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Poole K, Iyer KS, Schmidtke DW, Petroll WM, Varner VD. Corneal keratocytes, fibroblasts, and myofibroblasts exhibit distinct transcriptional profiles in vitro. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.28.582620. [PMID: 38464034 PMCID: PMC10925317 DOI: 10.1101/2024.02.28.582620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Purpose After stromal injury to the cornea, the release of growth factors and pro-inflammatory cytokines promotes the activation of quiescent keratocytes into a migratory fibroblast and/or fibrotic myofibroblast phenotype. Persistence of the myofibroblast phenotype can lead to corneal fibrosis and scarring, which are leading causes of blindness worldwide. This study aims to establish comprehensive transcriptional profiles for cultured corneal keratocytes, fibroblasts, and myofibroblasts to gain insights into the mechanisms through which these phenotypic changes occur. Methods Primary rabbit corneal keratocytes were cultured in either defined serum-free media (SF), fetal bovine serum (FBS) containing media, or in the presence of TGF-β1 to induce keratocyte, fibroblast, or myofibroblast phenotypes, respectively. Bulk RNA sequencing followed by bioinformatic analyses was performed to identify significant differentially expressed genes (DEGs) and enriched biological pathways for each phenotype. Results Genes commonly associated with keratocytes, fibroblasts, or myofibroblasts showed high relative expression in SF, FBS, or TGF-β1 culture conditions, respectively. Differential expression and functional analyses revealed novel DEGs for each cell type, as well as enriched pathways indicative of differences in proliferation, apoptosis, extracellular matrix (ECM) synthesis, cell-ECM interactions, cytokine signaling, and cell mechanics. Conclusions Overall, these data demonstrate distinct transcriptional differences among cultured corneal keratocytes, fibroblasts, and myofibroblasts. We have identified genes and signaling pathways that may play important roles in keratocyte differentiation, including many related to mechanotransduction and ECM biology. Our findings have revealed novel molecular markers for each cell type, as well as possible targets for modulating cell behavior and promoting physiological corneal wound healing.
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Hynek R, Michalus I, Cejnar P, Šantrůček J, Seidlová S, Kučková Š, Sázelová P, Kašička V. In-bone protein digestion followed by LC-MS/MS peptide analysis as a new way towards the routine proteomic characterization of human maxillary and mandibular bone tissue in oral surgery. Electrophoresis 2021; 42:2552-2562. [PMID: 34453862 DOI: 10.1002/elps.202100211] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 08/12/2021] [Accepted: 08/26/2021] [Indexed: 11/11/2022]
Abstract
Proteomic characterization of alveolar bones in oral surgery represents an analytical challenge due to their insoluble character. The implementation of a straightforward technique could lead to the routine use of proteomics in this field. This work thus developed a simple technique for the characterization of bone tissue for human maxillary and mandibular bones. It is based on the direct in-bone tryptic digestion of proteins in both healthy and pathological human maxillary and mandibular bone samples. The released peptides were then identified by the LC-MS/MS. Using this approach, a total of 1120 proteins were identified in the maxillary bone and 1151 proteins in the mandibular bone. The subsequent partial least squares-discrimination analysis (PLS-DA) of protein data made it possible to reach 100% discrimination between the samples of healthy alveolar bones and those of the bone tissue surrounding the inflammatory focus. These results indicate that the in-bone protein digestion followed by the LC-MS/MS and subsequent statistical analysis can provide a deeper insight into the field of oral surgery at the molecular level. Furthermore, it could also have a diagnostic potential in the differentiation between the proteomic patterns of healthy and pathological alveolar bone tissue. Data are available via ProteomeXchange with the identifier PXD026775.
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Affiliation(s)
- Radovan Hynek
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, Prague 6, 166 28, Czech Republic
| | - Iva Michalus
- First Faculty of Medicine, Charles University, Kateřinská 32, Prague 2, 121 08, Czech Republic
| | - Pavel Cejnar
- Department of Computing and Control Engineering, University of Chemistry and Technology, Prague, Technická 5, Prague 6, 166 28, Czech Republic
| | - Jiří Šantrůček
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, Prague 6, 166 28, Czech Republic
| | - Sabina Seidlová
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, Prague 6, 166 28, Czech Republic
| | - Štěpánka Kučková
- Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 5, Prague 6, 166 28, Czech Republic
| | - Petra Sázelová
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo 542/2, Prague 6, 166 10, Czech Republic
| | - Václav Kašička
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo 542/2, Prague 6, 166 10, Czech Republic
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Nakamura HK, Butz F, Saruwatari L, Ogawa T. A Role for Proteoglycans in Mineralized Tissue-Titanium Adhesion. J Dent Res 2016; 86:147-52. [PMID: 17251514 DOI: 10.1177/154405910708600208] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Biomechanical properties of the bone-titanium interface have rarely been studied, due to the technical limitations involved; whether biological bonding mechanisms exist has not been determined. We hypothesized that a selected set of proteoglycan/glycosaminoglycan complexes plays a role in establishing the adhesion between bone and titanium, and utilized the rat bone-marrow-derived osteoblastic culture model to gain an insight into the hypothesis. Gene expression of selected proteoglycan core proteins was up-regulated in the osteoblasts cultured on titanium compared with those on polystyrene. Various sulfated glycosaminoglycans were immunochemically localized at mineralized tissue-titanium interfaces. The administration of various glycosaminoglycan-degrading enzymes into the cultures resulted in a 25–45% reduction of the tissue-titanium interfacial strength, measured by a nanoscratch test; while the hardness and elastic modulus of the mineralized tissue, evaluated by nano-indentation, were not altered. In conclusion, glycosaminoglycan degradation resulted in a decreased interfacial strength between cultured mineralized tissue and titanium, but did not alter the intrinsic strength of the mineralized tissue, suggesting a role for proteoglycan/glycosaminoglycan complexes in the establishment of tissue-titanium adhesion.
