1
|
Mohanakrishnan V, Balasubramanian A, Mahalingam G, Partridge NC, Ramachandran I, Selvamurugan N. Parathyroid hormone-induced down-regulation of miR-532-5p for matrix metalloproteinase-13 expression in rat osteoblasts. J Cell Biochem 2018; 119:6181-6193. [PMID: 29626351 DOI: 10.1002/jcb.26827] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 02/28/2018] [Indexed: 12/14/2022]
Abstract
Parathyroid hormone (PTH) acts on osteoblasts and functions as an essential regulator of calcium homeostasis and as a mediator of bone remodeling. We previously reported that PTH stimulates the expression of matrix metalloproteinase-13 (MMP-13) in rat osteoblasts and that MMP-13 plays a key role in bone remodeling, endochondral bone formation, and bone repair. Recent evidence indicated that microRNAs (miRNAs) have regulatory functions in bone metabolism. In this study, we hypothesized that the down-regulation of miRNAs that target MMP-13 by PTH leads to the stimulation of MMP-13 expression in osteoblasts. We used various bioinformatic tools to identify miRNAs that putatively target rat MMP-13. Among these miRNAs, the expression of miR-532-5p in rat osteoblasts decreased at 4 h of PTH-treatment, whereas MMP-13 mRNA expression was maximal at the same time point. When an miR-532-5p mimic was transiently transfected into UMR-106-01 cells, MMP-13 mRNA and protein expression decreased. Using a luciferase reporter assay system, we also identified that miR-532-5p directly targeted the 3' UTRs of MMP-13 gene. Based on these results, we suggest that PTH-induced down-regulation of miR-532-5p resulted in the stimulation of MMP-13 expression in rat osteoblasts. This study identified a significant role of miRNA in controlling bone remodeling via PTH-stimulated MMP-13 expression. This finding enhances our understanding of bone metabolism and bone-related diseases and it could provide information regarding the usage of miRNAs as therapeutic agents or biomarkers.
Collapse
Affiliation(s)
- Vishal Mohanakrishnan
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Arumugam Balasubramanian
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Gokulnath Mahalingam
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| | - Nicola Chennell Partridge
- Department of Basic Science and Craniofacial Biology, New York University College of Dentistry, New York University, New York
| | - Ilangovan Ramachandran
- Department of Endocrinology, Dr. A.L.M. PG Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai, Tamil Nadu, India
| | - Nagarajan Selvamurugan
- Department of Biotechnology, School of Bioengineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, India
| |
Collapse
|
2
|
Matrix metalloproteinase-13: A special focus on its regulation by signaling cascades and microRNAs in bone. Int J Biol Macromol 2018; 109:338-349. [DOI: 10.1016/j.ijbiomac.2017.12.091] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 12/15/2017] [Accepted: 12/17/2017] [Indexed: 01/03/2023]
|
3
|
Arumugam B, Vairamani M, Partridge NC, Selvamurugan N. Characterization of Runx2 phosphorylation sites required for TGF‐β1‐mediated stimulation of matrix metalloproteinase‐13 expression in osteoblastic cells. J Cell Physiol 2017; 233:1082-1094. [DOI: 10.1002/jcp.25964] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 04/14/2017] [Indexed: 12/13/2022]
Affiliation(s)
| | - Mariappanadar Vairamani
- Department of BiotechnologySchool of BioengineeringSRM UniversityKattankulathurTamil NaduIndia
| | - Nicola C. Partridge
- Department of Basic Science and Craniofacial BiologyNew York University College of Dentistry, New York UniversityNew YorkNew York
| | - Nagarajan Selvamurugan
- Department of BiotechnologySchool of BioengineeringSRM UniversityKattankulathurTamil NaduIndia
| |
Collapse
|
4
|
Cytokine and Growth Factor mRNA Expression Patterns Associated with the Hypercontracted, Hyperpigmented Healing Phenotype of Red Duroc Pigs: A Model of Abnormal Human Scar Development? J Cutan Med Surg 2016. [DOI: 10.1177/120347540500900403] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Background: Skin wounds in red Duroc pigs heal with the formation of hypercontractile, hyperpigmented scars, similar in some respects to human hypertrophic scars. ObjectiveThe goal of this study was to characterize the mRNA expression patterns for a subset of relevant cytokines, growth factors, receptors, and transcription factors involved in the red Duroc scarring phenotype. Methods: Full-thickness and deep dermal wounds were created on the backs of juvenile female red Duroc pigs. Samples were taken every two weeks postwounding and total RNA and DNA were extracted and quantified. RT-PCR was performed using porcine gene-specific primers for 15 relevant molecules. Results: The majority of molecules examined exhibited a biphasic pattern of expression, with peaks of expression at days 14 and 56 postinjury. Conclusions: The molecular expression pattern observed correlates well with the gross healing phenotype and matrix molecule expression patterns previously reported in red Duroc pigs. These findings enhance our understanding of the processes associated with fibroproliferative scar-formation.
