bone and calcium homeostasis. Here we discuss recent research progress on the emerging role of MORC proteins in cancer development and bone metabolism. Unravelling the cellular and molecular mechanisms by which MORC proteins carry out their functions in a tissue specific manner are important subjects for future investigation. J. Cell. Physiol. 232: 928-934, 2017. © 2016 Wiley Periodicals, Inc.

  11. Endogenous parathyroid hormone-related protein compensates for the absence of parathyroid hormone in promoting bone accrual in vivo in a model of bone marrow ablation.

    PubMed

    Zhu, Qi; Zhou, Xichao; Zhu, Min; Wang, Qian; Goltzman, David; Karaplis, Andrew; Miao, Dengshun

    2013-09-01

    To assess the effect of hypoparathyroidism on osteogenesis and bone turnover in vivo, bone marrow ablation (BMXs) were performed in tibias of 8-week-old wild-type and parathyroid hormone-null (PTH(-/-)) mice and newly formed bone tissue was analyzed from 5 days to 3 weeks after BMX. At 1 week after BMX, trabecular bone volume, osteoblast numbers, alkaline phosphatase-positive areas, type I collagen-positive areas, PTH receptor-positive areas, calcium sensing receptor-positive areas, and expression of bone formation-related genes were all decreased significantly in the diaphyseal regions of bones of PTH(-/-) mice compared to wild-type mice. In contrast, by 2 weeks after BMX, all parameters related to osteoblastic bone accrual were increased significantly in PTH(-/-) mice. At 5 days after BMX, active tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts had appeared in wild-type mice but were undetectable in PTH(-/-) mice, Both the ratio of mRNA levels of receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) and TRAP-positive osteoclast surface were still reduced in PTH(-/-) mice at 1 week but were increased by 2 weeks after BMX. The expression levels of parathyroid hormone-related protein (PTHrP) at both mRNA and protein levels were upregulated significantly at 1 week and more dramatically at 2 weeks after BMX in PTH(-/-) mice. To determine whether the increased newly formed bones in PTH(-/-) mice at 2 weeks after BMX resulted from the compensatory action of PTHrP, PTH(-/-) PTHrP(+/-) mice were generated and newly formed bone tissue was compared in these mice with PTH(-/-) and wild-type mice at 2 weeks after BMX. All parameters related to osteoblastic bone formation and osteoclastic bone resorption were reduced significantly in PTH(-/-) PTHrP(+/-) mice compared to PTH(-/-) mice. These results demonstrate that PTH deficiency itself impairs osteogenesis, osteoclastogenesis, and osteoclastic bone resorption, whereas subsequent upregulation of PTHr

  12. Nanofibrous yet injectable polycaprolactone-collagen bone tissue scaffold with osteoprogenitor cells and controlled release of bone morphogenetic protein-2.

    PubMed

    Subramanian, Gayathri; Bialorucki, Callan; Yildirim-Ayan, Eda

    2015-06-01

    In this work, we developed a nanofibrous, yet injectable orthobiologic tissue scaffold that is capable of hosting osteoprogenitor cells and controlling kinetic release profile of the encapsulated pro-osteogenic factor without diminishing its bioactivity over 21days. This innovative injectable scaffold was synthesized by incorporating electrospun and subsequently O2 plasma-functionalized polycaprolactone (PCL) nanofibers within the collagen type-I solution along with MC3T3-E1 cells (pre-osteoblasts) and bone morphogenetic protein-2 (BMP2). Through changing the PCL nanofiber concentration within the injectable scaffolds, we were able to tailor the mechanical strength, protein retention capacity, bioactivity preservation, and osteoinductive potential of the scaffolds. The nanofibrous internal structure of the scaffold allowed us to use a low dose of BMP2 (200ng/ml) to achieve osteoblastic differentiation in in vitro culture. The osteogenesis capacity of the injectable scaffolds were evaluated though measuring MC3T3-E1 cell proliferation, ALP activity, matrix mineralization, and early- and late-osteoblast specific gene expression profiles over 21days. The results demonstrated that the nanofibrous injectable scaffold provides not only an osteoinductive environment for osteoprogenitor cells to differentiate, but also a suitable biomechanical and biochemical environment to act as a reservoir for osteogenic factors with controlled release profile.

  13. Comparing the Effect of Nonactivated Platelet-Rich Plasma, Activated Platelet-Rich Plasma, and Bone Morphogenetic Protein-2 on Calvarial Bone Regeneration.

    PubMed

    Jeon, Yeo Reum; Jung, Bok Ki; Roh, Tai Suk; Kang, Eun Hye; Lee, Won Jai; Rah, Dong Kyun; Lew, Dae Hyun; Yun, In Sik

    2016-03-01

    Although platelet-rich plasma (PRP) is widely used to enhance bone graft survival, the effect of PRP itself on bone regeneration is unclear. Because activated PRP releases many growth factors in a bolus, there are controversies regarding the effect of activation of the PRP on bone regeneration. Thus, we studied the effect of activated versus nonactivated PRP on bone regeneration and compared the effect with that of recombinant human bone morphogenetic protein-2 (rhBMP-2) in a critical-sized cranial defect model. Forty New Zealand white rabbits were randomly divided into 4 groups. Defect sizing 15 × 15 mm(2) was created on the cranium of each rabbit, and then a collagen sponge soaked with normal saline, rhBMP-2, nonactivated PRP, or PRP activated with CaCl2 solution was immediately placed on the defect. After 16 weeks, using three-dimensional computed tomography and digital photography, the volume and new bone surface area were measured. The newly created bone was histologically analyzed. The experimental groups showed a significantly increased volume and surface area of new bone compared with the control group (P < 0.05), but no significant differences were found among the experimental groups. Histologic examination in the experimental groups showed newly created bone that had emerged in the center as well as the margin of the defect. Overall, these results indicate that PRP enhanced bony regeneration regardless of activation with an effect that was comparable to that of rhBMP-2. Thus, PRP has therapeutic effects on bone regeneration and may replace rhBMP-2, which is costly.

  14. Discoidin domain receptor 2 facilitates prostate cancer bone metastasis via regulating parathyroid hormone-related protein.

    PubMed

    Yan, Zhang; Jin, Su; Wei, Zhang; Huilian, Hou; Zhanhai, Yin; Yue, Teng; Juan, Li; Jing, Li; Libo, Yao; Xu, Li

    2014-09-01

    Prostate cancer frequently metastasizes to the skeleton but the underlying mechanism remains largely undefined. Discoidin domain receptor 2 (DDR2) is a member of receptor tyrosine kinase (RTK) family and is activated by collagen binding. This study aimed to investigate the function and detailed mechanism of DDR2 in prostate cancer bone dissemination. Herein we found that DDR2 was strongly expressed in bone-metastatic prostate cancer cells and tissues compared to that in normal controls. Enhanced expression of constitutively activated DDR2 led to elevation in motility and invasiveness of prostate cancer cells, whereas knockdown of DDR2 through specific shRNA caused a dramatic repression. Knockdown of DDR2 in prostate cancer cells resulted in significant decrease in the proliferation, differentiation and function of osteoblast. Over-expression of DDR2 in prostate cancer cells resulted in notable acceleration of osteoclast differentiation and bone resorption, whereas knockdown of DDR2 exhibited the opposite effects. An intrabone injection bone metastasis animal model demonstrated that DDR2 promoted osteolytic metastasis in vivo. Molecular evidence demonstrated that DDR2 regulated the expression, secretion, and promoter activity of parathyroid hormone-related protein (PTHrP), via modulating Runx2 phosphorylation and transactivity. DDR2 was responsive to TGF-β and involved in TGF-β-mediated osteoclast activation and bone resorption. In addition, DDR2 facilitated prostate cancer cells adhere to type I collagen. This study reveals for the first time that DDR2 plays an essential role in prostate cancer bone metastasis. The mechanism disclosure may provide therapeutic targets for the treatment of prostate cancer.