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Affiliation(s)
- H K Nakamura
- The Jane and Jerry Weintraub Center for Reconstructive Biotechnology, Division of Advanced Prosthodontics, Biomaterials and Hospital Dentistry, UCLA School of Dentistry, Los Angeles, California 90095-1668, USA
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Rucci N, Teti A. The "love-hate" relationship between osteoclasts and bone matrix. Matrix Biol 2016; 52-54:176-190. [PMID: 26921625 DOI: 10.1016/j.matbio.2016.02.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 02/22/2016] [Accepted: 02/22/2016] [Indexed: 01/06/2023]
Abstract
Osteoclasts are unique cells that destroy the mineralized matrix of the skeleton. There is a "love-hate" relationship between the osteoclasts and the bone matrix, whereby the osteoclast is stimulated by the contact with the matrix but, at the same time, it disrupts the matrix, which, in turn, counteracts this disruption by some of its components. The balance between these concerted events brings about bone resorption to be controlled and to contribute to bone tissue integrity and skeletal health. The matrix components released by osteoclasts are also involved in the local regulation of other bone cells and in the systemic control of organismal homeostasis. Disruption of this regulatory loop causes bone diseases, which may end up with either reduced or increased bone mass, often associated with poor bone quality. Expanding the knowledge on osteoclast-to-matrix interaction could help to counteract these diseases and improve the human bone health. In this article, we will present evidence of the physical, molecular and regulatory relationships between the osteoclasts and the mineralized matrix, discussing the underlying mechanisms as well as their pathologic alterations and potential targeting.
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Affiliation(s)
- Nadia Rucci
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy
| | - Anna Teti
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, Italy.
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Wattanachanya L, Wang L, Millard SM, Lu WD, O'Carroll D, Hsiao EC, Conklin BR, Nissenson RA. Assessing the osteoblast transcriptome in a model of enhanced bone formation due to constitutive Gs-G protein signaling in osteoblasts. Exp Cell Res 2015; 333:289-302. [PMID: 25704759 DOI: 10.1016/j.yexcr.2015.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 01/29/2015] [Accepted: 02/11/2015] [Indexed: 12/29/2022]
Abstract
G protein-coupled receptor (GPCR) signaling in osteoblasts (OBs) is an important regulator of bone formation. We previously described a mouse model expressing Rs1, an engineered constitutively active Gs-coupled GPCR, under the control of the 2.3 kb Col I promoter. These mice showed a dramatic age-dependent increase in trabecular bone of femurs. Here, we further evaluated the effects of enhanced Gs signaling in OBs on intramembranous bone formation by examining calvariae of 1- and 9-week-old Col1(2.3)/Rs1 mice and characterized the in vivo gene expression specifically occurring in osteoblasts with activated Gs G protein-coupled receptor signaling, at the cellular level rather than in a whole bone. Rs1 calvariae displayed a dramatic increase in bone volume with partial loss of cortical structure. By immunohistochemistry, Osterix was detected in cells throughout the inter-trabecular space while Osteocalcin was expressed predominantly in cells along bone surfaces, suggesting the role of paracrine mediators secreted from OBs driven by 2.3 kb Col I promoter could influence early OB commitment, differentiation, and/or proliferation. Gene expression analysis of calvarial OBs revealed that genes affected by Rs1 signaling include those encoding proteins important for cell differentiation, cytokines and growth factors, angiogenesis, coagulation, and energy metabolism. The set of Gs-GPCRs and other GPCRs that may contribute to the observed skeletal phenotype and candidate paracrine mediators of the effect of Gs signaling in OBs were also determined. Our results identify novel detailed in vivo cellular changes of the anabolic response of the skeleton to Gs signaling in mature OBs.
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Affiliation(s)
- Lalita Wattanachanya
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA; Division of Endocrinology and Metabolism, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand.
| | - Liping Wang
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA.
| | - Susan M Millard
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA.
| | - Wei-Dar Lu
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA.
| | - Dylan O'Carroll
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA.
| | - Edward C Hsiao
- Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Francisco, CA, USA.
| | - Bruce R Conklin
- Gladstone Institute of Cardiovascular Disease, San Francisco, CA, USA; Department of Medicine, University of California, San Francisco, CA, USA; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA, USA.
| | - Robert A Nissenson
- Endocrine Research Unit, Veterans Affairs Medical Center and Departments of Medicine and Physiology, University of California, San Francisco, CA, USA.