Collapse
|
5
|
The Molecular and Cellular Events That Take Place during Craniofacial Distraction Osteogenesis. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2014; 2:e98. [PMID: 25289295 PMCID: PMC4174219 DOI: 10.1097/gox.0000000000000043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 12/04/2013] [Indexed: 12/26/2022]
Abstract
Summary: Gradual bone lengthening using distraction osteogenesis principles is the gold standard for the treatment of hypoplastic facial bones. However, the long treatment time is a major disadvantage of the lengthening procedures. The aim of this study is to review the current literature and summarize the cellular and molecular events occurring during membranous craniofacial distraction osteogenesis. Mechanical stimulation by distraction induces biological responses of skeletal regeneration that is accomplished by a cascade of biological processes that may include differentiation of pluripotential tissue, angiogenesis, osteogenesis, mineralization, and remodeling. There are complex interactions between bone-forming osteoblasts and other cells present within the bone microenvironment, particularly vascular endothelial cells that may be pivotal members of a complex interactive communication network in bone. Studies have implicated number of cytokines that are intimately involved in the regulation of bone synthesis and turnover. The gene regulation of numerous cytokines (transforming growth factor-β, bone morphogenetic proteins, insulin-like growth factor-1, and fibroblast growth factor-2) and extracellular matrix proteins (osteonectin, osteopontin) during distraction osteogenesis has been best characterized and discussed. Understanding the biomolecular mechanisms that mediate membranous distraction osteogenesis may guide the development of targeted strategies designed to improve distraction osteogenesis and accelerate bone regeneration that may lead to shorten the treatment duration.
Collapse
|
6
|
Abstract
Oxidative stress is claimed to be a major cause of aging. Recent data suggest that calorie restriction (CR) prolongs life span by its ability to retard aging, possibly by regulating the intracellular redox status through its antioxidative actions. Currently, there is little information showing the influences of age and CR on the redox-sensitive transcription factor activator protein-1 (AP-1). In the present study, we investigated how age affects the status of AP-1 and whether CR modulates the age effect. For our study, we used the kidney from male Fischer 344 rats, ages 6, 12, 18, and 24 months fed ad libitum (AL) or a CR diet. Results from our study showed that AP-1 binding activity markedly increases with age, while CR keeps this activity at the level of 6-month-old rats. We found that c-Jun and c-Fos protein levels increase during aging, and that aging induces phosphorylation of c-Jun, which might enhance AP-1 transcriptional activity. For CR's action, we found that in the nucleus of aged rats, AP-1 activation was blunted by decreasing c-Jun and c-Fos levels and inhibiting c-Jun protein phosphorylation. Results also indicated that matrix metalloproteinase-13 and heme oxygenase-1, which have an AP-1 binding site in their promoter regions, have a similar tendency toward AP-1 binding activity. Based on the data of these findings, we concluded that AP-1 activity increases in rat kidney with age and that CR reduces AP-1 activity.
Collapse
|
7
|
Requirement for store-operated calcium entry in sodium butyrate-induced apoptosis in human colon cancer cells. Biosci Rep 2012; 32:83-90. [PMID: 21699495 DOI: 10.1042/bsr20110062] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The SOCE (store-operated Ca2+ entry) pathway plays a key role in both normal cells and cancerous cells. However, its molecular mechanism remains a long-lasting puzzle of Ca2+ signalling. In this paper, we provide evidence that butyric acid, a dietary fibre-derived short-chain fatty acid, induces apoptosis of colon cancer cells via SOCE signalling networks. We found that sodium butyrate (NaB) induces Ca2+ release from endoplasmic reticulum, which in turn causes extracellular Ca2+ influx in HCT-116 cells. The Ca2+ release and influx are important, because the addition of chelators, EGTA or BAPTA/AM [1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid tetrakis(acetoxymethyl ester)] respectively blocked NaB-induced apoptosis. Furthermore, down-regulation of STIM1 (stromal interaction molecule 1) by RNA interference or pharmacological blockade of the SOCC (store-operated Ca2+ channel) by 2-APB (2-aminoethoxydiphenyl borate) or SKF-96365 inhibited NaB-induced extracellular Ca2+ influx and apoptosis in HCT-116 cells. Thus we conclude that NaB triggers colon cancer cell apoptosis in an SOCE-dependent manner. This finding provides new insights into how butyric acid suppresses colon carcinogenesis.
Collapse
|
8
|
Mata-Greenwood E, Liao WX, Wang W, Zheng J, Chen DB. Activation of AP-1 transcription factors differentiates FGF2 and vascular endothelial growth factor regulation of endothelial nitric-oxide synthase expression in placental artery endothelial cells. J Biol Chem 2010; 285:17348-58. [PMID: 20371606 DOI: 10.1074/jbc.m109.092791] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
FGF2 (fibroblast growth factor 2), but not vascular endothelial growth factor (VEGF), stimulates sustained activation of ERK2/1 for endothelial NOS3 (nitric-oxide synthase 3) protein expression in ovine fetoplacental artery endothelial cells (oFPAEC). We deciphered herein the downstream signaling of ERK2/1 responsible for NOS3 expression by FGF2 in oFPAEC. FGF2, but not VEGF, increased NOS3 mRNA levels without altering its degradation. FGF2, but not VEGF, trans-activated sheep NOS3 promoter, and this was dependent on ERK2/1 activation. FGF2 did not trans-activate NOS3 promoters with deletions upstream of the consensus AP-1 site (TGAGTC A, -678 to -685). Trans-activation of wild-type NOS3 promoter by FGF2 was significantly inhibited when either the AP-1 or the cAMP-response element (CRE)-like sequence (TGCGTCA, -752 to -758) was mutated and was completely blocked when both were mutated. EMSA analyses showed that FGF2, but not VEGF, stimulated AP-1 and CRE DNA-protein complexes primarily composed of JunB and Fra1. Chromatin immunoprecipitation assays confirmed JunB/Fra1 binding to NOS3 promoter AP-1 and CRE elements in intact cells. FGF2, but not VEGF, stimulated JunB and Fra1 expressions; all preceded NOS3 up-regulation and were inhibited by PD98059. Down-regulation of JunB or Fra-1, but not c-Jun, blocked FGF2 stimulation of NOS3 expression and NO production. AP-1 inhibition suppressed FGF2 stimulation of NOS3 expression in human umbilical vein EC and uterine artery endothelial cells. Thus, FGF2 induction of NOS3 expression is mainly mediated by AP-1-dependent transcription involving JunB and Fra1 up-regulation via sustained ERK2/1 activation in endothelial cells.