  15. Loss of Gi G-Protein-Coupled Receptor Signaling in Osteoblasts Accelerates Bone Fracture Healing.

    PubMed

    Wang, Liping; Hsiao, Edward C; Lieu, Shirley; Scott, Mark; O'Carroll, Dylan; Urrutia, Ashley; Conklin, Bruce R; Colnot, Celine; Nissenson, Robert A

    2015-10-01

    G-protein-coupled receptors (GPCRs) are key regulators of skeletal homeostasis and are likely important in fracture healing. Because GPCRs can activate multiple signaling pathways simultaneously, we used targeted disruption of G(i) -GPCR or activation of G(s) -GPCR pathways to test how each pathway functions in the skeleton. We previously demonstrated that blockade of G(i) signaling by pertussis toxin (PTX) transgene expression in maturing osteoblastic cells enhanced cortical and trabecular bone formation and prevented age-related bone loss in female mice. In addition, activation of G(s) signaling by expressing the G(s) -coupled engineered receptor Rs1 in maturing osteoblastic cells induced massive trabecular bone formation but cortical bone loss. Here, we test our hypothesis that the G(i) and G(s) pathways also have distinct functions in fracture repair. We applied closed, nonstabilized tibial fractures to mice in which endogenous G(i) signaling was inhibited by PTX, or to mice with activated G(s) signaling mediated by Rs1. Blockade of endogenous G(i) resulted in a smaller callus but increased bone formation in both young and old mice. PTX treatment decreased expression of Dkk1 and increased Lef1 mRNAs during fracture healing, suggesting a role for endogenous G(i) signaling in maintaining Dkk1 expression and suppressing Wnt signaling. In contrast, adult mice with activated Gs signaling showed a slight increase in the initial callus size with increased callus bone formation. These results show that G(i) blockade and G(s) activation of the same osteoblastic lineage cell can induce different biological responses during fracture healing. Our findings also show that manipulating the GPCR/cAMP signaling pathway by selective timing of G(s) and G(i) -GPCR activation may be important for optimizing fracture repair.

  16. 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.

  17. Preferential preservation of noncollagenous protein during bone diagenesis: Implications for chronometric and stable isotopic measurements

    NASA Astrophysics Data System (ADS)

    Masters, Patricia M.

    1987-12-01

    Preferential preservation of noncollagenous proteins (NCP) in diagenetically altered bone will affect amino acid compositions, inflate D/L aspartic acid ratios, and increase C/N ratios. Human skeletal remains representing both well preserved (collagenous) and diagenetically altered (noncollagenous) bones were selected from several southern California coastal archaeological sites that date from 8400 to 4100 years B.P. Amino acid compositions of the poorly preserved samples resembled NCP, which are probably retained by adsorption to the hydroxyapatite mineral phase of bone whereas collagen is degraded and lost to the environment over time. Since the racemization rate of aspartic acid in NCP is an order of magnitude faster than in collagen, the conservation of NCP in diagenetically altered bone can explain the high D/L aspartic acid ratios, and the erroneous Upper Pleistocene racemization ages calculated from these ratios, for several California Indian burials. Amino acid compositional analyses also indicated a non-amino acid source of nitrogen in the poorly preserved samples, which may account for their lower C/N ratios despite the acidic amino acid profiles typical of NCP. Preservation of NCP rather than collagen also precludes the extraction of a gelatin residue for radiocarbon dating and stable isotope analyses, but remnant NCP can yield apparently accurate radiocarbon dates. As collagen and phosphoprotein purified from a sample of modern human dentin have the same δ 13C and δ 15N values, remnant NCP may also be useful for paleodiet reconstructions based on stable carbon and nitrogen isotope compositions. Dentin collagen appears to be more resistant to diagenetic changes than does bone collagen. Consequently, dentin promises to be a more reliable material than bone for chronometric and stable isotope measurements.

  18. A meta analysis of lumbar spinal fusion surgery using bone morphogenetic proteins and autologous iliac crest bone graft.

    PubMed

    Zhang, Haifei; Wang, Feng; Ding, Lin; Zhang, Zhiyu; Sun, Deri; Feng, Xinmin; An, Jiuli; Zhu, Yue

    2014-01-01

    Bone morphogenetic protein (BMPs) as a substitute for iliac crest bone graft (ICBG) has been increasingly widely used in lumbar fusion. The purpose of this study is to systematically compare the effectiveness and safety of fusion with BMPs for the treatment of lumbar disease. Cochrane review methods were used to analyze all relevant randomized controlled trials (RCTs) published up to nov 2013. 19 RCTs (1,852 patients) met the inclusion criteria. BMPs group significantly increased fusion rate (RR: 1.13; 95% CI 1.05-1.23, P = 0.001), while there was no statistical difference in overall success of clinical outcomes (RR: 1.04; 95% CI 0.95-1.13, P = 0.38) and complications (RR: 0.96; 95% CI 0.85-1.09, p = 0.54). A significant reduction of the reoperation rate was found in BMPs group (RR: 0.57; 95% CI 0.42-0.77, p = 0.0002). Significant difference was found in the operating time (MD-0.32; 95% CI-0.55, -0.08; P = 0.009), but no significant difference was found in the blood loss, the hospital stay, patient satisfaction, and work status. Compared with ICBG, BMPs in lumbar fusion can increase the fusion rate, while reduce the reoperation rate and operating time. However, it doesn't increase the complication rate, the amount of blood loss and hospital stay. No significant difference was found in the overall success of clinical outcome of the two groups.

  19. A Meta Analysis of Lumbar Spinal Fusion Surgery Using Bone Morphogenetic Proteins and Autologous Iliac Crest Bone Graft

    PubMed Central

    Zhang, Haifei; Wang, Feng; Ding, Lin; Zhang, Zhiyu; Sun, Deri; Feng, Xinmin; An, Jiuli; Zhu, Yue

    2014-01-01

    Background Bone morphogenetic protein (BMPs) as a substitute for iliac crest bone graft (ICBG) has been increasingly widely used in lumbar fusion. The purpose of this study is to systematically compare the effectiveness and safety of fusion with BMPs for the treatment of lumbar disease. Methods Cochrane review methods were used to analyze all relevant randomized controlled trials (RCTs) published up to nov 2013. Results 19 RCTs (1,852 patients) met the inclusion criteria. BMPs group significantly increased fusion rate (RR: 1.13; 95% CI 1.05–1.23, P = 0.001), while there was no statistical difference in overall success of clinical outcomes (RR: 1.04; 95% CI 0.95–1.13, P = 0.38) and complications (RR: 0.96; 95% CI 0.85–1.09, p = 0.54). A significant reduction of the reoperation rate was found in BMPs group (RR: 0.57; 95% CI 0.42–0.77, p = 0.0002). Significant difference was found in the operating time (MD−0.32; 95% CI−0.55, −0.08; P = 0.009), but no significant difference was found in the blood loss, the hospital stay, patient satisfaction, and work status. Conclusion Compared with ICBG, BMPs in lumbar fusion can increase the fusion rate, while reduce the reoperation rate and operating time. However, it doesn’t increase the complication rate, the amount of blood loss and hospital stay. No significant difference was found in the overall success of clinical outcome of the two groups. PMID:24886911

  20. Autologous Morphogen Gradients by Subtle Interstitial Flow and Matrix Interactions

    PubMed Central

    Fleury, Mark E.; Boardman, Kendrick C.; Swartz, Melody A.