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Capulli M, Olstad OK, Onnerfjord P, Tillgren V, Muraca M, Gautvik KM, Heinegård D, Rucci N, Teti A. The C-terminal domain of chondroadherin: a new regulator of osteoclast motility counteracting bone loss. J Bone Miner Res 2014; 29:1833-46. [PMID: 24616121 DOI: 10.1002/jbmr.2206] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 01/23/2014] [Accepted: 02/06/2014] [Indexed: 11/12/2022]
Abstract
Chondroadherin (CHAD) is a leucine-rich protein promoting cell attachment through binding to integrin α2 β1 and syndecans. We observed that CHAD mRNA and protein were lower in bone biopsies of 50-year-old to 65-year-old osteoporotic women and in bone samples of ovariectomized mice versus gender/age-matched controls, suggesting a role in bone metabolism. By the means of an internal cyclic peptide (cyclicCHAD), we observed that its integrin binding sequence impaired preosteoclast migration through a nitric oxide synthase 2-dependent mechanism, decreasing osteoclastogenesis and bone resorption in a concentration-dependent fashion, whereas it had no effect on osteoblasts. Consistently, cyclicCHAD reduced transcription of two nitric oxide downstream genes, migfilin and vasp, involved in cell motility. Furthermore, the nitric oxide donor, S-nitroso-N-acetyl-D,L-penicillamine, stimulated preosteoclast migration and prevented the inhibitory effect of cyclicCHAD. Conversely, the nitric oxide synthase 2 (NOS2) inhibitor, N5-(1-iminoethyl)-l-ornithine, decreased both preosteoclast migration and differentiation, confirming a role of the nitric oxide pathway in the mechanism of action triggered by cyclicCHAD. In vivo, administration of cyclicCHAD was well tolerated and increased bone volume in healthy mice, with no adverse effect. In ovariectomized mice cyclicCHAD improved bone mass by both a preventive and a curative treatment protocol, with an effect in line with that of the bisphosphonate alendronate, that was mimicked by the NOS2 inhibitor [L-N6-(1-Iminoethyl)-lysine.2 dihydrochloride]. In both mouse models, cyclicCHAD reduced osteoclast and bone resorption without affecting osteoblast parameters and bone formation. In conclusion, CHAD is a novel regulator of bone metabolism that, through its integrin binding domain, inhibits preosteoclast motility and bone resorption, with a potential translational impact for the treatment of osteoporosis.
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Affiliation(s)
- Mattia Capulli
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
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Osteoblast and bone tissue response to surface modified zirconia and titanium implant materials. Dent Mater 2013; 29:763-76. [DOI: 10.1016/j.dental.2013.04.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 02/24/2013] [Accepted: 04/11/2013] [Indexed: 12/31/2022]
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Akhatib B, Önnerfjord P, Gawri R, Ouellet J, Jarzem P, Heinegård D, Mort J, Roughley P, Haglund L. Chondroadherin fragmentation mediated by the protease HTRA1 distinguishes human intervertebral disc degeneration from normal aging. J Biol Chem 2013; 288:19280-7. [PMID: 23673665 PMCID: PMC3696698 DOI: 10.1074/jbc.m112.443010] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 05/02/2013] [Indexed: 01/21/2023] Open
Abstract
Chondroadherin, a member of the leucine-rich repeat family, has previously been demonstrated to be fragmented in some juveniles with idiopathic scoliosis. This observation led us to investigate adults with disc degeneration. Immunoblotting analysis demonstrated that non-degenerate discs from three different age groups show no chondroadherin fragmentation. Furthermore, the chondroadherin fragments in adult degenerate disc and the juvenile scoliotic disc were compared via immunoblot analysis and appeared to have a similar size. We then investigated whether or not chondroadherin fragmentation increases with the severity of disc degeneration. Three different samples with different severities were chosen from the same disc, and chondroadherin fragmentation was found to be more abundant with increasing severity of degeneration. This observation led us to the creation of a neoepitope antibody to the cleavage site observed. We then observed that the cleavage site in adult degenerate discs and juvenile scoliotic discs was identical as confirmed by the neoepitope antibody. Consequently, investigation of the protease capable of cleaving chondroadherin at this site was necessary. In vitro digests of disc tissue demonstrated that ADAMTS-4 and -5; cathepsins K, B, and L; and MMP-3, -7, -12, and -13 were incapable of cleavage of chondroadherin at this site and that HTRA1 was indeed the only protease capable. Furthermore, increased protein levels of the processed form of HTRA1 were demonstrated in degenerate disc tissues via immunoblotting. The results suggest that chondroadherin fragmentation can be used as a biomarker to distinguish the processes of disc degeneration from normal aging.
