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Sample records for binds bmp2 bmp4

  1. Ectopic application of recombinant BMP-2 and BMP-4 can change patterning of developing chick facial primordia.

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    Barlow, A J; Francis-West, P H

    1997-01-01

    The facial primordia initially consist of buds of undifferentiated mesenchyme, which give rise to a variety of tissues including cartilage, muscle and nerve. These must be arranged in a precise spatial order for correct function. The signals that control facial outgrowth and patterning are largely unknown. The bone morphogenetic proteins Bmp-2 and Bmp-4 are expressed in discrete regions at the distal tips of the early facial primordia suggesting possible roles for BMP-2 and BMP-4 during chick facial development. We show that expression of Bmp-4 and Bmp-2 is correlated with the expression of Msx-1 and Msx-2 and that ectopic application of BMP-2 and BMP-4 can activate Msx-1 and Msx-2 gene expression in the developing facial primordia. We correlate this activation of gene expression with changes in skeletal development. For example, activation of Msx-1 gene expression across the distal tip of the mandibular primordium is associated with an extension of Fgf-4 expression in the epithelium and bifurcation of Meckel's cartilage. In the maxillary primordium, extension of the normal domain of Msx-1 gene expression is correlated with extended epithelial expression of shh and bifurcation of the palatine bone. We also show that application of BMP-2 can increase cell proliferation of the mandibular primordia. Our data suggest that BMP-2 and BMP-4 are part of a signalling cascade that controls outgrowth and patterning of the facial primordia.

  2. Expression of human bone morphogenetic protein (BMP-2 and BMP-4 genes in transgenic bovine fibroblasts Expressão dos genes bone morphogenetic protein (BMP-2 e BMP-4 em fibroblastos bovinos transgênicos

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    C. Oleskovicz

    2004-08-01

    Full Text Available cDNAs dos genes bone morphogenetic protein-2 (BMP-2 e bone morphogenetic protein-4 (BMP-4 foram sintetizados a partir de RNA total extraído de tecidos ósseos de pacientes que apresentavam trauma facial (fraturas do maxilar entre o 7º e o 10º dia pós-trauma e clonados num vetor para expressão em células mamíferas, sob controle do promotor de citomegalovírus (CMV. Os vetores contendo os genes BMP-2 e o BMP-4 foram utilizados para a transfecção de fibroblastos bovinos. mRNAs foram indiretamente detectados por RT-PCR nas células transfectadas. As proteínas BMP-2 e BMP-4 foram detectadas mediante análises de Western blot. Os resultados demonstram a possibilidade de produção desses fatores de crescimento celular em fibroblastos bovinos. Essas células poderão ser utilizadas como fontes doadoras de material genético para a técnica de transferência nuclear na geração de animais transgênicos.

  3. Regulation of Msx-1, Msx-2, Bmp-2 and Bmp-4 during foetal and postnatal mammary gland development.

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    Phippard, D J; Weber-Hall, S J; Sharpe, P T; Naylor, M S; Jayatalake, H; Maas, R; Woo, I; Roberts-Clark, D; Francis-West, P H; Liu, Y H; Maxson, R; Hill, R E; Dale, T C

    1996-09-01

    Expression of the Msx-1 and Msx-2 homeobox genes have been shown to be coordinately regulated with the Bmp-2 and Bmp-4 ligands in a variety of developing tissues. Here we report that transcripts from all four genes are developmentally regulated during both foetal and postnatal mammary gland development. The location and time-course of the Bmp and Msx expression point to a role for Msx and Bmp gene products in the control of epithelial-mesenchymal interactions. Expression of Msx-2, but not Msx-1, Bmp-2 or Bmp-4 was decreased following ovariectomy, while expression of the human Msx-2 homologue was regulated by 17beta-oestradiol in the MCF-7 breast cancer cell line. The regulation of Msx-2 expression by oestrogen raises the possibility that hormonal regulation of mammary development is mediated through the control of epithelial-mesenchymal interactions.

  4. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression.

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    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-05-05

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2(f/f);Bmp4(f/f)ameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling.

  5. Overlapping and differential localization of Bmp-2, Bmp-4, Msx-2 and apoptosis in the endocardial cushion and adjacent tissues of the developing mouse heart.

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    Abdelwahid, E; Rice, D; Pelliniemi, L J; Jokinen, E

    2001-07-01

    The bone morphogenetic proteins BMP-2 and BMP-4 and the homeobox gene MSX-2 are required for normal development of many embryonic tissues. To elucidate their possible roles during the remodeling of the tubular heart into a fully septated four-chambered heart, we have localized the mRNA of Bmp-2, Bmp-4, Msx-2 and apoptotic cells in the developing mouse heart from embryonic day (E)11 to E17. mRNA was localized by in situ hybridization, and apoptotic cells by TUNEL (TDT-mediated dUTP-biotin nick end-labeling) as well as by transmission electron microscopy. By analyzing adjacent serial sections, we demonstrated that the expression of Msx-2 and Bmp-2 strikingly overlapped in the atrioventricular canal myocardium, in the atrioventricular junctional myocardium, and in the maturing myocardium of the atrioventricular valves. Bmp-4 was expressed in the outflow tract myocardium and in the endocardial cushion of the outflow tract ridges from E12 to E14. Msx-2 appeared in the mesenchyme of the atrioventricular endocardial cushion from E11 to E14, while Bmp-2 and Bmp-4 were detected between E11 and E14. Apoptotic cells were also detected in the mesenchyme of the endocardial cushion between E12 and E14. Our results suggest that BMP-2 and MSX-2 are tightly linked to the formation of the atrioventricular junction and valves and that BMP-4 is involved in the development of the outflow tract myocardium and of the endocardial cushion. In addition, BMP-2, BMP-4 and MSX-2 and apoptosis seem to be associated with differentiation of the endocardial cushion.

  6. Multiple common susceptibility variants near BMP pathway loci GREM1, BMP4, and BMP2 explain part of the missing heritability of colorectal cancer.

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    Ian P M Tomlinson

    2011-06-01

    Full Text Available Genome-wide association studies (GWAS have identified 14 tagging single nucleotide polymorphisms (tagSNPs that are associated with the risk of colorectal cancer (CRC, and several of these tagSNPs are near bone morphogenetic protein (BMP pathway loci. The penalty of multiple testing implicit in GWAS increases the attraction of complementary approaches for disease gene discovery, including candidate gene- or pathway-based analyses. The strongest candidate loci for additional predisposition SNPs are arguably those already known both to have functional relevance and to be involved in disease risk. To investigate this proposition, we searched for novel CRC susceptibility variants close to the BMP pathway genes GREM1 (15q13.3, BMP4 (14q22.2, and BMP2 (20p12.3 using sample sets totalling 24,910 CRC cases and 26,275 controls. We identified new, independent CRC predisposition SNPs close to BMP4 (rs1957636, P = 3.93×10(-10 and BMP2 (rs4813802, P = 4.65×10(-11. Near GREM1, we found using fine-mapping that the previously-identified association between tagSNP rs4779584 and CRC actually resulted from two independent signals represented by rs16969681 (P = 5.33×10(-8 and rs11632715 (P = 2.30×10(-10. As low-penetrance predisposition variants become harder to identify-owing to small effect sizes and/or low risk allele frequencies-approaches based on informed candidate gene selection may become increasingly attractive. Our data emphasise that genetic fine-mapping studies can deconvolute associations that have arisen owing to independent correlation of a tagSNP with more than one functional SNP, thus explaining some of the apparently missing heritability of common diseases.

  7. Binding Interactions of Keratin-Based Hair Fiber Extract to Gold, Keratin, and BMP-2.

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    Roche C de Guzman

    Full Text Available Hair-derived keratin biomaterials composed mostly of reduced keratin proteins (kerateines have demonstrated their utility as carriers of biologics and drugs for tissue engineering. Electrostatic forces between negatively-charged keratins and biologic macromolecules allow for effective drug retention; attraction to positively-charged growth factors like bone morphogenetic protein 2 (BMP-2 has been used as a strategy for osteoinduction. In this study, the intermolecular surface and bulk interaction properties of kerateines were investigated. Thiol-rich kerateines were chemisorbed onto gold substrates to form an irreversible 2-nm rigid layer for surface plasmon resonance analysis. Kerateine-to-kerateine cohesion was observed in pH-neutral water with an equilibrium dissociation constant (KD of 1.8 × 10(-4 M, indicating that non-coulombic attractive forces (i.e. hydrophobic and van der Waals were at work. The association of BMP-2 to kerateine was found to be greater (KD = 1.1 × 10(-7 M, within the range of specific binding. Addition of salts (phosphate-buffered saline; PBS shortened the Debye length or the electrostatic field influence which weakened the kerateine-BMP-2 binding (KD = 3.2 × 10(-5 M. BMP-2 in bulk kerateine gels provided a limited release in PBS (~ 10% dissociation in 4 weeks, suggesting that electrostatic intermolecular attraction was significant to retain BMP-2 within the keratin matrix. Complete dissociation between kerateine and BMP-2 occurred when the PBS pH was lowered (to 4.5, below the keratin isoelectric point of 5.3. This phenomenon can be attributed to the protonation of keratin at a lower pH, leading to positive-positive repulsion. Therefore, the dynamics of kerateine-BMP-2 binding is highly dependent on pH and salt concentration, as well as on BMP-2 solubility at different pH and molarity. The study findings may contribute to our understanding of the release kinetics of drugs from keratin biomaterials and allow for the

  8. Immortalization and characterization of mouse floxed Bmp2/4 osteoblasts

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    Wu, Li-An; Yuan, Guohua; Yang, Guobin; Ortiz-Gonzalez, Iris; Yang, Wuchen; Cui, Yong; MacDougall, Mary; Donly, Kevin J.; Harris, Stephen; Chen, Shuo

    2009-01-01

    Generation of a floxed Bmp2/4 osteoblast cell line is a valuable tool for studying the modulatory effects of Bmp2 and Bmp4 on osteoblast differentiation as well as relevant molecular events. In this study, primary floxed Bmp2/4 mouse osteoblasts were cultured and transfected with simian virus 40 large T-antigen. Transfection was verified by polymerase chain reaction (PCR) and immunohistochemistry. To examine the characteristics of the transfected cells, morphology, proliferation and mineralization were analyzed, expression of cell-specific genes including Runx2, ATF4, Dlx3, Osx, dentin matrix protein 1, bone sialoprotein, osteopontin, osteocalcin, osteonectin and collagen type I was detected. These results show that transfected floxed Bmp2/4 osteoblasts bypassed senescence with a higher proliferation rate, but retain the genotypic and phenotypic characteristics similar to the primary cells. Thus, we for the first time demonstrate the establishment of an immortalized mouse floxed Bmp2/4 osteoblast cell line.

  9. Immortalization and characterization of mouse floxed Bmp2/4 osteoblasts

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    Wu, Li-An [Department of Pediatric Dentistry, The University of Texas Health Science Center at San Antonio, TX (United States); Department of Pediatric Dentistry, School of Stomatology, The Fourth Military Medical University, Xi-an (China); Yuan, Guohua; Yang, Guobin [Department of Pediatric Dentistry, The University of Texas Health Science Center at San Antonio, TX (United States); Key Laboratory of Oral Biomedical Engineering Ministry of Education, Wuhan (China); Ortiz-Gonzalez, Iris [Department of Pediatric Dentistry, The University of Texas Health Science Center at San Antonio, TX (United States); Yang, Wuchen; Cui, Yong [Department of Periodontics, Dental School, The University of Texas Health Science Center at San Antonio, TX (United States); MacDougall, Mary [Department of Oral/Maxillofacial Surgery, University of Alabama, Birmingham, AL (United States); Donly, Kevin J. [Department of Pediatric Dentistry, The University of Texas Health Science Center at San Antonio, TX (United States); Harris, Stephen [Department of Periodontics, Dental School, The University of Texas Health Science Center at San Antonio, TX (United States); Chen, Shuo, E-mail: chens0@uthscsa.edu [Department of Pediatric Dentistry, The University of Texas Health Science Center at San Antonio, TX (United States)

    2009-08-14

    Generation of a floxed Bmp2/4 osteoblast cell line is a valuable tool for studying the modulatory effects of Bmp2 and Bmp4 on osteoblast differentiation as well as relevant molecular events. In this study, primary floxed Bmp2/4 mouse osteoblasts were cultured and transfected with simian virus 40 large T-antigen. Transfection was verified by polymerase chain reaction (PCR) and immunohistochemistry. To examine the characteristics of the transfected cells, morphology, proliferation and mineralization were analyzed, expression of cell-specific genes including Runx2, ATF4, Dlx3, Osx, dentin matrix protein 1, bone sialoprotein, osteopontin, osteocalcin, osteonectin and collagen type I was detected. These results show that transfected floxed Bmp2/4 osteoblasts bypassed senescence with a higher proliferation rate, but retain the genotypic and phenotypic characteristics similar to the primary cells. Thus, we for the first time demonstrate the establishment of an immortalized mouse floxed Bmp2/4 osteoblast cell line.

  10. Risk variants in BMP4 promoters for nonsyndromic cleft lip/palate in a Chilean population

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    Suazo José

    2011-12-01

    Full Text Available Abstract Background Bone morphogenetic protein 4 gene (BMP4 plays a key role during maxillofacial development, since orofacial clefts are observed in animals when this gene is conditionally inactivated. We recently reported the existence of association between nonsyndromic cleft lip/palate (NSCLP and BMP4 polymorphisms by detecting transmission deviations for haplotypes that include a region containing a BMP4 promoter in case-parent trios. The aim of the present study was to search for possible causal mutations within BMP4 promoters (BMP4.1 and BMP4.2. Methods We analyzed the sequence of BMP4.1 and BMP4.2 in 167 Chilean NSCLP cases and 336 controls. Results We detected three novel variants in BMP4.1 (c.-5514G > A, c.-5365C > T and c.-5049C > T which could be considered as cleft risk factors due to their absence in controls. Additionally, rs2855530 G allele (BMP4.2 carriers showed an increased risk for NSCLP restricted to males (OR = 1.52; 95% C.I. = 1.07-2.15; p = 0.019. For this same SNP the dominant genotype model showed a higher frequency of G/G+G/C and a lower frequency of C/C in cases than controls in the total sample (p = 0.03 and in the male sample (p = 0.003. Bioinformatic prediction analysis showed that all the risk variants detected in this study could create new transcription factor binding motifs. Conclusions The sex-dependent association between rs2855530 and NSCLP could indirectly be related to the differential gene expression observed between sexes in animal models. We concluded that risk variants detected herein could potentially alter BMP4 promoter activity in NSCLP. Further functional and developmental studies are necessary to support this hypothesis.

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

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

    2018-02-01

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

  12. BMP4 density gradient in disk-shaped confinement

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    Bozorgui, Behnaz; Teimouri, Hamid; Kolomeisky, Anatoly B.

    We present a quantitative model that explains the scaling of BMP4 gradients during gastrulation and the recent experimental observation that geometric confinement of human embryonic stem cells is sufficient to recapitulate much of germ layer patterning. Based on a assumption that BMP4 diffusion rate is much smaller than the diffusion rate of it's inhibitor molecules, our results confirm that the length-scale which defines germ layer territories does not depend on system size.

  13. Perlecan domain 1 recombinant proteoglycan augments BMP-2 activity and osteogenesis

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    DeCarlo Arthur A

    2012-09-01

    Full Text Available Abstract Background Many growth factors, such as bone morphogenetic protein (BMP-2, have been shown to interact with polymers of sulfated disacharrides known as heparan sulfate (HS glycosaminoglycans (GAGs, which are found on matrix and cell-surface proteoglycans throughout the body. HS GAGs, and some more highly sulfated forms of chondroitin sulfate (CS, regulate cell function by serving as co-factors, or co-receptors, in GF interactions with their receptors, and HS or CS GAGs have been shown to be necessary for inducing signaling and GF activity, even in the osteogenic lineage. Unlike recombinant proteins, however, HS and CS GAGs are quite heterogenous due, in large part, to post-translational addition, then removal, of sulfate groups to various positions along the GAG polymer. We have, therefore, investigated whether it would be feasible to deliver a DNA pro-drug to generate a soluble HS/CS proteoglycan in situ that would augment the activity of growth-factors, including BMP-2, in vivo. Results Utilizing a purified recombinant human perlecan domain 1 (rhPln.D1 expressed from HEK 293 cells with HS and CS GAGs, tight binding and dose-enhancement of rhBMP-2 activity was demonstrated in vitro. In vitro, the expressed rhPln.D1 was characterized by modification with sulfated HS and CS GAGs. Dose-enhancement of rhBMP-2 by a pln.D1 expression plasmid delivered together as a lyophilized single-phase on a particulate tricalcium phosphate scaffold for 6 or more weeks generated up to 9 fold more bone volume de novo on the maxillary ridge in a rat model than in control sites without the pln.D1 plasmid. Using a significantly lower BMP-2 dose, this combination provided more than 5 times as much maxillary ridge augmentation and greater density than rhBMP-2 delivered on a collagen sponge (InFuse™. Conclusions A recombinant HS/CS PG interacted strongly and functionally with BMP-2 in binding and cell-based assays, and, in vivo, the pln.247 expression plasmid

  14. Asymmetric BMP4 signalling improves the realism of kidney organoids.

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    Mills, Christopher G; Lawrence, Melanie L; Munro, David A D; Elhendawi, Mona; Mullins, John J; Davies, Jamie A

    2017-11-01

    We present a strategy for increasing the anatomical realism of organoids by applying asymmetric cues to mimic spatial information that is present in natural embryonic development, and demonstrate it using mouse kidney organoids. Existing methods for making kidney organoids in mice yield developing nephrons arranged around a symmetrical collecting duct tree that has no ureter. We use transplant experiments to demonstrate plasticity in the fate choice between collecting duct and ureter, and show that an environment rich in BMP4 promotes differentiation of early collecting ducts into uroplakin-positive, unbranched, ureter-like epithelial tubules. Further, we show that application of BMP4-releasing beads in one place in an organoid can break the symmetry of the system, causing a nearby collecting duct to develop into a uroplakin-positive, broad, unbranched, ureter-like 'trunk' from one end of which true collecting duct branches radiate and induce nephron development in an arrangement similar to natural kidneys. The idea of using local symmetry-breaking cues to improve the realism of organoids may have applications to organoid systems other than the kidney.

  15. Plasma Treated High-Density Polyethylene (HDPE Medpor Implant Immobilized with rhBMP-2 for Improving the Bone Regeneration

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    Jin-Su Lim

    2014-01-01

    Full Text Available We investigate the bone generation capacity of recombinant human bone morphogenetic protein-2 (rhBMP-2 immobilized Medpor surface through acrylic acid plasma-polymerization. Plasma-polymerization was carried out at a 20 W at an acrylic acid flow rate of 7 sccm for 5 min. The plasma-polymerized Medpor surface showed hydrophilic properties and possessed a high density of carboxyl groups. The rhBMP-2 was immobilized with covalently attached carboxyl groups using 1-ethyl-3-(3-dimethylaminopropyl carbodiimide and N-hydroxysuccinimide. Carboxyl groups and rhBMP-2 immobilization on the Medpor surface were identified by Fourier transform infrared spectroscopy. The activity of Medpor with rhBMP-2 immobilized was examined using an alkaline phosphatase assay on MC3T3-E1 cultured Medpor. These results showed that the rhBMP-2 immobilized Medpor increased the level of MC3T3-E1 cell differentiation. These results demonstrated that plasma surface modification has the potential to immobilize rhBMP-2 on polymer implant such as Medpor and can be used for the binding of bioactive nanomolecules in bone tissue engineering.

  16. Cathepsin H indirectly regulates morphogenetic protein-4 (BMP-4) in various human cell lines

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    Rojnik, Matija; Jevnikar, Zala; Mirkovic, Bojana; Janes, Damjan; Zidar, Nace; Kikelj, Danijel; Kos, Janko

    2011-01-01

    Background Cathepsin H is a cysteine protease considered to play a major role in tumor progression, however, its precise function in tumorigenesis is unclear. Cathepsin H was recently proposed to be involved in processing of bone morphogenetic protein 4 (BMP-4) in mice. In order to clarify whether cathepsin H also regulates BMP-4 in humans, its impact on BMP-4 expression, processing and degradation was investigated in prostate cancer (PC-3), osteosarcoma (HOS) and pro-monocytic (U937) human cell lines. Materials and methods BMP-4 expression was founded to be regulated by cathepsin H using PCR array technology and confirmed by real time PCR. Immunoassays including Western blot and confocal microscopy were used to evaluate the influence of cathepsin H on BMP-4 processing. Results In contrast to HOS, the expression of BMP-4 mRNA in U937 and PC3 cells was significantly decreased by cathepsin H. The different regulation of BMP-4 synthesis could be associated with the absence of the mature 28 kDa cathepsin H form in HOS cells, where only the intermediate 30 kDa form was observed. No co-localization of BMP-4 and cathepsin H was observed in human cell lines and the multistep processing of BMP-4 was not altered in the presence of specific cathepsin H inhibitor. Isolated cathepsin H does not cleave mature recombinant BMP-4, neither with its amino- nor its endopeptidase activity. Conclusions Our results exclude direct proteolytic processing of BMP-4 by cathepsin H, however, they provide support for its involvement in the regulation of BMP-4 expression. PMID:22933963

  17. 2-N, 6-O-sulfated chitosan-assisted BMP-2 immobilization of PCL scaffolds for enhanced osteoinduction

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    Cao, Lingyan [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); CSIRO Manufacturing, Bayview Avenue, Clayton, Victoria 3168 (Australia); Department of Prosthodontics, College of Stomatology, Ninth People' s Hospital, School of Medicine, Shanghai Jiao Tong University, 639 Zhizaoju Road, Shanghai 200011 (China); Yu, Yuanman [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Wang, Jing, E-mail: biomatwj@163.com [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Werkmeister, Jerome A [CSIRO Manufacturing, Bayview Avenue, Clayton, Victoria 3168 (Australia); McLean, Keith M, E-mail: Keith.McLean@csiro.au [CSIRO Manufacturing, Bayview Avenue, Clayton, Victoria 3168 (Australia); Liu, Changsheng, E-mail: liucs@ecust.edu.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Engineering Research Center for Biomedical Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China)

    2017-05-01

    The aim of this study was to develop a 2-N, 6-O-sulfated chitosan (26SCS) modified electrospun fibrous PCL scaffold for bone morphogenetic protein-2 (BMP-2) delivery to improve osteoinduction. The PCL scaffold was modified by an aminolysis reaction using ethylenediamine (ED) and 26SCS was immobilized via electrostatic interactions (PCL-N-S). Scaffolds were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and contact angle measurements. In vitro BMP-2 adsorption and release kinetics indicated that modified PCL-N-S scaffolds showed higher levels of binding of BMP-2 (about 30–100 times), moderative burst release (about one third), and prolonged releasing time compared to the unmodified PCL scaffold. The bioactivity of released BMP-2 determined by alkaline phosphatase (ALP) activity assay was maintained and improved 8– 12 times with increasing concentration of immobilized 26SCS on the scaffolds. In vitro studies demonstrated that bone marrow mesenchymal stem cells (BMSCs) attached more readily to the PCL-N-S scaffolds with increased spreading. In conclusion, 26SCS modified PCL scaffolds can be a potent system for the sustained and bioactive delivery of BMP-2. - Graphical abstract: Limited self-regenerating capacity of human body makes the reconstruction of critical size bone defect a significant challenge. Although bone morphogenetic protein-2 (BMP-2) is an important differentiation factor inducing bone regeneration, it's short half-life in vivo and potent side effect at high dosage still show lots of concerns in the clinical use. Herein, modification of electrospun PCL scaffolds was presented through immobilizing of sulfated chitosan (26SCS). The modified scaffolds effectively improve the binding capacity of BMP-2 and exhibited an enhanced bioactivity and sustained release in vitro. Thus, the use of 26SCS modified PCL scaffolds combined with BMP-2 could be a useful scaffold for tissue

  18. Production of BMP4 by endothelial cells is crucial for endogenous thymic regeneration

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    Wertheimer, Tobias; Velardi, Enrico; Tsai, Jennifer; Cooper, Kirsten; Xiao, Shiyun; Kloss, Christopher C.; Ottmüller, Katja J.; Mokhtari, Zeinab; Brede, Christian; deRoos, Paul; Kinsella, Sinéad; Palikuqi, Brisa; Ginsberg, Michael; Young, Lauren F.; Kreines, Fabiana; Lieberman, Sophia R.; Lazrak, Amina; Guo, Peipei; Malard, Florent; Smith, Odette M.; Shono, Yusuke; Jenq, Robert R.; Hanash, Alan M.; Nolan, Daniel J.; Butler, Jason M.; Beilhack, Andreas; Manley, Nancy R.; Rafii, Shahin; Dudakov, Jarrod A; van den Brink, Marcel RM

    2018-01-01

    The thymus is extremely sensitive to damage but also has a remarkable ability to repair itself. However, the mechanisms underlying this endogenous regeneration remain poorly understood and this capacity diminishes considerably with age. Here we show that thymic endothelial cells (ECs) comprise a critical pathway of regeneration, via their production of BMP4. ECs increased their production of BMP4 after thymic damage, and abrogating BMP4 signalling or production by either pharmacologic or genetic inhibition impaired thymic repair. EC-derived BMP4 acted on thymic epithelial cells (TECs) to increase their expression of Foxn1, a key transcription factor involved in TEC development, maintenance and regeneration; and its downstream targets such as Dll4, itself a key mediator of thymocyte development and regeneration. These studies demonstrate the importance of the BMP4 pathway in endogenous tissue regeneration and offer a potential clinical approach to enhance T cell immunity. PMID:29330161

  19. Secreted phosphoprotein 24 kD (Spp24) inhibits growth of human pancreatic cancer cells caused by BMP-2

    International Nuclear Information System (INIS)

    Li, Chen-Shuang; Tian, Haijun; Zou, Min; Zhao, Ke-Wei; Li, Yawei; Lao, Lifeng; Brochmann, Elsa J.; Duarte, M. Eugenia L.; Daubs, Michael D.; Zhou, Yan-Heng; Murray, Samuel S.; Wang, Jeffrey C.

    2015-01-01

    The emerging role of bone morphogenetic proteins (BMPs) in the initiation and progression of multiple cancers has drawn great attention in cancer research. In this study, we report that BMP-2 can promote the proliferation of the pancreatic tumor cell line, PANC-1. Secreted phosphoprotein 24 kD (Spp24), a BMP binding protein, did not affect the proliferation of the cells but promoted the apoptosis of the cells in vitro. In a xeneograft tumor model using PANC-1 cells, BMP-2 dramatically promoted tumor growth, while Spp24 not only abolished the effect of BMP-2, but also dramatically induced tumor shrinking when used alone. Activation of Smad1/5/8 participated in this process as demonstrated by immunohistochemical staining of phosphorylated Smad 1/5/8. We conclude that Spp24 can be developed into a therapeutic agent that could be employed in clinical situations where the inhibition of BMPs and related proteins is advantageous. - Highlights: • Spp24 effectively inhibited the in vivo tumor growth of PANC-1. • BMP-2 dramatically promoted tumor growth by promoting PANC-1 proliferation. • Spp24 abolished the tumor growth effect of BMP-2 by promoting PANC-1 apoptosis. • Spp24 may be a candidate as a therapeutic agent of pancreatic cancer.

  20. Secreted phosphoprotein 24 kD (Spp24) inhibits growth of human pancreatic cancer cells caused by BMP-2

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    Li, Chen-Shuang [Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing (China); Tian, Haijun, E-mail: haijuntianmd@gmail.com [Department of Orthopaedic Surgery, Changzheng Hospital, Second Military Medical University, Shanghai (China); Department of Orthopaedic Surgery, University of California, Los Angeles, Los Angeles, CA (United States); Department of Surgery, Bethune School of Medics, Shijiazhuang (China); Zou, Min [Department of Orthodontics, School and Hospital of Stomatology, Xi' an Jiaotong University, Xi' an (China); Zhao, Ke-Wei [Research Service, VA Greater Los Angeles Healthcare System, North Hills, CA (United States); Li, Yawei; Lao, Lifeng [Department of Orthopaedic Surgery, University of California, Los Angeles, Los Angeles, CA (United States); Brochmann, Elsa J. [Research Service, VA Greater Los Angeles Healthcare System, North Hills, CA (United States); Geriatric Research, Education and Clinical Center, VA Greater Los Angeles Healthcare System, North Hills, CA (United States); Department of Medicine, University of California, Los Angeles, Los Angeles, CA (United States); Duarte, M. Eugenia L. [National Institute of Traumatology and Orthopaedics, Rio de Janeiro (Brazil); Daubs, Michael D. [Division of Orthopaedic Surgery, Department of Surgery, University of Nevada School of Medicine, Las Vegas, NV (United States); Zhou, Yan-Heng, E-mail: yanhengzhou@vip.163.com [Department of Orthodontics, Peking University School and Hospital of Stomatology, Beijing (China); Murray, Samuel S. [Research Service, VA Greater Los Angeles Healthcare System, North Hills, CA (United States); Geriatric Research, Education and Clinical Center, VA Greater Los Angeles Healthcare System, North Hills, CA (United States); Department of Medicine, University of California, Los Angeles, Los Angeles, CA (United States); Wang, Jeffrey C. [Department of Orthopaedic Surgery, University of Southern California, Los Angeles, CA (United States)

    2015-10-16

    The emerging role of bone morphogenetic proteins (BMPs) in the initiation and progression of multiple cancers has drawn great attention in cancer research. In this study, we report that BMP-2 can promote the proliferation of the pancreatic tumor cell line, PANC-1. Secreted phosphoprotein 24 kD (Spp24), a BMP binding protein, did not affect the proliferation of the cells but promoted the apoptosis of the cells in vitro. In a xeneograft tumor model using PANC-1 cells, BMP-2 dramatically promoted tumor growth, while Spp24 not only abolished the effect of BMP-2, but also dramatically induced tumor shrinking when used alone. Activation of Smad1/5/8 participated in this process as demonstrated by immunohistochemical staining of phosphorylated Smad 1/5/8. We conclude that Spp24 can be developed into a therapeutic agent that could be employed in clinical situations where the inhibition of BMPs and related proteins is advantageous. - Highlights: • Spp24 effectively inhibited the in vivo tumor growth of PANC-1. • BMP-2 dramatically promoted tumor growth by promoting PANC-1 proliferation. • Spp24 abolished the tumor growth effect of BMP-2 by promoting PANC-1 apoptosis. • Spp24 may be a candidate as a therapeutic agent of pancreatic cancer.

  1. Interactions between Bmp-4 and Msx-1 act to restrict gene expression to odontogenic mesenchyme.

    Science.gov (United States)

    Tucker, A S; Al Khamis, A; Sharpe, P T

    1998-08-01

    Tooth development is regulated by a reciprocal series of epithelial-mesenchymal interactions. Bmp4 has been identified as a candidate signalling molecule in these interactions, initially as an epithelial signal and then later at the bud stage as a mesenchymal signal (Vainio et al. [1993] Cell 75:45-58). A target gene for Bmp4 signalling is the homeobox gene Msx-1, identified by the ability of recombinant Bmp4 protein to induce expression in mesenchyme. There is, however, no evidence that Bmp4 is the endogenous inducer of Msx-1 expression. Msx-1 and Bmp-4 show dynamic, interactive patterns of expression in oral epithelium and ectomesenchyme during the early stages of tooth development. In this study, we compare the temporal and spatial expression of these two genes to determine whether the changing expression patterns of these genes are consistent with interactions between the two molecules. We show that changes in Bmp-4 expression precede changes in Msx-1 expression. At embryonic day (E)10.5-E11.0, expression patterns are consistent with BMP4 from the epithelium, inducing or maintaining Msx-1 in underlying mesenchyme. At E11.5, Bmp-4 expression shifts from epithelium to mesenchyme and is rapidly followed by localised up-regulation of Msx-1 expression at the sites of Bmp-4 expression. Using cultured explants of developing mandibles, we confirm that exogenous BMP4 is capable of replacing the endogenous source in epithelium and inducing Msx-1 gene expression in mesenchyme. By using noggin, a BMP inhibitor, we show that endogenous Msx-1 expression can be inhibited at E10.5 and E11.5, providing the first evidence that endogenous Bmp-4 from the epithelium is responsible for regulating the early spatial expression of Msx-1. We also show that the mesenchymal shift in Bmp-4 is responsible for up-regulating Msx-1 specifically at the sites of future tooth formation. Thus, we establish that a reciprocal series of interactions act to restrict expression of both genes to future

  2. Comparison of newly developed anti-bone morphogenetic protein 4 llama-derived antibodies with commercially available BMP4 inhibitors.

    Science.gov (United States)

    Calpe, Silvia; Correia, Ana C P; Sancho-Serra, Maria Del Carmen; Krishnadath, Kausilia K

    2016-01-01

    Due to improved understanding of the role of bone morphogenetic protein 4 (BMP4) in an increasing number of diseases, the development of selective inhibitors of BMP4 is an attractive therapeutic option. The currently available BMP4 inhibitors are not suitable as therapeutics because of their low specificity and low effectiveness. Here, we compared newly generated anti-BMP4 llama-derived antibodies (VHHs) with 3 different types of commercially available BMP4 inhibitors, natural antagonists, small molecule BMPR inhibitors and conventional anti-BMP4 monoclonal antibodies. We found that the anti-BMP4 VHHs were as effective as the natural antagonist or small molecule inhibitors, but had higher specificity. We also showed that commercial anti-BMP4 antibodies were inferior in terms of both specificity and effectiveness. These findings might result from the fact that the VHHs C4C4 and C8C8 target a small region within the BMPR1 epitope of BMP4, whereas the commercial antibodies target other areas of the BMP4 molecule. Our results show that the newly developed anti-BMP4 VHHs are promising antibodies with better specificity and effectivity for inhibition of BMP4, making them an attractive tool for research and for therapeutic applications.

  3. Role of ID Proteins in BMP4 Inhibition of Profibrotic Effects of TGF-β2 in Human TM Cells.

    Science.gov (United States)

    Mody, Avani A; Wordinger, Robert J; Clark, Abbot F

    2017-02-01

    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. 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. 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 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 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.

  4. BMP4 signaling is involved in the generation of inner ear sensory epithelia

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    Wang Yucheng

    2005-08-01

    Full Text Available Abstract Background The robust expression of BMP4 in the incipient sensory organs of the inner ear suggests possible roles for this signaling protein during induction and development of auditory and vestibular sensory epithelia. Homozygous BMP4-/- animals die before the inner ear's sensory organs develop, which precludes determining the role of BMP4 in these organs with simple gene knockout experiments. Results Here we use a chicken otocyst culture system to perform quantitative studies on the development of inner ear cell types and show that hair cell and supporting cell generation is remarkably reduced when BMP signaling is blocked, either with its antagonist noggin or by using soluble BMP receptors. Conversely, we observed an increase in the number of hair cells when cultured otocysts were treated with exogenous BMP4. BMP4 treatment additionally prompted down-regulation of Pax-2 protein in proliferating sensory epithelial progenitors, leading to reduced progenitor cell proliferation. Conclusion Our results implicate BMP4 in two events during chicken inner ear sensory epithelium formation: first, in inducing the switch from proliferative sensory epithelium progenitors to differentiating epithelial cells and secondly, in promoting the differentiation of hair cells within the developing sensory epithelia.

  5. Calcium phosphate implants coatings as carriers for BMP-2

    NARCIS (Netherlands)

    Liu, Y.; He, J.F.; Hunziker, E.B.

    2009-01-01

    The osteoconductivity of dental implants can be improved by coating them with a layer of calcium phosphate (CaP), which can be rendered osteoinductive by functionalizing it with an osteogenic agent, such as bone morphogenetic protein 2 (BMP-2). In the present study, we wished to compare the

  6. 3D bioprinting of BMSC-laden methacrylamide gelatin scaffolds with CBD-BMP2-collagen microfibers.

    Science.gov (United States)

    Du, Mingchun; Chen, Bing; Meng, Qingyuan; Liu, Sumei; Zheng, Xiongfei; Zhang, Cheng; Wang, Heran; Li, Hongyi; Wang, Nuo; Dai, Jianwu

    2015-12-18

    Three-dimensional (3D) bioprinting combines biomaterials, cells and functional components into complex living tissues. Herein, we assembled function-control modules into cell-laden scaffolds using 3D bioprinting. A customized 3D printer was able to tune the microstructure of printed bone mesenchymal stem cell (BMSC)-laden methacrylamide gelatin scaffolds at the micrometer scale. For example, the pore size was adjusted to 282 ± 32 μm and 363 ± 60 μm. To match the requirements of the printing nozzle, collagen microfibers with a length of 22 ± 13 μm were prepared with a high-speed crusher. Collagen microfibers bound bone morphogenetic protein 2 (BMP2) with a collagen binding domain (CBD) as differentiation-control module, from which BMP2 was able to be controllably released. The differentiation behaviors of BMSCs in the printed scaffolds were compared in three microenvironments: samples without CBD-BMP2-collagen microfibers in the growth medium, samples without microfibers in the osteogenic medium and samples with microfibers in the growth medium. The results indicated that BMSCs showed high cell viability (>90%) during printing; CBD-BMP2-collagen microfibers induced BMSC differentiation into osteocytes within 14 days more efficiently than the osteogenic medium. Our studies suggest that these function-control modules are attractive biomaterials and have potential applications in 3D bioprinting.

  7. Differential expression of a BMP4 reporter allele in anterior fungiform versus posterior circumvallate taste buds of mice

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    Barlow Linda A

    2010-10-01

    Full Text Available Abstract Background Bone Morphogenetic Protein 4 (BMP4 is a diffusible factor which regulates embryonic taste organ development. However, the role of BMP4 in taste buds of adult mice is unknown. We utilized transgenic mice with LacZ under the control of the BMP4 promoter to reveal the expression of BMP4 in the tongues of adult mice. Further we evaluate the pattern of BMP4 expression with that of markers of specific taste bud cell types and cell proliferation to define and compare the cell populations expressing BMP4 in anterior (fungiform papillae and posterior (circumvallate papilla tongue. Results BMP4 is expressed in adult fungiform and circumvallate papillae, i.e., lingual structures composed of non-taste epithelium and taste buds. Unexpectedly, we find both differences and similarities with respect to expression of BMP4-driven ß-galactosidase. In circumvallate papillae, many fusiform cells within taste buds are BMP4-ß-gal positive. Further, a low percentage of BMP4-expressing cells within circumvallate taste buds is immunopositive for markers of each of the three differentiated taste cell types (I, II and III. BMP4-positive intragemmal cells also expressed a putative marker of immature taste cells, Sox2, and consistent with this finding, intragemmal cells expressed BMP4-ß-gal within 24 hours after their final mitosis, as determined by BrdU birthdating. By contrast, in fungiform papillae, BMP4-ß-gal positive cells are never encountered within taste buds. However, in both circumvallate and fungiform papillae, BMP4-ß-gal expressing cells are located in the perigemmal region, comprising basal and edge epithelial cells adjacent to taste buds proper. This region houses the proliferative cell population that gives rise to adult taste cells. However, perigemmal BMP4-ß-gal cells appear mitotically silent in both fungiform and circumvallate taste papillae, as we do not find evidence of their active proliferation using cell cycle immunomarkers

  8. Differential expression of a BMP4 reporter allele in anterior fungiform versus posterior circumvallate taste buds of mice.

    Science.gov (United States)

    Nguyen, Ha M; Barlow, Linda A

    2010-10-13

    Bone Morphogenetic Protein 4 (BMP4) is a diffusible factor which regulates embryonic taste organ development. However, the role of BMP4 in taste buds of adult mice is unknown. We utilized transgenic mice with LacZ under the control of the BMP4 promoter to reveal the expression of BMP4 in the tongues of adult mice. Further we evaluate the pattern of BMP4 expression with that of markers of specific taste bud cell types and cell proliferation to define and compare the cell populations expressing BMP4 in anterior (fungiform papillae) and posterior (circumvallate papilla) tongue. BMP4 is expressed in adult fungiform and circumvallate papillae, i.e., lingual structures composed of non-taste epithelium and taste buds. Unexpectedly, we find both differences and similarities with respect to expression of BMP4-driven ß-galactosidase. In circumvallate papillae, many fusiform cells within taste buds are BMP4-ß-gal positive. Further, a low percentage of BMP4-expressing cells within circumvallate taste buds is immunopositive for markers of each of the three differentiated taste cell types (I, II and III). BMP4-positive intragemmal cells also expressed a putative marker of immature taste cells, Sox2, and consistent with this finding, intragemmal cells expressed BMP4-ß-gal within 24 hours after their final mitosis, as determined by BrdU birthdating. By contrast, in fungiform papillae, BMP4-ß-gal positive cells are never encountered within taste buds. However, in both circumvallate and fungiform papillae, BMP4-ß-gal expressing cells are located in the perigemmal region, comprising basal and edge epithelial cells adjacent to taste buds proper. This region houses the proliferative cell population that gives rise to adult taste cells. However, perigemmal BMP4-ß-gal cells appear mitotically silent in both fungiform and circumvallate taste papillae, as we do not find evidence of their active proliferation using cell cycle immunomarkers and BrdU birthdating. Our data suggest that

  9. Nestin-positive mesenchymal stem cells favour the astroglial lineage in neural progenitors and stem cells by releasing active BMP4

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    Leprince Pierre

    2004-09-01

    Full Text Available Abstract Background Spontaneous repair is limited after CNS injury or degeneration because neurogenesis and axonal regrowth rarely occur in the adult brain. As a result, cell transplantation has raised much interest as potential treatment for patients with CNS lesions. Several types of cells have been considered as candidates for such cell transplantation and replacement therapies. Foetal brain tissue has already been shown to have significant effects in patients with Parkinson's disease. Clinical use of the foetal brain tissue is, however, limited by ethical and technical problems as it requires high numbers of grafted foetal cells and immunosuppression. Alternatively, several reports suggested that mesenchymal stem cells, isolated from adult bone marrow, are multipotent cells and could be used in autograft approach for replacement therapies. Results In this study, we addressed the question of the possible influence of mesenchymal stem cells on neural stem cell fate. We have previously reported that adult rat mesenchymal stem cells are able to express nestin in defined culture conditions (in the absence of serum and after 25 cell population doublings and we report here that nestin-positive (but not nestin-negative mesenchymal stem cells are able to favour the astroglial lineage in neural progenitors and stem cells cultivated from embryonic striatum. The increase of the number of GFAP-positive cells is associated with a significant decrease of the number of Tuj1- and O4-positive cells. Using quantitative RT-PCR, we demonstrate that mesenchymal stem cells express LIF, CNTF, BMP2 and BMP4 mRNAs, four cytokines known to play a role in astroglial fate decision. In this model, BMP4 is responsible for the astroglial stimulation and oligodendroglial inhibition, as 1 this cytokine is present in a biologically-active form only in nestin-positive mesenchymal stem cells conditioned medium and 2 anti-BMP4 antibodies inhibit the nestin-positive mesenchymal

  10. The cholinergic-inducing effect of BMP4 on rat's cerebral neural stem cells

    International Nuclear Information System (INIS)

    Chang Yan; Xue Yilong; Luo Yun; Tian Lei; Pan Jingkun; Cui Xin

    2004-01-01

    The cholinergic-inducing effect of BMP4 on isolated and cultivated rat's cerebral neural stem cells (NSC) was examined. NSC isolated from two months old rat's brain region like hippocampus and striatum was cultivated in a DMEM/F12 medium containing EGF and bFGF, and was identified with morphological character and nestin immunocytochemistry test. After 24 hours, cultivating the NSC with the BMP4-added medium for 7-8 days, then the microscopical change were observed, ChAT and nestin double-labelling immunocytochemistry test was done. Results showed that about 34% NSC of neuron-like character was observed by microscope in the paper. That ChAT-positive cells coexist with nestin-positive cells was found by immunocytochemistry test. There were 28% ChAT-positive cells and 38% nestin-positive cells in the study. Cholinergic neurons differentiated from NSC could be induced by adding BMP4 to the medium

  11. Haploinsufficient Bmp4 ocular phenotypes include anterior segment dysgenesis with elevated intraocular pressure

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    Nusinowitz Steven

    2001-11-01

    Full Text Available Abstract Background Glaucoma is a blinding disease usually associated with high intraocular pressure (IOP. In some families, abnormal anterior segment development contributes to glaucoma. The genes causing anterior segment dysgenesis and glaucoma in most of these families are not identified and the affected developmental processes are poorly understood. Bone morphogenetic proteins (BMPs participate in various developmental processes. We tested the importance of Bmp4 gene dosage for ocular development and developmental glaucoma. Results Bmp4+/- mice have anterior segment abnormalities including malformed, absent or blocked trabecular meshwork and Schlemm's canal drainage structures. Mice with severe drainage structure abnormalities, over 80% or more of their angle's extent, have elevated IOP. The penetrance and severity of abnormalities is strongly influenced by genetic background, being most severe on the C57BL/6J background and absent on some other backgrounds. On the C57BL/6J background there is also persistence of the hyaloid vasculature, diminished numbers of inner retinal cells, and absence of the optic nerve. Conclusions We demonstrate that heterozygous deficiency of BMP4 results in anterior segment dysgenesis and elevated IOP. The abnormalities are similar to those in human patients with developmental glaucoma. Thus, BMP4 is a strong candidate to contribute to Axenfeld-Rieger anomaly and other developmental conditions associated with human glaucoma. BMP4 also participates in posterior segment development and wild-type levels are usually critical for optic nerve development on the C57BL/6J background. Bmp4+/- mice are useful for studying various components of ocular development, and may allow identification of strain specific modifiers affecting a variety of ocular phenotypes.

  12. Matrix-immobilized BMP-2 on microcontact printed fibronectin as in vitro tool to study BMP-mediated signaling and cell migration

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    Kristin eHauff

    2015-05-01

    Full Text Available During development, bone morphogenetic proteins (BMPs exert important functions in several tissues by regulating signaling for cell differentiation and migration. In vivo the extracellular matrix (ECM not only provides a support for adherent cells, but also presents a reservoir of growth factors (GFs. Several constituents of the ECM provide adhesive cues, which serve as binding sites for cell transmembrane receptors, such as integrins, which convey adhesion-mediated signaling to the intracellular compartment. Integrins do not function alone but rather crosstalk and cooperate with other receptors, such as GF receptors, in regulating cell responses to extracellular signals. To this, we present here the immobilization of BMP-2 onto cellular fibronectin (cFN, a key protein of the ECM, to investigate their impact on GF-mediated signaling and migration.Following biotinylation, BMP-2 was linked to biotinylated cFN using NeutrAvidin (NA as cross-linker. Characterization with QCM-D and ELISA confirmed the efficient immobilization of BMP-2 on cFN over a period of 24 h.To validate the bioactivity of matrix-immobilized BMP-2 (iBMP-2 we investigated short- and long-term responses of C2C12 myoblasts in comparison to soluble BMP-2 (sBMP-2 or in absence of GFs. Similarly to sBMP-2, iBMP-2 triggered Smad 1/5 phosphorylation and translocation into the nucleus corresponding to the activation of BMP-mediated Smad-dependent pathway. Additionally, successful suppression of myotube formation was observed after six days.We next implemented this approach to fabricate cFN micro patterned stripes by soft lithography. These stripes only allowed cell-surface interaction on the pattern due to passivation of the surface in between, thus serving as platform for studies on directed cell migration. During a 10 h-period, cells showed an increased migratory activity upon BMP-2 exposure.Thus, this versatile tool retains the GF's bioactivity and allows the presentation of ECM

  13. Functional cardiomyocytes derived from Isl1 cardiac progenitors via Bmp4 stimulation.

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    Esra Cagavi

    Full Text Available As heart failure due to myocardial infarction remains a leading cause of morbidity worldwide, cell-based cardiac regenerative therapy using cardiac progenitor cells (CPCs could provide a potential treatment for the repair of injured myocardium. As adult CPCs may have limitations regarding tissue accessibility and proliferative ability, CPCs derived from embryonic stem cells (ESCs could serve as an unlimited source of cells with high proliferative ability. As one of the CPCs that can be derived from embryonic stem cells, Isl1 expressing cardiac progenitor cells (Isl1-CPCs may serve as a valuable source of cells for cardiac repair due to their high cardiac differentiation potential and authentic cardiac origin. In order to generate an unlimited number of Isl1-CPCs, we used a previously established an ESC line that allows for isolation of Isl1-CPCs by green fluorescent protein (GFP expression that is directed by the mef2c gene, specifically expressed in the Isl1 domain of the anterior heart field. To improve the efficiency of cardiac differentiation of Isl1-CPCs, we studied the role of Bmp4 in cardiogenesis of Isl1-CPCs. We show an inductive role of Bmp directly on cardiac progenitors and its enhancement on early cardiac differentiation of CPCs. Upon induction of Bmp4 to Isl1-CPCs during differentiation, the cTnT+ cardiomyocyte population was enhanced 2.8±0.4 fold for Bmp4 treated CPC cultures compared to that detected for vehicle treated cultures. Both Bmp4 treated and untreated cardiomyocytes exhibit proper electrophysiological and calcium signaling properties. In addition, we observed a significant increase in Tbx5 and Tbx20 expression in differentiation cultures treated with Bmp4 compared to the untreated control, suggesting a link between Bmp4 and Tbx genes which may contribute to the enhanced cardiac differentiation in Bmp4 treated cultures. Collectively these findings suggest a cardiomyogenic role for Bmp4 directly on a pure population of

  14. Influence of Mussel-Derived Bioactive BMP-2-Decorated PLA on MSC Behavior in Vitro and Verification with Osteogenicity at Ectopic Sites in Vivo.

    Science.gov (United States)

    Chen, Zhuoyue; Zhang, Zhen; Feng, Juantao; Guo, Yayuan; Yu, Yuan; Cui, Jihong; Li, Hongmin; Shang, Lijun

    2018-04-11

    Osteoinductive activity of the implant in bone healing and regeneration is still a challenging research topic. Therapeutic application of recombinant human bone morphogenetic protein-2 (BMP-2) is a promising approach to enhance osteogenesis. However, high dose and uncontrolled burst release of BMP-2 may introduce edema, bone overgrowth, cystlike bone formation, and inflammation. In this study, low-dose BMP-2 of 1 μg was used to design PLA-PD-BMP for functionalization of polylactic acid (PLA) implants via mussel-inspired polydopamine (PD) assist. For the first time, the binding property and efficiency of the PD coating with BMP-2 were directly demonstrated and analyzed using an antigen-antibody reaction. The obtained PLA-PD-BMP surface immobilized with this low BMP-2 dose can endow the implants with abilities of introducing strong stem cell adhesion and enhanced osteogenicity. Furthermore, in vivo osteoinduction of the PLA-PD-BMP-2 scaffolds was confirmed by a rat ectopic bone model, which is marked as the "gold standard" for the evidence of osteoinductive activity. The microcomputed tomography, Young's modulus, and histology analyses were also employed to demonstrate that PLA-PD-BMP grafted with 1 μg of BMP-2 can induce bone formation. Therefore, the method in this study can be used as a model system to immobilize other growth factors onto various different types of polymer substrates. The highly biomimetic mussel-derived strategy can therefore improve the clinical outcome of polymer-based medical implants in a facile, safe, and effective way.

  15. The multifaceted effects of agmatine on functional recovery after spinal cord injury through Modulations of BMP-2/4/7 expressions in neurons and glial cells.

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    Yu Mi Park

    Full Text Available Presently, few treatments for spinal cord injury (SCI are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm, a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm(2 weight for 1 min at thoracic vertebra (Th 9 segment. Mice that received an intraperitoneal (i.p. injection of Agm (100 mg/kg/day within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following

  16. The Multifaceted Effects of Agmatine on Functional Recovery after Spinal Cord Injury through Modulations of BMP-2/4/7 Expressions in Neurons and Glial Cells

    Science.gov (United States)

    Park, Yu Mi; Lee, Won Taek; Bokara, Kiran Kumar; Seo, Su Kyoung; Park, Seung Hwa; Kim, Jae Hwan; Yenari, Midori A.; Park, Kyung Ah; Lee, Jong Eun

    2013-01-01

    Presently, few treatments for spinal cord injury (SCI) are available and none have facilitated neural regeneration and/or significant functional improvement. Agmatine (Agm), a guanidinium compound formed from decarboxylation of L-arginine by arginine decarboxylase, is a neurotransmitter/neuromodulator and been reported to exert neuroprotective effects in central nervous system injury models including SCI. The purpose of this study was to demonstrate the multifaceted effects of Agm on functional recovery and remyelinating events following SCI. Compression SCI in mice was produced by placing a 15 g/mm2 weight for 1 min at thoracic vertebra (Th) 9 segment. Mice that received an intraperitoneal (i.p.) injection of Agm (100 mg/kg/day) within 1 hour after SCI until 35 days showed improvement in locomotor recovery and bladder function. Emphasis was made on the analysis of remyelination events, neuronal cell preservation and ablation of glial scar area following SCI. Agm treatment significantly inhibited the demyelination events, neuronal loss and glial scar around the lesion site. In light of recent findings that expressions of bone morphogenetic proteins (BMPs) are modulated in the neuronal and glial cell population after SCI, we hypothesized whether Agm could modulate BMP- 2/4/7 expressions in neurons, astrocytes, oligodendrocytes and play key role in promoting the neuronal and glial cell survival in the injured spinal cord. The results from computer assisted stereological toolbox analysis (CAST) demonstrate that Agm treatment dramatically increased BMP- 2/7 expressions in neurons and oligodendrocytes. On the other hand, BMP- 4 expressions were significantly decreased in astrocytes and oligodendrocytes around the lesion site. Together, our results reveal that Agm treatment improved neurological and histological outcomes, induced oligodendrogenesis, protected neurons, and decreased glial scar formation through modulating the BMP- 2/4/7 expressions following SCI. PMID

  17. BMP4 and LGL1 are Down Regulated in an Ovine Model of Congenital Diaphragmatic Hernia

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    Heather eEmmerton-Coughlin

    2014-11-01

    Full Text Available Background/Purpose: The molecular pathophysiology of lung hypoplasia in congenital diaphragmatic hernia (CDH remains poorly understood. The Wnt signaling pathway and downstream targets, such as bone morphogenetic proteins (BMP 4 and other factors such as late gestation lung protein 1 (LGL1, are essential to normal lung development. Nitrofen-induced hypoplastic CDH rodent lungs demonstrate down regulation of the Wnt pathway including BMP4 and reduced LGL1 expression. The aim of the current study was to examine the molecular pathophysiology associated with a surgically induced CDH in an ovine model. Methods: Left thoracotomy was performed at 80 days in 14 fetal sheep; CDH was created in 7 experimental animals. Lungs were harvested at 136 days (term=145d. Lung weight and mean terminal bronchiole density (MTBD were measured to determine the degree of pulmonary hypoplasia. Quantitative real time PCR was undertaken to analyze Wnt2, Wnt7b, BMP4 and LGL1 mRNA expression. Results: Total lung weight was decreased while MTBD was increased in the CDH group (p<0.05, confirming pulmonary hypoplasia. BMP4 and LGL1 mRNA was significantly reduced in CDH lungs (p<0.05. Wnt2 mRNA was decreased, although not significantly (p<0.06. Conclusions: For the first time, down regulation of BMP4 and Lgl1 are reported in an ovine CDH model. In contrast to other animal models, these changes are persistent to near term. These findings suggest that mechanical compression from herniated viscera may play a more important role in causing pulmonary hypoplasia in CDH, rather than a primary defect in lung organogenesis.

  18. Study of the association between the BMP4 gene and congenital anomalies of the kidney and urinary tract

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    Geisilaine Soares dos Reis

    2014-01-01

    Conclusions: The present data suggest that Brazilian individuals with polymorphisms of the BMP4 gene have a higher risk to develop CAKUT, especially the malformations related to nephrogenesis and initial branching such as MDK and UPJO. Conversely, VUR appeared not to be related to BMP4 gene.

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

    International Nuclear Information System (INIS)

    Li Huiwu; Dai Kerong; Tang Tingting; Zhang Xiaoling; Yan Mengning; Lou Jueren

    2007-01-01

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

  20. Dexamethasone, BMP-2, and 1,25-dihydroxyvitamin D enhance a more differentiated osteoblast phenotype

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye; Henriksen, Z; Sørensen, O H

    2004-01-01

    . Osteoblast phenotypes were induced by either dexamethasone (Dex) or bone morphogenetic protein-2 (BMP-2). Bone marrow was obtained from biopsies at the posterior iliac spine. Cells were isolated by gradient centrifugation and grown to confluence. Cells were treated with 1 nM 1,25-dihydroxyvitamin D (vitamin...... activity was increased by Dex, but not by BMP-2 treatment. P1NP production was decreased after Dex treatment, while BMP-2 had no effect on P1NP levels. Osteocalcin production was low in cultures not stimulated with vitamin D. Dex or BMP-2 treatment alone did not affect the basic osteocalcin levels......, but in combination with vitamin D, BMP-2 increased the osteocalcin production, while Dex treatment completely suppressed osteocalcin production. Further, PTH-induced cAMP production was greatly enhanced by Dex treatment, whereas BMP-2 did not affect cAMP production. Finally, in vitro mineralization was greatly...

  1. Cell saver filtering of extravasated rhBMP-2 after degenerative scoliosis reconstruction

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    Gabriel Liu, MBBCh, MSc, FRCS, FAMS (Orth

    2015-06-01

    Full Text Available RhBMP-2 is a bone fusion enhancer commonly used in scoliosis reconstruction surgery. It is delivered via an absorbable collagen sponge but has been known to migrate away from its delivery site. RhBMP-2 extravasation in surgical drainage has been noted during first two days post-surgery. Cell savers are widely used in scoliosis reconstruction to limit transfusion requirements and are commonly deployed in cases where rhBMP-2 is used for fusion augmentation. It is not known whether rhBMP-2 is present in salvaged blood or filtered away during cell saver recycling. Through this case series of four patients who underwent scoliosis reconstruction, we assess cell saver efficacy in filtering rhBMP-2 molecules by quantifying the amount of rhBMP-2 present in salvaged blood obtained after postoperative drainage recycling by OrthoPAT® cell saver and comparing it to rhBMP-2 leakage in postoperative drainage without cell saver recycling. We report an almost 10-fold reduction of rhBMP-2 concentration in salvaged blood obtained after cell saver recycling of postoperative drainage, suggesting cell saver effectiveness in filtering rhBMP-2 molecules.

  2. Bmp2 deletion causes an amelogenesis imperfecta phenotype via regulating enamel gene expression.

    Science.gov (United States)

    Guo, Feng; Feng, Junsheng; Wang, Feng; Li, Wentong; Gao, Qingping; Chen, Zhuo; Shoff, Lisa; Donly, Kevin J; Gluhak-Heinrich, Jelica; Chun, Yong Hee Patricia; Harris, Stephen E; MacDougall, Mary; Chen, Shuo

    2015-08-01

    Although Bmp2 is essential for tooth formation, the role of Bmp2 during enamel formation remains unknown in vivo. In this study, the role of Bmp2 in regulation of enamel formation was investigated by the Bmp2 conditional knock out (Bmp2 cKO) mice. Teeth of Bmp2 cKO mice displayed severe and profound phenotypes with asymmetric and misshaped incisors as well as abrasion of incisors and molars. Scanning electron microscopy analysis showed that the enamel layer was hypoplastic and enamel lacked a typical prismatic pattern. Teeth from null mice were much more brittle as tested by shear and compressive moduli. Expression of enamel matrix protein genes, amelogenin, enamelin, and enamel-processing proteases, Mmp-20 and Klk4 was reduced in the Bmp2 cKO teeth as reflected in a reduced enamel formation. Exogenous Bmp2 up-regulated those gene expressions in mouse enamel organ epithelial cells. This result for the first time indicates Bmp2 signaling is essential for proper enamel development and mineralization in vivo. © 2015 Wiley Periodicals, Inc.

  3. Persistent expression of BMP-4 in embryonic chick adrenal cortical cells and its role in chromaffin cell development

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    Halbach Oliver

    2008-10-01

    Full Text Available Abstract Background Adrenal chromaffin cells and sympathetic neurons both originate from the neural crest, yet signals that trigger chromaffin development remain elusive. Bone morphogenetic proteins (BMPs emanating from the dorsal aorta are important signals for the induction of a sympathoadrenal catecholaminergic cell fate. Results We report here that BMP-4 is also expressed by adrenal cortical cells throughout chick embryonic development, suggesting a putative role in chromaffin cell development. Moreover, bone morphogenetic protein receptor IA is expressed by both cortical and chromaffin cells. Inhibiting BMP-4 with noggin prevents the increase in the number of tyrosine hydroxylase positive cells in adrenal explants without affecting cell proliferation. Hence, adrenal BMP-4 is likely to induce tyrosine hydroxylase in sympathoadrenal progenitors. To investigate whether persistent BMP-4 exposure is able to induce chromaffin traits in sympathetic ganglia, we locally grafted BMP-4 overexpressing cells next to sympathetic ganglia. Embryonic day 8 chick sympathetic ganglia, in addition to principal neurons, contain about 25% chromaffin-like cells. Ectopic BMP-4 did not increase this proportion, yet numbers and sizes of 'chromaffin' granules were significantly increased. Conclusion BMP-4 may serve to promote specific chromaffin traits, but is not sufficient to convert sympathetic neurons into a chromaffin phenotype.

  4. BMP4 and FGF3 haplotypes increase the risk of tendinopathy in volleyball athletes.

    Science.gov (United States)

    Salles, José Inácio; Amaral, Marcus Vinícius; Aguiar, Diego Pinheiro; Lira, Daisy Anne; Quinelato, Valquiria; Bonato, Letícia Ladeira; Duarte, Maria Eugenia Leite; Vieira, Alexandre Rezende; Casado, Priscila Ladeira

    2015-03-01

    To investigate whether genetic variants can be correlated with tendinopathy in elite male volleyball athletes. Case-control study. Fifteen single nucleotide polymorphisms within BMP4, FGF3, FGF10, FGFR1 genes were investigated in 138 elite volleyball athletes, aged between 18 and 35 years, who undergo 4-5h of training per day: 52 with tendinopathy and 86 with no history of pain suggestive of tendinopathy in patellar, Achilles, shoulder, and hip abductors tendons. The clinical diagnostic criterion was progressive pain during training, confirmed by magnetic resonance image. Genomic DNA was obtained from saliva samples. Genetic markers were genotyped using TaqMan real-time PCR. Chi-square test compared genotypes and haplotype differences between groups. Multivariate logistic regression analyzed the significance of covariates and incidence of tendinopathy. Statistical analysis revealed participant age (p=0.005) and years of practice (p=0.004) were risk factors for tendinopathy. A significant association between BMP4 rs2761884 (p=0.03) and tendinopathy was observed. Athletes with a polymorphic genotype have 2.4 times more susceptibility to tendinopathy (OR=2.39; 95%CI=1.10-5.19). Also, association between disease and haplotype TTGGA in BMP4 (p=0.01) was observed. The FGF3 TGGTA haplotype showed a tendency of association with tendinopathy (p=0.05), and so did FGF10 rs900379. FGFR1 showed no association with disease. These findings indicate that haplotypes in BMP4 and FGF3 genes may contribute to the tendon disease process in elite volleyball athletes. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  5. Polymorphism of BMP4 gene in Indian goat breeds differing in prolificacy.

    Science.gov (United States)

    Sharma, Rekha; Ahlawat, Sonika; Maitra, A; Roy, Manoranjan; Mandakmale, S; Tantia, M S

    2013-12-10

    Bone morphogenetic proteins (BMPs) are members of the TGF-β (transforming growth factor-beta) superfamily, of which BMP4 is the most important due to its crucial role in follicular growth and differentiation, cumulus expansion and ovulation. Reproduction is a crucial trait in goat breeding and based on the important role of BMP4 gene in reproduction it was considered as a possible candidate gene for the prolificacy of goats. The objective of the present study was to detect polymorphism in intronic, exonic and 3' un-translated regions of BMP4 gene in Indian goats. Nine different goat breeds (Barbari, Beetal, Black Bengal, Malabari, Jakhrana (Twinning>40%), Osmanabadi, Sangamneri (Twinning 20-30%), Sirohi and Ganjam (Twinning<10%)) differing in prolificacy and geographic distribution were employed for polymorphism scanning. Cattle sequence (AC_000167.1) was used to design primers for the amplification of a targeted region followed by direct DNA sequencing to identify the genetic variations. Single nucleotide polymorphisms (SNPs) were not detected in exon 3, the intronic region and the 3' flanking region. A SNP (G1534A) was identified in exon 2. It was a non-synonymous mutation resulting in an arginine to lysine change in a corresponding protein sequence. G to A transition at the 1534 locus revealed two genotypes GG and GA in the nine investigated goat breeds. The GG genotype was predominant with a genotype frequency of 0.98. The GA genotype was present in the Black Bengal as well as Jakhrana breed with a genotype frequency of 0.02. A microsatellite was identified in the 3' flanking region, only 20 nucleotides downstream from the termination site of the coding region, as a short sequence with more than nineteen continuous and repeated CA dinucleotides. Since the gene is highly evolutionarily conserved, identification of a non-synonymous SNP (G1534A) in the coding region gains further importance. To our knowledge, this is the first report of a mutation in the coding

  6. Alveolar ridge and maxillary sinus augmentation using rhBMP-2: a systematic review.

    Science.gov (United States)

    Freitas, Rubens Moreno de; Spin-Neto, Rubens; Marcantonio Junior, Elcio; Pereira, Luís Antônio Violin Dias; Wikesjö, Ulf M E; Susin, Cristiano

    2015-01-01

    The aim of this systematic review was to evaluate clinical and safety data for recombinant human bone morphogenetic protein-2 (rhBMP-2) in an absorbable collagen sponge (ACS) carrier when used for alveolar ridge/maxillary sinus augmentation in humans. Clinical studies/case series published 1980 through June 2012 using rhBMP-2/ACS were searched. Studies meeting the following criteria were considered eligible for inclusion: >10 subjects at baseline and maxillary sinus or alveolar ridge augmentation not concomitant with implant placement. Seven of 69 publications were eligible for review. rhBMP-2/ACS yielded clinically meaningful bone formation for maxillary sinus augmentation that would allow placement of regular dental implants without consistent differences between rhBMP-2 concentrations. Nevertheless, the statistical analysis showed that sinus augmentation following autogenous bone graft was significantly greater (mean bone height: 1.6 mm, 95% CI: 0.5-2.7 mm) than for rhBMP-2/ACS (rhBMP-2 at 1.5 mg/mL). In extraction sockets, rhBMP-2/ACS maintained alveolar ridge height while enhancing alveolar ridge width. Safety reports did not represent concerns for the proposed indications. rhBMP-2/ACS appears a promising alternative to autogenous bone grafts for alveolar ridge/maxillary sinus augmentation; dose and carrier optimization may expand its efficacy, use, and clinical application. © 2013 Wiley Periodicals, Inc.

  7. Construction of doxycycline-mediated BMP-2 transgene combining with APA microcapsules for bone repair.

    Science.gov (United States)

    Qian, Dongyang; Bai, Bo; Yan, Guangbin; Zhang, Shujiang; Liu, Qi; Chen, Yi; Tan, Xiaobo; Zeng, Yanjun

    2016-01-01

    The repairing of large segmental bone defects is difficult for clinical orthopedists at present. Gene therapy is regarded as a promising method for bone defects repair. The present study aimed to construct an effective and controllable Tet-On expression system for transferring hBMP-2 gene into bone marrow mesenchymal progenitor cells (BMSCs). Meanwhile, with combination of alginate-poly-L-lysine-alginate (APA) microencapsulation technology, we attempted to reduce the influence of immunologic rejection and examine the effect of the Tet-On expression system on osteogenesis of BMSCs. The adenovirus encoding hBMP-2 (ADV-hBMP2) was constructed using the means of molecular cloning. The ADV-hBMP2 and Adeno-X Tet-On virus was respectively transfected to the HEK293 for amplification and afterward BMSCs were co-infected with the virus of ADV-hBMP2 and the Adeno-X Tet-On. The expression of hBMP-2 was measured with induction by doxycycline (DOX) at different concentration by means of RT-PCR and ELISA. Combining Tet-On expression system and APA microcapsules with the use of the pulsed high-voltage electrostatic microcapsule instrument, we examined the expression level of hBMP-2 in APA microcapsules by ELISA as well as the osteogenesis by alizarin red S staining. An effective Tet-On expression system for transferring hBMP-2 gene into BMSCs was constructed successfully. Also, the expression of hBMP-2 could be regulated by concentration of DOX. The data exhibited that BMSCs in APA microcapsules maintained the capability of proliferation and differentiation. The combination of Tet-On expression system and APA microcapsules could promote the osteogenesis of BMSCs. According to the results, microencapsulated Tet-On expression system showed the effective characteristics of secreting hBMP-2 and enhancing osteogenesis, which would provide a promising way for bone repair.

  8. Effect of growth factors (BMP-4/7 & bFGF on proliferation & osteogenic differentiation of bone marrow stromal cells

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    Shaohui Yuan

    2013-01-01

    Full Text Available Background & objectives: BMP (bone morphogenetic protein-4/7 and bFGF (basic fibroblast growth factor significantly promote the osteogenic activity and the proliferation of rabbit BMSCs (bone marrow stromal cells, respectively. However, their synergistic effects on the proliferation and the differentiation of BMSCs remain unclear. In the present study, the effects of bFGF and BMP-4/7 were investigated on the proliferation and the differentiation of rat BMSCs in vitro. Methods: BMSCs were isolated from New Zealand white rabbits and cultured to the third passage. The samples were divided into five groups according to the material implanted: (A 80 ng/ml BMP-4/7; (B 80 ng/ml bFGF; (C 30 ng/ml BMP-4/7 and 30 ng/ml bFGF; (D 50 ng/ml BMP-4/7 and 50 ng/ml bFGF; and (E 80 ng/ml BMP-4/7 and 80 ng/ml bFGF. Cell proliferation was analyzed using methyl thiazolyl tetrazolium (MTT assay. Alkaline phosphatase activity and osteocalcin (OC dynamics were also measured. Results: BMP-4/7 alone significantly (P<0.05 promoted the proliferation of BMSCs. At the same time, it also promoted or inhibited the osteogenic differentiation of BMSCs. The synergistic effects of BMP-4/7 and bFGF significantly promoted both the proliferation and the osteogenic differentiation of BMSCs. The treatment of the synergistic effects was dose and time dependent. Interpretation & conclusions: A rational combination of BMP-4/7 and bFGF can promote the proliferation and the osteogenic differentiation of BMSCs. In addition, the synergistic functions are effective.

  9. Mutation of Rubie, a novel long non-coding RNA located upstream of Bmp4, causes vestibular malformation in mice.

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    Kristina A Roberts

    Full Text Available The vestibular apparatus of the vertebrate inner ear uses three fluid-filled semicircular canals to sense angular acceleration of the head. Malformation of these canals disrupts the sense of balance and frequently causes circling behavior in mice. The Epistatic circler (Ecl is a complex mutant derived from wildtype SWR/J and C57L/J mice. Ecl circling has been shown to result from the epistatic interaction of an SWR-derived locus on chromosome 14 and a C57L-derived locus on chromosome 4, but the causative genes have not been previously identified.We developed a mouse chromosome substitution strain (CSS-14 that carries an SWR/J chromosome 14 on a C57BL/10J genetic background and, like Ecl, exhibits circling behavior due to lateral semicircular canal malformation. We utilized CSS-14 to identify the chromosome 14 Ecl gene by positional cloning. Our candidate interval is located upstream of bone morphogenetic protein 4 (Bmp4 and contains an inner ear-specific, long non-coding RNA that we have designated Rubie (RNA upstream of Bmp4 expressed in inner ear. Rubie is spliced and polyadenylated, and is expressed in developing semicircular canals. However, we discovered that the SWR/J allele of Rubie is disrupted by an intronic endogenous retrovirus that causes aberrant splicing and premature polyadenylation of the transcript. Rubie lies in the conserved gene desert upstream of Bmp4, within a region previously shown to be important for inner ear expression of Bmp4. We found that the expression patterns of Bmp4 and Rubie are nearly identical in developing inner ears.Based on these results and previous studies showing that Bmp4 is essential for proper vestibular development, we propose that Rubie is the gene mutated in Ecl mice, that it is involved in regulating inner ear expression of Bmp4, and that aberrant Bmp4 expression contributes to the Ecl phenotype.