    2006-01-01

    Cell response to extracellular cues is often driven by gradients of morphogenetic and chemotactic proteins, and therefore descriptions of how such gradients arise are critical to understanding and manipulating these processes. Many of these proteins are secreted in matrix-binding form to be subsequently released proteolytically, and here we explore how this feature, along with small dynamic forces that are present in all tissues, can affect pericellular protein gradients. We demonstrate that 1), pericellular gradients of cell-secreted proteins can be greatly amplified when secreted by the cell in matrix-binding form as compared to a nonmatrix-interacting form; and 2), subtle flows can drive significant asymmetry in pericellular protein concentrations and create transcellular gradients that increase in the direction of flow. This study thus demonstrates how convection and matrix-binding, both physiological characteristics, combine to allow cells to create their own autologous chemotactic gradients that may drive, for example, tumor cells and immune cells into draining lymphatic capillaries. PMID:16603487

  1. Spaceflight has compartment- and gene-specific effects on mRNA levels for bone matrix proteins in rat femur

    NASA Technical Reports Server (NTRS)

    Evans, G. L.; Morey-Holton, E.; Turner, R. T.

    1998-01-01

    In the present study, we evaluated the possibility that the abnormal bone matrix produced during spaceflight may be associated with reduced expression of bone matrix protein genes. To test this possibility, we investigated the effects of a 14-day spaceflight (SLS-2 experiment) on steady-state mRNA levels for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), osteocalcin, osteonectin, and prepro-alpha(1) subunit of type I collagen in the major bone compartments of rat femur. There were pronounced site-specific differences in the steady-state levels of expression of the mRNAs for the three bone matrix proteins and GAPDH in normal weight-bearing rats, and these relationships were altered after spaceflight. Specifically, spaceflight resulted in decreases in mRNA levels for GAPDH (decreased in proximal metaphysis), osteocalcin (decreased in proximal metaphysis), osteonectin (decreased in proximal and distal metaphysis), and collagen (decreased in proximal and distal metaphysis) compared with ground controls. There were no changes in mRNA levels for matrix proteins or GAPDH in the shaft and distal epiphysis. These results demonstrate that spaceflight leads to site- and gene-specific decreases in mRNA levels for bone matrix proteins. These findings are consistent with the hypothesis that spaceflight-induced decreases in bone formation are caused by concomitant decreases in expression of genes for bone matrix proteins.

  2. Growth control by a moving morphogen gradient during Drosophila eye development.

    PubMed

    Wartlick, Ortrud; Jülicher, Frank; Gonzalez-Gaitan, Marcos

    2014-05-01

    During morphogenesis, organs grow to stereotyped sizes, but growth control mechanisms are poorly understood. Here, we measured the signaling dynamics of the morphogen Dpp, one of several Drosophila factors controlling morphogenetic growth, in the developing eye. In this tissue, the Dpp expression domain advances from the posterior to the anterior tissue edge. In front of this moving morphogen source, signaling inputs including Dpp activate the target gene hairy in a gradient that scales with tissue size. Proliferation, in turn, occurs in a mitotic wave in front of the source, whereas behind it, cells arrest and differentiate. We found that cells divide when their signaling levels have increased by around 60%. This simple mechanism quantitatively explains the proliferation and differentiation waves in wild type and mutants. Furthermore, this mechanism may be a common feature of different growth factors, because a Dpp-independent growth input also follows this growth rule.

  3. HOXA10 Controls Osteoblastogenesis by Directly Activating Bone Regulatory and Phenotypic Genes▿

    PubMed Central

    Hassan, Mohammad Q.; Tare, Rahul; Lee, Suk Hee; Mandeville, Matthew; Weiner, Brian; Montecino, Martin; van Wijnen, Andre J.; Stein, Janet L.; Stein, Gary S.; Lian, Jane B.

    2007-01-01

    HOXA10 is necessary for embryonic patterning of skeletal elements, but its function in bone formation beyond this early developmental stage is unknown. Here we show that HOXA10 contributes to osteogenic lineage determination through activation of Runx2 and directly regulates osteoblastic phenotypic genes. In response to bone morphogenic protein BMP2, Hoxa10 is rapidly induced and functions to activate the Runx2 transcription factor essential for bone formation. A functional element with the Hox core motif was characterized for the bone-related Runx2 P1 promoter. HOXA10 also activates other osteogenic genes, including the alkaline phosphatase, osteocalcin, and bone sialoprotein genes, and temporally associates with these target gene promoters during stages of osteoblast differentiation prior to the recruitment of RUNX2. Exogenous expression and small interfering RNA knockdown studies establish that HOXA10 mediates chromatin hyperacetylation and trimethyl histone K4 (H3K4) methylation of these genes, correlating to active transcription. HOXA10 therefore contributes to early expression of osteogenic genes through chromatin remodeling. Importantly, HOXA10 can induce osteoblast genes in Runx2 null cells, providing evidence for a direct role in mediating osteoblast differentiation independent of RUNX2. We propose that HOXA10 activates RUNX2 in mesenchymal cells, contributing to the onset of osteogenesis, and that HOXA10 subsequently supports bone formation by direct regulation of osteoblast phenotypic genes. PMID:17325044

  4. Transient Overexpression of Sonic Hedgehog Alters the Architecture and Mechanical Properties of Trabecular Bone

    PubMed Central

    Kiuru, Maija; Solomon, Jason; Ghali, Bassem; van der Meulen, Marjolein; Crystal, Ronald G; Hidaka, Chisa

    2009-01-01

    Bone formation and remodeling involve coordinated interactions between osteoblasts and osteoclasts through signaling networks involving a variety of molecular pathways. We hypothesized that overexpression of Sonic hedgehog (Shh), a morphogen with a crucial role in skeletal development, would stimulate osteoblastogenesis and bone formation in adult animals in vivo. Systemic administration of adenovirus expressing the N-terminal form of Shh into adult mice resulted in a primary increase in osteoblasts and their precursors. Surprisingly, however, this was associated with altered trabecular morphology, decreased bone volume, and decreased compressive strength in the vertebrae. Whereas no change was detected in the number of osteoclast precursors, bone marrow stromal cells from Shh-treated mice showed enhanced osteoclastogenic potential in vitro. These effects were mediated by the PTH/PTH-related protein (PTHrP) pathway as evidenced by increased sensitivity to PTH stimulation and upregulation of the PTH/PTHrP receptor (PPR). Together, these data show that Shh has stimulatory effects on osteoprogenitors and osteoblasts in adult animals in vivo, which results in bone remodeling and reduced bone strength because of a secondary increase in osteoclastogenesis. PMID:19338448

  5. Proteomic analysis of a pleistocene mammoth femur reveals more than one hundred ancient bone proteins.

    PubMed

    Cappellini, Enrico; Jensen, Lars J; Szklarczyk, Damian; Ginolhac, Aurélien; da Fonseca, Rute A R; Stafford, Thomas W; Holen, Steven R; Collins, Matthew J; Orlando, Ludovic; Willerslev, Eske; Gilbert, M Thomas P; Olsen, Jesper V

    2012-02-03

    We used high-sensitivity, high-resolution tandem mass spectrometry to shotgun sequence ancient protein remains extracted from a 43 000 year old woolly mammoth ( Mammuthus primigenius ) bone preserved in the Siberian permafrost. For the first time, 126 unique protein accessions, mostly low-abundance extracellular matrix and plasma proteins, were confidently identified by solid molecular evidence. Among the best characterized was the carrier protein serum albumin, presenting two single amino acid substitutions compared to extant African ( Loxodonta africana ) and Indian ( Elephas maximus ) elephants. Strong evidence was observed of amino acid modifications due to post-mortem hydrolytic and oxidative damage. A consistent subset of this permafrost bone proteome was also identified in more recent Columbian mammoth ( Mammuthus columbi ) samples from temperate latitudes, extending the potential of the approach described beyond subpolar environments. Mass spectrometry-based ancient protein sequencing offers new perspectives for future molecular phylogenetic inference and physiological studies on samples not amenable to ancient DNA investigation. This approach therefore represents a further step into the ongoing integration of different high-throughput technologies for identification of ancient biomolecules, unleashing the field of paleoproteomics.