Collapse
Affiliation(s)
- Eugenia Mata-Greenwood
- Department of Reproductive Medicine, University of California San Diego, La Jolla, California 92093, USA
| | | | | | | | | |
Collapse
|
9
|
Li CH, Cheng YW, Liao PL, Yang YT, Kang JJ. Chloramphenicol causes mitochondrial stress, decreases ATP biosynthesis, induces matrix metalloproteinase-13 expression, and solid-tumor cell invasion. Toxicol Sci 2010; 116:140-50. [PMID: 20338993 PMCID: PMC2886854 DOI: 10.1093/toxsci/kfq085] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Overuse and abuse of antibiotics can increase the risk of cancer. Chloramphenicol can inhibit both bacterial and mitochondrial protein synthesis, causing mitochondrial stress and decreased ATP biosynthesis. Chloramphenicol can accelerate cancer progression; however, the underlying mechanisms of chloramphenicol in carcinogenesis and cancer progression are still unclear. We found that chloramphenicol can induce matrix metalloproteinase (MMP)-13 expression and increase MMP-13 protein in conditioned medium, resulting in an increase in cancer cell invasion. Chloramphenicol also activated c-Jun N-terminal kinases (JNK) and phosphatidylinositol 3-kinase (PI-3K)/Akt signaling, leading to c-Jun protein phosphorylation. The activated c-Jun protein has been proven to activate binding to the MMP-13 promoter and also upregulate the amount of MMP-13. Both the SP 600125 (JNK inhibitor) and LY 294002 (PI-3K/Akt inhibitor) can inhibit chloramphenicol-induced c-Jun phosphorylation, MMP-13 expression, and cell invasion. Overexpression of the dominant-negative JNK and PI-3K p85 subunit also negate chloramphenicol-induced responses. Other antibiotics that cause mitochondrial stress and a decrease in ATP biosynthesis also induce MMP-13 expression. These findings suggest that chloramphenicol-induced PI-3K/Akt, JNK phosphorylation, and activator protein 1 activation might function as a novel mitochondrial stress signal that result in an increase of MMP-13 expression and MMP-13-associated cancer cell invasion. The findings of this study confirms that chloramphenicol, and other 70S ribosomal inhibitors, should be administered with caution, especially during cancer therapy.
Collapse
Affiliation(s)
- Ching-Hao Li
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | | | | | | | | |
Collapse
|
10
|
Wang X, Song Y, Jacobi JL, Tuan RS. Inhibition of histone deacetylases antagonized FGF2 and IL-1beta effects on MMP expression in human articular chondrocytes. Growth Factors 2009; 27:40-9. [PMID: 19107653 PMCID: PMC3612426 DOI: 10.1080/08977190802625179] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Fibroblast growth factor-2 (FGF2) and interleukin-1beta (IL-1beta) stimulate the expression of matrix metalloproteinases (MMPs) in articular chondrocytes, which may contribute to cartilage degradation and development of osteoarthritis. Histone deacetylases (HDACs) have recently been implicated in the regulation of MMP gene expression. To investigate the functional involvement of HDACs in the signaling pathway of FGF2 and IL-1beta, we examined the effects of HDAC inhibition on activities of FGF2 or IL-1beta on gene expression of MMP-1, MMP-3, MMP-13, a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS5), collagen type II, and aggrecan. Human articular chondrocyte cultures were treated with FGF2 or IL-1beta in the presence or absence of HDAC inhibitor (trichostatin A, TSA). Gene expression levels after treatments were assessed using quantitative real time PCR. Results showed that FGF2 and IL-1beta both increased MMP-1 and -13 expression, while IL-1beta also increased MMP-3 mRNA levels. These effects were attenuated in the presence of TSA in a dose dependent manner. In contrast to the effects on MMPs, FGF2 decreased mRNA levels of ADAMTS-5, which was not affected by HDAC inhibition. FGF2, IL-1beta, and TSA inhibited expression of aggrecan, while TSA also decreased mRNA levels of collagen type II. These findings showed that HDAC inhibition antagonized FGF2 and IL-1beta induced MMP expression. Combination of FGF2 and the HDAC inhibitor decreases both anabolic and catabolic genes, which may slow the cartilage turnover and be beneficial for maintaining cartilage integrity.