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Affiliation(s)
- Bashar Akhatib
- From the Orthopaedic Research Laboratory, McGill University, Montreal, Quebec H3G 1A4, Canada
| | - Patrik Önnerfjord
- Department of Clinical Sciences, Lund Section for Rheumatology, Molecular Skeletal Biology, Biomedical Center C12, Lund University, SE-22184 Lund, Sweden
| | - Rahul Gawri
- From the Orthopaedic Research Laboratory, McGill University, Montreal, Quebec H3G 1A4, Canada
| | - Jean Ouellet
- Department of Clinical Sciences, Lund Section for Rheumatology, Molecular Skeletal Biology, Biomedical Center C12, Lund University, SE-22184 Lund, Sweden
- McGill Scoliosis and Spine Group, Montreal, Quebec H3A 1A1, Canada, and
| | - Peter Jarzem
- Department of Clinical Sciences, Lund Section for Rheumatology, Molecular Skeletal Biology, Biomedical Center C12, Lund University, SE-22184 Lund, Sweden
- McGill Scoliosis and Spine Group, Montreal, Quebec H3A 1A1, Canada, and
| | - Dick Heinegård
- Department of Clinical Sciences, Lund Section for Rheumatology, Molecular Skeletal Biology, Biomedical Center C12, Lund University, SE-22184 Lund, Sweden
| | - John Mort
- Genetics Unit, Shriners Hospitals for Children, Montreal, Quebec H3G 1A6, Canada
| | - Peter Roughley
- Genetics Unit, Shriners Hospitals for Children, Montreal, Quebec H3G 1A6, Canada
| | - Lisbet Haglund
- From the Orthopaedic Research Laboratory, McGill University, Montreal, Quebec H3G 1A4, Canada
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Hessle L, Stordalen GA, Wenglén C, Petzold C, Tanner EK, Brorson SH, Baekkevold ES, Önnerfjord P, Reinholt FP, Heinegård D. The skeletal phenotype of chondroadherin deficient mice. PLoS One 2013; 8:e63080. [PMID: 23755099 PMCID: PMC3670915 DOI: 10.1371/journal.pone.0063080] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 03/24/2013] [Indexed: 11/27/2022] Open
Abstract
Chondroadherin, a leucine rich repeat extracellular matrix protein with functions in cell to matrix interactions, binds cells via their α2β1 integrin as well as via cell surface proteoglycans, providing for different sets of signals to the cell. Additionally, the protein acts as an anchor to the matrix by binding tightly to collagens type I and II as well as type VI. We generated mice with inactivated chondroadherin gene to provide integrated studies of the role of the protein. The null mice presented distinct phenotypes with affected cartilage as well as bone. At 3–6 weeks of age the epiphyseal growth plate was widened most pronounced in the proliferative zone. The proteome of the femoral head articular cartilage at 4 months of age showed some distinct differences, with increased deposition of cartilage intermediate layer protein 1 and fibronectin in the chondroadherin deficient mice, more pronounced in the female. Other proteins show decreased levels in the deficient mice, particularly pronounced for matrilin-1, thrombospondin-1 and notably the members of the α1-antitrypsin family of proteinase inhibitors as well as for a member of the bone morphogenetic protein growth factor family. Thus, cartilage homeostasis is distinctly altered. The bone phenotype was expressed in several ways. The number of bone sialoprotein mRNA expressing cells in the proximal tibial metaphysic was decreased and the osteoid surface was increased possibly indicating a change in mineral metabolism. Micro-CT revealed lower cortical thickness and increased structure model index, i.e. the amount of plates and rods composing the bone trabeculas. The structural changes were paralleled by loss of function, where the null mice showed lower femoral neck failure load and tibial strength during mechanical testing at 4 months of age. The skeletal phenotype points at a role for chondroadherin in both bone and cartilage homeostasis, however, without leading to altered longitudinal growth.
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Affiliation(s)
- Lovisa Hessle
- Sections of Molecular Skeletal Biology and Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Gunhild A. Stordalen
- Department of Pathology, University of Oslo, and Oslo University Hospital, Rikshospitalet, Oslo, Norway
- * E-mail:
| | - Christina Wenglén
- Sections of Molecular Skeletal Biology and Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | | | - Elizabeth K. Tanner
- School of Engineering, University of Glasgow, Glasgow, United Kingdom
- Section of Orthopaedics, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Sverre-Henning Brorson
- Department of Pathology, University of Oslo, and Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Espen S. Baekkevold
- Department of Pathology, University of Oslo, and Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Patrik Önnerfjord
- Sections of Molecular Skeletal Biology and Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Finn P. Reinholt
- Department of Pathology, University of Oslo, and Oslo University Hospital, Rikshospitalet, Oslo, Norway
| | - Dick Heinegård
- Sections of Molecular Skeletal Biology and Rheumatology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
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Genes involved in systemic and arterial bed dependent atherosclerosis--Tampere Vascular study. PLoS One 2012; 7:e33787. [PMID: 22509262 PMCID: PMC3324479 DOI: 10.1371/journal.pone.0033787] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 02/19/2012] [Indexed: 12/23/2022] Open
Abstract
Background Atherosclerosis is a complex disease with hundreds of genes influencing its progression. In addition, the phenotype of the disease varies significantly depending on the arterial bed. Methodology/Principal Findings We characterized the genes generally involved in human advanced atherosclerotic (AHA type V–VI) plaques in carotid and femoral arteries as well as aortas from 24 subjects of Tampere Vascular study and compared the results to non-atherosclerotic internal thoracic arteries (n=6) using genome-wide expression array and QRT-PCR. In addition we determined genes that were typical for each arterial plaque studied. To gain a comprehensive insight into the pathologic processes in the plaques we also analyzed pathways and gene sets dysregulated in this disease using gene set enrichment analysis (GSEA). According to the selection criteria used (>3.0 fold change and p-value <0.05), 235 genes were up-regulated and 68 genes down-regulated in the carotid plaques, 242 genes up-regulated and 116 down-regulated in the femoral plaques and 256 genes up-regulated and 49 genes down-regulated in the aortic plaques. Nine genes were found to be specifically induced predominantly in aortic plaques, e.g., lactoferrin, and three genes in femoral plaques, e.g., chondroadherin, whereas no gene was found to be specific for carotid plaques. In pathway analysis, a total of 28 pathways or gene sets were found to be significantly dysregulated in atherosclerotic plaques (false discovery rate [FDR] <0.25). Conclusions This study describes comprehensively the gene expression changes that generally prevail in human atherosclerotic plaques. In addition, site specific genes induced only in femoral or aortic plaques were found, reflecting that atherosclerotic process has unique features in different vascular beds.