  6. ASSOCIATIONS OF PROTEIN INTAKE AND PROTEIN SOURCE WITH BONE MINERAL DENSITY AND FRACTURE RISK: A POPULATION-BASED COHORT STUDY

    PubMed Central

    LANGSETMO, L.; BARR, S.I.; BERGER, C.; KREIGER, N.; RAHME, E.; ADACHI, J.D.; PAPAIOANNOU, A.; KAISER, S. M; PRIOR, J.C.; HANLEY, D.A.; KOVACS, C.S.; JOSSE, R.G.; GOLTZMAN, D.

    2016-01-01

    High dietary protein has been hypothesized to cause lower bone mineral density (BMD) and greater fracture risk. Previous results are conflicting and few studies have assessed potential differences related to differing protein sources. Objective To determine associations between total protein intake, and protein intake by source (dairy, non-dairy animal, plant) with BMD, BMD change, and incident osteoporotic fracture. Design/Setting Prospective cohort study (Canadian Multicentre Osteoporosis Study). Participants/Measures Protein intake was assessed as percent of total energy intake (TEI) at Year 2 (1997–99) using a food frequency questionnaire (N=6510). Participants were contacted annually to ascertain incident fracture. Total hip and lumbar spine BMD was measured at baseline and Year 5. Analyses were stratified by group (men 25–49 y, men 50+ y, premenopausal women 25–49 y, and postmenopausal women 50+ y) and adjusted for major confounders. Fracture analyses were limited to those 50+ y. Results Intakes of dairy protein (with adjustment for BMI) were positively associated with total hip BMD among men and women aged 50+ y, and in men aged 25–49. Among adults aged 50+ y, those with protein intakes of <12% TEI (women) and <11% TEI (men) had increased fracture risk compared to those with intakes of 15% TEI. Fracture risk did not significantly change as intake increased above 15% TEI, and was not significantly associated with protein source. Conclusions In contrast to hypothesized risk of high protein, we found that for adults 50+ y, low protein intake (below 15% TEI) may lead to increased fracture risk. Source of protein was a determinant of BMD, but not fracture risk. PMID:26412291

  7. 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

  8. Intrinsic Noise Profoundly Alters the Dynamics and Steady State of Morphogen-Controlled Bistable Genetic Switches

    PubMed Central

    Page, Karen M.

    2016-01-01

    During tissue development, patterns of gene expression determine the spatial arrangement of cell types. In many cases, gradients of secreted signalling molecules—morphogens—guide this process by controlling downstream transcriptional networks. A mechanism commonly used in these networks to convert the continuous information provided by the gradient into discrete transitions between adjacent cell types is the genetic toggle switch, composed of cross-repressing transcriptional determinants. Previous analyses have emphasised the steady state output of these mechanisms. Here, we explore the dynamics of the toggle switch and use exact numerical simulations of the kinetic reactions, the corresponding Chemical Langevin Equation, and Minimum Action Path theory to establish a framework for studying the effect of gene expression noise on patterning time and boundary position. This provides insight into the time scale, gene expression trajectories and directionality of stochastic switching events between cell states. Taking gene expression noise into account predicts that the final boundary position of a morphogen-induced toggle switch, although robust to changes in the details of the noise, is distinct from that of the deterministic system. Moreover, the dramatic increase in patterning time close to the boundary predicted from the deterministic case is substantially reduced. The resulting stochastic switching introduces differences in patterning time along the morphogen gradient that result in a patterning wave propagating away from the morphogen source with a velocity determined by the intrinsic noise. The wave sharpens and slows as it advances and may never reach steady state in a biologically relevant time. This could explain experimentally observed dynamics of pattern formation. Together the analysis reveals the importance of dynamical transients for understanding morphogen-driven transcriptional networks and indicates that gene expression noise can qualitatively

  9. Controversies Surrounding High-Protein Diet Intake: Satiating Effect and Kidney and Bone Health12

    PubMed Central

    Cuenca-Sánchez, Marta; Navas-Carrillo, Diana; Orenes-Piñero, Esteban

    2015-01-01

    Long-term consumption of a high-protein diet could be linked with metabolic and clinical problems, such as loss of bone mass and renal dysfunction. However, although it is well accepted that a high-protein diet may be detrimental to individuals with existing kidney dysfunction, there is little evidence that high protein intake is dangerous for healthy individuals. High-protein meals and foods are thought to have a greater satiating effect than high-carbohydrate or high-fat meals. The effect of high-protein diets on the modulation of satiety involves multiple metabolic pathways. Protein intake induces complex signals, with peptide hormones being released from the gastrointestinal tract and blood amino acids and derived metabolites being released in the blood. Protein intake also stimulates metabolic hormones that communicate information about energy status to the brain. Long-term ingestion of high amounts of protein seems to decrease food intake, body weight, and body adiposity in many well-documented studies. The aim of this article is to provide an extensive overview of the efficacy of high protein consumption in weight loss and maintenance, as well as the potential consequences in human health of long-term intake. PMID:25979491

  10. Controversies surrounding high-protein diet intake: satiating effect and kidney and bone health.

    PubMed

    Cuenca-Sánchez, Marta; Navas-Carrillo, Diana; Orenes-Piñero, Esteban

    2015-05-01

    Long-term consumption of a high-protein diet could be linked with metabolic and clinical problems, such as loss of bone mass and renal dysfunction. However, although it is well accepted that a high-protein diet may be detrimental to individuals with existing kidney dysfunction, there is little evidence that high protein intake is dangerous for healthy individuals. High-protein meals and foods are thought to have a greater satiating effect than high-carbohydrate or high-fat meals. The effect of high-protein diets on the modulation of satiety involves multiple metabolic pathways. Protein intake induces complex signals, with peptide hormones being released from the gastrointestinal tract and blood amino acids and derived metabolites being released in the blood. Protein intake also stimulates metabolic hormones that communicate information about energy status to the brain. Long-term ingestion of high amounts of protein seems to decrease food intake, body weight, and body adiposity in many well-documented studies. The aim of this article is to provide an extensive overview of the efficacy of high protein consumption in weight loss and maintenance, as well as the potential consequences in human health of long-term intake.