  10. BMP4 Expression Following Stem Cells from Human Exfoliated Deciduous and Carbonate Apatite Transplantation on Rattus norvegicus

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    Tania Saskianti

    2018-04-01

    Full Text Available Background: Alveolar bone defects in children still have a high incidence. Conventional bone graft technique that has been used as a defect therapy is still not effective, so new techniques with tissue engineering approach are needed. Bone Morphogenetic Protein 4 (BMP4 as one of the indicators of osteogenic differentiation has not been widely studied, especially in the transplantation with combination of Stem Cells from Human Exfoliated Deciduous (SHED and carbonate apatite. Aim and Objectives: This research aimed to determine the expression of BMP4 after SHED and carbonate apatite transplantation on Rattus norvegicus. Material and Methods: The combinations of SHED and carbonate apatite were transplanted on alveolar bone defects of 4 rats (Rattus norvegicus as the treatment groups and another 4 rats were transplanted with carbonate apatite as the control groups. After 21 days, staining with Hematoxylin Eosin (HE and Immunohistochemistry (IHC BMP4 was performed. Results: BMP4 expression in the treatment groups was significantly higher when compared to the control groups. Discussion: Carbonate apatite has low crystallization rate and high osteoconductivity that produce more osteoblasts and increased BMP4 expression. Conclusion: The transplantation of SHED and carbonate apatite increased BMP4 expression as an indicator of osteogenic differentiation in rats.

  11. Comparison of the osteogenesis and fusion rates between activin A/BMP-2 chimera (AB204) and rhBMP-2 in a beagle's posterolateral lumbar spine model.

    Science.gov (United States)

    Zheng, Guang Bin; Yoon, Byung-Hak; Lee, Jae Hyup

    2017-10-01

    Activin A/BMP-2 chimera (AB204) could promote bone healing more effectively than recombinant bone morphogenetic protein 2 (rhBMP-2) with much lower dose in a rodent model, but there is no report about the effectiveness of AB204 in a large animal model. The purpose of this study was to compare the osteogenesis and fusion rate between AB204 and rhBMP-2 using biphasic calcium phosphate (BCP) as a carrier in a beagle's posterolateral lumbar fusion model. This is a randomized control animal study. Seventeen male beagle dogs were included. Bilateral posterolateral fusion was performed at the L1-L2 and L4-L5 levels. Biphasic calcium phosphate (2 cc), rhBMP-2 (50 µg)+BCP (2 cc), or AB204 (50 µg)+BCP (2 cc) were implanted into the intertransverse space randomly. X-ray was performed at 4 and 8 weeks. After 8 weeks, the animals were sacrificed, and new bone formation and fusion rate were evaluated by manual palpation, computed tomography (CT), and undecalcified histology. The AB204 group showed significantly higher fusion rate (90%) than the rhBMP-2 group (15%) or the Osteon group (6.3%) by manual palpation. On x-ray and CT assessment, fusion rate and the volume of newly formed bone were also significantly higher in AB204 group than other groups. In contrast, more osteolysis was found in rhBMP-2 group (40%) than in AB204 group (10%) on CT study. In histologic results, new bone formation was sufficient between transverse processes in AB204 group, and obvious trabeculation and bone remodeling were observed. But in rhBMP-2 group, new bone formation was less than AB204 group and osteolysis was observed between the intertransverse spaces. A low dose of AB204 with BCP as a carrier significantly promotes the fusion rate in a large animal model when compared with the rhBMP-2. These findings demonstrate that AB204 could be an alternative to rhBMP-2 to improve fusion rate. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Low-intensity pulsed ultrasound accelerates tooth movement via activation of the BMP-2 signaling pathway.

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    Hui Xue

    Full Text Available The present study was designed to determine the underlying mechanism of low-intensity pulsed ultrasound (LIPUS induced alveolar bone remodeling and the role of BMP-2 expression in a rat orthodontic tooth movement model. Orthodontic appliances were placed between the homonymy upper first molars and the upper central incisors in rats under general anesthesia, followed by daily 20-min LIPUS or sham LIPUS treatment beginning at day 0. Tooth movement distances and molecular changes were evaluated at each observation point. In vitro and in vivo studies were conducted to detect HGF (Hepatocyte growth factor/Runx2/BMP-2 signaling pathways and receptor activator of NFκB ligand (RANKL expression by quantitative real time PCR (qRT-PCR, Western blot and immunohistochemistry. At day 3, LIPUS had no effect on the rat orthodontic tooth movement distance and BMP-2-induced alveolar bone remodeling. However, beginning at day 5 and for the following time points, LIPUS significantly increased orthodontic tooth movement distance and BMP-2 signaling pathway and RANKL expression compared with the control group. The qRT-PCR and Western blot data in vitro and in vivo to study BMP-2 expression were consistent with the immunohistochemistry observations. The present study demonstrates that LIPUS promotes alveolar bone remodeling by stimulating the HGF/Runx2/BMP-2 signaling pathway and RANKL expression in a rat orthodontic tooth movement model, and LIPUS increased BMP-2 expression via Runx2 regulation.

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

    Science.gov (United States)

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

    2015-01-01

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

  14. Immobilization of Murine Anti-BMP-2 Monoclonal Antibody on Various Biomaterials for Bone Tissue Engineering

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    Sahar Ansari

    2014-01-01

    Full Text Available Biomaterials are widely used as scaffolds for tissue engineering. We have developed a strategy for bone tissue engineering that entails application of immobilized anti-BMP-2 monoclonal antibodies (mAbs to capture endogenous BMPs in vivo and promote antibody-mediated osseous regeneration (AMOR. The purpose of the current study was to compare the efficacy of immobilization of a specific murine anti-BMP-2 mAb on three different types of biomaterials and to evaluate their suitability as scaffolds for AMOR. Anti-BMP-2 mAb or isotype control mAb was immobilized on titanium (Ti microbeads, alginate hydrogel, and ACS. The treated biomaterials were surgically implanted in rat critical-sized calvarial defects. After 8 weeks, de novo bone formation was assessed using micro-CT and histomorphometric analyses. Results showed de novo bone regeneration with all three scaffolds with immobilized anti-BMP-2 mAb, but not isotype control mAb. Ti microbeads showed the highest volume of bone regeneration, followed by ACS. Alginate showed the lowest volume of bone. Localization of BMP-2, -4, and -7 antigens was detected on all 3 scaffolds with immobilized anti-BMP-2 mAb implanted in calvarial defects. Altogether, these data suggested a potential mechanism for bone regeneration through entrapment of endogenous BMP-2, -4, and -7 proteins leading to bone formation using different types of scaffolds via AMOR.

  15. BMP-2 Induced Expression of Alx3 That Is a Positive Regulator of Osteoblast Differentiation.

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    Takashi Matsumoto

    Full Text Available Bone morphogenetic proteins (BMPs regulate many aspects of skeletal development, including osteoblast and chondrocyte differentiation, cartilage and bone formation, and cranial and limb development. Among them, BMP-2, one of the most potent osteogenic signaling molecules, stimulates osteoblast differentiation, while it inhibits myogenic differentiation in C2C12 cells. To evaluate genes involved in BMP-2-induced osteoblast differentiation, we performed cDNA microarray analyses to compare BMP-2-treated and -untreated C2C12 cells. We focused on Alx3 (aristaless-like homeobox 3 which was clearly induced during osteoblast differentiation. Alx3, a homeobox gene related to the Drosophilaaristaless gene, has been linked to developmental functions in craniofacial structures and limb development. However, little is known about its direct relationship with bone formation. In the present study, we focused on the mechanisms of Alx3 gene expression and function during osteoblast differentiation induced by BMP-2. In C2C12 cells, BMP-2 induced increase of Alx3 gene expression in both time- and dose-dependent manners through the BMP receptors-mediated SMAD signaling pathway. In addition, silencing of Alx3 by siRNA inhibited osteoblast differentiation induced by BMP-2, as showed by the expressions of alkaline phosphatase (Alp, Osteocalcin, and Osterix, while over-expression of Alx3 enhanced osteoblast differentiation induced by BMP-2. These results indicate that Alx3 expression is enhanced by BMP-2 via the BMP receptors mediated-Smad signaling and that Alx3 is a positive regulator of osteoblast differentiation induced by BMP-2.

  16. BMP-2 Overexpression Augments Vascular Smooth Muscle Cell Motility by Upregulating Myosin Va via Erk Signaling

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    Ming Zhang

    2014-01-01

    Full Text Available Background. The disruption of physiologic vascular smooth muscle cell (VSMC migration initiates atherosclerosis development. The biochemical mechanisms leading to dysfunctional VSMC motility remain unknown. Recently, cytokine BMP-2 has been implicated in various vascular physiologic and pathologic processes. However, whether BMP-2 has any effect upon VSMC motility, or by what manner, has never been investigated. Methods. VSMCs were adenovirally transfected to genetically overexpress BMP-2. VSMC motility was detected by modified Boyden chamber assay, confocal time-lapse video assay, and a colony wounding assay. Gene chip array and RT-PCR were employed to identify genes potentially regulated by BMP-2. Western blot and real-time PCR detected the expression of myosin Va and the phosphorylation of extracellular signal-regulated kinases 1/2 (Erk1/2. Immunofluorescence analysis revealed myosin Va expression locale. Intracellular Ca2+ oscillations were recorded. Results. VSMC migration was augmented in VSMCs overexpressing BMP-2 in a dose-dependent manner. siRNA-mediated knockdown of myosin Va inhibited VSMC motility. Both myosin Va mRNA and protein expression significantly increased after BMP-2 administration and were inhibited by Erk1/2 inhibitor U0126. BMP-2 induced Ca2+ oscillations, generated largely by a “cytosolic oscillator”. Conclusion. BMP-2 significantly increased VSMCs migration and myosin Va expression, via the Erk signaling pathway and intracellular Ca2+ oscillations. We provide additional insight into the pathophysiology of atherosclerosis, and inhibition of BMP-2-induced myosin Va expression may represent a potential therapeutic strategy.

  17. Site-Directed Immobilization of BMP-2: Two Approaches for the Production of Innovative Osteoinductive Scaffolds.

    Science.gov (United States)

    Tabisz, Barbara; Schmitz, Werner; Schmitz, Michael; Luehmann, Tessa; Heusler, Eva; Rybak, Jens-Christoph; Meinel, Lorenz; Fiebig, Juliane E; Mueller, Thomas D; Nickel, Joachim

    2017-03-13

    The regenerative potential of bone is strongly impaired in pathological conditions, such as nonunion fractures. To support bone regeneration various scaffolds have been developed in the past, which have been functionalized with osteogenic growth factors such as bone morphogenetic proteins (BMPs). However, most of them required supra-physiological levels of these proteins leading to burst releases, thereby causing severe side effects. Site-specific, covalent coupling of BMP2 to implant materials might be an optimal strategy in order to overcome these problems. Therefore, we created a BMP-2 variant (BMP2-K3Plk) containing a noncanonical amino acid (propargyl-l-lysine) substitution introduced by genetic code expansion that allows for site-specific and covalent immobilization onto polymeric scaffold materials. To directly compare different coupling strategies, we also produced a BMP2 variant containing an additional cysteine residue (BMP2-A2C) allowing covalent coupling by thioether formation. The BMP2-K3Plk mutant was coupled to functionalized beads by a copper-catalyzed azide-alkyne cycloaddition (CuAAC) either directly or via a short biotin-PEG linker both with high specificity. After exposing the BMP-coated beads to C2C12 cells, ALP expression appeared locally restricted in close proximity to these beads, showing that both coupled BMP2 variants trigger cell differentiation. The advantage of our approach over non-site-directed immobilization techniques is the ability to produce fully defined osteogenic surfaces, allowing for lower BMP2 loads and concomitant higher bioactivities, for example, due to controlled orientation toward BMP2 receptors. Such products might provide superior bone healing capabilities with potential safety advantages as of homogeneous product outcome.

  18. Smad, PI3K/Akt, and Wnt-dependent signaling pathways are involved in BMP-4-induced ESC self-renewal.

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    Lee, Min Young; Lim, Hyun Woo; Lee, Sang Hun; Han, Ho Jae

    2009-08-01

    It is known that bone morphogenetic protein 4 (BMP-4) has a diverse effect on ESCs. However, its precise mechanism in mouse ESCs is not fully understood. We evaluated the effect of BMP-4 on ESC proliferation and its related signal cascades in this study. BMP-4 significantly increased the level of [(3)H]-thymidine incorporation in time- (> or =8 hours) and dose- (> or =10 ng/ml) dependent manners. Additionally, BMP-4 increased cyclin D1 and decreased p27(kip1) expression values in a time-dependent manner. The increases in BMP-4-induced [(3)H]-thymidine incorporation and cyclin D1 expression were inhibited by the BMP-4 receptor antagonist noggin. BMP-4 increased Wnt1 expression. Wnt1 expression was attenuated by Smad4 small interfering RNA (siRNA), and BMP-4-induced cyclin D1 expression was inhibited by Smad4 and Wnt1 siRNAs. BMP-4 also activated beta-catenin, which was blocked by Smad4 and Wnt1 siRNAs. In addition, BMP-4 induced Akt phosphorylation. BMP-4-induced beta-catenin activation and cyclin D1 expression were attenuated by phosphatidyl inositol 3-kinase (PI3K) siRNA and Akt inhibitor. Additionally, downregulation of Smad4, Wnt1, and PI3K expression by siRNA decreased the levels of pluripotency marker mRNAs of ESCs, including Oct4, Sox2, and FoxD3. Our results suggested that BMP-4-induced [(3)H]-thymidine incorporation was significantly attenuated by Smad4, Wnt1, and PI3K knockdown. In conclusion, BMP-4 contributed to the maintenance of cell proliferation and the pluripotent state by Smad, PI3K/Akt, and Wnt1/beta-catenin in mouse ESCs.

  19. Differentiation of Odontoblast-Like Cells From Mouse Induced Pluripotent Stem Cells by Pax9 and Bmp4 Transfection.

    Science.gov (United States)

    Seki, Daisuke; Takeshita, Nobuo; Oyanagi, Toshihito; Sasaki, Shutaro; Takano, Ikuko; Hasegawa, Masakazu; Takano-Yamamoto, Teruko

    2015-09-01

    The field of tooth regeneration has progressed in recent years, and human tooth regeneration could become viable in the future. Because induced pluripotent stem (iPS) cells can differentiate into odontogenic cells given appropriate conditions, iPS cells are a potential cell source for tooth regeneration. However, a definitive method to induce iPS cell-derived odontogenic cells has not been established. We describe a novel method of odontoblast differentiation from iPS cells using gene transfection. We generated mouse iPS cell-derived neural crest-like cells (iNCLCs), which exhibited neural crest markers. Next, we differentiated iNCLCs into odontoblast-like cells by transfection of Pax9 and Bmp4 expression plasmids. Exogenous Pax9 upregulated expression of Msx1 and dentin matrix protein 1 (Dmp1) in iNCLCs but not bone morphogenetic protein 4 (Bmp4) or dentin sialophosphoprotein (Dspp). Exogenous Bmp4 upregulated expression of Msx1, Dmp1, and Dspp in iNCLCs, but not Pax9. Moreover, cotransfection of Pax9 and Bmp4 plasmids in iNCLCs revealed a higher expression of Pax9 than when Pax9 plasmid was used alone. In contrast, exogenous Pax9 downregulated Bmp4 overexpression. Cotransfection of Pax9 and Bmp4 synergistically upregulated Dmp1 expression; however, Pax9 overexpression downregulated exogenous Bmp4-induced Dspp expression. Together, these findings suggest that an interaction between exogenous Pax9- and Bmp4-induced signaling modulated Dmp1 and Dspp expression. In conclusion, transfection of Pax9 and Bmp4 expression plasmids in iNCLCs induced gene expression associated with odontoblast differentiation, suggesting that iNCLCs differentiated into odontoblast-like cells. The iPS cell-derived odontoblast-like cells could be a useful cell source for tooth regeneration. It has been reported that induced pluripotent stem (iPS) cells differentiate into odontogenic cells by administration of recombinant growth factors and coculture with odontogenic cells. Therefore, they can

  20. Inactivation of Bmp4 from the Tbx1 Expression Domain Causes Abnormal Pharyngeal Arch Artery and Cardiac Outflow Tract Remodeling

    Science.gov (United States)

    Nie, Xuguang; Brown, Christopher B.; Wang, Qin; Jiao, Kai

    2011-01-01

    Maldevelopment of outflow tract and aortic arch arteries is among the most common forms of human congenital heart diseases. Both Bmp4 and Tbx1 are known to play critical roles during cardiovascular development. Expression of these two genes partially overlaps in pharyngeal arch areas in mouse embryos. In this study, we applied a conditional gene inactivation approach to test the hypothesis that Bmp4 expressed from the Tbx1 expression domain plays a critical role for normal development of outflow tract and pharyngeal arch arteries. We showed that inactivation of Bmp4 from Tbx1-expressing cells leads to the spectrum of deformities resembling the cardiovascular defects observed in human DiGeorge syndrome patients. Inactivation of Bmp4 from the Tbx1 expression domain did not cause patterning defects, but affected remodeling of outflow tract and pharyngeal arch arteries. Our further examination revealed that Bmp4 is required for normal recruitment/differentiation of smooth muscle cells surrounding the PAA4 and survival of outflow tract cushion mesenchymal cells. PMID:21123999

  1. Microparticle-Mediated Delivery of BMP4 for Generation of Meiosis-Competent Germ Cells from Embryonic Stem Cells.

    Science.gov (United States)

    Esfandiari, Fereshteh; Ashtiani, Mohammad Kazemi; Sharifi-Tabar, Mehdi; Saber, Maryam; Daemi, Hamed; Ghanian, Mohammad Hossein; Shahverdi, Abdolhossein; Baharvand, Hossein

    2017-03-01

    Producing meiosis-competent germ cells (GCs) from embryonic stem cells (ESCs) is essential for developing advanced therapies for infertility. Here, a novel approach is presented for generation of GCs from ESCs. In this regard, microparticles (MPs) have been developed from alginate sulfate loaded with bone morphogenetic protein 4 (BMP4). The results here show that BMP4 release from alginate sulfate MPs is significantly retarded by the sulfated groups compared to neat alginate. Then, BMP4-laden MPs are incorporated within the aggregates during differentiation of GCs from ESCs. It is observed that BMP4-laden MPs increase GC differentiation from ESCs at least twofold compared to the conventional soluble delivery method. Interestingly, following meiosis induction, Dazl, an intrinsic factor that enables GCs to enter meiosis, and two essential meiosis genes (Stra8 and Smc1b) are upregulated significantly in MP-induced aggregates compared to aggregates, which are formed by the conventional method. Together, these data show that controlled delivery of BMP4 during ESC differentiation into GC establish meiosis-competent GCs which can serve as an attractive GC source for reproductive medicine. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Photobiomodulation of mesenchymal stem cells encapsulated in an injectable rhBMP4-loaded hydrogel directs hard tissue bioengineering.

    Science.gov (United States)

    Diniz, Ivana M A; Carreira, Ana C O; Sipert, Carla R; Uehara, Cindi M; Moreira, Maria S N; Freire, Laila; Pelissari, Cibele; Kossugue, Patrícia M; de Araújo, Daniele R; Sogayar, Mari C; Marques, Márcia M

    2018-06-01

    Photobiomodulation (PBM) therapy displays relevant properties for tissue healing and regeneration, which may be of interest for the tissue engineering field. Here, we show that PBM is able to improve cell survival and to interact with recombinant human Bone Morphogenetic Protein 4 (rhBMP4) to direct and accelerate odonto/osteogenic differentiation of dental derived mesenchymal stem cells (MSCs). MSCs were encapsulated in an injectable and thermo-responsive cell carrier (Pluronic ® F-127) loaded with rhBMP4 and then photoactivated. PBM improved MSCs self-renewal and survival upon encapsulation in the Pluronic ® F-127. In the presence of rhBMP4, cell odonto/osteogenic differentiation was premature and markedly improved in the photoactivated MSCs. An in vivo calvarial critical sized defect model demonstrated significant increase in bone formation after PBM treatment. Finally, a balance in the reactive oxygen species levels may be related to the favorable results of PBM and rhBMP4 association. PBM may act in synergism with rhBMP4 and is a promise candidate to direct and accelerate hard tissue bioengineering. © 2017 Wiley Periodicals, Inc.

  3. BMP-2 induces EMT and breast cancer stemness through Rb and CD44

    DEFF Research Database (Denmark)

    Huang, Peide; Chen, Anan; He, Weiyi

    2017-01-01

    Bone morphogenetic protein 2 (BMP-2) has been reported to facilitate epithelial-to-mesenchymal transition (EMT) and bone metastasis in breast cancer xenograft models. To investigate the role of BMP-2 in the development of breast cancer stem cells (BCSCs), and to further elucidate the mechanisms u...... then contribute to breast cancer metastasis. These findings may be helpful for developing new strategies for the treatment and prognosis of advanced breast cancer....

  4. Surface Modification of Titanium with BMP-2/GDF-5 by a Heparin Linker and Its Efficacy as a Dental Implant

    Directory of Open Access Journals (Sweden)

    Dae Hyeok Yang

    2017-01-01

    Full Text Available In this study, we prepared human bone morphogenetic protein-2 (hBMP-2/human growth and differentiation factor-5 (hGDF-5-coated titanium (Ti disc and screw types for controlled release of the growth factors (GFs. The two growth factors were coated onto Ti with a smooth surface using their specific interaction with heparin, because they have heparin binding sites in their molecular structures. Efficacy of the two growth factor-coated Ti for enhancement of bone formation and osseointegration was compared to pristine Ti, and hBMP-2- and hGDF-5-coated Ti in vivo. The surface chemical composition, surface morphology, and wettability characteristics of the metal samples were determined by X-ray photoelectron spectroscopy (XPS, scanning electron microscopy (SEM, and contact angle measurement, respectively. The initial burst of hBMP-2, hGDF-5, and their combination, occurred within one day of the release study, resulting in 12.5%, 4.5%, and 13.5%/3.2%, and then there was a sustained, even release of these two growth factors from the coated metal for 30 days. In vitro tests revealed that MC3T3-E1 cells cultured on the two growth factor-coated Ti had a higher proliferation rate and a higher activity for alkaline phosphatase (ALP, which led to a larger amount of calcium deposition and larger expressions of type I collagen (COL 1, ALP, and osteocalcin (OCN mRNAs. In vivo animal tests using ten white New Zealand rabbits showed that the two growth factor-coated Ti enhanced bone formation and osseointegration at the interface between the implants and host bone. In addition, histological evaluation showed that bone remodeling, including bone formation by osteoblasts and bone resorption by osteoclasts, actively occurred between the two growth factor-coated Ti and host bone. Consequently, it is suggested that Ti surface modification with the combination of hBMP-2 and hGDF-5 for the two growth factor-coated Ti implants can improve the clinical properties of

  5. Bmp 2 and bmp 7 induce odonto- and osteogenesis of human tooth germ stem cells.

    Science.gov (United States)

    Taşlı, P Neslihan; Aydın, Safa; Yalvaç, Mehmet Emir; Sahin, Fikrettin

    2014-03-01

    Bone morphogenetic proteins (BMPs) initiate, promote, and maintain odontogenesis and osteogenesis. In this study, we studied the effect of bone morphogenic protein 2 (BMP 2) and bone morphogenic protein 7 (BMP 7) as differentiation inducers in tooth and bone regeneration. We compared the effect of BMP 2 and BMP 7 on odontogenic and osteogenic differentiation of human tooth germ stem cells (hTGSCs). Third molar-derived hTGSCs were characterized with mesenchymal stem cell surface markers by flow cytometry. BMP 2 and BMP 7 were transfected into hTGSCs and the cells were seeded onto six-well plates. One day after the transfection, hTGSCs were treated with odontogenic and osteogenic mediums for 14 days. For confirmation of odontogenic and osteogenic differentiation, mRNA levels of BMP2, BMP 7, collagen type 1 (COL1A), osteocalsin (OCN), and dentin sialophosphoprotein (DSPP) genes were measured by quantitative real-time PCR. In addition to this, immunocytochemistry was performed by odontogenic and osteogenic antibodies and mineralization obtained by von Kossa staining. Our results showed that the BMP 2 and BMP 7 both promoted odontogenic and osteogenic differentiation of hTGSCs. Data indicated that BMP 2 treatment and BMP 7 treatment induce odontogenic differentiation without affecting each other, whereas they induce osteogenic differentiation by triggering expression of each other. These findings provide a feasible tool for tooth and bone tissue engineering.

  6. Sustained release of BMP-2 in bioprinted alginate for osteogenicity in mice and rats.

    Directory of Open Access Journals (Sweden)

    Michelle T Poldervaart

    Full Text Available The design of bioactive three-dimensional (3D scaffolds is a major focus in bone tissue engineering. Incorporation of growth factors into bioprinted scaffolds offers many new possibilities regarding both biological and architectural properties of the scaffolds. This study investigates whether the sustained release of bone morphogenetic protein 2 (BMP-2 influences osteogenicity of tissue engineered bioprinted constructs. BMP-2 loaded on gelatin microparticles (GMPs was used as a sustained release system, which was dispersed in hydrogel-based constructs and compared to direct inclusion of BMP-2 in alginate or control GMPs. The constructs were supplemented with goat multipotent stromal cells (gMSCs and biphasic calcium phosphate to study osteogenic differentiation and bone formation respectively. BMP-2 release kinetics and bioactivity showed continuous release for three weeks coinciding with osteogenicity. Osteogenic differentiation and bone formation of bioprinted GMP containing constructs were investigated after subcutaneous implantation in mice or rats. BMP-2 significantly increased bone formation, which was not influenced by the release timing. We showed that 3D printing of controlled release particles is feasible and that the released BMP-2 directs osteogenic differentiation in vitro and in vivo.

  7. Effect of a Novel Nonviral Gene Delivery of BMP-2 on Bone Healing

    Directory of Open Access Journals (Sweden)

    P. Schwabe

    2012-01-01

    Full Text Available Background. Gene therapeutic drug delivery approaches have been introduced to improve the efficiency of growth factors at the site of interest. This study investigated the efficacy and safety of a new nonviral copolymer-protected gene vector (COPROG for the stimulation of bone healing. Methods. In vitro, rat osteoblasts were transfected with COPROG + luciferase plasmid or COPROG + hBMP-2 plasmid. In vivo, rat tibial fractures were intramedullary stabilized with uncoated versus COPROG+hBMP-2-plasmid-coated titanium K-wires. The tibiae were prepared for biomechanical and histological analyses at days 28 and 42 and for transfection/safety study at days 2, 4, 7, 28, and 42. Results. In vitro results showed luciferase expression until day 21, and hBMP-2-protein was measured from day 2 – day 10. In vivo, the local application of hBMP-2-plasmid showed a significantly higher maximum load after 42 days compared to that in the control. The histomorphometric analysis revealed a significantly less mineralized periosteal callus area in the BMP-2 group compared to the control at day 28. The rt-PCR showed no systemic biodistribution of luciferase RNA. Conclusion. A positive effect on fracture healing by nonviral BMP-2 plasmid application from COPROG-coated implants could be shown in this study; however, the effect of the vector may be improved with higher plasmid concentrations. Transfection showed no biodistribution to distant organs and was considered to be safe.

  8. Functionalization of PCL-3D Electrospun Nanofibrous Scaffolds for Improved BMP2-Induced Bone Formation.

    Science.gov (United States)

    Miszuk, Jacob M; Xu, Tao; Yao, Qingqing; Fang, Fang; Childs, Josh D; Hong, Zhongkui; Tao, Jianning; Fong, Hao; Sun, Hongli

    2018-03-01

    Bone morphogenic protein 2 (BMP2) is a key growth factor for bone regeneration, possessing FDA approval for orthopedic applications. BMP2 is often required in supratherapeutic doses clinically, yielding adverse side effects and substantial treatment costs. Considering the crucial role of materials for BMPs delivery and cell osteogenic differentiation, we devote to engineering an innovative bone-matrix mimicking niche to improve low dose of BMP2-induced bone formation. Our previous work describes a novel technique, named thermally induced nanofiber self-agglomeration (TISA), for generating 3D electrospun nanofibrous (NF) polycaprolactone (PCL) scaffolds. TISA process could readily blend PCL with PLA, leading to increased osteogenic capabilities in vitro , however, these bio-inert synthetic polymers produced limited BMP2-induced bone formation in vivo. We therefore hypothesize that functionalization of NF 3D PCL scaffolds with bone-like hydroxyapatite (HA) and BMP2 signaling activator phenamil will provide a favorable osteogenic niche for bone formation at low doses of BMP2. Compared to PCL-3D scaffolds, PCL/HA-3D scaffolds demonstrated synergistically enhanced osteogenic differentiation capabilities of C2C12 cells with phenamil. Importantly, in vivo studies showed this synergism was able to generate significantly increased new bone in an ectopic mouse model, suggesting PCL/HA-3D scaffolds act as a favorable synthetic extracellular matrix for bone regeneration.

  9. Comparative expression analyses of bone morphogenetic protein 4 (BMP4) expressions in muscles of tilapia and common carp indicate that BMP4 plays a role in the intermuscular bone distribution in a dose-dependent manner.

    Science.gov (United States)

    Su, Shengyan; Dong, Zaijie

    2018-01-01

    Intermuscular bones in fish negatively influence both meet processing and attractiveness to consumers. Tilapia (Oreochromis niloticus) and common carp (Cyprinus carpio) are both major farmed fish species globally, but whereas the former does not possess intermuscular bones, the latter does. Therefore, these two species might present a good model to study the genetic control of distribution of intermuscular bones in fish. Bone morphogenetic protein 4 (BMP4) gene is associated with tissue ossification and bone regeneration in mammals, but in fish its role in ossification remains understudied. To study the relationship between BMP4 and bone distribution in fish, we determined the expression of BMP4 in muscle tissues of common carp and tilapia on transcriptional and translational levels. As the gene has been merely predicted in silico from the genome of common carp, we have cloned and characterized it. The gene (GenBank: HQ446455) contains one intron and two exons, which encode a 400-amino acid protein with high homology to other known BMP4 protein sequences. Phylogenetic analysis showed that common carp clustered within the Cypriniformes clade (zebrafish was the closest ortholog) and tilapia within the Percomorpha clade. Using microCT scanning, we confirmed that intermuscular bones could be observed only in common carp (none in tilapia), but only in dorsal and caudal muscles (none in the ventral muscle). Expression levels of BMP4 in the muscles of common carp were in agreement with this observation both on transcriptional (qPCR) and translational (immunohistochemistry) level: higher in dorsal and caudal muscles, and lower in the ventral muscle. In tilapia, expression of BMP4 gene was also detectable in all three muscles, but expression levels in all three muscles were comparable to the one observed in the ventral muscle of carp, i.e., very low. Therefore, among the six studied muscles, the expression of BMP4 was high only in the two that possess intermuscular bones

  10. Noggin and Wnt3a enable BMP4-dependent differentiation of telencephalic stem cells into GluR-agonist responsive neurons

    DEFF Research Database (Denmark)

    Andersson, Therese; Duckworth, Joshua K; Fritz, Nicolas

    2011-01-01

    levels, that in turn exerted a concentration-dependent inhibition of BMP4-mediated mesenchymal differentiation of NSCs. Instead, BMP4 exposure of NSCs induced neuronal differentiation in mesenchyme-preventing conditions, whereas treatment with recombinant noggin alone did not. Wnt signaling is known...... to be essential for the development of neurons derived from the dorsal telencephalon, and co-stimulation of NSCs with BMP4+Wnt3a resulted in a synergistic effect yielding significantly increased number of mature neurons compared to stimulation with each factor alone. Thus whereas only a subset of BMP4-induced...... neurons derived from telencephalic NSCs, responded to glutamate receptor (GluR) agonists, over 80% of BMP4+Wnt3a-induced neurons responded appropriately to GluR-agonists. Our results increase the understanding of the role for BMP4 in differentiation of telencephalic multipotent progenitors, and reveal...

  11. Synthetic scaffold coating with adeno-associated virus encoding BMP2 to promote endogenous bone repair.

    Science.gov (United States)

    Dupont, Kenneth M; Boerckel, Joel D; Stevens, Hazel Y; Diab, Tamim; Kolambkar, Yash M; Takahata, Masahiko; Schwarz, Edward M; Guldberg, Robert E

    2012-03-01

    Biomaterial scaffolds functionalized to stimulate endogenous repair mechanisms via the incorporation of osteogenic cues offer a potential alternative to bone grafting for the treatment of large bone defects. We first quantified the ability of a self-complementary adeno-associated viral vector encoding bone morphogenetic protein 2 (scAAV2.5-BMP2) to enhance human stem cell osteogenic differentiation in vitro. In two-dimensional culture, scAAV2.5-BMP2-transduced human mesenchymal stem cells (hMSCs) displayed significant increases in BMP2 production and alkaline phosphatase activity compared with controls. hMSCs and human amniotic-fluid-derived stem cells (hAFS cells) seeded on scAAV2.5-BMP2-coated three-dimensional porous polymer Poly(ε-caprolactone) (PCL) scaffolds also displayed significant increases in BMP2 production compared with controls during 12 weeks of culture, although only hMSC-seeded scaffolds displayed significantly increased mineral formation. PCL scaffolds coated with scAAV2.5-BMP2 were implanted into critically sized immunocompromised rat femoral defects, both with or without pre-seeding of hMSCs, representing ex vivo and in vivo gene therapy treatments, respectively. After 12 weeks, defects treated with acellular scAAV2.5-BMP2-coated scaffolds displayed increased bony bridging and had significantly higher bone ingrowth and mechanical properties compared with controls, whereas defects treated with scAAV2.5-BMP2 scaffolds pre-seeded with hMSCs failed to display significant differences relative to controls. When pooled, defect treatment with scAAV2.5-BMP2-coated scaffolds, both with or without inclusion of pre-seeded hMSCs, led to significant increases in defect mineral formation at all time points and increased mechanical properties compared with controls. This study thus presents a novel acellular bone-graft-free endogenous repair therapy for orthotopic tissue-engineered bone regeneration.

  12. Regulatory role of melatonin and BMP-4 in prolactin production by rat pituitary lactotrope GH3 cells.

    Science.gov (United States)

    Ogura-Ochi, Kanako; Fujisawa, Satoshi; Iwata, Nahoko; Komatsubara, Motoshi; Nishiyama, Yuki; Tsukamoto-Yamauchi, Naoko; Inagaki, Kenichi; Wada, Jun; Otsuka, Fumio

    2017-08-01

    The effects of melatonin on prolactin production and its regulatory mechanism remain uncertain. We investigated the regulatory role of melatonin in prolactin production using rat pituitary lactotrope GH3 cells by focusing on the bone morphogenetic protein (BMP) system. Melatonin receptor activation, induced by melatonin and its receptor agonist ramelteon, significantly suppressed basal and forskolin-induced prolactin secretion and prolactin mRNA expression in GH3 cells. The melatonin MT2 receptor was predominantly expressed in GH3 cells, and the inhibitory effects of melatonin on prolactin production were reversed by treatment with the receptor antagonist luzindole, suggesting functional involvement of MT2 action in the suppression of prolactin release. Melatonin receptor activation also suppressed BMP-4-induced prolactin expression by inhibiting phosphorylation of Smad and transcription of the BMP-target gene Id-1, while BMP-4 treatment upregulated MT2 expression. Melatonin receptor activation suppressed basal, BMP-4-induced and forskolin-induced cAMP synthesis; however, BtcAMP-induced prolactin mRNA expression was not affected by melatonin or ramelteon, suggesting that MT2 activation leads to inhibition of prolactin production through the suppression of Smad signaling and cAMP synthesis. Experiments using intracellular signal inhibitors revealed that the ERK pathway is, at least in part, involved in prolactin induction by GH3 cells. Thus, a new regulatory role of melatonin involving BMP-4 in prolactin secretion was uncovered in lactotrope GH3 cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. BMP2 induces PANC-1 cell invasion by MMP-2 overexpression through ROS and ERK.

    Science.gov (United States)

    Liu, Jun; Ben, Qi-Wen; Yao, Wei-Yan; Zhang, Jian-Jun; Chen, Da-Fan; He, Xiang-Yi; Li, Lei; Yuan, Yao-Zong

    2012-06-01

    The emerging roles of bone morphogenetic proteins (BMPs) in the initiation and progression of multiple cancers have drawn great attention in cancer research. We hypothesized that BMP2 promotes cancer metastasis by modulating MMP-2 secretion and activity through intracellular ROS regulation and ERK activation in human pancreatic cancer. Our data show that stimulation of PANC-1 cells with BMP2 induced MMP-2 secretion and activation, associated with decreased E-cadherin expression, resulting in epithelial-to-mesenchymal transformation (EMT) and cell invasion. Blockade of ROS by the ROS scavenger, 2-MPG, abolished cell invasion, inhibited the EMT process and decreased MMP-2 expression, suggesting ROS accumulation caused an increase in MMP-2 expression in BMP2-stimulated PANC-1 cell invasion. Furthermore, treatment of PANC-1 cells with 2-MPG or ERK inhibitor PD98059 reduced the phosphorylation of ERK, resulting in attenuation of BMP2-induced cell invasion and MMP-2 activation. Taken together, these results suggest that BMP2 induces the cell invasion of PANC-1 cells by enhancing MMP-2 secretion and acting through ROS accumulation and ERK activation.

  14. Gata4 expression in lateral mesoderm is downstream of BMP4 and isactivated directly by Forkhead and GATA transcription factors through adistal enhancer element

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Anabel; De Val, Sarah; Heidt, Analeah B.; Xu, Shan-Mei; Bristow, James; Black, Brian L.

    2005-05-20

    The GATA family of zinc-finger transcription factors plays key roles in the specification and differentiation of multiple cell types during development. GATA4 is an early regulator of gene expression during the development of endoderm and mesoderm, and genetic studies in mice have demonstrated that GATA4 is required for embryonic development.Despite the importance of GATA4 in tissue specification and differentiation, the mechanisms by which Gata4 expression is activated and the transcription factor pathways upstream of GATA4 remain largely undefined. To identify transcriptional regulators of Gata4 in the mouse,we screened conserved noncoding sequences from the mouse Gata4 gene for enhancer activity in transgenic embryos. Here, we define the regulation of a distal enhancer element from Gata4 that is sufficient to direct expression throughout the lateral mesoderm, beginning at 7.5 days of mouse embryonic development. The activity of this enhancer is initially broad but eventually becomes restricted to the mesenchyme surrounding the liver. We demonstrate that the function of this enhancer in transgenic embryos is dependent upon highly conserved Forkhead and GATA transcription factor binding sites, which are bound by FOXF1 and GATA4,respectively. Furthermore, the activity of the Gata4 lateral mesoderm enhancer is attenuated by the BMP antagonist Noggin, and the enhancer is not activated in Bmp4-null embryos. Thus, these studies establish that Gata4 is a direct transcriptional target of Forkhead and GATA transcription factors in the lateral mesoderm, and demonstrate that Gata4lateral mesoderm enhancer activation requires BMP4, supporting a model in which GATA4 serves as a downstream effector of BMP signaling in the lateral mesoderm.

  15. Bone Morphogenic Protein-2 (rhBMP2)-Loaded Silk Fibroin Scaffolds to Enhance the Osteoinductivity in Bone Tissue Engineering

    Science.gov (United States)

    Du, Guang-Yu; He, Sheng-Wei; Sun, Chuan-Xiu; Mi, Li-Dong

    2017-10-01

    There is an increasing demand for formulations of silk fibroin (SF) scaffolds in biomedical applications. SF was crosslinked via glutaraldehyde with osteoinductive recombinant human bone morphogenic protein-2 (rhBMP2) of different ratios viz. (i) 3% SF with no rhBMP2 (SF), (ii) 3% SF with equal amount of rhBMP2 (SF+BMP2), and (iii) 12% SF with 3% of rhBMP2 (4SF+BMP2), and these solutions were used in electrospinning-based fabrication of nanoscaffolds for evaluating increased osteoinductive potential of SF scaffolds with rhBMP2. Stress-strain relationship suggested there is no loss in mechanical strength of fibers with addition of rhBMP2, and mechanical strength of scaffold was improved with increase in concentration of SF. rhBMP2 association increased the water retention capacity of scaffold as evident from swelling studies. Viability of hMSCs was found to be higher in conjugated scaffolds, and scaffolds do not exhibit any cytotoxicity towards guest cells. Cells were found to have higher alkaline phosphatase activity in conjugated scaffolds under in vitro and in vivo conditions which establishes the increased osteoinductivity of the novel construct. The scaffolds were found to be effective for in vivo bone formation as well.

  16. Bmp2 in osteoblasts of periosteum and trabecular bone links bone formation to vascularization and mesenchymal stem cells

    Science.gov (United States)

    Yang, Wuchen; Guo, Dayong; Harris, Marie A.; Cui, Yong; Gluhak-Heinrich, Jelica; Wu, Junjie; Chen, Xiao-Dong; Skinner, Charles; Nyman, Jeffry S.; Edwards, James R.; Mundy, Gregory R.; Lichtler, Alex; Kream, Barbara E.; Rowe, David W.; Kalajzic, Ivo; David, Val; Quarles, Darryl L.; Villareal, Demetri; Scott, Greg; Ray, Manas; Liu, S.; Martin, James F.; Mishina, Yuji; Harris, Stephen E.

    2013-01-01

    Summary We generated a new Bmp2 conditional-knockout allele without a neo cassette that removes the Bmp2 gene from osteoblasts (Bmp2-cKOob) using the 3.6Col1a1-Cre transgenic model. Bones of Bmp2-cKOob mice are thinner, with increased brittleness. Osteoblast activity is reduced as reflected in a reduced bone formation rate and failure to differentiate to a mature mineralizing stage. Bmp2 in osteoblasts also indirectly controls angiogenesis in the periosteum and bone marrow. VegfA production is reduced in Bmp2-cKOob osteoblasts. Deletion of Bmp2 in osteoblasts also leads to defective mesenchymal stem cells (MSCs), which correlates with the reduced microvascular bed in the periosteum and trabecular bones. Expression of several MSC marker genes (α-SMA, CD146 and Angiopoietin-1) in vivo, in vitro CFU assays and deletion of Bmp2 in vitro in α-SMA+ MSCs support our conclusions. Critical roles of Bmp2 in osteoblasts and MSCs are a vital link between bone formation, vascularization and mesenchymal stem cells. PMID:23843612

  17. Expression of BMP-2 in Vascular Endothelial Cells of Recipient May Predict Delayed Graft Function After Renal Transplantation.

    Science.gov (United States)

    Basic-Jukic, Nikolina; Gulin, Marijana; Hudolin, Tvrtko; Kastelan, Zeljko; Katalinic, Lea; Coric, Marijana; Veda, Marija Varnai; Ivkovic, Vanja; Kes, Petar; Jelakovic, Bojan

    2016-01-01

    Delayed graft function (DGF) is associated with adverse outcomes after renal transplantation. Bone morphogenetic protein-2 (BMP-2) is involved in both endothelial function and immunological events. We compared expression of BMP-2 in epigastric artery of renal transplant recipients with immediate graft function (IGF) and DGF. 79 patients were included in this prospective study. Patients were divided in IGF group (64 patients) and DGF group (15 patients). BMP-2 expression in intima media (BMP2m) and endothelium (BMP2e) of epigastric artery was assessed by immunohistochemistry. Lower intensity of BMP2e staining was recorded in DGF compared to IGF. In DGF patients, 93% had no expression of BMP2e and 7% had 1st grade expression, compared to 45% and 41% in IGF group, respectively (P=0.001) (P<0.001 for no expression and P = 0.015 for 1st grade expression). Patients who had BMP2e staining positive had lower odds for DGF (OR 0.059 [0.007, 0.477]) and this remained significant even after adjustment for donor and recipient variables, cold ischemia time, and immunological matching (OR 0.038 [0.003, 0.492]). Our results demonstrate that BMP-2 expression in endothelial cells of epigastric arteries may predict development of DGF. © 2016 The Author(s) Published by S. Karger AG, Basel.

  18. Expression of BMP-2 in Vascular Endothelial Cells of Recipient May Predict Delayed Graft Function After Renal Transplantation

    Directory of Open Access Journals (Sweden)

    Nikolina Basic-Jukic

    2016-11-01

    Full Text Available Background/Aims: Delayed graft function (DGF is associated with adverse outcomes after renal transplantation. Bone morphogenetic protein-2 (BMP-2 is involved in both endothelial function and immunological events. We compared expression of BMP-2 in epigastric artery of renal transplant recipients with immediate graft function (IGF and DGF. Methods: 79 patients were included in this prospective study. Patients were divided in IGF group (64 patients and DGF group (15 patients. BMP-2 expression in intima media (BMP2m and endothelium (BMP2e of epigastric artery was assessed by immunohistochemistry. Results: Lower intensity of BMP2e staining was recorded in DGF compared to IGF. In DGF patients, 93% had no expression of BMP2e and 7% had 1st grade expression, compared to 45% and 41% in IGF group, respectively (P=0.001 (Pst grade expression. Patients who had BMP2e staining positive had lower odds for DGF (OR 0.059 [0.007, 0.477] and this remained significant even after adjustment for donor and recipient variables, cold ischemia time, and immunological matching (OR 0.038 [0.003, 0.492]. Conclusions: Our results demonstrate that BMP-2 expression in endothelial cells of epigastric arteries may predict development of DGF.

  19. rhBMP-2 for posterolateral instrumented lumbar fusion: a multicenter prospective randomized controlled trial.

    Science.gov (United States)

    Hurlbert, R John; Alexander, David; Bailey, Stewart; Mahood, James; Abraham, Ed; McBroom, Robert; Jodoin, Alain; Fisher, Charles

    2013-12-01

    Multicenter randomized controlled trial. To evaluate the effect of recombinant human bone morphogenetic protein (rhBMP-2) on radiographical fusion rate and clinical outcome for surgical lumbar arthrodesis compared with iliac crest autograft. In many types of spinal surgery, radiographical fusion is a primary outcome equally important to clinical improvement, ensuring long-term stability and axial support. Biologic induction of bone growth has become a commonly used adjunct in obtaining this objective. We undertook this study to objectify the efficacy of rhBMP-2 compared with traditional iliac crest autograft in instrumented posterolateral lumbar fusion. Patients undergoing 1- or 2-level instrumented posterolateral lumbar fusion were randomized to receive either autograft or rhBMP-2 for their fusion construct. Clinical and radiographical outcome measures were followed for 2 to 4 years postoperatively. One hundred ninety seven patients were successfully randomized among the 8 participating institutions. Adverse events attributable to the study drug were not significantly different compared with controls. However, the control group experienced significantly more graft-site complications as might be expected. 36-Item Short Form Health Survey, Oswestry Disability Index, and leg/back pain scores were comparable between the 2 groups. After 4 years of follow-up, radiographical fusion rates remained significantly higher in patients treated with rhBMP-2 (94%) than those who received autograft (69%) (P = 0.007). The use of rhBMP-2 for instrumented posterolateral lumbar surgery significantly improves the chances of radiographical fusion compared with the use of autograft. However, there is no associated improvement in clinical outcome within a 4-year follow-up period. These results suggest that use of rhBMP-2 should be considered in cases where lumbar arthrodesis is of primary concern.

  20. Dkk1 haploinsufficiency requires expression of Bmp2 for bone anabolic activity

    Science.gov (United States)

    Intini, Giuseppe; Nyman, Jeffry S.

    2015-01-01

    Bone fractures remain a serious health burden and prevention and enhanced healing of fractures has been obtained by augmenting either BMP or Wnt signaling. However, whether BMP and Wnt signaling are both required or are self-sufficient for anabolic and fracture healing activities has never been fully elucidated. Mice haploinsufficient for Dkk1 (Dkk1+/−) exhibit a high bone mass phenotype due to an up-regulation of canonical Wnt signaling while mice lacking Bmp2 expression in the limbs (Bmp2c/c;Prx1::cre) succumb to spontaneous fracture and are unable to initiate fracture healing; combined, these mice offer an opportunity to examine the requirement for activated BMP signaling on the anabolic and fracture healing activity of Wnts. When Dkk1+/− mice were crossed with Bmp2c/c;Prx1::cre mice, the offspring bearing both genetic alterations were unable to increase bone mass and heal fractures, indicating that increased canonical Wnt signaling is unable to exploit its activity in absence of Bmp2. Thus, our data suggest that BMP signaling is required for Wnt-mediated anabolic activity and that therapies aimed at preventing fractures and fostering fracture repair may need to target both pathways for maximal efficacy. PMID:25603465

  1. BMP2 and BMP7 play antagonistic roles in feather induction

    Science.gov (United States)

    Michon, Frédéric; Forest, Loïc; Collomb, Elodie; Demongeot, Jacques; Dhouailly, Danielle

    2008-01-01

    Summary During embryonic development, feathers first appear as primordia consisting of an epidermal placode associated with a dermal condensation. In most previous studies, the BMPs have been proposed to function as inhibitors of the formation of cutaneous appendages. We showed that the function of BMPs is quite nuanced: BMP-2 and BMP-7, which are expressed in both skin components, act antagonistically and yet are both involved in the dermal condensations formation. BMP-7, the first to be expressed, is implicated in chemotaxis which leads to cell recruitment to the condensation, whereas BMP-2, which is expressed later, leads to an arrest of cell migration, likely via its modulation of EIIIA Fibronectin domain and α4-Integrin expression. We also propose a mathematical model, a reaction-diffusion system, based on cell proliferation, chemotaxis and the timing of BMP-2 and BMP-7 expression, which simulates the endogenous situation and reproduces the negative effects of excess BMP-2 or BMP-7 on feather patterning. PMID:18635609

  2. Enhanced osteogenesis of adipose derived stem cells with Noggin suppression and delivery of BMP-2.

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    Jiabing Fan

    Full Text Available Bone morphogenetic proteins (BMPs are believed to be the most potent osteoinductive factors. However, BMPs are highly pleiotropic molecules and their supra-physiological high dose requirement leads to adverse side effects and inefficient bone formation. Thus, there is a need to develop alternative osteoinductive growth factor strategies that can effectively complement BMP activity. In this study, we intrinsically stimulated BMP signaling in adipose derived stem cells (ASCs by downregulating noggin, a potent BMP antagonist, using an RNAi strategy. ASCs transduced with noggin shRNA significantly enhanced osteogenic differentiation of cells. The potency of endogenous BMPs was subsequently enhanced by stimulating ASCs with exogenous BMPs at a significantly reduced dose. The level of mineralization in noggin shRNA treated ASCs when treated with BMP-2 was comparable to that of control shRNA treated cell treated with 10-fold more BMP-2. The complementary strategy of noggin suppression + BMP-2 to enhance osteogenesis was further confirmed in 3D in vitro environments using scaffolds consisting of chitosan (CH, chondroitin sulfate (CS, and apatite layer on their surfaces designed to slowly release BMP-2. This finding supports the novel therapeutic potential of this complementary strategy in bone regeneration.

  3. Bone marrow concentrate promotes bone regeneration with a suboptimal-dose of rhBMP-2.

    Science.gov (United States)

    Egashira, Kazuhiro; Sumita, Yoshinori; Zhong, Weijian; I, Takashi; Ohba, Seigo; Nagai, Kazuhiro; Asahina, Izumi

    2018-01-01

    Bone marrow concentrate (BMC), which is enriched in mononuclear cells (MNCs) and platelets, has recently attracted the attention of clinicians as a new optional means for bone engineering. We previously reported that the osteoinductive effect of bone morphogenetic protein-2 (BMP-2) could be enhanced synergistically by co-transplantation of peripheral blood (PB)-derived platelet-rich plasma (PRP). This study aims to investigate whether BMC can effectively promote bone formation induced by low-dose BMP-2, thereby reducing the undesirable side-effects of BMP-2, compared to PRP. Human BMC was obtained from bone marrow aspirates using an automated blood separator. The BMC was then seeded onto β-TCP granules pre-adsorbed with a suboptimal-dose (minimum concentration to induce bone formation at 2 weeks in mice) of recombinant human (rh) BMP-2. These specimens were transplanted subcutaneously to the dorsal skin of immunodeficient-mice and the induction of ectopic bone formation was assessed 2 and 4 weeks post-transplantation. Transplantations of five other groups [PB, PRP, platelet-poor plasma (PPP), bone marrow aspirate (BM), and BM-PPP] were employed as experimental controls. Then, to clarify the effects on vertical bone augmentation, specimens from the six groups were transplanted for on-lay placement on the craniums of mice. The results indicated that BMC, which contained an approximately 2.5-fold increase in the number of MNCs compared to PRP, could accelerate ectopic bone formation until 2 weeks post-transplantation. On the cranium, the BMC group promoted bone augmentation with a suboptimal-dose of rhBMP-2 compared to other groups. Particularly in the BMC specimens harvested at 4 weeks, we observed newly formed bone surrounding the TCP granules at sites far from the calvarial bone. In conclusion, the addition of BMC could reduce the amount of rhBMP-2 by one-half via its synergistic effect on early-phase osteoinduction. We propose here that BMC transplantation

  4. Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells

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    Grassi Rici Rose

    2012-02-01

    Full Text Available Abstract Background The bone morphogenetic proteins (BMPs belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. Results We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p

  5. Mesenchymal stem cells with rhBMP-2 inhibits the growth of canine osteosarcoma cells.

    Science.gov (United States)

    Rici, Rose Eli Grassi; Alcântara, Dayane; Fratini, Paula; Wenceslau, Cristiane Valverde; Ambrósio, Carlos Eduardo; Miglino, Maria Angelica; Maria, Durvanei Augusto

    2012-02-22

    The bone morphogenetic proteins (BMPs) belong to a unique group of proteins that includes the growth factor TGF-β. BMPs play important roles in cell differentiation, cell proliferation, and inhibition of cell growth. They also participate in the maturation of several cell types, depending on the microenvironment and interactions with other regulatory factors. Depending on their concentration gradient, the BMPs can attract various types of cells and act as chemotactic, mitogenic, or differentiation agents. BMPs can interfere with cell proliferation and the formation of cartilage and bone. In addition, BMPs can induce the differentiation of mesenchymal progenitor cells into various cell types, including chondroblasts and osteoblasts. The aim of this study was to analyze the effects of treatment with rhBMP-2 on the proliferation of canine mesenchymal stem cells (cMSCs) and the tumor suppression properties of rhBMP-2 in canine osteocarcoma (OST) cells. Osteosarcoma cell lines were isolated from biopsies and excisions of animals with osteosarcoma and were characterized by the Laboratory of Biochemistry and Biophysics, Butantan Institute. The mesenchymal stem cells were derived from the bone marrow of canine fetuses (cMSCs) and belong to the University of São Paulo, College of Veterinary Medicine (FMVZ-USP) stem cell bank. After expansion, the cells were cultured in a 12-well Transwell system; cells were treated with bone marrow mesenchymal stem cells associated with rhBMP2. Expression of the intracytoplasmic and nuclear markers such as Caspase-3, Bax, Bad, Bcl-2, Ki-67, p53, Oct3/4, Nanog, Stro-1 were performed by flow citometry. We evaluated the regenerative potential of in vitro treatment with rhBMP-2 and found that both osteogenic induction and tumor regression occur in stem cells from canine bone marrow. rhBMP-2 inhibits the proliferation capacity of OST cells by mechanisms of apoptosis and tumor suppression mediated by p53. We propose that rhBMP-2 has great

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

    Science.gov (United States)

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

    2017-07-01

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

  7. Bone morphogenetic protein 2 (BMP2) induces growth suppression and enhances chemosensitivity of human colon cancer cells

    DEFF Research Database (Denmark)

    Vishnubalaji, Radhakrishnan; Yue, Shijun; Alfayez, Musaad

    2016-01-01

    expression were assessed using qRT-PCR. AlamarBlue assay was used to assess cell viability in vitro. In vivo experiments were conducted using SCID mice. RESULTS: Our data revealed frequent downregulation of BMP2 in primary CRC tissues. Additionally, interrogation of publically available gene expression......, suggesting that restoration of BMP2 expression could be a potential therapeutic strategy for CRC....

  8. Deficiency of retinaldehyde dehydrogenase 1 induces BMP2 and increases bone mass in vivo.

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    Shriram Nallamshetty

    Full Text Available The effects of retinoids, the structural derivatives of vitamin A (retinol, on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA and its precursor all trans retinaldehyde (Rald, exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1, the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT demonstrated that Aldh1a1-deficient (Aldh1a1(-/- female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1(-/- mice. In serum assays, Aldh1a1(-/- mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1(-/- mesenchymal stem cells (MSCs expressed significantly higher levels of bone morphogenetic protein 2 (BMP2 and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1(-/- mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1(-/- mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling.

  9. Deficiency of retinaldehyde dehydrogenase 1 induces BMP2 and increases bone mass in vivo.

    Science.gov (United States)

    Nallamshetty, Shriram; Wang, Hong; Rhee, Eun-Jung; Kiefer, Florian W; Brown, Jonathan D; Lotinun, Sutada; Le, Phuong; Baron, Roland; Rosen, Clifford J; Plutzky, Jorge

    2013-01-01

    The effects of retinoids, the structural derivatives of vitamin A (retinol), on post-natal peak bone density acquisition and skeletal remodeling are complex and compartment specific. Emerging data indicates that retinoids, such as all trans retinoic acid (ATRA) and its precursor all trans retinaldehyde (Rald), exhibit distinct and divergent transcriptional effects in metabolism. Despite these observations, the role of enzymes that control retinoid metabolism in bone remains undefined. In this study, we examined the skeletal phenotype of mice deficient in retinaldehyde dehydrogenase 1 (Aldh1a1), the enzyme responsible for converting Rald to ATRA in adult animals. Bone densitometry and micro-computed tomography (µCT) demonstrated that Aldh1a1-deficient (Aldh1a1(-/-) ) female mice had higher trabecular and cortical bone mass compared to age and sex-matched control C57Bl/6 wild type (WT) mice at multiple time points. Histomorphometry confirmed increased cortical bone thickness and demonstrated significantly higher bone marrow adiposity in Aldh1a1(-/-) mice. In serum assays, Aldh1a1(-/-) mice also had higher serum IGF-1 levels. In vitro, primary Aldh1a1(-/-) mesenchymal stem cells (MSCs) expressed significantly higher levels of bone morphogenetic protein 2 (BMP2) and demonstrated enhanced osteoblastogenesis and adipogenesis versus WT MSCs. BMP2 was also expressed at higher levels in the femurs and tibias of Aldh1a1(-/-) mice with accompanying induction of BMP2-regulated responses, including expression of Runx2 and alkaline phosphatase, and Smad phosphorylation. In vitro, Rald, which accumulates in Aldh1a1(-/-) mice, potently induced BMP2 in WT MSCs in a retinoic acid receptor (RAR)-dependent manner, suggesting that Rald is involved in the BMP2 increases seen in Aldh1a1 deficiency in vivo. Collectively, these data implicate Aldh1a1 as a novel determinant of cortical bone density and marrow adiposity in the skeleton in vivo through modulation of BMP signaling.

  10. Morphogen and community effects determine cell fates in response to BMP4 signaling in human embryonic stem cells.

    Science.gov (United States)

    Nemashkalo, Anastasiia; Ruzo, Albert; Heemskerk, Idse; Warmflash, Aryeh

    2017-09-01

    Paracrine signals maintain developmental states and create cell fate patterns in vivo and influence differentiation outcomes in human embryonic stem cells (hESCs) in vitro Systematic investigation of morphogen signaling is hampered by the difficulty of disentangling endogenous signaling from experimentally applied ligands. Here, we grow hESCs in micropatterned colonies of 1-8 cells ('µColonies') to quantitatively investigate paracrine signaling and the response to external stimuli. We examine BMP4-mediated differentiation in µColonies and standard culture conditions and find that in µColonies, above a threshold concentration, BMP4 gives rise to only a single cell fate, contrary to its role as a morphogen in other developmental systems. Under standard culture conditions BMP4 acts as a morphogen but this requires secondary signals and particular cell densities. We find that a 'community effect' enforces a common fate within µColonies, both in the state of pluripotency and when cells are differentiated, and that this effect allows a more precise response to external signals. Using live cell imaging to correlate signaling histories with cell fates, we demonstrate that interactions between neighbors result in sustained, homogenous signaling necessary for differentiation. © 2017. Published by The Company of Biologists Ltd.

  11. NOX4 mediates BMP4-induced upregulation of TRPC1 and 6 protein expressions in distal pulmonary arterial smooth muscle cells.

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    Qian Jiang

    Full Text Available Our previous studies demonstrated that bone morphogenetic protein 4 (BMP4 mediated, elevated expression of canonical transient receptor potential (TRPC largely accounts for the enhanced proliferation in pulmonary arterial smooth muscle cells (PASMCs. In the present study, we sought to determine the signaling pathway through which BMP4 up-regulates TRPC expression.We employed recombinant human BMP4 (rhBMP4 to determine the effects of BMP4 on NADPH oxidase 4 (NOX4 and reactive oxygen species (ROS production in rat distal PASMCs. We also designed small interfering RNA targeting NOX4 (siNOX4 and detected whether NOX4 knockdown affects rhBMP4-induced ROS, TRPC1 and 6 expression, cell proliferation and intracellular Ca2+ determination in PASMCs.In rhBMP4 treated rat distal PASMCs, NOX4 expression was (226.73±11.13 %, and the mean ROS level was (123.65±1.62 % of that in untreated control cell. siNOX4 transfection significantly reduced rhBMP4-induced elevation of the mean ROS level in PASMCs. Moreover, siNOX4 transfection markedly reduced rhBMP4-induced elevation of TRPC1 and 6 proteins, basal [Ca2+]i and SOCE. Furthermore, compared with control group (0.21±0.001, the proliferation of rhBMP4 treated cells was significantly enhanced (0.41±0.001 (P<0.01. However, such increase was attenuated by knockdown of NOX4. Moreover, external ROS (H2O2 100 µM, 24 h rescued the effects of NOX4 knockdown, which included the declining of TRPC1 and 6 expression, basal intracellular calcium concentration ([Ca2+]i and store-operated calcium entry (SOCE, suggesting that NOX4 plays as an important mediator in BMP4-induced proliferation and intracellular calcium homeostasis.These results suggest that BMP4 may increase ROS level, enhance TRPC1 and 6 expression and proliferation by up-regulating NOX4 expression in PASMCs.

  12. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Chieri [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Iwasaki, Tsuyoshi, E-mail: tsuyo-i@huhs.ac.jp [Division of Pharmacotherapy, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe 650-8530 (Japan); Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer We investigated the role of S1P signaling for osteoblast differentiation. Black-Right-Pointing-Pointer Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. Black-Right-Pointing-Pointer S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. Black-Right-Pointing-Pointer MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P

  13. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    International Nuclear Information System (INIS)

    Sato, Chieri; Iwasaki, Tsuyoshi; Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime

    2012-01-01

    Highlights: ► We investigated the role of S1P signaling for osteoblast differentiation. ► Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. ► S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. ► MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P receptor-mediated signaling plays a crucial role for osteoblast differentiation.

  14. rhBMP-2 (ACS and CRM formulations) overcomes pseudarthrosis in a New Zealand white rabbit posterolateral fusion model.

    Science.gov (United States)

    Lawrence, James P; Waked, Walid; Gillon, Thomas J; White, Andrew P; Spock, Christopher R; Biswas, Debdut; Rosenberger, Patricia; Troiano, Nancy; Albert, Todd J; Grauer, Jonathan N

    2007-05-15

    The study design consisted of a New Zealand white rabbit model of pseudarthrosis repair. Study groups consisting of no graft, autograft, or recombinant human bone morphogenetic protein-2 (rhBMP-2) with absorbable collagen sponge (ACS) or compression resistant matrix (CRM) were evaluated. To evaluate the relative efficacy of bone graft materials (autograft, ACS, and CRM). rhBMP-2 has been shown to have a 100% fusion rate in a primary rabbit fusion model, even in the presence of nicotine, which is known to inhibit fusion. Seventy-two New Zealand white rabbits underwent posterolateral lumbar fusion with iliac crest autograft. To establish pseudarthroses, nicotine was administered to all animals. At 5 weeks, the spines were explored and all pseudarthroses were redecorticated and implanted with no graft, autograft, rhBMP-2/ACS, or rhBMP-2/CRM. At 10 weeks, fusions were assessed by manual palpation and histology. Eight rabbits (11%) were lost to complications. At 5 weeks, 66 (97%) had pseudarthroses. At 10 weeks, attempted pseudarthrosis repairs were fused in 1 of 16 of no graft rabbits (6%), 5 of 17 autograft rabbits (29%), and 31 of 31 rhBMP-2 rabbits (with ACS or CRM) (100%). Histologic analysis demonstrated more mature bone formation in the rhBMP-2 groups. The 2 rhBMP-2 formulations led to significantly higher fusion rates and histologic bone formation than no graft and autograft controls in this pseudarthrosis repair model.

  15. Involvement of over-expressed BMP4 in pentylenetetrazol kindling-induced cell proliferation in the dentate gyrus of adult rats

    International Nuclear Information System (INIS)

    Yin Jinbo; Ma Yuxin; Yin Qing; Xu Haiwei; An Ning; Liu Shiyong; Fan Xiaotang; Yang Hui

    2007-01-01

    The dentate gyrus (DG) of the hippocampus is one of a few regions in the adult mammalian brain characterized by ongoing neurogenesis. Proliferation of neural precursors in the granule cell layer of the DG has been identified in pentylenetetrazol (PTZ) kindling epilepsy model, however, little is known about the molecular mechanism. We previously reported that the expression pattern of bone morphogenetic proteins-4 (BMP4) mRNA in the hippocampus was developmentally regulated and mainly localized in the DG of the adult. To explore the role of BMP4 in epileptic activity, we detected BMP4 expression in the DG during PTZ kindling process and explore its correlation with cell proliferation combined with bromodeoxyuridine (BrdU) labeling technique. We found that dynamic changes in BMP4 level and BrdU labeled cells dependent on the kindling stage of PTZ induced seizure-prone state. The number of BMP4 mRNA-positive cells and BrdU labeled cells reached the top level 1 day after PTZ kindled, then declined to base level 2 months later. Furthermore, there was a significant correlation between increased BMP4 mRNA expression and increased number of BrdU labeled cells. After effectively blocked expression of BMP4 with antisense oligodeoxynucleotides(ASODN), the BrdU labeled cells in the dentate gyrus subgranular zone(DG-SGZ) and hilus were significantly decreased 16d after First PTZ injection and 1, 3, 7, 14d after kindled respectively. These findings suggest that increased proliferation in the DG of the hippocampus resulted from kindling epilepsy elicited by PTZ maybe be modulated by BMP4 over-expression

  16. Electrospun PLLA nanofiber scaffolds and their use in combination with BMP-2 for reconstruction of bone defects.

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    Markus D Schofer

    Full Text Available Adequate migration and differentiation of mesenchymal stem cells is essential for regeneration of large bone defects. To achieve this, modern graft materials are becoming increasingly important. Among them, electrospun nanofiber scaffolds are a promising approach, because of their high physical porosity and potential to mimic the extracellular matrix (ECM.The objective of the present study was to examine the impact of electrospun PLLA nanofiber scaffolds on bone formation in vivo, using a critical size rat calvarial defect model. In addition we analyzed whether direct incorporation of bone morphogenetic protein 2 (BMP-2 into nanofibers could enhance the osteoinductivity of the scaffolds. Two critical size calvarial defects (5 mm were created in the parietal bones of adult male Sprague-Dawley rats. Defects were either (1 left unfilled, or treated with (2 bovine spongiosa, (3 PLLA scaffolds alone or (4 PLLA/BMP-2 scaffolds. Cranial CT-scans were taken at fixed intervals in vivo. Specimens obtained after euthanasia were processed for histology, histomorphometry and immunostaining (Osteocalcin, BMP-2 and Smad5.PLLA scaffolds were well colonized with cells after implantation, but only showed marginal ossification. PLLA/BMP-2 scaffolds showed much better bone regeneration and several ossification foci were observed throughout the defect. PLLA/BMP-2 scaffolds also stimulated significantly faster bone regeneration during the first eight weeks compared to bovine spongiosa. However, no significant differences between these two scaffolds could be observed after twelve weeks. Expression of osteogenic marker proteins in PLLA/BMP-2 scaffolds continuously increased throughout the observation period. After twelve weeks osteocalcin, BMP-2 and Smad5 were all significantly higher in the PLLA/BMP-2 group than in all other groups.Electrospun PLLA nanofibers facilitate colonization of bone defects, while their use in combination with BMP-2 also increases bone

  17. Stimulation of porcine bone marrow stromal cells by hyaluronan, dexamethasone and rhBMP-2

    DEFF Research Database (Denmark)

    Zou, Xuenong; Li, Haisheng; Chen, Li

    2004-01-01

    and 7. When BMSc were cultivated with HY of 4.0 mg/ml alone, its combinations with Dex (+) and 10 ng/ml rhBMP-2, and with DMEM/FBS alone, expression of bone-related marker genes was evaluated by real-time reverse transcription-polymerase chain reaction (Real-time RT-PCR) analysis. Osteocalcin was up...... collagen and type X collagen were down-regulated in the presence of 4 mg/ml HY by Day 7. These results suggest that HY stimulates BMSc proliferation, osteocalcin gene expression, and a secretion of enzymes such as that of ALP activity in vitro. More importantly, HY can interact with Dex and rhBMP-2...

  18. Histone deacetylases control neurogenesis in embryonic brain by inhibition of BMP2/4 signaling.

    Directory of Open Access Journals (Sweden)

    Maya Shakèd

    Full Text Available BACKGROUND: Histone-modifying enzymes are essential for a wide variety of cellular processes dependent upon changes in gene expression. Histone deacetylases (HDACs lead to the compaction of chromatin and subsequent silencing of gene transcription, and they have recently been implicated in a diversity of functions and dysfunctions in the postnatal and adult brain including ocular dominance plasticity, memory consolidation, drug addiction, and depression. Here we investigate the role of HDACs in the generation of neurons and astrocytes in the embryonic brain. PRINCIPAL FINDINGS: As a variety of HDACs are expressed in differentiating neural progenitor cells, we have taken a pharmacological approach to inhibit multiple family members. Inhibition of class I and II HDACs in developing mouse embryos with trichostatin A resulted in a dramatic reduction in neurogenesis in the ganglionic eminences and a modest increase in neurogenesis in the cortex. An identical effect was observed upon pharmacological inhibition of HDACs in in vitro-differentiating neural precursors derived from the same brain regions. A reduction in neurogenesis in ganglionic eminence-derived neural precursors was accompanied by an increase in the production of immature astrocytes. We show that HDACs control neurogenesis by inhibition of the bone morphogenetic protein BMP2/4 signaling pathway in radial glial cells. HDACs function at the transcriptional level by inhibiting and promoting, respectively, the expression of Bmp2 and Smad7, an intracellular inhibitor of BMP signaling. Inhibition of the BMP2/4 signaling pathway restored normal levels of neurogenesis and astrogliogenesis to both ganglionic eminence- and cortex-derived cultures in which HDACs were inhibited. CONCLUSIONS: Our results demonstrate a transcriptionally-based regulation of BMP2/4 signaling by HDACs both in vivo and in vitro that is critical for neurogenesis in the ganglionic eminences and that modulates cortical

  19. Enhanced Bone Formation in Segmental Defects with BMP2 in a Biologically Relevant Molecular Context

    Science.gov (United States)

    2016-10-16

    interfere with the biological activity of the BMP2, and because radioisotope detection methods are highly sensitive and remain quantitative across a large...PRINCIPAL INVESTIGATOR: Dominik R. Haudenschild CONTRACTING ORGANIZATION: University of California, Davis Davis, CA 95618 REPORT DATE : October 2016...control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE October 2016 2. REPORT TYPE Annual 3. DATES COVERED 30 Sep 2015

  20. Bone regeneration in osteoporosis by delivery BMP-2 and PRGF from tetronic-alginate composite thermogel.

    Science.gov (United States)

    Segredo-Morales, Elisabet; García-García, Patricia; Reyes, Ricardo; Pérez-Herrero, Edgar; Delgado, Araceli; Évora, Carmen

    2018-05-30

    As the life expectancy of the world population increases, osteoporotic (OP) fracture risk increase. Therefore in the present study a novel injectable thermo-responsive hydrogel loaded with microspheres of 17β-estradiol, microspheres of bone morphogenetic protein-2 (BMP-2) and plasma rich in growth factors (PRGF) was applied locally to regenerate a calvaria critical bone defect in OP female rats. Three systems were characterized: Tetronic® 1307 (T-1307) reinforced with alginate (T-A), T-A with PRGF and T-A-PRGF with microspheres. The addition of the microspheres increased the viscosity but the temperature for the maximum viscosity did not change (22-24 °C). The drugs were released during 6 weeks in one fast phase (three days) followed by a long slow phase. In vivo evaluation was made in non-OP and OP rats treated with T-A, T-A with microspheres of 17β-estradiol (T-A-βE), T-A-βE prepared with PRGF (T-A-PRGF-βE), T-A-βE with microspheres of BMP-2 (T-A-βE-BMP-2) and the combination of the three (T-A-PRGF-βE-BMP). After 12 weeks, histological and histomorphometric analyzes showed a synergic effect due to the addition of BMP-2 to the T-A-βE formulation. The PRGF did not increased the bone repair. The new bone filling the OP defect was less mineralized than in the non-OP groups. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. [Preparation of vanilline cross-linked rhBMP-2/chitosan microspheres and its effect on mesenchymal stem cells].