Collapse
Affiliation(s)
| | | | | | - Rocky S. Tuan
- Correspondence: Dr. Rocky S. Tuan, Cartilage Biology and Orthopaedics Branch, National Institute of Arthritis, and Musculoskeletal and Skin Diseases, NIH. Building 50, Room 1523, Bethesda, MD 20892-8022, Phone: 301-451-6854, Fax: 301-435-8017,
| |
Collapse
|
11
|
Blair HC, Zaidi M, Huang CLH, Sun L. The developmental basis of skeletal cell differentiation and the molecular basis of major skeletal defects. Biol Rev Camb Philos Soc 2008; 83:401-15. [PMID: 18710437 DOI: 10.1111/j.1469-185x.2008.00048.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vertebrate skeletal differentiation retains elements from simpler phyla, and reflects the differentiation of supporting tissues programmed by primary embryonic development. This developmental scheme is driven by homeotic genes expressed in sequence, with subdivision of skeletal primordia driven by a combination of seven transmembrane-pass receptors responding to Wnt-family signals, and by bone morphogenetic family signals that define borders of individual bones. In sea-dwelling vertebrates, an essentially complete form of the skeleton adapted by the land-living vertebrates develops in cartilage, based on type II collagen and hydrophilic proteoglycans. In bony fishes, this skeleton is mineralized to form a solid bony skeleton. In the land-living vertebrates, most of the skeleton is replaced by an advanced vascular mineralized skeleton based on type I collagen, which reduces skeletal mass while facilitating use of skeletal mineral for metabolic homeostasis. Regulation of the mammalian skeleton, in this context, reflects practical adaptations to the needs for life on land that are related to ancestral developmental signals. This regulation includes central nervous system regulation that integrates bone turnover with overall metabolism. Recent work on skeletal development, in addition, demonstrates molecular mechanisms that cause developmental bone diseases.
Collapse
Affiliation(s)
- Harry C Blair
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| | | | | | | |
Collapse
|
12
|
Ellman MB, An HS, Muddasani P, Im HJ. Biological impact of the fibroblast growth factor family on articular cartilage and intervertebral disc homeostasis. Gene 2008; 420:82-9. [PMID: 18565695 DOI: 10.1016/j.gene.2008.04.019] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2008] [Revised: 04/09/2008] [Accepted: 04/17/2008] [Indexed: 01/08/2023]
Abstract
Two members of the fibroblast growth factor (FGF) family, basic FGF (bFGF) and FGF-18, have been implicated in the regulation of articular and intervertebral disc (IVD) cartilage homeostasis. Studies on bFGF from a variety of species have yielded contradictory results with regards to its precise role in cartilage matrix synthesis and degradation. In contrast, FGF-18 is a well-known anabolic growth factor involved in chondrogenesis and articular cartilage repair. In this review, we examined the biological actions of bFGF and FGF-18 in articular and IVD cartilage, the specific cell surface receptors bound by each factor, and the unique signaling cascades and molecular pathways utilized to exert their biological effects. Evidence suggests that bFGF selectively activates FGF receptor 1 (FGFR1) to exert degradative effects in both human articular chondrocytes and IVD tissue via upregulation of matrix-degrading enzyme activity, inhibition of matrix production, and increased cell proliferation resulting in clustering of cells seen in arthritic states. FGF-18, on the other hand, most likely exerts anabolic effects in human articular chondrocytes by activating FGFR3, increasing matrix formation and cell differentiation while inhibiting cell proliferation, leading to dispersed cells surrounded by abundant matrix. The results from in vitro and in vivo studies suggest the potential usefulness of bFGF and FGFR1 antagonists, as well as FGF-18 and FGFR3 agonists, as potential therapies to prevent cartilage degeneration and/or promote cartilage regeneration and repair in the future.
Collapse
Affiliation(s)
- Michael B Ellman
- Department of Biochemistry, Rush University Medical Center, Chicago, IL 60612 USA
| | | | | | | |
Collapse
|
13
|
Behonick DJ, Xing Z, Lieu S, Buckley JM, Lotz JC, Marcucio RS, Werb Z, Miclau T, Colnot C. Role of matrix metalloproteinase 13 in both endochondral and intramembranous ossification during skeletal regeneration. PLoS One 2007; 2:e1150. [PMID: 17987127 PMCID: PMC2063465 DOI: 10.1371/journal.pone.0001150] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Accepted: 10/07/2007] [Indexed: 02/01/2023] Open
Abstract
Extracellular matrix (ECM) remodeling is important during bone development and repair. Because matrix metalloproteinase 13 (MMP13, collagenase-3) plays a role in long bone development, we have examined its role during adult skeletal repair. In this study we find that MMP13 is expressed by hypertrophic chondrocytes and osteoblasts in the fracture callus. We demonstrate that MMP13 is required for proper resorption of hypertrophic cartilage and for normal bone remodeling during non-stabilized fracture healing, which occurs via endochondral ossification. However, no difference in callus strength was detected in the absence of MMP13. Transplant of wild-type bone marrow, which reconstitutes cells only of the hematopoietic lineage, did not rescue the endochondral repair defect, indicating that impaired healing in Mmp13−/− mice is intrinsic to cartilage and bone. Mmp13−/− mice also exhibited altered bone remodeling during healing of stabilized fractures and cortical defects via intramembranous ossification. This indicates that the bone phenotype occurs independently from the cartilage phenotype. Taken together, our findings demonstrate that MMP13 is involved in normal remodeling of bone and cartilage during adult skeletal repair, and that MMP13 may act directly in the initial stages of ECM degradation in these tissues prior to invasion of blood vessels and osteoclasts.