  11. Immunolocalization of heat shock protein 27 in developing jaw bones and tooth germs of human fetuses.

    PubMed

    Leonardi, R; Barbato, E; Paganelli, C; Lo Muzio, L

    2004-12-01

    27 kDa Heat shock protein (Hsp27), which is also identified as p29 estrogen-receptor associated protein, plays a crucial role in specific growth stages. It also seems to be involved in the balance between differentiation and apoptosis. To determine whether Hsp27 is involved during craniofacial development and odontogenesis, its expression was studied through immunohistochemistry of developing jaw bone as well as the odontogenesis of heads from human fetuses. Formalin-fixed paraffin-embedded specimens of 7 human fetuses (3 female, 4 male), obtained from miscarriages occurring between the 9th and 16th weeks of pregnancy, were examined by using a monoclonal antibody against Hsp27. Staining intensity (weak, +; moderate, ++; strong, +++) was evaluated semiquantitatively. The sample slice was cut through a coronal plane, which included eyes, nasal cavities, tongue, and primitive dental lamina with tooth germs. A transient and spatially restricted expression of Hsp27 in developing human jaw bones and teeth was observed. Osteoblasts around the uncalcified bone matrix showed Hsp27 immunoreaction products (+++), whereas osteocytes were not immunolabeled. In mandibular condyle, immunolabeling was restricted to hypertrophic chondrocytes (++). In developing tooth germs, Hsp27 immunostaining was detected throughout the bud (+++). At the early cap stage, a strong immunolabeling for Hsp27 was seen in the dental lamina (+++), and a moderate staining was seen in the outer dental epithelium (++). At the late cap stage, Hsp27 expression was detected in the outer dental epithelium (++) as well as in the cells of the future stellate reticulum (++). The spatiotemporal-restricted expression of Hsp27 in craniofacial bones during development suggests that this protein could be involved in the balance between differentiation and apoptosis, by modulating the viability of osteoblasts and chondrocytes. The specific regional and temporal expression patterns of Hsp27 during tooth development

  12. A high dairy protein, high-calcium diet minimizes bone turnover in overweight adults during weight loss.

    PubMed

    Bowen, Jane; Noakes, Manny; Clifton, Peter M

    2004-03-01

    Weight loss induces bone resorption and this can be attenuated by calcium supplementation. Protein-rich diets were recently associated with favorable effects on bone density, although this remains controversial. We hypothesized that a diet high in calcium and protein would minimize bone resorption during weight loss compared with a lower calcium, protein-rich diet. The effects of dietary calcium in high protein diets on calcium excretion and bone metabolism were examined in overweight adults (n = 50, BMI 33.4 +/- 2.1 kg/m(2)) during 12 wk of energy restriction followed by 4 wk of energy balance. Subjects were randomly assigned to isoenergetic diets (5.5 MJ/d, 34% energy from protein, 41% carbohydrate, 24% fat) high in either dairy protein (DP, 2400 mg Ca/d) or mixed protein sources (MP, 500 mg Ca/d). During energy restriction, weight loss was 10% (-9.7 +/- 3.8 kg, P < 0.01), and 24-h urinary calcium excretion decreased independently of diet (-1.09 +/- 0.23 mmol/d, P < 0.01). By wk 16, the MP diet group had a 40% greater increase in deoxypyridinoline (bone resorption marker) than the DP diet group (P = 0.008). Osteocalcin (bone formation marker) increased from wk 0 to 16 in only the MP diet group [+2.16 +/- 0.63 micro g/L (+0.63 +/- 0.11nmol/L), P = 0.001]. In conclusion, weight loss was associated with increased bone resorption, yet the DP diet had a modest advantage over the MP diet by minimizing overall turnover. Combined with reduced urinary calcium excretion, this suggests that a high-protein, calcium-replete diet may protect against bone loss during weight reduction.

  13. 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.

  14. Improved bone morphogenetic protein-2 retention in an injectable collagen matrix using bifunctional peptides.

    PubMed

    Hamilton, Paul T; Jansen, Michelle S; Ganesan, Sathya; Benson, R Edward; Hyde-Deruyscher, Robin; Beyer, Wayne F; Gile, Joseph C; Nair, Shrikumar A; Hodges, Jonathan A; Grøn, Hanne

    2013-01-01

    To promote healing of many orthopedic injuries, tissue engineering approaches are being developed that combine growth factors such as Bone Morphogenetic Proteins (BMP) with biomaterial carriers. Although these technologies have shown great promise, they still face limitations. We describe a generalized approach to create target-specific modular peptides that bind growth factors to implantable biomaterials. These bifunctional peptide coatings provide a novel way to modulate biology on the surface of an implant. Using phage display techniques, we have identified peptides that bind with high affinity to BMP-2. The peptides that bind to BMP-2 fall into two different sequence clusters. The first cluster of peptide sequences contains the motif W-X-X-F-X-X-L (where X can be any amino acid) and the second cluster contains the motif F-P-L-K-G. We have synthesized bifunctional peptide linkers that contain BMP-2 and collagen-binding domains. Using a rat ectopic bone formation model, we have injected rhBMP-2 into a collagen matrix with or without a bifunctional BMP-2: collagen peptide (BC-1). The presence of BC-1 significantly increased osteogenic cellular activity, the area of bone formed, and bone maturity at the site of injection. Our results suggest that bifunctional peptides that can simultaneously bind to a growth factor and an implantable biomaterial can be used to control the delivery and release of growth factors at the site of implantation.

  15. Effects of high-protein intake on bone turnover in long-term bed rest in women.

    PubMed

    Heer, Martina; Baecker, Natalie; Frings-Meuthen, Petra; Graf, Sonja; Zwart, Sara R; Biolo, Gianni; Smith, Scott M

    2017-01-19

    Bed rest (BR) causes bone loss, even in otherwise healthy subjects. Several studies suggest that ambulatory subjects may benefit from high-protein intake to stimulate protein synthesis and to maintain muscle mass. However, increasing protein intake above the recommended daily intake without adequate calcium and potassium intake may increase bone resorption. We hypothesized that a regimen of high-protein intake (HiPROT), applied in an isocaloric manner during BR, with calcium and potassium intake meeting recommended values, would prevent any effect of BR on bone turnover. After a 20-day ambulatory adaptation to a controlled environment, 16 women participated in a 60-day, 6° head-down-tilt (HDT) BR and were assigned randomly to 1 of 2 groups. Control (CON) subjects (n = 8) received 1 g/(kg body mass·day)(-1) dietary protein. HiPROT subjects (n = 8) received 1.45 g protein/(kg body mass·day)(-1) plus an additional 0.72 g branched-chain amino acids per day during BR. All subjects received an individually tailored diet (before HDTBR: 1888 ± 98 kcal/day; during HDTBR: 1604 ± 125 kcal/day; after HDTBR: 1900 ± 262 kcal/day), with the CON group's diet being higher in fat and carbohydrate intake. High-protein intake exacerbated the BR-induced increase in bone resorption marker C-telopeptide (>30%) (p < 0.001) by the end of BR. Bone formation markers were unaffected by BR and high-protein intake. We conclude that high-protein intake in BR might increase bone loss. Further long-duration studies are mandatory to show how the positive effect of protein on muscle mass can be maintained without the risk of reducing bone mineral density.

  16. Role of ID Proteins in BMP4 Inhibition of Profibrotic Effects of TGF-β2 in Human TM Cells

    PubMed Central

    Mody, Avani A.; Wordinger, Robert J.; Clark, Abbot F.