    Science.gov (United States)

    Wu, Gui; Wang, Hai; Qiu, Guixing; Yu, Xin; Su, Xinlin; Ma, Pei; Yin, Bo; Wu, Zhihong

    2015-06-02

    To prepare rhBMP-2/chitosan microspheres (rhBMP-2 CMs) with vanilline as a cross-linking reagent and study the biocompatibility and drug release characteristic of microspheres in vitro. Emulsion cross-linking method was utilized to prepare rhBMP-2 CMs, Scanning electron microscope (SEM) was used to observe the microstructure of microspheres.Leaching solution of microspheres and blank culture medium were designated as experimental and control groups respectively. Both groups were cultured with human mesenchymal stem cells (hMSCs) to determine its cytotoxicity and its effect on the proliferation of hMSCs. Dynamic immersion method was used to examine the in vitro release characteristic of rhBMP-2. And the alkaline phosphatase (ALP) activity of hMSCs was determined to reveal the bioactivity of released rhBMP-2. The rhBMP-2 CMs were spherical under SEM.After treating with leaching solution for 24 and 48 h, there was no inter-group statistical difference in optical density (OD) values at both timepoints (24 h:0.72 ± 0.07 vs 0.73 ± 0.05, P > 0.05; 48 h:1.19 ± 0.11 vs 1.27 ± 0.06, P > 0.05). After culturing with leaching solution for 1, 3 and 7 days, the number of cells increased with time for both groups. And the OD values were not statistically different at each timepoint. Five milligram rhBMP-2 CMs soaked for 19 days with a gradual release of rhBMP-2. The concentration of rhBMP-2 was 216.1 ± 20.0 ng/ml at Day 19. At Days 3 and 7, the ALP activities of hMSCs were (0.50 ± 0.07) and (0.68 ± 0.06) µmol pNPP·min⁻¹·mg⁻¹ protein respectively and both were higher than that of blank culture medium group (0.14 ± 0.01) (P < 0.05). With an excellent biocompatibility, rhBMP-2 CMs may be an ideal carrier for control-released rhBMP-2 and encapsulated rhBMP-2 remains bioactive.

  2. Kaempferol induces chondrogenesis in ATDC5 cells through activation of ERK/BMP-2 signaling pathway.

    Science.gov (United States)

    Nepal, Manoj; Li, Liang; Cho, Hyoung Kwon; Park, Jong Kun; Soh, Yunjo

    2013-12-01

    Endochondral bone formation occurs when mesenchymal cells condense to differentiate into chondrocytes, the primary cell types of cartilage. The aim of the present study was to identify novel factors regulating chondrogenesis. We investigated whether kaempferol induces chondrogenic differentiation in clonal mouse chondrogenic ATDC5 cells. Kaempferol treatment stimulated the accumulation of cartilage nodules in a dose-dependent manner. Kaempferol-treated ATDC5 cells stained more intensely with alcian blue staining than control cells, suggesting greater synthesis of matrix proteoglycans in the kaempferol-treated cells. Similarly, kaempferol induced greater activation of alkaline phosphatase activity than control cells, and it enhanced the expression of chondrogenic marker genes, such as collagen type I, collagen type X, OCN, Runx2, and Sox9. Kaempferol induced an acute activation of extracellular signal-regulated kinase (ERK) but not c-jun N-terminal kinase or p38 MAP kinase. PD98059, an inhibitor of MAPK/ERK, decreased in stained cells treated with kaempferol. Furthermore, kaempferol greatly expressed the protein and mRNA levels of BMP-2, suggesting chondrogenesis was stimulated via a BMP-2 pathway. Taken together, our results suggest that kaempferol has chondromodulating effects via an ERK/BMP-2 signaling pathway and could potentially be used as a therapeutic agent for bone growth disorders. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Expressional and functional analyses of transcription factors activated by BMP-4s signaling in early xenopus embryo; BMP-4 shigunaru dentatsu kiko to sono hyoteki kakunai tensha inshi ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Maeno, Mitsugu [Niigata University, Niigata (Japan). Faculty of Science

    1998-12-16

    The expression and physiological function of two transcription factors, GATA-2 and Xmsx-1, in amphibian embryos has been analyzed. The expression of these mRNAs in embryonic cells were firmly regulated by the BMP-4 signaling, that plays a central role in the formation of ventral tissues. The microinjection studies of GATA-2 RNA into embryonic cells suggested that this factor functions in two adjacent germ layers, mesoderm and ectoderm, to participate in blood cell formation in ventral area of embryo. Embryos injected with Xmsx-1 RNA, but not with GATA-2, in dorsal blastomeres exhibited a ventralized phenotype, with microcephaly and swollen abdomen. Thus, Xmsx-1 is a ventralizing agent. However, on the basis of molecular marker analyses, Xmsx-1 did not promote erythropoietic differentiation, but promoted muscle tissue formation. It has been concluded that Xmsx-1 si a target transcription factor of the BMP-4 signaling, but possesses a distinct activity on dorso-ventral patterning of mesodermal tissues. (author)

  4. Trends Analysis of rhBMP2 Utilization in Single-Level Anterior Lumbar Interbody Fusion in the United States.

    Science.gov (United States)

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

    2018-04-01

    Retrospective case study. To evaluate the trends and demographics of recombinant human bone morphogenetic protein 2 (rhBMP2) utilization in single-level anterior lumbar interbody fusion (ALIF) in the United States. Patients who underwent single-level ALIF from 2005 to 2011 were identified by searching ICD-9 diagnosis and procedure codes in the PearlDiver Patient Records Database (PearlDiver Technologies, Fort Wayne, IN), a national database of orthopedic insurance records. The year of procedure, age, gender, and region of the United States were analyzed for each patient. A total of 921 patients were identified who underwent a single-level ALIF in this study. The average rate of single-level ALIF with rhBMP2 utilization increased (35%-48%) from 2005 to 2009, but sharply decreased to 16.7% in 2010 and 15.0% in 2011. The overall incidence of single-level ALIF without rhBMP2 (0.20 cases per 100 000 patients) was more than twice of the incidence of single-level ALIF with rhBMP2 (0.09 cases per 100 000 patients). The average rate of single-level ALIF with rhBMP2 utilization is highest in West (41.4%), followed by Midwest (33.3%), South (26.5%) and Northeast (22.2%). The highest incidence of single-level ALIF with rhBMP2 was observed in the group aged less than 65 years (compared with any other age groups, P level ALIF increased from 2006 to 2009, but decreased in 2010 and 2011. The Northeast region had the lowest incidence of rhBMP2 utilization. The group aged less than 65 years trended to have the higher incidence of single-level ALIF with rhBMP2 utilization.

  5. Expression characteristics of BMP2, BMPR-IA and Noggin in different stages of hair follicle in yak skin.

    Science.gov (United States)

    Song, Liang-Li; Cui, Yan; Yu, Si-Jiu; Liu, Peng-Gang; Liu, Jun; Yang, Xue; He, Jun-Feng; Zhang, Qian

    2018-05-01

    Bone morphogenetic protein 2 (BMP2), BMP receptor-IA (BMPR-IA), and the BMP2 antagonist Noggin are important proteins involved in regulating the hair follicle (HF) cycle in skin. In order to explore the expression profiles of BMP2, BMPR-IA, and Noggin in the HF cycle of yak skin, we collected adult yak skin in the telogen, proanagen, and midanagen phases of HFs and evaluated gene and protein expression by real-time quantitative polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry. qRT-PCR and western blotting results showed that BMP2 and BMPR-IA expression levels were highest in the telogen of HFs and higher than that of Noggin in the same phase. The expression of Noggin was significantly higher in proanagen and midanagen phases of HFs than in the telogen phase, with the highest expression observed in the proanagen phase. Moreover, the expression of Noggin in the proanagen phase was significantly higher than those of BMP2 and BMPR-IA during the same phase. Immunohistochemistry results showed that BMP2, BMPR-IA, and Noggin were expressed in the skin epidermis, sweat glands, sebaceous glands, HF outer root sheath, and hair matrix. In summary, the characteristic expression profiles of BMP2, BMPR-IA, and Noggin suggested that BMP2 and BMPR-IA had inhibitory effects on the growth of HFs in yaks, whereas Noggin promoted the growth of yak HFs, mainly by affecting skin epithelial cell activity. These results provide a basis for further studies of HF development and cycle transition in yak skin. Copyright © 2017. Published by Elsevier Inc.

  6. Myoblast sensitivity and fibroblast insensitivity to osteogenic conversion by BMP-2 correlates with the expression of Bmpr-1a

    Directory of Open Access Journals (Sweden)

    North Kathryn N

    2009-05-01

    Full Text Available Abstract Background Osteoblasts are considered to primarily arise from osseous progenitors within the periosteum or bone marrow. We have speculated that cells from local soft tissues may also take on an osteogenic phenotype. Myoblasts are known to adopt a bone gene program upon treatment with the osteogenic bone morphogenetic proteins (BMP-2,-4,-6,-7,-9, but their osteogenic capacity relative to other progenitor types is unclear. We further hypothesized that the sensitivity of cells to BMP-2 would correlate with BMP receptor expression. Methods We directly compared the BMP-2 sensitivity of myoblastic murine cell lines and primary cells with osteoprogenitors from osseous tissues and fibroblasts. Fibroblasts forced to undergo myogenic conversion by transduction with a MyoD-expressing lentiviral vector (LV-MyoD were also examined. Outcome measures included alkaline phosphatase expression, matrix mineralization, and expression of osteogenic genes (alkaline phosphatase, osteocalcin and bone morphogenetic protein receptor-1A as measured by quantitative PCR. Results BMP-2 induced a rapid and robust osteogenic response in myoblasts and osteoprogenitors, but not in fibroblasts. Myoblasts and osteoprogenitors grown in osteogenic media rapidly upregulated Bmpr-1a expression. Chronic BMP-2 treatment resulted in peak Bmpr-1a expression at day 6 before declining, suggestive of a negative feedback mechanism. In contrast, fibroblasts expressed low levels of Bmpr-1a that was only weakly up-regulated by BMP-2 treatment. Bioinformatics analysis confirmed the presence of myogenic responsive elements in the proximal promoter region of human and murine BMPR-1A/Bmpr-1a. Forced myogenic gene expression in fibroblasts was associated with a significant increase in Bmpr-1a expression and a synergistic increase in the osteogenic response to BMP-2. Conclusion These data demonstrate the osteogenic sensitivity of muscle progenitors and provide a mechanistic insight into the

  7. Noggin and BMP4 co-modulate adult hippocampal neurogenesis in the APPswe/PS1ΔE9 transgenic mouse model of Alzheimer's disease

    International Nuclear Information System (INIS)

    Tang, Jun; Song, Min; Wang, Yanyan; Fan, Xiaotang; Xu, Haiwei; Bai, Yun

    2009-01-01

    In addition to the subventricular zone, the dentate gyrus of the hippocampus is one of the few brain regions in which neurogenesis continues into adulthood. Perturbation of neurogenesis can alter hippocampal function, and previous studies have shown that neurogenesis is dysregulated in Alzheimer disease (AD) brain. Bone morphogenetic protein-4 (BMP4) and its antagonist Noggin have been shown to play important roles both in embryonic development and in the adult nervous system, and may regulate hippocampal neurogenesis. Previous data indicated that increased expression of BMP4 mRNA within the dentate gyrus might contribute to decreased hippocampal cell proliferation in the APP swe /PS1 ΔE9 mouse AD model. However, it is not known whether the BMP antagonist Noggin contributes to the regulation of neurogenesis. We therefore studied the relative expression levels and localization of BMP4 and its antagonist Noggin in the dentate gyrus and whether these correlated with changes in neurogenesis in 6-12 mo old APP swe /PS1 ΔE9 transgenic mice. Bromodeoxyuridine (BrdU) was used to label proliferative cells. We report that decreased neurogenesis in the APP/PS1 transgenic mice was accompanied by increased expression of BMP4 and decreased expression of Noggin at both the mRNA and protein levels; statistical analysis showed that the number of proliferative cells at different ages correlated positively with Noggin expression and negatively with BMP4 expression. Intraventricular administration of a chimeric Noggin/Fc protein was used to block the action of endogenous BMP4; this resulted in a significant increase in the number of BrdU-labeled cells in dentate gyrus subgranular zone and hilus in APP/PS1 mice. These results suggest that BMP4 and Noggin co-modulate neurogenesis.

  8. High cell density suppresses BMP4-induced differentiation of human pluripotent stem cells to produce macroscopic spatial patterning in a unidirectional perfusion culture chamber.

    Science.gov (United States)

    Tashiro, Shota; Le, Minh Nguyen Tuyet; Kusama, Yuta; Nakatani, Eri; Suga, Mika; Furue, Miho K; Satoh, Taku; Sugiura, Shinji; Kanamori, Toshiyuki; Ohnuma, Kiyoshi

    2018-04-19

    Spatial pattern formation is a critical step in embryogenesis. Bone morphogenetic protein 4 (BMP4) and its inhibitors are major factors for the formation of spatial patterns during embryogenesis. However, spatial patterning of the human embryo is unclear because of ethical issues and isotropic culture environments resulting from conventional culture dishes. Here, we utilized human pluripotent stem cells (hiPSCs) and a simple anisotropic (unidirectional perfusion) culture chamber, which creates unidirectional conditions, to measure the cell community effect. The influence of cell density on BMP4-induced differentiation was explored during static culture using a conventional culture dish. Immunostaining of the early differentiation marker SSEA-1 and the mesendoderm marker BRACHYURY revealed that high cell density suppressed differentiation, with small clusters of differentiated and undifferentiated cells formed. Addition of five-fold higher concentration of BMP4 showed similar results, suggesting that suppression was not caused by depletion of BMP4 but rather by high cell density. Quantitative RT-PCR array analysis showed that BMP4 induced multi-lineage differentiation, which was also suppressed under high-density conditions. We fabricated an elongated perfusion culture chamber, in which proteins were transported unidirectionally, and hiPSCs were cultured with BMP4. At low density, the expression was the same throughout the chamber. However, at high density, SSEA-1 and BRACHYURY were expressed only in upstream cells, suggesting that some autocrine/paracrine factors inhibited the action of BMP4 in downstream cells to form the spatial pattern. Human iPSCs cultured in a perfusion culture chamber might be useful for studying in vitro macroscopic pattern formation in human embryogenesis. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Bone marrow stromal cells with a combined expression of BMP-2 and VEGF-165 enhanced bone regeneration

    International Nuclear Information System (INIS)

    Xiao Caiwen; Zhou Huifang; Fu Yao; Gu Ping; Fan Xianqun; Liu Guangpeng; Zhang Peng; Hou Hongliang; Tang Tingting

    2011-01-01

    Bone graft substitutes with osteogenic factors alone often exhibit poor bone regeneration due to inadequate vascularization. Combined delivery of osteogenic and angiogenic factors from biodegradable scaffolds may enhance bone regeneration. We evaluated the effects of bone morphogenetic protein 2 (BMP2) and vascular endothelial growth factor (VEGF), combined with natural coral scaffolds, on the repair of critical-sized bone defects in rabbit orbits. In vitro expanded rabbit bone marrow stromal cells (BMSCs) were transfected with human BMP2 and VEGF165 genes. Target protein expression and osteogenic differentiation were confirmed after gene transduction. Rabbit orbital defects were treated with a coral scaffold loaded with BMP2-transduced and VEGF-transduced BMSCs, BMP2-expressing BMSCs, VEGF-expressing BMSCs, or BMSCs without gene transduction. Volume and density of regenerated bone were determined by micro-computed tomography at 4, 8, and 16 weeks after implantation. Neovascularity, new bone deposition rate, and new bone formation were measured by immunostaining, tetracycline and calcein labelling, and histomorphometric analysis at different time points. The results showed that VEGF increased blood vessel formation relative to groups without VEGF. Combined delivery of BMP2 and VEGF increased new bone deposition and formation, compared with any single factor. These findings indicate that mimicking the natural bone development process by combined BMP2 and VEGF delivery improves healing of critical-sized orbital defects in rabbits.

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

    Science.gov (United States)

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

    2015-10-01

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

  11. Enhanced Healing of Rat Calvarial Defects with MSCs Loaded on BMP-2 Releasing Chitosan/Alginate/Hydroxyapatite Scaffolds

    Science.gov (United States)

    He, Xiaoning; Liu, Yang; Yuan, Xue; Lu, Li

    2014-01-01

    In this study, we designed a chitosan/alginate/hydroxyapatite scaffold as a carrier for recombinant BMP-2 (CAH/B2), and evaluated the release kinetics of BMP-2. We evaluated the effect of the CAH/B2 scaffold on the viability and differentiation of bone marrow mesenchymal stem cells (MSCs) by scanning electron microscopy, MTS, ALP assay, alizarin-red staining and qRT-PCR. Moreover, MSCs were seeded on scaffolds and used in a 8 mm rat calvarial defect model. New bone formation was assessed by radiology, hematoxylin and eosin staining 12 weeks postoperatively. We found the release kinetics of BMP-2 from the CAH/B2 scaffold were delayed compared with those from collagen gel, which is widely used for BMP-2 delivery. The BMP-2 released from the scaffold increased MSC differentiation and did not show any cytotoxicity. MSCs exhibited greater ALP activity as well as stronger calcium mineral deposition, and the bone-related markers Col1α, osteopontin, and osteocalcin were upregulated. Analysis of in vivo bone formation showed that the CAH/B2 scaffold induced more bone formation than other groups. This study demonstrates that CAH/B2 scaffolds might be useful for delivering osteogenic BMP-2 protein and present a promising bone regeneration strategy. PMID:25084008

  12. BMP-2 functions independently of SHH signaling and triggers cell condensation and apoptosis in regenerating axolotl limbs

    Directory of Open Access Journals (Sweden)

    Finnson Kenneth

    2010-02-01

    Full Text Available Abstract Background Axolotls have the unique ability, among vertebrates, to perfectly regenerate complex body parts, such as limbs, after amputation. In addition, axolotls pattern developing and regenerating autopods from the anterior to posterior axis instead of posterior to anterior like all tetrapods studied to date. Sonic hedgehog is important in establishing this anterior-posterior axis of limbs in all tetrapods including axolotls. Interestingly, its expression is conserved (to the posterior side of limb buds and blastemas in axolotl limbs as in other tetrapods. It has been suggested that BMP-2 may be the secondary mediator of sonic hedgehog, although there is mounting evidence to the contrary in mice. Since BMP-2 expression is on the anterior portion of developing and regenerating limbs prior to digit patterning, opposite to the expression of sonic hedgehog, we examined whether BMP-2 expression was dependent on sonic hedgehog signaling and whether it affects patterning of the autopod during regeneration. Results The expression of BMP-2 and SOX-9 in developing and regenerating axolotl limbs corresponded to the first digits forming in the anterior portion of the autopods. The inhibition of sonic hedgehog signaling with cyclopamine caused hypomorphic limbs (during development and regeneration but did not affect the expression of BMP-2 and SOX-9. Overexpression of BMP-2 in regenerating limbs caused a loss of digits. Overexpression of Noggin (BMP inhibitor in regenerating limbs also resulted in a loss of digits. Histological analysis indicated that the loss due to BMP-2 overexpression was the result of increased cell condensation and apoptosis while the loss caused by Noggin was due to a decrease in cell division. Conclusion The expression of BMP-2 and its target SOX-9 was independent of sonic hedgehog signaling in developing and regenerating limbs. Their expression correlated with chondrogenesis and the appearance of skeletal elements has

  13. HIF-1α as a Regulator of BMP2-Induced Chondrogenic Differentiation, Osteogenic Differentiation, and Endochondral Ossification in Stem Cells

    Directory of Open Access Journals (Sweden)

    Nian Zhou

    2015-04-01

    Full Text Available Background/Aims: Joint cartilage defects are difficult to treat due to the limited self-repair capacities of cartilage. Cartilage tissue engineering based on stem cells and gene enhancement is a potential alternative for cartilage repair. Bone morphogenetic protein 2 (BMP2 has been shown to induce chondrogenic differentiation in mesenchymal stem cells (MSCs; however, maintaining the phenotypes of MSCs during cartilage repair since differentiation occurs along the endochondral ossification pathway. In this study, hypoxia inducible factor, or (HIF-1α, was determined to be a regulator of BMP2-induced chondrogenic differentiation, osteogenic differentiation, and endochondral bone formation. Methods: BMP2 was used to induce chondrogenic and osteogenic differentiation in stem cells and fetal limb development. After HIF-1α was added to the inducing system, any changes in the differentiation markers were assessed. Results: HIF-1α was found to potentiate BMP2-induced Sox9 and the expression of chondrogenesis by downstream markers, and inhibit Runx2 and the expression of osteogenesis by downstream markers in vitro. In subcutaneous stem cell implantation studies, HIF-1α was shown to potentiate BMP2-induced cartilage formation and inhibit endochondral ossification during ectopic bone/cartilage formation. In the fetal limb culture, HIF-1α and BMP2 synergistically promoted the expansion of the proliferating chondrocyte zone and inhibited chondrocyte hypertrophy and endochondral ossification. Conclusion: The results of this study indicated that, when combined with BMP2, HIF-1α induced MSC differentiation could become a new method of maintaining cartilage phenotypes during cartilage tissue engineering.

  14. [miRNA profile of the human dental pulp cells during odontoblast differentiation induced by BMP-2].

    Science.gov (United States)

    Bao, Li-Rong; Zhao, Wen-Qing; Lin, Tian; Lu, Yan-Ling; Wu, Yu

    2017-10-01

    To screen and verify the differentially expressed microRNAs (miRNAs) during the differentiation of human dental pulp cells (hDPCs) to odontoblasts induced by BMP-2. The isolated hDPCs were cultured in vitro and induced by BMP-2. The levels of ALP, DMP-1 and DSPP were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). The potential characteristics of hDPCs were investigated by miRNA microarray and highly expressed miRNAs were selected with bio-information software for predicting target genes and their biological functions. Then the results were validated using qRT-PCR analysis for the selected miRNAs. Statistical analysis was performed using SPSS 18.0 software package. The expression of ALP, DSPP, and DMP-1 showed significantly higher levels in BMP-2 induced groups compared to the control group(Pfunction(33%), while the function of other 0.2% genes remained unknown. This study identified differential expression of miRNAs in BMP-2-induced odontoblastic differentiation of hDPCs, thus contributing to further investigations of regulatory mechanisms and biological effect of target genes in BMP-2-induced odontoblastic differentiation of hDPCs.

  15. Dual delivery of rhPDGF-BB and bone marrow mesenchymal stromal cells expressing the BMP2 gene enhance bone formation in a critical-sized defect model.

    Science.gov (United States)

    Park, Shin-Young; Kim, Kyoung-Hwa; Shin, Seung-Yun; Koo, Ki-Tae; Lee, Yong-Moo; Seol, Yang-Jo

    2013-11-01

    Bone tissue healing is a dynamic, orchestrated process that relies on multiple growth factors and cell types. Platelet-derived growth factor-BB (PDGF-BB) is released from platelets at wound sites and induces cellular migration and proliferation necessary for bone regeneration in the early healing process. Bone morphogenetic protein-2 (BMP-2), the most potent osteogenic differentiation inducer, directs new bone formation at the sites of bone defects. This study evaluated a combinatorial treatment protocol of PDGF-BB and BMP-2 on bone healing in a critical-sized defect model. To mimic the bone tissue healing process, a dual delivery approach was designed to deliver the rhPDGF-BB protein transiently during the early healing phase, whereas BMP-2 was supplied by rat bone marrow stromal cells (BMSCs) transfected with an adenoviral vector containing the BMP2 gene (AdBMP2) for prolonged release throughout the healing process. In in vitro experiments, the dual delivery of rhPDGF-BB and BMP2 significantly enhanced cell proliferation. However, the osteogenic differentiation of BMSCs was significantly suppressed even though the amount of BMP-2 secreted by the AdBMP2-transfected BMSCs was not significantly affected by the rhPDGF-BB treatment. In addition, dual delivery inhibited the mRNA expression of BMP receptor type II and Noggin in BMSCs. In in vivo experiments, critical-sized calvarial defects in rats showed enhanced bone regeneration by dual delivery of autologous AdBMP2-transfected BMSCs and rhPDGF-BB in both the amount of new bone formed and the bone mineral density. These enhancements in bone regeneration were greater than those observed in the group treated with AdBMP2-transfected BMSCs alone. In conclusion, the dual delivery of rhPDGF-BB and AdBMP2-transfected BMSCs improved the quality of the regenerated bone, possibly due to the modulation of PDGF-BB on BMP-2-induced osteogenesis.

  16. NF-kappaB specifically activates BMP-2 gene expression in growth plate chondrocytes in vivo and in a chondrocyte cell line in vitro.

    Science.gov (United States)

    Feng, Jian Q; Xing, Lianping; Zhang, Jiang-Hong; Zhao, Ming; Horn, Diane; Chan, Jeannie; Boyce, Brendan F; Harris, Stephen E; Mundy, Gregory R; Chen, Di

    2003-08-01

    Bone morphogenetic protein-2 (BMP-2) regulates growth plate chondrogenesis during development and postnatal bone growth, but the control mechanisms of BMP-2 expression in growth plate chondrocytes are unknown. Here we have used both in vitro and in vivo approaches to demonstrate that transcription factor, NF-kappaB, regulates BMP-2 gene expression in chondrocytes. Two putative NF-kappaB response elements were found in the -2712/+165 region of the BMP-2 gene. Cotransfection of mutant I-kappaBalpha expression plasmids with BMP-2 promoter-luciferase reporters into TMC-23 chondrocyte cell line suppressed BMP-2 transcription. Mutations in NF-kappaB response elements in the BMP-2 gene lead to decreases in BMP-2 promoter activity. Electrophoretic mobility shift assay using nuclear extracts from TMC-23 chondrocytic cells revealed that the NF-kappaB subunits p50 and p65 bound to the NF-kappaB response elements of the BMP-2 gene. Thus, NF-kappaB may positively regulate BMP-2 gene transcription. Consistent with these findings, expression of BMP-2 mRNA was significantly reduced in growth plate chondrocytes in NF-kappaB p50/p52 dKO mice, which associated with decreased numbers of 5-bromo-2'-deoxyuridine (BrdUrd)-positive cells in the proliferating zone of growth plate in these mice. Therefore, in postnatal growth plate chondrocytes, expression of BMP-2 is regulated by NF-kappaB, which may play an important role in chondrogenesis.

  17. Duplications involving a conserved regulatory element downstream of BMP2 are associated with brachydactyly type A2

    DEFF Research Database (Denmark)

    Dathe, Katarina; Kjaer, Klaus W; Brehm, Anja

    2009-01-01

    Autosomal-dominant brachydactyly type A2 (BDA2), a limb malformation characterized by hypoplastic middle phalanges of the second and fifth fingers, has been shown to be due to mutations in the Bone morphogenetic protein receptor 1B (BMPR1B) or in its ligand Growth and differentiation factor 5 (GDF5......). A linkage analysis performed in a mutation-negative family identified a novel locus for BDA2 on chromosome 20p12.3 that incorporates the gene for Bone morphogenetic protein 2 (BMP2). No point mutation was identified in BMP2, so a high-density array CGH analysis covering the critical interval...... within the identified duplication. Our results reveal an additional functional mechanism for the pathogenesis of BDA2, which is duplication of a regulatory element that affects the expression of BMP2 in the developing limb....

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

    Science.gov (United States)

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

    2017-11-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  20. Differential effects of BMP-2 and TGF-beta1 on chondrogenic differentiation of adipose derived stem cells

    DEFF Research Database (Denmark)

    Mehlhorn, A T; Niemeyer, P; Kaschte, K

    2007-01-01

    transcriptional regulation of Dlx-5, Msx-2 and Runx-2. MATERIALS AND METHODS: Encapsulated ASC were cultured for 14 days in medium containing TGF-beta1 and/or BMP-2. mRNA expression of the extracellular matrix molecules col2a1, cartilage oligomeric matrix protein, col10a1, alkaline phosphatase (AP......) and transcription factors Msx-2, Dlx-5 and Runx-2 was analysed. Release of glycosaminoglycans, collagen types II and X into the extracellular matrix was demonstrated. RESULTS: BMP-2 and TGF-beta1 induced a chondrogenic phenotype in ASC. Combined growth factor treatment had a synergistic effect on col10a1...

  1. Surface modification of 3D-printed porous scaffolds via mussel-inspired polydopamine and effective immobilization of rhBMP-2 to promote osteogenic differentiation for bone tissue engineering.

    Science.gov (United States)

    Lee, Sang Jin; Lee, Donghyun; Yoon, Taek Rim; Kim, Hyung Keun; Jo, Ha Hyeon; Park, Ji Sun; Lee, Jun Hee; Kim, Wan Doo; Kwon, Il Keun; Park, Su A

    2016-08-01

    For tissue engineering, a bio-porous scaffold which is applied to bone-tissue regeneration should provide the hydrophilicity for cell attachment as well as provide for the capability to bind a bioactive molecule such as a growth factor in order to improve cell differentiation. In this work, we prepared a three-dimensional (3D) printed polycaprolactone scaffold (PCLS) grafted with recombinant human bone morphogenic protein-2 (rhBMP2) attached via polydopamine (DOPA) chemistry. The DOPA coated PCL scaffold was characterized by contact angle, water uptake, and X-ray photoelectron spectroscopy (XPS) in order to certify that the surface was successfully coated with DOPA. In order to test the loading and release of rhBMP2, we examined the release rate for 28days. For the In vitro cell study, pre-osteoblast MC3T3-E1 cells were seeded onto PCL scaffolds (PCLSs), DOPA coated PCL scaffold (PCLSD), and scaffolds with varying concentrations of rhBMP2 grafted onto the PCLSD 100 and PCLSD 500 (100 and 500ng/ml loaded), respectively. These scaffolds were evaluated by cell proliferation, alkaline phosphatase activity, and real time polymerase chain reaction with immunochemistry in order to verify their osteogenic activity. Through these studies, we demonstrated that our fabricated scaffolds were well coated with DOPA as well as grafted with rhBMP2 at a quantity of 22.7±5ng when treatment with 100ng/ml rhBMP2 and 153.3±2.4ng when treated with 500ng/ml rhBMP2. This grafting enables rhBMP2 to be released in a sustained pattern. In the in vitro results, the cell proliferation and an osteoconductivity of PCLSD 500 groups was greater than any other group. All of these results suggest that our manufactured 3D printed porous scaffold would be a useful construct for application to the bone tissue engineering field. Tissue-engineered scaffolds are not only extremely complex and cumbersome, but also use organic solvents which can negatively influence cellular function. Thus, a rapid

  2. Select polyphenolic fractions from dried plum enhance osteoblast activity through BMP-2 signaling.

    Science.gov (United States)

    Graef, Jennifer L; Rendina-Ruedy, Elizabeth; Crockett, Erica K; Ouyang, Ping; King, Jarrod B; Cichewicz, Robert H; Lucas, Edralin A; Smith, Brenda J

    2018-05-01

    Dried plum supplementation has been shown to enhance bone formation while suppressing bone resorption. Evidence from previous studies has demonstrated that these responses can be attributed in part to the fruit's polyphenolic compounds. The purpose of this study was to identify the most bioactive polyphenolic fractions of dried plum with a focus on their osteogenic activity and to investigate their mechanisms of action under normal and inflammatory conditions. Utilizing chromatographic techniques, six fractions of polyphenolic compounds were prepared from a crude extract of dried plum. Initial screening assays revealed that two fractions (DP-FrA and DP-FrB) had the greatest osteogenic potential. Subsequent experiments using primary bone-marrow-derived osteoblast cultures demonstrated these two fractions enhanced extracellular alkaline phosphatase (ALP), an indicator of osteoblast activity, and mineralized nodule formation under normal conditions. Both fractions enhanced bone morphogenetic protein (BMP) signaling, as indicated by increased Bmp2 and Runx2 gene expression and protein levels of phosphorylated Smad1/5. DP-FrB was most effective at up-regulating Tak1 and Smad1, as well as protein levels of phospho-p38. Under inflammatory conditions, TNF-α suppressed ALP and tended to decrease nodule formation (P=.0674). This response coincided with suppressed gene expression of Bmp2 and the up-regulation of Smad6, an inhibitor of BMP signaling. DP-FrA and DP-FrB partially normalized these responses. Our results show that certain fractions of polyphenolic compounds in dried plum up-regulate osteoblast activity by enhancing BMP signaling, and when this pathway is inhibited by TNF-α, the osteogenic response is attenuated. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Stiffness-dependent cellular internalization of matrix-bound BMP-2 and its relation to Smad and non-Smad signaling.

    Science.gov (United States)

    Gilde, Flora; Fourel, Laure; Guillot, Raphael; Pignot-Paintrand, Isabelle; Okada, Takaharu; Fitzpatrick, Vincent; Boudou, Thomas; Albiges-Rizo, Corinne; Picart, Catherine

    2016-12-01

    Surface coatings delivering BMP are a promising approach to render biomaterials osteoinductive. In contrast to soluble BMPs which can interact with their receptors at the dorsal side of the cell, BMPs presented as an insoluble cue physically bound to a biomimetic matrix, called here matrix-bound (bBMP-2), are presented to cells by their ventral side. To date, BMP-2 internalization and signaling studies in cell biology have always been performed by adding soluble (sBMP-2) to cells adhered on cell culture plates or glass slides, which will be considered here as a "reference" condition. However, whether and how matrix-bound BMP-2 can be internalized by cells and its relation to canonical (SMAD) and non-canonical signaling (ALP) remain open questions. In this study, we investigated the uptake and processing of BMP-2 by C2C12 myoblasts. This BMP-2 was presented either embedded in polyelectrolyte multilayer films (matrix-bound presentation) or as soluble form. Using fluorescently labeled BMP-2, we showed that the amount of matrix-bound BMP-2 internalized is dependent on the level of crosslinking of the polyelectrolyte films. Cav-1-mediated internalization is related to both SMAD and ALP signaling, while clathrin-mediated is only related to ALP signaling. BMP-2 internalization was independent of the presentation mode (sBMP-2 versus bBMP-2) for low crosslinked films (soft, EDC10) in striking contrast with high crosslinked (stiff, EDC70) films where internalization was much lower and slower for bBMP-2. As anticipated, internalization of sBMP-2 barely depended on the underlying matrix. Taken together, these results indicate that BMP-2 internalization can be tuned by the underlying matrix and activates downstream BMP-2 signaling, which is key for the effective formation of bone tissue. The presentation of growth factors from material surfaces currently presents significant challenges in academic research, clinics and industry. Being able to deliver efficiently these growth

  4. Bone regeneration by gelatin hydro-gel seat containing BMP-2 and its application to canine orbital floor fracture Model

    International Nuclear Information System (INIS)

    Mochizuki, Yuichi

    2007-01-01

    Reported are preparation of the gel seat in the title (GHG) for sustained release of BMP-2 (bone morphogenetic protein-2) and its application to the fracture model of orbital floor of the dog. The chemically linked GHG was prepared from gelatin and glutaraldehyde and lyophilized. BMP-2 solution was dropped on the GHG seat to be contained there. To see the biobehavior of BMP-2 and GHG, they were labeled with 125 I and were given subcutaneously in the back of nude mice, of which remaining radioactivity was periodically measured by Aloka ARC-310B gamma counter. This experiment revealed the sustained release of BMP-2 along with degradation of the GHG. Then a complex of the GHG and bio-degradable polymer (L-lactide-ε-caprolactone) was prepared and implanted to the artificially fractured region (10 x 10 mm) of dog orbit floor, of which recovering process was evaluated by analysis of bone structure with soft X-ray (SOFRON, TRS-1005) roentgenography, histology, and micro-CT imaging (Comscantecno's Scan Xmate-A090S) for trabecular bone volume, thickness, number and separation. This experiment revealed that new bone was effectively induced to regenerate on the complex, of which structure was found similar to the normal trabecula. Thus in future, the complex can be useful for ideal treatment of the orbit floor fracture without necessity of donor. (R.T.)

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

    Science.gov (United States)

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

    2015-03-01

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

  6. Kinetics and thermodynamics studies on the BMP-2 adsorption onto hydroxyapatite surface with different multi-morphological features

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zhiwei; Huangfu, Changxin; Wang, Yanying; Ge, Hongwei; Yao, Yao; Zou, Ping; Wang, Guangtu [College of Science, Sichuan Agricultural University, Ya' an 625014 (China); He, Hua [Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Wenjiang, Sichuan 611130 (China); Rao, Hanbing, E-mail: rhbscu@gmail.com [College of Science, Sichuan Agricultural University, Ya' an 625014 (China)

    2015-07-01

    The effect of the surface topography on protein adsorption process is of great significance for designing hydroxyapatite (HA) ceramic material surfaces. In this work, three different topographies of HA materials HA-sheet, HA-rod, and HA-whisker were synthesized and testified by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer–Emmett–Teller (BET) and a field emission scanning electron microscopy (FE-SEM). We have systematically investigated the adsorption kinetics and thermodynamics of bone morphogenetic proteins (BMP-2) on the three different topography surfaces of HA, respectively. The results showed that the maximum adsorption capacities of HA-sheet, HA-rod and HA-whisker were (219.96 ± 10.18), (247.13 ± 12.35), and (354.67 ± 17.73) μg · g{sup −1}, respectively. Kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated as well as discussed. It demonstrated that the adsorption of BMP-2 onto HA could be described by the pseudo second-order equation. Adsorption of BMP-2 onto HA followed the Langmuir isotherm. It confirmed that compared with other samples HA-whisker had more adsorption sites for its high specific surface area which could provide more opportunities for protein molecules. The adsorption processes were endothermic (ΔH > 0), spontaneous (ΔG < 0) and entropy increasing (ΔS > 0). A possible adsorption mechanism has been proposed. In addition, the BMP-2 could be adsorbed to the surface which existed slight conformational changes by FT-IR. - Highlights: • A novel protein adsorption studies based on sheet, rod and whisker of HA were designed. • Kinetic and thermodynamics parameters of BMP-2 and HA bonded materials were evaluated. • Surface topographies of the HA effect BMP-2 adsorption • The HA-whisker material had excellent adsorption performance for protein enrichment. • The electrostatic interaction is responsible for the

  7. Kinetics and thermodynamics studies on the BMP-2 adsorption onto hydroxyapatite surface with different multi-morphological features

    International Nuclear Information System (INIS)

    Lu, Zhiwei; Huangfu, Changxin; Wang, Yanying; Ge, Hongwei; Yao, Yao; Zou, Ping; Wang, Guangtu; He, Hua; Rao, Hanbing

    2015-01-01

    The effect of the surface topography on protein adsorption process is of great significance for designing hydroxyapatite (HA) ceramic material surfaces. In this work, three different topographies of HA materials HA-sheet, HA-rod, and HA-whisker were synthesized and testified by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer–Emmett–Teller (BET) and a field emission scanning electron microscopy (FE-SEM). We have systematically investigated the adsorption kinetics and thermodynamics of bone morphogenetic proteins (BMP-2) on the three different topography surfaces of HA, respectively. The results showed that the maximum adsorption capacities of HA-sheet, HA-rod and HA-whisker were (219.96 ± 10.18), (247.13 ± 12.35), and (354.67 ± 17.73) μg · g −1 , respectively. Kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated as well as discussed. It demonstrated that the adsorption of BMP-2 onto HA could be described by the pseudo second-order equation. Adsorption of BMP-2 onto HA followed the Langmuir isotherm. It confirmed that compared with other samples HA-whisker had more adsorption sites for its high specific surface area which could provide more opportunities for protein molecules. The adsorption processes were endothermic (ΔH > 0), spontaneous (ΔG < 0) and entropy increasing (ΔS > 0). A possible adsorption mechanism has been proposed. In addition, the BMP-2 could be adsorbed to the surface which existed slight conformational changes by FT-IR. - Highlights: • A novel protein adsorption studies based on sheet, rod and whisker of HA were designed. • Kinetic and thermodynamics parameters of BMP-2 and HA bonded materials were evaluated. • Surface topographies of the HA effect BMP-2 adsorption • The HA-whisker material had excellent adsorption performance for protein enrichment. • The electrostatic interaction is responsible for the BMP-2

  8. Low-dose rhBMP2/7 heterodimer to reconstruct peri-implant bone defects: a micro-CT evaluation

    NARCIS (Netherlands)

    Wang, J.; Zheng, Y.; Zhao, J.; Liu, T.; Gao, L.; Gu, Z.; Wu, G.

    2012-01-01

    Objectives To delineate the dynamic micro-architectures of bone induced by low-dose bone morphogenetic protein (BMP)-2/7 heterodimer in peri-implant bone defects compared to BMP2 and BMP7 homodimer. Material and Methods Peri-implant bone defects (8 mm in diameter, 4 mm in depth) were created

  9. Time kinetics of bone defect healing in response to BMP-2 and GDF-5 characterised by in vivo biomechanics

    Directory of Open Access Journals (Sweden)

    D Wulsten

    2011-02-01

    Full Text Available This study reports that treatment of osseous defects with different growth factors initiates distinct rates of repair. We developed a new method for monitoring the progression of repair, based upon measuring the in vivo mechanical properties of healing bone. Two different members of the bone morphogenetic protein (BMP family were chosen to initiate defect healing: BMP-2 to induce osteogenesis, and growth-and-differentiation factor (GDF-5 to induce chondrogenesis. To evaluate bone healing, BMPs were implanted into stabilised 5 mm bone defects in rat femurs and compared to controls. During the first two weeks, in vivo biomechanical measurements showed similar values regardless of the treatment used. However, 2 weeks after surgery, the rhBMP-2 group had a substantial increase in stiffness, which was supported by the imaging modalities. Although the rhGDF-5 group showed comparable mechanical properties at 6 weeks as the rhBMP-2 group, the temporal development of regenerating tissues appeared different with rhGDF-5, resulting in a smaller callus and delayed tissue mineralisation. Moreover, histology showed the presence of cartilage in the rhGDF-5 group whereas the rhBMP-2 group had no cartilaginous tissue.Therefore, this study shows that rhBMP-2 and rhGDF-5 treated defects, under the same conditions, use distinct rates of bone healing as shown by the tissue mechanical properties. Furthermore, results showed that in vivo biomechanical method is capable of detecting differences in healing rate by means of change in callus stiffness due to tissue mineralisation.

  10. Myocardial Tbx20 regulates early atrioventricular canal formation and endocardial epithelial-mesenchymal transition via Bmp2.

    Science.gov (United States)

    Cai, Xiaoqiang; Nomura-Kitabayashi, Aya; Cai, Weibin; Yan, Jianyun; Christoffels, Vincent M; Cai, Chen-Leng

    2011-12-15

    During early embryogenesis, the formation of the cardiac atrioventricular canal (AVC) facilitates the transition of the heart from a linear tube into a chambered organ. However, the genetic pathways underlying this developmental process are poorly understood. The T-box transcription factor Tbx20 is expressed predominantly in the AVC of early heart tube. It was shown that Tbx20 activates Nmyc1 and suppresses Tbx2 expression to promote proliferation and specification of the atrial and ventricular chambers, yet it is not known if Tbx20 is involved in early AVC development. Here, we report that mice lacking Tbx20 in the AVC myocardium fail to form the AVC constriction, and the endocardial epithelial-mesenchymal transition (EMT) is severely perturbed. Tbx20 maintains expression of a variety of genes, including Bmp2, Tbx3 and Hand1 in the AVC myocardium. Intriguingly, we found Bmp2 downstream genes involved in the EMT initiation are also downregulated. In addition, re-expression of Bmp2 in the AVC myocardium substantially rescues the EMT defects resulting from the lack of Tbx20, suggesting Bmp2 is one of the key downstream targets of Tbx20 in AVC development. Our data support a complex signaling network with Tbx20 suppressing Tbx2 in the AVC myocardium but also indirectly promoting Tbx2 expression through Bmp2. The spatiotemporal expression of Tbx2 in the AVC appears to be balanced between these two opposing signals. Overall, our study provides genetic evidence that Tbx20 has essential roles in regulating AVC development that coordinate early cardiac chamber formation. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. In silico Mechano-Chemical Model of Bone Healing for the Regeneration of Critical Defects: The Effect of BMP-2.

    Directory of Open Access Journals (Sweden)

    Frederico O Ribeiro

    Full Text Available The healing of bone defects is a challenge for both tissue engineering and modern orthopaedics. This problem has been addressed through the study of scaffold constructs combined with mechanoregulatory theories, disregarding the influence of chemical factors and their respective delivery devices. Of the chemical factors involved in the bone healing process, bone morphogenetic protein-2 (BMP-2 has been identified as one of the most powerful osteoinductive proteins. The aim of this work is to develop and validate a mechano-chemical regulatory model to study the effect of BMP-2 on the healing of large bone defects in silico. We first collected a range of quantitative experimental data from the literature concerning the effects of BMP-2 on cellular activity, specifically proliferation, migration, differentiation, maturation and extracellular matrix production. These data were then used to define a model governed by mechano-chemical stimuli to simulate the healing of large bone defects under the following conditions: natural healing, an empty hydrogel implanted in the defect and a hydrogel soaked with BMP-2 implanted in the defect. For the latter condition, successful defect healing was predicted, in agreement with previous in vivo experiments. Further in vivo comparisons showed the potential of the model, which accurately predicted bone tissue formation during healing, bone tissue distribution across the defect and the quantity of bone inside the defect. The proposed mechano-chemical model also estimated the effect of BMP-2 on cells and the evolution of healing in large bone defects. This novel in silico tool provides valuable insight for bone tissue regeneration strategies.

  12. Bone Morphogenetic Protein (BMP-4 and BMP-7 regulate differentially Transforming Growth Factor (TGF-β1 in normal human lung fibroblasts (NHLF

    Directory of Open Access Journals (Sweden)

    Lloyd Clare M

    2010-06-01

    Full Text Available Abstract Background Airway remodelling is thought to be under the control of a complex group of molecules belonging to the Transforming Growth Factor (TGF-superfamily. The Bone Morphogenetic Proteins (BMPs belong to this family and have been shown to regulate fibrosis in kidney and liver diseases. However, the role of BMPs in lung remodelling remains unclear. BMPs may regulate tissue remodelling in asthma by controlling TGF-β-induced profibrotic functions in lung fibroblasts. Methods Cell cultures were exposed to TGF-β1 alone or in the presence of BMP-4 or BMP-7; control cultures were exposed to medium only. Cell proliferation was assessed by quantification of the incorporation of [3H]-thymidine. The expression of the mRNA encoding collagen type I and IV, tenascin C and fibronectin in normal human lung fibroblasts (NHLF was determined by real-time quantitative PCR and the main results were confirmed by ELISA. Cell differentiation was determined by the analysis of the expression of α-smooth muscle actin (α-SMA by western blot and immunohistochemistry. The effect on matrix metalloproteinase (MMP activity was assessed by zymography. Results We have demonstrated TGF-β1 induced upregulation of mRNAs encoding the extracellular matrix proteins, tenascin C, fibronectin and collagen type I and IV when compared to unstimulated NHLF, and confirmed these results at the protein level. BMP-4, but not BMP-7, reduced TGF-β1-induced extracellular matrix protein production. TGF-β1 induced an increase in the activity of the pro-form of MMP-2 which was inhibited by BMP-7 but not BMP-4. Both BMP-4 and BMP-7 downregulated TGF-β1-induced MMP-13 release compared to untreated and TGF-β1-treated cells. TGF-β1 also induced a myofibroblast-like transformation which was partially inhibited by BMP-7 but not BMP-4. Conclusions Our study suggests that some regulatory properties of BMP-7 may be tissue or cell type specific and unveil a potential regulatory role for

  13. Repair of Cranial Bone Defects Using rhBMP2 and Submicron Particle of Biphasic Calcium Phosphate Ceramics with Through-Hole

    Directory of Open Access Journals (Sweden)

    Byung-Chul Jeong

    2015-01-01

    Full Text Available Recently a submicron particle of biphasic calcium phosphate ceramic (BCP with through-hole (donut-shaped BCP (d-BCP was developed for improving the osteoconductivity. This study was performed to examine the usefulness of d-BCP for the delivery of osteoinductive rhBMP2 and the effectiveness on cranial bone regeneration. The d-BCP was soaked in rhBMP2 solution and then freeze-dried. Scanning electron microscope (SEM, energy dispersive spectroscopy (EDS, and Raman spectroscopy analyses confirmed that rhBMP2 was well delivered onto the d-BCP surface and the through-hole. The bioactivity of the rhBMP2/d-BCP composite was validated in MC3T3-E1 cells as an in vitro model and in critical-sized cranial defects in C57BL/6 mice. When freeze-dried d-BCPs with rhBMP2 were placed in transwell inserts and suspended above MC3T3-E1, alkaline phosphatase activity and osteoblast-specific gene expression were increased compared to non-rhBMP2-containing d-BCPs. For evaluating in vivo effectiveness, freeze-dried d-BCPs with or without rhBMP2 were implanted into critical-sized cranial defects. Microcomputed tomography and histologic analysis showed that rhBMP2-containing d-BCPs significantly enhanced cranial bone regeneration compared to non-rhBMP2-containing control. These results suggest that a combination of d-BCP and rhBMP2 can accelerate bone regeneration, and this could be used to develop therapeutic strategies in hard tissue healing.

  14. Repair of Cranial Bone Defects Using rhBMP2 and Submicron Particle of Biphasic Calcium Phosphate Ceramics with Through-Hole.

    Science.gov (United States)

    Jeong, Byung-Chul; Choi, Hyuck; Hur, Sung-Woong; Kim, Jung-Woo; Oh, Sin-Hye; Kim, Hyun-Seung; Song, Soo-Chang; Lee, Keun-Bae; Park, Kwang-Bum; Koh, Jeong-Tae

    2015-01-01

    Recently a submicron particle of biphasic calcium phosphate ceramic (BCP) with through-hole (donut-shaped BCP (d-BCP)) was developed for improving the osteoconductivity. This study was performed to examine the usefulness of d-BCP for the delivery of osteoinductive rhBMP2 and the effectiveness on cranial bone regeneration. The d-BCP was soaked in rhBMP2 solution and then freeze-dried. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and Raman spectroscopy analyses confirmed that rhBMP2 was well delivered onto the d-BCP surface and the through-hole. The bioactivity of the rhBMP2/d-BCP composite was validated in MC3T3-E1 cells as an in vitro model and in critical-sized cranial defects in C57BL/6 mice. When freeze-dried d-BCPs with rhBMP2 were placed in transwell inserts and suspended above MC3T3-E1, alkaline phosphatase activity and osteoblast-specific gene expression were increased compared to non-rhBMP2-containing d-BCPs. For evaluating in vivo effectiveness, freeze-dried d-BCPs with or without rhBMP2 were implanted into critical-sized cranial defects. Microcomputed tomography and histologic analysis showed that rhBMP2-containing d-BCPs significantly enhanced cranial bone regeneration compared to non-rhBMP2-containing control. These results suggest that a combination of d-BCP and rhBMP2 can accelerate bone regeneration, and this could be used to develop therapeutic strategies in hard tissue healing.

  15. Lack of Obvious Influence of PLLA Nanofibers on the Gene Expression of BMP-2 and VEGF during Growth and Differentiation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Markus D. Schofer

    2009-01-01

    Full Text Available Growth factors like bone morphogenetic protein 2 (BMP-2 and vascular endothelial growth factor (VEGF play an important role in bone remodeling and fracture repair. Therefore, with respect to tissue engineering, an artificial graft should have no negative impact on the expression of these factors. In this context, the aim of this study was to analyze the impact of poly(L-lactic acid (PLLA nanofibers on VEGF and BMP-2 gene expression during the time course of human mesenchymal stem cell (hMSC differentiation towards osteoblasts. PLLA matrices were seeded with hMSCs and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of VEGF and BMP-2. Furthermore, BMP-2–enwoven PLLA nanofibers were used in order to elucidate whether initial down-regulation of growth factor expression could be compensated. Although there was a great interpatient variability with respect to the expression of VEGF and BMP-2, PLLA nanofibers tend to result in a down-regulation in BMP-2 expression during the early phase of cultivation. This effect was diminished in the case of VEGF gene expression. The initial down-regulation was overcome when BMP-2 was directly incorporated into the PLLA nanofibers by electrospinning. Furthermore, the incorporation of BMP-2 into the PLLA nanofibers resulted in an increase in VEGF gene expression. Summarized, the results indicate that the PLLA nanofibers have little effect on growth factor production. An enhancement in gene expression of BMP-2 and VEGF can be achieved by an incorporation of BMP-2 into the PLLA nanofibers.

  16. Lack of Obvious Influence of PLLA Nanofibers on the Gene Expression of BMP-2 and VEGF during Growth and Differentiation of Human Mesenchymal Stem Cells

    Science.gov (United States)

    Schofer, Markus D.; Fuchs-Winkelmann, S.; Wack, C.; Rudisile, M.; Dersch, R.; Leifeld, I.; Wendorff, J.; Greiner, A.; Paletta, J. R. J.; Boudriot, U.

    2009-01-01

    Growth factors like bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF) play an important role in bone remodeling and fracture repair. Therefore, with respect to tissue engineering, an artificial graft should have no negative impact on the expression of these factors. In this context, the aim of this study was to analyze the impact of poly(L-lactic acid) (PLLA) nanofibers on VEGF and BMP-2 gene expression during the time course of human mesenchymal stem cell (hMSC) differentiation towards osteoblasts. PLLA matrices were seeded with hMSCs and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of VEGF and BMP-2. Furthermore, BMP-2–enwoven PLLA nanofibers were used in order to elucidate whether initial down-regulation of growth factor expression could be compensated. Although there was a great interpatient variability with respect to the expression of VEGF and BMP-2, PLLA nanofibers tend to result in a down-regulation in BMP-2 expression during the early phase of cultivation. This effect was diminished in the case of VEGF gene expression. The initial down-regulation was overcome when BMP-2 was directly incorporated into the PLLA nanofibers by electrospinning. Furthermore, the incorporation of BMP-2 into the PLLA nanofibers resulted in an increase in VEGF gene expression. Summarized, the results indicate that the PLLA nanofibers have little effect on growth factor production. An enhancement in gene expression of BMP-2 and VEGF can be achieved by an incorporation of BMP-2 into the PLLA nanofibers. PMID:19412560

  17. Localization of Bmp-4, Shh and Wnt-5a transcripts during early mice tooth development by in situ hybridization Localização de transcritos de Bmp-4, Shh e Wnt-5a durante as fases iniciais do desenvolvimento dentário de camundongos por hibridização in situ

    Directory of Open Access Journals (Sweden)

    Fábio Daumas Nunes

    2007-06-01

    Full Text Available A comparative nonisotopic in situ hybridization (ISH analysis was carried out for the detection of Bmp-4, Shh and Wnt-5a transcripts during mice odontogenesis from initiation to cap stage. Bmp-4 was expressed early in the epithelium and then in the underlying mesenchyme. Shh expression was seen in the odontogenic epithelial lining thickening, being stronger in the enamel knot area, during the cap stage. Wnt-5a transcripts were expressed only in the mesenchyme during the initiation, bud and cap stages, with strong expression in the dental mesenchyme during the bud stage. The present results showed that Bmp-4, Shh and Wnt-5a are expressed since the very early stages of tooth development, and they suggest that the Wnt-5a gene is expressed in different cell populations than Bmp-4 and Shh.No presente trabalho, realizou-se uma análise comparativa não isotópica por hibridização in situ a fim de se detectar a presença de transcritos de Bmp-4, Shh e Wnt-5a durante as fases iniciais da odontogênese em camundongos, desde a iniciação até o estágio de capuz. No estágio de iniciação, observou-se expressão precoce de Bmp-4 no epitélio e no mesênquima subjacente, enquanto que a expressão de Shh ocorreu durante o estágio de capuz, na região de espessamento do revestimento epitelial odontogênico, tornando-se mais intensa na área de nó do esmalte. Os transcritos de Wnt-5a foram expressos somente no mesênquima durante os estágios de iniciação, botão e capuz, com intenso sinal na região no mesênquima na fase de botão. Estes resultados mostraram que Bmp-4, Shh e Wnt-5a são expressos desde os estágios mais precoces do desenvolvimento dentário, sugerindo que o gene Wnt-5a seja expresso em populações celulares distintas daquelas que expressam Bmp-4 e Shh.

  18. BMP4 and BMP7 Suppress StAR and Progesterone Production via ALK3 and SMAD1/5/8-SMAD4 in Human Granulosa-Lutein Cells.

    Science.gov (United States)

    Zhang, Han; Klausen, Christian; Zhu, Hua; Chang, Hsun-Ming; Leung, Peter C K

    2015-11-01

    Adequate production of progesterone by the corpus luteum is critical to the successful establishment of pregnancy. In animal models, bone morphogenetic protein (BMP) 4 and BMP7 have been shown to suppress either basal or gonadotropin-induced progesterone production, depending on the species examined. However, the effects of BMP4 and BMP7 on progesterone production in human granulosa cells are unknown. In the present study, we used immortalized (SVOG) and primary human granulosa-lutein cells to investigate the effects of BMP4 and BMP7 on steroidogenic acute regulatory protein (StAR) expression and progesterone production and to examine the underlying molecular mechanism. Treatment of primary and immortalized human granulosa cells with recombinant BMP4 or BMP7 decreased StAR expression and progesterone accumulation. In SVOG cells, the suppressive effects of BMP4 and BMP7 on StAR expression were blocked by pretreatment with inhibitors of activin receptor-like kinase (ALK)2/3/6 (dorsomorphin) or ALK2/3 (DMH1) but not ALK4/5/7 (SB-431542). Moreover, small interfering RNA-mediated depletion of ALK3, but not ALK2 or ALK6, reversed the effects of BMP4 and BMP7 on StAR expression. Likewise, BMP4- and BMP7-induced phosphorylation of SMAD 1/5/8 was reversed by treatment with DMH1 or small interfering RNA targeting ALK3. Knockdown of SMAD4, the essential common SMAD for BMP/TGF-β signaling, abolished the effects of BMP4 and BMP7 on StAR expression. Our results suggest that BMP4 and BMP7 down-regulate StAR and progesterone production via ALK3 and SMAD1/5/8-SMAD4 signaling in human granulosa-lutein cells.

  19. Assessment of a polyelectrolyte multilayer film coating loaded with BMP-2 on titanium and PEEK implants in the rabbit femoral condyle

    Science.gov (United States)

    Guillot, R.; Pignot-Paintrand, I.; Lavaud, J.; Decambron, A.; Bourgeois, E.; Josserand, V.; Logeart-Avramoglou, D.; Viguier, E.; Picart, C.

    2016-01-01

    The aim of this study was to evaluate the osseointegration of titanium implants (Ti-6Al-4V, noted here TA6V) and poly(etheretherketone) PEEK implants induced by a BMP-2-delivering surface coating made of polyelectrolyte multilayer films. The in vitro bioactivity of the polyelectrolyte film-coated implants was assessed using the alkaline phosphatase assay. BMP-2-coated TA6V and PEEK implants with a total dose of 9.3 µg of BMP-2 were inserted into the femoral condyles of New Zealand white rabbits and compared to uncoated implants. Rabbits were sacrificed 4 and 8 weeks after implantation. Histomorphometric analyses on TA6V and PEEK implants and microcomputed tomography on PEEK implants revealed that the bone-to-implant contact and bone area around the implants were significantly lower for the BMP-2-coated implants than for the bare implants. This was confirmed by scanning electron microscopy imaging. This difference was more pronounced at 4 weeks in comparison to the 8-week time point. However, bone growth inside the hexagonal upper hollow cavity of the screws was higher in the case of the BMP-2 coated implants. Overall, this study shows that a high dose of BMP-2 leads to localized and temporary bone impairment, and that the dose of BMP-2 delivered at the surface of an implant needs to be carefully optimized. PMID:26965394

  20. A Long-Acting BMP-2 Release System Based on Poly(3-hydroxybutyrate) Nanoparticles Modified by Amphiphilic Phospholipid for Osteogenic Differentiation

    Science.gov (United States)

    Peng, Xiaochun; Chen, Yunsu; Li, Yamin; Wang, Yiming

    2016-01-01

    We explored a novel poly(3-hydroxybutyrate) (PHB) nanoparticle loaded with hydrophilic recombinant human BMP-2 with amphiphilic phospholipid (BPC-PHB NP) for a rapid-acting and long-acting delivery system of BMP-2 for osteogenic differentiation. The BPC-PHB NPs were prepared by a solvent evaporation method and showed a spherical particle with a mean particle size of 253.4 nm, mean zeta potential of −22.42 mV, and high entrapment efficiency of 77.18%, respectively. For BPC-PHB NPs, a short initial burst release of BMP-2 from NPs in 24 h was found and it has steadily risen to reach about 80% in 20 days for in vitro test. BPC-PHB NPs significantly reduced the burst release of BMP-2, as compared to that of PHB NPs loading BMP-2 without PL (B-PHB NPs). BPC-PHB NPs maintained the content of BMP-2 for a long-term osteogenic differentiation. The OCT-1 cells with BPC-PHB NPs have high ALP activity in comparison with others. The gene markers for osteogenic differentiation were significantly upregulated for sample with BPC-PHB NPs, implying that BPC-PHB NPs can be used as a rapid-acting and long-acting BMP-2 delivery system for osteogenic differentiation. PMID:27379249

  1. Injectable perlecan domain 1-hyaluronan microgels potentiate the cartilage repair effect of BMP2 in a murine model of early osteoarthritis

    International Nuclear Information System (INIS)

    Srinivasan, Padma P; McCoy, Sarah Y; Yang Weidong; Farach-Carson, Mary C; Kirn-Safran, Catherine B; Jha, Amit K; Jia Xinqiao

    2012-01-01

    The goal of this study was to use bioengineered injectable microgels to enhance the action of bone morphogenetic protein 2 (BMP2) and stimulate cartilage matrix repair in a reversible animal model of osteoarthritis (OA). A module of perlecan (PlnD1) bearing heparan sulfate (HS) chains was covalently immobilized to hyaluronic acid (HA) microgels for the controlled release of BMP2 in vivo. Articular cartilage damage was induced in mice using a reversible model of experimental OA and was treated by intra-articular injection of PlnD1-HA particles with BMP2 bound to HS. Control injections consisted of BMP2-free PlnD1-HA particles, HA particles, free BMP2 or saline. Knees dissected following these injections were analyzed using histological, immunostaining and gene expression approaches. Our results show that knees treated with PlnD1-HA/BMP2 had lesser OA-like damage compared to control knees. In addition, the PlnD1-HA/BMP2-treated knees had higher mRNA levels encoding for type II collagen, proteoglycans and xylosyltransferase 1, a rate-limiting anabolic enzyme involved in the biosynthesis of glycosaminoglycan chains, relative to control knees (PlnD1-HA). This finding was paralleled by enhanced levels of aggrecan in the articular cartilage of PlnD1-HA/BMP2-treated knees. Additionally, decreases in the mRNA levels encoding for cartilage-degrading enzymes and type X collagen were seen relative to controls. In conclusion, PlnD1-HA microgels constitute a formulation improvement compared to HA for efficient in vivo delivery and stimulation of proteoglycan and cartilage matrix synthesis in mouse articular cartilage. Ultimately, PlnD1-HA/BMP2 may serve as an injectable therapeutic agent for slowing or inhibiting the onset of OA after knee injury.

  2. Gallic acid inhibits vascular calcification through the blockade of BMP2-Smad1/5/8 signaling pathway.

    Science.gov (United States)

    Kee, Hae Jin; Cho, Soo-Na; Kim, Gwi Ran; Choi, Sin Young; Ryu, Yuhee; Kim, In Kyeom; Hong, Young Joon; Park, Hyung Wook; Ahn, Youngkeun; Cho, Jeong Gwan; Park, Jong Chun; Jeong, Myung Ho

    2014-11-01

    Vascular calcification is associated with increased risk of morbidity and mortality in patients with cardiovascular diseases, chronic kidney diseases, and diabetes. Gallic acid, a natural compound found in gallnut and green tea, is known to be antifungal, antioxidant, and anticancer. Here we investigated the effect of gallic acid on vascular smooth muscle cell (VSMC) calcification and the underlying mechanism. Gallic acid inhibited inorganic phosphate-induced osteoblast differentiation markers as well as calcification phenotypes (as determined by calcium deposition, Alizarin Red, and Von Kossa staining). Knockdown of BMP2 or Noggin blocked phosphate-induced calcification. Gallic acid suppressed phosphorylation of Smad1/5/8 protein induced by inorganic phosphate. Taken together, we suggest that gallic acid acts as a novel therapeutic agent of vascular calcification by mediating BMP2-Smad1/5/8 signaling pathway. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. E. coli-Produced BMP-2 as a Chemopreventive Strategy for Colon Cancer: A Proof-of-Concept Study

    Directory of Open Access Journals (Sweden)

    Saravanan Yuvaraj

    2012-01-01

    Full Text Available Colon cancer is a serious health problem, and novel preventive and therapeutical avenues are urgently called for. Delivery of proteins with anticancer activity through genetically modified bacteria provides an interesting, potentially specific, economic and effective approach here. Interestingly, bone morphogenetic protein 2 (BMP-2 is an important and powerful tumour suppressor in the colon and is thus an attractive candidate protein for delivery through genetically modified bacteria. It has not been shown, however, that BMP production in the bacterial context is effective on colon cancer cells. Here we demonstrate that transforming E. coli with a cDNA encoding an ileal-derived mature human BMP-2 induces effective apoptosis in an in vitro model system for colorectal cancer, whereas the maternal organism was not effective in this respect. Furthermore, these effects were sensitive to cotreatment with the BMP inhibitor Noggin. We propose that prevention and treatment of colorectal cancer using transgenic bacteria is feasible.

  4. Effect of implantation of biodegradable magnesium alloy on BMP-2 expression in bone of ovariectomized osteoporosis rats

    International Nuclear Information System (INIS)

    Guo, Yue; Ren, Ling; Liu, Chang; Yuan, Yajiang; Lin, Xiao; Tan, Lili; Chen, Shurui; Yang, Ke; Mei, Xifan

    2013-01-01

    The study was focused on the implantation of a biodegradable AZ31 magnesium alloy into the femoral periosteal of the osteoporosis modeled rats. The experimental results showed that after 4 weeks implantation of AZ31 alloy in the osteoporosis modeled rats, the expression of BMP-2 in bone tissues of the rats was much enhanced, even higher than the control group, which should promote the bone formation and be beneficial for reducing the harmful effect of osteoporosis. Results of HE stains showed that the implantation of AZ31 alloy did not have obvious pathological changes on both the liver and kidney of the animal. - Highlights: • Mg alloy greatly increased expression of BMP-2 in osteoporosis modeled rat bone. • Mg alloy showed good biological safety. • Mg alloy is beneficial for reducing the symptom of osteoporosis

  5. The Effects of rhBMP-2 Used for Spinal Fusion on Spinal Cord Pathology After Traumatic Injury

    Science.gov (United States)

    2009-07-29

    1219-1224; discussion 1225. Basso DM , Beattie MS, Bresnahan JC (1995) A sensitive and reliable locomotor rating scale for open field testing in rats...usage of rhBMP-2 in the anterior cervical spine. Spine 31:2813-2819. Stuesse SL, Crisp T, McBurney DL, Schechter JB, Lovell JA, Cruce WL (2001...250-256. Stuesse SL, Crisp T, McBurney DL, Schechter JB, Lovell JA, Cruce WL (2001) Neuropathic pain in aged rats: behavioral responses and

  6. Kinetics and thermodynamics studies on the BMP-2 adsorption onto hydroxyapatite surface with different multi-morphological features.

    Science.gov (United States)

    Lu, Zhiwei; Huangfu, Changxin; Wang, Yanying; Ge, Hongwei; Yao, Yao; Zou, Ping; Wang, Guangtu; He, Hua; Rao, Hanbing

    2015-01-01

    The effect of the surface topography on protein adsorption process is of great significance for designing hydroxyapatite (HA) ceramic material surfaces. In this work, three different topographies of HA materials HA-sheet, HA-rod, and HA-whisker were synthesized and testified by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), Brunauer-Emmett-Teller (BET) and a field emission scanning electron microscopy (FE-SEM). We have systematically investigated the adsorption kinetics and thermodynamics of bone morphogenetic proteins (BMP-2) on the three different topography surfaces of HA, respectively. The results showed that the maximum adsorption capacities of HA-sheet, HA-rod and HA-whisker were (219.96 ± 10.18), (247.13 ± 12.35), and (354.67 ± 17.73) μg · g(-1), respectively. Kinetic parameters, rate constants, equilibrium adsorption capacities and related correlation coefficients, for each kinetic model were calculated as well as discussed. It demonstrated that the adsorption of BMP-2 onto HA could be described by the pseudo second-order equation. Adsorption of BMP-2 onto HA followed the Langmuir isotherm. It confirmed that compared with other samples HA-whisker had more adsorption sites for its high specific surface area which could provide more opportunities for protein molecules. The adsorption processes were endothermic (ΔH > 0), spontaneous (ΔG 0). A possible adsorption mechanism has been proposed. In addition, the BMP-2 could be adsorbed to the surface which existed slight conformational changes by FT-IR. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Repair of rabbit radial bone defects using true bone ceramics combined with BMP-2-related peptide and type I collagen

    International Nuclear Information System (INIS)

    Li Jingfeng; Lin Zhenyu; Zheng Qixin; Guo Xiaodong; Lan Shenghui; Liu Sunan; Yang Shuhua

    2010-01-01

    An ideal bone graft material is the one characterized with good biocompatibility, biodegradation, osteoconductivity and osteoinductivity. In this study, a novel synthetic BMP-2-related peptide (designated P24) corresponding to residues of the knuckle epitope of BMP-2 was introduced into a biomimetic scaffold based on sintered bovine bone or true bone ceramics (TBC) and type I collagen (TBC/collagen I) using a simulated body fluid (SBF). Hydroxylapatite crystal mineralization with a Ca/P molar ratio of 1.63 was observed on the surface of P24/TBC/collagen I composite by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) techniques. Cell adhesion rate evaluation of bone marrow stromal cells (BMSCs) seeded on materials in vitro showed that the percentage of cells attached to P24/TBC/collagen I composite was significantly higher than that of the TBC/collagen I composite. A 10 mm unilateral segmental bone defect was created in the radius of New Zealand white rabbits and randomly implanted with three groups of biomaterials (Group A: P24/TBC/collagen I composite; Group B: TBC/collagen I composite and Group C: TBC alone). Based on radiographic evaluation and histological examination, the implants of P24/TBC/collagen I composite significantly stimulated bone growth, thereby confirming the enhanced rate of bone healing compared with that of TBC/collagen I composite and TBC alone. It was concluded that BMP-2-related peptide P24 could induce nucleation of calcium phosphate crystals on the surface of TBC/collagen I composite. The TBC/collagen I composite loaded with the synthetic BMP-2-related peptide is a promising scaffold biomaterial for bone tissue engineering.