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Gao Y, Feng CG, Song C, Du ZQ, Deng XM, Li N, Hu XX. Mapping quantitative trait loci affecting chicken body size traits via genome scanning. Anim Genet 2011; 42:670-4. [DOI: 10.1111/j.1365-2052.2011.02193.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Jim B, Steffen T, Moir J, Roughley P, Haglund L. Development of an intact intervertebral disc organ culture system in which degeneration can be induced as a prelude to studying repair potential. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2011; 20:1244-54. [PMID: 21336509 DOI: 10.1007/s00586-011-1721-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2010] [Revised: 12/28/2010] [Accepted: 02/06/2011] [Indexed: 01/08/2023]
Abstract
The present work describes a novel bovine disc organ culture system with long-term maintenance of cell viability, in which degenerative changes can be induced as a prelude to studying repair. Discs were isolated with three different techniques: without endplates (NEP), with bony endplates (BEP) and with intact cartilage endplates (CEP). Swelling, deformation, and cell viability were evaluated in unloaded cultures. Degeneration was induced by a single trypsin injection into the center of the disc and the effect on cell viability and matrix degradation was followed. Trypsin-treated discs were exposed to TGFβ to evaluate the potential to study repair in this system. NEP isolated discs showed >75% maintained cell viability for up to 10 days but were severely deformed, BEP discs on the other hand maintained morphology but failed to retain cell viability having only 27% viable cells after 10 days. In CEP discs, both cell viability and morphology were maintained for at least 4 weeks where >75% of the cells were still viable. To mimic proteoglycan loss during disc degeneration, a single trypsin injection was administered to the center of the disc. This resulted in 60% loss of aggrecan, after 7 days, without affecting cell viability. When TGFβ was injected to validate that the system can be used to study a repair response following injection of a bio-active substance, proteoglycan synthesis nearly doubled compared to baseline synthesis. Trypsin-treated bovine CEP discs therefore provide a model system for studying repair of the degenerate disc, as morphology, cell viability and responsiveness to bio-active substances were maintained.
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Affiliation(s)
- Bernice Jim
- Orthopaedic Research Laboratory, McGill University, 687 Pine Avenue West, Room L4.70, Montreal, QC H3A 1A1, Canada
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Abstract
STUDY DESIGN Variation in abundance and structure of chondroadherin (CHAD) were studied in the extracellular matrix (ECM) of scoliotic and normal human discs. OBJECTIVE To determine whether CHAD abundance and fragmentation vary between different sides of the scoliotic disc and between scoliotic and normal discs. SUMMARY OF BACKGROUND DATA Scoliosis involves curvature of the spine including wedging of the intervertebral discs (IVDs), resulting in altered mechanical loading, which can influence cell metabolism and matrix structure in the IVD. A protein such as CHAD that can influence both cell metabolism and ECM organization could influence disc pathology in scoliosis. METHODS IVDs were obtained from patients with scoliosis and from normal individuals. A proteomic analysis was performed to identify molecules that exhibit side-specific variations in abundance. In addition, changes in the abundance and fragmentation of CHAD and other members of the leucine-rich repeat protein family were studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. Aggrecan fragmentation was used as an indicator of proteinase action. RESULTS The relative amount of CHAD was consistently lower on the concave side of the discs in all patients studied. In addition, proteolytic degradation of CHAD occurred in some patients with scoliosis, but not in normal IVDs. The presence of aggrecan fragments provided evidence for both aggrecanase and metalloproteinase activity in the scoliotic discs although no side-specific difference was found. Other members of the leucine-rich repeat family of proteins did not show evidence of the same consistent variation in abundance between the 2 sides and did not show signs of degradation. CONCLUSION As CHAD can interact with both the ECM and the cells, it can provide a mechanism for regulating cell metabolism and ECM structure, and so play a role in promoting matrix homeostasis. Thus, changes in CHAD abundance or structure could be associated with the pathologic changes occurring in the scoliotic IVD.
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Kojima N, Ozawa S, Miyata Y, Hasegawa H, Tanaka Y, Ogawa T. High-throughput gene expression analysis in bone healing around titanium implants by DNA microarray. Clin Oral Implants Res 2008; 19:173-81. [PMID: 18184341 DOI: 10.1111/j.1600-0501.2007.01432.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Bone generation occurs around titanium implants; however, its underlying mechanisms are relatively unknown. We attempt to identify gene transcripts specifically upregulated in in vivo bone healing with titanium implants using DNA microarray. MATERIAL AND METHODS Titanium implants were placed into rat femurs, and total RNA was extracted from the implant-associated tissue at weeks 1, 2 and 4 of healing. As a control, RNA was extracted from the tissue undergoing osteotomy healing. The RNA samples were hybridized onto oligo DNA microarray. RESULTS Most of the 20,000 genes tested were expressed similarly in both the implant- and osteotomy-healing groups. Eighty-six genes were upregulated (>2-fold) in the implant-healing group compared with the osteotomy-healing group in at least one time point of healing. Twelve genes were upregulated in the implant healing at week 2 and earlier, while 31 genes were upregulated at week 2 and later. Only one gene was upregulated specifically at week 1, while three genes were consistently upregulated from weeks 1 to 4. The upregulated genes included collagenous and non-collagenous extracellular matrix (ECM)-related genes, proteoglycans and bone resorption-related genes. Pathway analysis revealed the involvement of ECM and receptor interaction in implant healing. CONCLUSIONS This study provides evidence that a set of gene transcripts is upregulated in the implant healing over the osteotomy healing, which seems to represent the coordinated biological events of long-lasting osteogenesis and bone remodeling required for osseointegration. Further studies are needed to identify the significance and biological roles of the transcripts in osseointegration. Proven reliability and usefulness of microarray technology should encourage future approaches to develop a high-throughput molecular assessment for osseointegration capacity of new implant surfaces.