    2017-01-01

    Purpose Increased expression of TGF-β2 in primary open-angle glaucoma (POAG) aqueous humor (AH) and trabecular meshwork (TM) causes deposition of extracellular matrix (ECM) in the TM and elevated IOP. Bone morphogenetic proteins (BMPs) regulate TGF-β2–induced ECM production. The underlying mechanism for BMP4 inhibition of TGF-β2–induced fibrosis remains undetermined. Bone morphogenic protein 4 induces inhibitor of DNA binding proteins (ID1, ID3), which suppress transcription factor activities to regulate gene expression. Our study will determine whether ID1and ID3 proteins are downstream targets of BMP4, which attenuates TGF-β2 induction of ECM proteins in TM cells. Methods Primary human TM cells were treated with BMP4, and ID1 and ID3 mRNA, and protein expression was determined by quantitative PCR (Q-PCR) and Western immunoblotting. Intracellular ID1 and ID3 protein localization was studied by immunocytochemistry. Transformed human TM cells (GTM3 cells) were transfected with ID1 or ID3 expression vectors to determine their potential inhibitory effects on TGF-β2–induced fibronectin and plasminogen activator inhibitor-I (PAI-1) protein expression. Results Basal expression of ID1-3 was detected in primary human TM cells. Bone morphogenic protein 4 significantly induced early expression of ID1 and ID3 mRNA (P < 0.05) and protein in primary TM cells, and a BMP receptor inhibitor blocked this induction. Overexpression of ID1 and ID3 significantly inhibited TGF-β2–induced expression of fibronectin and PAI-1 in TM cells (P < 0.01). Conclusions Bone morphogenic protein 4 induced ID1 and ID3 expression suppresses TGF-β2 profibrotic activity in human TM cells. In the future, targeting specific regulators may control the TGF-β2 profibrotic effects on the TM, leading to disease modifying IOP lowering therapies. PMID:28159972

  17. JAK/STAT controls organ size and fate specification by regulating morphogen production and signalling

    PubMed Central

    Recasens-Alvarez, Carles; Ferreira, Ana; Milán, Marco

    2017-01-01

    A stable pool of morphogen-producing cells is critical for the development of any organ or tissue. Here we present evidence that JAK/STAT signalling in the Drosophila wing promotes the cycling and survival of Hedgehog-producing cells, thereby allowing the stable localization of the nearby BMP/Dpp-organizing centre in the developing wing appendage. We identify the inhibitor of apoptosis dIAP1 and Cyclin A as two critical genes regulated by JAK/STAT and contributing to the growth of the Hedgehog-expressing cell population. We also unravel an early role of JAK/STAT in guaranteeing Wingless-mediated appendage specification, and a later one in restricting the Dpp-organizing activity to the appendage itself. These results unveil a fundamental role of the conserved JAK/STAT pathway in limb specification and growth by regulating morphogen production and signalling, and a function of pro-survival cues and mitogenic signals in the regulation of the pool of morphogen-producing cells in a developing organ. PMID:28045022

  18. A microparticle approach to morphogen delivery within pluripotent stem cell aggregates

    PubMed Central

    Bratt-Leal, Andrés M.; Nguyen, Anh H.; Hammersmith, Katy A.; Singh, Ankur; McDevitt, Todd C.

    2013-01-01

    Stem cell fate and specification is largely controlled by extrinsic cues that comprise the 3D microenvironment. Biomaterials can serve to control the spatial and temporal presentation of morphogenic molecules in order to direct stem cell fate decisions. Here we describe a microparticle (MP)-based approach to deliver growth factors within multicellular aggregates to direct pluripotent stem cell differentiation. Compared to conventional soluble delivery methods, gelatin MPs laden with BMP4 or noggin induced efficient gene expression of mesoderm and ectoderm lineages, respectively, despite using nearly 12-fold less total growth factor. BMP4-laden MPs increased the percentage of cells expressing GFP under the control of the Brachyury-T promoter as visualized by whole-mount confocal imaging and quantified by flow cytometry. Furthermore, the ability to localize MPs laden with different morphogens within a particular hemisphere of stem cell aggregates allowed for spatial control of differentiation within 3D cultures. Overall, localized delivery of growth factors within multicellular aggregates from microparticle delivery vehicles is an important step towards scalable differentiation technologies and the study of morphogen gradients in pluripotent stem cell differentiation. PMID:23827184

  19. Current perspectives on parathyroid hormone (PTH) and PTH-related protein (PTHrP) as bone anabolic therapies.

    PubMed

    Esbrit, Pedro; Alcaraz, María José

    2013-05-15

    Osteoporosis is characterized by low bone mineral density and/or poor bone microarchitecture leading to an increased risk of fractures. The skeletal alterations in osteoporosis are a consequence of a relative deficit of bone formation compared to bone resorption. Osteoporosis therapies have mostly relied on antiresorptive drugs. An alternative therapeutic approach for osteoporosis is currently available, based on the intermittent administration of parathyroid hormone (PTH). Bone anabolism caused by PTH therapy is mainly accounted for by the ability of PTH to increase osteoblastogenesis and osteoblast survival. PTH and PTH-related protein (PTHrP)-an abundant local factor in bone- interact with the common PTH type 1 receptor with similar affinities in osteoblasts. Studies mainly in osteoporosis rodent models and limited data in postmenopausal women suggest that N-terminal PTHrP peptides might be considered a promising bone anabolic therapy. In addition, putative osteogenic actions of PTHrP might be ascribed not only to its N-terminal domain but also to its PTH-unrelated C-terminal region. In this review, we discuss the underlying cellular and molecular mechanisms of the anabolic actions of PTH and the similar potential of PTH-related protein (PTHrP) to increase bone mass and improve bone regeneration. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Data supporting regulating temporospatial dynamics of morphogen for structure formation of the lacrimal gland by chitosan biomaterials.

    PubMed

    Hsiao, Ya-Chuan; Yang, Tsung-Lin

    2017-02-01

    The lacrimal gland is responsible for tear synthesis and secretion, and is derived from the epithelia of ocular surface and generated by branching morphogenesis. The dataset presented in this article is to support the research results of the effect of chitosan biomaterials on facilitating the structure formation of the lacrimal gland by regulating temporospatial dynamics of morphogen. The embryonic lacrimal gland explants were used as the standard experimental model for investigating lacrimal gland branching morphogenesis. Chitosan biomaterials promoted lacrimal gland branching with a dose-dependent effect. It helped in vivo binding of hepatocyte growth factor (HGF) related molecules in the epithelial-mesenchymal boundary of emerging epithelial branches. When mitogen-activated protein kinase (MAPK) or protein kinase B (Akt/PKB) inhibitors applied, the chitosan effects reduced. Nonetheless, the ratios of MAPK and Akt/PKB phosphorylation were still greater in the chitosan group than the control. The data demonstrated here confirm the essential role of HGF-signaling in chitosan-promoted structure formation of the lacrimal gland.

  1. A low protein diet alters bone material level properties and the response to in vitro repeated mechanical loading.

    PubMed

    Dubois-Ferrière, Victor; Rizzoli, René; Ammann, Patrick

    2014-01-01

    Low protein intake is associated with an alteration of bone microstructure and material level properties. However, it remains unknown whether these alterations of bone tissue could influence the response to repeated mechanical loading. The authors investigated the in vitro effect of repeated loading on bone strength in humeri collected from 20 6-month-old female rats pair-fed with a control (15% casein) or an isocaloric low protein (2.5% casein) diet for 10 weeks. Bone specimens were cyclically loaded in three-point bending under load control for 2000 cycles. Humeri were then monotonically loaded to failure. The load-displacement curve of the in vitro cyclically loaded humerus was compared to the contralateral noncyclically loaded humerus and the influence of both protein diets. Material level properties were also evaluated through a nanoindentation test. Cyclic loading decreased postyield load and plastic deflection in rats fed a low protein diet, but not in those on a regular diet. Bone material level properties were altered in rats fed a low protein diet. This suggests that bone biomechanical alterations consequent to cyclic loading are more likely to occur in rats fed a low protein diet than in control animals subjected to the same in vitro cyclic loading regimen.