  8. BMP2 induced osteogenic differentiation of human umbilical cord stem cells in a peptide-based hydrogel scaffold

    Science.gov (United States)

    Lakshmana, Shruthi M.

    Craniofacial tissue loss due to traumatic injuries and congenital defects is a major clinical problem around the world. Cleft palate is the second most common congenital malformation in the United States occurring with an incidence of 1 in 700. Some of the problems associated with this defect are feeding difficulties, speech abnormalities and dentofacial anomalies. Current treatment protocol offers repeated surgeries with extended healing time. Our long-term goal is to regenerate bone in the palatal region using tissue-engineering approaches. Bone tissue engineering utilizes osteogenic cells, osteoconductive scaffolds and osteoinductive signals. Mesenchymal stem cells derived from human umbilical cord (HUMSCs) are highly proliferative with the ability to differentiate into osteogenic precursor cells. The primary objective of the study was to characterize HUMSCs and culture them in a 3D hydrogel scaffold and investigate their osteogenic potential. PuraMatrix(TM) is an injectable 3D nanofiber scaffold capable of self-assembly when exposed to physiologic conditions. Our second objective was to investigate the effect of Bone Morphogenic Protein 2 (BMP2) in enhancing the osteogenic differentiation of HUMSCs encapsulated in PuraMatrix(TM). We isolated cells isolated from Wharton's Jelly region of the umbilical cord obtained from NDRI (New York, NY). Isolated cells satisfied the minimal criteria for mesenchymal stem cells (MSCs) as defined by International Society of Cell Therapy in terms of plastic adherence, fibroblastic phenotype, surface marker expression and osteogenic differentiation. Flow Cytometry analysis showed that cells were positive for CD73, CD90 and CD105 while negative for hematopoietic marker CD34. Alkaline phosphatase activity (ALP) of HUMSCs showed peak activity at 2 weeks (p<0.05). Cells were encapsulated in 0.2% PuraMatrix(TM) at cell densities of 10x104, 20x104, 40x10 4 and 80x104. Cell viability with WST and proliferation with Live-Dead cell assays

  9. MRI of transforaminal lumbar interbody fusion: imaging appearance with and without the use of human recombinant bone morphogenetic protein-2 (rhBMP-2)

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Michael G.; Goldberg, Judd M.; Gaskin, Cree M.; Barr, Michelle S.; Alford, Bennett [University of Virginia, Department of Radiology and Medical Imaging, Charlottesville, VA (United States); Patrie, James T. [University of Virginia, Department of Public Health Sciences, Charlottesville, VA (United States); Shen, Francis H. [University of Virginia, Department of Orthopedic Surgery, Charlottesville, VA (United States)

    2014-09-15

    To describe the vertebral endplate and intervertebral disc space MRI appearance following TLIF, with and without the use of rhBMP-2, and to determine if the appearance is concerning for discitis/osteomyelitis. After institutional review board approval, 116 TLIF assessments performed on 75 patients with rhBMP-2 were retrospectively and independently reviewed by five radiologists and compared to 73 TLIF assessments performed on 45 patients without rhBMP-2. MRIs were evaluated for endplate signal, disc space enhancement, disc space fluid, and abnormal paraspinal soft tissue. Endplate edema-like signal was reported when T1-weighted hypointensity, T2-weighted hyperintensity, and endplate enhancement were present. Subjective concern for discitis/osteomyelitis on MRI was graded on a five-point scale. Generalized estimating equation binomial regression model analysis was performed with findings correlated with rhBMP-2 use, TLIF level, graft type, and days between TLIF and MRI. The rhBMP-2 group demonstrated endplate edema-like signal (OR 5.66; 95 % CI [1.58, 20.24], p = 0.008) and disc space enhancement (OR 2.40; 95 % CI [1.20, 4.80], p = 0.013) more often after adjusting for the TLIF level, graft type, and the number of days following TLIF. Both groups had a similar temporal distribution for endplate edema-like signal but disc space enhancement peaked earlier in the rhBMP-2 group. Disc space fluid was only present in the rhBMP-2 group. Neither group demonstrated abnormal paraspinal soft tissue and discitis/osteomyelitis was not considered likely in any patient. Endplate edema-like signal and disc space enhancement were significantly more frequent and disc space enhancement developed more rapidly following TLIF when rhBMP-2 was utilized. The concern for discitis/osteomyelitis was similar and minimal in both groups. (orig.)

  10. Metastatic function of BMP-2 in gastric cancer cells: The role of PI3K/AKT, MAPK, the NF-{kappa}B pathway, and MMP-9 expression

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Myoung Hee [Graduate School of Medicine, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Oh, Sang Cheul [Division of Oncology/Hematology, Department of Internal Medicine, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Lee, Hyun Joo [Department of Pathology, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kang, Han Na; Kim, Jung Lim [Graduate School of Medicine, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Kim, Jun Suk [Division of Oncology/Hematology, Department of Internal Medicine, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of); Yoo, Young A., E-mail: ydanbi@korea.ac.kr [Brain Korea 21 Program for Biomedical Science, Korea University College of Medicine, Korea University, Seoul 136-705 (Korea, Republic of)

    2011-07-15

    Bone morphogenetic proteins (BMPs) have been implicated in tumorigenesis and metastatic progression in various types of cancer cells, but the role and cellular mechanism in the invasive phenotype of gastric cancer cells is not known. Herein, we determined the roles of phosphoinositide 3-kinase (PI3K)/AKT, extracellular signal-regulated protein kinase (ERK), nuclear factor (NF)-{kappa}B, and matrix metalloproteinase (MMP) expression in BMP-2-mediated metastatic function in gastric cancer. We found that stimulation of BMP-2 in gastric cancer cells enhanced the phosphorylation of AKT and ERK. Accompanying activation of AKT and ERK kinase, BMP-2 also enhanced phosphorylation/degradation of I{kappa}B{alpha} and the nuclear translocation/activation of NF-{kappa}B. Interestingly, blockade of PI3K/AKT and ERK signaling using LY294002 and PD98059, respectively, significantly inhibited BMP-2-induced motility and invasiveness in association with the activation of NF-{kappa}B. Furthermore, BMP-2-induced MMP-9 expression and enzymatic activity was also significantly blocked by treatment with PI3K/AKT, ERK, or NF-{kappa}B inhibitors. Immunohistochemistry staining of 178 gastric tumor biopsies indicated that expression of BMP-2 and MMP-9 had a significant positive correlation with lymph node metastasis and a poor prognosis. These results indicate that the BMP-2 signaling pathway enhances tumor metastasis in gastric cancer by sequential activation of the PI3K/AKT or MAPK pathway followed by the induction of NF-{kappa}B and MMP-9 activity, indicating that BMP-2 has the potential to be a therapeutic molecular target to decrease metastasis.

  11. Colloid, adhesive and release properties of nanoparticular ternary complexes between cationic and anionic polysaccharides and basic proteins like bone morphogenetic protein BMP-2.

    Science.gov (United States)

    Petzold, R; Vehlow, D; Urban, B; Grab, A L; Cavalcanti-Adam, E A; Alt, V; Müller, M

    2017-03-01

    Herein we describe an interfacial local drug delivery system for bone morphogenetic protein 2 (BMP-2) based on coatings of polyelectrolyte complex (PEC) nanoparticles (NP). The application horizon is the functionalization of bone substituting materials (BSM) used for the therapy of systemic bone diseases. Nanoparticular ternary complexes of cationic and anionic polysaccharides and BMP-2 or two further model proteins, respectively, were prepared in dependence of the molar mixing ratio, pH value and of the cationic polysaccharide. As further proteins chymotrypsin (CHY) and papain (PAP) were selected, which served as model proteins for BMP-2 due to similar isoelectric points and molecular weights. As charged polysaccharides ethylenediamine modified cellulose (EDAC) and trimethylammonium modified cellulose (PQ10) were combined with cellulose sulphatesulfate (CS). Mixing diluted cationic and anionic polysaccharide and protein solutions according to a slight either anionic or cationic excess charge colloidal ternary dispersions formed, which were cast onto germanium model substrates by water evaporation. Dynamic light scattering (DLS) demonstrated, that these dispersions were colloidally stable for at least one week. Fourier Transform Infrared (FTIR) showed, that the cast protein loaded PEC NP coatings were irreversibly adhesive at the model substrate in contact to HEPES buffer and solely CHY, PAP and BMP-2 were released within long-term time scale. Advantageously, out of the three proteins BMP-2 showed the smallest initial burst and the slowest release kinetics and around 25% of the initial BMP-2 content were released within 14days. Released BMP-2 showed significant activity in the myoblast cells indicating the ability to regulate the formation of new bone. Therefore, BMP-2 loaded PEC NP are suggested as novel promising tool for the functionalization of BSM used for the therapy of systemic bone diseases. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Medium-Term Function of a 3D Printed TCP/HA Structure as a New Osteoconductive Scaffold for Vertical Bone Augmentation: A Simulation by BMP-2 Activation

    Directory of Open Access Journals (Sweden)

    Mira Moussa

    2015-04-01

    Full Text Available Introduction: A 3D-printed construct made of orthogonally layered strands of tricalcium phosphate (TCP and hydroxyapatite has recently become available. The material provides excellent osteoconductivity. We simulated a medium-term experiment in a sheep calvarial model by priming the blocks with BMP-2. Vertical bone growth/maturation and material resorption were evaluated. Materials and methods: Titanium hemispherical caps were filled with either bare- or BMP-2 primed constructs and placed onto the calvaria of adult sheep (n = 8. Histomorphometry was performed after 8 and 16 weeks. Results: After 8 weeks, relative to bare constructs, BMP-2 stimulation led to a two-fold increase in bone volume (Bare: 22% ± 2.1%; BMP-2 primed: 50% ± 3% and a 3-fold decrease in substitute volume (Bare: 47% ± 5%; BMP-2 primed: 18% ± 2%. These rates were still observed at 16 weeks. The new bone grew and matured to a haversian-like structure while the substitute material resorbed via cell- and chemical-mediation. Conclusion: By priming the 3D construct with BMP-2, bone metabolism was physiologically accelerated, that is, enhancing vertical bone growth and maturation as well as material bioresorption. The scaffolding function of the block was maintained, leaving time for the bone to grow and mature to a haversian-like structure. In parallel, the material resorbed via cell-mediated and chemical processes. These promising results must be confirmed in clinical tests.

  13. Functionalization of deproteinized bovine bone with a coating-incorporated depot of BMP-2 renders the material efficiently osteoinductive and suppresses foreign-body reactivity.

    Science.gov (United States)

    Wu, Gang; Hunziker, Ernst B; Zheng, Yuanna; Wismeijer, Daniel; Liu, Yuelian

    2011-12-01

    The repair of critical-sized bony defects remains a challenge in the fields of implantology, maxillofacial surgery and orthopaedics. As an alternative bone-defect filler to autologous bone grafts, deproteinized bovine bone (DBB) is highly osteoconductive and clinically now widely used. However, this product suffers from the disadvantage of not being intrinsically osteoinductive. In the present study, this property was conferred by coating DBB with a layer of calcium phosphate into which bone morphogenetic protein 2 (BMP-2) was incorporated. Granules of DBB bearing a coating-incorporated depot of BMP-2--together with the appropriate controls (DBB bearing a coating but no BMP-2; uncoated DBB bearing adsorbed BMP-2; uncoated DBB bearing no BMP-2)--were implanted subcutaneously in rats. Five weeks later, the implants were withdrawn for a histomorphometric analysis of the volume densities of (i) bone, (ii) bone marrow, (iii) foreign-body giant cells and (iv) fibrous capsular tissue. Parameters (i) and (ii) were highest, whilst parameters (iii) and (iv) were lowest in association with DBB bearing a coating-incorporated depot of BMP-2. Hence, this mode of functionalization not only confers DBB with the property of osteoinductivity but also improves its biocompatibility--thus dually enhancing its clinical potential in the repair of bony defects. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Adipose-derived stem cells and BMP-2 delivery in chitosan-based 3D constructs to enhance bone regeneration in a rat mandibular defect model.

    Science.gov (United States)

    Fan, Jiabing; Park, Hyejin; Lee, Matthew K; Bezouglaia, Olga; Fartash, Armita; Kim, Jinku; Aghaloo, Tara; Lee, Min

    2014-08-01

    Reconstructing segmental mandiblular defects remains a challenge in the clinic. Tissue engineering strategies provide an alternative option to resolve this problem. The objective of the present study was to determine the effects of adipose-derived stem cells (ASCs) and bone morphogenetic proteins-2 (BMP-2) in three-dimensional (3D) scaffolds on mandibular repair in a small animal model. Noggin expression levels in ASCs were downregulated by a lentiviral short hairpin RNA strategy to enhance ASC osteogenesis (ASCs(Nog-)). Chitosan (CH) and chondroitin sulfate (CS), natural polysaccharides, were fabricated into 3D porous scaffolds, which were further modified with apatite coatings for enhanced cellular responses and efficient delivery of BMP-2. The efficacy of 3D apatite-coated CH/CS scaffolds supplemented with ASCs(Nog-) and BMP-2 were evaluated in a rat critical-sized mandibular defect model. After 8 weeks postimplantation, the scaffolds treated with ASCs(Nog-) and BMP-2 significantly promoted rat mandibular regeneration as demonstrated by micro-computerized tomography, histology, and immunohistochemistry, compared with the groups treated with ASCs(Nog-) or BMP-2 alone. These results suggest that our combinatorial strategy of ASCs(Nog-)+BMP-2 in 3D apatite microenvironments can significantly promote mandibular regeneration, and these may provide a potential tissue engineering approach to repair large bony defects.

  15. A Novel Human TGF-β1 Fusion Protein in Combination with rhBMP-2 Increases Chondro-Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells

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    Silvia Claros

    2014-06-01

    Full Text Available Transforming growth factor-beta (TGF-β is involved in processes related to the differentiation and maturation of osteoprogenitor cells into osteoblasts. Rat bone marrow (BM cells were cultured in a collagen-gel containing 0.5% fetal bovine serum (FBS for 10 days in the presence of rhTGF (recombinant human TGF-β1-F2, a fusion protein engineered to include a high-affinity collagen-binding decapeptide derived from von Willebrand factor. Subsequently, cells were moderately expanded in medium with 10% FBS for 4 days and treated with a short pulse of rhBMP (recombinant human bone morphogenetic protein-2 for 4 h. During the last 2 days, dexamethasone and β-glycerophosphate were added to potentiate osteoinduction. Concomitant with an up-regulation of cell proliferation, DNA synthesis levels were determined. Polymerase chain reaction was performed to reveal the possible stemness of these cells. Osteogenic differentiation was evaluated in terms of alkaline phosphatase activity and mineralized matrix formation as well as by mRNA expression of osteogenic marker genes. Moreover, cells were placed inside diffusion chambers and implanted subcutaneously into the backs of adult rats for 4 weeks. Histological study provided evidence of cartilage and bone-like tissue formation. This experimental procedure is capable of selecting cell populations from BM that, in the presence of rhTGF-β1-F2 and rhBMP-2, achieve skeletogenic potential in vitro and in vivo.

  16. Differential gene expression profiling of human adipose stem cells differentiating into smooth muscle-like cells by TGFβ1/BMP4

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    Elçin, Ayşe Eser; Parmaksiz, Mahmut; Dogan, Arin; Seker, Sukran; Durkut, Serap; Dalva, Klara; Elçin, Yaşar Murat, E-mail: elcinmurat@gmail.com

    2017-03-15

    Regenerative repair of the vascular system is challenging from the perspectives of translational medicine and tissue engineering. There are fundamental hurdles in front of creating bioartificial arteries, which involve recaputilation of the three-layered structure under laboratory settings. Obtaining and maintaining smooth muscle characteristics is an important limitation, as the transdifferentiated cells fail to display mature phenotype. This study aims to shed light on the smooth muscle differentiation of human adipose stem cells (hASCs). To this end, we first acquired hASCs from lipoaspirate samples. Upon characterization, the cells were induced to differentiate into smooth muscle (SM)-like cells using a variety of inducer combinations. Among all, TGFβ1/BMP4 combination had the highest differentiation efficiency, based on immunohistochemical analyses. hSM-like cell samples were compared to hASCs and to the positive control, human coronary artery-smooth muscle cells (hCA-SMCs) through gene transcription profiling. Microarray findings revealed the activation of gene groups that function in smooth muscle differentiation, signaling pathways, extracellular modeling and cell proliferation. Our results underline the effectiveness of the growth factors and suggest some potential variables for detecting the SM-like cell characteristics. Evidence in transcriptome level was used to evaluate the TGFβ1/BMP4 combination as a previously unexplored effector for the smooth muscle differentiation of adipose stem cells. - Highlights: • Human adipose stem cells (hASCs) were isolated, characterized and cultured. • Growth factor combinations were evaluated for their effectiveness in differentiation using IHC. • hASCs were differentiated into smooth muscle (SM)-like cells using TGF-β1 and BMP4 combination. • Microarray analysis was performed for hASCs, SM-like cells and coronary artery-SMCs. • Microarray data was used to perform hierarchical clustering and interpretation

  17. A SHH-FOXF1-BMP4 signaling axis regulating growth and differentiation of epithelial and mesenchymal tissues in ureter development.

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    Tobias Bohnenpoll

    2017-08-01

    Full Text Available The differentiated cell types of the epithelial and mesenchymal tissue compartments of the mature ureter of the mouse arise in a precise temporal and spatial sequence from uncommitted precursor cells of the distal ureteric bud epithelium and its surrounding mesenchyme. Previous genetic efforts identified a member of the Hedgehog (HH family of secreted proteins, Sonic hedgehog (SHH as a crucial epithelial signal for growth and differentiation of the ureteric mesenchyme. Here, we used conditional loss- and gain-of-function experiments of the unique HH signal transducer Smoothened (SMO to further characterize the cellular functions and unravel the effector genes of HH signaling in ureter development. We showed that HH signaling is not only required for proliferation and SMC differentiation of cells of the inner mesenchymal region but also for survival of cells of the outer mesenchymal region, and for epithelial proliferation and differentiation. We identified the Forkhead transcription factor gene Foxf1 as a target of HH signaling in the ureteric mesenchyme. Expression of a repressor version of FOXF1 in this tissue completely recapitulated the mesenchymal and epithelial proliferation and differentiation defects associated with loss of HH signaling while re-expression of a wildtype version of FOXF1 in the inner mesenchymal layer restored these cellular programs when HH signaling was inhibited. We further showed that expression of Bmp4 in the ureteric mesenchyme depends on HH signaling and Foxf1, and that exogenous BMP4 rescued cell proliferation and epithelial differentiation in ureters with abrogated HH signaling or FOXF1 function. We conclude that SHH uses a FOXF1-BMP4 module to coordinate the cellular programs for ureter elongation and differentiation, and suggest that deregulation of this signaling axis occurs in human congenital anomalies of the kidney and urinary tract (CAKUT.

  18. A SHH-FOXF1-BMP4 signaling axis regulating growth and differentiation of epithelial and mesenchymal tissues in ureter development.

    Science.gov (United States)

    Bohnenpoll, Tobias; Wittern, Anna B; Mamo, Tamrat M; Weiss, Anna-Carina; Rudat, Carsten; Kleppa, Marc-Jens; Schuster-Gossler, Karin; Wojahn, Irina; Lüdtke, Timo H-W; Trowe, Mark-Oliver; Kispert, Andreas

    2017-08-01

    The differentiated cell types of the epithelial and mesenchymal tissue compartments of the mature ureter of the mouse arise in a precise temporal and spatial sequence from uncommitted precursor cells of the distal ureteric bud epithelium and its surrounding mesenchyme. Previous genetic efforts identified a member of the Hedgehog (HH) family of secreted proteins, Sonic hedgehog (SHH) as a crucial epithelial signal for growth and differentiation of the ureteric mesenchyme. Here, we used conditional loss- and gain-of-function experiments of the unique HH signal transducer Smoothened (SMO) to further characterize the cellular functions and unravel the effector genes of HH signaling in ureter development. We showed that HH signaling is not only required for proliferation and SMC differentiation of cells of the inner mesenchymal region but also for survival of cells of the outer mesenchymal region, and for epithelial proliferation and differentiation. We identified the Forkhead transcription factor gene Foxf1 as a target of HH signaling in the ureteric mesenchyme. Expression of a repressor version of FOXF1 in this tissue completely recapitulated the mesenchymal and epithelial proliferation and differentiation defects associated with loss of HH signaling while re-expression of a wildtype version of FOXF1 in the inner mesenchymal layer restored these cellular programs when HH signaling was inhibited. We further showed that expression of Bmp4 in the ureteric mesenchyme depends on HH signaling and Foxf1, and that exogenous BMP4 rescued cell proliferation and epithelial differentiation in ureters with abrogated HH signaling or FOXF1 function. We conclude that SHH uses a FOXF1-BMP4 module to coordinate the cellular programs for ureter elongation and differentiation, and suggest that deregulation of this signaling axis occurs in human congenital anomalies of the kidney and urinary tract (CAKUT).

  19. Trehalose maintains bioactivity and promotes sustained release of BMP-2 from lyophilized CDHA scaffolds for enhanced osteogenesis in vitro and in vivo.

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    Jun Zhao

    Full Text Available Calcium phosphate (Ca-P scaffolds have been widely employed as a supportive matrix and delivery system for bone tissue engineering. Previous studies using osteoinductive growth factors loaded Ca-P scaffolds via passive adsorption often experience issues associated with easy inactivation and uncontrolled release. In present study, a new delivery system was fabricated using bone morphogenetic protein-2 (BMP-2 loaded calcium-deficient hydroxyapatite (CDHA scaffold by lyophilization with addition of trehalose. The in vitro osteogenesis effects of this formulation were compared with lyophilized BMP-2/CDHA construct without trehalose and absorbed BMP-2/CDHA constructs with or without trehalose. The release characteristics and alkaline phosphatase (ALP activity analyses showed that addition of trehalose could sufficiently protect BMP-2 bioactivity during lyophilization and achieve sustained BMP-2 release from lyophilized CDHA construct in vitro and in vivo. However, absorbed BMP-2/CDHA constructs with or without trehalose showed similar BMP-2 bioactivity and presented a burst release. Quantitative real-time PCR (RT-qPCR and enzyme-linked immunosorbent assay (ELISA demonstrated that lyophilized BMP-2/CDHA construct with trehalose (lyo-tre-BMP-2 promoted osteogenic differentiation of bone marrow stromal cells (bMSCs significantly and this formulation could preserve over 70% protein bioactivity after 5 weeks storage at 25°C. Micro-computed tomography, histological and fluorescent labeling analyses further demonstrated that lyo-tre-BMP-2 formulation combined with bMSCs led to the most percentage of new bone volume (38.79% ± 5.32% and area (40.71% ± 7.14% as well as the most percentage of fluorochrome stained bone area (alizarin red S: 2.64% ± 0.44%, calcein: 6.08% ± 1.37% and mineral apposition rate (4.13 ± 0.62 µm/day in critical-sized rat cranial defects healing. Biomechanical tests also indicated the maximum stiffness (118.17 ± 15.02 Mpa and

  20. Deproteinized bovine bone functionalized with the slow delivery of BMP-2 for the repair of critical-sized bone defects in sheep.

    Science.gov (United States)

    Liu, Tie; Wu, Gang; Wismeijer, Daniel; Gu, Zhiyuan; Liu, Yuelian

    2013-09-01

    As an alternative to an autologous bone graft, deproteinized bovine bone (DBB) is widely used in the clinical dentistry. Although DBB provides an osteoconductive scaffold, it is not capable of enhancing bone regeneration because it is not osteoinductive. In order to render DBB osteoinductive, bone morphogenetic protein 2 (BMP-2) has previously been incorporated into a three dimensional reservoir (a biomimetic calcium phosphate coating) on DBB, which effectively promoted the osteogenic response by the slow delivery of BMP-2. The aim of this study was to investigate the therapeutic effectiveness of such coating on the DBB granules in repairing a large cylindrical bone defect (8 mm diameter, 13 mm depth) in sheep. Eight groups were randomly assigned to the bone defects: (i) no graft material; (ii) autologous bone; (iii) DBB only; (iv) DBB mixed with autologous bone; (v) DBB bearing adsorbed BMP-2; (vi) DBB bearing a coating but no BMP-2; (vii) DBB bearing a coating with adsorbed BMP-2; and (viii) DBB bearing a coating-incorporated depot of BMP-2. 4 and 8 weeks after implantation, samples were withdrawn for a histological and a histomorphometric analysis. Histological results confirmed the excellent biocompatibility and osteoconductivity of all the grafts tested. At 4 weeks, DBB mixed with autologous bone or functionalized with coating-incorporated BMP-2 showed more newly-formed bone than the other groups with DBB. At 8 weeks, the volume of newly-formed bone around DBB that bore a coating-incorporated depot of BMP-2 was greatest among the groups with DBB, and was comparable to the autologous bone group. The use of autologous bone and BMP-2 resulted in more bone marrow formation. Multinucleated giant cells were observed in the resorption process around DBB, whereas histomorphometric analysis revealed no significant degradation of DBB. In conclusion, it was shown that incorporating BMP-2 into the calcium phosphate coating of DBB induced strong bone formation around DBB

  1. Evaluation of bioactive glass incorporated poly(caprolactone)-poly(vinyl alcohol) matrix and the effect of BMP-2 modification

    Energy Technology Data Exchange (ETDEWEB)

    Keothongkham, Khamsone [Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Charoenphandhu, Narattaphol [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok 10900 (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok 10900 (Thailand); Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170 (Thailand); Thongbunchoo, Jirawan; Suntornsaratoon, Panan; Krishnamra, Nateetip [Center of Calcium and Bone Research (COCAB), Faculty of Science, Mahidol University, Bangkok 10900 (Thailand); Department of Physiology, Faculty of Science, Mahidol University, Bangkok 10900 (Thailand); Tang, I-Ming [Department of Materials Science Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand); Pon-On, Weeraphat, E-mail: fsciwpp@ku.ac.th [Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900 (Thailand)

    2017-05-01

    Composite materials having mechanical and biological properties similar to those of human bones are needed for bone regeneration and repair. In the present study, composites were made by incorporating bioactive glass (BG) into polycaprolactone (PCL)-polyvinyl alcohol (PVA) (PCLPVA) matrix. Composites with different BG contents of 10, 25 and 50 wt% were fabricated by an in-situ blending method. Physicochemical properties measurements found that the composite with 50 wt% BG in the PCLPVA organic matrix exhibited the best mechanical properties (compressive strength and compressive young's modulus up to 32.26 MPa and 530.91 MPa, respectively). We investigated the effects of the BG content on cell adhesion, proliferation and osteogenic activity of UMR-106 cells grown on the scaffolds using in vitro cell culture assay. The composite scaffolds having 25 wt% BG showed a significant increase in their cell adhesion capability and a faster cell proliferation. They also exhibited cell adhesion and spreading morphology after only 5 days of culturing. For these reasons, we chose to attach the bone morphogenetic protein (BMP)-2 to this composite. The resulting composite (labeled BMP-2-loaded PCLPVABG25) showed significant improvement in the UMR-106 cells adhesion, in the enhancement in osteogenic differentiation and osteoinductivity of this composite. - Highlights: • Preparation of PCLPVABGx composite scaffolds and their physical properties. • Mechanical properties could be adjusted by controlling BG contents in PCLPVA matrix. • In vitro cell availability tests confirmed the osteoblast grow on the PCLPVABGx composite scaffolds surface. • Upon the BMP-2-loaded PCLPVABG25 scaffolds can enhance cell attachment and significantly improved osteogenicity.

  2. Controlled Retention of BMP-2-Derived Peptide on Nanofibers Based on Mussel-Inspired Adhesion for Bone Formation.

    Science.gov (United States)

    Lee, Jinkyu; Perikamana, Sajeesh Kumar Madhurakkat; Ahmad, Taufiq; Lee, Min Suk; Yang, Hee Seok; Kim, Do-Gyoon; Kim, Kyobum; Kwon, Bosun; Shin, Heungsoo

    2017-04-01

    Although bone morphogenetic protein-2 (BMP-2) has been frequently used to stimulate bone formation, it has several side effects to be addressed, including the difficulty in optimization of clinically relevant doses and unwanted induction of cancerous signaling processes. In this study, an osteogenic peptide (OP) derived from BMP-2 was investigated as a substitute for BMP-2. In vitro studies showed that OP was able to enhance the osteogenic differentiation and mineralization of human mesenchymal stem cells (hMSCs). The peptides were then conjugated onto biocompatible poly-ι-lactide electrospun nanofibers through polydopamine chemistry. Surface chemical analysis proved that more than 80% of the peptides were stably retained on the nanofiber surface after 8 h of polydopamine coating during at least 28 days, and the amount of peptides that was retained increased depending on the polydopamine coating time. For instance, about 65% of the peptides were retained on nanofibers after 4 h of polydopamine coating. Also, a relatively small dose of peptides could effectively induce bone formation in in vivo critical-sized defects on the calvarial bones of mice. More than 50.4% ± 16.9% of newly formed bone was filled within the defect after treatment with only 10.5 ± 0.6 μg of peptides. Moreover, these groups had similar elastic moduli and contact hardnesses with host bone. Taken together, our results suggest that polydopamine-mediated OP immobilized on nanofibers can modulate the retention of relatively short lengths of peptides, which might make this an effective therapeutic remedy to guide bone regeneration using a relatively small amount of peptides.

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

    Science.gov (United States)

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

    2017-01-01

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

  4. Enhancement of Tendon–Bone Healing for Anterior Cruciate Ligament (ACL Reconstruction Using Bone Marrow-Derived Mesenchymal Stem Cells Infected with BMP-2

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    Shiyi Chen

    2012-10-01

    Full Text Available At present, due to the growing attention focused on the issue of tendon–bone healing, we carried out an animal study of the use of genetic intervention combined with cell transplantation for the promotion of this process. Here, the efficacy of bone marrow stromal cells infected with bone morphogenetic protein-2 (BMP-2 on tendon–bone healing was determined. A eukaryotic expression vector containing the BMP-2 gene was constructed and bone marrow-derived mesenchymal stem cells (bMSCs were infected with a lentivirus. Next, we examined the viability of the infected cells and the mRNA and protein levels of BMP-2-infected bMSCs. Gastrocnemius tendons, gastrocnemius tendons wrapped by bMSCs infected with the control virus (bMSCs+Lv-Control, and gastrocnemius tendons wrapped by bMSCs infected with the recombinant BMP-2 virus (bMSCs+Lv-BMP-2 were used to reconstruct the anterior cruciate ligament (ACL in New Zealand white rabbits. Specimens from each group were harvested four and eight weeks postoperatively and evaluated using biomechanical and histological methods. The bMSCs were infected with the lentivirus at an efficiency close to 100%. The BMP-2 mRNA and protein levels in bMSCs were significantly increased after lentiviral infection. The bMSCs and BMP-2-infected bMSCs on the gastrocnemius tendon improved the biomechanical properties of the graft in the bone tunnel; specifically, bMSCs infected with BMP-2 had a positive effect on tendon–bone healing. In the four-week and eight-week groups, bMSCs+Lv-BMP-2 group exhibited significantly higher maximum loads of 29.3 ± 7.4 N and 45.5 ± 11.9 N, respectively, compared with the control group (19.9 ± 6.4 N and 21.9 ± 4.9 N (P = 0.041 and P = 0.001, respectively. In the eight-week groups, the stiffness of the bMSCs+Lv-BMP-2 group (32.5 ± 7.3 was significantly higher than that of the bMSCs+Lv-Control group (22.8 ± 7.4 or control groups (12.4 ± 6.0 (p = 0.036 and 0.001, respectively. Based on the

  5. Noggin and BMP4 co-modulate adult hippocampal neurogenesis in the APP{sub swe}/PS1{sub {Delta}E9} transgenic mouse model of Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Jun [Department of Medical Genetics, Third Military Medical University, Chongqing 400038 (China); Department of Physiology, Third Military Medical University, Chongqing 400038 (China); Song, Min; Wang, Yanyan [Department of Medical Genetics, Third Military Medical University, Chongqing 400038 (China); Fan, Xiaotang [Department of Histology and Embryology, Third Military Medical University, Chongqing 400038 (China); Xu, Haiwei, E-mail: haiweixu2001@yahoo.com.cn [Department of Physiology, Third Military Medical University, Chongqing 400038 (China); Bai, Yun, E-mail: baiyungene@gmail.com [Department of Medical Genetics, Third Military Medical University, Chongqing 400038 (China)

    2009-07-31

    In addition to the subventricular zone, the dentate gyrus of the hippocampus is one of the few brain regions in which neurogenesis continues into adulthood. Perturbation of neurogenesis can alter hippocampal function, and previous studies have shown that neurogenesis is dysregulated in Alzheimer disease (AD) brain. Bone morphogenetic protein-4 (BMP4) and its antagonist Noggin have been shown to play important roles both in embryonic development and in the adult nervous system, and may regulate hippocampal neurogenesis. Previous data indicated that increased expression of BMP4 mRNA within the dentate gyrus might contribute to decreased hippocampal cell proliferation in the APP{sub swe}/PS1{sub {Delta}E9} mouse AD model. However, it is not known whether the BMP antagonist Noggin contributes to the regulation of neurogenesis. We therefore studied the relative expression levels and localization of BMP4 and its antagonist Noggin in the dentate gyrus and whether these correlated with changes in neurogenesis in 6-12 mo old APP{sub swe}/PS1{sub {Delta}E9} transgenic mice. Bromodeoxyuridine (BrdU) was used to label proliferative cells. We report that decreased neurogenesis in the APP/PS1 transgenic mice was accompanied by increased expression of BMP4 and decreased expression of Noggin at both the mRNA and protein levels; statistical analysis showed that the number of proliferative cells at different ages correlated positively with Noggin expression and negatively with BMP4 expression. Intraventricular administration of a chimeric Noggin/Fc protein was used to block the action of endogenous BMP4; this resulted in a significant increase in the number of BrdU-labeled cells in dentate gyrus subgranular zone and hilus in APP/PS1 mice. These results suggest that BMP4 and Noggin co-modulate neurogenesis.

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

    Science.gov (United States)

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

    2011-01-01

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

  7. Bone induction through controlled release of novel BMP-2-related peptide from PTMC11-F127-PTMC11 hydrogels

    International Nuclear Information System (INIS)

    Tang Shuo; Li Jingfeng; Teng Yu; Guo Xiaodong; Zhao Jingjing; Xu Shuyun; Quan Daping

    2012-01-01

    Bone morphogenetic protein 2 (BMP-2) is the most powerful osteogenic factor; its effectiveness in enhancing osteoblastic activation has been confirmed both in vitro and in vivo. We developed a novel peptide (designated P24) derived from the ‘knuckle’ epitope of BMP-2 and found it also had osteogenic bioactivity to some extent. The main objective of this study was to develop a controlled release system based on poly(trimethylene carbonate)–F127–poly(trimethylene carbonate) (PTMC 11 -F127-PTMC 11 ) hydrogels for the P24 peptide, to promote bone formation. By varying the copolymer concentrations, we demonstrated that P24/PTMC 11 -F127-PTMC 11 hydrogels were an efficient system for the sustained release of P24 over 21–35 days. The P24-loaded hydrogels elevated alkaline phosphatase activity and promoted the expression of osteocalcin mRNA in bone marrow stromal cells (BMSCs) in vitro. Radiographic and histological examination showed that P24-loaded hydrogels could induce more effective ectopic bone formation in vivo than P24-free hydrogels. These results indicate that the PTMC 11 -F127-PTMC 11 hydrogel is a suitable carrier for the controlled release of P24, and is a promising injectable biomaterial for the induction of bone regeneration. (paper)

  8. Gelatin Tight-Coated Poly(lactide-co-glycolide Scaffold Incorporating rhBMP-2 for Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Juan Wang

    2015-03-01

    Full Text Available Surface coating is the simplest surface modification. However, bioactive molecules can not spread well on the commonly used polylactone-type skeletons; thus, the surface coatings of biomolecules are typically unstable due to the weak interaction between the polymer and the bioactive molecules. In this study, a special type of poly(lactide-co-glycolide (PLGA-based scaffold with a loosened skeleton was fabricated by phase separation, which allowed gelatin molecules to more readily diffuse throughout the structure. In this application, gelatin modified both the internal substrate and external surface. After cross-linking with glutaraldehyde, the surface layer gelatin was tightly bound to the diffused gelatin, thereby preventing the surface layer gelatin coating from falling off within 14 days. After gelatin modification, PLGA scaffold demonstrated enhanced hydrophilicity and improved mechanical properties (i.e., increased compression strength and elastic modulus in dry and wet states. Furthermore, a sustained release profile of recombinant human bone morphogenetic protein-2 (rhBMP-2 was achieved in the coated scaffold. The coated scaffold also supported the in vitro attachment, proliferation, and osteogenesis of rabbit bone mesenchymal stem cells (BMSCs, indicating the bioactivity of rhBMP-2. These results collectively demonstrate that the cross-linked-gelatin-coated porous PLGA scaffold incorporating bioactive molecules is a promising candidate for bone tissue regeneration.

  9. Cardiogenic induction of pluripotent stem cells streamlined through a conserved SDF-1/VEGF/BMP2 integrated network.

    Directory of Open Access Journals (Sweden)

    Anca Chiriac

    Full Text Available BACKGROUND: Pluripotent stem cells produce tissue-specific lineages through programmed acquisition of sequential gene expression patterns that function as a blueprint for organ formation. As embryonic stem cells respond concomitantly to diverse signaling pathways during differentiation, extraction of a pro-cardiogenic network would offer a roadmap to streamline cardiac progenitor output. METHODS AND RESULTS: To resolve gene ontology priorities within precursor transcriptomes, cardiogenic subpopulations were here generated according to either growth factor guidance or stage-specific biomarker sorting. Innate expression profiles were independently delineated through unbiased systems biology mapping, and cross-referenced to filter transcriptional noise unmasking a conserved progenitor motif (55 up- and 233 down-regulated genes. The streamlined pool of 288 genes organized into a core biological network that prioritized the "Cardiovascular Development" function. Recursive in silico deconvolution of the cardiogenic neighborhood and associated canonical signaling pathways identified a combination of integrated axes, CXCR4/SDF-1, Flk-1/VEGF and BMP2r/BMP2, predicted to synchronize cardiac specification. In vitro targeting of the resolved triad in embryoid bodies accelerated expression of Nkx2.5, Mef2C and cardiac-MHC, enhanced beating activity, and augmented cardiogenic yield. CONCLUSIONS: Transcriptome-wide dissection of a conserved progenitor profile thus revealed functional highways that coordinate cardiogenic maturation from a pluripotent ground state. Validating the bioinformatics algorithm established a strategy to rationally modulate cell fate, and optimize stem cell-derived cardiogenesis.

  10. * Calvarial Bone Regeneration Is Enhanced by Sequential Delivery of FGF-2 and BMP-2 from Layer-by-Layer Coatings with a Biomimetic Calcium Phosphate Barrier Layer.

    Science.gov (United States)

    Gronowicz, Gloria; Jacobs, Emily; Peng, Tao; Zhu, Li; Hurley, Marja; Kuhn, Liisa T

    2017-12-01

    A drug delivery coating for synthetic bone grafts has been developed to provide sequential delivery of multiple osteoinductive factors to better mimic aspects of the natural regenerative process. The coating is composed of a biomimetic calcium phosphate (bCaP) layer that is applied to a synthetic bone graft and then covered with a poly-l-Lysine/poly-l-Glutamic acid polyelectrolyte multilayer (PEM) film. Bone morphogenetic protein-2 (BMP-2) was applied before the coating process directly on the synthetic bone graft and then, bCaP-PEM was deposited followed by adsorption of fibroblast growth factor-2 (FGF-2) into the PEM layer. Cells access the FGF-2 immediately, while the bCaP-PEM temporally delays the cell access to BMP-2. In vitro studies with cells derived from mouse calvarial bones demonstrated that Sca-1 and CD-166 positive osteoblast progenitor cells proliferated in response to media dosing with FGF-2. Coated scaffolds with BMP-2 and FGF-2 were implanted in mouse calvarial bone defects and harvested at 1 and 3 weeks. After 1 week in vivo, proliferation of cells, including Sca-1+ progenitors, was observed with low dose FGF-2 and BMP-2 compared to BMP-2 alone, indicating that in vivo delivery of FGF-2 activated a similar population of cells as shown by in vitro testing. At 3 weeks, FGF-2 and BMP-2 delivery increased bone formation more than BMP-2 alone, particularly in the center of the defect, confirming that the proliferation of the Sca-1 positive osteoprogenitors by FGF-2 was associated with increased bone healing. Areas of bone mineralization were positive for double fluorochrome labeling of calcium and alkaline phosphatase staining of osteoblasts, along with increased TRAP+ osteoclasts, demonstrating active bone formation distinct from the bone-like collagen/hydroxyapatite scaffold. In conclusion, the addition of a bCaP layer to PEM delayed access to BMP-2 and allowed the FGF-2 stimulated progenitors to populate the scaffold before differentiating in

  11. Low-dose rhBMP2/7 heterodimer to reconstruct peri-implant bone defects: a micro-CT evaluation.

    Science.gov (United States)

    Wang, Jingxiao; Zheng, Yuanna; Zhao, Juan; Liu, Tie; Gao, Lixia; Gu, Zhiyuan; Wu, Gang

    2012-01-01

    To delineate the dynamic micro-architectures of bone induced by low-dose bone morphogenetic protein (BMP)-2/7 heterodimer in peri-implant bone defects compared to BMP2 and BMP7 homodimer. Peri-implant bone defects (8 mm in diameter, 4 mm in depth) were created surrounding SLA-treated titanium implants (3.1 mm in diameter, 10 mm in length) in minipig's calvaria. We administrated collagen sponges with adsorbed low-dose (30 ng/mm(3) ) BMP2/7 to treat the defects using BMP2, BMP7 or no BMP as controls.2, 3 and 6 weeks after implantation, we adopted micro-computer tomography to evaluate the micro-architectures of new bone using the following parameters: relative bone volume (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), connectivity density, and structure mode index (SMI). Bone implant contact (BIC) was also revealed histologically. Consistent with 2 and 3 weeks, after 6 weeks post-operation, BMP2/7 resulted in significantly higher BV/TV (63.033 ± 2.055%) and significantly lower SMI (-4.405 ± 0.500) than BMP2 (BV/TV: 43.133 ± 2.001%; SMI: -0.086 ± 0.041) and BMP7 (BV/TV: 41.467 ± 1.850%; SMI: -0.044 ± 0.016) respectively. Significant differences were also found in Tb.N, Tb.Th and Tb.Sp at all time points. At 2 weeks, BMP2/7 resulted in significantly higher BIC than the controls. Low-dose BMP2/7 heterodimer facilitated more rapid bone regeneration in better quality in peri-implant bone defects than BMP2 and BMP7 homodimers. © 2011 John Wiley & Sons A/S.

  12. Combination of BMP-2-releasing gelatin/β-TCP sponges with autologous bone marrow for bone regeneration of X-ray-irradiated rabbit ulnar defects.

    Science.gov (United States)

    Yamamoto, Masaya; Hokugo, Akishige; Takahashi, Yoshitake; Nakano, Takayoshi; Hiraoka, Masahiro; Tabata, Yasuhiko

    2015-07-01

    The objective of this study is to evaluate the feasibility of gelatin sponges incorporating β-tricalcium phosphate (β-TCP) granules (gelatin/β-TCP sponges) to enhance bone regeneration at a segmental ulnar defect of rabbits with X-ray irradiation. After X-ray irradiation of the ulnar bone, segmental critical-sized defects of 20-mm length were created, and bone morphogenetic protein-2 (BMP-2)-releasing gelatin/β-TCP sponges with or without autologous bone marrow were applied to the defects to evaluate bone regeneration. Both gelatin/β-TCP sponges containing autologous bone marrow and BMP-2-releasing sponges enhanced bone regeneration at the ulna defect to a significantly greater extent than the empty sponges (control). However, in the X-ray-irradiated bone, the bone regeneration either by autologous bone marrow or BMP-2 was inhibited. When combined with autologous bone marrow, the BMP-2 exhibited significantly high osteoinductivity, irrespective of the X-ray irradiation. The bone mineral content at the ulna defect was similar to that of the intact bone. It is concluded that the combination of bone marrow with the BMP-2-releasing gelatin/β-TCP sponge is a promising technique to induce bone regeneration at segmental bone defects after X-ray irradiation. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    Eğri, Sinan; Eczacıoğlu, Numan

    2017-03-01

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

  14. Curcumin induces osteoblast differentiation through mild-endoplasmic reticulum stress-mediated such as BMP2 on osteoblast cells.

    Science.gov (United States)

    Son, Hyo-Eun; Kim, Eun-Jung; Jang, Won-Gu

    2018-01-15

    Curcumin (diferuloylmethane or [1E,6E]-1,7-bis[4-hydroxy-3-methoxyphenyl]-1,6heptadiene-3,5-dione) is a phenolic natural product derived from the rhizomes of the turmeric plant, Curcuma longa. It is reported to have various biological actions such as anti-oxidative, anti-inflammatory, and anti-cancer effects. However, the molecular mechanism of osteoblast differentiation by curcumin has not yet been reported. The cytotoxicity of curcumin was identified using the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Expression of osteogenic markers and endoplasmic reticulum (ER) stress markers in C3H1-T1/2 cells were measured using reverse-transcriptase polymerase chain reaction (RT-PCR) and Western blotting. Alkaline phosphatase (ALP) staining was performed to assess ALP activity in C3H10T1/2 cells. Transcriptional activity was detected using a luciferase reporter assay. Curcumin increased the expression of genes such as distal-less homeobox 5 (Dlx5), runt-related transcription factor 2 (Runx2), ALP, and osteocalcin (OC), which subsequently induced osteoblast differentiation in C3H10T1/2 cells. In addition, ALP activity and mineralization was found to be increased by curcumin treatment. Curcumin also induced mild ER stress similar to bone morphogenetic protein 2 (BMP2) function in osteoblast cells. Next, we confirmed that curcumin increased mild ER stress and osteoblast differentiation similar to BMP2 in C3H10T1/2 mesenchymal stem cells. Transient transfection studies also showed that curcumin increased ATF6-Luc activity, while decreasing the activities of CREBH-Luc and SMILE-Luc. In addition, similar to BMP2, curcumin induced the phosphorylation of Smad 1/5/9. Overall, these results demonstrate that curcumin-induced mild ER stress increases osteoblast differentiation via ATF6 expression in C3H10T1/2 cells. Copyright © 2017. Published by Elsevier Inc.

  15. Three-Dimensional Cone Beam Computed Tomography Volumetric Outcomes of rhBMP-2/Demineralized Bone Matrix versus Iliac Crest Bone Graft for Alveolar Cleft Reconstruction.

    Science.gov (United States)

    Liang, Fan; Yen, Stephen L-K; Imahiyerobo, Thomas; Sanborn, Luke; Yen, Leia; Yen, Daniel; Nazarian, Sheila; Jedrzejewski, Breanna; Urata, Mark; Hammoudeh, Jeffrey

    2017-10-01

    Recent studies indicate that recombinant human bone morphogenetic protein-2 (rhBMP-2) in a demineralized bone matrix scaffold is a comparable alternative to iliac bone autograft in the setting of secondary alveolar cleft repair. Postreconstruction occlusal radiographs demonstrate improved bone stock when rhBMP-2/demineralized bone matrix (DBM) scaffold is used but lack the capacity to evaluate bone growth in three dimensions. This study uses cone beam computed tomography to provide the first clinical evaluation of volumetric and density comparisons between these two treatment modalities. A prospective study was conducted with 31 patients and 36 repairs of the alveolar cleft over a 2-year period. Twenty-one repairs used rhBMP-2/DBM scaffold and 14 repairs used iliac bone grafting. Postoperatively, occlusal radiographs were obtained at 3 months to evaluate bone fill; cone beam computed tomographic images were obtained at 6 to 9 months to compare volumetric and density data. At 3 months, postoperative occlusal radiographs demonstrated that 67 percent of patients receiving rhBMP-2/DBM scaffold had complete bone fill of the alveolus, versus 56 percent of patients in the autologous group. In contrast, cone beam computed tomographic data showed 31.6 percent (95 percent CI, 24.2 to 38.5 percent) fill in the rhBMP-2 group compared with 32.5 percent (95 percent CI, 22.1 to 42.9 percent) in the autologous population. Density analysis demonstrated identical average values between the groups (1.38 g/cc). These data demonstrate comparable bone regrowth and density values following secondary alveolar cleft repair using rhBMP-2/DBM scaffold versus autologous iliac bone graft. Cone beam computed tomography provides a more nuanced understanding of true bone regeneration within the alveolar cleft that may contribute to the information provided by occlusal radiographs alone. Therapeutic, II.

  16. Early changes in retinal structure and BMP2 expression in the retina and crystalline lens of streptozotocin-induced diabetic pigs.

    Science.gov (United States)

    Jeong, Jae Seung; Lee, Woon-Kyu; Moon, Yeon Sung; Kim, Na Rae

    2017-09-01

    This study aims to evaluate early changes in retinal structure and BMP2 expression in the retina and crystalline lens by comparing streptozotocin-induced diabetic pigs and normal control group pigs. Five eye samples from five diabetic Micro-pigs (Medikinetics, Pyeongtaek, Korea) and five eye samples from five control pigs bred in a specific pathogen-free area were used. Diabetes was developed through intravenous injection of nicotinamide and streptozotocin, and the average fasting glucose level was maintained at 250 mg/dL or higher for 16 weeks. To evaluate BMP2 expression in the retina and crystalline lens, Western blotting was performed. In Hematoxylin and Eosin staining, most diabetic pigs showed structural abnormalities in the inner plexiform layer. The number of nuclei in the ganglion cell layer within the range of 10 4 µm 2 was 3.78±0.60 for diabetic pigs and 5.57±1.07 for control group pigs, showing a statistically significant difference. In immunohistochemical staining, diabetic retinas showed an overall increase in BMP2 expression. In Western blotting, the average BMP2/actin level of diabetic retinas was 1.19±0.05, showing a significant increase compared to the 1.06±0.03 of the control group retinas ( P =0.016). The BMP2/actin level of diabetic crystalline lenses was similar to the control group crystalline lenses ( P =0.730). Compared to control group pigs, the number of nuclei in the inner nuclear layer of retinas from streptozotocin-induced diabetic pigs decreased, while an increase in BMP2 expression was observed in the retina of diabetic pigs.

  17. Effects of BMP-2 and dexamethasone on osteogenic differentiation of rat dental follicle progenitor cells seeded on three-dimensional beta-TCP

    Energy Technology Data Exchange (ETDEWEB)

    Xu Lulu; Jin Zuolin; Duan Yinzhong [Department of Orthodontics, Stomatological College, Fourth Military Medical University, Xi' an 710032 (China); Liu Hongchen; Wang Dongsheng; E Lingling [Department of Stomatology, China PLA General Hospital, Beijing 100853 (China); Xu Lin, E-mail: jinzuolin88@yahoo.com.c, E-mail: duanyinzhong@yahoo.com.c [Department of Stomatology, the First Hospital of PLA, Lanzhou 730000 (China)

    2009-12-15

    The aim of this study was to investigate the effects of BMP-2 and dexamethasone (Dex) on osteogenic differentiation of rat dental follicle progenitor cells (RDFCs) seeded on three-dimensional beta-TCP. The alkaline phosphatase (ALP), the calcium and phosphonium, the osteocalcin in media of the third passage RDFCs on biomaterial beta-TCP after 1-3, 3-7, 7-14 days of culture were examined respectively. The growth of cells on the scaffolds was observed by scanning electron microscope (SEM) after 3, 7 days of culture and by implanting in the backs of severe combined immunodeficient (SCID) mice for bone regeneration. The third passage RDFCs could be seen adhered, extended and proliferated on the beta-TCP by scanning electron microscopy. The ALP activity, the calcium and phosphoniums and the osteocalcin content of dexamethasone (10{sup -8} M) or/and BMP-2 (100 ng ml{sup -1}) were significantly higher than their existence in the control group. They were the significantly highest among four groups after joint application of BMP-2 and dexamethasone. After 8 weeks of implantation, the percentage of the new bones formed area in the RDFCs+beta-TCP+BMP-2+Dex group was significantly higher than that in the RDFCs+beta-TCP+BMP-2 group. In contrast, beta-TCP, RDFCs+beta-TCP+Dex and control constructs lacked new bone formation by histological staining and histomorphometric analysis. The BMP-2+Dex could significantly promote osteogenic differentiation of RDFCs on beta-TCP. beta-TCP supported fast cellular adhesion, proliferation and differentiation of RDFCs. The feasibility of its application in periodontal tissue engineering was also proved.

  18. Effects of BMP-2 and dexamethasone on osteogenic differentiation of rat dental follicle progenitor cells seeded on three-dimensional β-TCP

    International Nuclear Information System (INIS)

    Xu Lulu; Jin Zuolin; Duan Yinzhong; Liu Hongchen; Wang Dongsheng; E Lingling; Xu Lin

    2009-01-01

    The aim of this study was to investigate the effects of BMP-2 and dexamethasone (Dex) on osteogenic differentiation of rat dental follicle progenitor cells (RDFCs) seeded on three-dimensional β-TCP. The alkaline phosphatase (ALP), the calcium and phosphonium, the osteocalcin in media of the third passage RDFCs on biomaterial β-TCP after 1-3, 3-7, 7-14 days of culture were examined respectively. The growth of cells on the scaffolds was observed by scanning electron microscope (SEM) after 3, 7 days of culture and by implanting in the backs of severe combined immunodeficient (SCID) mice for bone regeneration. The third passage RDFCs could be seen adhered, extended and proliferated on the β-TCP by scanning electron microscopy. The ALP activity, the calcium and phosphoniums and the osteocalcin content of dexamethasone (10 -8 M) or/and BMP-2 (100 ng ml -1 ) were significantly higher than their existence in the control group. They were the significantly highest among four groups after joint application of BMP-2 and dexamethasone. After 8 weeks of implantation, the percentage of the new bones formed area in the RDFCs+β-TCP+BMP-2+Dex group was significantly higher than that in the RDFCs+β-TCP+BMP-2 group. In contrast, β-TCP, RDFCs+β-TCP+Dex and control constructs lacked new bone formation by histological staining and histomorphometric analysis. The BMP-2+Dex could significantly promote osteogenic differentiation of RDFCs on β-TCP. β-TCP supported fast cellular adhesion, proliferation and differentiation of RDFCs. The feasibility of its application in periodontal tissue engineering was also proved.

  19. Bone regeneration of critical calvarial defect in goat model by PLGA/TCP/rhBMP-2 scaffolds prepared by low-temperature rapid-prototyping technology.

    Science.gov (United States)

    Yu, D; Li, Q; Mu, X; Chang, T; Xiong, Z

    2008-10-01

    Active artificial bone composed of poly lactide-co-glycolide (PLGA)/ tricalcium phosphate (TCP) was prefabricated using low-temperature rapid-prototyping technology so that the process of osteogenesis could be observed in it. PLGA and TCP were the primary materials, they were molded at low temperature, then recombinant human bone morphogenetic protein-2 (rhBMP-2) was added to form an active artificial bone. Goats with standard cranial defects were randomly divided into experimental (implants with rhBMP-2 added) and control (implants without rhBMP-2) groups, and osteogenesis was observed and evaluated by imaging and biomechanical and histological examinations. The PLGA-TCP artificial bone scaffold (90% porosity) had large and small pores of approximately 360microm and 3-5microm diameter. Preliminary and complete repair of the cranial defect in the goats occurred 12 and 24 weeks after surgery, respectively. The three-point bending strength of the repaired defects attained that of the normal cranium. In conclusion, low-temperature rapid-prototyping technology can preserve the biological activity of this scaffold material. The scaffold has a good three-dimensional structure and it becomes an active artificial bone after loading with rhBMP-2 with a modest degradation rate and excellent osteogenesis in the goat.

  20. Vitamin C-linker-conjugated tripeptide AHK stimulates BMP-2-induced osteogenic differentiation of mouse myoblast C2C12 cells.

    Science.gov (United States)

    Jung, Jung-Il; Park, Kyeong-Yong; Lee, Yura; Park, Mira; Kim, Jiyeon

    2018-03-15

    Vitamin C-linker-conjugated Ala-His-Lys tripeptide (Vit C-AHK) is a derivative of Vitamin C-conjugated tripeptides, which were originally developed as a component of a product for collagen synthesis enhancement or human dermal fibroblast growth. Here, we investigated the effect of Vit C-AHK on bone morphogenetic protein (BMP)-2-induced osteoblast differentiation in a cell culture model. Vit C-AHK enhanced proliferation of C2C12 cells and induction of BMP-2-induced alkaline phosphatase, a typical marker of osteoblast differentiation. Vit C-AHK also stimulated the phosphorylation and translocation of Smad1/5/8 to the nucleus and phosphorylation of mitogen-activated protein kinases (MAPKs) including ERK1/2 and p38. In addition, Vit C-AHK enhanced the BMP-2-induced mRNA expression of osteoblast differentiation-related genes such as ALP, BMP-2, Osteocalcin, and Runx2. Our results suggest that Vit C-AHK exerts an enhancing effect on osteoblast proliferation and differentiation through activation of Smad1/5/8 and MAPK ERK1/2 and p38 signaling and without significant cytotoxicity. These results provide important data for the development of peptide-based bone-regenerative agents and treatment of bone-related disorders. Copyright © 2018 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  1. Dual Delivery of BMP-2 and bFGF from a New Nano-Composite Scaffold, Loaded with Vascular Stents for Large-Size Mandibular Defect Regeneration

    Directory of Open Access Journals (Sweden)

    Hang Zhao

    2013-06-01

    Full Text Available The aim of this study was to investigate the feasibility and advantages of the dual delivery of bone morphogenetic protein-2 (BMP-2 and basic fibroblast growth factor (bFGF from nano-composite scaffolds (PLGA/PCL/nHA loaded with vascular stents (PLCL/Col/nHA for large bone defect regeneration in rabbit mandibles. Thirty-six large bone defects were repaired in rabbits using engineering bone composed of allogeneic bone marrow mesenchymal stem cells (BMSCs, bFGF, BMP-2 and scaffolds composed of PLGA/PCL/nHA loaded with PLCL/Col/nHA. The experiments were divided into six groups: BMSCs/bFGF/BMP-2/scaffold, BMSCs/BMP-2/scaffold, BMSCs/bFGF/scaffold, BMSCs/scaffold, scaffold alone and no treatment. Sodium alginate hydrogel was used as the carrier for BMP-2 and bFGF and its features, including gelling, degradation and controlled release properties, was detected by the determination of gelation and degradation time coupled with a controlled release study of bovine serum albumin (BSA. AlamarBlue assay and alkaline phosphatase (ALP activity were used to evaluate the proliferation and osteogenic differentiation of BMSCs in different groups. X-ray and histological examinations of the samples were performed after 4 and 12 weeks post-implantation to clarify new bone formation in the mandible defects. The results verified that the use of sodium alginate hydrogel as a controlled release carrier has good sustained release ability, and the combined application of bFGF and BMP-2 could significantly promote the proliferation and osteogenic differentiation of BMSCs (p < 0.05 or p < 0.01. In addition, X-ray and histological examinations of the samples exhibited that the dual release group had significantly higher bone formation than the other groups. The above results indicate that the delivery of both growth factors could enhance new bone formation and vascularization compared with delivery of BMP-2 or bFGF alone, and may supply a promising way of repairing large

  2. Efficacy of rhBMP-2 Loaded PCL/β-TCP/bdECM Scaffold Fabricated by 3D Printing Technology on Bone Regeneration

    Directory of Open Access Journals (Sweden)

    Eun-Bin Bae

    2018-01-01

    Full Text Available This study was undertaken to evaluate the effect of 3D printed polycaprolactone (PCL/β-tricalcium phosphate (β-TCP scaffold containing bone demineralized and decellularized extracellular matrix (bdECM and human recombinant bone morphogenetic protein-2 (rhBMP-2 on bone regeneration. Scaffolds were divided into PCL/β-TCP, PCL/β-TCP/bdECM, and PCL/β-TCP/bdECM/BMP groups. In vitro release kinetics of rhBMP-2 were determined with respect to cell proliferation and osteogenic differentiation. These three reconstructive materials were implanted into 8 mm diameter calvarial bone defect in male Sprague-Dawley rats. Animals were sacrificed four weeks after implantation for micro-CT, histologic, and histomorphometric analyses. The findings obtained were used to calculate new bone volumes (mm3 and new bone areas (%. Excellent cell bioactivity was observed in the PCL/β-TCP/bdECM and PCL/β-TCP/bdECM/BMP groups, and new bone volume and area were significantly higher in the PCL/β-TCP/bdECM/BMP group than in the other groups (p<.05. Within the limitations of this study, bdECM printed PCL/β-TCP scaffolds can reproduce microenvironment for cells and promote adhering and proliferating the cells onto scaffolds. Furthermore, in the rat calvarial defect model, the scaffold which printed rhBMP-2 loaded bdECM stably carries rhBMP-2 and enhances bone regeneration confirming the possibility of bdECM as rhBMP-2 carrier.

  3. Cryogenic 3D printing for producing hierarchical porous and rhBMP-2-loaded Ca-P/PLLA nanocomposite scaffolds for bone tissue engineering.

    Science.gov (United States)

    Wang, Chong; Zhao, Qilong; Wang, Min

    2017-06-07

    The performance of bone tissue engineering scaffolds can be assessed through cell responses to scaffolds, including cell attachment, infiltration, morphogenesis, proliferation, differentiation, etc, which are determined or heavily influenced by the composition, structure, mechanical properties, and biological properties (e.g. osteoconductivity and osteoinductivity) of scaffolds. Although some promising 3D printing techniques such as fused deposition modeling and selective laser sintering could be employed to produce biodegradable bone tissue engineering scaffolds with customized shapes and tailored interconnected pores, effective methods for fabricating scaffolds with well-designed hierarchical porous structure (both interconnected macropores and surface micropores) and tunable osteoconductivity/osteoinductivity still need to be developed. In this investigation, a novel cryogenic 3D printing technique was investigated and developed for producing hierarchical porous and recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded calcium phosphate (Ca-P) nanoparticle/poly(L-lactic acid) nanocomposite scaffolds, in which the Ca-P nanoparticle-incorporated scaffold layer and rhBMP-2-encapsulated scaffold layer were deposited alternatingly using different types of emulsions as printing inks. The mechanical properties of the as-printed scaffolds were comparable to those of human cancellous bone. Sustained releases of Ca 2+ ions and rhBMP-2 were achieved and the biological activity of rhBMP-2 was well-preserved. Scaffolds with a desirable hierarchical porous structure and dual delivery of Ca 2+ ions and rhBMP-2 exhibited superior performance in directing the behaviors of human bone marrow-derived mesenchymal stem cells and caused improved cell viability, attachment, proliferation, and osteogenic differentiation, which has suggested their great potential for bone tissue engineering.

  4. Effect of Emdogain enamel matrix derivative and BMP-2 on the gene expression and mineralized nodule formation of alveolar bone proper-derived stem/progenitor cells.

    Science.gov (United States)

    Fawzy El-Sayed, Karim M; Dörfer, Christof; Ungefroren, Hendrick; Kassem, Neemat; Wiltfang, Jörg; Paris, Sebastian

    2014-07-01

    The objective of this study was to evaluate the effect of Emdogain (Enamel Matrix Derivative, EMD) and Bone Morphogenetic Protein-2 (BMP-2), either solely or in combination, on the gene expression and mineralized nodule formation of alveolar bone proper-derived stem/progenitor cells. Stem/progenitor cells were isolated from human alveolar bone proper, magnetically sorted using STRO-1 antibodies, characterized flowcytometrically for their surface markers' expression, and examined for colony formation and multilineage differentiation potential. Subsequently, cells were treated over three weeks with 100 μg/ml Emdogain (EMD-Group), or 100 ng/ml BMP-2 (BMP-Group), or a combination of 100 ng/ml BMP-2 and 100 μg/ml Emdogain (BMP/EMD-Group). Unstimulated stem/progenitor cells (MACS(+)-Group) and osteoblasts (OB-Group) served as controls. Osteogenic gene expression was analyzed using RTq-PCR after 1, 2 and 3 weeks (N = 3/group). Mineralized nodule formation was evaluated by Alizarin-Red staining. BMP and EMD up-regulated the osteogenic gene expression. The BMP Group showed significantly higher expression of Collagen-I, III, and V, Alkaline phosphatase and Osteonectin compared to MACS(+)- and OB-Group (p < 0.05; Two-way ANOVA/Bonferroni) with no mineralized nodule formation. Under in-vitro conditions, Emdogain and BMP-2 up-regulate the osteogenic gene expression of stem/progenitor cells. The combination of BMP-2 and Emdogain showed no additive effect and would not be recommended for a combined clinical stimulation. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  5. Ectopic expression of Msx-2 in posterior limb bud mesoderm impairs limb morphogenesis while inducing BMP-4 expression, inhibiting cell proliferation, and promoting apoptosis.

    Science.gov (United States)

    Ferrari, D; Lichtler, A C; Pan, Z Z; Dealy, C N; Upholt, W B; Kosher, R A

    1998-05-01

    expression of BMP-4, a secreted signaling molecule that is coexpressed with Msx-2 during normal limb development in the anterior limb mesoderm, the posterior necrotic zone, and interdigital mesenchyme. This indicates that Msx-2 regulates BMP-4 expression and that the suppressive effects of Msx-2 on limb morphogenesis might be mediated in part by BMP-4. These studies indicate that during normal limb development Msx-2 is a key component of a regulatory network that delimits the boundaries of the progress zone by suppressing the morphogenesis of the regions of the limb mesoderm in which it is highly expressed, thus restricting the outgrowth and formation of skeletal elements and associated structures to the progress zone. We also report that rather large numbers of apoptotic cells as well as proliferating cells are present throughout the AER during all stages of normal limb development we have examined, indicating that many of the cells of the AER are continuously undergoing programmed cell death at the same time that new AER cells are being generated by cell proliferation. Thus, a balance between cell proliferation and programmed cell death may play a very important role in maintaining the activity of the AER. Copyright 1998 Academic Press.

  6. Smad4 mediated BMP2 signal is essential for the regulation of GATA4 and Nkx2.5 by affecting the histone H3 acetylation in H9c2 cells

    International Nuclear Information System (INIS)

    Si, Lina; Shi, Jin; Gao, Wenqun; Zheng, Min; Liu, Lingjuan; Zhu, Jing; Tian, Jie

    2014-01-01

    Highlights: • BMP2 can upregulated cardiac related gene GATA4, Nkx2.5, MEF2c and Tbx5. • Inhibition of Smad4 decreased BMP2-induced hyperacetylation of histone H3. • Inhibition of Smad4 diminished BMP2-induced overexpression of GATA4 and Nkx2.5. • Inhibition of Smad4 decreased hyperacetylated H3 in the promoter of GATA4 and Nkx2.5. • Smad4 is essential for BMP2 induced hyperacetylated histone H3. - Abstract: BMP2 signaling pathway plays critical roles during heart development, Smad4 encodes the only common Smad protein in mammals, which is a pivotal nuclear mediator. Our previous studies showed that BMP2 enhanced the expression of cardiac transcription factors in part by increasing histone H3 acetylation. In the present study, we tested the hypothesis that Smad4 mediated BMP2 signaling pathway is essential for the expression of cardiac core transcription factors by affecting the histone H3 acetylation. We successfully constructed a lentivirus-mediated short hairpin RNA interference vector targeting Smad4 (Lv-Smad4) in rat H9c2 embryonic cardiac myocytes (H9c2 cells) and demonstrated that it suppressed the expression of the Smad4 gene. Cultured H9c2 cells were transfected with recombinant adenoviruses expressing human BMP2 (AdBMP2) with or without Lv-Smad4. Quantitative real-time RT-PCR analysis showed that knocking down of Smad4 substantially inhibited both AdBMP2-induced and basal expression levels of cardiac transcription factors GATA4 and Nkx2.5, but not MEF2c and Tbx5. Similarly, chromatin immunoprecipitation (ChIP) analysis showed that knocking down of Smad4 inhibited both AdBMP2-induced and basal histone H3 acetylation levels in the promoter regions of GATA4 and Nkx2.5, but not of Tbx5 and MEF2c. In addition, Lv-Smad4 selectively suppressed AdBMP2-induced expression of HAT p300, but not of HAT GCN5 in H9c2 cells. The data indicated that inhibition of Smad4 diminished both AdBMP2 induced and basal histone acetylation levels in the promoter regions of

  7. Smad4 mediated BMP2 signal is essential for the regulation of GATA4 and Nkx2.5 by affecting the histone H3 acetylation in H9c2 cells

    Energy Technology Data Exchange (ETDEWEB)

    Si, Lina; Shi, Jin; Gao, Wenqun [Heart Centre, Children’s Hospital of Chongqing Medical University, 136 Zhongshan 2nd Road, Yu Zhong District, Chongqing 400014 (China); Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, 136 Zhongshan 2nd Road, Yu Zhong District, Chongqing 400014 (China); Zheng, Min [Heart Centre, Children’s Hospital of Chongqing Medical University, 136 Zhongshan 2nd Road, Yu Zhong District, Chongqing 400014 (China); Liu, Lingjuan; Zhu, Jing [Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, 136 Zhongshan 2nd Road, Yu Zhong District, Chongqing 400014 (China); Tian, Jie, E-mail: jietian@cqmu.edu.cn [Heart Centre, Children’s Hospital of Chongqing Medical University, 136 Zhongshan 2nd Road, Yu Zhong District, Chongqing 400014 (China)

    2014-07-18

    Highlights: • BMP2 can upregulated cardiac related gene GATA4, Nkx2.5, MEF2c and Tbx5. • Inhibition of Smad4 decreased BMP2-induced hyperacetylation of histone H3. • Inhibition of Smad4 diminished BMP2-induced overexpression of GATA4 and Nkx2.5. • Inhibition of Smad4 decreased hyperacetylated H3 in the promoter of GATA4 and Nkx2.5. • Smad4 is essential for BMP2 induced hyperacetylated histone H3. - Abstract: BMP2 signaling pathway plays critical roles during heart development, Smad4 encodes the only common Smad protein in mammals, which is a pivotal nuclear mediator. Our previous studies showed that BMP2 enhanced the expression of cardiac transcription factors in part by increasing histone H3 acetylation. In the present study, we tested the hypothesis that Smad4 mediated BMP2 signaling pathway is essential for the expression of cardiac core transcription factors by affecting the histone H3 acetylation. We successfully constructed a lentivirus-mediated short hairpin RNA interference vector targeting Smad4 (Lv-Smad4) in rat H9c2 embryonic cardiac myocytes (H9c2 cells) and demonstrated that it suppressed the expression of the Smad4 gene. Cultured H9c2 cells were transfected with recombinant adenoviruses expressing human BMP2 (AdBMP2) with or without Lv-Smad4. Quantitative real-time RT-PCR analysis showed that knocking down of Smad4 substantially inhibited both AdBMP2-induced and basal expression levels of cardiac transcription factors GATA4 and Nkx2.5, but not MEF2c and Tbx5. Similarly, chromatin immunoprecipitation (ChIP) analysis showed that knocking down of Smad4 inhibited both AdBMP2-induced and basal histone H3 acetylation levels in the promoter regions of GATA4 and Nkx2.5, but not of Tbx5 and MEF2c. In addition, Lv-Smad4 selectively suppressed AdBMP2-induced expression of HAT p300, but not of HAT GCN5 in H9c2 cells. The data indicated that inhibition of Smad4 diminished both AdBMP2 induced and basal histone acetylation levels in the promoter regions of

  8. Retinal and choroidal expression of BMP-2 in lens-induced myopia and recovery from myopia in guinea pigs.

    Science.gov (United States)

    Li, Honghui; Wu, Juan; Cui, Dongmei; Zeng, Junwen

    2016-03-01

    The present study investigated the retinal and choroidal expression of bone morphogenetic protein-2 (BMP-2) in myopia and in myopia recovery in a guinea pig model. For this investigation, two groups of guinea pigs, lens‑induced myopia and recovery from myopia, were used, and defocused myopia was induced the guinea pigs wearing ‑4.00 D lenses on the right eyes for 3 weeks, with the left eyes serving as the contralateral. In the following week, the lenses of the guinea pigs in the recovery group were removed, and the refractive power and axial length were measured. The expression of BMP‑2 in the eyeballs was observed using immunohistochemistry and analyzed using Western blot analysis. After 3 weeks, the eyes acquired relative myopia and longer axial lengths in the two groups of guinea pigs. After 1 week without lenses in the recovery group, the myopia and axial lengths regressed. Immunofluorescence staining showed that BMP‑2 was expressed in the posterior retina, RPE, choroid and sclera. The expression of BMP‑2 decreased in the myopic retina of the guinea pigs. Following the regression of myopia in the recovery group, no difference in the expression of BMP‑2 was observed between the recovered treated eyes and the contralateral eyes. The choroidal expression level of BMP‑2 in the treated eyes showed no significant changes in either group. Therefore, BMP‑2 may be involved in the development of myopia, however, it does not have a primary role in the retinal and choroidal signals regulating scleral remodeling.