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Affiliation(s)
- Norinaga Kojima
- Department of Prosthodontics, Aichi-Gakuin University School of Dentistry, Nagoya, Japan
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15
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Rorive S, Maris C, Debeir O, Sandras F, Vidaud M, Bièche I, Salmon I, Decaestecker C. Exploring the Distinctive Biological Characteristics of Pilocytic and Low-Grade Diffuse Astrocytomas Using Microarray Gene Expression Profiles. J Neuropathol Exp Neurol 2006; 65:794-807. [PMID: 16896313 DOI: 10.1097/01.jnen.0000228203.12292.a1] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Although World Health Organization (WHO) grade I pilocytic astrocytomas and grade II diffuse astrocytomas have been classified for decades as different clinicopathologic entities, few, if any, data are available on the biologic features explaining these differences. Although more than 50 microarray-related studies have been carried out to characterize the molecular profiles of astrocytic tumors, we have identified only 11 that provide sound data on low-grade astrocytomas. We have incorporated these data into a comparative analysis for the purpose of identifying the most relevant molecular markers characterizing grade I pilocytic and grade II diffuse astrocytomas. Our analysis has identified various interesting genes that are differentially expressed in either grade I or grade II astrocytomas when compared with normal tissue and/or high-grade (WHO grade III and IV) astrocytomas. A large majority of these genes encode adhesion, extracellular matrix, and invasion-related proteins. Interestingly, a group of 6 genes (TIMP4, C1NH, CHAD, THBS4, IGFBP2, and TLE2) constitute an expression profile characteristic of grade I astrocytomas as compared with all other categories of tissue (normal brain, grade II, and high-grade astrocytomas). The end products (proteins) of these genes act as antimigratory compounds, a fact that could explain why pilocytic astrocytomas behave as compact (well-circumscribed) tumors as opposed to all the other astrocytic tumor types that diffusely invade the brain parenchyma. Having validated these molecular markers by means of real-time reverse transcriptase-polymerase chain reaction, an integrated model was proposed illustrating how and why pilocytic astrocytomas constitute a distinct biologic and pathologic entity when compared with diffuse astrocytomas.
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Affiliation(s)
- Sandrine Rorive
- Laboratory of Pathology, Erasmus University Hospital, The Netherlands
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16
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Ichikawa T, Horie-Inoue K, Ikeda K, Blumberg B, Inoue S. Steroid and xenobiotic receptor SXR mediates vitamin K2-activated transcription of extracellular matrix-related genes and collagen accumulation in osteoblastic cells. J Biol Chem 2006; 281:16927-16934. [PMID: 16606623 DOI: 10.1074/jbc.m600896200] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vitamin K2 is a critical nutrient required for blood coagulation. It also plays a key role in bone homeostasis and is a clinically effective therapeutic agent for osteoporosis. We previously demonstrated that vitamin K2 is a transcriptional regulator of bone marker genes in osteoblastic cells and that it may potentiate bone formation by activating the steroid and xenobiotic receptor, SXR. To explore the SXR-mediated vitamin K2 signaling network in bone homeostasis, we identified genes up-regulated by both vitamin K2 and the prototypical SXR ligand, rifampicin, in osteoblastic cells using oligonucleotide microarray analysis and quantitative reverse transcription-PCR. Fourteen genes were up-regulated by both ligands. Among these, tsukushi, matrilin-2, and CD14 antigen were shown to be primary SXR target genes. Moreover, collagen accumulation in osteoblastic MG63 cells was enhanced by vitamin K2 treatment. Gain- and loss-of-function analyses showed that the small leucine-rich proteoglycan, tsukushi, contributes to vitamin K2-mediated enhancement of collagen accumulation. Our results suggest a new function for vitamin K2 in bone formation as a transcriptional regulator of extracellular matrix-related genes, that are involved in the collagen assembly.
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Affiliation(s)
- Tomoe Ichikawa
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical School, Saitama 350-1241, Japan
| | - Kuniko Horie-Inoue
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical School, Saitama 350-1241, Japan
| | - Kazuhiro Ikeda
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical School, Saitama 350-1241, Japan
| | - Bruce Blumberg
- Department of Developmental and Cell Biology, University of California, Irvine, California 92697-2300
| | - Satoshi Inoue
- Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical School, Saitama 350-1241, Japan; Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-8655, Japan.