  2. Combined effects of soy isoflavones and milk basic protein on bone mineral density in hind-limb unloaded mice

    PubMed Central

    Matsumoto, Yu; Tousen, Yuko; Nishide, Yoriko; Tadaishi, Miki; Kato, Ken; Ishimi, Yoshiko

    2016-01-01

    We examined whether the combination of isoflavone and milk basic protein both are reported to be effective for bone metabolism, prevents bone loss induced by skeletal hind-limb unloading in mice. Female ddY strain mice, aged 8 weeks, were divided into six groups (n = 6–8 each): (1) normally housed group, (2) loading group, (3) hind-limb unloading group fed a control diet, (4) hind-limb unloading group fed a 0.2% isoflavone conjugates diet, (5) hind-limb unloading group fed a 1.0% milk basic protein diet, and (6) hind-limb unloading group fed a 0.2% isoflavone conjugates and 1.0% milk basic protein diet. After 3 weeks, femoral bone mineral density was markedly reduced in unloading mice. The combination of isoflavone and milk basic protein showed cooperative effects in preventing bone loss and milk basic protein inhibited the increased expression of osteogenic genes in bone marrow cells in unloading mice. These results suggest that the combination of soy isoflavone and milk basic protein may be useful for bone health in subjects with disabling conditions as well as astronauts. PMID:27013781

  3. Using poly(lactic-co-glycolic acid) microspheres to encapsulate plasmid of bone morphogenetic protein 2/polyethylenimine nanoparticles to promote bone formation in vitro and in vivo.

    PubMed

    Qiao, Chunyan; Zhang, Kai; Jin, Han; Miao, Leiying; Shi, Ce; Liu, Xia; Yuan, Anliang; Liu, Jinzhong; Li, Daowei; Zheng, Changyu; Zhang, Guirong; Li, Xiangwei; Yang, Bai; Sun, Hongchen

    2013-01-01

    Repair of large bone defects is a major challenge, requiring sustained stimulation to continually promote bone formation locally. Bone morphogenetic protein 2 (BMP-2) plays an important role in bone development. In an attempt to overcome this difficulty of bone repair, we created a delivery system to slowly release human BMP-2 cDNA plasmid locally, efficiently transfecting local target cells and secreting functional human BMP-2 protein. For transfection, we used polyethylenimine (PEI) to create pBMP-2/PEI nanoparticles, and to ensure slow release we used poly(lactic-co-glycolic acid) (PLGA) to create microsphere encapsulated pBMP-2/PEI nanoparticles, PLGA@pBMP-2/PEI. We demonstrated that pBMP-2/PEI nanoparticles could slowly release from the PLGA@pBMP-2/PEI microspheres for a long period of time. The 3-15 μm diameter of the PLGA@pBMP-2/PEI further supported this slow release ability of the PLGA@pBMP-2/PEI. In vitro transfection assays demonstrated that pBMP-2/PEI released from PLGA@pBMP-2/PEI could efficiently transfect MC3T3-E1 cells, causing MC3T3-E1 cells to secrete human BMP-2 protein, increase calcium deposition and gene expressions of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), SP7 and I type collagen (COLL I), and finally induce MC3T3-E1 cell differentiation. Importantly, in vivo data from micro-computed tomography (micro-CT) and histological staining demonstrated that the human BMP-2 released from PLGA@pBMP-2/PEI had a long-term effect locally and efficiently promoted bone formation in the bone defect area compared to control animals. All our data suggest that our PLGA-nanoparticle delivery system efficiently and functionally delivers the human BMP-2 cDNA and has potential clinical application in the future after further modification.

  4. 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.

  5. Effects of Osseointegration by Bone Morphogenetic Protein-2 on Titanium Implants In Vitro and In Vivo

    PubMed Central

    Teng, Fu-Yuan; Chen, Wen-Cheng; Wang, Yin-Lai; Hung, Chun-Cheng; Tseng, Chun-Chieh

    2016-01-01

    This study designed a biomimetic implant for reducing healing time and achieving early osseointegration to create an active surface. Bone morphogenetic protein-2 (BMP-2) is a strong regulator protein in osteogenic pathways. Due to hardly maintaining BMP-2 biological function and specificity, BMP-2 efficient delivery on implant surfaces is the main challenge for the clinic application. In this study, a novel method for synthesizing functionalized silane film for superior modification with BMP-2 on titanium surfaces is proposed. Three groups were compared with and without BMP-2 on modified titanium surfaces in vitro and in vivo: mechanical grinding; electrochemical modification through potentiostatic anodization (ECH); and sandblasting, alkali heating, and etching (SMART). Cell tests indicated that the ECH and SMART groups with BMP-2 markedly promoted D1 cell activity and differentiation compared with the groups without BMP-2. Moreover, the SMART group with a BMP-2 surface markedly promoted early alkaline phosphatase expression in the D1 cells compared with the other surface groups. Compared with these groups in vivo, SMART silaning with BMP-2 showed superior bone quality and created contact areas between implant and surrounding bones. The SMART group with BMP-2 could promote cell mineralization in vitro and osseointegration in vivo, indicating potential clinical use. PMID:26977141

  6. Conditional expression of human bone Gla protein in osteoblasts causes skeletal abnormality in mice.

    PubMed

    Ikeda, Kazuhiro; Tsukui, Tohru; Tanaka, Daisuke; Maruyama, Yojiro; Horie-Inoue, Kuniko; Inoue, Satoshi

    2012-07-20

    Bone Gla protein (BGP), also known as osteocalcin, is one of the most abundant γ-carboxylated noncollagenous protein in bone matrix and plays important roles in mineralization and calcium ion homeostasis. BGP is synthesized specifically in osteoblasts; however, its precise function in bone metabolism has not been fully elucidated. To investigate the in vivo function of human BGP (hBGP), we generated CAG-GFP(floxed)-hBGP transgenic mice carrying a transgene cassette composed of the promoter and a floxed GFP linked to hBGP cDNA. The mice were crossed with ColI-Cre mice, which express the Cre recombinase driven by the mouse collagen type 1a1 gene promoter, to obtain hBGP(ColI) conditional transgenic mice that expressed human BGP in osteoblasts. The hBGP(ColI) mice did not survive more than 2days after birth. The analysis of the 18.5-day post coitum fetuses of the hBGP(ColI) mice revealed that they displayed abnormal skeletal growth such as deformity of the rib and short femur and cranium lengths. Moreover, increased BGP levels were detected in the serum of the neonates. These findings indicate that hBGP expression in osteoblasts resulted in the abnormal skeletal growth in the mice. Our study provides a valuable model for understanding the fundamental role of BGP in vivo. Copyright © 2012. Published by Elsevier Inc.

  7. Differential effects and glucocorticoid potentiation of bone morphogenetic protein action during rat osteoblast differentiation in vitro.