Collapse
Affiliation(s)
- Danielle J. Behonick
- Department of Anatomy and Biomedical Sciences Graduate Program, University of California at San Francisco, San Francisco, California, United States of America
| | - Zhiqing Xing
- Cellular and Molecular Biology Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco General Hospital, San Francisco, California, United States of America
| | - Shirley Lieu
- Cellular and Molecular Biology Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco General Hospital, San Francisco, California, United States of America
| | - Jenni M. Buckley
- Orthopaedic Bioengineering Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco, California, United States of America
| | - Jeffrey C. Lotz
- Orthopaedic Bioengineering Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco, California, United States of America
| | - Ralph S. Marcucio
- Cellular and Molecular Biology Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco General Hospital, San Francisco, California, United States of America
| | - Zena Werb
- Department of Anatomy and Biomedical Sciences Graduate Program, University of California at San Francisco, San Francisco, California, United States of America
| | - Theodore Miclau
- Cellular and Molecular Biology Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco General Hospital, San Francisco, California, United States of America
| | - Céline Colnot
- Cellular and Molecular Biology Laboratory, Department of Orthopaedic Surgery, University of California at San Francisco, San Francisco General Hospital, San Francisco, California, United States of America
- * To whom correspondence should be addressed. E-mail:
| |
Collapse
|
14
|
Muddasani P, Norman JC, Ellman M, van Wijnen AJ, Im HJ. Basic fibroblast growth factor activates the MAPK and NFkappaB pathways that converge on Elk-1 to control production of matrix metalloproteinase-13 by human adult articular chondrocytes. J Biol Chem 2007; 282:31409-21. [PMID: 17724016 DOI: 10.1074/jbc.m706508200] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The pathology of joint destruction is associated with elevated production of basic fibroblast growth factor (bFGF) and matrix metalloproteinase-13 (MMP-13). In osteoarthritic joint disease, expression of bFGF and MMP-13 in chondrocytes and their release into the synovial fluid are significantly increased. We have previously found that the capacity for cartilage repair in human adult articular chondrocytes is severely compromised by minimal exposure to bFGF because bFGF reduces responsiveness to bone morphogenetic protein-7 and insulin-like growth factor-1 and induces MMP-13 through protein kinase Cdelta-dependent activation of multiple mitogen-activated protein kinase (MAPK) signaling pathways. Here we show using biochemical and molecular approaches that transcription factor Elk-1, a direct downstream target of MAPK, is a critical transcriptional activator of of MMP-13 by bFGF in human articular chondrocytes. We also provide evidence that Elk-1 is a direct target of NFkappaB and induces MMP-13 expression upon activation of the NFkappaB signaling pathway. Taken together, our results suggest that elevated expression of MMP-13 occurs through Elk-1 activation of both MAPK and NFkappaB signaling pathways, thus revealing a two-pronged biological mechanism by which bFGF controls the production of catabolic enzymes that are associated with excessive degradation of the cartilage matrix in degenerative joint diseases such as osteoarthritis.
Collapse
Affiliation(s)
- Prasuna Muddasani
- Department of Biochemistry, Rush University Medical Center, Chicago, Illinois 60612, USA
| | | | | | | | | |
Collapse
|
15
|
Selvamurugan N, Jefcoat SC, Kwok S, Kowalewski R, Tamasi JA, Partridge NC. Overexpression of Runx2 directed by the matrix metalloproteinase-13 promoter containing the AP-1 and Runx/RD/Cbfa sites alters bone remodeling in vivo. J Cell Biochem 2006; 99:545-57. [PMID: 16639721 DOI: 10.1002/jcb.20878] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The activator protein-1 (AP-1) and runt domain binding (Runx/RD/Cbfa) sites and their respective binding proteins, c-Fos/c-Jun and Runx2 (Cbfa1), regulate the rat matrix metalloproteinase-13 (MMP-13) promoter in both parathyroid hormone (PTH)-treated and differentiating osteoblastic cells in culture. To determine the importance of these regulatory sites in the expression of MMP-13 in vivo, transgenic mice containing either wild-type (-456 or -148) or AP-1 and Runx/RD/Cbfa sites mutated (-148A3R3) MMP-13 promoters fused with the E. coli lacZ reporter were generated. The wild-type transgenic lines expressed higher levels of bacterial beta-galactosidase in bone, teeth, and skin compared to the mutant and non-transgenic lines. Next, we investigated if overexpression of Runx2 directed by the MMP-13 promoter regulated expression of bone specific genes in vivo, and whether this causes morphological changes in these animals. Real time RT-PCR experiments identified increased mRNA expression of bone forming genes and decreased MMP-13 in the tibiae of transgenic mice (14 days and 6 weeks old). Histomorphometric analyses of the proximal tibiae showed increased bone mineralization surface, mineral apposition rate, and bone formation rate in the transgenic mice which appears to be due to decreased osteoclast number. Since MMP-13 is likely to play a role in recruiting osteoclasts to the bone surface, decreased expression of MMP-13 may cause reduced osteoclast-mediated bone resorption, resulting in greater bone formation in transgenic mice. In summary, we show here that the 148 bp upstream of the MMP-13 transcriptional start site is sufficient and necessary for gene expression in bone, teeth, and skin in vivo and the AP-1 and Runx/RD/Cbfa sites are likely to regulate this. Overexpression of Runx2 by these regulatory elements appears to alter the balance between the bone formation-bone resorption processes in vivo.