  9. Osteogenesis differentiation of human periodontal ligament cells by CO2 laser-treatment stimulating macrophages via BMP2 signalling pathway

    International Nuclear Information System (INIS)

    Hsieh, Wen-Hui; Chen, Yi-Jyun; Hung, Chi-Jr; Huang, Tsui-Hsien; Kao, Chia-Tze; Shie, Ming-You

    2014-01-01

    Immune reactions play an important role in determining the biostimulation of bone formation, either in new bone formation or inflammatory fibrous tissue encapsulation. Macrophage cell, the important effector cells in the immune reaction, which are indispensable for osteogenesis and their heterogeneity and plasticity, render macrophages a primer target for immune system modulation. However, there are very few studies about the effects of macrophage cells on laser treatment-regulated osteogenesis. In this study, we used CO 2 laser as a model biostimulation to investigate the role of macrophage cells on the CO 2 laser stimulated osteogenesis. Bone morphogenetic protein 2 (BMP2) was also significantly up regulated by the CO 2 laser stimulation, indicating that macrophage may participate in the CO 2 laser stimulated osteogenesis. Interestingly, when laser treatment macrophage-conditioned medium were applied to human periodontal ligament cells (hPDLs), the osteogenesis differentiation of hPDLs was significantly enhanced, indicating the important role of macrophages in CO 2 laser-induced osteogenesis. These findings provided valuable insights into the mechanism of CO 2 laser-stimulated osteogenic differentiation, and a strategy to optimize the evaluation system for the in vitro osteogenesis capacity of laser treatment. (paper)

  10. TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants and arrests downstream differentiation at an early stage of hypertrophy.

    Science.gov (United States)

    Shintani, Nahoko; Siebenrock, Klaus A; Hunziker, Ernst B

    2013-01-01

    Synovial explants furnish an in-situ population of mesenchymal stem cells for the repair of articular cartilage. Although bone morphogenetic protein 2 (BMP-2) induces the chondrogenesis of bovine synovial explants, the cartilage formed is neither homogeneously distributed nor of an exclusively hyaline type. Furthermore, the downstream differentiation of chondrocytes proceeds to the stage of terminal hypertrophy, which is inextricably coupled with undesired matrix mineralization. With a view to optimizing BMP-2-induced chondrogenesis, the modulating influences of fibroblast growth factor 2 (FGF-2) and transforming growth factor beta 1 (TGF-ß1) were investigated. Explants of bovine calf metacarpal synovium were exposed to BMP-2 (200 ng/ml) for 4 (or 6) weeks. FGF-2 (10 ng/ml) or TGF-ß1 (10 ng/ml) was introduced at the onset of incubation and was present either during the first week of culturing alone or throughout its entire course. FGF-2 enhanced the BMP-2-induced increase in metachromatic staining for glycosaminoglycans (GAGs) only when it was present during the first week of culturing alone. TGF-ß1 enhanced not only the BMP-2-induced increase in metachromasia (to a greater degree than FGF-2), but also the biochemically-assayed accumulation of GAGs, when it was present throughout the entire culturing period; in addition, it arrested the downstream differentiation of cells at an early stage of hypertrophy. These findings were corroborated by an analysis of the gene- and protein-expression levels of key cartilaginous markers and by an estimation of individual cell volume. TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants, improves the hyaline-like properties of the neocartilage, and arrests the downstream differentiation of cells at an early stage of hypertrophy. With the prospect of engineering a mature, truly articular type of cartilage in the context of clinical repair, our findings will be of importance in fine-tuning the

  11. Evaluation of a Novel HA/ZrO2-Based Porous Bioceramic Artificial Vertebral Body Combined with a rhBMP-2/Chitosan Slow-Release Hydrogel.

    Directory of Open Access Journals (Sweden)

    Yihui Shi

    Full Text Available A new HA/ZrO2-based porous bioceramic artificial vertebral body (AVB, carried a recombinant human bone morphogenetic protein-2 (rhBMP-2/chitosan slow-release hydrogel was prepared to repair vertebral bone defect in beagles. An ionic cross-linking was used to prepare the chitosan hydrogel (CS gel as the rhBMP-2 slow-release carrier. The vertebral body defects were implanted with the rhBMP-2-loaded AVB in group A, or a non-drug-loaded AVB in group B, or autologous iliac in group C. The encapsulation rate of rhBMP-2 in rhBMP-2-loaded CS gel was 91.88±1.53%, with a drug load of 39.84±2.34 ng/mg. At 6, 12, 24 weeks postoperatively, radiography showed that the bone calluses gradually increased with time in group A, where the artificial vertebral body had completely fused with host-bone at 24 weeks after surgery. In group C, an apparent bone remodeling was occurred in the early stages, and the graft-bone and host-bone had also fused completely at 24 weeks postoperatively. In group B, fusion occurred less than in groups A and C. At 24 weeks after surgery, micro-computed tomography (Micro-CT revealed that the volume of newly-formed bone in group A was significantly more than in group B (p<0.05. At 24 weeks after surgery, ultra-compressive strengths of the operated segments were 14.03±1.66 MPa in group A, 8.62±1.24 MPa in group B, and 13.78±1.43 MPa in group C. Groups A and C were both significantly higher than group B (p < 0.05. At 24 weeks postoperatively, the hard tissue sections showed that the AVB of group A had tightly fused with host bone, and that pores of the AVB had been filled with abundant nearly mature bone, and that the new bone structured similarly to a trabecular framework, which was similar to that in group C. In contrast, implant fusion of the AVB in group B was not as apparent as group A. In conclusion, the novel HA/ZrO2-based porous bioceramic AVB carried the rhBMP-2-loaded CS gel can promote the repair of bony defect, and induce

  12. TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants and arrests downstream differentiation at an early stage of hypertrophy.

    Directory of Open Access Journals (Sweden)

    Nahoko Shintani

    Full Text Available Synovial explants furnish an in-situ population of mesenchymal stem cells for the repair of articular cartilage. Although bone morphogenetic protein 2 (BMP-2 induces the chondrogenesis of bovine synovial explants, the cartilage formed is neither homogeneously distributed nor of an exclusively hyaline type. Furthermore, the downstream differentiation of chondrocytes proceeds to the stage of terminal hypertrophy, which is inextricably coupled with undesired matrix mineralization. With a view to optimizing BMP-2-induced chondrogenesis, the modulating influences of fibroblast growth factor 2 (FGF-2 and transforming growth factor beta 1 (TGF-ß1 were investigated.Explants of bovine calf metacarpal synovium were exposed to BMP-2 (200 ng/ml for 4 (or 6 weeks. FGF-2 (10 ng/ml or TGF-ß1 (10 ng/ml was introduced at the onset of incubation and was present either during the first week of culturing alone or throughout its entire course. FGF-2 enhanced the BMP-2-induced increase in metachromatic staining for glycosaminoglycans (GAGs only when it was present during the first week of culturing alone. TGF-ß1 enhanced not only the BMP-2-induced increase in metachromasia (to a greater degree than FGF-2, but also the biochemically-assayed accumulation of GAGs, when it was present throughout the entire culturing period; in addition, it arrested the downstream differentiation of cells at an early stage of hypertrophy. These findings were corroborated by an analysis of the gene- and protein-expression levels of key cartilaginous markers and by an estimation of individual cell volume.TGF-ß1 enhances the BMP-2-induced chondrogenesis of bovine synovial explants, improves the hyaline-like properties of the neocartilage, and arrests the downstream differentiation of cells at an early stage of hypertrophy. With the prospect of engineering a mature, truly articular type of cartilage in the context of clinical repair, our findings will be of importance in fine-tuning the

  13. Efficacy of rhBMP-2 loaded PCL/PLGA/β-TCP guided bone regeneration membrane fabricated by 3D printing technology for reconstruction of calvaria defects in rabbit

    International Nuclear Information System (INIS)

    Shim, Jin-Hyung; Jeong, Chang-Mo; Huh, Jung-Bo; Jang, Jinah; Jeong, Sung-In; Cho, Dong-Woo; Yoon, Min-Chul

    2014-01-01

    We successfully fabricated a three-dimensional (3D) printing-based PCL/PLGA/β-TCP guided bone regeneration (GBR) membrane that slowly released rhBMP-2. To impregnate the GBR membrane with intact rhBMP-2, collagen solution encapsulating rhBMP-2 (5 µg ml −1 ) was infused into pores of a PCL/PLGA/β-TCP membrane constructed using a 3D printing system with four dispensing heads. In a release profile test, sustained release of rhBMP-2 was observed for up to 28 d. To investigate the efficacy of the GBR membrane on bone regeneration, PCL/PLGA/β-TCP membranes with or without rhBMP-2 were implanted in an 8 mm calvaria defect of rabbits. Bone formation was evaluated at weeks 4 and 8 histologically and histomorphometrically. A space making ability of the GBR membrane was successfully maintained in both groups, and significantly more new bone was formed at post-implantation weeks 4 and 8 by rhBMP-2 loaded GBR membranes. Interestingly, implantation with rhBMP-2 loaded GBR membranes led to almost entire healing of calvaria defects within 8 weeks. (paper)

  14. TGF-β1, GDF-5, and BMP-2 stimulation induces chondrogenesis in expanded human articular chondrocytes and marrow-derived stromal cells.

    Science.gov (United States)

    Murphy, Meghan K; Huey, Daniel J; Hu, Jerry C; Athanasiou, Kyriacos A

    2015-03-01

    Replacement of degenerated cartilage with cell-based cartilage products may offer a long-term solution to halt arthritis' degenerative progression. Chondrocytes are frequently used in cell-based FDA-approved cartilage products; yet human marrow-derived stromal cells (hMSCs) show significant translational potential, reducing donor site morbidity and maintaining their undifferentiated phenotype with expansion. This study sought to investigate the effects of transforming growth factor β1 (TGF-β1), growth/differentiation factor 5 (GDF-5), and bone morphogenetic protein 2 (BMP-2) during postexpansion chondrogenesis in human articular chondrocytes (hACs) and to compare chondrogenesis in passaged hACs with that of passaged hMSCs. Through serial expansion, chondrocytes dedifferentiated, decreasing expression of chondrogenic genes while increasing expression of fibroblastic genes. However, following expansion, 10 ng/mL TGF-β1, 100 ng/mL GDF-5, or 100 ng/mL BMP-2 supplementation during three-dimensional aggregate culture each upregulated one or more markers of chondrogenic gene expression in both hACs and hMSCs. Additionally, in both cell types, the combination of TGF-β1, GDF-5, and BMP-2 induced the greatest upregulation of chondrogenic genes, that is, Col2A1, Col2A1/Col1A1 ratio, SOX9, and ACAN, and synthesis of cartilage-specific matrix, that is, glycosaminoglycans (GAGs) and ratio of collagen II/I. Finally, TGF-β1, GDF-5, and BMP-2 stimulation yielded mechanically robust cartilage rich in collagen II and GAGs in both cell types, following 4 weeks maturation. This study illustrates notable success in using the self-assembling method to generate robust, scaffold-free neocartilage constructs using expanded hACs and hMSCs. © 2014 AlphaMed Press.

  15. Expression of the bone morphogenetic protein-2 (BMP2 in the human cumulus cells as a biomarker of oocytes and embryo quality

    Directory of Open Access Journals (Sweden)

    Sirin B Demiray

    2017-01-01

    Full Text Available Background: The members of the transforming growth factor-B superfamily, as the bone morphogenetic proteins (BMPs subfamily and anti-Müllerian hormone (AMH, play a role during follicular development, and the bone morphogenetic protein-2 (BMP2, AMH, and THY1 are expressed in ovaries. Aim: This study was designed to define whether or not the expressions of these proteins in human cumulus cells (CCs can be used as predictors of the oocyte and embryo competence. Settings and Design: The study included nine female patients who were diagnosed as idiopathic infertility, aged 25–33 years (median 30 years and underwent Assisted Reproductive Technologies. Materials and Methods: The CCs from 60 oocyte–cumulus complexes obtained from the nine patients were evaluated with immunofluorescence staining in respect of BMPs, AMH and THY1 markers. The CCs surrounding the same oocytes were evaluated separately according to the oocyte and embryo quality. Statistical Analysis: Quantitative data were statistically analyzed for differences using the two-sided Mann–Whitney U test (P < 0.05. Results and Conclusions: Significant differences in immunofluorescence staining were observed in oocyte quality and embryo quality for the BMP2 only (P < 0.05. No significant differences were observed for AMH or CD90/THY1. Conclusion: These results demonstrated that there is a significant difference in the expression of BMP2 in the CCs of good quality oocytes and subsequently a good embryo.

  16. Delta-like 1/fetal antigen 1(DLK1/FA1) inhibits BMP2 induced osteoblast differentiation through modulation of NFκB signaling pathway

    DEFF Research Database (Denmark)

    Qiu, Weimin; Abdallah, Basem; Kassem, Moustapha

    DLK1/FA1 (delta-like 1/fetal antigen-1) is a negative regulator of bone mass that acts to inhibit osteoblast differentiation and stimulate osteoclast differentiation. However, the molecular mechanisms underlying these effects are not known. Thus, we studied the effect of DLK1/FA1 on different...... osteogenic factors-induced osteoblast differentiation. We identified DLK1/FA1 as an inhibitor of BMP2-induced osteogenesis in mouse myoblast C2C12 cells. Stable overexpression of DLK1/FA1 in C2C12 cells or the addition of its soluble form protein FA1 significantly inhibited BMP2-induced osteogenesis...... as assessed by reduced Alp activity and osteogenic gene expression including Alp, Col1a1, Runx2 and Bglap. In addition, DLK1/FA1 inhibited BMP signaling as demonstrated by reduced gene expression of BMP-responsive genes: Junb and Id1, reduced BMP2 induced luciferase activity in C2C12 BMP luciferase reporter...

  17. Effects of piezosurgery in accelerating the movement of orthodontic alveolar bone tooth of rats and the expression mechanism of BMP-2.

    Science.gov (United States)

    Han, Jinyou; He, Hong

    2016-11-01

    The aim of the study was to investigate the effects of piezosurgery in accelerating the movement of orthodontic alveolar bone tooth of rats and the expression mechanism of bone morphogenetic protein-2 (BMP-2). Adult male Wistar rats (n=30), with an age range of 14-15 weeks, and an average weight of 250±16 g were used. The animals were randomly divided into the control and observation groups. The rats in the control group were injected with 25-dihydroxyvitamin (1,25-dihydroxycholecalciferol) into their dental ligament. The rats in the observation group were placed with an orthodontic device between the first molar and central incisor in the maxillary. On the first day after animal treatment, piezosurgery stimulation was performed on the first molar in maxillary. The changes of the movement distance of the first molar and gum surface temperature on days 1, 3, 5, 7 and 14 were then compared. Immunohistochemical staining was performed to detect the expression of BMP-2 of periodontal tissue in the tension side of the first molar. Tooth movement distance in the observation group on days 5, 7 and 14 was significantly longer than that in the control group (ppiezosurgery may significantly accelerate the movement of orthodontic alveolar bone tooth of rats and be associated with an increasing BMP-2 expression.

  18. The effect of a slow mode of BMP-2 delivery on the inflammatory response provoked by bone-defect-filling polymeric scaffolds.

    Science.gov (United States)

    Wu, Gang; Liu, Yuelian; Iizuka, Tateyuki; Hunziker, Ernst Bruno

    2010-10-01

    We investigated the inflammatory response to, and the osteoinductive efficacies of, four polymers (collagen, Ethisorb, PLGA and Polyactive) that bore either an adsorbed (fast-release kinetics) or a calcium-phosphate-coating-incorporated (slow-release kinetics) depot of BMP-2. Titanium-plate-supported discs of each polymer (n = 6 per group) were implanted at an ectopic (subcutaneous) ossification site in rats (n = 48). Five weeks later, they were retrieved for a histomorphometric analysis of the volumes of ectopic bone and foreign-body giant cells (a gauge of inflammatory reactivity), and the degree of polymer degradation. For each polymer, the osteoinductive efficacy of BMP-2 was higher when it was incorporated into a coating than when it was directly adsorbed onto the material. This mode of BMP-2 carriage was consistently associated with an attenuation of the inflammatory response. For coated materials, the volume density of foreign-body giant cells was inversely correlated with the volume density of bone (r(2) = 0.96), and the volume density of bone was directly proportional to the surface-area density of the polymer (r(2) = 0.97). Following coating degradation, other competitive factors, such as the biocompatibility and the biodegradability of the polymer itself, came into play. 2010 Elsevier Ltd. All rights reserved.

  19. Conditions Inducing Excessive O-GlcNAcylation Inhibit BMP2-Induced Osteogenic Differentiation of C2C12 Cells.

    Science.gov (United States)

    Gu, Hanna; Song, Mina; Boonanantanasarn, Kanitsak; Baek, Kyunghwa; Woo, Kyung Mi; Ryoo, Hyun-Mo; Baek, Jeong-Hwa

    2018-01-09

    Hyperglycemic conditions in diabetic patients can affect various cellular functions, including the modulation of osteogenic differentiation. However, the molecular mechanisms by which hyperglycemia affects osteogenic differentiation are yet to be clarified. This study aimed to investigate whether the aberrant increase in protein O -linked-β- N -acetylglucosamine glycosylation ( O -GlcNAcylation) contributes to the suppression of osteogenic differentiation due to hyperglycemia. To induce osteogenic differentiation, C2C12 cells were cultured in the presence of recombinant human bone morphogenetic protein 2 (BMP2). Excessive protein O -GlcNAcylation was induced by treating C2C12 cells with high glucose, glucosamine, or N -acetylglucosamine concentrations or by O -GlcNAc transferase (OGT) overexpression. The effect of O -GlcNAcylation on osteoblast differentiation was then confirmed by examining the expression levels of osteogenic marker gene mRNAs, activity of alkaline phosphatase, and transcriptional activity of Runx2, a critical transcription factor for osteoblast differentiation and bone formation. Cell treatment with high glucose, glucosamine or N -acetylglucosamine increased O -GlcNAcylation of Runx2 and the total levels of O -GlcNAcylated proteins, which led to a decrease in the transcriptional activity of Runx2, expression levels of osteogenic marker genes (Runx2, osterix, alkaline phosphatase, and type I collagen), and activity of alkaline phosphatase. These inhibitory effects were rescued by lowering protein O -GlcNAcylation levels by adding STO45849, an OGT inhibitor, or by overexpressing β- N -acetylglucosaminidase. Our findings suggest that excessive protein O -GlcNAcylation contributes to high glucose-suppressed osteogenic differentiation.

  20. The effect of core decompression on local expression of BMP-2, PPAR-γ and bone regeneration in the steroid-induced femoral head osteonecrosis

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    Wang Wei

    2012-08-01

    Full Text Available Abstract Background To investigate the efficacy of the sole core decompression surgery for the treatment of steroid-induced femoral head osteonecrosis. Methods The model was established by administration of steroids in combination with horse serum. The rabbits with bilateral femoral head osteonecrosis were randomly selected to do the one side of core decompression. The other side was used as the sham. Quantitative RT-PCR and western blot techniques were used to measure the local expression of BMP-2 and PPAR-γ. Bone tissues from control and operation groups were histologically analyzed by H&E staining. The comparisons of the local expression of BMP-2 and PPAR-γ and the bone regeneration were further analyzed between different groups at each time point. Results The expression of BMP-2 in the osteonecrosis femoral head with or without decompression was significantly lower than that in normal animals. BMP-2 expression both showed the decreasing trend with the increased post-operation time. No significant difference of BMP-2 expression occurred between femoral head osteonecrosis with and without decompression. The PPAR-γ expression in the femoral head osteonecrosis with and without core decompression both was significantly higher than that in control. Its expression pattern showed a significantly increased trend with increased the post-operation time. However, there was no significant difference of PPAR-γ expression between the femoral head osteonecrosis with and without decompression at each time point. Histopathological analysis revealed that new trabecular bone and a large number of osteoblasts were observed in the steroid-induced femoral head osteonecrosis with lateral decompression at 8 weeks after surgery, but there still existed trabecular bone fractures and bone necrosis. Conclusions Although decompression takes partial effect in promoting bone regeneration in the early treatment of femoral head osteonecrosis, such an effect does not

  1. Quinoline compound KM11073 enhances BMP-2-dependent osteogenic differentiation of C2C12 cells via activation of p38 signaling and exhibits in vivo bone forming activity.

    Directory of Open Access Journals (Sweden)

    Seung-hwa Baek

    Full Text Available Recombinant human bone morphogenetic protein (rhBMP-2 has been approved by the FDA for clinical application, but its use is limited due to high cost and a supra-physiological dose for therapeutic efficacy. Therefore, recent studies have focused on the generation of new therapeutic small molecules to induce bone formation or potentiate the osteogenic activity of BMP-2. Here, we show that [4-(7-chloroquinolin-4-yl piperazino][1-phenyl-5-(trifluoromethyl-1H-pyrazol-4-yl]methanone (KM11073 strongly enhances the BMP-2-stimulated induction of alkaline phosphatase (ALP, an early phase biomarker of osteoblast differentiation, in bi-potential mesenchymal progenitor C2C12 cells. The KM11073-mediated ALP induction was inhibited by the BMP antagonist noggin, suggesting that its osteogenic activity occurs via BMP signaling. In addition, a pharmacological inhibition study suggested the involvement of p38 activation in the osteogenic action of KM11073 accompanied by enhanced expression of BMP-2, -6, and -7 mRNA. Furthermore, the in vivo osteogenic activity of KM11073 was confirmed in zebrafish and mouse calvarial bone formation models, suggesting the possibility of its single use for bone formation. In conclusion, the combination of rhBMP-2 with osteogenic small molecules could reduce the use of expensive rhBMP-2, mitigating the undesirable side effects of its supra-physiological dose for therapeutic efficacy. Moreover, due to their inherent physical properties, small molecules could represent the next generation of regenerative medicine.

  2. Acellular dermal matrix loading with bFGF achieves similar acceleration of bone regeneration to BMP-2 via differential effects on recruitment, proliferation and sustained osteodifferentiation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Du, Mi; Zhu, Ting; Duan, Xiaoqi; Ge, Shaohua; Li, Ning; Sun, Qinfeng; Yang, Pishan

    2017-01-01

    New generation of barrier membranes has been developed, which not only act as barriers but also as delivery devices to release specific growth factors. This study observed biological behaviors of bone morrow mesenchymal stem cells (BMMSCs) pretreated by bFGF or BMP-2 in vitro and evaluated differential bone regeneration process induced by bFGF and BMP-2 loaded acellular dermal matrix (ADM) membrane using critical-size rat calvarial defect model in vivo. The results showed that the proliferation capability of BMMSCs pretreated by bFGF was stronger than that by BMP-2, while there was temporally differential effect of bFGF and BMP-2 pretreatment on MSC osteogenic differentiation potentials. During healing process of rat calvarial defects, 2-fold more CD34 −/CD90 + MSCs in group of bFGF-ADM was observed than in any other treatment group at 2 weeks. However, there were similar amount of new bone formation and expression of osteopotin in newly-formed bone tissue in groups of bFGF- and BMP-2-ADM at 8 weeks, which were more than those in ADM alone and blank control. Taken together, bFGF-ADM guided similar bone regeneration to BMP-2 through more efficient recruitment of MSCs, and moreover, BMMSCs pretreated by bFGF showed stronger proliferation at 1–5 days and osteogenic differentiation potentials at 14 days compared with BMP-2 pretreatment. - Highlights: • An improved barrier membrane used in the field of bone tissue engineering was proposed, which is acellular dermal matrix (ADM) loaded with growth factors. • It is generally agreed that BMP-2 and -7 provide the greatest bone regeneration potentials, however, we found that ADM loading with bFGF could guide similar bone regeneration to BMP-2. • Compared with BMP-2, bFGF could more effectively recruit MSCs and moreover, BMMSCs pretreated by bFGF showed out stronger proliferation at 1-5 days and osteogenic differentiation potentials at 14 days.

  3. Generation of an rhBMP-2-loaded beta-tricalcium phosphate/hydrogel composite and evaluation of its efficacy on peri-implant bone formation

    International Nuclear Information System (INIS)

    Lee, Jae Hyup; Baek, Hae-Ri; Lee, Ji-Ho; Ryu, Mi Young; Seo, Jun-Hyuk; Lee, Kyung-Mee

    2014-01-01

    Dental implant insertion on a site with low bone quality or bone defect should be preceded by a bone graft or artificial bone graft insertion to heal the defect. We generated a beta-tricalcium phosphate (β-TCP) and poloxamer 407-based hydrogel composite and penetration of the β-TCP/hydrogel composite into the peri-implant area of bone was evaluated by porous bone block experiments. The maximum penetration depth for porous bone blocks and dense bone blocks were 524 μm and 464 μm, respectively. We report the in-vivo performance of a composite of β-TCP/hydrogel composite as a carrier of recombinant human bone morphogenetic protein (rhBMP-2), implanted into a rabbit tibial defect model. Three holes drilled into each tibia of eight male rabbits were (1) grafted with dental implant fixtures; (2) filled with β-TCP/hydrogel composite (containing 5 μg of rhBMP-2), followed by grafting of the dental implant fixtures. Four weeks later, bone-implant contact ratio and peri-implant bone formation were analyzed by radiography, micro-CT and histology of undecalcified specimens. The micro-CT results showed a significantly higher level of trabecular thickness and new bone and peri-implant new bone formation in the experimental treatment compared to the control treatment. Histomorphometry revealed a significantly higher bone-implant contact ratio and peri-implant bone formation with the experimental treatment. The use of β-TCP/poloxamer 407 hydrogel composite as a carrier of rhBMP-2 significantly promoted new bone formation around the dental implant fixture and it also improved the quality of the new bone formed in the tibial marrow space. (paper)

  4. S100A4 and BMP-2 Co-Dependently Induce Vascular Smooth Muscle Cell Migration via pERK and Chloride Intracellular Channel 4 (CLIC4)

    Science.gov (United States)

    Spiekerkoetter, Edda; Guignabert, Christophe; de Jesus Perez, Vinicio; Alastalo, Tero-Pekka; Powers, Janine M; Wang, Lingli; Lawrie, Allan; Ambartsumian, Noona; Schmidt, Ann-Marie; Berryman, Mark; Ashley, Richard H; Rabinovitch, Marlene

    2009-01-01

    Rationale S100A4/Mts1 is implicated in motility of human pulmonary artery smooth muscle cells (hPASMC), through an interaction with the receptor for advanced glycation end products (RAGE). Objective We hypothesized that S100A4/Mts1-mediated hPASMC motility might be enhanced by loss of function of bone morphogenetic protein (BMP) receptor (R) II, observed in pulmonary arterial hypertension (PAH). Methods and Results Both S100A4/Mts1 (500ng/ml) and BMP-2 (10ng/ml) induce migration of hPASMCS in a novel co-dependent manner, in that the response to either ligand is lost with anti-RAGE or BMPRII siRNA. Phosphorylation of ERK is induced by both ligands and is required for motility by inducing MMP2 activity, but phosphoERK1/2 is blocked by anti-RAGE and not by BMPRII siRNA. In contrast, BMPRII siRNA, but not anti-RAGE, reduces expression of intracellular chloride channel 4 (CLIC4), a scaffolding molecule necessary for motility in response to S100A4/Mts1 or BMP-2. Reduced CLIC4 expression does not interfere with S100A4/Mts1 internalization or its interaction with myosin heavy chain IIA (MHCIIA), but does alter alignment of MHCIIA and actin filaments creating the appearance of vacuoles. This abnormality is associated with reduced peripheral distribution and/or delayed activation of RhoA and Rac1, small GTPases required for retraction and extension of lamellipodiae in motile cells. Conclusions Our studies demonstrate how a single ligand (BMP-2 or S100A4/Mts1) can recruit multiple cell surface receptors to relay signals that coordinate events culminating in a functional response, i.e., cell motility. We speculate that this carefully controlled process limits signals from multiple ligands, but could be subverted in disease. PMID:19713532

  5. Estudio del quitosano como biomaterial portador de rhBMP-2: desarrollo, caracterización y aplicabilidad en regeneración de tejido óseo

    OpenAIRE

    Abarrategi López, Ander

    2008-01-01

    La ingeniería de tejidos es un campo de investigación emergente y profundamente multidisciplinar. En esencia, esta disciplina busca nuevas terapias que permitan obtener tejido vivo y funcional, mediante un soporte activo, células y factores diferenciadores. En este contexto, el objetivo de este trabajo es aportar propiedades osteoinductivas a materiales implantables de uso clínico. Puesto que la rhBMP-2 es el factor osteodiferenciador más conocido, ésta proteína se sintetizó en el laboratorio...

  6. Preparation and physical characterization of calcium sulfate cement/silica-based mesoporous material composites for controlled release of BMP-2

    Directory of Open Access Journals (Sweden)

    Tan H

    2015-07-01

    Full Text Available Honglue Tan,1 Shengbing Yang,2 Pengyi Dai,1 Wuyin Li,1 Bing Yue2 1Luoyang Orthopedics and Traumatology Institution, Luoyang Orthopedic-Traumatological Hospital, Luoyang, 2Shanghai Key Laboratory of Orthopedic Implants, Department of Orthopedic Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China Abstract: As a commonly used implant material, calcium sulfate cement (CSC, has some shortcomings, including low compressive strength, weak osteoinduction capability, and rapid degradation. In this study, silica-based mesoporous materials such as SBA-15 were synthesized and combined with CSC to prepare CSC/SBA-15 composites. The properties of SBA-15 were characterized by X-ray diffraction, transmission electron microscopy, and nitrogen adsorption–desorption isotherms. SBA-15 was blended into CSC at 0, 5, 10, and 20 wt%, referred to as CSC, CSC-5S (5% mass ratio, CSC-10S (10% mass ratio, and CSC-20S (20% mass ratio, respectively. Fourier-transform infrared spectroscopy and compression tests were used to determine the structure and mechanical properties of the composites, respectively. The formation of hydroxyapatite on composite surfaces was analyzed using scanning electron microscopy and X-ray diffraction after soaking in simulated body fluid. BMP-2 was loaded into the composites by vacuum freeze-drying, and its release characteristics were detected by Bradford protein assay. The in vitro degradation of the CSC/SBA-15 composite was investigated by measuring weight loss. The results showed that the orderly, nanostructured, mesoporous SBA-15 possessed regular pore size and structure. The compressive strength of CSC/SBA-15 increased with the increase in SBA-15 mass ratio, and CSC-20S demonstrated the maximum strength. Compared to CSC, hydroxyapatite that formed on the surfaces of CSC/SBA-15 was uniform and compact. The degradation rate of CSC/SBA-15 decreased with increasing

  7. Spatial control of bone formation using a porous polymer scaffold co-delivering anabolic rhBMP-2 and anti-resorptive agents

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    NYC Yu

    2014-01-01

    Full Text Available Current clinical delivery of recombinant human bone morphogenetic proteins (rhBMPs utilises freeze-dried collagen. Despite effective new bone generation, rhBMP via collagen can be limited by significant complications due to inflammation and uncontrolled bone formation. This study aimed to produce an alternative rhBMP local delivery system to permit more controllable and superior rhBMP-induced bone formation. Cylindrical porous poly(lactic-co-glycolic acid (PLGA scaffolds were manufactured by thermally-induced phase separation. Scaffolds were encapsulated with anabolic rhBMP-2 (20 µg ± anti-resorptive agents: zoledronic acid (5 µg ZA, ZA pre-adsorbed onto hydroxyapatite microparticles, (5 µg ZA/2 % HA or IkappaB kinase (IKK inhibitor (10 µg PS-1145. Scaffolds were inserted in a 6-mm critical-sized femoral defect in Wistar rats, and compared against rhBMP-2 via collagen. The regenerate region was examined at 6 weeks by 3D microCT and descriptive histology. MicroCT and histology revealed rhBMP-induced bone was more restricted in the PLGA scaffolds than collagen scaffolds (-92.3 % TV, p < 0.01. The regenerate formed by PLGA + rhBMP-2/ZA/HA showed comparable bone volume to rhBMP-2 via collagen, and bone mineral density was +9.1 % higher (p < 0.01. Local adjunct ZA/HA or PS-1145 significantly enhanced PLGA + rhBMP-induced bone formation by +78.2 % and +52.0 %, respectively (p ≤ 0.01. Mechanistically, MG-63 human osteoblast-like cells showed cellular invasion and proliferation within PLGA scaffolds. In conclusion, PLGA scaffolds enabled superior spatial control of rhBMP-induced bone formation over clinically-used collagen. The PLGA scaffold has the potential to avoid uncontrollable bone formation-related safety issues and to customise bone shape by scaffold design. Moreover, local treatment with anti-resorptive agents incorporated within the scaffold further augmented rhBMP-induced bone formation.

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

    Science.gov (United States)

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

    2017-07-01

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

  9. Continuity resection of the mandible after ameloblastoma - feasibility of oral rehabilitation with rhBMP-2 associated to bovine xenograft followed by implant installation.

    Science.gov (United States)

    Lustosa, Romulo Maciel; Macedo, Diogo de Vasconcelos; Iwaki, Lilian Cristina Vessoni; Tolentino, Elen de Souza; Hasse, Paulo Norberto; Marson, Giordano Bruno de Oliveira; Iwaki Filho, Liogi

    2015-10-01

    Recombinant human morphogenetic protein (rhBMP) is a graft alternative for extensive mandibular reconstruction after tumor resections. However, the feasibility of rhBMP-2 to receive osseointegrated implants and prosthetic rehabilitation has been rarely reported. This study reports on a case of an extensive solid ameloblastoma along the mandibular body. The treatment consisted of resection followed by off-label use of rhBMP type 2 associated with bovine bone xenograft. Eleven months postoperatively, the patient was prosthetically rehabilitated with dental implants, without evidence of resorption or complications. The literature on mandibular reconstructions using rhBMP and their feasibility for future osseointegrated implant placement was also reviewed. Based on the presented case, the association between rhBMP-2 and a bovine bone xenograft could be considered a feasible option for the reconstruction and rehabilitation of large mandibular defects after tumor resection. According to the literature, the use of rhBMP as a graft material is encouraging, with good clinical outcome. However, there are no long-term studies demonstrating success and survival rates of implants placed in these grafts. Future investigations will be required to ascertain the long-term survival of implants in areas grafted with rhBMP. Also, there is a lack of information regarding the prosthetic rehabilitation of these patients. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  10. Bone morphogenetic protein-2 (BMP-2 and transforming growth factor-β1 (TGF-β1 alter connexin 43 phosphorylation in MC3T3-E1 Cells

    Directory of Open Access Journals (Sweden)

    Rudkin George H

    2001-07-01

    Full Text Available Abstract Background Bone morphogenetic proteins (BMPs and transforming growth factor-βs (TGF-βs are important regulators of bone repair and regeneration. BMP-2 and TGF-β1 have been shown to inhibit gap junctional intercellular communication (GJIC in MC3T3-E1 cells. Connexin 43 (Cx43 has been shown to mediate GJIC in osteoblasts and it is the predominant gap junctional protein expressed in these murine osteoblast-like cells. We examined the expression, phosphorylation, and subcellular localization of Cx43 after treatment with BMP-2 or TGF-β1 to investigate a possible mechanism for the inhibition of GJIC. Results Northern blot analysis revealed no detectable change in the expression of Cx43 mRNA. Western blot analysis demonstrated no significant change in the expression of total Cx43 protein. However, significantly higher ratios of unphosphorylated vs. phosphorylated forms of Cx43 were detected after BMP-2 or TGF-β1 treatment. Immunofluorescence and cell protein fractionation revealed no detectable change in the localization of Cx43 between the cytosol and plasma membrane. Conclusions BMP-2 and TGF-β1 do not alter expression of Cx43 at the mRNA or protein level. BMP-2 and TGF-β1 may inhibit GJIC by decreasing the phosphorylated form of Cx43 in MC3T3-E1 cells.

  11. Neurotrophin-3 Induces BMP-2 and VEGF Activities and Promotes the Bony Repair of Injured Growth Plate Cartilage and Bone in Rats.

    Science.gov (United States)

    Su, Yu-Wen; Chung, Rosa; Ruan, Chun-Sheng; Chim, Shek Man; Kuek, Vincent; Dwivedi, Prem P; Hassanshahi, Mohammadhossein; Chen, Ke-Ming; Xie, Yangli; Chen, Lin; Foster, Bruce K; Rosen, Vicki; Zhou, Xin-Fu; Xu, Jiake; Xian, Cory J

    2016-06-01

    Injured growth plate is often repaired by bony tissue causing bone growth defects, for which the mechanisms remain unclear. Because neurotrophins have been implicated in bone fracture repair, here we investigated their potential roles in growth plate bony repair in rats. After a drill-hole injury was made in the tibial growth plate and bone, increased injury site mRNA expression was observed for neurotrophins NGF, BDNF, NT-3, and NT-4 and their Trk receptors. NT-3 and its receptor TrkC showed the highest induction. NT-3 was localized to repairing cells, whereas TrkC was observed in stromal cells, osteoblasts, and blood vessel cells at the injury site. Moreover, systemic NT-3 immunoneutralization reduced bone volume at injury sites and also reduced vascularization at the injured growth plate, whereas recombinant NT-3 treatment promoted bony repair with elevated levels of mRNA for osteogenic markers and bone morphogenetic protein (BMP-2) and increased vascularization and mRNA for vascular endothelial growth factor (VEGF) and endothelial cell marker CD31 at the injured growth plate. When examined in vitro, NT-3 promoted osteogenesis in rat bone marrow stromal cells, induced Erk1/2 and Akt phosphorylation, and enhanced expression of BMPs (particularly BMP-2) and VEGF in the mineralizing cells. It also induced CD31 and VEGF mRNA in rat primary endothelial cell culture. BMP activity appears critical for NT-3 osteogenic effect in vitro because it can be almost completely abrogated by co-addition of the BMP inhibitor noggin. Consistent with its angiogenic effect in vivo, NT-3 promoted angiogenesis in metatarsal bone explants, an effect abolished by co-treatment with anti-VEGF. This study suggests that NT-3 may be an osteogenic and angiogenic factor upstream of BMP-2 and VEGF in bony repair, and further studies are required to investigate whether NT-3 may be a potential target for preventing growth plate faulty bony repair or for promoting bone fracture healing. © 2016

  12. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    OpenAIRE

    Bae, Ji Cheol; Lee, Jin-Ju; Shim, Jin-Hyung; Park, Keun-Ho; Lee, Jeong-Seok; Bae, Eun-Bin; Choi, Jae-Won; Huh, Jung-Bo

    2017-01-01

    In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent an...

  13. Characteristics and stimulation potential with BMP-2 and BMP-7 of tenocyte-like cells isolated from the rotator cuff of female donors.

    Directory of Open Access Journals (Sweden)

    Franka Klatte-Schulz

    Full Text Available Tendon bone healing of the rotator cuff is often associated with non-healing or recurrent defects, which seems to be influenced by the patient's age and sex. The present study aims to examine cellular biological characteristics of tenocyte-like cells that may contribute to this impaired rotator cuff healing. Moreover, a therapeutic approach using growth factors could possibly stimulate tendon bone healing. Therefore, our second aim was to identify patient groups who would particularly benefit from growth factor stimulation. Tenocyte-like cells isolated from supraspinatus tendons of female donors younger and older than 65 years of age were characterized with respect to different cellular biological parameters, such as cell density, cell count, marker expression, collagen-I protein synthesis, and stem cell potential. Furthermore, cells of the donor groups were stimulated with BMP-2 and BMP-7 (200 and 1000 ng/ml in 3D-culture and analyzed for cell count, marker expression and collagen-I protein synthesis. Female donors older than 65 years of age showed significantly decreased cell count and collagen-I protein synthesis compared to cells from donors younger than 65 years. Cellular biological parameters including cell count, collagen-I and -III expression, and collagen-I protein synthesis of cells from both donor groups were stimulated with BMP-2 and BMP-7. The cells from donors older than 65 years revealed a decreased stimulation potential for cell count compared to the younger group. Cells from female donors older than 65 years of age showed inferior cellular biological characteristics. This may be one reason for a weaker healing potential observed in older female patients and should be taken into consideration for tendon bone healing of the rotator cuff.

  14. Ancestral regulatory circuits governing ectoderm patterning downstream of Nodal and BMP2/4 revealed by gene regulatory network analysis in an echinoderm.

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    Alexandra Saudemont

    2010-12-01

    Full Text Available Echinoderms, which are phylogenetically related to vertebrates and produce large numbers of transparent embryos that can be experimentally manipulated, offer many advantages for the analysis of the gene regulatory networks (GRN regulating germ layer formation. During development of the sea urchin embryo, the ectoderm is the source of signals that pattern all three germ layers along the dorsal-ventral axis. How this signaling center controls patterning and morphogenesis of the embryo is not understood. Here, we report a large-scale analysis of the GRN deployed in response to the activity of this signaling center in the embryos of the Mediterranean sea urchin Paracentrotus lividus, in which studies with high spatial resolution are possible. By using a combination of in situ hybridization screening, overexpression of mRNA, recombinant ligand treatments, and morpholino-based loss-of-function studies, we identified a cohort of transcription factors and signaling molecules expressed in the ventral ectoderm, dorsal ectoderm, and interposed neurogenic ("ciliary band" region in response to the known key signaling molecules Nodal and BMP2/4 and defined the epistatic relationships between the most important genes. The resultant GRN showed a number of striking features. First, Nodal was found to be essential for the expression of all ventral and dorsal marker genes, and BMP2/4 for all dorsal genes. Second, goosecoid was identified as a central player in a regulatory sub-circuit controlling mouth formation, while tbx2/3 emerged as a critical factor for differentiation of the dorsal ectoderm. Finally, and unexpectedly, a neurogenic ectoderm regulatory circuit characterized by expression of "ciliary band" genes was triggered in the absence of TGF beta signaling. We propose a novel model for ectoderm regionalization, in which neural ectoderm is the default fate in the absence of TGF beta signaling, and suggest that the stomodeal and neural subcircuits that we

  15. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Directory of Open Access Journals (Sweden)

    Ji Cheol Bae

    2017-12-01

    Full Text Available In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL/β-tricalcium phosphate (β-TCP/bone decellularized extracellular matrix (bdECM scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, % but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %. Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results.

  16. Development and Assessment of a 3D-Printed Scaffold with rhBMP-2 for an Implant Surgical Guide Stent and Bone Graft Material: A Pilot Animal Study

    Science.gov (United States)

    Bae, Ji Cheol; Lee, Jin-Ju; Shim, Jin-Hyung; Park, Keun-Ho; Lee, Jeong-Seok; Bae, Eun-Bin; Choi, Jae-Won; Huh, Jung-Bo

    2017-01-01

    In this study, a new concept of a 3D-printed scaffold was introduced for the accurate placement of an implant and the application of a recombinant human bone morphogenetic protein-2 (rhBMP-2)-loaded bone graft. This preliminary study was conducted using two adult beagles to evaluate the 3D-printed polycaprolactone (PCL)/β-tricalcium phosphate (β-TCP)/bone decellularized extracellular matrix (bdECM) scaffold conjugated with rhBMP-2 for the simultaneous use as an implant surgical guide stent and bone graft material that promotes new bone growth. Teeth were extracted from the mandible of the beagle model and scanned by computed tomography (CT) to fabricate a customized scaffold that would fit the bone defect. After positioning the implant guide scaffold, the implant was placed and rhBMP-2 was injected into the scaffold of the experimental group. The two beagles were sacrificed after three months. The specimen block was obtained and scanned by micro-CT. Histological analysis showed that the control and experimental groups had similar new bone volume (NBV, %) but the experimental group with BMP exhibited a significantly higher bone-to-implant contact ratio (BIC, %). Within the limitations of this preliminary study, a 3D-printed scaffold conjugated with rhBMP-2 can be used simultaneously as an implant surgical guide and a bone graft in a large bone defect site. Further large-scale studies will be needed to confirm these results. PMID:29258172

  17. Dynamic MR imaging: Follow-up study after femoral head core decompression and rhBMP-2 instillation in patients with avascular necrosis of the femoral head; Dynamische Magnetresonanztomographie (MRT): Verlaufsbeobachtung nach Femurkerndekompression und Auffuellung mit rekombinantem, humanem Bone morphogenetic Protein-2 (rhBMP-2) bei avaskulaerer Femurkopfnekrose

    Energy Technology Data Exchange (ETDEWEB)

    Schedel, H. [Klinik Prof. Schedel, Kellberg (Germany); Schneller, A. [Humboldt-Universitaet, Berlin (Germany). Klinik fuer Allgemein- und Transplantationschirurgie; Vogl, T.; Mueller, H.F.; Maeurer, J.; Felix, R. [Humboldt-Universitaet, Berlin (Germany). Strahlenklinik und Poliklinik; Suedkamp, N. [Humboldt-Universitaet, Berlin (Germany). Unfall- und Wiederherstellungschirurgie; Eisenschenk, A. [Freie Univ. Berlin (Germany). Orthopaedische Klinik und Poliklinik

    2000-07-01

    Material and Methods: Six patients with avascular necrosis of the femoral head ARCO-stage I- or II-lesions were treated surgically by femoral head core decompression. Three of these patients were additionally treated with rhBMP-2-instillation. The progression or regression could be confirmed by T1- and T2-weighted spinecho-sequences (zero, four, ten, sixteen weeks and 24 months follow up). Results: Corresponding ARCO-classification with partly more sensitive measurement of vitality signs in comparison to the optical X-ray classification. The objective, quantitative measurement of signalintensity post contrast medium reduces the influence of experience and level of education. The dynamic sequences results are reproducable. (orig.) [German] Material und Methoden: Sechs Patienten mit avaskulaerer Nekrose des Femurkopfes des Stadiums I oder II nach ARCO wurden einer Femurkerndekompression unterzogen. Drei dieser Patienten erhielten zusaetzlich eine rhBMP-2-Auffuellung. Zum Zeitpunkt null, vier, zehn, sechszehn Wochen und 24 Monaten post OP erfolgte die kernspintomographische Untersuchung mit T1- und T2-gewichteten Sequenzen unter besonderer Beruecksichtigung der dynamischen Untersuchungssequenz nach Gabe von Gd-DTPA (Gadopentetsaeure, Dimegluminsalz; Magnevist {sup trademark}) zur Dokumentation der Signalintensitaetssteigerung pro Zeiteinheit in der Nekroseregion. Ergebnisse: Uebereinstimmende Stadienklassifikation nach ARCO mit zum Teil empfindlicherer Messung von Vitalitaetszeichen im Vergleich zu rein visuellen roentgenologischen Einteilung. Die objektive, quantitative Messung des Signalintensitaetssteigerungsverhaltens nach Kontrastmittelgabe im Bereich der Femurkopfnekrose kann den Einfluss von subjektiven Eigenschaften des Untersuchers (Erfahrung, Ausbildungsstand) reduzieren, wobei die Ergebnisse der Dynamiksequenzen objektiv reproduzierbar sind. (orig.)

  18. Enhanced angiogenesis and osteogenesis in critical bone defects by the controlled release of BMP-2 and VEGF: implantation of electron beam melting-fabricated porous Ti6Al4V scaffolds incorporating growth factor-doped fibrin glue

    International Nuclear Information System (INIS)

    Lv, Jia; Xiu, Peng; Tan, Jie; Cai, Hong; Liu, Zhongjun; Jia, Zhaojun

    2015-01-01

    Electron beam melting (EBM)-fabricated porous titanium implants possessing low elastic moduli and tailored structures are promising biomaterials for orthopedic applications. However, the bio-inert nature of porous titanium makes reinforcement with growth factors (GFs) a promising method to enhance implant in vivo performance. Bone-morphogenic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) are key factors of angiogenesis and osteogenesis. Therefore, the present study is aimed at evaluating EBM-fabricated porous titanium implants incorporating GF-doped fibrin glue (FG) as composite scaffolds providing GFs for improvement of angiogenesis and osteogenesis in rabbit femoral condyle defects. BMP-2 and VEGF were added into the constituent compounds of FG, and then this GF-doped FG was subsequently injected into the porous scaffolds. In five groups of implants, angiogenesis and osteogenesis were evaluated at 4 weeks post-implantation using Microfil perfusion and histological analysis: eTi (empty scaffolds), cTi (containing undoped FG), BMP/cTi (containing 50 μg rhBMP-2), VEGF/cTi (containing 0.5 μg VEGF) and Dual/cTi (containing 50 μg rhBMP-2 and 0.5 μg VEGF). The results demonstrate that these composite implants are biocompatible and provide the desired gradual release of the bioactive growth factors. Incorporation of GF delivery, whether a single factor or dual factors, significantly enhanced both angiogenesis and osteogenesis inside the porous scaffolds. However, the synergistic effect of the dual factors combination was observable on angiogenesis but absent on osteogenesis. In conclusion, fibrin glue is a biocompatible material that could be employed as a delivery vehicle in EBM-fabricated porous titanium for controlled release of BMP-2 and VEGF. Application of this method for loading a porous titanium scaffold to incorporate growth factors is a convenient and promising strategy for improving osteogenesis of critical-sized bone defects

  19. Breast cancer cells obtain an osteomimetic feature via epithelial-mesenchymal transition that have undergone BMP2/RUNX2 signaling pathway induction.

    Science.gov (United States)

    Tan, Cong-Cong; Li, Gui-Xi; Tan, Li-Duan; Du, Xin; Li, Xiao-Qing; He, Rui; Wang, Qing-Shan; Feng, Yu-Mei

    2016-11-29

    Bone is one of the most common organs of breast cancer metastasis. Cancer cells that mimic osteoblasts by expressing bone matrix proteins and factors have a higher likelihood of metastasizing to bone. However, the molecular mechanisms of osteomimicry formation of cancer cells remain undefined. Herein, we identified a set of bone-related genes (BRGs) that are ectopically co-expressed in primary breast cancer tissues and determined that osteomimetic feature is obtained due to the osteoblast-like transformation of epithelial breast cancer cells that have undergone epithelial-mesenchymal transition (EMT) followed by bone morphogenetic protein-2 (BMP2) stimulation. Furthermore, we demonstrated that breast cancer cells that transformed into osteoblast-like cells with high expression of BRGs showed enhanced chemotaxis, adhesion, proliferation and multidrug resistance in an osteoblast-mimic bone microenvironment in vitro. During these processes, runt-related transcription factor 2 (RUNX2) functioned as a master mediator by suppressing or activating the transcription of BRGs that underlie the dynamic antagonism between the TGF-β/SMAD and BMP/SMAD signaling pathways in breast cancer cells. Our findings suggest a novel mechanism of osteomimicry formation that arises in primary breast tumors, which may explain the propensity of breast cancer to metastasize to the skeleton and contribute to potential strategies for predicting and targeting breast cancer bone metastasis and multidrug resistance.

  20. BMP-2, hypoxia, and COL1A1/HtrA1 siRNAs favor neo-cartilage hyaline matrix formation in chondrocytes.

    Science.gov (United States)

    Ollitrault, David; Legendre, Florence; Drougard, Carole; Briand, Mélanie; Benateau, Hervé; Goux, Didier; Chajra, Hanane; Poulain, Laurent; Hartmann, Daniel; Vivien, Denis; Shridhar, Vijayalakshmi; Baldi, Alfonso; Mallein-Gerin, Frédéric; Boumediene, Karim; Demoor, Magali; Galera, Philippe

    2015-02-01

    Osteoarthritis (OA) is an irreversible pathology that causes a decrease in articular cartilage thickness, leading finally to the complete degradation of the affected joint. The low spontaneous repair capacity of cartilage prevents any restoration of the joint surface, making OA a major public health issue. Here, we developed an innovative combination of treatment conditions to improve the human chondrocyte phenotype before autologous chondrocyte implantation. First, we seeded human dedifferentiated chondrocytes into a collagen sponge as a scaffold, cultured them in hypoxia in the presence of a bone morphogenetic protein (BMP), BMP-2, and transfected them with small interfering RNAs targeting two markers overexpressed in OA dedifferentiated chondrocytes, that is, type I collagen and/or HtrA1 serine protease. This strategy significantly decreased mRNA and protein expression of type I collagen and HtrA1, and led to an improvement in the chondrocyte phenotype index of differentiation. The effectiveness of our in vitro culture process was also demonstrated in the nude mouse model in vivo after subcutaneous implantation. We, thus, provide here a new protocol able to favor human hyaline chondrocyte phenotype in primarily dedifferentiated cells, both in vitro and in vivo. Our study also offers an innovative strategy for chondrocyte redifferentiation and opens new opportunities for developing therapeutic targets.

  1. The influence of Aloe vera and xenograft XCB toward of bone morpho protein 2 BMP2 expression and amount of osteoblast of alveolar bone induced into tooth extraction sockets Cavia cobaya

    Directory of Open Access Journals (Sweden)

    Utari Kresnoadi

    2014-12-01

    Full Text Available Tooth extraction can cause inflammation leading to alveolar ridge resorption. In addition, prominent ridge has crucial role for making denture su-ccessfully. Thus, socket preservation is needed to prevent greater alveolar ridge resorption. An innovative material, a combination of Aloe vera and xe-nograft (XCB, is then considered as a biogenic stimulator that can reduce inflammation, as a result, the growth of alveolar bone is expected to be impro-ved. This research is aimed to prove whether the mixture of Aloe vera and xenograft can stimulate BMP2 and increase osteoblasts. Forty-eight Cavia co-baya animals were divided into eight groups each of which consisted of six animals. The mandibular incisors of those Cavia cobaya animals were then extracted and filled with PEG as Group Control, XCB as Group XCB, Aloe vera as Group Aloe vera, and a combination of Aloe vera +XCB as Group Aloe vera +XCB. Next, the first four groups were sacrificed seven days after extraction, and the second four groups were sacrificed 30 days after extrac-tion. And then, immunohistochemical and histopathology examinations were conducted to examine BMP2 expression and osteoblasts. Based on the re-sult known that the mixture of Aloe vera and xenograft can increase BMP2 expression and amount of osteoblasts. It can be concluded that the mixture of Aloe vera and xenograft can increase BMP2 expression and amount of osteoblast cel . It can be used as an alternative material to increase the growth of alveolar bone after extraction.

  2. Histological and radiographic evaluation of the muscle tissue of rats after implantation of bone morphogenic protein (rhBMP-2 in a scaffold of inorganic bone and after stimulation with low-power laser light

    Directory of Open Access Journals (Sweden)

    Bengtson Antonio

    2010-01-01

    Full Text Available Objective: The present study histologically and radiologically evaluates the muscle tissue of rats after implantation of bone morphogenic protein (rhBMP-2 in a natural inorganic bone mineral scaffold from a bull calf femur and irradiation with low-power light laser. Materials and Methods: The right and left hind limbs of 16 rats were shaved and an incision was made in the muscle on the face corresponding to the median portion of the tibia, into which rhBMP-2 in a scaffold of inorganic bone was implanted. Two groups of limbs were formed: control (G1 and laser irradiation (G2. G2 received diode laser light applied in the direction of the implant, at a dose of 8 J/cm2 for three minutes. On the 7th, 21st, 40th and 112th days after implantation, hind limbs of 4 animals were radiographed and their implants removed together with the surrounding tissue for study under the microscope. The histological results were graded as 0=absence, 1=slight presence, 2=representative and 3=very representative, with regard to the following events: formation of osteoid structure, acute inflammation, chronic inflammation, fibrin deposition, neovascularization, foreign-body granuloma and fibrosis. Results: There were no statistically significant differences in these events at each evaluation times, between the two groups (P > 0.05; Mann-Whitney test. Nevertheless, it could be concluded that the natural inorganic bone matrix with rhBMP-2, from the femur of a bull calf, is a biocompatible combination. Conclusions: Under these conditions, the inductive capacity of rhBMP-2 for cell differentiation was inhibited. There was a slight acceleration in tissue healing in the group that received irradiation with low-power laser light.

  3. Influence of Poly(L-Lactic Acid Nanofibers and BMP-2–Containing Poly(L-Lactic Acid Nanofibers on Growth and Osteogenic Differentiation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Markus D. Schofer

    2008-01-01

    Full Text Available The aim of this study was to characterize synthetic poly-(L-lactic acid (PLLA nanofibers concerning their ability to promote growth and osteogenic differentiation of stem cells in vitro, as well as to test their suitability as a carrier system for growth factors. Fiber matrices composed of PLLA or BMP-2–incorporated PLLA were seeded with human mesenchymal stem cells and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of alkaline phosphatase (ALP, osteocalcin (OC, and collagen I (COL-I. Furthermore, COL-I and OC deposition, as well as cell densities and proliferation, were analyzed using fluorescence microscopy. Although the presence of nanofibers diminished the dexamethasone-induced proliferation, there were no differences in cell densities or deposition of either COL-I or OC after 22 days of culture. The gene expression of ALP, OC, and COL-I decreased in the initial phase of cell cultivation on PLLA nanofibers as compared to cover slip control, but normalized during the course of cultivation. The initial down-regulation was not observed when BMP-2 was directly incorporated into PLLA nanofibers by electrospinning, indicating that growth factors like BMP-2 might survive the spinning process in a bioactive form.

  4. Influence of Poly(L-Lactic Acid) Nanofibers and BMP-2–Containing Poly(L-Lactic Acid) Nanofibers on Growth and Osteogenic Differentiation of Human Mesenchymal Stem Cells

    Science.gov (United States)

    Schofer, Markus D.; Fuchs-Winkelmann, Susanne; Gräbedünkel, Christian; Wack, Christina; Dersch, Roland; Rudisile, Markus; Wendorff, Joachim H.; Greiner, Andreas; Paletta, Jürgen R. J.; Boudriot, Ulrich

    2008-01-01

    The aim of this study was to characterize synthetic poly-(L-lactic acid) (PLLA) nanofibers concerning their ability to promote growth and osteogenic differentiation of stem cells in vitro, as well as to test their suitability as a carrier system for growth factors. Fiber matrices composed of PLLA or BMP-2–incorporated PLLA were seeded with human mesenchymal stem cells and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of alkaline phosphatase (ALP), osteocalcin (OC), and collagen I (COL-I). Furthermore, COL-I and OC deposition, as well as cell densities and proliferation, were analyzed using fluorescence microscopy. Although the presence of nanofibers diminished the dexamethasone-induced proliferation, there were no differences in cell densities or deposition of either COL-I or OC after 22 days of culture. The gene expression of ALP, OC, and COL-I decreased in the initial phase of cell cultivation on PLLA nanofibers as compared to cover slip control, but normalized during the course of cultivation. The initial down-regulation was not observed when BMP-2 was directly incorporated into PLLA nanofibers by electrospinning, indicating that growth factors like BMP-2 might survive the spinning process in a bioactive form. PMID:19112539

  5. A heterozygous microdeletion of 20p12.2-3 encompassing PROKR2 and BMP2 in a patient with congenital hypopituitarism and growth hormone deficiency.

    Science.gov (United States)

    Parsons, Samuel J H; Wright, Neville B; Burkitt-Wright, Emma; Skae, Mars S; Murray, Phillip G

    2017-08-01

    Congenital growth hormone deficiency is a rare disorder with an incidence of approximately 1 in 4,000 live births. Pituitary development is under the control of a multitude of spatiotemporally regulated signaling molecules and transcription factors. Mutations in the genes encoding these molecules can result in hypopituitarism but for the majority of children with congenital hypopituitarism, the aetiology of their disease remains unknown. The proband is a 5-year-old girl who presented with neonatal hypoglycaemia and prolonged jaundice. No definitive endocrine cause of hypoglycaemia was identified in the neonatal period. She was born of normal size at 42 weeks but demonstrated growth failure with a progressive reduction in height to -3.2 SD by age 4.5 years and failed a growth hormone stimulation test with a peak growth hormone of 4.2 mcg/L. MRI of the pituitary gland demonstrated a hypoplastic anterior lobe and ectopic posterior lobe. Array CGH demonstrated an inherited 0.2 Mb gain at 1q21.1 and a de novo 4.8 Mb heterozygous deletion at 20p12.2-3. The deletion contained 17 protein coding genes including PROKR2 and BMP2, both of which are expressed during embryological development of the pituitary gland. PROKR2 mutations have been associated with hypopituitarism but a heterozygous deletion of this gene with hypopituitarism is a novel observation. In conclusion, congenital hypopituitarism can be present in individuals with a 20p12.3 deletion, observed with incomplete penetrance. Array CGH may be a useful investigation in select cases of early onset growth hormone deficiency, and patients with deletions within this region should be evaluated for pituitary hormone deficiencies. © 2017 Wiley Periodicals, Inc.

  6. Effective Inhibition of Bone Morphogenetic Protein Function by Highly Specific Llama-Derived Antibodies.

    Science.gov (United States)

    Calpe, Silvia; Wagner, Koen; El Khattabi, Mohamed; Rutten, Lucy; Zimberlin, Cheryl; Dolk, Edward; Verrips, C Theo; Medema, Jan Paul; Spits, Hergen; Krishnadath, Kausilia K

    2015-11-01

    Bone morphogenetic proteins (BMP) have important but distinct roles in tissue homeostasis and disease, including carcinogenesis and tumor progression. A large number of BMP inhibitors are available to study BMP function; however, as most of these antagonists are promiscuous, evaluating specific effects of individual BMPs is not feasible. Because the oncogenic role of the different BMPs varies for each neoplasm, highly selective BMP inhibitors are required. Here, we describe the generation of three types of llama-derived heavy chain variable domains (VHH) that selectively bind to either BMP4, to BMP2 and 4, or to BMP2, 4, 5, and 6. These generated VHHs have high affinity to their targets and are able to inhibit BMP signaling. Epitope binning and docking modeling have shed light into the basis for their BMP specificity. As opposed to the wide structural reach of natural inhibitors, these small molecules target the grooves and pockets of BMPs involved in receptor binding. In organoid experiments, specific inhibition of BMP4 does not affect the activation of normal stem cells. Furthermore, in vitro inhibition of cancer-derived BMP4 noncanonical signals results in an increase of chemosensitivity in a colorectal cancer cell line. Therefore, because of their high specificity and low off-target effects, these VHHs could represent a therapeutic alternative for BMP4(+) malignancies. ©2015 American Association for Cancer Research.

  7. Bone regeneration in critical bone defects using three-dimensionally printed β-tricalcium phosphate/hydroxyapatite scaffolds is enhanced by coating scaffolds with either dipyridamole or BMP-2.

    Science.gov (United States)

    Ishack, Stephanie; Mediero, Aranzazu; Wilder, Tuere; Ricci, John L; Cronstein, Bruce N

    2017-02-01

    Bone defects resulting from trauma or infection need timely and effective treatments to restore damaged bone. Using specialized three-dimensional (3D) printing technology we have created custom 3D scaffolds of hydroxyapatite (HA)/beta-tri-calcium phosphate (β-TCP) to promote bone repair. To further enhance bone regeneration we have coated the scaffolds with dipyridamole, an agent that increases local adenosine levels by blocking cellular uptake of adenosine. Nearly 15% HA:85% β-TCP scaffolds were designed using Robocad software, fabricated using a 3D Robocasting system, and sintered at 1100°C for 4 h. Scaffolds were coated with BMP-2 (200 ng mL -1 ), dypiridamole 100 µM or saline and implanted in C57B6 and adenosine A2A receptor knockout (A2AKO) mice with 3 mm cranial critical bone defects for 2-8 weeks. Dipyridamole release from scaffold was assayed spectrophotometrically. MicroCT and histological analysis were performed. Micro-computed tomography (microCT) showed significant bone formation and remodeling in HA/β-TCP-dipyridamole and HA/β-TCP-BMP-2 scaffolds when compared to scaffolds immersed in vehicle at 2, 4, and 8 weeks (n = 5 per group; p ≤ 0.05, p ≤ 0.05, and p ≤ 0.01, respectively). Histological analysis showed increased bone formation and a trend toward increased remodeling in HA/β-TCP- dipyridamole and HA/β-TCP-BMP-2 scaffolds. Coating scaffolds with dipyridamole did not enhance bone regeneration in A2AKO mice. In conclusion, scaffolds printed with HA/β-TCP promote bone regeneration in critical bone defects and coating these scaffolds with agents that stimulate A2A receptors and growth factors can further enhance bone regeneration. These coated scaffolds may be very useful for treating critical bone defects due to trauma, infection or other causes. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 366-375, 2017. © 2015 Wiley Periodicals, Inc.

  8. Autologous serum improves bone formation in a primary stable silica-embedded nanohydroxyapatite bone substitute in combination with mesenchymal stem cells and rhBMP-2 in the sheep model

    Directory of Open Access Journals (Sweden)

    Boos AM

    2014-11-01

    Full Text Available Anja M Boos,1,* Annika Weigand,1,* Gloria Deschler,1 Thomas Gerber,2 Andreas Arkudas,1 Ulrich Kneser,1 Raymund E Horch,1 Justus P Beier11Department of Plastic and Hand Surgery, University Hospital of Erlangen, Friedrich-Alexander-University of Erlangen-Nürnberg FAU, Erlangen, 2Institute of Physics, University of Rostock, Rostock, Germany *These authors contributed equally to this work Abstract: New therapeutic strategies are required for critical size bone defects, because the gold standard of transplanting autologous bone from an unharmed area of the body often leads to several severe side effects and disadvantages for the patient. For years, tissue engineering approaches have been seeking a stable, axially vascularized transplantable bone replacement suitable for transplantation into the recipient bed with pre-existing insufficient conditions. For this reason, the arteriovenous loop model was developed and various bone substitutes have been vascularized. However, it has not been possible thus far to engineer a primary stable and axially vascularized transplantable bone substitute. For that purpose, a primary stable silica-embedded nanohydroxyapatite (HA bone substitute in combination with blood, bone marrow, expanded, or directly retransplanted mesenchymal stem cells, recombinant human bone morphogenetic protein 2 (rhBMP-2, and different carrier materials (fibrin, cell culture medium, autologous serum was tested subcutaneously for 4 or 12 weeks in the sheep model. Autologous serum lead to an early matrix change during degradation of the bone substitute and formation of new bone tissue. The best results were achieved in the group combining mesenchymal stem cells expanded with 60 µg/mL rhBMP-2 in autologous serum. Better ingrowth of fibrovascular tissue could be detected in the autologous serum group compared with the control (fibrin. Osteoclastic activity indicating an active bone remodeling process was observed after 4 weeks, particularly

  9. Characterization and use of Equine Bone Marrow Mesenchymal Stem Cells in Equine Cartilage Engineering. Study of their Hyaline Cartilage Forming Potential when Cultured under Hypoxia within a Biomaterial in the Presence of BMP-2 and TGF-ß1.

    Science.gov (United States)

    Branly, Thomas; Bertoni, Lélia; Contentin, Romain; Rakic, Rodolphe; Gomez-Leduc, Tangni; Desancé, Mélanie; Hervieu, Magalie; Legendre, Florence; Jacquet, Sandrine; Audigié, Fabrice; Denoix, Jean-Marie; Demoor, Magali; Galéra, Philippe

    2017-10-01

    Articular cartilage presents a poor capacity for self-repair. Its structure-function are frequently disrupted or damaged upon physical trauma or osteoarthritis in humans. Similar musculoskeletal disorders also affect horses and are the leading cause of poor performance or early retirement of sport- and racehorses. To develop a therapeutic solution for horses, we tested the autologous chondrocyte implantation technique developed on human bone marrow (BM) mesenchymal stem cells (MSCs) on horse BM-MSCs. This technique involves BM-MSC chondrogenesis using a combinatory approach based on the association of 3D-culture in collagen sponges, under hypoxia in the presence of chondrogenic factors (BMP-2 + TGF-β 1 ) and siRNA to knockdown collagen I and HtrA1. Horse BM-MSCs were characterized before being cultured in chondrogenic conditions to find the best combination to enhance, stabilize, the chondrocyte phenotype. Our results show a very high proliferation of MSCs and these cells satisfy the criteria defining stem cells (pluripotency-surface markers expression). The combination of BMP-2 + TGF-β 1 strongly induces the chondrogenic differentiation of MSCs and prevents HtrA1 expression. siRNAs targeting Col1a1 and Htra1 were functionally validated. Ultimately, the combined use of specific culture conditions defined here with specific growth factors and a Col1a1 siRNAs (50 nM) association leads to the in vitro synthesis of a hyaline-type neocartilage whose chondrocytes present an optimal phenotypic index similar to that of healthy, differentiated chondrocytes. Our results lead the way to setting up pre-clinical trials in horses to better understand the reaction of neocartilage substitute and to carry out a proof-of-concept of this therapeutic strategy on a large animal model.

  10. Time-sequential changes of differentially expressed miRNAs during the process of anterior lumbar interbody fusion using equine bone protein extract, rhBMP-2 and autograft

    Science.gov (United States)

    Chen, Da-Fu; Zhou, Zhi-Yu; Dai, Xue-Jun; Gao, Man-Man; Huang, Bao-Ding; Liang, Tang-Zhao; Shi, Rui; Zou, Li-Jin; Li, Hai-Sheng; Bünger, Cody; Tian, Wei; Zou, Xue-Nong

    2014-03-01

    The precise mechanism of bone regeneration in different bone graft substitutes has been well studied in recent researches. However, miRNAs regulation of the bone formation has been always mysterious. We developed the anterior lumbar interbody fusion (ALIF) model in pigs using equine bone protein extract (BPE), recombinant human bone morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS), and autograft as bone graft substitute, respectively. The miRNA and gene expression profiles of different bone graft materials were examined using microarray technology and data analysis, including self-organizing maps, KEGG pathway and Biological process GO analyses. We then jointly analyzed miRNA and mRNA profiles of the bone fusion tissue at different time points respectively. Results showed that miRNAs, including let-7, miR-129, miR-21, miR-133, miR-140, miR-146, miR-184, and miR-224, were involved in the regulation of the immune and inflammation response, which provided suitable inflammatory microenvironment for bone formation. At late stage, several miRNAs directly regulate SMAD4, Estrogen receptor 1 and 5-hydroxytryptamine (serotonin) receptor 2C for bone formation. It can be concluded that miRNAs play important roles in balancing the inflammation and bone formation.

  11. Detection of growth factor binding to gelatin and heparin using a photonic crystal optical biosensor

    International Nuclear Information System (INIS)

    Morgan, Abby W.; Chan, Leo L.; Sendemir-Urkmez, Aylin; Cunningham, Brian T.; Jamison, Russell D.