    PubMed

    Boden, S D; McCuaig, K; Hair, G; Racine, M; Titus, L; Wozney, J M; Nanes, M S

    1996-08-01

    Bone morphogenetic proteins (BMPs) induce cartilage and bone differentiation in vivo and promote osteoblast differentiation from calvarial and marrow stromal cell preparations. Functional differences between BMP-2, -4, and -6 are not well understood. Recent investigations find that these three closely related osteoinductive proteins may exert different effects in primary rat calvarial cell cultures, suggesting the possibility of unique functions in vivo. In this study, we use a fetal rat secondary calvarial cell culture system to examine the differential effects of BMP-2, -4, and -6 on early osteoblast differentiation. These cells do not spontaneously differentiate into osteoblasts, as do cells in primary calvarial cultures, but rather require exposure to a differentiation initiator such as glucocorticoid or BMP. We determined that BMP-6 is a 2- to 2.5-fold more potent inducer of osteoblast differentiation than BMP-2 or -4. BMP-6 induced the formation of more and larger bone nodules as well as increased osteocalcin secretion. The effects of all three of these BMPs were potentiated up to 10-fold by cotreatment or pretreatment with the glucocorticoid triamcinolone (Trm). The Trm effects were synergistic with those of BMP-2 or -4, suggesting that this glucocorticoid may increase the cell responsiveness to these BMPs. Finally, BMP-6 did not require either cotreatment or pretreatment with Trm to achieve greater amounts of osteoblast differentiation than seen with BMP-2 or BMP-4 treatment, suggesting that BMP-6 may act at an earlier stage of cell differentiation.

  8. Effects of Osseointegration by Bone Morphogenetic Protein-2 on Titanium Implants In Vitro and In Vivo.

    PubMed

    Teng, Fu-Yuan; Chen, Wen-Cheng; Wang, Yin-Lai; Hung, Chun-Cheng; Tseng, Chun-Chieh

    2016-01-01

    This study designed a biomimetic implant for reducing healing time and achieving early osseointegration to create an active surface. Bone morphogenetic protein-2 (BMP-2) is a strong regulator protein in osteogenic pathways. Due to hardly maintaining BMP-2 biological function and specificity, BMP-2 efficient delivery on implant surfaces is the main challenge for the clinic application. In this study, a novel method for synthesizing functionalized silane film for superior modification with BMP-2 on titanium surfaces is proposed. Three groups were compared with and without BMP-2 on modified titanium surfaces in vitro and in vivo: mechanical grinding; electrochemical modification through potentiostatic anodization (ECH); and sandblasting, alkali heating, and etching (SMART). Cell tests indicated that the ECH and SMART groups with BMP-2 markedly promoted D1 cell activity and differentiation compared with the groups without BMP-2. Moreover, the SMART group with a BMP-2 surface markedly promoted early alkaline phosphatase expression in the D1 cells compared with the other surface groups. Compared with these groups in vivo, SMART silaning with BMP-2 showed superior bone quality and created contact areas between implant and surrounding bones. The SMART group with BMP-2 could promote cell mineralization in vitro and osseointegration in vivo, indicating potential clinical use.

  9. Improved binding of acidic bone matrix proteins to cationized filters during solid phase assays.

    PubMed

    Farach-Carson, M C; Wright, G C; Butler, W T

    1992-01-01

    A number of commercially available matrix filter supports have been designed for the immobilization of proteins following either electrotransfer from sodium dodecyl sulfate (SDS) polyacrylamide gels or direct application during dot blotting assays. These matrices differ with respect to chemical composition, charge, pore size, and degree of hydrophobicity. It follows that the properties of the protein(s) of interest will greatly influence the degree to which they interact with and ultimately bind to various filters. Acidic bone proteins contain diverse post-translational modifications that influence their interactions with solid phase matrices such as those used in immunoblotting (Western or dot blotting) or ion binding (overlay) procedures. This communication describes the results of a study comparing binding of various mixtures of non-collagenous acidic bone matrix phosphoproteins as well as purified osteopontin and osteocalcin to various filters including nitrocellulose and cationized paper or nylon. Based on our findings, we recommend the use of cationized filters for solid phase assays requiring the binding of these acidic macromolecules to background supports.

  10. Flagellar display of bone-protein-derived peptides for studying peptide-mediated biomineralization.

    PubMed

    Li, Dong; Newton, Salete M C; Klebba, Philip E; Mao, Chuanbin

    2012-11-27

    A bacterial flagellum is self-assembled primarily from thousands of flagellin (FliC), a protein subunit. A foreign peptide can be fully displayed on the surface of the flagellum through inserting it into every constituent protein subunit. To shed light on the role of bone proteins during the nucleation of hydroxyapatite (HAP), representative domains from type I collagen, including part of the N-,C-terminal, N-,C-zone around the hole zone and an eight repeat unit Gly-Pro-Pro (GPP8) sequence similar to the central sequence of type I collagen, were separately displayed on the surface of the flagella. Moreover, eight negatively charged, contiguous glutamic acid residues (E8) and two other characteristic sequences derived from a representative noncollagenous protein called bone sialoprotein (BSP) were also displayed on flagella. After being incubated in an HAP supersaturated precursor solution, flagella displaying E8 or GPP8 sequences were found to be coated with a layer of HAP nanocrystals. Very weak or no nucleation was observed on flagella displaying other peptides being tested. We also found that calcium ions can induce the assembly of the negatively charged E8 flagella into bundles mimicking collagen fibers, followed by the formation of HAP nanocrystals with the crystallographic c axis preferentially aligned with long axis of flagella, which is similar to that along the collagen fibrils in bone. This work demonstrates that because of the ease of the peptide display on flagella and the self-assembly of flagella, flagella can serve as a platform for studying biomineralization and as a building block to generate bonelike biomaterials.

  11. Selective protein depletion impairs bone growth and causes liver fatty infiltration in female rats: prevention by Spirulina alga.

    PubMed

    Fournier, C; Rizzoli, R; Bouzakri, K; Ammann, P

    2016-11-01

    Chronic protein malnutrition leads to child mortality in developing countries. Spirulina alga (Spi), being rich in protein and growing easily, is a good candidate as supplementation. We showed that Spi completely prevents bone growth retardation and liver disturbances observed in young rats fed a low protein diet. This supports Spi as a useful source of vegetable protein to fight against protein malnutrition. Chronic malnutrition is a main factor of child mortality in developing countries. A low protein diet impairs whole-body growth and leads to fatty liver in growing rats. Spi has great potential as a supplementation as it has a 60 % protein content and all essential amino acids. However, its specific impact on bone growth and the related secretion of hepatokines have not yet been studied. To address this question, 6-week-old female rats were fed isocaloric diets containing 10 % casein, 5 % casein, or 5 % casein + 5 % protein from Spi during 9 weeks. Changes in tibia geometry, microarchitecture, BMC, BMD, and biomechanical properties were analyzed. Serum IGF-I, FGF21, follistatin, and activin A were assessed as well as their hepatic gene expressions in addition to those of Sirt1, Ghr, and Igf1r. Hepatic fat content was also assessed. A low protein diet altered bone geometry and reduced proximal tibia BMD and trabecular bone volume. In addition, it increased hepatic fat content and led to hepatic GH resistance by decreasing serum IGF-I and increasing serum FGF21 without altering serum activin A and follistatin. Spi prevented low protein diet-induced bone, hepatic, and hormonal changes, and even led to higher biomechanical properties and lower hepatic fat content in association with specific InhbA and Follistatin expression changes vs. the 10 % casein group. Altogether our results demonstrate the preventive impact of Spi on bone growth delay and hepatic GH resistance in conditions of isocaloric dietary protein deficiency.

  12. Bovine-derived bone protein extract in the treatment of mandibular Class II furcations.

    PubMed

    Camargo, Paulo M; Wolinsky, Lawrence E; Burgess, Ann V; Wagner, William R; Paluk, S Fabian; Kenney, E Barrie

    2002-11-01

    This study was an initial evaluation of the use of a bovine-derived bone protein (BP) extract that contains various growth factors combined with decalcified freeze-dried bone allograft (DFDBA) as regenerative treatment for class II mandibular furcations. Tw