Collapse
Affiliation(s)
- Nagarajan Selvamurugan
- Department of Physiology and Biophysics, UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
| | | | | | | | | | | |
Collapse
|
16
|
Gallant-Behm CL, Olson ME, Hart DA. Cytokine and Growth Factor mRNA Expression Patterns Associated with the Hypercontracted, Hyperpigmented Healing Phenotype of Red Duroc Pigs: A Model of Abnormal Human Scar Development? J Cutan Med Surg 2006; 9:165-77. [PMID: 16502202 DOI: 10.1007/s10227-005-0105-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Skin wounds in red Duroc pigs heal with the formation of hypercontractile, hyperpigmented scars, similar in some respects to human hypertrophic scars. OBJECTIVE The goal of this study was to characterize the mRNA expression patterns for a subset of relevant cytokines, growth factors, receptors, and transcription factors involved in the red Duroc scarring phenotype. METHODS Full-thickness and deep dermal wounds were created on the backs of juvenile female red Duroc pigs. Samples were taken every two weeks postwounding and total RNA and DNA were extracted and quantified. RT-PCR was performed using porcine gene-specific primers for 15 relevant molecules. RESULTS The majority of molecules examined exhibited a biphasic pattern of expression, with peaks of expression at days 14 and 56 postinjury. CONCLUSIONS The molecular expression pattern observed correlates well with the gross healing phenotype and matrix molecule expression patterns previously reported in red Duroc pigs. These findings enhance our understanding of the processes associated with fibroproliferative scar-formation.
Collapse
Affiliation(s)
- Corrie L Gallant-Behm
- Department of Surgery, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | | |
Collapse
|
17
|
Varghese S, Rydziel S, Canalis E. Bone morphogenetic protein-2 suppresses collagenase-3 promoter activity in osteoblasts through a runt domain factor 2 binding site. J Cell Physiol 2005; 202:391-9. [PMID: 15389594 DOI: 10.1002/jcp.20130] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Transforming growth factor-beta (TGFbeta) superfamily of growth factors, which include bone morphogenetic proteins (BMPs), have multiple effects in osteoblasts. In this study, we examined the regulation of collagenase-3 promoter activity by BMP-2 in osteoblast-enriched (Ob) cells from fetal rat calvariae. BMP-2 suppressed the activity of a -2 kb collagenase-3 promoter/luciferase recombinant in a time- and dose-dependent manner. The BMP-2 effect on the collagenase-3 promoter was further tested in several collagenase-3 promoter deletion constructs and it was narrowed down to a -148 to -94 nucleotide segment of the promoter containing a runt domain factor 2 (Runx2) site at nucleotide -132 to -126. The effect of BMP-2 was obliterated in a collagenase-3 promoter/luciferase construct containing a mutated Runx2 (mRunx2) sequence indicating that the Runx2 site mediates the BMP-2 response. Electrophoretic mobility shift assays, using nuclear extracts from control and BMP-2-treated Ob cells, indicated that the Runx2 protein is a component of the specific DNA-protein complex formed on the Runx2 site and that the BMP-2 effect may be associated with minor protein modifications rather than major changes in the composition of specific proteins interacting with the Runx2 site. We confirmed that other members of the TGFbeta family can down-regulate the collagenase-3 promoter by showing that TGFbeta1 also suppresses the promoter activity in a time- and dose-dependent manner. In conclusion, this study demonstrates that BMP-2 and TGFbeta1 suppress collagenase-3 promoter activity in osteoblasts and establishes a link between BMP-2 action and collagenase-3 expression via Runx2, a major regulator of osteoblast formation and function.
Collapse
Affiliation(s)
- Samuel Varghese
- Department of Research, Saint Francis Hospital and Medical Center, Hartford, Connecticut 06105, USA.
| | | | | |
Collapse
|
18
|
Baroni T, Carinci P, Lilli C, Bellucci C, Aisa MC, Scapoli L, Volinia S, Carinci F, Pezzetti F, Calvitti M, Farina A, Conte C, Bodo M. P253R fibroblast growth factor receptor-2 mutation induces RUNX2 transcript variants and calvarial osteoblast differentiation. J Cell Physiol 2005; 202:524-35. [PMID: 15389579 DOI: 10.1002/jcp.20148] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Unregulated fibroblast growth factor 2 (FGF2) signaling caused by mutations in the fibroblast growth factor receptor (FGFR2) leads to human craniosynostosis such as the Apert syndrome. In an in vitro control model of calvarial osteoblasts from Apert patients carrying the FGFR2 P253R mutation, we studied the changes in cellular phenotype and evaluated the effects of FGF2. Compared with wild-type controls, osteocalcin mRNA was down-regulated in Apert osteoblasts, Runt-related transcription factor-2 (RUNX2) mRNA was differentially spliced, and FGF2 secretion was greater. Total protein synthesis, fibronectin and type I collagen secretion were up-regulated, while protease and glycosidase activities and matrix metalloproteinase-13 (MMP-13) transcription were decreased, suggesting an altered ECM turnover. Adding FGF2 increased protease and glycosidase activities and down-regulated fibronectin and type I collagen secretion in Apert osteoblasts. High affinity FGF2 receptors were up-regulated in Apert osteoblasts and analysis of signal transduction showed elevated levels of Grb2 tyrosine phosphorylation and the Grb2-p85 beta association, which FGF2 stimulation strongly reduced. All together these findings suggest increased constitutive receptor activity in Apert mutant osteoblasts and an autocrine loop involving the FGF2 pathway in modulation of Apert osteoblast behavior.