    2010-01-01

    Drug-carrier interactions are important to protein controlled release systems to protect the protein from denaturation and ensure properly timed release. A novel photonic crystal biosensor was used to investigate a gelatin-protein controlled release system to determine the amount of protein bound to the carrier at physiological conditions. The Biomolecular Interaction Detection (BIND) system reflects a narrow band of wavelengths when white light is shone incident to the grating. As mass is deposited onto the surface, the peak wavelength value is shifted due to changes in the optical density of the biosensor. The BIND system was used to detect the binding of growth factors onto acidic gelatin, basic gelatin, and heparin on the sensor surface. Through a series of experiments, including functionalizing the sensor, adjusting the ionic strength of the solution, adjusting the substrate concentration, and minimizing non-specific signal, the adsorption of the gelatins and heparin on the sensor was enhanced. The binding interaction of recombinant human transforming growth factor (rhTGF)-β1 and bone morphogenetic protein (rhBMP)-2 with the two types of gelatin and heparin were investigated. The strength of the interaction between rhTGF-β1 and the substrates is in the following order: heparin > acidic gelatin > basic gelatin. RhBMP-2 bound to the substrates but with less intensity than TGF-β1: heparin > basic gelatin > acidic gelatin. This work provides support for the controlled release mechanism through degradation of the gelatin carrier.

  12. Platelet-rich plasma stimulates osteoblastic differentiation in the presence of BMPs

    International Nuclear Information System (INIS)

    Tomoyasu, Akihiro; Higashio, Kanji; Kanomata, Kazuhiro; Goto, Masaaki; Kodaira, Kunihiko; Serizawa, Hiroko; Suda, Tatsuo; Nakamura, Atsushi; Nojima, Junya; Fukuda, Toru; Katagiri, Takenobu

    2007-01-01

    Platelet-rich plasma (PRP) is clinically used as an autologous blood product to stimulate bone formation in vivo. In the present study, we examined the effects of PRP on proliferation and osteoblast differentiation in vitro in the presence of bone morphogenetic proteins (BMPs). PRP and its soluble fraction stimulated osteoblastic differentiation of myoblasts and osteoblastic cells in the presence of BMP-2, BMP-4, BMP-6 or BMP-7. The soluble PRP fraction stimulated osteoblastic differentiation in 3D cultures using scaffolds made of collagen or hydroxyapatite. Moreover, heparin-binding fractions obtained from serum also stimulated osteoblastic differentiation in the presence of BMP-4. These results suggested that platelets contain not only growth factors for proliferation but also novel potentiator(s) for BMP-dependent osteoblastic differentiation

  13. Macrolactin F inhibits RANKL-mediated osteoclastogenesis by suppressing Akt, MAPK and NFATc1 pathways and promotes osteoblastogenesis through a BMP-2/smad/Akt/Runx2 signaling pathway.

    Science.gov (United States)

    Li, Liang; Sapkota, Mahesh; Gao, Ming; Choi, Hyukjae; Soh, Yunjo

    2017-11-15

    The balance between bone formation and bone resorption is maintained by osteoblasts and osteoclasts. In the current study, macrolactin F (MF) was investigated for novel biological activity on the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclastogenesis in primary bone marrow-derived macrophages (BMMs). We found that RANKL-induced osteoclast formation and differentiation from BMMs was significantly inhibited by MF in a dose-dependent manner without cytotoxicity. RANKL-induced F-actin ring formation and bone resorption activity in BMMs which was attenuated by MF. In addition, MF suppressed the expression of osteoclast-related genes, including c-myc, RANK, tartrate-resistant acid phosphatase (TRAP), nuclear factor of activated T cells c1 (NFATc1), cathepsin K and matrix metalloproteinase 9 (MMP9). Furthermore, the protein expression NFATc1, c-Fos, MMP9, cathepsin K and phosphorylation of Jun N-terminal kinase (JNK), p38 and Akt were also down-regulated by MF treatment. Interestingly, MF promoted pre-osteoblast cell differentiation on Alizarin Red-mineralization activity, alkaline phosphatase (ALP) activity, and the expression of osteoblastogenic markers including Runx2, Osterix, Smad4, ALP, type I collagen alpha 1 (Col1α), osteopontin (OPN), and osteocalcin (OCN) via activation of the BMP-2/smad/Akt/Runx2 pathway on MC3T3-E1. Taken together, these results indicate that MF may be useful as a therapeutic agent to enhance bone health and treat osteoporosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Mapping the heparin-binding site of the BMP antagonist gremlin by site-directed mutagenesis based on predictive modelling.

    Science.gov (United States)

    Tatsinkam, Arnold Junior; Mulloy, Barbara; Rider, Christopher C

    2015-08-15

    Gremlin is a member of the CAN (cerberus and DAN) family of secreted BMP (bone morphogenetic protein) antagonists and also an agonist of VEGF (vascular endothelial growth factor) receptor-2. It is critical in limb skeleton and kidney development and is re-expressed during tissue fibrosis. Gremlin binds strongly to heparin and heparan sulfate and, in the present study, we sought to investigate its heparin-binding site. In order to explore a putative non-contiguous binding site predicted by computational molecular modelling, we substituted a total of 11 key arginines and lysines located in three basic residue sequence clusters with homologous sequences from cerberus and DAN (differential screening selected gene abberative in neuroblastoma), CAN proteins which lack basic residues in these positions. A panel of six Myc-tagged gremlin mutants, MGR-1-MGR-6 (MGR, mutant gremlin), each containing different combinations of targeted substitutions, all showed markedly reduced affinity for heparin as demonstrated by their NaCl elution on heparin affinity chromatography, thus verifying our predictions. Both MGR-5 and MGR-6 retained BMP-4-binding activity comparable to that of wild-type gremlin. Low-molecular-mass heparin neither promoted nor inhibited BMP-4 binding. Finally, glutaraldehyde cross-linking demonstrated that gremlin forms non-covalent dimers, similar behaviour to that of DAN and also PRDC (protein related to cerberus and DAN), another CAN protein. The resulting dimer would possess two heparin-binding sites, each running along an exposed surface on the second β-strand finger loop of one of the monomers. © 2015 Authors; published by Portland Press Limited.

  15. Bone Morphogenetic Proteins 2/4 Are Upregulated during the Early Development of Vascular Calcification in Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Xiao Wei

    2018-01-01

    Full Text Available Vascular calcification is a main cause of increased cardiovascular morbidity and mortality in chronic kidney disease (CKD patients. This study aimed to investigate the role of the bone morphogenetic protein (BMP signaling pathway in the early development of vascular calcification in CKD. A CKD vascular calcification rat model was established by providing rats with a 1.8% high-phosphorus diet and an intragastric administration of 2.5% adenine suspension. The kidney and aortic pathologies were analyzed. Blood biochemical indicators, serum BMP-2 and BMP-4 levels, and aortic calcium content were determined. The expression levels of BMP-2, BMP-4, bone morphogenetic protein receptor-IA (BMPR-IA, and matrix Gla protein (MGP in aorta were examined by quantitative real-time polymerase chain reaction and immunohistochemistry. Compared with the normal control (Nor rats, the CKD rats exhibited a significantly decreased body weight and an increased kidney weight as well as abnormal renal function and calcium-phosphorus metabolism. Aortic von Kossa and Alizarin red staining showed massive granular deposition and formation of calcified nodules in aorta at 8 weeks. The aortic calcium content was significantly increased, which was positively correlated with the serum BMP-2 (r=0.929; P<0.01 and serum BMP-4 (r=0.702; P<0.01 levels in CKD rats. The rat aortic BMP-2 mRNA level in the CKD rats was persistently increased, and the BMP-4 mRNA level was prominently increased at the 4th week, declining thereafter. Strong staining of BMP-2, BMP-4, BMPR-IA, and MGP proteins was observed in the tunica media of the aorta from the 4th week after model induction. In conclusion, activation of the BMP signaling pathway is involved in the early development of vascular calcification in CKD. Therefore, elevated serum BMP-2 and BMP-4 levels may serve as serum markers for CKD vascular calcification.

  16. Insulin-like growth factor binding protein-3 affects osteogenic efficacy on dental implants in rat mandible

    Energy Technology Data Exchange (ETDEWEB)

    Bhattarai, Govinda; Lee, Young-Hee [Department of Oral Biochemistry, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of); Lee, Min-Ho [Department of Dental Materials, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of); Park, Il-Song [Division of Advanced Materials Engineering, Research Center for Advanced Materials, Development and Institute of Biodegradable Materials, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Yi, Ho-Keun, E-mail: yihokn@chonbuk.ac.kr [Department of Oral Biochemistry, Institute of Oral Bioscience, School of Dentistry, Chonbuk National University, Jeonju (Korea, Republic of)

    2015-10-01

    Insulin like growth factor binding protein-3 (IGFBP-3) in bone cells and its utilization in dental implants have not been well studied. The aim of this study was to determine the osteogenic efficacy of chitosan gold nanoparticles (Ch-GNPs) conjugated with IGFBP-3 coated titanium (Ti) implants. Ch-GNPs were conjugated with IGFBP-3 plasmid DNA through a coacervation process. Conjugation was cast over Ti surfaces, and cells were seeded on coated surfaces. For in vitro analysis the expression of different proteins was analyzed by immunoblotting. For in vivo analysis, Ch-GNP/IGFBP-3 coated implants were installed in rat mandibles. Four weeks post-implantation, mandibles were examined by microcomputed tomography (μCT), immunohistochemistry, hematoxylin & eosin and tartrate resistance acid phosphatase staining. In vitro overexpressed Ch-GNP/IGFBP-3 coated Ti surfaces was associated with activation of extracellular signal related kinase (ERK), inhibition of the stress activated protein c-Jun N-terminal kinase (JNK) and enhanced bone morphogenetic protein (BMP)-2 and 7 compared to control. Further, in vivo, Ch-GNP/IGFBP-3 coated implants were associated with inhibition of implant induced osteoclastogenesis molecules, receptor activator of nuclear factor kappa-B ligand (RANKL) and enhanced expression of osteogenic molecules including BMP2/7 and osteopontin (OPN). The μCT analysis demonstrated that IGFBP-3 increased the volume of newly formed bone surrounding the implants compared to control (n = 5; p < 0.05). These results support the view that IGFBP-3 overexpression diminishes osteoclastogenesis and enhances osteogenesis of Ti implants, and can serve as a potent molecule for the development of good implantation. - Highlights: • Chitosan gold nanoparticles were conjugated with IGFBP-3 and coated onto surface of the titanium implants for gene delivery to bone. • Implants were inserted in rat mandible for 4 weeks. • Parameters studied: histopathology and radiology.

  17. Insulin-like growth factor binding protein-3 affects osteogenic efficacy on dental implants in rat mandible

    International Nuclear Information System (INIS)

    Bhattarai, Govinda; Lee, Young-Hee; Lee, Min-Ho; Park, Il-Song; Yi, Ho-Keun

    2015-01-01

    Insulin like growth factor binding protein-3 (IGFBP-3) in bone cells and its utilization in dental implants have not been well studied. The aim of this study was to determine the osteogenic efficacy of chitosan gold nanoparticles (Ch-GNPs) conjugated with IGFBP-3 coated titanium (Ti) implants. Ch-GNPs were conjugated with IGFBP-3 plasmid DNA through a coacervation process. Conjugation was cast over Ti surfaces, and cells were seeded on coated surfaces. For in vitro analysis the expression of different proteins was analyzed by immunoblotting. For in vivo analysis, Ch-GNP/IGFBP-3 coated implants were installed in rat mandibles. Four weeks post-implantation, mandibles were examined by microcomputed tomography (μCT), immunohistochemistry, hematoxylin & eosin and tartrate resistance acid phosphatase staining. In vitro overexpressed Ch-GNP/IGFBP-3 coated Ti surfaces was associated with activation of extracellular signal related kinase (ERK), inhibition of the stress activated protein c-Jun N-terminal kinase (JNK) and enhanced bone morphogenetic protein (BMP)-2 and 7 compared to control. Further, in vivo, Ch-GNP/IGFBP-3 coated implants were associated with inhibition of implant induced osteoclastogenesis molecules, receptor activator of nuclear factor kappa-B ligand (RANKL) and enhanced expression of osteogenic molecules including BMP2/7 and osteopontin (OPN). The μCT analysis demonstrated that IGFBP-3 increased the volume of newly formed bone surrounding the implants compared to control (n = 5; p < 0.05). These results support the view that IGFBP-3 overexpression diminishes osteoclastogenesis and enhances osteogenesis of Ti implants, and can serve as a potent molecule for the development of good implantation. - Highlights: • Chitosan gold nanoparticles were conjugated with IGFBP-3 and coated onto surface of the titanium implants for gene delivery to bone. • Implants were inserted in rat mandible for 4 weeks. • Parameters studied: histopathology and radiology.

  18. CXXC5 is a novel BMP4-regulated modulator of Wnt signaling in neural stem cells

    Czech Academy of Sciences Publication Activity Database

    Andersson, T.; Södersten, E.; Duckworth, J.K.; Cascante, A.; Fritz, N.; Sacchetti, P.; Červenka, I.; Bryja, Vítězslav; Hermanson, O.

    2008-01-01

    Roč. 284, č. 6 (2008), s. 3672-3681 ISSN 0021-9258 Grant - others:GA AV ČR(CZ) KJB501630801 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : Wnt signaling * CXXC5 * neural stem cells Subject RIV: BO - Biophysics Impact factor: 5.520, year: 2008

  19. Total iron binding capacity

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003489.htm Total iron binding capacity To use the sharing features on this page, please enable JavaScript. Total iron binding capacity (TIBC) is a blood test to ...

  20. RNA Binding Proteins in Eye Development and Disease: Implication of Conserved RNA Granule Components

    Science.gov (United States)

    Dash, Soma; Siddam, Archana D.; Barnum, Carrie E.; Janga, Sarath Chandra

    2016-01-01

    The molecular biology of metazoan eye development is an area of intense investigation. These efforts have led to the surprising recognition that although insect and vertebrate eyes have dramatically different structures, the orthologs or family members of several conserved transcription and signaling regulators such as Pax6, Six3, Prox1 and Bmp4 are commonly required for their development. In contrast, our understanding of post-transcriptional regulation in eye development and disease, particularly regarding the function of RNA binding proteins (RBPs), is limited. We examine the present knowledge of RBPs in eye development in the insect model Drosophila, as well as several vertebrate models such as fish, frog, chicken and mouse. Interestingly, of the 42 RBPs that have been investigated with for their expression or function in vertebrate eye development, 24 (~60%) are recognized in eukaryotic cells as components of RNA granules such as Processing bodies (P-bodies), Stress granules, or other specialized ribonucleoprotein (RNP) complexes. We discuss the distinct developmental and cellular events that may necessitate potential RBP/RNA granule-associated RNA regulon models to facilitate post-transcriptional control of gene expression in eye morphogenesis. In support of these hypotheses, three RBPs and RNP/RNA granule components Tdrd7, Caprin2 and Stau2 are linked to ocular developmental defects such as congenital cataract, Peters anomaly and microphthalmia in human patients or animal models. We conclude by discussing the utility of interdisciplinary approaches such as the bioinformatics tool iSyTE (integrated Systems Tool for Eye gene discovery) to prioritize RBPs for deriving post-transcriptional regulatory networks in eye development and disease. PMID:27133484

  1. Structurally characterized 1,1,3,3-tetramethylguanidine solvated magnesium aryloxide complexes: [Mg(mu-OEt)(DBP)(H-TMG)]2, [Mg(mu-OBc)(DBP)(H-TMG)]2, [Mg(mu-TMBA)(DBP)(H-TMG)]2, [Mg(mu-DPP)(DBP)(H-TMG)]2, [Mg(BMP)2(H-TMG)2], [Mg(O-2,6-Ph2C6H3)2 (H-TMG)2].

    Science.gov (United States)

    Monegan, Jessie D; Bunge, Scott D

    2009-04-06

    The synthesis and structural characterization of several 1,1,3,3-tetramethylguanidine (H-TMG) solvated magnesium aryloxide complexes are reported. Bu(2)Mg was successfully reacted with H-TMG, HOC(6)H(3)(CMe(3))(2)-2,6 (H-DBP), and either ethanol, a carboxylic acid, or diphenyl phosphate in a 1:1 ratio to yield the corresponding [Mg(mu-L)(DBP)(H-TMG)](2) where L = OCH(2)CH(3) (OEt, 1), O(2)CC(CH(3))(3) (OBc, 2), O(2)C(C(6)H(2)-2,4,6-(CH(3))(3)) (TMBA, 3), or O(2)P(OC(6)H(5))(2) (DPP, 4). Bu(2)Mg was also reacted with two equivalents of H-TMG and HOC(6)H(3)(CMe(3))-2-(CH(3))-6 (BMP) or HO-2,6-Ph(2)C(6)H(3) to yield [Mg(BMP)(2)(H-TMG)(2)] (5) and [Mg(O-2,6-Ph(2)C(6)H(3))(2)(H-TMG)(2)] (6). Compounds 1-6 were characterized by single-crystal X-ray diffraction. Polymerization of l- and rac-lactide with 1 was found to generate polylactide (PLA). A discussion concerning the relevance of compounds 2 - 4 to the structure of Mg-activated phosphatase enzymes is also provided. The bulk powders for all complexes were found to be in agreement with the crystal structures based on elemental analyses, FT-IR spectroscopy, and (1)H, (13)C and (31)P NMR studies.

  2. Feature Binding in Zebrafish

    Directory of Open Access Journals (Sweden)

    P Neri

    2012-07-01

    Full Text Available Binding operations are primarily ascribed to cortex or similarly complex avian structures. My experiments show that the zebrafish, a lower vertebrate lacking cortex, supports visual feature binding of form and motion for the purpose of social behavior. These results challenge the notion that feature binding may require highly evolved neural structures and demonstrate that the nervous system of lower vertebrates can afford unexpectedly complex computations.

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

    Science.gov (United States)

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

    2000-12-01

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

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

    Science.gov (United States)

    2008-03-01

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

  5. Addition of bone morphogenetic protein type 2 to ascorbate and β-glycerophosphate supplementation did not enhance osteogenic differentiation of human adipose-derived stem cells

    Directory of Open Access Journals (Sweden)

    Ariadne Cristiane Cabral Cruz

    2012-12-01

    Full Text Available Bone morphogenetic protein type 2 (BMP-2 is a potent local factor, which promotes bone formation and has been used as an osteogenic supplement for mesenchymal stem cells. OBJECTIVES: This study evaluated the effect of a recombinant BMP-2 as well as the endogenous BMP-4 and BMP-7 in the osteogenic differentiation of adipose-derived stem cells (ASCs in medium supplemented with ascorbate and β-glycerophosphate. MATERIAL AND METHODS: Human ASCs were treated with osteogenic medium in the presence (ASCs+OM+BMP-2 or absence (ASCs+OM of BMP-2. The alkaline phosphatase (ALP activity was determined and the extracellular matrix mineralization was evaluated by Von Kossa staining and calcium quantification. The expressions of BMP-4, BMP-7, Smad1, Smad4, and phosphorylated Smad1/5/8 were analyzed by western blotting. Relative mRNA expressions of Smad1, BMP receptor type II (BMPR-II, osteonectin, and osteocalcin were evaluated by qPCR. Results: ASCs+OM demonstrated the highest expression of BMP-4 and BMP-7 at days 21 and 7, respectively, the highest levels of BMPR-II mRNA expression at day 28, and the highest levels of Smad1 mRNA at days 14 and 28. ASCs+OM+BMP-2 demonstrated the highest levels of Smad1 mRNA expression at days 1, 7, and 21, the highest expression of Smad1 at day 7, the highest expression of Smad4 at day 14, the highest ALP activity at days 14 and 21, and expression of phosphorylated Smad1/5/8 at day 7. ASCs+OM and ASCs+OM+BMP2 showed similar ALP activity at days 7 and 28, similar osteonectin and osteocalcin mRNA expression at all time periods, and similar calcium depositions at all time periods. CONCLUSIONS: We concluded that human ASCs expressed endogenous BMP-4 and BMP-7. Moreover, the supplementation of ASCs with BMP-2 did not increase the level of osteogenic markers in the initial (ALP activity, intermediate (osteonectin and osteocalcin, or final (calcium deposition phases, suggesting that the exogenous addition of BMP-2 did not improve

  6. Melanin-binding radiopharmaceuticals

    International Nuclear Information System (INIS)

    Packer, S.; Fairchild, R.G.; Watts, K.P.; Greenberg, D.; Hannon, S.J.

    1980-01-01

    The scope of this paper is limited to an analysis of the factors that are important to the relationship of radiopharmaceuticals to melanin. While the authors do not attempt to deal with differences between melanin-binding vs. melanoma-binding, a notable variance is assumed

  7. Competitive protein binding assay

    International Nuclear Information System (INIS)

    Kaneko, Toshio; Oka, Hiroshi

    1975-01-01

    The measurement of cyclic GMP (cGMP) by competitive protein binding assay was described and discussed. The principle of binding assay was represented briefly. Procedures of our method by binding protein consisted of preparation of cGMP binding protein, selection of 3 H-cyclic GMP on market, and measurement procedures. In our method, binding protein was isolated from the chrysalis of silk worm. This method was discussed from the points of incubation medium, specificity of binding protein, the separation of bound cGMP from free cGMP, and treatment of tissue from which cGMP was extracted. cGMP existing in the tissue was only one tenth or one scores of cGMP, and in addition, cGMP competed with cGMP in binding with binding protein. Therefore, Murad's technique was applied to the isolation of cGMP. This method provided the measurement with sufficient accuracy; the contamination by cAMP was within several per cent. (Kanao, N.)

  8. Gremlin-1 induces BMP-independent tumor cell proliferation, migration, and invasion.

    Directory of Open Access Journals (Sweden)

    Minsoo Kim

    Full Text Available Gremlin-1, a bone morphogenetic protein (BMP antagonist, is overexpressed in various cancerous tissues but its role in carcinogenesis has not been established. Here, we report that gremlin-1 binds various cancer cell lines and this interaction is inhibited by our newly developed gremlin-1 antibody, GRE1. Gremlin-1 binding to cancer cells was unaffected by the presence of BMP-2, BMP-4, and BMP-7. In addition, the binding was independent of vascular endothelial growth factor receptor-2 (VEGFR2 expression on the cell surface. Addition of gremlin-1 to A549 cells induced a fibroblast-like morphology and decreased E-cadherin expression. In a scratch wound healing assay, A549 cells incubated with gremlin-1 or transfected with gremlin-1 showed increased migration, which was inhibited in the presence of the GRE1 antibody. Gremlin-1 transfected A549 cells also exhibited increased invasiveness as well as an increased growth rate. These effects were also inhibited by the addition of the GRE1 antibody. In conclusion, this study demonstrates that gremlin-1 directly interacts with cancer cells in a BMP- and VEGFR2-independent manner and can induce cell migration, invasion, and proliferation.

  9. SHBG (Sex Hormone Binding Globulin)

    Science.gov (United States)

    ... Links Patient Resources For Health Professionals Subscribe Search Sex Hormone Binding Globulin (SHBG) Send Us Your Feedback ... As Testosterone-estrogen Binding Globulin TeBG Formal Name Sex Hormone Binding Globulin This article was last reviewed ...

  10. CARBOHYDRATE-CONTAINING COMPOUNDS WHICH BIND TO CARBOHYDRATE BINDING RECEPTORS

    DEFF Research Database (Denmark)

    1995-01-01

    Carbohydrate-containing compounds which contain saccharides or derivatives thereof and which bind to carbohydrate binding receptors are useful in pharmaceutical products for treatment of inflammatory diseases and other diseases.......Carbohydrate-containing compounds which contain saccharides or derivatives thereof and which bind to carbohydrate binding receptors are useful in pharmaceutical products for treatment of inflammatory diseases and other diseases....

  11. A novel osteogenic oxysterol compound for therapeutic development to promote bone growth: activation of hedgehog signaling and osteogenesis through smoothened binding.

    Science.gov (United States)

    Montgomery, Scott R; Nargizyan, Taya; Meliton, Vicente; Nachtergaele, Sigrid; Rohatgi, Rajat; Stappenbeck, Frank; Jung, Michael E; Johnson, Jared S; Aghdasi, Bayan; Tian, Haijun; Weintraub, Gil; Inoue, Hirokazu; Atti, Elisa; Tetradis, Sotirios; Pereira, Renata C; Hokugo, Akishige; Alobaidaan, Raed; Tan, Yanlin; Hahn, Theodor J; Wang, Jeffrey C; Parhami, Farhad

    2014-08-01

    Osteogenic factors are often used in orthopedics to promote bone growth, improve fracture healing, and induce spine fusion. Osteogenic oxysterols are naturally occurring molecules that were shown to induce osteogenic differentiation in vitro and promote spine fusion in vivo. The purpose of this study was to identify an osteogenic oxysterol more suitable for clinical development than those previously reported, and evaluate its ability to promote osteogenesis in vitro and spine fusion in rats in vivo. Among more than 100 oxysterol analogues synthesized, Oxy133 induced significant expression of osteogenic markers Runx2, osterix (OSX), alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteocalcin (OCN) in C3H10T1/2 mouse embryonic fibroblasts and in M2-10B4 mouse marrow stromal cells. Oxy133-induced activation of an 8X-Gli luciferase reporter, its direct binding to Smoothened, and the inhibition of Oxy133-induced osteogenic effects by the Hedgehog (Hh) pathway inhibitor, cyclopamine, demonstrated the role of Hh pathway in mediating osteogenic responses to Oxy133. Oxy133 did not stimulate osteogenesis via BMP or Wnt signaling. Oxy133 induced the expression of OSX, BSP, and OCN, and stimulated robust mineralization in primary human mesenchymal stem cells. In vivo, bilateral spine fusion occurred through endochondral ossification and was observed in animals treated with Oxy133 at the fusion site on X-ray after 4 weeks and confirmed with manual assessment, micro-CT (µCT), and histology after 8 weeks, with equal efficiency to recombinant human bone morphogenetic protein-2 (rhBMP-2). Unlike rhBMP-2, Oxy133 did not induce adipogenesis in the fusion mass and resulted in denser bone evidenced by greater bone volume/tissue volume (BV/TV) ratio and smaller trabecular separation. Findings here suggest that Oxy133 has significant potential as an osteogenic molecule with greater ease of synthesis and improved time to fusion compared to previously studied oxysterols. Small

  12. Hydrolysis and Sulfation Pattern Effects on Release of Bioactive Bone Morphogenetic Protein-2 from Heparin-Based Microparticles.

    Science.gov (United States)

    Tellier, Liane E; Miller, Tobias; McDevitt, Todd C; Temenoff, Johnna S

    2015-10-28

    Glycosaminoglycans (GAGs) such as heparin are promising materials for growth factor delivery due to their ability to efficiently bind positively charged growth factors including bone morphogenetic protein-2 (BMP-2) through their negatively charged sulfate groups. Therefore, the goal of this study was to examine BMP-2 release from heparin-based microparticles (MPs) after first, incorporating a hydrolytically degradable crosslinker and varying heparin content within MPs to alter MP degradation and second, altering the sulfation pattern of heparin within MPs to vary BMP-2 binding and release. Using varied MP formulations, it was found that the time course of MP degradation for 1 wt% heparin MPs was ~4 days slower than 10 wt% heparin MPs, indicating that MP degradation was dependent on heparin content. After incubating 100 ng BMP-2 with 0.1 mg MPs, most MP formulations loaded BMP-2 with ~50% efficiency and significantly more BMP-2 release (60% of loaded BMP-2) was observed from more sulfated heparin MPs (MPs with ~100% and 80% of native sulfation). Similarly, BMP-2 bioactivity in more sulfated heparin MP groups was at least four-fold higher than soluble BMP-2 and less sulfated heparin MP groups, as determined by an established C2C12 cell alkaline phosphatase (ALP) assay. Ultimately, the two most sulfated 10 wt% heparin MP formulations were able to efficiently load and release BMP-2 while enhancing BMP-2 bioactivity, making them promising candidates for future growth factor delivery applications.

  13. Sequential memory: Binding dynamics

    Science.gov (United States)

    Afraimovich, Valentin; Gong, Xue; Rabinovich, Mikhail

    2015-10-01

    Temporal order memories are critical for everyday animal and human functioning. Experiments and our own experience show that the binding or association of various features of an event together and the maintaining of multimodality events in sequential order are the key components of any sequential memories—episodic, semantic, working, etc. We study a robustness of binding sequential dynamics based on our previously introduced model in the form of generalized Lotka-Volterra equations. In the phase space of the model, there exists a multi-dimensional binding heteroclinic network consisting of saddle equilibrium points and heteroclinic trajectories joining them. We prove here the robustness of the binding sequential dynamics, i.e., the feasibility phenomenon for coupled heteroclinic networks: for each collection of successive heteroclinic trajectories inside the unified networks, there is an open set of initial points such that the trajectory going through each of them follows the prescribed collection staying in a small neighborhood of it. We show also that the symbolic complexity function of the system restricted to this neighborhood is a polynomial of degree L - 1, where L is the number of modalities.

  14. Cellulose binding domain proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc; Doi, Roy

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  15. Binding and Bulgarian

    NARCIS (Netherlands)

    Schürcks-Grozeva, Lilia Lubomirova

    2003-01-01

    In haar proefschrift analyseert Lilia Schürcks de anaforische verschijnselen in de Bulgaarse taal. Het gaat dan om wederkerende aspecten, uitgedrukt bij woorden als ‘zich’ en ‘elkaar’. De situatie in het Bulgaars blijkt moeilijk in te passen in de klassieke Binding Theory van Noam Chomsky. Bron: RUG

  16. Nanostructured hydroxyapatite surfaces-mediated adsorption alters recognition of BMP receptor IA and bioactivity of bone morphogenetic protein-2.

    Science.gov (United States)

    Huang, Baolin; Yuan, Yuan; Ding, Sai; Li, Jianbo; Ren, Jie; Feng, Bo; Li, Tong; Gu, Yuantong; Liu, Changsheng

    2015-11-01

    Highly efficient loading of bone morphogenetic protein-2 (BMP-2) onto carriers with desirable performance is still a major challenge in the field of bone regeneration. Till now, the nanoscaled surface-induced changes of the structure and bioactivity of BMP-2 remains poorly understood. Here, the effect of nanoscaled surface on the adsorption and bioactivity of BMP-2 was investigated with a series of hydroxyapatite surfaces (HAPs): HAP crystal-coated surface (HAP), HAP crystal-coated polished surface (HAP-Pol), and sintered HAP crystal-coated surface (HAP-Sin). The adsorption dynamics of recombinant human BMP-2 (rhBMP-2) and the accessibility of the binding epitopes of adsorbed rhBMP-2 for BMP receptors (BMPRs) were examined by a quartz crystal microbalance with dissipation. Moreover, the bioactivity of adsorbed rhBMP-2 and the BMP-induced Smad signaling were investigated with C2C12 model cells. A noticeably high mass-uptake of rhBMP-2 and enhanced recognition of BMPR-IA to adsorbed rhBMP-2 were found on the HAP-Pol surface. For the rhBMP-2-adsorbed HAPs, both ALP activity and Smad signaling increased in the order of HAP-Sinuses of rhBMP-2 in clinical applications and arouse broad interests among researchers in the fields of nano-biotechnology, biomaterials and bone tissue engineering. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  17. Bone morphogenetic protein-induced MSX1 and MSX2 inhibit myocardin-dependent smooth muscle gene transcription.

    Science.gov (United States)

    Hayashi, Ken'ichiro; Nakamura, Seiji; Nishida, Wataru; Sobue, Kenji

    2006-12-01

    During the onset and progression of atherosclerosis, the vascular smooth muscle cell (VSMC) phenotype changes from differentiated to dedifferentiated, and in some cases, this change is accompanied by osteogenic transition, resulting in vascular calcification. One characteristic of dedifferentiated VSMCs is the down-regulation of smooth muscle cell (SMC) marker gene expression. Bone morphogenetic proteins (BMPs), which are involved in the induction of osteogenic gene expression, are detected in calcified vasculature. In this study, we found that the BMP2-, BMP4-, and BMP6-induced expression of Msx transcription factors (Msx1 and Msx2) preceded the down-regulation of SMC marker expression in cultured differentiated VSMCs. Either Msx1 or Msx2 markedly reduced the myocardin-dependent promoter activities of SMC marker genes (SM22alpha and caldesmon). We further investigated interactions between Msx1 and myocardin/serum response factor (SRF)/CArG-box motif (cis element for SRF) using coimmunoprecipitation, gel-shift, and chromatin immunoprecipitation assays. Our results showed that Msx1 or Msx2 formed a ternary complex with SRF and myocardin and inhibited the binding of SRF or SRF/myocardin to the CArG-box motif, resulting in inhibition of their transcription.

  18. Bone Morphogenetic Protein-Induced Msx1 and Msx2 Inhibit Myocardin-Dependent Smooth Muscle Gene Transcription▿

    Science.gov (United States)

    Hayashi, Ken'ichiro; Nakamura, Seiji; Nishida, Wataru; Sobue, Kenji

    2006-01-01

    During the onset and progression of atherosclerosis, the vascular smooth muscle cell (VSMC) phenotype changes from differentiated to dedifferentiated, and in some cases, this change is accompanied by osteogenic transition, resulting in vascular calcification. One characteristic of dedifferentiated VSMCs is the down-regulation of smooth muscle cell (SMC) marker gene expression. Bone morphogenetic proteins (BMPs), which are involved in the induction of osteogenic gene expression, are detected in calcified vasculature. In this study, we found that the BMP2-, BMP4-, and BMP6-induced expression of Msx transcription factors (Msx1 and Msx2) preceded the down-regulation of SMC marker expression in cultured differentiated VSMCs. Either Msx1 or Msx2 markedly reduced the myocardin-dependent promoter activities of SMC marker genes (SM22α and caldesmon). We further investigated interactions between Msx1 and myocardin/serum response factor (SRF)/CArG-box motif (cis element for SRF) using coimmunoprecipitation, gel-shift, and chromatin immunoprecipitation assays. Our results showed that Msx1 or Msx2 formed a ternary complex with SRF and myocardin and inhibited the binding of SRF or SRF/myocardin to the CArG-box motif, resulting in inhibition of their transcription. PMID:17030628

  19. Carboplatin binding to histidine

    Energy Technology Data Exchange (ETDEWEB)

    Tanley, Simon W. M. [University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom); Diederichs, Kay [University of Konstanz, D-78457 Konstanz (Germany); Kroon-Batenburg, Loes M. J. [Utrecht University, Padualaan 8, 3584 CH Utrecht (Netherlands); Levy, Colin [University of Manchester, 131 Princess Street, Manchester M1 7DN (United Kingdom); Schreurs, Antoine M. M. [Utrecht University, Padualaan 8, 3584 CH Utrecht (Netherlands); Helliwell, John R., E-mail: john.helliwell@manchester.ac.uk [University of Manchester, Brunswick Street, Manchester M13 9PL (United Kingdom)

    2014-08-29

    An X-ray crystal structure showing the binding of purely carboplatin to histidine in a model protein has finally been obtained. This required extensive crystallization trials and various novel crystal structure analyses. Carboplatin is a second-generation platinum anticancer agent used for the treatment of a variety of cancers. Previous X-ray crystallographic studies of carboplatin binding to histidine (in hen egg-white lysozyme; HEWL) showed the partial conversion of carboplatin to cisplatin owing to the high NaCl concentration used in the crystallization conditions. HEWL co-crystallizations with carboplatin in NaBr conditions have now been carried out to confirm whether carboplatin converts to the bromine form and whether this takes place in a similar way to the partial conversion of carboplatin to cisplatin observed previously in NaCl conditions. Here, it is reported that a partial chemical transformation takes place but to a transplatin form. Thus, to attempt to resolve purely carboplatin binding at histidine, this study utilized co-crystallization of HEWL with carboplatin without NaCl to eliminate the partial chemical conversion of carboplatin. Tetragonal HEWL crystals co-crystallized with carboplatin were successfully obtained in four different conditions, each at a different pH value. The structural results obtained show carboplatin bound to either one or both of the N atoms of His15 of HEWL, and this particular variation was dependent on the concentration of anions in the crystallization mixture and the elapsed time, as well as the pH used. The structural details of the bound carboplatin molecule also differed between them. Overall, the most detailed crystal structure showed the majority of the carboplatin atoms bound to the platinum centre; however, the four-carbon ring structure of the cyclobutanedicarboxylate moiety (CBDC) remained elusive. The potential impact of the results for the administration of carboplatin as an anticancer agent are described.

  20. Optical Binding of Nanowires

    Czech Academy of Sciences Publication Activity Database

    Simpson, Stephen Hugh; Zemánek, Pavel; Marago, O.M.; Jones, P.H.; Hanna, S.

    2017-01-01

    Roč. 17, č. 6 (2017), s. 3485-3492 ISSN 1530-6984 R&D Projects: GA ČR GB14-36681G Grant - others:AV ČR(CZ) CNR-16-12 Program:Bilaterální spolupráce Institutional support: RVO:68081731 Keywords : optical binding nanowires * Brownian motion * self-organization * non-equilibrium thermodynamics * non-equilibrium steady state * spin-orbit coupling * emergent phenomena Subject RIV: BH - Optics, Masers, Lasers OBOR OECD: Optics (including laser optics and quantum optics) Impact factor: 12.712, year: 2016

  1. IGF binding proteins.

    Science.gov (United States)

    Bach, Leon A

    2017-12-18

    Insulin-like growth factor binding proteins (IGFBPs) 1-6 bind IGFs but not insulin with high affinity. They were initially identified as serum carriers and passive inhibitors of IGF actions. However, subsequent studies showed that, although IGFBPs inhibit IGF actions in many circumstances, they may also potentiate these actions. IGFBPs are widely expressed in most tissues, and they are flexible endocrine and autocrine/paracrine regulators of IGF activity, which is essential for this important physiological system. More recently, individual IGFBPs have been shown to have IGF-independent actions. Mechanisms underlying these actions include (i) interaction with non-IGF proteins in compartments including the extracellular space and matrix, the cell surface and intracellularly; (ii) interaction with and modulation of other growth factor pathways including EGF, TGF- and VEGF; and (iii) direct or indirect transcriptional effects following nuclear entry of IGFBPs. Through these IGF-dependent and IGF-independent actions, IGFBPs modulate essential cellular processes including proliferation, survival, migration, senescence, autophagy and angiogenesis. They have been implicated in a range of disorders including malignant, metabolic, neurological and immune diseases. A more complete understanding of their cellular roles may lead to the development of novel IGFBP-based therapeutic opportunities.

  2. A BMP responsive transcriptional region in the chicken type X collagen gene.

    Science.gov (United States)

    Volk, S W; Luvalle, P; Leask, T; Leboy, P S

    1998-10-01

    Bone morphogenetic proteins (BMPs) were originally identified by their ability to induce ectopic bone formation and have been shown to promote both chondrogenesis and chondrocyte hypertrophy. BMPs have recently been found to activate a membrane serine/threonine kinase signaling mechanism in a variety of cell types, but the downstream effectors of BMP signaling in chondrocyte differentiation remain unidentified. We have previously reported that BMP-2 markedly stimulates type X collagen expression in prehypertrophic chick sternal chondrocytes, and that type X collagen mRNA levels in chondrocytes cultured under serum-free (SF) conditions are elevated 3- to 5-fold within 24 h. To better define the molecular mechanisms of induction of chondrocyte hypertrophy by BMPs, we examined the effect of BMPs on type X collagen production by 15-day chick embryo sternal chondrocytes cultured under SF conditions in the presence or absence of 30 ng/ml BMP-2, BMP-4, or BMP-7. Two populations of chondrocytes were used: one representing resting cartilage isolated from the caudal third of the sterna and the second representing prehypertrophic cartilage from the cephalic third of the sterna. BMP-2, BMP-4, and BMP-7 all effectively promoted chondrocyte maturation of cephalic sternal chondrocytes as measured by high levels of alkaline phosphatase, diminished levels of type II collagen, and induction of the hypertrophic chondrocyte-specific marker, type X collagen. To test whether BMP control of type X collagen expression occurs at the transcriptional level, we utilized plasmid constructs containing the chicken collagen X promoter and 5' flanking regions fused to a reporter gene. Constructs were transiently transfected into sternal chondrocytes cultured under SF conditions in the presence or absence of 30 ng/ml BMP-2, BMP-4, or BMP-7. A 533 bp region located 2.4-2.9 kb upstream from the type X collagen transcriptional start site was both necessary and sufficient for strong BMP responsiveness

  3. Pictorial binding: endeavor to classify

    Directory of Open Access Journals (Sweden)

    Zinchenko S.

    2015-01-01

    Full Text Available The article is devoted to the classification of bindings of the 1-19th centuries with a unique and untypical book binding decoration technique (encaustic, tempera and oil paintings. Analysis of design features, materials and techniques of art decoration made it possible to identify them as a separate type - pictorial bindings and divide them into four groups. The first group consists of Coptic bindings, decorated with icon-painting images in encaustic technique. The second group is made up of leather Western bindings of the 13-14th centuries, which have the decoration and technique of ornamentation close to iconography. The third group involves parchment bindings, ornamentation technique of which is closer to the miniature. The last group comprises bindings of East Slavic origin of the 15-19th centuries, decorated with icon-painting pictures made in the technique of tempera or oil painting. The proposed classification requires further basic research as several specific kinds of bindings have not yet been investigated

  4. Megalin binds and mediates cellular internalization of folate binding protein

    DEFF Research Database (Denmark)

    Birn, Henrik; Zhai, Xiaoyue; Holm, Jan

    2005-01-01

    Folate is an essential vitamin involved in a number of biological processes. High affinity folate binding proteins (FBPs) exist both as glycosylphosphatidylinositol-linked, membrane associated folate binding proteins and as soluble FBPs in plasma and some secretory fluids such as milk, saliva...... to express high levels of megalin, is inhibitable by excess unlabeled FBP and by receptor associated protein, a known inhibitor of binding to megalin. Immortalized rat yolk sac cells, representing an established model for studying megalin-mediated uptake, reveal (125)I-labeled FBP uptake which is inhibited...

  5. [3]tetrahydrotrazodone binding. Association with serotonin binding sites

    International Nuclear Information System (INIS)

    Kendall, D.A.; Taylor, D.P.; Enna, S.J.

    1983-01-01

    High (17 nM) and low (603 nM) affinity binding sites for [ 3 ]tetrahydrotrazodone ([ 3 ] THT), a biologically active analogue of trazodone, have been identified in rat brain membranes. The substrate specificity, concentration, and subcellular and regional distributions of these sites suggest that they may represent a component of the serotonin transmitter system. Pharmacological analysis of [ 3 ]THT binding, coupled with brain lesion and drug treatment experiments, revealed that, unlike other antidepressants, [ 3 ] THT does not attach to either a biogenic amine transporter or serotonin binding sites. Rather, it would appear that [ 3 ]THT may be an antagonist ligand for the serotonin binding site. This probe may prove of value in defining the mechanism of action of trazodone and in further characterizing serotonin receptors

  6. Nuclear variants of bone morphogenetic proteins

    Directory of Open Access Journals (Sweden)

    Meinhart Christopher A

    2010-03-01

    Full Text Available Abstract Background Bone morphogenetic proteins (BMPs contribute to many different aspects of development including mesoderm formation, heart development, neurogenesis, skeletal development, and axis formation. They have previously been recognized only as secreted growth factors, but the present study detected Bmp2, Bmp4, and Gdf5/CDMP1 in the nuclei of cultured cells using immunocytochemistry and immunoblotting of nuclear extracts. Results In all three proteins, a bipartite nuclear localization signal (NLS was found to overlap the site at which the proproteins are cleaved to release the mature growth factors from the propeptides. Mutational analyses indicated that the nuclear variants of these three proteins are produced by initiating translation from downstream alternative start codons. The resulting proteins lack N-terminal signal peptides and are therefore translated in the cytoplasm rather than the endoplasmic reticulum, thus avoiding proteolytic processing in the secretory pathway. Instead, the uncleaved proteins (designated nBmp2, nBmp4, and nGdf5 containing the intact NLSs are translocated to the nucleus. Immunostaining of endogenous nBmp2 in cultured cells demonstrated that the amount of nBmp2 as well as its nuclear/cytoplasmic distribution differs between cells that are in M-phase versus other phases of the cell cycle. Conclusions The observation that nBmp2 localization varies throughout the cell cycle, as well as the conservation of a nuclear localization mechanism among three different BMP family members, suggests that these novel nuclear variants of BMP family proteins play an important functional role in the cell.

  7. Protein binding of psychotropic agents

    International Nuclear Information System (INIS)

    Hassan, H.A.

    1990-01-01

    Based upon fluorescence measurements, protein binding of some psychotropic agents (chlorpromazine, promethazine, and trifluoperazine) to human IgG and HSA was studied in aqueous cacodylate buffer, PH7. The interaction parameters determined from emission quenching of the proteins. The interaction parameters determined include the equilibrium constant (K), calculated from equations derived by Borazan and coworkers, the number of binding sites (n) available to the monomer molecules on a single protein molecule. The results revealed a high level of affinity, as reflected by high values of K, and the existence of specific binding sites, since a limited number of n values are obtained. 39 tabs.; 37 figs.; 83 refs

  8. Superresolution microscopy with transient binding.

    Science.gov (United States)

    Molle, Julia; Raab, Mario; Holzmeister, Susanne; Schmitt-Monreal, Daniel; Grohmann, Dina; He, Zhike; Tinnefeld, Philip

    2016-06-01

    For single-molecule localization based superresolution, the concentration of fluorescent labels has to be thinned out. This is commonly achieved by photophysically or photochemically deactivating subsets of molecules. Alternatively, apparent switching of molecules can be achieved by transient binding of fluorescent labels. Here, a diffusing dye yields bright fluorescent spots when binding to the structure of interest. As the binding interaction is weak, the labeling is reversible and the dye ligand construct diffuses back into solution. This approach of achieving superresolution by transient binding (STB) is reviewed in this manuscript. Different realizations of STB are discussed and compared to other localization-based superresolution modalities. We propose the development of labeling strategies that will make STB a highly versatile tool for superresolution microscopy at highest resolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. To bind or not to bind? Different temporal binding effects from voluntary pressing and releasing actions.

    Science.gov (United States)

    Zhao, Ke; Chen, Yu-Hsin; Yan, Wen-Jing; Fu, Xiaolan

    2013-01-01

    Binding effect refers to the perceptual attraction between an action and an outcome leading to a subjective compression of time. Most studies investigating binding effects exclusively employ the "pressing" action without exploring other types of actions. The present study addresses this issue by introducing another action, releasing action or the voluntary lifting of the finger/wrist, to investigate the differences between voluntary pressing and releasing actions. Results reveal that releasing actions led to robust yet short-lived temporal binding effects, whereas pressing condition had steady temporal binding effects up to super-seconds. The two actions also differ in sensitivity to changes in temporal contiguity and contingency, which could be attributed to the difference in awareness of action. Extending upon current models of "willed action," our results provide insights from a temporal point of view and support the concept of a dual system consisting of predictive motor control and top-down mechanisms.

  10. Binding energies of cluster ions

    International Nuclear Information System (INIS)

    Parajuli, R.; Matt, S.; Scheier, P.; Echt, O.; Stamatovic, A.; Maerk, T.D.

    2002-01-01

    The binding energy of charged clusters may be measured by analyzing the kinetic energy released in the metastable decay of mass selected parent ions. Using finite heat bath theory to determine the binding energies of argon, neon, krypton, oxygen and nitrogen from their respective average kinetic energy released were carried out. A high-resolution double focussing two-sector mass spectrometer of reversed Nier-Johnson type geometry was used. MIKE ( mass-analysed ion kinetic energy) were measured to investigate decay reactions of mass-selected ions. For the inert gases neon (Ne n + ), argon (Ar n + ) and krypton (Kr n + ), it is found that the binding energies initially decrease with increasing size n and then level off at a value above the enthalpy of vaporization of the condensed phase. Oxygen cluster ions shown a characteristic dependence on cluster size (U-shape) indicating a change in the metastable fragmentation mechanism when going from the dimer to the decamer ion. (nevyjel)

  11. Metal binding by food components

    DEFF Research Database (Denmark)

    Tang, Ning

    for zinc binding by the investigated amino acids, peptides and proteins. The thiol group or imidazole group containing amino acids, peptides and proteins which exhibited strong zinc binding ability were further selected for interacting with zinc salts in relation to zinc absorption. The interactions...... between the above selected food components and zinc citrate or zinc phytate will lead to the enhanced solubility of zinc citrate or zinc phytate. The main driving force for this observed solubility enhancement is the complex formation between zinc and investigated food components as revealed by isothermal...... titration calorimetry and quantum mechanical calculations. This is due to the zinc binding affinity of the relatively softer ligands (investigated food components) will become much stronger than citrate or phytate when they present together in aqueous solution. This mechanism indicates these food components...

  12. Skyrmions with low binding energies

    Energy Technology Data Exchange (ETDEWEB)

    Gillard, Mike, E-mail: m.n.gillard@leeds.ac.uk; Harland, Derek, E-mail: d.g.harland@leeds.ac.uk; Speight, Martin, E-mail: speight@maths.leeds.ac.uk

    2015-06-15

    Nuclear binding energies are investigated in two variants of the Skyrme model: the first replaces the usual Skyrme term with a term that is sixth order in derivatives, and the second includes a potential that is quartic in the pion fields. Solitons in the first model are shown to deviate significantly from ansätze previously assumed in the literature. The binding energies obtained in both models are lower than those obtained from the standard Skyrme model, and those obtained in the second model are close to the experimental values.

  13. Skyrmions with low binding energies

    International Nuclear Information System (INIS)

    Gillard, Mike; Harland, Derek; Speight, Martin

    2015-01-01

    Nuclear binding energies are investigated in two variants of the Skyrme model: the first replaces the usual Skyrme term with a term that is sixth order in derivatives, and the second includes a potential that is quartic in the pion fields. Solitons in the first model are shown to deviate significantly from ansätze previously assumed in the literature. The binding energies obtained in both models are lower than those obtained from the standard Skyrme model, and those obtained in the second model are close to the experimental values

  14. Skyrmions with low binding energies

    Directory of Open Access Journals (Sweden)

    Mike Gillard

    2015-06-01

    Full Text Available Nuclear binding energies are investigated in two variants of the Skyrme model: the first replaces the usual Skyrme term with a term that is sixth order in derivatives, and the second includes a potential that is quartic in the pion fields. Solitons in the first model are shown to deviate significantly from ansätze previously assumed in the literature. The binding energies obtained in both models are lower than those obtained from the standard Skyrme model, and those obtained in the second model are close to the experimental values.

  15. Cellulose binding domain fusion proteins

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1998-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  16. When is protein binding important?

    Science.gov (United States)

    Heuberger, Jules; Schmidt, Stephan; Derendorf, Hartmut

    2013-09-01

    The present paper is an ode to a classic citation by Benet and Hoener (2002. Clin Pharm Ther 71(3):115-121). The now classic paper had a huge impact on drug development and the way the issue of protein binding is perceived and interpreted. Although the authors very clearly pointed out the limitations and underlying assumptions for their delineations, these are too often overlooked and the classic paper's message is misinterpreted by broadening to cases that were not intended. Some members of the scientific community concluded from the paper that protein binding is not important. This was clearly not intended by the authors, as they finished their paper with a paragraph entitled: "When is protein binding important?" Misinterpretation of the underlying assumptions in the classic work can result in major pitfalls in drug development. Therefore, we revisit the topic of protein binding with the intention of clarifying when clinically relevant changes should be considered during drug development. Copyright © 2013 Wiley Periodicals, Inc.

  17. Probing protein phosphatase substrate binding

    DEFF Research Database (Denmark)

    Højlys-Larsen, Kim B.; Sørensen, Kasper Kildegaard; Jensen, Knud Jørgen

    2012-01-01

    Proteomics and high throughput analysis for systems biology can benefit significantly from solid-phase chemical tools for affinity pull-down of proteins from complex mixtures. Here we report the application of solid-phase synthesis of phosphopeptides for pull-down and analysis of the affinity...... profile of the integrin-linked kinase associated phosphatase (ILKAP), a member of the protein phosphatase 2C (PP2C) family. Phosphatases can potentially dephosphorylate these phosphopeptide substrates but, interestingly, performing the binding studies at 4 °C allowed efficient binding to phosphopeptides......, without the need for phosphopeptide mimics or phosphatase inhibitors. As no proven ILKAP substrates were available, we selected phosphopeptide substrates among known PP2Cδ substrates including the protein kinases: p38, ATM, Chk1, Chk2 and RSK2 and synthesized directly on PEGA solid supports through a BAL...

  18. Human plasminogen binding protein tetranectin

    DEFF Research Database (Denmark)

    Kastrup, J S; Rasmussen, H; Nielsen, B B

    1997-01-01

    The recombinant human plasminogen binding protein tetranectin (TN) and the C-type lectin CRD of this protein (TN3) have been crystallized. TN3 crystallizes in the tetragonal space group P4(2)2(1)2 with cell dimensions a = b = 64.0, c = 75.7 A and with one molecule per asymmetric unit. The crystals...... to at least 2.5 A. A full data set has been collected to 3.0 A. The asymmetric unit contains one monomer of TN. Molecular replacement solutions for TN3 and TN have been obtained using the structure of the C-type lectin CRD of rat mannose-binding protein as search model. The rhombohedral space group indicates...

  19. Ligand binding by PDZ domains

    DEFF Research Database (Denmark)

    Chi, Celestine N.; Bach, Anders; Strømgaard, Kristian

    2012-01-01

    , for example, are particularly rich in these domains. The general function of PDZ domains is to bring proteins together within the appropriate cellular compartment, thereby facilitating scaffolding, signaling, and trafficking events. The many functions of PDZ domains under normal physiological as well...... as pathological conditions have been reviewed recently. In this review, we focus on the molecular details of how PDZ domains bind their protein ligands and their potential as drug targets in this context....

  20. Calcium binding by dietary fibre

    International Nuclear Information System (INIS)

    James, W.P.T.; Branch, W.J.; Southgate, D.A.T.

    1978-01-01

    Dietary fibre from plants low in phytate bound calcium in proportion to its uronic-acid content. This binding by the non-cellulosic fraction of fibre reduces the availability of calcium for small-intestinal absorption, but the colonic microbial digestion of uronic acids liberates the calcium. Thus the ability to maintain calcium balance on high-fibre diets may depend on the adaptive capacity on the colon for calcium. (author)

  1. Material Binding Peptides for Nanotechnology

    Directory of Open Access Journals (Sweden)

    Urartu Ozgur Safak Seker

    2011-02-01

    Full Text Available Remarkable progress has been made to date in the discovery of material binding peptides and their utilization in nanotechnology, which has brought new challenges and opportunities. Nowadays phage display is a versatile tool, important for the selection of ligands for proteins and peptides. This combinatorial approach has also been adapted over the past decade to select material-specific peptides. Screening and selection of such phage displayed material binding peptides has attracted great interest, in particular because of their use in nanotechnology. Phage display selected peptides are either synthesized independently or expressed on phage coat protein. Selected phage particles are subsequently utilized in the synthesis of nanoparticles, in the assembly of nanostructures on inorganic surfaces, and oriented protein immobilization as fusion partners of proteins. In this paper, we present an overview on the research conducted on this area. In this review we not only focus on the selection process, but also on molecular binding characterization and utilization of peptides as molecular linkers, molecular assemblers and material synthesizers.

  2. Anion binding in biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Feiters, Martin C [Department of Organic Chemistry, Institute for Molecules and Materials, Faculty of Science, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Meyer-Klaucke, Wolfram [EMBL Hamburg Outstation at DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Kostenko, Alexander V; Soldatov, Alexander V [Faculty of Physics, Southern Federal University, Sorge 5, Rostov-na-Donu, 344090 (Russian Federation); Leblanc, Catherine; Michel, Gurvan; Potin, Philippe [Centre National de la Recherche Scientifique and Universite Pierre et Marie Curie Paris-VI, Station Biologique de Roscoff, Place Georges Teissier, BP 74, F-29682 Roscoff cedex, Bretagne (France); Kuepper, Frithjof C [Scottish Association for Marine Science, Dunstaffnage Marine Laboratory, Oban, Argyll PA37 1QA, Scotland (United Kingdom); Hollenstein, Kaspar; Locher, Kaspar P [Institute of Molecular Biology and Biophysics, ETH Zuerich, Schafmattstrasse 20, Zuerich, 8093 (Switzerland); Bevers, Loes E; Hagedoorn, Peter-Leon; Hagen, Wilfred R, E-mail: m.feiters@science.ru.n [Department of Biotechnology, Delft University of Technology, Julianalaan 67, 2628 BC Delft (Netherlands)

    2009-11-15

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L{sub 3} (2p{sub 3/2}) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  3. Anion binding in biological systems

    International Nuclear Information System (INIS)

    Feiters, Martin C; Meyer-Klaucke, Wolfram; Kostenko, Alexander V; Soldatov, Alexander V; Leblanc, Catherine; Michel, Gurvan; Potin, Philippe; Kuepper, Frithjof C; Hollenstein, Kaspar; Locher, Kaspar P; Bevers, Loes E; Hagedoorn, Peter-Leon; Hagen, Wilfred R

    2009-01-01

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L 3 (2p 3/2 ) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  4. Anion binding in biological systems

    Science.gov (United States)

    Feiters, Martin C.; Meyer-Klaucke, Wolfram; Kostenko, Alexander V.; Soldatov, Alexander V.; Leblanc, Catherine; Michel, Gurvan; Potin, Philippe; Küpper, Frithjof C.; Hollenstein, Kaspar; Locher, Kaspar P.; Bevers, Loes E.; Hagedoorn, Peter-Leon; Hagen, Wilfred R.

    2009-11-01

    We compare aspects of biological X-ray absorption spectroscopy (XAS) studies of cations and anions, and report on some examples of anion binding in biological systems. Brown algae such as Laminaria digitata (oarweed) are effective accumulators of I from seawater, with tissue concentrations exceeding 50 mM, and the vanadate-containing enzyme haloperoxidase is implicated in halide accumulation. We have studied the chemical state of iodine and its biological role in Laminaria at the I K edge, and bromoperoxidase from Ascophyllum nodosum (knotted wrack) at the Br K edge. Mo is essential for many forms of life; W only for certain archaea, such as Archaeoglobus fulgidus and the hyperthermophilic archaeon Pyrococcus furiosus, and some bacteria. The metals are bound and transported as their oxo-anions, molybdate and tungstate, which are similar in size. The transport protein WtpA from P. furiosus binds tungstate more strongly than molybdate, and is related in sequence to Archaeoglobus fulgidus ModA, of which a crystal structure is known. We have measured A. fulgidus ModA with tungstate at the W L3 (2p3/2) edge, and compared the results with the refined crystal structure. XAS studies of anion binding are feasible even if only weak interactions are present, are biologically relevant, and give new insights in the spectroscopy.

  5. Solute-vacancy binding in aluminum

    International Nuclear Information System (INIS)

    Wolverton, C.

    2007-01-01

    Previous efforts to understand solute-vacancy binding in aluminum alloys have been hampered by a scarcity of reliable, quantitative experimental measurements. Here, we report a large database of solute-vacancy binding energies determined from first-principles density functional calculations. The calculated binding energies agree well with accurate measurements where available, and provide an accurate predictor of solute-vacancy binding in other systems. We find: (i) some common solutes in commercial Al alloys (e.g., Cu and Mg) possess either very weak (Cu), or even repulsive (Mg), binding energies. Hence, we assert that some previously reported large binding energies for these solutes are erroneous. (ii) Large binding energies are found for Sn, Cd and In, confirming the proposed mechanism for the reduced natural aging in Al-Cu alloys containing microalloying additions of these solutes. (iii) In addition, we predict that similar reduction in natural aging should occur with additions of Si, Ge and Au. (iv) Even larger binding energies are found for other solutes (e.g., Pb, Bi, Sr, Ba), but these solutes possess essentially no solubility in Al. (v) We have explored the physical effects controlling solute-vacancy binding in Al. We find that there is a strong correlation between binding energy and solute size, with larger solute atoms possessing a stronger binding with vacancies. (vi) Most transition-metal 3d solutes do not bind strongly with vacancies, and some are even energetically strongly repelled from vacancies, particularly for the early 3d solutes, Ti and V

  6. Polymeric competitive protein binding adsorbents for radioassay

    International Nuclear Information System (INIS)

    Adams, R.J.

    1976-01-01

    Serum protein comprising specific binding proteins such as antibodies, B 12 intrinsic factor, thyroxin binding globulin and the like may be copolymerized with globulin constituents of serum by the action of ethylchloroformate to form readily packed insoluble precipitates which, following purification as by washing, are eminently suited for employment as competitive binding protein absorbents in radioassay procedures. 10 claims, no drawings

  7. Insulin binding to individual rat skeletal muscles

    International Nuclear Information System (INIS)

    Koerker, D.J.; Sweet, I.R.; Baskin, D.G.

    1990-01-01

    Studies of insulin binding to skeletal muscle, performed using sarcolemmal membrane preparations or whole muscle incubations of mixed muscle or typical red (soleus, psoas) or white [extensor digitorum longus (EDL), gastrocnemius] muscle, have suggested that red muscle binds more insulin than white muscle. We have evaluated this hypothesis using cryostat sections of unfixed tissue to measure insulin binding in a broad range of skeletal muscles; many were of similar fiber-type profiles. Insulin binding per square millimeter of skeletal muscle slice was measured by autoradiography and computer-assisted densitometry. We found a 4.5-fold range in specific insulin tracer binding, with heart and predominantly slow-twitch oxidative muscles (SO) at the high end and the predominantly fast-twitch glycolytic (FG) muscles at the low end of the range. This pattern reflects insulin sensitivity. Evaluation of displacement curves for insulin binding yielded linear Scatchard plots. The dissociation constants varied over a ninefold range (0.26-2.06 nM). Binding capacity varied from 12.2 to 82.7 fmol/mm2. Neither binding parameter was correlated with fiber type or insulin sensitivity; e.g., among three muscles of similar fiber-type profile, the EDL had high numbers of low-affinity binding sites, whereas the quadriceps had low numbers of high-affinity sites. In summary, considerable heterogeneity in insulin binding was found among hindlimb muscles of the rat, which can be attributed to heterogeneity in binding affinities and the numbers of binding sites. It can be concluded that a given fiber type is not uniquely associated with a set of insulin binding parameters that result in high or low binding

  8. Adaptive evolution of transcription factor binding sites

    Directory of Open Access Journals (Sweden)

    Berg Johannes

    2004-10-01

    Full Text Available Abstract Background The regulation of a gene depends on the binding of transcription factors to specific sites located in the regulatory region of the gene. The generation of these binding sites and of cooperativity between them are essential building blocks in the evolution of complex regulatory networks. We study a theoretical model for the sequence evolution of binding sites by point mutations. The approach is based on biophysical models for the binding of transcription factors to DNA. Hence we derive empirically grounded fitness landscapes, which enter a population genetics model including mutations, genetic drift, and selection. Results We show that the selection for factor binding generically leads to specific correlations between nucleotide frequencies at different positions of a binding site. We demonstrate the possibility of rapid adaptive evolution generating a new binding site for a given transcription factor by point mutations. The evolutionary time required is estimated in terms of the neutral (background mutation rate, the selection coefficient, and the effective population size. Conclusions The efficiency of binding site formation is seen to depend on two joint conditions: the binding site motif must be short enough and the promoter region must be long enough. These constraints on promoter architecture are indeed seen in eukaryotic systems. Furthermore, we analyse the adaptive evolution of genetic switches and of signal integration through binding cooperativity between different sites. Experimental tests of this picture involving the statistics of polymorphisms and phylogenies of sites are discussed.

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

    Science.gov (United States)

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

    2017-06-01

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

  10. Synthetic LPS-Binding Polymer Nanoparticles

    Science.gov (United States)

    Jiang, Tian

    Lipopolysaccharide (LPS), one of the principal components of most gram-negative bacteria's outer membrane, is a type of contaminant that can be frequently found in recombinant DNA products. Because of its strong and even lethal biological effects, selective LPS removal from bioproducts solution is of particular importance in the pharmaceutical and health care industries. In this thesis, for the first time, a proof-of-concept study on preparing LPS-binding hydrogel-like NPs through facile one-step free-radical polymerization was presented. With the incorporation of various hydrophobic (TBAm), cationic (APM, GUA) monomers and cross-linkers (BIS, PEG), a small library of NPs was constructed. Their FITC-LPS binding behaviors were investigated and compared with those of commercially available LPS-binding products. Moreover, the LPS binding selectivity of the NPs was also explored by studying the NPs-BSA interactions. The results showed that all NPs obtained generally presented higher FITC-LPS binding capacity in lower ionic strength buffer than higher ionic strength. However, unlike commercial poly-lysine cellulose and polymyxin B agarose beads' nearly linear increase of FITC-LPS binding with particle concentration, NPs exhibited serious aggregation and the binding quickly saturated or even decreased at high particle concentration. Among various types of NPs, higher FITC-LPS binding capacity was observed for those containing more hydrophobic monomers (TBAm). However, surprisingly, more cationic NPs with higher content of APM exhibited decreased FITC-LPS binding in high ionic strength conditions. Additionally, when new cationic monomer and cross-linker, GUA and PEG, were applied to replace APM and BIS, the obtained NPs showed improved FITC-LPS binding capacity at low NP concentration. But compared with APM- and BIS-containing NPs, the FITC-LPS binding capacity of GUA- and PEG-containing NPs saturated earlier. To investigate the NPs' binding to proteins, we tested the NPs

  11. Sex hormone binding globulin phenotypes

    DEFF Research Database (Denmark)

    Cornelisse, M M; Bennett, Patrick; Christiansen, M

    1994-01-01

    Human sex hormone binding globulin (SHBG) is encoded by a normal and a variant allele. The resulting SHBG phenotypes (the homozygous normal SHBG, the heterozygous SHBG and the homozygous variant SHBG phenotype) can be distinguished by their electrophoretic patterns. We developed a novel detection....... This method of detection was used to determine the distribution of SHBG phenotypes in healthy controls of both sexes and in five different pathological conditions characterized by changes in the SHBG level or endocrine disturbances (malignant and benign ovarian neoplasms, hirsutism, liver cirrhosis...... on the experimental values. Differences in SHBG phenotypes do not appear to have any clinical significance and no sex difference was found in the SHBG phenotype distribution....

  12. DNA Binding Hydroxyl Radical Probes.

    Science.gov (United States)

    Tang, Vicky J; Konigsfeld, Katie M; Aguilera, Joe A; Milligan, Jamie R

    2012-01-01

    The hydroxyl radical is the primary mediator of DNA damage by the indirect effect of ionizing radiation. It is a powerful oxidizing agent produced by the radiolysis of water and is responsible for a significant fraction of the DNA damage associated with ionizing radiation. There is therefore an interest in the development of sensitive assays for its detection. The hydroxylation of aromatic groups to produce fluorescent products has been used for this purpose. We have examined four different chromophores which produce fluorescent products when hydroxylated. Of these, the coumarin system suffers from the fewest disadvantages. We have therefore examined its behavior when linked to a cationic peptide ligand designed to bind strongly to DNA.

  13. Asymmetric cation-binding catalysis

    DEFF Research Database (Denmark)

    Oliveira, Maria Teresa; Lee, Jiwoong

    2017-01-01

    The employment of metal salts is quite limited in asymmetric catalysis, although it would provide an additional arsenal of safe and inexpensive reagents to create molecular functions with high optical purity. Cation chelation by polyethers increases the salts' solubility in conventional organic...... solvents, thus increasing their applicability in synthesis. The expansion of this concept to chiral polyethers led to the emergence of asymmetric cation-binding catalysis, where chiral counter anions are generated from metal salts, particularly using BINOL-based polyethers. Alkali metal salts, namely KF...... highly enantioselective silylation reactions in polyether-generated chiral environments, and leading to a record-high turnover in asymmetric organocatalysis. This can lead to further applications by the asymmetric use of other inorganic salts in various organic transformations....

  14. The helical structure of DNA facilitates binding

    International Nuclear Information System (INIS)

    Berg, Otto G; Mahmutovic, Anel; Marklund, Emil; Elf, Johan

    2016-01-01

    The helical structure of DNA imposes constraints on the rate of diffusion-limited protein binding. Here we solve the reaction–diffusion equations for DNA-like geometries and extend with simulations when necessary. We find that the helical structure can make binding to the DNA more than twice as fast compared to a case where DNA would be reactive only along one side. We also find that this rate advantage remains when the contributions from steric constraints and rotational diffusion of the DNA-binding protein are included. Furthermore, we find that the association rate is insensitive to changes in the steric constraints on the DNA in the helix geometry, while it is much more dependent on the steric constraints on the DNA-binding protein. We conclude that the helical structure of DNA facilitates the nonspecific binding of transcription factors and structural DNA-binding proteins in general. (paper)

  15. Fundamental considerations in ski binding analysis.

    Science.gov (United States)

    Mote, C D; Hull, M L

    1976-01-01

    1. The static adjustment of a ski binding by hand or by available machines is only an adjustment and is neither a static nor a dynamic evaluation of the binding design. Bindings of different design with identical static adjustments will perform differently in environments in which the forces are static or dynamic. 2. The concept of binding release force is a useful measure of binding adjustment, but it is inappropriate as a criterion for binding evaluation. First, it does not direct attention toward the injury causing mechanism, strain, or displacement in the leg. Second, it is only part of the evaluation in dynamic problems. 3. The binding release decision in present bindings is displacement controlled. The relative displacement of the boot and ski is the system variable. For any specified relative displacement the binding force can be any of an infinite number of possibilities determined by the loading path. 4. The response of the leg-ski system to external impulses applied to the ski is independent of the boot-ski relative motion as long as the boot recenters quickly in the binding. Response is dependent upon the external impulse plus system inertia, damping and stiffness. 5. When tested under half sinusoidal forces applied to a test ski, all bindings will demonstrate static and impulse loading regions. In the static region the force drives the binding to a relative release displacement. In the impulse region the initial velocity of the ski drives the binding to a release displacement. 6. The transition between the static and impulse loading regions is determined by the binding's capacity to store and dissipate energy along the principal loading path. Increased energy capacity necessitates larger external impulses to produce release. 7. In all bindings examined to date, the transmitted leg displacement or strain at release under static loading exceeds leg strain under dynamic or impact loading. Because static loading is responsible for many injuries, a skier

  16. Lead-Binding Proteins: A Review

    Directory of Open Access Journals (Sweden)

    Harvey C. Gonick

    2011-01-01

    Full Text Available Lead-binding proteins are a series of low molecular weight proteins, analogous to metallothionein, which segregate lead in a nontoxic form in several organs (kidney, brain, lung, liver, erythrocyte. Whether the lead-binding proteins in every organ are identical or different remains to be determined. In the erythrocyte, delta-aminolevulinic acid dehydratase (ALAD isoforms have commanded the greatest attention as proteins and enzymes that are both inhibitable and inducible by lead. ALAD-2, although it binds lead to a greater degree than ALAD-1, appears to bind lead in a less toxic form. What may be of greater significance is that a low molecular weight lead-binding protein, approximately 10 kDa, appears in the erythrocyte once blood lead exceeds 39 μg/dL and eventually surpasses the lead-binding capacity of ALAD. In brain and kidney of environmentally exposed humans and animals, a cytoplasmic lead-binding protein has been identified as thymosin β4, a 5 kDa protein. In kidney, but not brain, another lead-binding protein has been identified as acyl-CoA binding protein, a 9 kDa protein. Each of these proteins, when coincubated with liver ALAD and titrated with lead, diminishes the inhibition of ALAD by lead, verifying their ability to segregate lead in a nontoxic form.

  17. Drug binding properties of neonatal albumin

    DEFF Research Database (Denmark)

    Brodersen, R; Honoré, B

    1989-01-01

    Neonatal and adult albumin was isolated by gel chromatography on Sephacryl S-300, from adult and umbilical cord serum, respectively. Binding of monoacetyl-diamino-diphenyl sulfone, warfarin, sulfamethizole, and diazepam was studied by means of equilibrium dialysis and the binding data were analyzed...... by the method of several acceptable fitted curves. It was found that the binding affinity to neonatal albumin is less than to adult albumin for monoacetyl-diamino-diphenyl sulfone and warfarin. Sulfamethizole binding to the neonatal protein is similarly reduced when more than one molecule of the drug is bound...