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17
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Nakamura H, Shim J, Butz F, Aita H, Gupta V, Ogawa T. Glycosaminoglycan degradation reduces mineralized tissue–titanium interfacial strength. J Biomed Mater Res A 2006; 77:478-86. [PMID: 16482547 DOI: 10.1002/jbm.a.30624] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Although the localization of the proteoglycan/glycosaminoglycan (GAG) complex at the bone-titanium implant interface has been implied, the role of proteoglycans on the establishment of bone-titanium integration is unknown. The hypothesis to be tested was that proteoglycans play an important role in establishing bone-titanium interfacial adhesion. The objective of this study is to investigate the effect of proteoglycan knockdown by GAG enzymatic degradation on the interfacial strength between mineralized tissue and titanium having different surface topographies. Rat bone marrow-derived osteoblastic cells were cultured on either a machined titanium disk or an acid-etched titanium disk. At day 21 of culture, one of the three following GAG degradation enzymes was added into the culture; chondroitinase AC, chondroitinase B, or keratanase. After 3 days of incubation (at day 24 of culture), the laser spallation technique was applied to the samples in order to assess the tissue-titanium interfacial strength. In this technique, a laser-generated stress wave is used to separate the tissue-titanium interface, and the interfacial strength is determined interferometrically by recording the transient free surface velocity of the tissue. Mineralized tissue cultured on the acid-etched titanium showed 20-30% higher tissue interfacial strength than that cultured on the machined titanium (p < 0.0001). For both the machined and acid-etched surface cultures, administration of the enzyme reduced the interfacial strength by 25-30% compared with the untreated control cultures (p < 0.0001). There were no differences in the effect among the three different enzymes tested. A nanoindentation study revealed that the enzyme treatment did not affect the elastic modulus of the mineralized tissue. Scanning electron microscopic and energy dispersive spectroscopic analyses revealed less post-spallation tissue remnant on the titanium substrates when treated with the enzymes. The tissue remnant was greater in amount on the acid-etched surface than on the machined surface. The results suggest that there exists not only mechanical interlocking but also biological interfacial adhesion between the mineralized tissue and titanium, in which the proteoglycan/GAG complex is involved.
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Affiliation(s)
- Hiromi Nakamura
- The Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, California 90095-1668, USA
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18
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Heiner DE, Meyer MH, Frick SL, Kellam JF, Fiechtl J, Meyer RA. Gene expression during fracture healing in rats comparing intramedullary fixation to plate fixation by DNA microarray. J Orthop Trauma 2006; 20:27-38. [PMID: 16424807 DOI: 10.1097/01.bot.0000184143.90448.aa] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE This study was designed to compare mRNA gene expression in healing diaphyseal femoral fractures between those injuries treated with intramedullary nails and those treated with internal plate fixation. DESIGN RNA gene expression was measured at 1 day, 3 days, and 1, 2, 4, and 6 weeks after surgery in the fracture callus of rats randomized to femoral shaft fracture with intramedullary nail fixation, rigid plate fixation, or sham fracture. SETTING AAALAC-accredited vivarium of an independent academic medical center. ANIMALS Fifty-seven, adult, female, Sprague-Dawley rats at 16 weeks of age. INTERVENTION Femoral fracture with intramedullary nail fixation, femoral fracture with plate and screw fixation, or sham surgery with no fracture. MAIN OUTCOME MEASUREMENTS RNA expression for 8700 genes was measured with 19 Affymetrix U34A microarrays. The fracture callus was significantly larger with intramedullary nail fixation than with plate fixation. Most genes responded to fracture with a change in mRNA expression. Most of the responding genes followed the same time course for both fixation methods. This included genes related to growth factors, bone matrix, mast cells, most nerve factors, and hematopoiesis. The intramedullary nail group had significantly greater up-regulation for transcripts related to cartilage, cell division, inflammation, and the acetylcholine receptor. There was significantly greater up-regulation in the plate group for genes related to macrophage activity. CONCLUSIONS There were differentially expressed genes present between the 2 surgical groups that may give insight into the control of fracture repair.
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Affiliation(s)
- Daniel E Heiner
- Department of Orthopaedic Surgery, Carolinas Medical Center, Charlotte, NC 28232-2861, USA
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19
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Wang W, Yang Y, Li L, Shi Y. Synleurin, a novel leucine-rich repeat protein that increases the intensity of pleiotropic cytokine responses. Biochem Biophys Res Commun 2003; 305:981-8. [PMID: 12767927 DOI: 10.1016/s0006-291x(03)00876-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have identified and characterized a novel single span transmembrane leucine-rich repeat protein, synleurin, that renders cells highly sensitive to the activation by cytokines and lipopolysaccharide (LPS). The major part of the extracellular domain consists of a leucine-rich repeats (LRR) cassette. The LRR central core has 12 analogous LRR repeating modules arranged in a seamless tandem array. The LRRs are most homologous to that of chondroadherin, insulin-like growth factor binding proteins, platelet glycoprotein V, slits, and toll-like receptors. Synleurin expression was detected at low levels in many tissues, including smooth muscle, brain, uterus, pancreas, cartilage, adipose, spleen, and testis. When synleurin is ecotopically expressed in transfected cells, the cells exhibit amplified responses to bFGF, EGF, PDGF-B, IGF-1, IGF-2, and LPS. Synleurin gene (slrn) maps to human chromosome at 5q12. The name synleurin reflects its synergistic effect on cytokine stimulation and its prominent leucine-rich repeats.