Collapse
Affiliation(s)
- Tiziano Baroni
- Institute of Histology and General Embryology, University of Perugia, Perugia, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Wang X, Manner PA, Horner A, Shum L, Tuan RS, Nuckolls GH. Regulation of MMP-13 expression by RUNX2 and FGF2 in osteoarthritic cartilage. Osteoarthritis Cartilage 2004; 12:963-73. [PMID: 15564063 DOI: 10.1016/j.joca.2004.08.008] [Citation(s) in RCA: 220] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2003] [Accepted: 08/18/2004] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To understand the molecular mechanisms that lead to increased MMP-13 expression and cartilage degeneration during the progression of osteoarthritis (OA), we have investigated the expression of the transcription factor RUNX2 in OA cartilage and the regulation of MMP-13 expression by RUNX2 and FGF2 in articular chondrocytes. DESIGN RUNX2 and MMP-13 expression in human OA and control cartilage was analyzed by immunohistochemistry. The effects of RUNX2 over-expression, with or without FGF2 treatment, on MMP-13 promoter activity and enzyme accumulation were measured in articular chondrocytes. Inhibitors of MEK/ERK were assayed for their ability to block FGF2 and RUNX2 up-regulation of the MMP-13 promoter. We analyzed RUNX2 phosphorylation in response to FGF2. RESULTS Fibrillated OA cartilage exhibited increased RUNX2 immunoreactivity when compared to control cartilage. RUNX2 co-localized with MMP-13 in clusters of chondrocytes in fibrillated OA cartilage. RUNX2 over-expression in cultured chondrocytes increased their responsiveness to FGF2 treatment, which led to increased MMP-13 expression. Inhibitors of MEK/ERK signaling blocked up-regulation of the MMP-13 promoter by RUNX2 and FGF2, and also blocked the activation of RUNX2 by FGF2. FGF2 treatment of articular chondrocytes increased RUNX2 phosphorylation approximately 2-fold. CONCLUSIONS Increased expression of RUNX2 in OA cartilage may contribute to increased expression of MMP-13. FGF2, which is present in OA synovial fluid, activated RUNX2 via the MEK/ERK pathway and increased MMP-13 expression. However, it is unlikely that RUNX2 is a substrate of ERK1/2. RUNX2 expression and activation may be a significant step in the progression of OA by promoting changes in gene expression and chondrocyte differentiation.
Collapse
Affiliation(s)
- Xibin Wang
- Cartilage Biology and Orthopaedics Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892-4872, USA
| | | | | | | | | | | |
Collapse
|
20
|
Naito J, Kaji H, Sowa H, Hendy GN, Sugimoto T, Chihara K. Menin suppresses osteoblast differentiation by antagonizing the AP-1 factor, JunD. J Biol Chem 2004; 280:4785-91. [PMID: 15563473 DOI: 10.1074/jbc.m408143200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mice null for menin, the product of the multiple endocrine neoplasia type 1 (MEN1) gene, exhibit cranial and facial hypoplasia suggesting a role for menin in bone formation. We have shown previously that menin is required for the commitment of multipotential mesenchymal stem cells into the osteoblast lineage in part by interacting with the bone morphogenetic protein (BMP)-2 signaling molecules Smad1/5, and the key osteoblast transcriptional regulator, Runx2 (Sowa H., Kaji, H., Hendy, G. N., Canaff, L., Komori, T., Sugimoto, T., and Chihara, K. (2004) J. Biol. Chem. 279, 40267-40275). However, menin inhibits the later differentiation of committed osteoblasts. The activator protein-1 (AP-1) transcription factor, JunD, is expressed in osteoblasts and has been shown to interact with menin in other cell types. Here, we examined the consequences of menin-JunD interaction on osteoblast differentiation in mouse osteoblastic MC3T3-E1 cells. JunD expression, assessed by immunoblot, gradually increased during osteoblast differentiation. Stable expression of JunD enhanced expression of the differentiation markers, Runx2, type 1 collagen (COL1), and osteocalcin (OCN) and alkaline phosphatase (ALP) activity and mineralization. Hence, JunD promotes osteoblast differentiation. In MC3T3-E1 cells in which menin expression was reduced by stable menin antisense DNA transfection, JunD levels were increased. When JunD and menin were co-transfected in MC3T3-E1 cells, they co-immunoprecipitated. JunD overexpression increased the transcriptional activity of an AP-1 luciferase reporter construct, and this activity was reduced by co-transfection of menin. Therefore, JunD and menin interact both physically and functionally in osteoblasts. Furthermore, menin overexpression inhibited the ALP activity induced by JunD. In conclusion, the data suggest that menin suppresses osteoblast maturation, in part, by inhibiting the differentiation actions of JunD.