  18. Bitopic Ligands and Metastable Binding Sites

    DEFF Research Database (Denmark)

    Fronik, Philipp; Gaiser, Birgit I; Sejer Pedersen, Daniel

    2017-01-01

    of orthosteric binding sites. Bitopic ligands have been employed to address the selectivity problem by combining (linking) an orthosteric ligand with an allosteric modulator, theoretically leading to high-affinity subtype selective ligands. However, it remains a challenge to identify suitable allosteric binding...... that have been reported to date, this type of bitopic ligands would be composed of two identical pharmacophores. Herein, we outline the concept of bitopic ligands, review metastable binding sites, and discuss their potential as a new source of allosteric binding sites....

  19. Retinoid-binding proteins: similar protein architectures bind similar ligands via completely different ways.

    Directory of Open Access Journals (Sweden)

    Yu-Ru Zhang

    Full Text Available BACKGROUND: Retinoids are a class of compounds that are chemically related to vitamin A, which is an essential nutrient that plays a key role in vision, cell growth and differentiation. In vivo, retinoids must bind with specific proteins to perform their necessary functions. Plasma retinol-binding protein (RBP and epididymal retinoic acid binding protein (ERABP carry retinoids in bodily fluids, while cellular retinol-binding proteins (CRBPs and cellular retinoic acid-binding proteins (CRABPs carry retinoids within cells. Interestingly, although all of these transport proteins possess similar structures, the modes of binding for the different retinoid ligands with their carrier proteins are different. METHODOLOGY/PRINCIPAL FINDINGS: In this work, we analyzed the various retinoid transport mechanisms using structure and sequence comparisons, binding site analyses and molecular dynamics simulations. Our results show that in the same family of proteins and subcellular location, the orientation of a retinoid molecule within a binding protein is same, whereas when different families of proteins are considered, the orientation of the bound retinoid is completely different. In addition, none of the amino acid residues involved in ligand binding is conserved between the transport proteins. However, for each specific binding protein, the amino acids involved in the ligand binding are conserved. The results of this study allow us to propose a possible transport model for retinoids. CONCLUSIONS/SIGNIFICANCE: Our results reveal the differences in the binding modes between the different retinoid-binding proteins.

  20. Myocardial Tbx20 regulates early atrioventricular canal formation and endocardial epithelial-mesenchymal transition via Bmp2

    NARCIS (Netherlands)

    Cai, Xiaoqiang; Nomura-Kitabayashi, Aya; Cai, Weibin; Yan, Jianyun; Christoffels, Vincent M.; Cai, Chen-Leng

    2011-01-01

    During early embryogenesis, the formation of the cardiac atrioventricular canal (AVC) facilitates the transition of the heart from a linear tube into a chambered organ. However, the genetic pathways underlying this developmental process are poorly understood. The T-box transcription factor Tbx20 is

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

    Science.gov (United States)

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

    2017-05-01

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

  2. E. coli-Produced BMP-2 as a Chemopreventive Strategy for Colon Cancer : A Proof-of-Concept Study

    NARCIS (Netherlands)

    Yuvaraj, Saravanan; Al-Lahham, Sa'ad H.; Somasundaram, Rajesh; Figaroa, Patrick A.; Peppelenbosch, Maikel P.; Bos, Nicolaas A.

    2012-01-01

    Colon cancer is a serious health problem, and novel preventive and therapeutical avenues are urgently called for. Delivery of proteins with anticancer activity through genetically modified bacteria provides an interesting, potentially specific, economic and effective approach here. Interestingly,

  3. In Vitro Evaluation of an Injectable Chitosan Gel for Sustained Local Delivery of BMP-2 for Osteoblastic Differentiation

    Science.gov (United States)

    2011-11-01

    In vitro cellular responses to scaffolds containing two microencapsulated growth factors. Biomaterials 2009;30:5215–5224. 16. Park KH, Kim H, Moon S...applications. Eur. J Pharm Biopharm 2004;57:19–34. 32. Ren D, Yi H, Wang W, Ma X. The enzymatic degradation and swelling properties of chitosan

  4. Regulation of Axolotl (Ambystoma mexicanum) Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Science.gov (United States)

    Lehrberg, Jeffrey; Gardiner, David M

    2015-01-01

    We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  5. Regulation of Axolotl (Ambystoma mexicanum Limb Blastema Cell Proliferation by Nerves and BMP2 in Organotypic Slice Culture.

    Directory of Open Access Journals (Sweden)

    Jeffrey Lehrberg

    Full Text Available We have modified and optimized the technique of organotypic slice culture in order to study the mechanisms regulating growth and pattern formation in regenerating axolotl limb blastemas. Blastema cells maintain many of the behaviors that are characteristic of blastemas in vivo when cultured as slices in vitro, including rates of proliferation that are comparable to what has been reported in vivo. Because the blastema slices can be cultured in basal medium without fetal bovine serum, it was possible to test the response of blastema cells to signaling molecules present in serum, as well as those produced by nerves. We also were able to investigate the response of blastema cells to experimentally regulated changes in BMP signaling. Blastema cells responded to all of these signals by increasing the rate of proliferation and the level of expression of the blastema marker gene, Prrx-1. The organotypic slice culture model provides the opportunity to identify and characterize the spatial and temporal co-regulation of pathways in order to induce and enhance a regenerative response.

  6. Methods to Analyze Bone Regenerative Response to Different rhBMP-2 Doses in Rabbit Craniofacial Defects

    Science.gov (United States)

    2014-02-28

    Ruggiero, S., Fantasia, J., Burakoff, R., Moorji, S.M., Paric, E., et al. Sonic hedgehog gene enhanced tissue engineering for bone regeneration. Gene Ther...discectomy and fusion: a case study. Spine J 7, 235, 2007. 8. Zara, J.N., Siu, R.K., Zhang, X., Shen, J., Ngo, R., Lee, M., et al. High doses of bone

  7. O uso de rhBMP-2 para aumento ósseo maxilar: relato de caso clínico

    OpenAIRE

    Freitas, Rubens; Spin Neto, Rubens; Marcantonio, Claudio [UNESP; Marcantonio, Rosemary Adriana Chierici [UNESP; Pereira, Luis Antonio Violin Dias; Marcantonio Júnior, Elcio [UNESP

    2012-01-01

    The bone resorption in the anterior maxilla, due to its aesthetic importance, can be considered one of the challenges in implant dentistry. Autogenous bone graft is the most indicated bone augmentation procedure, aiming an implant supported rehabilitation.. Alternatively, some other graft procedures can be done with homogenous and xenogenous bone graft, biomaterials and different associations. Additionally to the mentioned biomaterials, the bone morphogenetic protein (BMP), specially the rhBM...

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

    Science.gov (United States)

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

    2016-04-01

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

  9. New DNA-binding radioprotectors

    Science.gov (United States)

    Martin, Roger

    The normal tissue damage associated with cancer radiotherapy has motivated the development at Peter Mac of a new class of DNA-binding radioprotecting drugs that could be applied top-ically to normal tissues at risk. Methylproamine (MP), the lead compound, reduces radiation induced cell kill at low concentrations. For example, experiments comparing the clonogenic survival of transformed human keratinocytes treated with 30 micromolar MP before and dur-ing various doses of ionising radiation, with the radiation dose response for untreated cells, indicate a dose reduction factor (DRF) of 2. Similar survival curve experiments using various concentrations of MP, with parallel measurements of uptake of MP into cell nuclei, have en-abled the relationship between drug uptake and extent of radioprotection to be established. Radioprotection has also been demonstrated after systemic administration to mice, for three different endpoints, namely lung, jejunum and bone marrow (survival at 30 days post-TBI). The results of pulse radiolysis studies indicated that the drugs act by reduction of transient radiation-induced oxidative species on DNA. This hypothesis was substantiated by the results of experiments in which MP radioprotection of radiation-induced DNA double-strand breaks, assessed as -H2AX foci, in the human keratinocyte cell line. For both endpoints, the extent of radioprotection increased with MP concentration up to a maximal value. These results are consistent with the hypothesis that radioprotection by MP is mediated by attenuation of the extent of initial DNA damage. However, although MP is a potent radioprotector, it becomes cytotoxic at higher concentrations. This limitation has been addressed in an extensive program of lead optimisation and some promising analogues have emerged from which the next lead will be selected. Given the clinical potential of topical radioprotection, the new analogues are being assessed in terms of delivery to mouse oral mucosa. This is

  10. Binding of (/sup 3/H)imipramine to human platelet membranes with compensation for saturable binding to filters and its implication for binding studies with brain membranes

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, O.M.; Wood, K.M.; Williams, D.C.

    1984-08-01

    Apparent specific binding of (/sup 3/H)imipramine to human platelet membranes at high concentrations of imipramine showed deviation from that expected of a single binding site, a result consistent with a low-affinity binding site. The deviation was due to displaceable, saturable binding to the glass fibre filters used in the assays. Imipramine, chloripramine, desipramine, and fluoxetine inhibited binding to filters whereas 5-hydroxytryptamine and ethanol were ineffective. Experimental conditions were developed that eliminated filter binding, allowing assay of high- and low-affinity binding to membranes. Failure to correct for filter binding may lead to overestimation of binding parameters, Bmax and KD for high-affinity binding to membranes, and may also be misinterpreted as indicating a low-affinity binding component in both platelet and brain membranes. Low-affinity binding (KD less than 2 microM) of imipramine to human platelet membranes was demonstrated and its significance discussed.

  11. Msx and dlx homeogene expression in epithelial odontogenic tumors.

    Science.gov (United States)

    Ruhin-Poncet, Blandine; Ghoul-Mazgar, Sonia; Hotton, Dominique; Capron, Frédérique; Jaafoura, Mohamed Habib; Goubin, Gérard; Berdal, Ariane

    2009-01-01

    Epithelial odontogenic tumors are rare jaw pathologies that raise clinical diagnosis and prognosis dilemmas notably between ameloblastomas and clear cell odontogenic carcinomas (CCOCs). In line with previous studies, the molecular determinants of tooth development-amelogenin, Msx1, Msx2, Dlx2, Dlx3, Bmp2, and Bmp4-were analyzed by RT-PCR, ISH, and immunolabeling in 12 recurrent ameloblastomas and in one case of CCOC. Although Msx1 expression imitates normal cell differentiation in these tumors, other genes showed a distinct pattern depending on the type of tumor and the tissue involved. In benign ameloblastomas, ISH localized Dlx3 transcripts and inconstantly detected Msx2 transcripts in epithelial cells. In the CCOC, ISH established a lack of both Dlx3 and Msx2 transcripts but allowed identification of the antisense transcript of Msx1, which imitates the same scheme of distribution between mesenchyme and epithelium as in the cup stage of tooth development. Furthermore, while exploring the expression pattern of signal molecules by RT-PCR, Bmp2 was shown to be completely inactivated in the CCOC and irregularly noticeable in ameloblastomas. Bmp4 was always expressed in all the tumors. Based on the established roles of Msx and Dlx transcription factors in dental cell fates, these data suggest that their altered expression is a proposed trail to explain the genesis and/or the progression of odontogenic tumors.

  12. Multiple binding modes of ibuprofen in human serum albumin identified by absolute binding free energy calculations

    KAUST Repository

    Evoli, Stefania

    2016-11-10

    Human serum albumin possesses multiple binding sites and transports a wide range of ligands that include the anti-inflammatory drug ibuprofen. A complete map of the binding sites of ibuprofen in albumin is difficult to obtain in traditional experiments, because of the structural adaptability of this protein in accommodating small ligands. In this work, we provide a set of predictions covering the geometry, affinity of binding and protonation state for the pharmaceutically most active form (S-isomer) of ibuprofen to albumin, by using absolute binding free energy calculations in combination with classical molecular dynamics (MD) simulations and molecular docking. The most favorable binding modes correctly reproduce several experimentally identified binding locations, which include the two Sudlow\\'s drug sites (DS2 and DS1) and the fatty acid binding sites 6 and 2 (FA6 and FA2). Previously unknown details of the binding conformations were revealed for some of them, and formerly undetected binding modes were found in other protein sites. The calculated binding affinities exhibit trends which seem to agree with the available experimental data, and drastically degrade when the ligand is modeled in a protonated (neutral) state, indicating that ibuprofen associates with albumin preferentially in its charged form. These findings provide a detailed description of the binding of ibuprofen, help to explain a wide range of results reported in the literature in the last decades, and demonstrate the possibility of using simulation methods to predict ligand binding to albumin.

  13. Thermodynamics of ligand binding to acyl-coenzyme A binding protein studied by titration calorimetry

    DEFF Research Database (Denmark)

    Færgeman, Nils J.; Sigurskjold, B W; Kragelund, B B

    1996-01-01

    Ligand binding to recombinant bovine acyl-CoA binding protein (ACBP) was examined using isothermal microcalorimetry. Microcalorimetric measurements confirm that the binding affinity of acyl-CoA esters for ACBP is strongly dependent on the length of the acyl chain with a clear preference for acyl-...

  14. Identification of Glossina morsitans morsitans odorant binding ...

    African Journals Online (AJOL)

    Tsetse flies are vectors of trypanosome parasites, causative agents of Trypanosomiasis in humans and animals. Odorant Binding Proteins (OBPs) are critical in insect olfaction as they bind volatile odours from the environment and transport them to receptors within olfactory receptor neurons for processing providing critical ...

  15. Triazatriangulene as binding group for molecular electronics

    DEFF Research Database (Denmark)

    Wei, Zhongming; Wang, Xintai; Borges, Anders

    2014-01-01

    The triazatriangulene (TATA) ring system was investigated as a binding group for tunnel junctions of molecular wires on gold surfaces. Self-assembled monolayers (SAMs) of TATA platforms with three different lengths of phenylene wires were fabricated, and their electrical conductance was recorded ...... with its high stability and directionality make this binding group very attractive for molecular electronic measurements and devices. (Figure Presented)....

  16. Localization-enhanced biexciton binding in semiconductors

    DEFF Research Database (Denmark)

    Langbein, Wolfgang Werner; Hvam, Jørn Märcher

    1999-01-01

    The influence of excitonic localization on the binding energy of biexcitons is investigated for quasi-three-dimensional and quasi-two-dimensional AlxGa1-xAs structures. An increase of the biexciton binding energy is observed for localization energies comparable to or larger than the free biexcito...

  17. Binding of corroded ions to human saliva.

    Science.gov (United States)

    Mueller, H J

    1985-05-01

    Employing equilibrium dialysis, the binding abilities of Cu, Al, Co and Cr ions from corroded Cu-Al and Co-Cr dental casting alloys towards human saliva and two of its gel chromatographic fractions were determined. Results indicate that both Cu and Co bind to human saliva i.e. 0.045 and 0.027 mg/mg protein, respectively. Besides possessing the largest binding ability, Cu also possessed the largest binding capacity. The saturation of Cu binding was not reached up to the limit of 0.35 mg protein/ml employed in the tests, while Co reached full saturation at about 0.2 mg protein/ml. Chromium showed absolutely no binding to human saliva while Al ions did not pass through the dialysis membranes. Compared to the binding with solutions that were synthetically made up to contain added salivary-type proteins, it is shown that the binding to human saliva is about 1 order of magnitude larger, at least for Cu ions.

  18. Intentional binding of visual effects.

    Science.gov (United States)

    Ruess, Miriam; Thomaschke, Roland; Kiesel, Andrea

    2018-04-01

    When an action produces an effect, the effect is perceived earlier in time compared to a stimulus without preceding action. This temporal bias is called intentional binding (IB) and serves as an implicit measure of sense of agency. Typically, IB is investigated by presenting a rotating clock hand while participants execute an action and perceive a resulting tone. Participants are asked to estimate the time point of tone onset by referring to the clock hand position. This time point estimate is compared to a time point estimate of a tone in a condition in which the tone occurs without preceding action. Studies employing this classic clock paradigm employed auditory action effects. We modified this paradigm to investigate potential IB of visual action effects, and, additionally, to investigate how IB differs for visual action effects (Experiment 1) in comparison to auditory action effects (Experiment 2). Our results show that, like the IB of an auditory effect, the time point of a visual action effect is shifted toward the causing action, and that the size of the IB depends on the delay duration of the effect. Comparable to auditory action effects, earlier action effects showed stronger IB compared to later action effects. Yet overall IB of the visual effects was weaker than IB of the auditory effects. As IB is seen as an indicator of sense of agency, this may have important implications for the design of human-machine interfaces.

  19. Characterization of chlorophyll binding to LIL3.

    Science.gov (United States)

    Mork-Jansson, Astrid Elisabeth; Eichacker, Lutz Andreas

    2018-01-01

    The light harvesting like protein 3 (LIL 3) from higher plants, has been linked to functions in chlorophyll and tocopherol biosynthesis, photo-protection and chlorophyll transfer. However, the binding of chlorophyll to LIL3 is unclear. We present a reconstitution protocol for chlorophyll binding to LIL3 in DDM micelles. It is shown in the absence of lipids and carotenoids that reconstitution of chlorophyll binding to in vitro expressed LIL3 requires pre-incubation of reaction partners at room temperature. We show chlorophyll a but not chlorophyll b binding to LIL3 at a molar ratio of 1:1. Neither dynamic light scattering nor native PAGE, enabled a discrimination between binding of chlorophyll a and/or b to LIL3.

  20. (TH) diazepam binding to human granulocytes

    Energy Technology Data Exchange (ETDEWEB)

    Bond, P.A.; Cundall, R.L.; Rolfe, B.

    1985-07-08

    (TH)-diazepam binds to sites on human granulocyte membranes, with little or no binding to platelets or lymphocytes. These (TH)-diazepam binding sites are of the peripheral type, being strongly inhibited by R05-4864 (Ki=6.23nM) but only weakly by clonazepam (Ki=14 M). Binding of (TH) diazepam at 0 is saturable, specific and stereoselective. Scatchard analysis indicates a single class of sites with Bmax of 109 +/- 17f moles per mg of protein and K/sub D/ of 3.07 +/- 0.53nM. Hill plots of saturation experiments gave straight lines with a mean Hill coefficient of 1.03 +/- 0.014. Binding is time dependent and reversible and it varies linearly with granulocyte protein concentration over the range 0.025-0.300 mg of protein. 11 references, 3 figures, 1 table.

  1. Factor VIIa binding and internalization in hepatocytes

    DEFF Research Database (Denmark)

    Hjortoe, G; Sorensen, B B; Petersen, L C

    2005-01-01

    The liver is believed to be the primary clearance organ for coagulation proteases, including factor VIIa (FVIIa). However, at present, clearance mechanisms for FVIIa in liver are unknown. To obtain information on the FVIIa clearance mechanism, we investigated the binding and internalization...... no effect. HEPG2 cells internalized FVIIa with a rate of 10 fmol 10(-5) cells h(-1). In contrast to HEPG2 cells, FVIIa binding to primary rat hepatocytes was completely independent of TF, and excess unlabeled FVIIa partly reduced the binding of 125I-FVIIa to rat hepatocytes. Further, compared with HEPG2...... cells, three- to fourfold more FVIIa bound to rat primary hepatocytes, and the bound FVIIa was internalized at a faster rate. Similar FVIIa binding and internalization profiles were observed in primary human hepatocytes. Plasma inhibitors had no effect on FVIIa binding and internalization in hepatocytes...

  2. Bone morphogenetic protein-2 functions as a negative regulator in the differentiation of myoblasts, but not as an inducer for the formations of cartilage and bone in mouse embryonic tongue

    Directory of Open Access Journals (Sweden)

    Suzuki Erika

    2011-07-01

    Full Text Available Abstract Background In vitro studies using the myogenic cell line C2C12 demonstrate that bone morphogenetic protein-2 (BMP-2 converts the developmental pathway of C2C12 from a myogenic cell lineage to an osteoblastic cell lineage. Further, in vivo studies using null mutation mice demonstrate that BMPs inhibit the specification of the developmental fate of myogenic progenitor cells. However, the roles of BMPs in the phases of differentiation and maturation in skeletal muscles have yet to be determined. The present study attempts to define the function of BMP-2 in the final stage of differentiation of mouse tongue myoblast. Results Recombinant BMP-2 inhibited the expressions of markers for the differentiation of skeletal muscle cells, such as myogenin, muscle creatine kinase (MCK, and fast myosin heavy chain (fMyHC, whereas BMP-2 siRNA stimulated such markers. Neither the recombinant BMP-2 nor BMP-2 siRNA altered the expressions of markers for the formation of cartilage and bone, such as osteocalcin, alkaline phosphatase (ALP, collagen II, and collagen X. Further, no formation of cartilage and bone was observed in the recombinant BMP-2-treated tongues based on Alizarin red and Alcian blue stainings. Neither recombinant BMP-2 nor BMP-2 siRNA affected the expression of inhibitor of DNA binding/differentiation 1 (Id1. The ratios of chondrogenic and osteogenic markers relative to glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a house keeping gene were approximately 1000-fold lower than those of myogenic markers in the cultured tongue. Conclusions BMP-2 functions as a negative regulator for the final differentiation of tongue myoblasts, but not as an inducer for the formation of cartilage and bone in cultured tongue, probably because the genes related to myogenesis are in an activation mode, while the genes related to chondrogenesis and osteogenesis are in a silencing mode.

  3. Regulation of bone morphogenetic protein signalling and cranial osteogenesis by Gpc1 and Gpc3.

    Science.gov (United States)

    Dwivedi, Prem P; Grose, Randall H; Filmus, Jorge; Hii, Charles S T; Xian, Cory J; Anderson, Peter J; Powell, Barry C

    2013-08-01

    From birth, the vault of the skull grows at a prodigious rate, driven by the activity of osteoblastic cells at the fibrous joints (sutures) that separate the bony calvarial plates. One in 2500 children is born with a medical condition known as craniosynostosis because of premature bony fusion of the calvarial plates and a cessation of bone growth at the sutures. Bone morphogenetic proteins (BMPs) are potent growth factors that promote bone formation. Previously, we found that Glypican-1 (GPC1) and Glypican-3 (GPC3) are expressed in cranial sutures and are decreased during premature suture fusion in children. Although glypicans are known to regulate BMP signalling, a mechanistic link between GPC1, GPC3 and BMPs and osteogenesis has not yet been investigated. We now report that human primary suture mesenchymal cells coexpress GPC1 and GPC3 on the cell surface and release them into the media. We show that they inhibit BMP2, BMP4 and BMP7 activities, which both physically interact with BMP2 and that immunoblockade of endogenous GPC1 and GPC3 potentiates BMP2 activity. In contrast, increased levels of GPC1 and GPC3 as a result of overexpression or the addition of recombinant protein, inhibit BMP2 signalling and BMP2-mediated osteogenesis. We demonstrate that BMP signalling in suture mesenchymal cells is mediated by both SMAD-dependent and SMAD-independent pathways and that GPC1 and GPC3 inhibit both pathways. GPC3 inhibition of BMP2 activity is independent of attachment of the glypican on the cell surface and post-translational glycanation, and thus appears to be mediated by the core glypican protein. The discovery that GPC1 and GPC3 regulate BMP2-mediated osteogenesis, and that inhibition of endogenous GPC1 and GPC3 potentiates BMP2 responsiveness of human suture mesenchymal cells, indicates how downregulation of glypican expression could lead to the bony suture fusion that characterizes craniosynostosis. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    Energy Technology Data Exchange (ETDEWEB)

    Gangi Setty, Thanuja [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Cho, Christine [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Govindappa, Sowmya [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India); Apicella, Michael A. [Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1109 (United States); Ramaswamy, S., E-mail: ramas@instem.res.in [Institute for Stem Cell Biology and Regenerative Medicine, NCBS Campus, GKVK Post, Bangalore, Karnataka 560 065 (India)

    2014-07-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states.

  5. Bacterial periplasmic sialic acid-binding proteins exhibit a conserved binding site

    International Nuclear Information System (INIS)

    Gangi Setty, Thanuja; Cho, Christine; Govindappa, Sowmya; Apicella, Michael A.; Ramaswamy, S.

    2014-01-01

    Structure–function studies of sialic acid-binding proteins from F. nucleatum, P. multocida, V. cholerae and H. influenzae reveal a conserved network of hydrogen bonds involved in conformational change on ligand binding. Sialic acids are a family of related nine-carbon sugar acids that play important roles in both eukaryotes and prokaryotes. These sialic acids are incorporated/decorated onto lipooligosaccharides as terminal sugars in multiple bacteria to evade the host immune system. Many pathogenic bacteria scavenge sialic acids from their host and use them for molecular mimicry. The first step of this process is the transport of sialic acid to the cytoplasm, which often takes place using a tripartite ATP-independent transport system consisting of a periplasmic binding protein and a membrane transporter. In this paper, the structural characterization of periplasmic binding proteins from the pathogenic bacteria Fusobacterium nucleatum, Pasteurella multocida and Vibrio cholerae and their thermodynamic characterization are reported. The binding affinities of several mutations in the Neu5Ac binding site of the Haemophilus influenzae protein are also reported. The structure and the thermodynamics of the binding of sugars suggest that all of these proteins have a very well conserved binding pocket and similar binding affinities. A significant conformational change occurs when these proteins bind the sugar. While the C1 carboxylate has been identified as the primary binding site, a second conserved hydrogen-bonding network is involved in the initiation and stabilization of the conformational states

  6. Specific insulin binding in bovine chromaffin cells; demonstration of preferential binding to adrenalin-storing cells

    International Nuclear Information System (INIS)

    Serck-Hanssen, G.; Soevik, O.

    1987-01-01

    Insulin binding was studied in subpopulations of bovine chromaffin cells enriched in adrenalin-producing cells (A-cells) or noradrenalin-producing cells (NA-cells). Binding of 125 I-insulin was carried out at 15 0 C for 3 hrs in the absence or presence of excess unlabeled hormone. Four fractions of cells were obtained by centrifugation on a stepwise bovine serum albumin gradient. The four fractions were all shown to bind insulin in a specific manner and the highest binding was measured in the cell layers of higher densities, containing mainly A-cells. The difference in binding of insulin to the four subpopulations of chromaffin cells seemed to be related to differences in numbers of receptors as opposed to receptor affinities. The authors conclude that bovine chromaffin cells possess high affinity binding sites for insulin and that these binding sites are mainly confined to A-cells. 24 references, 2 figures, 1 table

  7. Human liver aldehyde dehydrogenase: coenzyme binding

    International Nuclear Information System (INIS)

    Kosley, L.L.; Pietruszko, R.

    1987-01-01

    The binding of [U- 14 C] NAD to mitochondrial (E2) and cytoplasmin(E1) aldehyde dehydrogenase was measured by gel filtration and sedimentation techniques. The binding data for NAD and (E1) yielded linear Scatchard plots giving a dissociation constant of 25 (+/- 8) uM and the stoichiometry of 2 mol of NAD bound per mol of E1. The binding data for NAD and (E2) gave nonlinear Scatchard plots. The binding of NADH to E2 was measured via fluorescence enhancement; this could not be done with E1 because there was no signal. The dissociation constant for E2 by this technique was 0.7 (+/- 0.4) uM and stoichiometry of 1.0 was obtained. The binding of [U- 14 C] NADH to (E1) and (E2) was also measured by the sedimentation technique. The binding data for (E1) and NADH gave linear Scatchard plots giving a dissociation constant of 13 (+/- 6) uM and the stoichiometry of 2.0. The binding data for NADH to (E2) gave nonlinear Scatchard plots. With (E1), the dissociation constants for both NAD and NADH are similar to those determined kinetically, but the stoichiometry is only half of that found by stopped flow technique. With (E2) the dissociation constant by fluorometric procedure was 2 orders of magnitude less than that from catalytic reaction

  8. Increased thyrotropin binding in hyperfunctioning thyroid nodules.

    Science.gov (United States)

    Müller-Gärtner, H W; Schneider, C; Bay, V; Tadt, A; Rehpenning, W; de Heer, K; Jessel, M

    1987-08-01

    The object of this study was to investigate TSH receptors in hyperfunctioning thyroid nodules (HFN). In HFN, obtained from seven patients, 125-I-TSH binding as determined by equilibrium binding analysis on particulate membrane preparations, was found to be significantly increased as compared with normal thyroid tissues (five patients; P less than 0.001). Scatchard analysis of TSH-binding revealed two kinds of binding sites for both normal thyroid tissue and HFN, and displayed significantly increased association constants of high- and low-affinity binding sites in HFN (Ka = 11.75 +/- 6.8 10(9) M-1, P less than 0.001 and Ka = 2.1 +/- 1.0 10(7) M-1, P less than 0.025; x +/- SEM) as compared with normal thyroid tissue (Ka = 0.25 +/- 0.06 10(9) M-1, Ka = 0.14 +/- 0.03 10(7) M-1; x +/- SEM). The capacity of the high-affinity binding sites in HFN was found to be decreased (1.8 +/- 1.1 pmol/mg protein, x +/- SEM) in comparison with normal thyroid tissue (4.26 +/- 1.27 pmol/mg protein; x +/- SEM). TSH-receptor autoradiography applied to cryostatic tissue sections confirmed increased TSH binding of the follicular epithelium in HFN. These data suggest that an increased affinity of TSH-receptor sites in HFN in iodine deficient areas may be an important event in thyroid autonomy.

  9. Measuring Binding Affinity of Protein-Ligand Interaction Using Spectrophotometry: Binding of Neutral Red to Riboflavin-Binding Protein

    Science.gov (United States)

    Chenprakhon, Pirom; Sucharitakul, Jeerus; Panijpan, Bhinyo; Chaiyen, Pimchai

    2010-01-01

    The dissociation constant, K[subscript d], of the binding of riboflavin-binding protein (RP) with neutral red (NR) can be determined by titrating RP to a fixed concentration of NR. Upon adding RP to the NR solution, the maximum absorption peak of NR shifts to 545 nm from 450 nm for the free NR. The change of the absorption can be used to determine…

  10. Hardware device binding and mutual authentication

    Science.gov (United States)

    Hamlet, Jason R; Pierson, Lyndon G

    2014-03-04

    Detection and deterrence of device tampering and subversion by substitution may be achieved by including a cryptographic unit within a computing device for binding multiple hardware devices and mutually authenticating the devices. The cryptographic unit includes a physically unclonable function ("PUF") circuit disposed in or on the hardware device, which generates a binding PUF value. The cryptographic unit uses the binding PUF value during an enrollment phase and subsequent authentication phases. During a subsequent authentication phase, the cryptographic unit uses the binding PUF values of the multiple hardware devices to generate a challenge to send to the other device, and to verify a challenge received from the other device to mutually authenticate the hardware devices.

  11. Peptide binding specificity of the chaperone calreticulin

    DEFF Research Database (Denmark)

    Sandhu, N.; Duus, K.; Jorgensen, C.S.

    2007-01-01

    Calreticulin is a molecular chaperone with specificity for polypeptides and N-linked monoglucosylated glycans. In order to determine the specificity of polypeptide binding, the interaction of calreticulin with polypeptides was investigated using synthetic peptides of different length and composit......Calreticulin is a molecular chaperone with specificity for polypeptides and N-linked monoglucosylated glycans. In order to determine the specificity of polypeptide binding, the interaction of calreticulin with polypeptides was investigated using synthetic peptides of different length...... than 5 amino acids showed binding and a clear correlation with hydrophobicity was demonstrated for oligomers of different hydrophobic amino acids. Insertion of hydrophilic amino acids in a hydrophobic sequence diminished or abolished binding. In conclusion our results show that calreticulin has...

  12. Fatty Acid Binding Proteins in Prostate Cancer

    National Research Council Canada - National Science Library

    Jett, Marti

    2000-01-01

    We have shown that there is a distinct pattern of fatty acid binding protein (FAEP) expression in prostate cancer vs normal cells and that finding has be confirmed in patient samples of biopsy specimens...

  13. Bilirubin Binding Capacity in the Preterm Neonate.

    Science.gov (United States)

    Amin, Sanjiv B

    2016-06-01

    Total serum/plasma bilirubin (TB), the biochemical measure currently used to evaluate and manage hyperbilirubinemia, is not a useful predictor of bilirubin-induced neurotoxicity in premature infants. Altered bilirubin-albumin binding in premature infants limits the usefulness of TB in premature infants. In this article, bilirubin-albumin binding, a modifying factor for bilirubin-induced neurotoxicity, in premature infants is reviewed. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Exciton Binding Energy of Monolayer WS2

    Science.gov (United States)

    Zhu, Bairen; Chen, Xi; Cui, Xiaodong

    2015-03-01

    The optical properties of monolayer transition metal dichalcogenides (TMDC) feature prominent excitonic natures. Here we report an experimental approach to measuring the exciton binding energy of monolayer WS2 with linear differential transmission spectroscopy and two-photon photoluminescence excitation spectroscopy (TP-PLE). TP-PLE measurements show the exciton binding energy of 0.71 +/- 0.01 eV around K valley in the Brillouin zone.

  15. P-shell hyperon binding energies

    International Nuclear Information System (INIS)

    Koetsier, D.; Amos, K.

    1991-01-01

    A shell model for lambda hypernuclei has been used to determine the binding energy of the hyperon in nuclei throughout the p shell. Conventional (Cohen and Kurath) potential energies for nucleon-nucleon interactions were used with hyperon-nucleon interactions taken from Nijmegen one boson exchange potentials. The hyperon binding energies calculated from these potentials compare well with measured values. 7 refs., 2 figs

  16. Extracellular and intracellular steroid binding proteins

    International Nuclear Information System (INIS)

    Wagner, R.K.

    1978-01-01

    Steroid hormone binding proteins can be measured, after the removal of endogenous steroids, as specific complexes with radio-labelled hormones. In this study all the requirements for a quantitative determination of steroid hormone binding proteins are defined. For different methods, agargel electrophoresis, density gradient centrifugation, equilibrium dialysis and polyacrylamide electrophoresis have been evaluated. Agar electrophoresis at low temperature was found to be the simplest and most useful procedure. With this method the dissociation rates of high affinity complexes can be assessed and absolute binding protein concentrations can be determined. The dissociation rates of the oestradiol-oestrogen receptor complex and the R-5020-progestin receptor complex are low (1-2% per h run time.) In contrast, that of complexes between androgen receptor and dihydrotestosterone (17β-hydroxy-5α-androstan-3-one (DHT), progestin receptor and progesterone, corticosteroid binding globulin (CBG) and cortisol or progesterone and sex hormone binding globulin (SHBG) and DHT were hign (16-27% per h run time). Target tissue extracts (cytosols) contain, besides soluble tissue proteins, large amounts of plasma proteins. The extent of this plasma contamination can be determined by measuring the albumin concentration in cytosols by immunodiffusion. In cytosols of 4 different human target tissues the albumin content varied from 20-30% corresponding to an even higher whole plasma concentration. Steroid binding plasma proteins, such as CBG and SHBG are constituents of this containment. (author)

  17. The readiness potential reflects intentional binding

    Directory of Open Access Journals (Sweden)

    Han-Gue eJo

    2014-06-01

    Full Text Available When a voluntary action is causally linked with a sensory outcome, the action and its consequent effect are perceived as being closer together in time. This effect is called intentional binding. Although many experiments were conducted on this phenomenon, the underlying neural mechanisms are not well understood. While intentional binding is specific to voluntary action, we presumed that preconscious brain activity (the readiness potential, RP, which occurs before an action is made, might play an important role in this binding effect. In this study, the brain dynamics were recorded with electroencephalography (EEG and analyzed in single-trials in order to estimate whether intentional binding is correlated with the early neural processes. Moreover, we were interested in different behavioral performance between meditators and non-meditators since meditators are expected to be able to keep attention more consistently on a task. Thus, we performed the intentional binding paradigm with twenty mindfulness meditators and compared them to matched controls. Although, we did not observe a group effect on either behavioral data or EEG recordings, we found that self-initiated movements following ongoing negative deflections of slow cortical potentials (SCPs result in a stronger binding effect compared to positive potentials, especially regarding the perceived time of the consequent effect. Our results provide the first direct evidence that the early neural activity within the range of SCPs affects perceived time of a sensory outcome that is caused by intentional action.

  18. DNA-Aptamers Binding Aminoglycoside Antibiotics

    Directory of Open Access Journals (Sweden)

    Nadia Nikolaus

    2014-02-01

    Full Text Available Aptamers are short, single stranded DNA or RNA oligonucleotides that are able to bind specifically and with high affinity to their non-nucleic acid target molecules. This binding reaction enables their application as biorecognition elements in biosensors and assays. As antibiotic residues pose a problem contributing to the emergence of antibiotic-resistant pathogens and thereby reducing the effectiveness of the drug to fight human infections, we selected aptamers targeted against the aminoglycoside antibiotic kanamycin A with the aim of constructing a robust and functional assay that can be used for water analysis. With this work we show that aptamers that were derived from a Capture-SELEX procedure targeting against kanamycin A also display binding to related aminoglycoside antibiotics. The binding patterns differ among all tested aptamers so that there are highly substance specific aptamers and more group specific aptamers binding to a different variety of aminoglycoside antibiotics. Also the region of the aminoglycoside antibiotics responsible for aptamer binding can be estimated. Affinities of the different aptamers for their target substance, kanamycin A, are measured with different approaches and are in the micromolar range. Finally, the proof of principle of an assay for detection of kanamycin A in a real water sample is given.

  19. LIBRA: LIgand Binding site Recognition Application.

    Science.gov (United States)

    Hung, Le Viet; Caprari, Silvia; Bizai, Massimiliano; Toti, Daniele; Polticelli, Fabio

    2015-12-15

    In recent years, structural genomics and ab initio molecular modeling activities are leading to the availability of a large number of structural models of proteins whose biochemical function is not known. The aim of this study was the development of a novel software tool that, given a protein's structural model, predicts the presence and identity of active sites and/or ligand binding sites. The algorithm implemented by ligand binding site recognition application (LIBRA) is based on a graph theory approach to find the largest subset of similar residues between an input protein and a collection of known functional sites. The algorithm makes use of two predefined databases for active sites and ligand binding sites, respectively, derived from the Catalytic Site Atlas and the Protein Data Bank. Tests indicate that LIBRA is able to identify the correct binding/active site in 90% of the cases analyzed, 90% of which feature the identified site as ranking first. As far as ligand binding site recognition is concerned, LIBRA outperforms other structure-based ligand binding sites detection tools with which it has been compared. The application, developed in Java SE 7 with a Swing GUI embedding a JMol applet, can be run on any OS equipped with a suitable Java Virtual Machine (JVM), and is available at the following URL: http://www.computationalbiology.it/software/LIBRAv1.zip. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  20. Zinc Binding by Lactic Acid Bacteria

    Directory of Open Access Journals (Sweden)

    Jasna Mrvčić

    2009-01-01

    Full Text Available Zinc is an essential trace element in all organisms. A common method for the prevention of zinc deficiency is pharmacological supplementation, especially in a highly available form of a metalloprotein complex. The potential of different microbes to bind essential and toxic heavy metals has recently been recognized. In this work, biosorption of zinc by lactic acid bacteria (LAB has been investigated. Specific LAB were assessed for their ability to bind zinc from a water solution. Significant amount of zinc ions was bound, and this binding was found to be LAB species-specific. Differences among the species in binding performance at a concentration range between 10–90 mg/L were evaluated with Langmuir model for biosorption. Binding of zinc was a fast process, strongly influenced by ionic strength, pH, biomass concentration, and temperature. The most effective metal-binding LAB species was Leuconostoc mesenteroides (27.10 mg of Zn2+ per gram of dry mass bound at pH=5 and 32 °C, during 24 h. FT-IR spectroscopy analysis and electron microscopy demonstrated that passive adsorption and active uptake of the zinc ions were involved.

  1. Radiation damage to DNA-binding proteins

    International Nuclear Information System (INIS)

    Culard, G.; Eon, S.; DeVuyst, G.; Charlier, M.; Spotheim-Maurizot, M.

    2003-01-01

    The DNA-binding properties of proteins are strongly affected upon irradiation. The tetrameric lactose repressor (a dimer of dimers) losses its ability to bind operator DNA as soon as at least two damages per protomer of each dimer occur. The monomeric MC1 protein losses its ability to bind DNA in two steps : i) at low doses only the specific binding is abolished, whereas the non-specific one is still possible; ii) at high doses all binding vanishes. Moreover, the DNA bending induced by MC1 binding is less pronounced for a protein that underwent the low dose irradiation. When the entire DNA-protein complexes are irradiated, the observed disruption of the complexes is mainly due to the damage of the proteins and not to that of DNA. The doses necessary for complex disruption are higher than those inactivating the free protein. This difference, larger for MC1 than for lactose repressor, is due to the protection of the protein by the bound DNA. The oxidation of the protein side chains that are accessible to the radiation-induced hydroxyl radicals seems to represent the inactivating damage

  2. Mannose-Binding Lectin Binds to Amyloid Protein and Modulates Inflammation

    Directory of Open Access Journals (Sweden)

    Mykol Larvie

    2012-01-01

    Full Text Available Mannose-binding lectin (MBL, a soluble factor of the innate immune system, is a pattern recognition molecule with a number of known ligands, including viruses, bacteria, and molecules from abnormal self tissues. In addition to its role in immunity, MBL also functions in the maintenance of tissue homeostasis. We present evidence here that MBL binds to amyloid β peptides. MBL binding to other known carbohydrate ligands is calcium-dependent and has been attributed to the carbohydrate-recognition domain, a common feature of other C-type lectins. In contrast, we find that the features of MBL binding to Aβ are more similar to the reported binding characteristics of the cysteine-rich domain of the unrelated mannose receptor and therefore may involve the MBL cysteine-rich domain. Differences in MBL ligand binding may contribute to modulation of inflammatory response and may correlate with the function of MBL in processes such as coagulation and tissue homeostasis.

  3. Genetic variation in bone morphogenetic protein (BMP) and colon and rectal cancer

    Science.gov (United States)

    Slattery, Martha L.; Lundgreen, Abbie; Herrick, Jennifer S.; Kadlubar, Susan; Caan, Bette J.; Potter, John D.; Wolff, Roger K.

    2011-01-01

    Bone morphogenetic proteins (BMP) are part of the TGF-β-signaling pathway; genetic variation in these genes may be involved in colorectal cancer. In this study we evaluated the association between genetic variation in BMP1 (11 tagSNPs), BMP2 (5 tagSNPs), BMP4 (3 tagSNPs), BMPR1A (9 tagSNPs), BMPR1B (21 tagSNPs), BMPR2 (11 tagSNPs), and GDF10 (7 tagSNPs) with risk of colon and rectal cancer and tumor molecular phenotype. We used data from population-based case-control studies (colon cancer n=1574 cases, 1970 controls; rectal cancer n=791 cases, 999 controls). We observed that genetic variation in BMPR1A, BMPR1B, BMPR2, BMP2, and BMP4 was associated with risk of developing colon cancer, with 20 to 30% increased risk for most high-risk genotypes. A summary of high-risk genotypes showed over a twofold increase in colon cancer risk at the upper risk category (OR 2.49 95% CI 1.95, 3.18). BMPR2, BMPR1B, BMP2, and GDF10 were associated with rectal cancer. BMPR2 rs2228545 was associated with an almost twofold increased risk of rectal cancer. The risk associated with the highest category of the summary score for rectal cancer was 2.97 (95% CI 1.87, 4.72). Genes in the BMP-signaling pathway were consistently associated with CIMP+ status in combination with both KRAS-mutated and MSI tumors. BMP genes interacted statistically significantly with other genes in the TGF-β-signaling pathway, including TGFβ1, TGFβR1, Smad 3, Smad 4, and Smad 7. Our data support a role for genetic variation in BMP-related genes in the etiology of colon and rectal cancer. One possible mechanism is via the TGF-β-signaling pathway. PMID:21387313

  4. Recent improvements to Binding MOAD: a resource for protein–ligand binding affinities and structures

    Science.gov (United States)

    Ahmed, Aqeel; Smith, Richard D.; Clark, Jordan J.; Dunbar, James B.; Carlson, Heather A.

    2015-01-01

    For over 10 years, Binding MOAD (Mother of All Databases; http://www.BindingMOAD.org) has been one of the largest resources for high-quality protein–ligand complexes and associated binding affinity data. Binding MOAD has grown at the rate of 1994 complexes per year, on average. Currently, it contains 23 269 complexes and 8156 binding affinities. Our annual updates curate the data using a semi-automated literature search of the references cited within the PDB file, and we have recently upgraded our website and added new features and functionalities to better serve Binding MOAD users. In order to eliminate the legacy application server of the old platform and to accommodate new changes, the website has been completely rewritten in the LAMP (Linux, Apache, MySQL and PHP) environment. The improved user interface incorporates current third-party plugins for better visualization of protein and ligand molecules, and it provides features like sorting, filtering and filtered downloads. In addition to the field-based searching, Binding MOAD now can be searched by structural queries based on the ligand. In order to remove redundancy, Binding MOAD records are clustered in different families based on 90% sequence identity. The new Binding MOAD, with the upgraded platform, features and functionalities, is now equipped to better serve its users. PMID:25378330

  5. Recent improvements to Binding MOAD: a resource for protein-ligand binding affinities and structures.

    Science.gov (United States)

    Ahmed, Aqeel; Smith, Richard D; Clark, Jordan J; Dunbar, James B; Carlson, Heather A

    2015-01-01

    For over 10 years, Binding MOAD (Mother of All Databases; http://www.BindingMOAD.org) has been one of the largest resources for high-quality protein-ligand complexes and associated binding affinity data. Binding MOAD has grown at the rate of 1994 complexes per year, on average. Currently, it contains 23,269 complexes and 8156 binding affinities. Our annual updates curate the data using a semi-automated literature search of the references cited within the PDB file, and we have recently upgraded our website and added new features and functionalities to better serve Binding MOAD users. In order to eliminate the legacy application server of the old platform and to accommodate new changes, the website has been completely rewritten in the LAMP (Linux, Apache, MySQL and PHP) environment. The improved user interface incorporates current third-party plugins for better visualization of protein and ligand molecules, and it provides features like sorting, filtering and filtered downloads. In addition to the field-based searching, Binding MOAD now can be searched by structural queries based on the ligand. In order to remove redundancy, Binding MOAD records are clustered in different families based on 90% sequence identity. The new Binding MOAD, with the upgraded platform, features and functionalities, is now equipped to better serve its users. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  6. Crystal structure of the botulinum neurotoxin type G binding domain: insight into cell surface binding.

    Science.gov (United States)

    Stenmark, Pål; Dong, Min; Dupuy, Jérôme; Chapman, Edwin R; Stevens, Raymond C

    2010-04-16

    Botulinum neurotoxins (BoNTs) typically bind the neuronal cell surface via dual interactions with both protein receptors and gangliosides. We present here the 1.9-A X-ray structure of the BoNT serotype G (BoNT/G) receptor binding domain (residues 868-1297) and a detailed view of protein receptor and ganglioside binding regions. The ganglioside binding motif (SxWY) has a conserved structure compared to the corresponding regions in BoNT serotype A and BoNT serotype B (BoNT/B), but several features of interactions with the hydrophilic face of the ganglioside are absent at the opposite side of the motif in the BoNT/G ganglioside binding cleft. This may significantly reduce the affinity between BoNT/G and gangliosides. BoNT/G and BoNT/B share the protein receptor synaptotagmin (Syt) I/II. The Syt binding site has a conserved hydrophobic plateau located centrally in the proposed protein receptor binding interface (Tyr1189, Phe1202, Ala1204, Pro1205, and Phe1212). Interestingly, only 5 of 14 residues that are important for binding between Syt-II and BoNT/B are conserved in BoNT/G, suggesting that the means by which BoNT/G and BoNT/B bind Syt diverges more than previously appreciated. Indeed, substitution of Syt-II Phe47 and Phe55 with alanine residues had little effect on the binding of BoNT/G, but strongly reduced the binding of BoNT/B. Furthermore, an extended solvent-exposed hydrophobic loop, located between the Syt binding site and the ganglioside binding cleft, may serve as a third membrane association and binding element to contribute to high-affinity binding to the neuronal membrane. While BoNT/G and BoNT/B are homologous to each other and both utilize Syt-I/Syt-II as their protein receptor, the precise means by which these two toxin serotypes bind to Syt appears surprisingly divergent. Copyright (c) 2010. Published by Elsevier Ltd.

  7. Structure-function relationships of Na+, K+, ATP, or Mg2+ binding and energy transduction in Na,K-ATPase

    DEFF Research Database (Denmark)

    Jorgensen, Peter L.; Pedersen, Per Amstrup

    2000-01-01

    Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction......Na,K-ATPase; Mutagenesis; Na+ binding; K+ binding; Tl+ binding; Mg2+ binding; ATP binding; Cation binding site; Energy transduction...

  8. Alpine ski bindings and injuries. Current findings.

    Science.gov (United States)

    Natri, A; Beynnon, B D; Ettlinger, C F; Johnson, R J; Shealy, J E

    1999-07-01

    In spite of the fact that the overall incidence of alpine ski injuries has decreased during the last 25 years, the incidence of serious knee sprains usually involving the anterior cruciate ligament (ACL) has risen dramatically since the late 1970s. This trend runs counter to a dramatic reduction in lower leg injuries that began in the early 1970s and to date has lowered the risk of injury below the knee by almost 90%. One of the primary design objectives of modern ski boots and bindings has been to protect the skier from tibia and ankle fractures. So, in that sense, they have done an excellent job. However, despite advances in equipment design, modern ski bindings have not protected the knee from serious ligament trauma. At the present time, we are unaware of any binding design, settings or function that can protect both the knee and lower extremities from serious ligament sprains. No innovative change in binding design appears to be on the horizon that has the potential to reduce the risk of these severe knee injuries. Indeed, only 1 study has demonstrated a means to help reduce this risk of serious knee sprains, and this study involved education of skiers, not ski equipment. Despite the inability of bindings to reduce the risk of severe knee injuries there can be no doubt that improvement in ski bindings has been the most important factor in the marked reduction in incidence of lower leg and ankle injuries during the last 25 years. The authors strongly endorse the application of present International Standards Organisation (ISO) and American Society for Testing and Materials (ASTM) standards concerning mounting, setting and maintaining modern 'state of the art' bindings.

  9. Dissociation of binding and learning processes.

    Science.gov (United States)

    Moeller, Birte; Frings, Christian

    2017-11-01

    A single encounter of a stimulus together with a response can result in a short-lived association between the stimulus and the response [sometimes called an event file, see Hommel, Müsseler, Aschersleben, & Prinz, (2001) Behavioral and Brain Sciences, 24, 910-926]. The repetition of stimulus-response pairings typically results in longer lasting learning effects indicating stimulus-response associations (e.g., Logan & Etherton, (1994) Journal of Experimental Psychology: Learning, Memory, and Cognition, 20, 1022-1050]. An important question is whether or not what has been described as stimulus-response binding in action control research is actually identical with an early stage of incidental learning (e.g., binding might be seen as single-trial learning). Here, we present evidence that short-lived binding effects can be distinguished from learning of longer lasting stimulus-response associations. In two experiments, participants always responded to centrally presented target letters that were flanked by response irrelevant distractor letters. Experiment 1 varied whether distractors flanked targets on the horizontal or vertical axis. Binding effects were larger for a horizontal than for a vertical distractor-target configuration, while stimulus configuration did not influence incidental learning of longer lasting stimulus-response associations. In Experiment 2, the duration of the interval between response n - 1 and presentation of display n (500 ms vs. 2000 ms) had opposing influences on binding and learning effects. Both experiments indicate that modulating factors influence stimulus-response binding and incidental learning effects in different ways. We conclude that distinct underlying processes should be assumed for binding and incidental learning effects.

  10. CaMELS: In silico prediction of calmodulin binding proteins and their binding sites.

    Science.gov (United States)

    Abbasi, Wajid Arshad; Asif, Amina; Andleeb, Saiqa; Minhas, Fayyaz Ul Amir Afsar

    2017-09-01

    Due to Ca 2+ -dependent binding and the sequence diversity of Calmodulin (CaM) binding proteins, identifying CaM interactions and binding sites in the wet-lab is tedious and costly. Therefore, computational methods for this purpose are crucial to the design of such wet-lab experiments. We present an algorithm suite called CaMELS (CalModulin intEraction Learning System) for predicting proteins that interact with CaM as well as their binding sites using sequence information alone. CaMELS offers state of the art accuracy for both CaM interaction and binding site prediction and can aid biologists in studying CaM binding proteins. For CaM interaction prediction, CaMELS uses protein sequence features coupled with a large-margin classifier. CaMELS models the binding site prediction problem using multiple instance machine learning with a custom optimization algorithm which allows more effective learning over imprecisely annotated CaM-binding sites during training. CaMELS has been extensively benchmarked using a variety of data sets, mutagenic studies, proteome-wide Gene Ontology enrichment analyses and protein structures. Our experiments indicate that CaMELS outperforms simple motif-based search and other existing methods for interaction and binding site prediction. We have also found that the whole sequence of a protein, rather than just its binding site, is important for predicting its interaction with CaM. Using the machine learning model in CaMELS, we have identified important features of protein sequences for CaM interaction prediction as well as characteristic amino acid sub-sequences and their relative position for identifying CaM binding sites. Python code for training and evaluating CaMELS together with a webserver implementation is available at the URL: http://faculty.pieas.edu.pk/fayyaz/software.html#camels. © 2017 Wiley Periodicals, Inc.

  11. Protein Binding Capacity of Different Forages Tannin

    Science.gov (United States)

    Yusiati, L. M.; Kurniawati, A.; Hanim, C.; Anas, M. A.

    2018-02-01

    Eight forages of tannin sources(Leucaena leucocephala, Arachis hypogaea, Mimosa pudica, Morus alba L, Swietenia mahagoni, Manihot esculenta, Gliricidia sepium, and Bauhinia purpurea)were evaluated their tannin content and protein binding capacity. The protein binding capacity of tannin were determined using precipitation of bovine serum albumin (BSA). Swietenia mahagonihas higest total tannin level and condensed tannin (CT) compared with other forages (P<0.01). The Leucaena leucocephala has highest hydrolysable tannin (HT) level (P<0.01). The total and condensed tannin content of Swietenia mahagoni were 11.928±0.04 mg/100 mg and 9.241±0.02mg/100mg dry matter (DM) of leaves. The hydrolysable tannin content of Leucaena leucocephala was 5.338±0.03 mg/100 mg DM of leaves. Binding capacity was highest in Swietenia mahagoni and Leucaena leucocephala compared to the other forages (P<0.01). The optimum binding of BSA to tannin in Leucaena leucocephala and Swietenia mahagoniwere1.181±0.44 and 1.217±0.60mg/mg dry matter of leaves. The present study reports that Swietenia mahagoni has highest of tannin content and Leucaena leucocephala and Swietenia mahagoni capacity of protein binding.

  12. Adjustment of legally binding local plans

    DEFF Research Database (Denmark)

    Hvingel, Line Træholt; Aunsborg, Christian; Christensen, Finn Kjær

    2012-01-01

    Traditionally, and by law, new urban areas in Denmark are regulated and planned through legally binding local plans. Recently a tendency has occurred: The municipalities make the legally binding local plans quite open for future adjustment, and they are using a substantial amount of ‘empowerment ...... the considerations of legal rights, the extend of the legal use of empowerment provisions and the combination of the use of legal binding local plans and other legal instruments such as easements and sales agreements.......Traditionally, and by law, new urban areas in Denmark are regulated and planned through legally binding local plans. Recently a tendency has occurred: The municipalities make the legally binding local plans quite open for future adjustment, and they are using a substantial amount of ‘empowerment...... provisions’ which empower the municipalities to later ruling. This way of making plans postpones the actual regulation of an area (i.e. the planning permission) making it an individual ruling for instance at the application of building permits. Case studies show examples of this way of regulating an area...

  13. Assessment of the binding properties of granuloszint

    International Nuclear Information System (INIS)

    Schubiger, P.A.; Hasler, P.H.; Novak-Hofer, I.; Blaeuenstein, P.

    1989-01-01

    123 I-granuloszint (a murine monoclonal antibody - called AK-47 - against NCA-95 glycoprotein of granulocytes) has been proved to be a very convenient and successful radiopharmaceutical for visualizing infectious diseases. For a broad introduction in routine nuclear medicine it was necessary to optimize the labelling method and to determine in vitro exactly those biological and binding parameters which are relevant for an effective application in vivo. Binding to granulocytes has been shown to be specific and saturable (nonspecific binding about 10%) and is not via the Fc part of the antibody. The investigation of the binding properties of 125 I-labelled AK-47 gave the following results: Affinity constant 5x10 8 , 20,000-100,000 epitopes per granulocyte and an immunoreactivity of more than 90%. Labelling with 123 I reduced the immunoreactivity to 40%. The Lindmo method and immunoblotting are used as quality control to check the likely in vivo behaviour of the labelled antibody. There is a good correspondence between the results from the two methods. With our special labelling method and the different in vitro checks we have found a reliable way to control the production and to assure an optimal binding behaviour of 123 I-granuloszint. (orig.)

  14. Assessment of the binding properties of granuloszint

    Energy Technology Data Exchange (ETDEWEB)

    Schubiger, P.A.; Hasler, P.H.; Novak-Hofer, I.; Blaeuenstein, P.

    1989-09-01

    /sup 123/I-granuloszint (a murine monoclonal antibody - called AK-47 - against NCA-95 glycoprotein of granulocytes) has been proved to be a very convenient and successful radiopharmaceutical for visualizing infectious diseases. For a broad introduction in routine nuclear medicine it was necessary to optimize the labelling method and to determine in vitro exactly those biological and binding parameters which are relevant for an effective application in vivo. Binding to granulocytes has been shown to be specific and saturable (nonspecific binding about 10%) and is not via the Fc part of the antibody. The investigation of the binding properties of /sup 125/I-labelled AK-47 gave the following results: Affinity constant 5x10/sup 8/, 20,000-100,000 epitopes per granulocyte and an immunoreactivity of more than 90%. Labelling with /sup 123/I reduced the immunoreactivity to 40%. The Lindmo method and immunoblotting are used as quality control to check the likely in vivo behaviour of the labelled antibody. There is a good correspondence between the results from the two methods. With our special labelling method and the different in vitro checks we have found a reliable way to control the production and to assure an optimal binding behaviour of /sup 123/I-granuloszint. (orig.).

  15. New Mechanisms of Mercury Binding to Peat

    Science.gov (United States)

    Nagy, K. L.; Manceau, A.; Gasper, J. D.; Ryan, J. N.; Aiken, G. R.

    2007-12-01

    Mercury can be immobilized in the aquatic environment by binding to peat, a solid form of natural organic matter. Binding mechanisms can vary in strength and reversibility, and therefore will control concentrations of bioreactive mercury, may explain rates of mercury methylation, and are important for designing approaches to improve water quality using natural wetlands or engineered phytoremediation schemes. In addition, strong binding between mercury and peat is likely to result in the fixation of mercury that ultimately resides in coal. The mechanisms by which aqueous mercury at low concentrations reacts with both dissolved and solid natural organic matter remain incompletely understood, despite recent efforts. We have identified three distinct binding mechanisms of divalent cationic mercury to solid peats from the Florida Everglades using EXAFS spectroscopic data (FAME beamline, European Synchrotron Radiation Facility (ESRF)) obtained on experimental samples as compared to relevant references including mercury-bearing solids and mercury bound to various organic molecules. The proportions of the three molecular configurations vary with Hg concentration, and two new configurations that involve sulfur ligands occur at Hg concentrations up to about 4000 ppm. The binding mechanism at the lowest experimental Hg concentration (60-80 ppm) elucidates published reports on the inhibition of metacinnabar formation in the presence of Hg-bearing solutions and dissolved natural organic matter, and also, the differences in extent of mercury methylation in distinct areas of the Florida Everglades.

  16. Endocytosis of Integrin-Binding Human Picornaviruses

    Directory of Open Access Journals (Sweden)

    Pirjo Merilahti

    2012-01-01

    Full Text Available Picornaviruses that infect humans form one of the largest virus groups with almost three hundred virus types. They include significant enteroviral pathogens such as rhino-, polio-, echo-, and coxsackieviruses and human parechoviruses that cause wide range of disease symptoms. Despite the economic importance of picornaviruses, there are no antivirals. More than ten cellular receptors are known to participate in picornavirus infection, but experimental evidence of their role in cellular infection has been shown for only about twenty picornavirus types. Three enterovirus types and one parechovirus have experimentally been shown to bind and use integrin receptors in cellular infection. These include coxsackievirus A9 (CV-A9, echovirus 9, and human parechovirus 1 that are among the most common and epidemic human picornaviruses and bind to αV-integrins via RGD motif that resides on virus capsid. In contrast, echovirus 1 (E-1 has no RGD and uses integrin α2β1 as cellular receptor. Endocytosis of CV-A9 has recently been shown to occur via a novel Arf6- and dynamin-dependent pathways, while, contrary to collagen binding, E-1 binds inactive β1 integrin and enters via macropinocytosis. In this paper, we review what is known about receptors and endocytosis of integrin-binding human picornaviruses.

  17. Human serum albumin binding of certain antimalarials

    Science.gov (United States)

    Marković, Olivera S.; Cvijetić, Ilija N.; Zlatović, Mario V.; Opsenica, Igor M.; Konstantinović, Jelena M.; Terzić Jovanović, Nataša V.; Šolaja, Bogdan A.; Verbić, Tatjana Ž.

    2018-03-01

    Interactions between eight in-house synthesized aminoquinolines, along with well-known chloroquine, and human serum albumin (HSA) have been studied by fluorescence spectroscopy. The synthesized aminoquinolines, despite being structurally diverse, were found to be very potent antimalarials. Fluorescence measurements indicate that three compounds having additional thiophene or benzothiophene substructure bind more strongly to HSA than other studied compounds. Competitive binding experiments indicate that these three compounds bind significantly stronger to warfarin compared to diazepam binding site. Fluorescence quenching at three temperatures (20, 25, and 37 °C) was analyzed using classical Stern-Volmer equation, and a static quenching mechanism was proposed. The enthalpy and entropy changes upon sulphur-containing compound-HSA interactions were calculated using Van't Hoff equation. Positive values of enthalpy and entropy changes indicate that non-specific, hydrophobic interactions are the main contributors to HSA-compound interaction. Molecular docking and calculated lipophilicity descriptors indicate the same, pointing out that the increased lipophilicity of sulphur-containing compounds might be a reason for their better binding to HSA. Obtained results might contribute to design of novel derivatives with improved pharmacokinetic properties and drug efficacy.

  18. Binding of anandamide to bovine serum albumin

    DEFF Research Database (Denmark)

    Bojesen, I.N.; Hansen, Harald S.

    2003-01-01

    The endocannabinoid anandamide is of lipid nature and may thus bind to albumin in the vascular system, as do fatty acids. The knowledge of the free water-phase concentration of anandamide is essential for the investigations of its transfer from the binding protein to cellular membranes, because...... a water-phase shuttle of monomers mediates such transfers. We have used our method based upon the use of albumin-filled red cell ghosts as a dispersed biological "reference binder" to measure the water-phase concentrations of anandamide. These concentrations were measured in buffer (pH 7.3) in equilibrium...... that BSA has one high-affinity binding site for anandamide at all four temperatures. The free energy of anandamide binding (¿G) is calculated to -43.05 kJ mol with a large enthalpy (¿H ) contribution of -42.09 kJ mol. Anandamide has vasodilator activity, and the binding to albumin may mediate its transport...

  19. Binding of Fidarestat Stereoisomers with Aldose Reductase

    Directory of Open Access Journals (Sweden)

    Dae-Sil Lee

    2006-11-01

    Full Text Available The stereospecificity in binding to aldose reductase (ALR2 of two fidarestat {6-fluoro-2',5'-dioxospiro[chroman-4,4'-imidazolidine]-2-carboxamide} stereoisomers [(2S,4Sand (2R,4S] has been investigated by means of molecular dynamics simulations using freeenergy integration techniques. The difference in the free energy of binding was found to be2.0 ± 1.7 kJ/mol in favour of the (2S,4S-form, in agreement with the experimentalinhibition data. The relative mobilities of the fidarestats complexed with ALR2 indicate alarger entropic penalty for hydrophobic binding of (2R,4S-fidarestat compared to (2S,4S-fidarestat, partially explaining its lower binding affinity. The two stereoisomers differmainly in the orientation of the carbamoyl moiety with respect to the active site and rotationof the bond joining the carbamoyl substituent to the ring. The detailed structural andenergetic insights obtained from out simulations allow for a better understanding of thefactors determining stereospecific inhibitor-ALR2 binding in the EPF charges model.

  20. DNA binding studies of tartrazine food additive.

    Science.gov (United States)

    Kashanian, Soheila; Zeidali, Sahar Heidary

    2011-07-01

    The interaction of native calf thymus DNA with tartrazine in 10 mM Tris-HCl aqueous solution at neutral pH 7.4 was investigated. Tartrazine is a nitrous derivative and may cause allergic reactions, with a potential of toxicological risk. Also, tartrazine induces oxidative stress and DNA damage. Its DNA binding properties were studied by UV-vis and circular dichroism spectra, competitive binding with Hoechst 33258, and viscosity measurements. Tartrazine molecules bind to DNA via groove mode as illustrated by hyperchromism in the UV absorption band of tartrazine, decrease in Hoechst-DNA solution fluorescence, unchanged viscosity of DNA, and conformational changes such as conversion from B-like to C-like in the circular dichroism spectra of DNA. The binding constants (K(b)) of DNA with tartrazine were calculated at different temperatures. Enthalpy and entropy changes were calculated to be +37 and +213 kJ mol(-1), respectively, according to the Van't Hoff equation, which indicated that the reaction is predominantly entropically driven. Also, tartrazine does not cleave plasmid DNA. Tartrazine interacts with calf thymus DNA via a groove interaction mode with an intrinsic binding constant of 3.75 × 10(4) M(-1).

  1. Binding of ethidium to the nucleosome core particle. 2. Internal and external binding modes

    International Nuclear Information System (INIS)

    McMurray, C.T.; Small, E.W.; van Holde, K.E.

    1991-01-01

    The authors have previously reported that the binding of ethidium bromide to the nucleosome core particle results in a stepwise dissociation of the structure which involves the initial release of one copy each of H2A and H2B. In this report, they have examined the absorbance and fluorescence properties of intercalated and outside bound forms of ethidium bromide. From these properties, they have measured the extent of external, electrostatic binding of the dye versus internal, intercalation binding to the core particle, free from contribution by linker DNA. They have established that dissociation is induced by the intercalation mode of binding to DNA within the core particle DNA, and not by binding to the histones or by nonintercalative binding to DNA. The covalent binding of [ 3 H]-8-azidoethidium to the core particle clearly shows that < 1.0 adduct is formed per histone octamer over a wide range of input ratios. Simultaneously, analyses of steady-state fluorescence enhancement and fluorescence lifetime data from bound ethidium complexes demonstrate extensive intercalation binding. Combined analyses from steady-state fluorescence intensity with equilibrium dialysis or fluorescence lifetime data revealed that dissociation began when ∼14 ethidium molecules are bound by intercalation to each core particle and < 1.0 nonintercalated ion pair was formed per core particle

  2. The interrelationship between ligand binding and self-association of the folate binding protein

    DEFF Research Database (Denmark)

    Holm, Jan; Schou, Christian; Babol, Linnea N.

    2011-01-01

    The folate binding protein (FBP) regulates homeostasis and intracellular trafficking of folic acid, a vitamin of decisive importance in cell division and growth. We analyzed whether interrelationship between ligand binding and self-association of FBP plays a significant role in the physiology of ...

  3. Quantification of Cooperativity in Heterodimer-DNA Binding Improves the Accuracy of Binding Specificity Models*

    Science.gov (United States)

    Isakova, Alina; Berset, Yves; Hatzimanikatis, Vassily; Deplancke, Bart

    2016-01-01

    Many transcription factors (TFs) have the ability to cooperate on DNA elements as heterodimers. Despite the significance of TF heterodimerization for gene regulation, a quantitative understanding of cooperativity between various TF dimer partners and its impact on heterodimer DNA binding specificity models is still lacking. Here, we used a novel integrative approach, combining microfluidics-steered measurements of dimer-DNA assembly with mechanistic modeling of the implicated protein-protein-DNA interactions to quantitatively interrogate the cooperative DNA binding behavior of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ):retinoid X receptor α (RXRα) heterodimer. Using the high throughput MITOMI (mechanically induced trapping of molecular interactions) platform, we derived equilibrium DNA binding data for PPARγ, RXRα, as well as the PPARγ:RXRα heterodimer to more than 300 target DNA sites and variants thereof. We then quantified cooperativity underlying heterodimer-DNA binding and derived an integrative heterodimer DNA binding constant. Using this cooperativity-inclusive constant, we were able to build a heterodimer-DNA binding specificity model that has superior predictive power than the one based on a regular one-site equilibrium. Our data further revealed that individual nucleotide substitutions within the target site affect the extent of cooperativity in PPARγ:RXRα-DNA binding. Our study therefore emphasizes the importance of assessing cooperativity when generating DNA binding specificity models for heterodimers. PMID:26912662

  4. Quantification of Cooperativity in Heterodimer-DNA Binding Improves the Accuracy of Binding Specificity Models.

    Science.gov (United States)

    Isakova, Alina; Berset, Yves; Hatzimanikatis, Vassily; Deplancke, Bart

    2016-05-06

    Many transcription factors (TFs) have the ability to cooperate on DNA elements as heterodimers. Despite the significance of TF heterodimerization for gene regulation, a quantitative understanding of cooperativity between various TF dimer partners and its impact on heterodimer DNA binding specificity models is still lacking. Here, we used a novel integrative approach, combining microfluidics-steered measurements of dimer-DNA assembly with mechanistic modeling of the implicated protein-protein-DNA interactions to quantitatively interrogate the cooperative DNA binding behavior of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ):retinoid X receptor α (RXRα) heterodimer. Using the high throughput MITOMI (mechanically induced trapping of molecular interactions) platform, we derived equilibrium DNA binding data for PPARγ, RXRα, as well as the PPARγ:RXRα heterodimer to more than 300 target DNA sites and variants thereof. We then quantified cooperativity underlying heterodimer-DNA binding and derived an integrative heterodimer DNA binding constant. Using this cooperativity-inclusive constant, we were able to build a heterodimer-DNA binding specificity model that has superior predictive power than the one based on a regular one-site equilibrium. Our data further revealed that individual nucleotide substitutions within the target site affect the extent of cooperativity in PPARγ:RXRα-DNA binding. Our study therefore emphasizes the importance of assessing cooperativity when generating DNA binding specificity models for heterodimers. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Opioid binding sites in the guinea pig and rat kidney: Radioligand homogenate binding and autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Dissanayake, V.U.; Hughes, J.; Hunter, J.C. (Parke-Davis Research Unit, Addenbrookes Hospital Site, Cambridge (England))

    1991-07-01

    The specific binding of the selective {mu}-, {delta}-, and {kappa}-opioid ligands (3H)(D-Ala2,MePhe4,Gly-ol5)enkephalin ((3H) DAGOL), (3H)(D-Pen2,D-Pen5)enkephalin ((3H)DPDPE), and (3H)U69593, respectively, to crude membranes of the guinea pig and rat whole kidney, kidney cortex, and kidney medulla was investigated. In addition, the distribution of specific 3H-opioid binding sites in the guinea pig and rat kidney was visualized by autoradiography. Homogenate binding and autoradiography demonstrated the absence of {mu}- and {kappa}-opioid binding sites in the guinea pig kidney. No opioid binding sites were demonstrable in the rat kidney. In the guinea pig whole kidney, cortex, and medulla, saturation studies demonstrated that (3H)DPDPE bound with high affinity (KD = 2.6-3.5 nM) to an apparently homogeneous population of binding sites (Bmax = 8.4-30 fmol/mg of protein). Competition studies using several opioid compounds confirmed the nature of the {delta}-opioid binding site. Autoradiography experiments demonstrated that specific (3H)DPDPE binding sites were distributed radially in regions of the inner and outer medulla and at the corticomedullary junction of the guinea pig kidney. Computer-assisted image analysis of saturation data yielded KD values (4.5-5.0 nM) that were in good agreement with those obtained from the homogenate binding studies. Further investigation of the {delta}-opioid binding site in medulla homogenates, using agonist ((3H)DPDPE) and antagonist ((3H)diprenorphine) binding in the presence of Na+, Mg2+, and nucleotides, suggested that the {delta}-opioid site is linked to a second messenger system via a GTP-binding protein. Further studies are required to establish the precise localization of the {delta} binding site in the guinea pig kidney and to determine the nature of the second messenger linked to the GTP-binding protein in the medulla.