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Affiliation(s)
- Wei Wang
- Human Genome Sciences, Inc., 9410 Key West Avenue, Rockville, MD 20850, USA
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20
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Barry F, Boynton RE, Liu B, Murphy JM. Chondrogenic differentiation of mesenchymal stem cells from bone marrow: differentiation-dependent gene expression of matrix components. Exp Cell Res 2001; 268:189-200. [PMID: 11478845 DOI: 10.1006/excr.2001.5278] [Citation(s) in RCA: 689] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Transforming growth factor (TGF)-beta-induced chondrogenesis of mesenchymal stem cells derived from bone marrow involves the rapid deposition of a cartilage-specific extracellular matrix. The sequential events in this pathway leading from the undifferentiated stem cell to a mature chondrocyte were investigated by analysis of key matrix elements. Differentiation was rapidly induced in cells cultured in the presence of TGF-beta 3 or -beta 2 and was accompanied by the early expression of fibromodulin and cartilage oligomeric matrix protein. An increase in aggrecan and versican core protein synthesis defined an intermediate stage, which also involved the small leucine-rich proteoglycans decorin and biglycan. This was followed by the appearance of type II collagen and chondroadherin. The pathway was also characterized by the appearance of type X collagen, usually associated with hypertrophic cartilage. There was also a change in the pattern of sulfation of chondroitin sulfate, with a progressive increase in the proportion of 6-sulfated species. The major proportion of newly synthesized glycosaminoglycan was part of an aggregating proteoglycan network. These data allow us to define the phenotype of the differentiated cell and to understand in greater detail the sequential process of matrix assembly.
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Affiliation(s)
- F Barry
- Osiris Therapeutics, Inc., 2001 Aliceanna Street, Baltimore, Maryland 21231, USA.
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21
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Koller DL, Liu G, Econs MJ, Hui SL, Morin PA, Joslyn G, Rodriguez LA, Conneally PM, Christian JC, Johnston CC, Foroud T, Peacock M. Genome screen for quantitative trait loci underlying normal variation in femoral structure. J Bone Miner Res 2001; 16:985-91. [PMID: 11393795 DOI: 10.1359/jbmr.2001.16.6.985] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Femoral structure contributes to bone strength at the proximal femur and predicts hip fracture risk independently of bone mass. Quantitative components of femoral structure are highly heritable traits. To identify genetic loci underlying variation in these structural phenotypes, we conducted an autosomal genome screen in 309 white sister pairs. Seven structural variables were measured from femoral radiographs and used in multipoint sib-pair linkage analyses. Three chromosomal regions were identified with significant evidence of linkage (log10 of the odds ratio [LOD] > 3.6) to at least one femoral structure phenotype. The maximum LOD score of 4.3 was obtained for femur neck axis length on chromosome 5q. Evidence of linkage to chromosome 4q was found with both femur neck axis length (LOD = 3.9) and midfemur width (LOD = 3.5). Significant evidence of linkage also was found to chromosome 17q, with a LOD score of 3.6 for femur head width. Two additional chromosomal regions 3q and 19p gave suggestive (LOD > 2.2) evidence of linkage with at least two of the structure phenotypes. Chromosome 3 showed evidence of linkage with pelvic axis length (LOD = 3.1), midfemur width (LOD = 2.8), and femur head width (LOD = 2.3), spanning a broad (60 cm) region of chromosome 3q. Linkage to chromosome 19 was supported by two phenotypes, femur neck axis length (LOD = 2.8) and femur head width (LOD = 2.8). This study is the first genome screen for loci underlying variation in femoral structure and represents an important step toward identifying genes contributing to the risk of osteoporotic hip fracture in the general population.
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Affiliation(s)
- D L Koller
- Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis 46202, USA
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22
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Shen Z, Gantcheva S, Mânsson B, Heinegârd D, Sommarin Y. Chondroadherin expression changes in skeletal development. Biochem J 1998; 330 ( Pt 1):549-57. [PMID: 9461555 PMCID: PMC1219172 DOI: 10.1042/bj3300549] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Chondroadherin is a cartilage protein with cell binding properties. The expression of chondroadherin was studied in rat tissues and during postnatal femoral head development. For design of oligonucleotide probes and primers a 1664 bp, full length, rat chondroadherin cDNA was isolated from a rat chondrosarcoma library and sequenced. Northern blot analysis showed chondroadherin mRNA to be present in femoral head and rib cartilage, as well as in tendon. More sensitive reverse-transcriptase PCR additionally identified the mRNA in calvaria, long bone and bone marrow. Localization of chondroadherin by immunocytochemistry in the developing femoral head from postnatal day 14 to day 60 showed presence of the protein in cartilaginous regions. With increasing age a very distinct localization of chondroadherin was seen in the territorial matrix around late proliferative cells in the growth plate as well as in the developing articular cartilage in the maturing femoral head. Localization of chondroadherin mRNA by in situ hybridization was in agreement with immunocytochemistry with strong hybridization signals in late proliferative cells in the growth plate. In the articular cartilage the expression was restricted to cells in the lower regions. A three-fold increase of cartilage chondroadherin content in the growing femoral head was demonstrated by Western blot analysis. The high expression of this cell binding protein in a dynamic region of cartilage suggests an important role for chondroadherin in the regulation of chondrocyte growth and proliferation.
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Affiliation(s)
- Z Shen
- Section for Connective Tissue Biology, Department of Cell and Molecular Biology, University of Lund, Lund, Sweden
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