  6. Binding of alkylpyridinium chloride surfactants to sodium polystyrene sulfonate

    NARCIS (Netherlands)

    Ishiguro, M.; Koopal, L.K.

    2009-01-01

    Binding of cationic surfactants to anionic polymers is well studied. However, the surfactant binding characteristics at very low concentration near the start of binding and at high concentration, where charge compensation may Occur. are less well known. Therefore, the binding characteristics of

  7. Presence of a highly efficient binding to bacterial contamination can distort data from binding studies

    International Nuclear Information System (INIS)

    Balcar, V.J.

    1990-01-01

    3 HGABA at low concentrations (5-10 nM) was bound by what appeared to be a GABA receptor binding site in bacterial contamination originating from a batch of distilled water. Under experimental conditions similar to those usually employed in 3 HGABA binding studies, the apparent binding displayed a very high specific component and a high efficiency in terms of 3 HGABA bound per mg of protein. The binding was blocked by muscimol but not by isoguvacine, SR95531 and nipecotic acid. These characteristics suggest that the presence of such spurious binding in the experiments using 3H-labeled ligands in brain homogenates may not always be very obvious and, moreover, it can result in subtle, but serious, distortions of data from such studies, which may not be immediately recognized

  8. Receptor binding studies of the living heart

    International Nuclear Information System (INIS)

    Syrota, A.

    1988-01-01

    Receptors form a class of intrinsic membrane proteins (or glycoproteins) defined by the high affinity and specificity with which they bind ligands. Many receptors are associated directly or indirectly with membrane ion channels that open or close after a conformational change of the receptor induced by the binding of the neurotransmitter. Changes in number and/or affinity of cardiac neurotransmitter receptors have been associated with myocardial ischemia and infarction, congestive heart failure, and cardiomyopathy as well as diabetes or thyroid-induced heart muscle disease. These alterations of cardiac receptors have been demonstrated in vitro on membrane homogenates from samples collected mainly during surgery or postmortem. The disadvantage of these in vitro binding techniques is that receptors lose their natural environment and their relationships with the other components of the tissue

  9. The binding of Np to rat bone

    International Nuclear Information System (INIS)

    Ramounet, B.; Taylor, D.M.

    1997-01-01

    Neptunium has been shown to massively deposit in bone, after intravenous or intramuscular injections. Initially, it was uniformly distributed on periosteal and endosteal bone surfaces. The nature of the binding molecules, for this actinide, in the skeleton, has not yet been identified. The aim of this work was to characterize the ligands of neptunium by selective extractions of bone components. The preliminary results displayed the binding of 237 Np(IV) in the organic phase of bone, after intravenous or intramuscular contamination. Further studies are in progress, to quantify the fraction of Np bound to the organic and mineral compartment of bone, and to determine the affinity constant and the turn-over of the binding proteins. (authors)

  10. Dendrimers bind antioxidant polyphenols and cisplatin drug.

    Directory of Open Access Journals (Sweden)

    Amine Abderrezak

    Full Text Available Synthetic polymers of a specific shape and size play major role in drug delivery systems. Dendrimers are unique synthetic macromolecules of nanometer dimensions with a highly branched structure and globular shape with potential applications in gene and drug delivery. We examine the interaction of several dendrimers of different compositions mPEG-PAMAM (G3, mPEG-PAMAM (G4 and PAMAM (G4 with hydrophilic and hydrophobic drugs cisplatin, resveratrol, genistein and curcumin at physiological conditions. FTIR and UV-visible spectroscopic methods as well as molecular modeling were used to analyse drug binding mode, the binding constant and the effects of drug complexation on dendrimer stability and conformation. Structural analysis showed that cisplatin binds dendrimers in hydrophilic mode via Pt cation and polymer terminal NH(2 groups, while curcumin, genistein and resveratrol are located mainly in the cavities binding through both hydrophobic and hydrophilic contacts. The overall binding constants of durg-dendrimers are ranging from 10(2 M(-1 to 10(3 M(-1. The affinity of dendrimer binding was PAMAM-G4>mPEG-PAMAM-G4>mPEG-PAMAM-G3, while the order of drug-polymer stability was curcumin>cisplatin>genistein>resveratrol. Molecular modeling showed larger stability for genisten-PAMAM-G4 (ΔG = -4.75 kcal/mol than curcumin-PAMAM-G4 ((ΔG = -4.53 kcal/mol and resveratrol-PAMAM-G4 ((ΔG = -4.39 kcal/mol. Dendrimers might act as carriers to transport hydrophobic and hydrophilic drugs.

  11. Salt modulates the stability and lipid binding affinity of the adipocyte lipid-binding proteins

    Science.gov (United States)

    Schoeffler, Allyn J.; Ruiz, Carmen R.; Joubert, Allison M.; Yang, Xuemei; LiCata, Vince J.

    2003-01-01

    Adipocyte lipid-binding protein (ALBP or aP2) is an intracellular fatty acid-binding protein that is found in adipocytes and macrophages and binds a large variety of intracellular lipids with high affinity. Although intracellular lipids are frequently charged, biochemical studies of lipid-binding proteins and their interactions often focus most heavily on the hydrophobic aspects of these proteins and their interactions. In this study, we have characterized the effects of KCl on the stability and lipid binding properties of ALBP. We find that added salt dramatically stabilizes ALBP, increasing its Delta G of unfolding by 3-5 kcal/mol. At 37 degrees C salt can more than double the stability of the protein. At the same time, salt inhibits the binding of the fluorescent lipid 1-anilinonaphthalene-8-sulfonate (ANS) to the protein and induces direct displacement of the lipid from the protein. Thermodynamic linkage analysis of the salt inhibition of ANS binding shows a nearly 1:1 reciprocal linkage: i.e. one ion is released from ALBP when ANS binds, and vice versa. Kinetic experiments show that salt reduces the rate of association between ANS and ALBP while simultaneously increasing the dissociation rate of ANS from the protein. We depict and discuss the thermodynamic linkages among stability, lipid binding, and salt effects for ALBP, including the use of these linkages to calculate the affinity of ANS for the denatured state of ALBP and its dependence on salt concentration. We also discuss the potential molecular origins and potential intracellular consequences of the demonstrated salt linkages to stability and lipid binding in ALBP.

  12. Binding energy of two-dimensional biexcitons

    DEFF Research Database (Denmark)

    Singh, Jai; Birkedal, Dan; Vadim, Lyssenko

    1996-01-01

    Using a model structure for a two-dimensional (2D) biexciton confined in a quantum well, it is shown that the form of the Hamiltonian of the 2D biexciton reduces into that of an exciton. The binding energies and Bohr radii of a 2D biexciton in its various internal energy states are derived...... analytically using the fractional dimension approach. The ratio of the binding energy of a 2D biexciton to that of a 2D exciton is found to be 0.228, which agrees very well with the recent experimental value. The results of our approach are compared with those of earlier theories....

  13. Binding energies of hypernuclei and hypernuclear interactions

    Energy Technology Data Exchange (ETDEWEB)

    Bodmer, A.R. [Argonne National Lab., IL (United States)]|[Univ. of Illinois, Chicago, IL (United States). Dept. of Physics; Murali, S.; Usmani, Q.N. [Jamia Millia Islamia, New Delhi (India). Dept. of Physics

    1996-05-01

    In part 1 the effect of nuclear core dynamics on the binding energies of {Lambda} hypernuclei is discussed in the framework of variational correlated wave functions. In particular, the authors discuss a new rearrangement energy contribution and its effect on the core polarization. In part 2 they consider the interpretation of the {Lambda} single-particle energy in terms of basic {Lambda}-nuclear interactions using a local density approximation based on a Fermi hypernetted chain calculation of the A binding to nuclear matter. To account for the data strongly repulsive 3-body {Lambda}NN forces are required. Also in this framework they discuss core polarization for medium and heavier hypernuclei.

  14. Binding energies of hypernuclei and hypernuclear interactions

    International Nuclear Information System (INIS)

    Bodmer, A.R.; Univ. of Illinois, Chicago, IL; Murali, S.; Usmani, Q.N.

    1996-01-01

    In part 1 the effect of nuclear core dynamics on the binding energies of Λ hypernuclei is discussed in the framework of variational correlated wave functions. In particular, the authors discuss a new rearrangement energy contribution and its effect on the core polarization. In part 2 they consider the interpretation of the Λ single-particle energy in terms of basic Λ-nuclear interactions using a local density approximation based on a Fermi hypernetted chain calculation of the A binding to nuclear matter. To account for the data strongly repulsive 3-body ΛNN forces are required. Also in this framework they discuss core polarization for medium and heavier hypernuclei

  15. Studies on folate binding and a radioassay for serum and whole blood folate using goat milk as binding agent

    International Nuclear Information System (INIS)

    Piyasena, R.D.; Weerasekera, D.A.; Hettiaratchi, N.; Wikramanayake, T.W.; Sri Lanka Univ., Peradeniya Campus. Nuclear Medicine Unit)

    1977-01-01

    Preparations of cow, goat, buffalo, and human milk in addition to pig plasma were tested for folate binding properties. Of these, only pig plasma and goat milk showed sufficient binding to enable use as binding agents in a radioassay for serum and whole blood folate. The binding of folate by cow mild preparations in particular was found to be very poor. (orig.) [de

  16. Combined Effects of Vascular Endothelial Growth Factor and Bone Morphogenetic Protein 2 on Odonto/Osteogenic Differentiation of Human Dental Pulp Stem Cells In Vitro.

    Science.gov (United States)

    Aksel, Hacer; Huang, George T-J

    2017-06-01

    The purpose of this study was to investigate whether combined and concerted delivery of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2) enhances odonto/osteogenic differentiation of human dental pulp stem cells (DPSCs) in vitro. Various concentrations of VEGF and/or BMP-2 with or without the presence of odonto/osteogenic medium (OM) were added into DPSC cultures for 21 days. The mineral formation in cultures was evaluated using alizarin red stain (ARS). Optimal concentrations of VEGF and BMP-2 were codelivered to DPSCs for total of 21 days with the following experimental groups: (1) group 1: OM only, (2) group 2: OM + VEGF, (3) group 3: OM + BMP-2, and (4) group 4: OM + VEGF + BMP-2 (subgroup 4a: VEGF present the first 7 days, 4b: BMP-2 present the last 14 days, and 4c, both present for 21 days). Cultures were then subjected to quantitative ARS analysis or harvested for quantitative polymerase chain reaction analysis for the expression of core-binding factor alpha 1 (CBFA1), alkaline phosphatase (ALP), and dentin matrix protein 1 (DMP-1). No mineral formation was detected by ARS when VEGF and/or BMP-2 were used without OM. OM + VEGF, but not OM + BMP-2, formed more mineralization than OM (P  .05) in the expression of the 3 genes. VEGF addition in the early phase rather than a continuous presence of both VEGF and BMP-2 enhances odonto/osteogenic differentiation of DPSCs. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. Characterizing low affinity epibatidine binding to α4β2 nicotinic acetylcholine receptors with ligand depletion and nonspecific binding

    Science.gov (United States)

    2011-01-01

    Background Along with high affinity binding of epibatidine (Kd1≈10 pM) to α4β2 nicotinic acetylcholine receptor (nAChR), low affinity binding of epibatidine (Kd2≈1-10 nM) to an independent binding site has been reported. Studying this low affinity binding is important because it might contribute understanding about the structure and synthesis of α4β2 nAChR. The binding behavior of epibatidine and α4β2 AChR raises a question about interpreting binding data from two independent sites with ligand depletion and nonspecific binding, both of which can affect equilibrium binding of [3H]epibatidine and α4β2 nAChR. If modeled incorrectly, ligand depletion and nonspecific binding lead to inaccurate estimates of binding constants. Fitting total equilibrium binding as a function of total ligand accurately characterizes a single site with ligand depletion and nonspecific binding. The goal of this study was to determine whether this approach is sufficient with two independent high and low affinity sites. Results Computer simulations of binding revealed complexities beyond fitting total binding for characterizing the second, low affinity site of α4β2 nAChR. First, distinguishing low-affinity specific binding from nonspecific binding was a potential problem with saturation data. Varying the maximum concentration of [3H]epibatidine, simultaneously fitting independently measured nonspecific binding, and varying α4β2 nAChR concentration were effective remedies. Second, ligand depletion helped identify the low affinity site when nonspecific binding was significant in saturation or competition data, contrary to a common belief that ligand depletion always is detrimental. Third, measuring nonspecific binding without α4β2 nAChR distinguished better between nonspecific binding and low-affinity specific binding under some circumstances of competitive binding than did presuming nonspecific binding to be residual [3H]epibatidine binding after adding a large concentration of

  18. Characterizing low affinity epibatidine binding to α4β2 nicotinic acetylcholine receptors with ligand depletion and nonspecific binding

    Directory of Open Access Journals (Sweden)

    Person Alexandra M

    2011-11-01

    Full Text Available Abstract Background Along with high affinity binding of epibatidine (Kd1≈10 pM to α4β2 nicotinic acetylcholine receptor (nAChR, low affinity binding of epibatidine (Kd2≈1-10 nM to an independent binding site has been reported. Studying this low affinity binding is important because it might contribute understanding about the structure and synthesis of α4β2 nAChR. The binding behavior of epibatidine and α4β2 AChR raises a question about interpreting binding data from two independent sites with ligand depletion and nonspecific binding, both of which can affect equilibrium binding of [3H]epibatidine and α4β2 nAChR. If modeled incorrectly, ligand depletion and nonspecific binding lead to inaccurate estimates of binding constants. Fitting total equilibrium binding as a function of total ligand accurately characterizes a single site with ligand depletion and nonspecific binding. The goal of this study was to determine whether this approach is sufficient with two independent high and low affinity sites. Results Computer simulations of binding revealed complexities beyond fitting total binding for characterizing the second, low affinity site of α4β2 nAChR. First, distinguishing low-affinity specific binding from nonspecific binding was a potential problem with saturation data. Varying the maximum concentration of [3H]epibatidine, simultaneously fitting independently measured nonspecific binding, and varying α4β2 nAChR concentration were effective remedies. Second, ligand depletion helped identify the low affinity site when nonspecific binding was significant in saturation or competition data, contrary to a common belief that ligand depletion always is detrimental. Third, measuring nonspecific binding without α4β2 nAChR distinguished better between nonspecific binding and low-affinity specific binding under some circumstances of competitive binding than did presuming nonspecific binding to be residual [3H]epibatidine binding after

  19. RBPmap: a web server for mapping binding sites of RNA-binding proteins.

    Science.gov (United States)

    Paz, Inbal; Kosti, Idit; Ares, Manuel; Cline, Melissa; Mandel-Gutfreund, Yael

    2014-07-01

    Regulation of gene expression is executed in many cases by RNA-binding proteins (RBPs) that bind to mRNAs as well as to non-coding RNAs. RBPs recognize their RNA target via specific binding sites on the RNA. Predicting the binding sites of RBPs is known to be a major challenge. We present a new webserver, RBPmap, freely accessible through the website http://rbpmap.technion.ac.il/ for accurate prediction and mapping of RBP binding sites. RBPmap has been developed specifically for mapping RBPs in human, mouse and Drosophila melanogaster genomes, though it supports other organisms too. RBPmap enables the users to select motifs from a large database of experimentally defined motifs. In addition, users can provide any motif of interest, given as either a consensus or a PSSM. The algorithm for mapping the motifs is based on a Weighted-Rank approach, which considers the clustering propensity of the binding sites and the overall tendency of regulatory regions to be conserved. In addition, RBPmap incorporates a position-specific background model, designed uniquely for different genomic regions, such as splice sites, 5' and 3' UTRs, non-coding RNA and intergenic regions. RBPmap was tested on high-throughput RNA-binding experiments and was proved to be highly accurate. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  20. Die dogmatiese binding van die prediking

    African Journals Online (AJOL)

    genoemde probleemstelling wat ons homileties na riglyne wil soek, sonder die pretensie dat finale oplossings gevind sal word. Om hierdie probleem te ontleed is dit nodig om eers kortliks 'n begripsbepaling van die begrippe dogma, binding en prediking te maak. Vanuit die begripsbepaling kan ons dan probeer vasstel wat ...

  1. Singular Value Decomposition and Ligand Binding Analysis

    Directory of Open Access Journals (Sweden)

    André Luiz Galo

    2013-01-01

    Full Text Available Singular values decomposition (SVD is one of the most important computations in linear algebra because of its vast application for data analysis. It is particularly useful for resolving problems involving least-squares minimization, the determination of matrix rank, and the solution of certain problems involving Euclidean norms. Such problems arise in the spectral analysis of ligand binding to macromolecule. Here, we present a spectral data analysis method using SVD (SVD analysis and nonlinear fitting to determine the binding characteristics of intercalating drugs to DNA. This methodology reduces noise and identifies distinct spectral species similar to traditional principal component analysis as well as fitting nonlinear binding parameters. We applied SVD analysis to investigate the interaction of actinomycin D and daunomycin with native DNA. This methodology does not require prior knowledge of ligand molar extinction coefficients (free and bound, which potentially limits binding analysis. Data are acquired simply by reconstructing the experimental data and by adjusting the product of deconvoluted matrices and the matrix of model coefficients determined by the Scatchard and McGee and von Hippel equation.

  2. Nucleic acids encoding a cellulose binding domain

    Science.gov (United States)

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1996-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  3. ALG-2, a multifunctional calcium binding protein?

    DEFF Research Database (Denmark)

    Tarabykina, Svetlana; Mollerup, Jens; Winding Gojkovic, P.

    2004-01-01

    ALG-2 was originally discovered as a pro-apoptotic protein in a genetic screen. Due to its ability to bind calcium with high affinity it was postulated to provide a link between the known effect of calcium in programmed cell death and the molecular death execution machinery. This review article...

  4. Tension-induced binding of semiflexible biopolymers

    International Nuclear Information System (INIS)

    Benetatos, Panayotis; Heydt, Alice von der; Zippelius, Annette

    2014-01-01

    We investigate theoretically the effect of polymer tension on the collective behavior of reversibly binding cross-links. For this purpose, we employ a model of two weakly bending wormlike chains aligned in parallel by a tensile force, with a sequence of inter-chain binding sites regularly spaced along the contours. Reversible cross-links attach and detach at the sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and find the emergence of a free-energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the tension increases. We show that this transition is related to the cross-over between weak and strong localization of a directed polymer in a pinning potential. The cross-over to the strongly bound state can be interpreted as a mechanism for force-stiffening which exceeds the capabilities of single-chain elasticity and thus available only to reversibly cross-linked polymers. (paper)

  5. The Binding Properties of Quechua Suffixes.

    Science.gov (United States)

    Weber, David

    This paper sketches an explicitly non-lexicalist application of grammatical theory to Huallaga (Huanuco) Quechua (HgQ). The advantages of applying binding theory to many suffixes that have previously been treated only as objects of the morphology are demonstrated. After an introduction, section 2 outlines basic assumptions about the nature of HgQ…

  6. Asymmetric Aminalization via Cation-Binding Catalysis

    DEFF Research Database (Denmark)

    Park, Sang Yeon; Liu, Yidong; Oh, Joong Suk

    2018-01-01

    Asymmetric cation-binding catalysis, in principle, can generate "chiral" anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen-nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope of the...

  7. Tension-induced binding of semiflexible biopolymers

    Science.gov (United States)

    Benetatos, Panayotis; von der Heydt, Alice; Zippelius, Annette

    2015-03-01

    We investigate theoretically the effect of polymer tension on the collective behaviour of reversible cross-links. We use a model of two parallel-aligned, weakly-bending wormlike chains with a regularly spaced sequence of binding sites subjected to a tensile force. Reversible cross-links attach and detach at the binding sites with an affinity controlled by a chemical potential. In a mean-field approach, we calculate the free energy of the system and we show the emergence of a free energy barrier which controls the reversible (un)binding. The tension affects the conformational entropy of the chains which competes with the binding energy of the cross-links. This competition gives rise to a sudden increase in the fraction of bound sites as the polymer tension increases. The force-induced first-order transition in the number of cross-links implies a sudden force-induced stiffening of the effective stretching modulus of the polymers. This mechanism may be relevant to the formation and stress-induced strengthening of stress fibers in the cytoskeleton. We acknowledge support by the Deutsche Forschungsgemeinschaft (DFG) via grant SFB-937/A1.

  8. Plant ice-binding (antifreeze) proteins

    Science.gov (United States)

    Proteins that determine the temperature at which ice crystals will form in water-based solutions in cells and tissues, that bind to growing ice crystals, thus affecting their size, and that impact ice re-crystallization have been widely-documented and studied in many plant, bacterial, fungal, insect...

  9. The Double Bind: The next Generation

    Science.gov (United States)

    Malcom, Lindsey E.; Malcom, Shirley M.

    2011-01-01

    In this foreword, Shirley Malcom and Lindsey Malcom speak to the history and current status of women of color in science, technology, engineering, and mathematics (STEM) fields. As the author of the seminal report "The Double Bind: The Price of Being a Minority Woman in Science", Shirley Malcom is uniquely poised to give us an insightful…

  10. Binding of cationic surfactants to humic substances

    NARCIS (Netherlands)

    Ishiguro, M.; Tan, W.; Koopal, L.K.

    2007-01-01

    Commercial surfactants are introduced into the environment either through waste products or site-specific contamination. The amphiphilic nature of both surfactants and humic substances (HS) leads to their mutual attraction especially when surfactant and HS are oppositely charged. Binding of the

  11. Overlearned responses hinder S-R binding.

    Science.gov (United States)

    Moeller, Birte; Frings, Christian

    2017-01-01

    Two mechanisms that are important for human action control are the integration of individual action plans (see Hommel, Müsseler, Aschersleben, & Prinz, 2001) and the automatization of overlearned actions to familiar stimuli (see Logan, 1988). In the present study, we analyzed the influence of automatization on action plan integration. Integration with pronunciation responses were compared for response incompatible word and nonword stimuli. Stimulus-response binding effects were observed for nonwords. In contrast, words that automatically triggered an overlearned pronunciation response were not integrated with pronunciation of a different word. That is, automatized response retrieval hindered binding effects regarding the retrieving stimulus and a new response. The results are a first indication of the way that binding and learning processes interact, and might also be a first step to understanding the more complex interdependency of the processes responsible for stimulus-response binding in action control and stimulus-response associations in learning research. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  12. Nucleotide binding to Na+/K+-ATPase

    Czech Academy of Sciences Publication Activity Database

    Kubala, Martin; Lánský, Zdeněk; Ettrich, R.; Plášek, J.; Teisinger, Jan; Amler, Evžen

    2005-01-01

    Roč. 272, č. S1 (2005), s. 191-191 E-ISSN 1742-4658. [FEBS Congress /30./ and IUBMB Conference /9./. 02.07.2005-07.07.2005, Budapest] Keywords : Na+/K+- ATPase * ATP binding * TNP-ATP Subject RIV: BO - Biophysics

  13. Ada To X-Window Bindings

    Science.gov (United States)

    Souleles, Dean

    1993-01-01

    Ada to X-Window Bindings computer program developed to provide Ada programmers with complete interfaces to Xt Intrinsics and OSF Motif toolkits. Provides "Ada view" of some mostly C-language programming libraries. Package of software written in Ada and C languages.

  14. Alkali binding in hydrated Portland cement paste

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, Jos

    2010-01-01

    The alkali-binding capacity of C–S–H in hydrated Portland cement pastes is addressed in this study. The amount of bound alkalis in C–S–H is computed based on the alkali partition theories firstly proposed by Taylor (1987) and later further developed by Brouwers and Van Eijk (2003). Experimental data

  15. Non-binding relationship between visual features

    Directory of Open Access Journals (Sweden)

    Dragan eRangelov

    2014-10-01

    Full Text Available The answer as to how visual attributes processed in different brain loci at different speeds are bound together to give us our unitary experience of the visual world remains unknown. In this study we investigated whether bound representations arise, as commonly assumed, through physiological interactions between cells in the visual areas. In a focal attentional task in which correct responses from either bound or unbound representations were possible, participants discriminated the colour or orientation of briefly presented single bars. On the assumption that representations of the two attributes are bound, the accuracy of reporting the colour and orientation should co-vary. By contrast, if the attributes are not mandatorily bound, the accuracy of reporting the two attributes should be independent. The results of our psychophysical studies reported here supported the latter, non-binding, relationship between visual features, suggesting that binding does not necessarily occur even under focal attention. We propose a task-contingent binding mechanism, postulating that binding occurs at late, post-perceptual, stages through the intervention of memory.

  16. Five of Five VHHs Neutralizing Poliovirus Bind the Receptor-Binding Site.

    Science.gov (United States)

    Strauss, Mike; Schotte, Lise; Thys, Bert; Filman, David J; Hogle, James M

    2016-01-13

    Nanobodies, or VHHs, that recognize poliovirus type 1 have previously been selected and characterized as candidates for antiviral agents or reagents for standardization of vaccine quality control. In this study, we present high-resolution cryo-electron microscopy reconstructions of poliovirus with five neutralizing VHHs. All VHHs bind the capsid in the canyon at sites that extensively overlap the poliovirus receptor-binding site. In contrast, the interaction involves a unique (and surprisingly extensive) surface for each of the five VHHs. Five regions of the capsid were found to participate in binding with all five VHHs. Four of these five regions are known to alter during the expansion of the capsid associated with viral entry. Interestingly, binding of one of the VHHs, PVSS21E, resulted in significant changes of the capsid structure and thus seems to trap the virus in an early stage of expansion. We describe the cryo-electron microscopy structures of complexes of five neutralizing VHHs with the Mahoney strain of type 1 poliovirus at resolutions ranging from 3.8 to 6.3Å. All five VHHs bind deep in the virus canyon at similar sites that overlap extensively with the binding site for the receptor (CD155). The binding surfaces on the VHHs are surprisingly extensive, but despite the use of similar binding surfaces on the virus, the binding surface on the VHHs is unique for each VHH. In four of the five complexes, the virus remains essentially unchanged, but for the fifth there are significant changes reminiscent of but smaller in magnitude than the changes associated with cell entry, suggesting that this VHH traps the virus in a previously undescribed early intermediate state. The neutralizing mechanisms of the VHHs and their potential use as quality control agents for the end game of poliovirus eradication are discussed. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  17. Predicting binding within disordered protein regions to structurally characterised peptide-binding domains.

    Directory of Open Access Journals (Sweden)

    Waqasuddin Khan

    Full Text Available Disordered regions of proteins often bind to structured domains, mediating interactions within and between proteins. However, it is difficult to identify a priori the short disordered regions involved in binding. We set out to determine if docking such peptide regions to peptide binding domains would assist in these predictions.We assembled a redundancy reduced dataset of SLiM (Short Linear Motif containing proteins from the ELM database. We selected 84 sequences which had an associated PDB structures showing the SLiM bound to a protein receptor, where the SLiM was found within a 50 residue region of the protein sequence which was predicted to be disordered. First, we investigated the Vina docking scores of overlapping tripeptides from the 50 residue SLiM containing disordered regions of the protein sequence to the corresponding PDB domain. We found only weak discrimination of docking scores between peptides involved in binding and adjacent non-binding peptides in this context (AUC 0.58.Next, we trained a bidirectional recurrent neural network (BRNN using as input the protein sequence, predicted secondary structure, Vina docking score and predicted disorder score. The results were very promising (AUC 0.72 showing that multiple sources of information can be combined to produce results which are clearly superior to any single source.We conclude that the Vina docking score alone has only modest power to define the location of a peptide within a larger protein region known to contain it. However, combining this information with other knowledge (using machine learning methods clearly improves the identification of peptide binding regions within a protein sequence. This approach combining docking with machine learning is primarily a predictor of binding to peptide-binding sites, and is not intended as a predictor of specificity of binding to particular receptors.

  18. Characterization of wise protein and its molecular mechanism to interact with both Wnt and BMP signals.

    Science.gov (United States)

    Lintern, Katherine B; Guidato, Sonia; Rowe, Alison; Saldanha, José W; Itasaki, Nobue

    2009-08-21

    Cross-talk of BMP and Wnt signaling pathways has been implicated in many aspects of biological events during embryogenesis and in adulthood. A secreted protein Wise and its orthologs (Sostdc1, USAG-1, and Ectodin) have been shown to modulate Wnt signaling and also inhibit BMP signals. Modulation of Wnt signaling activity by Wise is brought about by an interaction with the Wnt co-receptor LRP6, whereas BMP inhibition is by binding to BMP ligands. Here we have investigated the mode of action of Wise on Wnt and BMP signals. It was found that Wise binds LRP6 through one of three loops formed by the cystine knot. The Wise deletion construct lacking the LRP6-interacting loop domain nevertheless binds BMP4 and inhibits BMP signals. Moreover, BMP4 does not interfere with Wise-LRP6 binding, suggesting separate domains for the physical interaction. Functional assays also show that the ability of Wise to block Wnt1 activity through LRP6 is not impeded by BMP4. In contrast, the ability of Wise to inhibit BMP4 is prevented by additional LRP6, implying a preference of Wise in binding LRP6 over BMP4. In addition to the interaction of Wise with BMP4 and LRP6, the molecular characteristics of Wise, such as glycosylation and association with heparan sulfate proteoglycans on the cell surface, are suggested. This study helps to understand the multiple functions of Wise at the molecular level and suggests a possible role for Wise in balancing Wnt and BMP signals.

  19. Acyl-CoA-binding protein/diazepam-binding inhibitor gene and pseudogenes

    DEFF Research Database (Denmark)

    Mandrup, S; Hummel, R; Ravn, S

    1992-01-01

    Acyl-CoA-binding protein (ACBP) is a 10 kDa protein isolated from bovine liver by virtue of its ability to bind and induce the synthesis of medium-chain acyl-CoA esters. Surprisingly, it turned out to be identical to a protein named diazepam-binding Inhibitor (DBI) claimed to be an endogenous mod...... have molecularly cloned and characterized the ACBP/DBI gene family in rat. The rat ACBP/DBI gene family comprises one expressed gene and four processed pseudogenes of which one was shown to exist in two allelic forms. The expressed gene is organized into four exons and three introns...

  20. Chromate Binding and Removal by the Molybdate-Binding Protein ModA.

    Science.gov (United States)

    Karpus, Jason; Bosscher, Michael; Ajiboye, Ifedayo; Zhang, Liang; He, Chuan

    2017-04-04

    Effective and cheap methods and techniques for the safe removal of hexavalent chromate from the environment are in increasingly high demand. High concentrations of hexavalent chromate have been shown to have numerous harmful effects on human biology. We show that the E. coli molybdate-binding protein ModA is a genetically encoded tool capable of removing chromate from aqueous solutions. Although previously reported to not bind chromate, we show that ModA binds chromate tightly and is capable of removing chromate to levels well below current US federal standards. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. A simple ligand-binding assay for thyroxine-binding globulin on reusable Sephadex columns

    International Nuclear Information System (INIS)

    Bastomsky, C.H.; Kalloo, H.; Frenkel-Leith, D.B.; McGill Univ., Montreal, Quebec

    1977-01-01

    A method for the assay of thyroxine-binding globulin on reusable Sephadex G-25 columns is described. It depends upon elution by diluted iodothyronine-free serum of protein-bound [ 125 I]thyroxine from the columns under conditions where binding to thyroxine-binding prealbumin and albumin are abolished. It is simple, rapid and precise, and permits determinations inlarge numbers of samples. Values (mg/l; mean +- S.D.) were: normals 31.6+-5.4, hyperthyroid 28.3+-4.8, hypothyroid 40.6+-7.5, oral contraceptives 40.1+-6.8, pregnant 50.3+-5.4, cirrhotics 20.7+-4.3. Concentrations were reduced in serum heated at 56degC, while the uptake of [ 125 I]triiodothyronine was increased. There was a significant negative correlation between thyroxine-binding globulin concentration and triiodothyronine uptake in the heated serum samples and in euthyroid subjects

  2. Multiple binding modes of ibuprofen in human serum albumin identified by absolute binding free energy calculations

    KAUST Repository

    Evoli, Stefania; Mobley, David L.; Guzzi, Rita; Rizzuti, Bruno

    2016-01-01

    experiments, because of the structural adaptability of this protein in accommodating small ligands. In this work, we provide a set of predictions covering the geometry, affinity of binding and protonation state for the pharmaceutically most active form (S

  3. The inhibition of anti-DNA binding to DNA by nucleic acid binding polymers.

    Directory of Open Access Journals (Sweden)

    Nancy A Stearns

    Full Text Available Antibodies to DNA (anti-DNA are the serological hallmark of systemic lupus erythematosus (SLE and can mediate disease pathogenesis by the formation of immune complexes. Since blocking immune complex formation can attenuate disease manifestations, the effects of nucleic acid binding polymers (NABPs on anti-DNA binding in vitro were investigated. The compounds tested included polyamidoamine dendrimer, 1,4-diaminobutane core, generation 3.0 (PAMAM-G3, hexadimethrine bromide, and a β-cylodextrin-containing polycation. As shown with plasma from patients with SLE, NABPs can inhibit anti-DNA antibody binding in ELISA assays. The inhibition was specific since the NABPs did not affect binding to tetanus toxoid or the Sm protein, another lupus autoantigen. Furthermore, the polymers could displace antibody from preformed complexes. Together, these results indicate that NABPs can inhibit the formation of immune complexes and may represent a new approach to treatment.

  4. Is there a link between selectivity and binding thermodynamics profiles?

    Science.gov (United States)

    Tarcsay, Ákos; Keserű, György M

    2015-01-01

    Thermodynamics of ligand binding is influenced by the interplay between enthalpy and entropy contributions of the binding event. The impact of these binding free energy components, however, is not limited to the primary target only. Here, we investigate the relationship between binding thermodynamics and selectivity profiles by combining publicly available data from broad off-target assay profiling and the corresponding thermodynamics measurements. Our analysis indicates that compounds binding their primary targets with higher entropy contributions tend to hit more off-targets compared with those ligands that demonstrated enthalpy-driven binding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Effect of cobratoxin binding on the normal mode vibration within acetylcholine binding protein.

    Science.gov (United States)

    Bertaccini, Edward J; Lindahl, Erik; Sixma, Titia; Trudell, James R

    2008-04-01

    Recent crystal structures of the acetylcholine binding protein (AChBP) have revealed surprisingly small structural alterations upon ligand binding. Here we investigate the extent to which ligand binding may affect receptor dynamics. AChBP is a homologue of the extracellular component of ligand-gated ion channels (LGICs). We have previously used an elastic network normal-mode analysis to propose a gating mechanism for the LGICs and to suggest the effects of various ligands on such motions. However, the difficulties with elastic network methods lie in their inability to account for the modest effects of a small ligand or mutation on ion channel motion. Here, we report the successful application of an elastic network normal mode technique to measure the effects of large ligand binding on receptor dynamics. The present calculations demonstrate a clear alteration in the native symmetric motions of a protein due to the presence of large protein cobratoxin ligands. In particular, normal-mode analysis revealed that cobratoxin binding to this protein significantly dampened the axially symmetric motion of the AChBP that may be associated with channel gating in the full nAChR. The results suggest that alterations in receptor dynamics could be a general feature of ligand binding.

  6. Sugar-Binding Profiles of Chitin-Binding Lectins from the Hevein Family: A Comprehensive Study

    Directory of Open Access Journals (Sweden)

    Yoko Itakura

    2017-05-01

    Full Text Available Chitin-binding lectins form the hevein family in plants, which are defined by the presence of single or multiple structurally conserved GlcNAc (N-acetylglucosamine-binding domains. Although they have been used as probes for chito-oligosaccharides, their detailed specificities remain to be investigated. In this study, we analyzed six chitin-binding lectins, DSA, LEL, PWM, STL, UDA, and WGA, by quantitative frontal affinity chromatography. Some novel features were evident: WGA showed almost comparable affinity for pyridylaminated chitotriose and chitotetraose, while LEL and UDA showed much weaker affinity, and DSA, PWM, and STL had no substantial affinity for the former. WGA showed selective affinity for hybrid-type N-glycans harboring a bisecting GlcNAc residue. UDA showed extensive binding to high-mannose type N-glycans, with affinity increasing with the number of Man residues. DSA showed the highest affinity for highly branched N-glycans consisting of type II LacNAc (N-acetyllactosamine. Further, multivalent features of these lectins were investigated by using glycoconjugate and lectin microarrays. The lectins showed substantial binding to immobilized LacNAc as well as chito-oligosaccharides, although the extents to which they bound varied among them. WGA showed strong binding to heavily sialylated glycoproteins. The above observations will help interpret lectin-glycoprotein interactions in histochemical studies and glyco-biomarker investigations.

  7. CLIPZ: a database and analysis environment for experimentally determined binding sites of RNA-binding proteins.

    Science.gov (United States)

    Khorshid, Mohsen; Rodak, Christoph; Zavolan, Mihaela

    2011-01-01

    The stability, localization and translation rate of mRNAs are regulated by a multitude of RNA-binding proteins (RBPs) that find their targets directly or with the help of guide RNAs. Among the experimental methods for mapping RBP binding sites, cross-linking and immunoprecipitation (CLIP) coupled with deep sequencing provides transcriptome-wide coverage as well as high resolution. However, partly due to their vast volume, the data that were so far generated in CLIP experiments have not been put in a form that enables fast and interactive exploration of binding sites. To address this need, we have developed the CLIPZ database and analysis environment. Binding site data for RBPs such as Argonaute 1-4, Insulin-like growth factor II mRNA-binding protein 1-3, TNRC6 proteins A-C, Pumilio 2, Quaking and Polypyrimidine tract binding protein can be visualized at the level of the genome and of individual transcripts. Individual users can upload their own sequence data sets while being able to limit the access to these data to specific users, and analyses of the public and private data sets can be performed interactively. CLIPZ, available at http://www.clipz.unibas.ch, aims to provide an open access repository of information for post-transcriptional regulatory elements.

  8. Sequence similarity between the erythrocyte binding domain of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals a functional heparin binding motif involved in binding to the Duffy antigen receptor for chemokines

    Directory of Open Access Journals (Sweden)

    Bolton Michael J

    2011-11-01

    Full Text Available Abstract Background The HIV surface glycoprotein gp120 (SU, gp120 and the Plasmodium vivax Duffy binding protein (PvDBP bind to chemokine receptors during infection and have a site of amino acid sequence similarity in their binding domains that often includes a heparin binding motif (HBM. Infection by either pathogen has been found to be inhibited by polyanions. Results Specific polyanions that inhibit HIV infection and bind to the V3 loop of X4 strains also inhibited DBP-mediated infection of erythrocytes and DBP binding to the Duffy Antigen Receptor for Chemokines (DARC. A peptide including the HBM of PvDBP had similar affinity for heparin as RANTES and V3 loop peptides, and could be specifically inhibited from heparin binding by the same polyanions that inhibit DBP binding to DARC. However, some V3 peptides can competitively inhibit RANTES binding to heparin, but not the PvDBP HBM peptide. Three other members of the DBP family have an HBM sequence that is necessary for erythrocyte binding, however only the protein which binds to DARC, the P. knowlesi alpha protein, is inhibited by heparin from binding to erythrocytes. Heparitinase digestion does not affect the binding of DBP to erythrocytes. Conclusion The HBMs of DBPs that bind to DARC have similar heparin binding affinities as some V3 loop peptides and chemokines, are responsible for specific sulfated polysaccharide inhibition of parasite binding and invasion of red blood cells, and are more likely to bind to negative charges on the receptor than cell surface glycosaminoglycans.

  9. Comparison of Transcription Factor Binding Site Models

    KAUST Repository

    Bhuyan, Sharifulislam

    2012-05-01

    Modeling of transcription factor binding sites (TFBSs) and TFBS prediction on genomic sequences are important steps to elucidate transcription regulatory mechanism. Dependency of transcription regulation on a great number of factors such as chemical specificity, molecular structure, genomic and epigenetic characteristics, long distance interaction, makes this a challenging problem. Different experimental procedures generate evidence that DNA-binding domains of transcription factors show considerable DNA sequence specificity. Probabilistic modeling of TFBSs has been moderately successful in identifying patterns from a family of sequences. In this study, we compare performances of different probabilistic models and try to estimate their efficacy over experimental TFBSs data. We build a pipeline to calculate sensitivity and specificity from aligned TFBS sequences for several probabilistic models, such as Markov chains, hidden Markov models, Bayesian networks. Our work, containing relevant statistics and evaluation for the models, can help researchers to choose the most appropriate model for the problem at hand.

  10. Quantifying drug-protein binding in vivo

    International Nuclear Information System (INIS)

    Buchholz, B; Bench, G; Keating III, G; Palmblad, M; Vogel, J; Grant, P G; Hillegonds, D

    2004-01-01

    Accelerator mass spectrometry (AMS) provides precise quantitation of isotope labeled compounds that are bound to biological macromolecules such as DNA or proteins. The sensitivity is high enough to allow for sub-pharmacological (''micro-'') dosing to determine macromolecular targets without inducing toxicities or altering the system under study, whether it is healthy or diseased. We demonstrated an application of AMS in quantifying the physiologic effects of one dosed chemical compound upon the binding level of another compound in vivo at sub-toxic doses [4].We are using tissues left from this study to develop protocols for quantifying specific binding to isolated and identified proteins. We also developed a new technique to quantify nanogram to milligram amounts of isolated protein at precisions that are comparable to those for quantifying the bound compound by AMS

  11. RNA-Binding Proteins in Plant Immunity

    Directory of Open Access Journals (Sweden)

    Virginia Woloshen

    2011-01-01

    Full Text Available Plant defence responses against pathogen infection are crucial to plant survival. The high degree of regulation of plant immunity occurs both transcriptionally and posttranscriptionally. Once transcribed, target gene RNA must be processed prior to translation. This includes polyadenylation, 5′capping, editing, splicing, and mRNA export. RNA-binding proteins (RBPs have been implicated at each level of RNA processing. Previous research has primarily focused on structural RNA-binding proteins of yeast and mammals; however, more recent work has characterized a number of plant RBPs and revealed their roles in plant immune responses. This paper provides an update on the known functions of RBPs in plant immune response regulation. Future in-depth analysis of RBPs and other related players will unveil the sophisticated regulatory mechanisms of RNA processing during plant immune responses.

  12. Binding of 3H-iloprost to rat gastric mucosa: a pitfall in performing radioligand binding assays

    International Nuclear Information System (INIS)

    Beinborn, M.; Kromer, W.; Staar, U.; Sewing, K.F.

    1985-01-01

    Binding of 3 H-iloprost was studied in a 20,000 x g sediment of the rat gastric mucosa. When pH in both test tubes for total and non-specific binding was kept identical, no displaceable binding of iloprost could be detected. When no care was taken to keep the pH identical in corresponding test tubes of the binding assay, changes in pH simulated specific and displaceable binding of iloprost. Therefore it is concluded that - in contrast to earlier reports - it is not possible to demonstrate specific iloprost binding using the given method

  13. Surface Passivation in Empirical Tight Binding

    OpenAIRE

    He, Yu; Tan, Yaohua; Jiang, Zhengping; Povolotskyi, Michael; Klimeck, Gerhard; Kubis, Tillmann

    2015-01-01

    Empirical Tight Binding (TB) methods are widely used in atomistic device simulations. Existing TB methods to passivate dangling bonds fall into two categories: 1) Method that explicitly includes passivation atoms is limited to passivation with atoms and small molecules only. 2) Method that implicitly incorporates passivation does not distinguish passivation atom types. This work introduces an implicit passivation method that is applicable to any passivation scenario with appropriate parameter...

  14. Oxygen binding to partially nitrosylated hemoglobin.

    Science.gov (United States)

    Fago, Angela; Crumbliss, Alvin L; Hendrich, Michael P; Pearce, Linda L; Peterson, Jim; Henkens, Robert; Bonaventura, Celia

    2013-09-01

    Reactions of nitric oxide (NO) with hemoglobin (Hb) are important elements in protection against nitrosative damage. NO in the vasculature is depleted by the oxidative reaction with oxy Hb or by binding to deoxy Hb to generate partially nitrosylated Hb (Hb-NO). Many aspects of the formation and persistence of Hb-NO are yet to be clarified. In this study, we used a combination of EPR and visible absorption spectroscopy to investigate the interactions of partially nitrosylated Hb with O2. Partially nitrosylated Hb samples had predominantly hexacoordinate NO-heme geometry and resisted oxidation when exposed to O2 in the absence of anionic allosteric effectors. Faster oxidation occurred in the presence of 2,3-diphosphoglycerate (DPG) or inositol hexaphosphate (IHP), where the NO-heme derivatives had higher levels of pentacoordinate heme geometry. The anion-dependence of the NO-heme geometry also affected O2 binding equilibria. O2-binding curves of partially nitrosylated Hb in the absence of anions were left-shifted at low saturations, indicating destabilization of the low O2 affinity T-state of the Hb by increasing percentages of NO-heme, much as occurs with increasing levels of CO-heme. Samples containing IHP showed small decreases in O2 affinity, indicating shifts toward the low-affinity T-state and formation of inert α-NO/β-met tetramers. Most remarkably, O2-equilibria in the presence of the physiological effector DPG were essentially unchanged by up to 30% NO-heme in the samples. As will be discussed, under physiological conditions the interactions of Hb with NO provide protection against nitrosative damage without impairing O2 transport by Hb's unoccupied heme sites. This article is part of a Special Issue entitled: Oxygen Binding and Sensing Proteins. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Predicting protein-binding RNA nucleotides with consideration of binding partners.

    Science.gov (United States)

    Tuvshinjargal, Narankhuu; Lee, Wook; Park, Byungkyu; Han, Kyungsook

    2015-06-01

    In recent years several computational methods have been developed to predict RNA-binding sites in protein. Most of these methods do not consider interacting partners of a protein, so they predict the same RNA-binding sites for a given protein sequence even if the protein binds to different RNAs. Unlike the problem of predicting RNA-binding sites in protein, the problem of predicting protein-binding sites in RNA has received little attention mainly because it is much more difficult and shows a lower accuracy on average. In our previous study, we developed a method that predicts protein-binding nucleotides from an RNA sequence. In an effort to improve the prediction accuracy and usefulness of the previous method, we developed a new method that uses both RNA and protein sequence data. In this study, we identified effective features of RNA and protein molecules and developed a new support vector machine (SVM) model to predict protein-binding nucleotides from RNA and protein sequence data. The new model that used both protein and RNA sequence data achieved a sensitivity of 86.5%, a specificity of 86.2%, a positive predictive value (PPV) of 72.6%, a negative predictive value (NPV) of 93.8% and Matthews correlation coefficient (MCC) of 0.69 in a 10-fold cross validation; it achieved a sensitivity of 58.8%, a specificity of 87.4%, a PPV of 65.1%, a NPV of 84.2% and MCC of 0.48 in independent testing. For comparative purpose, we built another prediction model that used RNA sequence data alone and ran it on the same dataset. In a 10 fold-cross validation it achieved a sensitivity of 85.7%, a specificity of 80.5%, a PPV of 67.7%, a NPV of 92.2% and MCC of 0.63; in independent testing it achieved a sensitivity of 67.7%, a specificity of 78.8%, a PPV of 57.6%, a NPV of 85.2% and MCC of 0.45. In both cross-validations and independent testing, the new model that used both RNA and protein sequences showed a better performance than the model that used RNA sequence data alone in

  16. Binding Energy and Equilibrium of Compact Objects

    Directory of Open Access Journals (Sweden)

    Germano M.

    2014-04-01

    Full Text Available The theoretical analysis of the existence of a limit mass for compact astronomic ob- jects requires the solution of the Einstein’s equations of g eneral relativity together with an appropriate equation of state. Analytical solutions exi st in some special cases like the spherically symmetric static object without energy sou rces that is here considered. Solutions, i.e. the spacetime metrics, can have a singular m athematical form (the so called Schwarzschild metric due to Hilbert or a nonsingula r form (original work of Schwarzschild. The former predicts a limit mass and, conse quently, the existence of black holes above this limit. Here it is shown that, the origi nal Schwarzschild met- ric permits compact objects, without mass limit, having rea sonable values for central density and pressure. The lack of a limit mass is also demonst rated analytically just imposing reasonable conditions on the energy-matter densi ty, of positivity and decreas- ing with radius. Finally the ratio between proper mass and to tal mass tends to 2 for high values of mass so that the binding energy reaches the lim it m (total mass seen by a distant observer. As it is known the negative binding energ y reduces the gravitational mass of the object; the limit of m for the binding energy provides a mechanism for stable equilibrium of any amount of mass to contrast the gravitatio nal collapse.

  17. What Happened to the IGF Binding Proteins?

    Science.gov (United States)

    Bach, Leon A

    2018-02-01

    Insulinlike growth factor (IGF) binding proteins (IGFBPs) 1 to 6 are high-affinity regulators of IGF activity. They generally inhibit IGF actions by preventing binding to the IGF-I receptor but can also enhance their actions under some conditions. Posttranslational modifications such as glycosylation and phosphorylation modulate IGFBP properties, and IGFBP proteolysis results in IGF release. IGFBPs have more recently been shown to have IGF-independent actions. A number of mechanisms are involved, including modulation of other growth factor pathways, nuclear localization and transcriptional regulation, interaction with the sphingolipid pathway, and binding to non-IGF biomolecules in the extracellular space and matrix, on the cell surface and intracellularly. IGFBPs modulate important biological processes, including cell proliferation, survival, migration, senescence, autophagy, and angiogenesis. Their actions have been implicated in growth, metabolism, cancer, stem cell maintenance and differentiation, and immune regulation. Recent studies have shown that epigenetic mechanisms are involved in the regulation of IGFBP abundance. A more complete understanding of IGFBP biology is necessary to further define their cellular roles and determine their therapeutic potential. Copyright © 2018 Endocrine Society.

  18. Photoaffinity labeling of the oxysterol binding protein

    International Nuclear Information System (INIS)

    Taylor, F.R.; Kandutsch, A.A.; Anzalone, L.; Spencer, T.A.

    1986-01-01

    A cytosolic receptor protein for oxygenated sterols, that is thought to be involved in the regulation of HMG-CoA reductase and cholesterol biosynthesis, can be labeled covalently by the photoactivated affinity compound [5,6- 3 H]-7,7'-azocholestane-3β,25-diol (I). Several other compounds were tested including 25-hydroxycholesta-4,6-dien-3-one, 25-azido-27-norcholest-5-en-3β-ol,3β,25-dihydroxycholest-5-en-7-one and 3β-hydroxycholesta-8(14),9(11)-dien-15-one. However, these sterols either did not bind to the receptor with adequate affinity or did not react covalently with the receptor during photolysis. Compound I binds to the receptor with very high affinity (K/sub d/ = 30 nM). After activation with long wavelength UV, two tritium labeled proteins, M/sub r/ approximately 95K and 65K daltons, are found upon SDS gel electrophoresis. No labeling occurs when the binding reaction is carried out in the presence of a large excess of 25-hydroxycholesterol. It is possible that the smaller polypeptide is a degradation product. Under the reaction conditions investigated so far labeling is relatively inefficient (< 1% of bound sterol). These results are generally consistent with previous information suggesting that the M/sub r/ of the receptor subunit is 97,000. Covalent labeling of the receptor should greatly facilitate its further purification and characterization

  19. Solid-Binding Peptides in Biomedicine.

    Science.gov (United States)

    Care, Andrew; Bergquist, Peter L; Sunna, Anwar

    2017-01-01

    Some peptides are able to bind to inorganic materials such as silica and gold. Over the past decade, Solid-binding peptides (SBPs) have been used increasingly as molecular building blocks in nanobiotechnology. These peptides show selectivity and bind with high affinity to a diverse range of inorganic surfaces e.g. metals, metal oxides, metal compounds, magnetic materials, semiconductors, carbon materials, polymers and minerals. They can be used in applications such as protein purification and synthesis, assembly and the functionalization of nanomaterials. They offer simple and versatile bioconjugation methods that can increase biocompatibility and also direct the immobilization and orientation of nanoscale entities onto solid supports without impeding their functionality. SBPs have been employed in numerous nanobiotechnological applications such as the controlled synthesis of nanomaterials and nanostructures, formation of hybrid biomaterials, immobilization of functional proteins and improved nanomaterial biocompatibility. With advances in nanotechnology, a multitude of novel nanomaterials have been designed and synthesized for diagnostic and therapeutic applications. New approaches have been developed recently to exert a greater control over bioconjugation and eventually, over the optimal and functional display of biomolecules on the surfaces of many types of solid materials. In this chapter we describe SBPs and highlight some selected examples of their potential applications in biomedicine.

  20. Metal ion binding with dehydroannulenes – Plausible two ...

    Indian Academy of Sciences (India)

    WINTEC

    Theoretical investigations have been carried out at B3LYP/6-311++G** level of theory to study the binding ... Alkali metals; dehydroannulenes; binding energy; penetration barrier. 1. .... can be discriminated from larger metal ions by running.

  1. Binding of tritiated corticosterone in brain sections of adrenalectomized rat

    International Nuclear Information System (INIS)

    Sarrieau, A.; Vial, M.; Dussaillant, M.; Rostene, W.; Philibert, P.

    1983-01-01

    A new technique which permits to study the specific binding of tritiated corticosterone in brain sections of adrenalectomized rats is described. Under these conditions, the specific binding of the glucocorticoid represents 60 to 70% of the initial binding. The apparent dissociation constant and the number of binding sites, determined by Scatchard analysis, are in the range of 10 -8 M and 100 fmoles/mg of protein respectively [fr

  2. Binding of Intrinsic and Extrinsic Features in Working Memory

    Science.gov (United States)

    Ecker, Ullrich K. H.; Maybery, Murray; Zimmer, Hubert D.

    2013-01-01

    There is ongoing debate concerning the mechanisms of feature binding in working memory. In particular, there is controversy regarding the extent to which these binding processes are automatic. The present article demonstrates that binding mechanisms differ depending on whether the to-be-integrated features are perceived as forming a coherent…

  3. Cobalamin and its binding protein in rat milk

    DEFF Research Database (Denmark)

    Raaberg, Lasse; Nexø, Ebba; Poulsen, Steen Seier

    1989-01-01

    Cobalamin and its binding protein, haptocorrin, are present in rat milk throughout the lactation period. The concentration of cobalamin is approximately 0.3-times the concentration of the unsaturated binding protein. The concentration of the unsaturated cobalamin-binding protein varies between 18...

  4. A structural classification of substrate-binding proteins

    NARCIS (Netherlands)

    Berntsson, Ronnie P. -A.; Smits, Sander H. J.; Schmitt, Lutz; Slotboom, Dirk-Jan; Poolman, Bert

    2010-01-01

    Substrate-binding proteins (SBP) are associated with a wide variety of protein complexes. The proteins are part of ATP-binding cassette transporters for substrate uptake, ion gradient driven transporters, DNA-binding proteins, as well as channels and receptors from both pro-and eukaryotes. A wealth

  5. Thioredoxin binding site of phosphoribulokinase overlaps the catalytic site

    International Nuclear Information System (INIS)

    Porter, M.A.; Hartman, F.C.

    1986-01-01

    The ATP-regulatory binding site of phosphoribulokinase was studied using bromoacetylethanolamine phosphate (BrAcNHEtOP). BrAcNHEtOP binds to the active-regulatory binding site of the protein. Following trypsin degradation of the labeled protein, fragments were separated by HPLC and sequenced. (DT)

  6. Atomistic fingerprint of hyaluronan-CD44 binding

    DEFF Research Database (Denmark)

    Vuorio, Joni; Vattulainen, Ilpo; Martinez-Seara, Hector

    2017-01-01

    that hyaluronan can bind CD44 with three topographically different binding modes that in unison define an interaction fingerprint, thus providing a plausible explanation for the disagreement between the earlier studies. Our results confirm that the known crystallographic mode is the strongest of the three binding...

  7. Fractionating the Binding Process: Neuropsychological Evidence from Reversed Search Efficiencies

    Science.gov (United States)

    Humphreys, Glyn W.; Hodsoll, John; Riddoch, M. Jane

    2009-01-01

    The authors present neuropsychological evidence distinguishing binding between form, color, and size (cross-domain binding) and binding between form elements. They contrasted conjunctive search with difficult feature search using control participants and patients with unilateral parietal or fronto/temporal lesions. To rule out effects of task…

  8. A sequential binding mechanism in a PDZ domain

    DEFF Research Database (Denmark)

    Chi, Celestine N; Bach, Anders; Engström, Åke

    2009-01-01

    that ligand binding involves at least a two-step process. By using an ultrarapid continuous-flow mixer, we then detected a hyperbolic dependence of binding rate constants on peptide concentration, corroborating the two-step binding mechanism. Furthermore, we found a similar dependence of the rate constants...

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

    Science.gov (United States)

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

    2006-05-20

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

  10. Tritium NMR spectroscopy of ligand binding to maltose-binding protein

    International Nuclear Information System (INIS)

    Gehring, K.; Williams, P.G.; Pelton, J.G.; Morimoto, H.; Wemmer, D.E.

    1991-01-01

    Tritium-labeled α- and β-maltodextrins have been used to study their complexes with maltose-binding protein (MBP), a 40-kDa bacterial protein. Five substrates, from maltose to maltohexaose, were labeled at their reducing ends and their binding studied. Tritium NMR specctroscopy of the labeled sugars showed large upfield chamical shift changes upon binding and strong anomeric specficity. At 10 degrees C, MBP bound α-maltose with 2.7 ± 0.5-fold higher affinity than β-maltose, and, for longer maltodextrins, the ratio of affinities was even larger. The maximum chemical shift change was 2.2 ppm, suggesting that the reducing end of bound α-maltodextrin makes close contact with an aromatic residue in the MBP-binding site. Experiments with maltotriose (and longer maltodextrins) also revealed the presence of two bound β-maltotriose resonances in rapid exchange. The authors interpret these two resonances as arising from two distinct sugar-protein complexes. In one complex, the β-maltodextrin is bound by its reducing end, and, in the other complex, the β-maltodextrin is bound by the middle glucose residue(s). This interpretation also suggests how MBP is able to bind both linear and circular maltodextrins

  11. Substrate-Triggered Exosite Binding: Synergistic Dendrimer/Folic Acid Action for Achieving Specific, Tight-Binding to Folate Binding Protein.

    Science.gov (United States)

    Chen, Junjie; van Dongen, Mallory A; Merzel, Rachel L; Dougherty, Casey A; Orr, Bradford G; Kanduluru, Ananda Kumar; Low, Philip S; Marsh, E Neil G; Banaszak Holl, Mark M

    2016-03-14

    Polymer-ligand conjugates are designed to bind proteins for applications as drugs, imaging agents, and transport scaffolds. In this work, we demonstrate a folic acid (FA)-triggered exosite binding of a generation five poly(amidoamine) (G5 PAMAM) dendrimer scaffold to bovine folate binding protein (bFBP). The protein exosite is a secondary binding site on the protein surface, separate from the FA binding pocket, to which the dendrimer binds. Exosite binding is required to achieve the greatly enhanced binding constants and protein structural change observed in this study. The G5Ac-COG-FA1.0 conjugate bound tightly to bFBP, was not displaced by a 28-fold excess of FA, and quenched roughly 80% of the initial fluorescence. Two-step binding kinetics were measured using the intrinsic fluorescence of the FBP tryptophan residues to give a KD in the low nanomolar range for formation of the initial G5Ac-COG-FA1.0/FBP* complex, and a slow conversion to the tight complex formed between the dendrimer and the FBP exosite. The extent of quenching was sensitive to the choice of FA-dendrimer linker chemistry. Direct amide conjugation of FA to G5-PAMAM resulted in roughly 50% fluorescence quenching of the FBP. The G5Ac-COG-FA, which has a longer linker containing a 1,2,3-triazole ring, exhibited an ∼80% fluorescence quenching. The binding of the G5Ac-COG-FA1.0 conjugate was compared to poly(ethylene glycol) (PEG) conjugates of FA (PEGn-FA). PEG2k-FA had a binding strength similar to that of FA, whereas other PEG conjugates with higher molecular weight showed weaker binding. However, no PEG conjugates gave an increased degree of total fluorescence quenching.

  12. LHRH-pituitary plasma membrane binding: the presence of specific binding sites in other tissues.

    Science.gov (United States)

    Marshall, J C; Shakespear, R A; Odell, W D

    1976-11-01

    Two specific binding sites for LHRH are present on plasma membranes prepared from rat and bovine anterior pituitary glands. One site is of high affinity (K = 2X108 1/MOL) and the second is of lower affinity (8-5X105 1/mol) and much greater capacity. Studies on membrane fractions prepared from other tissues showed the presence of a single specific site for LHRH. The kinetics and specificity of this site were similar to those of the lower affinity pituitary receptor. These results indicate that only pituitary membranes possess the higher affinity binding site and suggest that the low affinity site is not of physiological importance in the regulation of gonadotrophin secretion. After dissociation from membranes of non-pituitary tissues 125I-LHRH rebound to pituitary membrane preparations. Thus receptor binding per se does not result in degradation of LHRH and the function of these peripheral receptors remains obscure.

  13. Sequence similarity between the erythrocyte binding domain of the Plasmodium vivax Duffy binding protein and the V3 loop of HIV-1 strain MN reveals a functional heparin binding motif involved in binding to the Duffy antigen receptor for chemokines

    OpenAIRE

    Bolton, Michael J; Garry, Robert F

    2011-01-01

    Abstract Background The HIV surface glycoprotein gp120 (SU, gp120) and the Plasmodium vivax Duffy binding protein (PvDBP) bind to chemokine receptors during infection and have a site of amino acid sequence similarity in their binding domains that often includes a heparin binding motif (HBM). Infection by either pathogen has been found to be inhibited by polyanions. Results Specific polyanions that inhibit HIV infection and bind to the V3 loop of X4 strains also inhibited DBP-mediated infectio...

  14. Autoradiographic localization of benzomorphan binding sites in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Crain, B.J.; Kwenjen Chang; McNamara, J.O.; Valdes, F.

    1985-07-17

    The benzomorphan subpopulation of opiate binding sites was labeled by (TH)diprenorphine in the presence of unlabeled ligands selected to quench and delta opiate binding sites. The distribution of benzomorphan binding sites was then localized autoradiographically. The distribution differs from the distributions of , delta and kappa opiate binding and is quite similar to the distribution of US -endorphin immunoreactivity. These observations support the hypothesis, based on biochemical studies in brain membranes, that benzomorphan binding sites may represent the ligand recognition sites of putative epsilon receptors. (Auth.). 34 refs.; 3 figs.

  15. How Arousal Affects Younger and Older Adults' Memory Binding

    Science.gov (United States)

    Nashiro, Kaoru; Mather, Mara

    2009-01-01

    A number of recent studies have shown that associative memory for within-item features is enhanced for emotionally arousing items, whereas arousal-enhanced binding is not seen for associations between distinct items (for a review see Mather, 2007). The costs and benefits of arousal in memory binding have been examined for younger adults but not for older adults. The present experiment examined whether arousal would enhance younger and older adults' within-item and between-item memory binding. The results revealed that arousal improved younger adults' within-item memory binding but not that of older adults. Arousal worsened both groups' between-item memory binding. PMID:21240821

  16. Study of plasma binding of receptor-specific peptides

    OpenAIRE

    Gregor, David

    2008-01-01

    The binding ability of two receptor specific peptides namely 90Y-DOTA-TATE and 111In-DOTA-TATE was studied in therm of interspecies comparison by the method of equilibrium dialysis. This plasma protein binding was different for the chosen animal species (human, rat, rabbit, bovine eventually pork) whereas binding of 90Y-DOTA- TATE was higher than binding of 111In-DOTA-TATE. KEYWORDS: Protein binding, radiofarmaceuticals, equilibrium dialysis, 90Y-DOTA-TATE, 111In- DOTA-TATE

  17. Protein-binding RNA aptamers affect molecular interactions distantly from their binding sites.

    Directory of Open Access Journals (Sweden)

    Daniel M Dupont

    Full Text Available Nucleic acid aptamer selection is a powerful strategy for the development of regulatory agents for molecular intervention. Accordingly, aptamers have proven their diligence in the intervention with serine protease activities, which play important roles in physiology and pathophysiology. Nonetheless, there are only a few studies on the molecular basis underlying aptamer-protease interactions and the associated mechanisms of inhibition. In the present study, we use site-directed mutagenesis to delineate the binding sites of two 2´-fluoropyrimidine RNA aptamers (upanap-12 and upanap-126 with therapeutic potential, both binding to the serine protease urokinase-type plasminogen activator (uPA. We determine the subsequent impact of aptamer binding on the well-established molecular interactions (plasmin, PAI-1, uPAR, and LRP-1A controlling uPA activities. One of the aptamers (upanap-126 binds to the area around the C-terminal α-helix in pro-uPA, while the other aptamer (upanap-12 binds to both the β-hairpin of the growth factor domain and the kringle domain of uPA. Based on the mapping studies, combined with data from small-angle X-ray scattering analysis, we construct a model for the upanap-12:pro-uPA complex. The results suggest and highlight that the size and shape of an aptamer as well as the domain organization of a multi-domain protein such as uPA, may provide the basis for extensive sterical interference with protein ligand interactions considered distant from the aptamer binding site.

  18. Thyroxine binding to serum thyronine-binding globulin in thyroidectomized adult and normal neonatal rats

    International Nuclear Information System (INIS)

    Young, R.A.; Meyers, B.; Alex, S.; Fang, S.L.; Braverman, L.E.

    1988-01-01

    The amount of tracer [125I]T4 bound to serum thyronine-binding globulin (TBG) was measured by polyacrylamide gel electrophoresis in adult thyroidectomized (TX) rats and normal 1-day to 4-week-old rat puts. Thyroidectomy was associated with the appearance of significant amounts of [125I]T4 binding to serum TBG in lean rats, but not in obese Zucker rats. Treatment of the TX rats in vivo with replacement doses of T4 prevented this increase in TBG binding, but enrichment of serum from TX rats with T4 did not. Significant amounts of tracer [125I]T4 binding to TBG was present in serum from 1- to 3-week-old normal rat pups, but not in 1-day- or 4-week-old pups. There were significantly higher levels of TBG binding of [125I]T4 in serum from 2-week-old rat pups raised in litters of 16 pups compared to those raised in litters of 4 pups. All manipulations that result in the appearance of TBG in rat serum also result in either weight loss or a slowing in the rate of growth, suggesting that the appearance of TBG in rat serum has a nutritional component. This possibility is further supported by the observations that increases in TBG binding of [125I]T4 are not found in obese Zucker rats fed a low protein-high carbohydrate diet for 14 days or fasted for 7 days, or after thyroidectomy, perhaps owing to the large stores of fuel in the obese rat

  19. Human pentraxin 3 binds to the complement regulator c4b-binding protein.

    Directory of Open Access Journals (Sweden)

    Anne Braunschweig

    Full Text Available The long pentraxin 3 (PTX3 is a soluble recognition molecule with multiple functions including innate immune defense against certain microbes and the clearance of apoptotic cells. PTX3 interacts with recognition molecules of the classical and lectin complement pathways and thus initiates complement activation. In addition, binding of PTX3 to the alternative complement pathway regulator factor H was shown. Here, we show that PTX3 binds to the classical and lectin pathway regulator C4b-binding protein (C4BP. A PTX3-binding site was identified within short consensus repeats 1-3 of the C4BP α-chain. PTX3 did not interfere with the cofactor activity of C4BP in the fluid phase and C4BP maintained its complement regulatory activity when bound to PTX3 on surfaces. While C4BP and factor H did not compete for PTX3 binding, the interaction of C4BP with PTX3 was inhibited by C1q and by L-ficolin. PTX3 bound to human fibroblast- and endothelial cell-derived extracellular matrices and recruited functionally active C4BP to these surfaces. Whereas PTX3 enhanced the activation of the classical/lectin pathway and caused enhanced C3 deposition on extracellular matrix, deposition of terminal pathway components and the generation of the inflammatory mediator C5a were not increased. Furthermore, PTX3 enhanced the binding of C4BP to late apoptotic cells, which resulted in an increased rate of inactivation of cell surface bound C4b and a reduction in the deposition of C5b-9. Thus, in addition to complement activators, PTX3 interacts with complement inhibitors including C4BP. This balanced interaction on extracellular matrix and on apoptotic cells may prevent excessive local complement activation that would otherwise lead to inflammation and host tissue damage.

  20. Antioxidant flavonoids bind human serum albumin

    Science.gov (United States)

    Kanakis, C. D.; Tarantilis, P. A.; Polissiou, M. G.; Diamantoglou, S.; Tajmir-Riahi, H. A.

    2006-10-01

    Human serum albumin (HSA) is a principal extracellular protein with a high concentration in blood plasma and carrier for many drugs to different molecular targets. Flavonoids are powerful antioxidants and prevent DNA damage. The antioxidative protections are related to their binding modes to DNA duplex and complexation with free radicals in vivo. However, flavonoids are known to inhibit the activities of several enzymes such as calcium phospholipid-dependent protein kinase, tyrosine protein kinase from rat lung, phosphorylase kinase, phosphatidylinositol 3-kinase and DNA topoisomerases that exhibit the importance of flavonoid-protein interaction. This study was designed to examine the interaction of human serum albumin (HSA) with quercetin (que), kaempferol (kae) and delphinidin (del) in aqueous solution at physiological conditions, using constant protein concentration of 0.25 mM (final) and various drug contents of 1 μM-1 mM. FTIR and UV-vis spectroscopic methods were used to determine the polyphenolic binding mode, the binding constant and the effects of flavonoid complexation on protein secondary structure. The spectroscopic results showed that flavonoids are located along the polypeptide chains through H-bonding interactions with overall affinity constant of Kque = 1.4 × 10 4 M -1, Kkae = 2.6 × 10 5 M -1 and Kdel = 4.71 × 10 5 M -1. The protein secondary structure showed no alterations at low pigment concentration (1 μM), whereas at high flavonoid content (1 mM), major reduction of α-helix from 55% (free HSA) to 42-46% and increase of β-sheet from 15% (free HSA) to 17-19% and β-anti from 7% (free HSA) to 10-20% occurred in the flavonoid-HSA adducts. The major reduction of HSA α-helix is indicative of a partial protein unfolding upon flavonoid interaction.

  1. Metal ion binding to iron oxides

    Science.gov (United States)

    Ponthieu, M.; Juillot, F.; Hiemstra, T.; van Riemsdijk, W. H.; Benedetti, M. F.

    2006-06-01

    The biogeochemistry of trace elements (TE) is largely dependent upon their interaction with heterogeneous ligands including metal oxides and hydrous oxides of iron. The modeling of TE interactions with iron oxides has been pursued using a variety of chemical models. The objective of this work is to show that it is possible to model the adsorption of protons and TE on a crystallized oxide (i.e., goethite) and on an amorphous oxide (HFO) in an identical way. Here, we use the CD-MUSIC approach in combination with valuable and reliable surface spectroscopy information about the nature of surface complexes of the TE. The other objective of this work is to obtain generic parameters to describe the binding of the following elements (Cd, Co, Cu, Ni, Pb, and Zn) onto both iron oxides for the CD-MUSIC approach. The results show that a consistent description of proton and metal ion binding is possible for goethite and HFO with the same set of model parameters. In general a good prediction of almost all the collected experimental data sets corresponding to metal ion binding to HFO is obtained. Moreover, dominant surface species are in agreement with the recently published surface complexes derived from X-ray absorption spectroscopy (XAS) data. Until more detailed information on the structure of the two iron oxides is available, the present option seems a reasonable approximation and can be used to describe complex geochemical systems. To improve our understanding and modeling of multi-component systems we need more data obtained at much lower metal ion to iron oxide ratios in order to be able to account eventually for sites that are not always characterized in spectroscopic studies.

  2. Interaction of Wnt Signaling with BMP/Smad Signaling during the Transition from Cell Proliferation to Myogenic Differentiation in Mouse Myoblast-Derived Cells

    Directory of Open Access Journals (Sweden)

    Kumiko Terada

    2013-01-01

    Full Text Available Background. Wnt signaling is involved in muscle formation through β-catenin-dependent or -independent pathways, but interactions with other signaling pathways including transforming growth factor β/Smad have not been precisely elucidated. Results.