Collapse
Affiliation(s)
- Junko Naito
- Division of Endocrinology/Metabolism, Neurology and Hematology/Oncology, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan
| | | | | | | | | | | |
Collapse
|
21
|
Chang W, Rewari A, Centrella M, McCarthy TL. Fos-related antigen 2 controls protein kinase A-induced CCAAT/enhancer-binding protein beta expression in osteoblasts. J Biol Chem 2004; 279:42438-44. [PMID: 15299028 DOI: 10.1074/jbc.m405549200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Transcription factor CCAAT/enhancer-binding protein beta (C/EBPbeta) plays an important role in hormone-dependent gene expression. In osteoblasts C/EBPbeta can increase insulin-like growth factor I (IGF-I) transcription following treatment with hormones that activate protein kinase A, but little is known as yet about the expression of C/EBPbeta itself in these cells. We initially showed that prostaglandin E2 (PGE2) rapidly enhances C/EBPbeta mRNA and protein expression, and in this study we identified a 3'-proximal region of the C/EBPbeta promoter containing a 541-bp upstream sequence that could account for this effect. PGE2-dependent activation of C/EBPbeta was blocked by expression of a mutated regulatory subunit of protein kinase A or by mutation of two previously identified cAMP-sensitive cis-acting regulatory elements within the promoter between bp -111 and -61. Nuclear protein binding to these elements was induced by PGE2, required new protein synthesis, and was sensitive to antibody to the transcription factor termed Fos-related antigen 2 (Fra-2). Fra-2 cDNA generated from rat osteoblasts by reverse transcriptase PCR was 95% homologous to human Fra-2, and PGE2 rapidly induced Fra-2 mRNA and protein expression. Consistent with these findings, over-expression of Fra-2 significantly increased C/EBPbeta promoter activity in PGE2-induced osteoblasts, whereas expression of Fra-2 lacking its activation domain had a dominant negative inhibitory effect. Together, these results reveal a significant, hormone-dependent role for Fra-2 in osteoblast function, both directly, through its ability to increase new C/EBPbeta gene expression, and indirectly, through downstream C/EBP sensitive genes.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Blotting, Western
- CCAAT-Enhancer-Binding Protein-beta/biosynthesis
- COS Cells
- Cell Line
- Cell Nucleus/metabolism
- Culture Media, Serum-Free
- Cyclic AMP/metabolism
- Cyclic AMP-Dependent Protein Kinases/metabolism
- DNA, Complementary/metabolism
- DNA-Binding Proteins/metabolism
- DNA-Binding Proteins/physiology
- Dose-Response Relationship, Drug
- Fos-Related Antigen-2
- Gene Expression Regulation
- Genes, Dominant
- Humans
- Insulin-Like Growth Factor I/metabolism
- Models, Biological
- Molecular Sequence Data
- Mutation
- Osteoblasts/metabolism
- Plasmids/metabolism
- Promoter Regions, Genetic
- Protein Binding
- Protein Structure, Tertiary
- RNA/chemistry
- RNA/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Homology, Amino Acid
- Transcription Factors/metabolism
- Transcription Factors/physiology
- Transfection
Collapse
Affiliation(s)
- Weizhong Chang
- Section of Plastic Surgery, Department of Surgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA
| | | | | | | |
Collapse
|
22
|
Selvamurugan N, Kwok S, Alliston T, Reiss M, Partridge NC. Transforming growth factor-beta 1 regulation of collagenase-3 expression in osteoblastic cells by cross-talk between the Smad and MAPK signaling pathways and their components, Smad2 and Runx2. J Biol Chem 2004; 279:19327-34. [PMID: 14982932 DOI: 10.1074/jbc.m314048200] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Transforming growth factor-beta (TGF-beta) plays a key role in osteoblast differentiation and bone development and remodeling. Collagenase-3 (matrix metalloproteinase-13) is expressed by osteoblasts and seems to be involved in osteoclastic bone resorption. Here, we show that TGF-beta 1 stimulates collagenase-3 expression in the rat osteoblastic cell line UMR 106-01 and requires de novo protein synthesis. Dominant-negative Smad2/3 constructs indicated that Smad signaling is essential for TGF-beta 1-stimulated collagenase-3 promoter activity. Inhibitors of the ERK1/2 and p38 MAPK pathways, but not the JNK pathway, reduced TGF-beta 1-stimulated collagenase-3 expression, indicating that the p38 MAPK and ERK1/2 pathways are also required for TGF-beta 1-stimulated collagenase-3 expression in UMR 106-01 cells. These inhibitors did not prevent nuclear localization of Smad proteins, but they inhibited Smad-mediated transcriptional activation. We have shown for the first time that Runx2 (a bone transcription factor and a potential substrate for the MAPK pathway) is phosphorylated in response to TGF-beta 1 treatment in osteoblastic cells. Cotransfection of Smad2 and Runx2 constructs had a cooperative effect on TGF-beta 1-stimulated collagenase-3 promoter activity in these cells. We further identified ligand-independent physical interaction between Smad2 and Runx2. Taken together, our results provide an important role for cross-talk between the Smad and MAPK pathways and their components in expression of collagenase-3 following TGF-beta 1 treatment in UMR 106-01 cells.
Collapse
Affiliation(s)
- Nagarajan Selvamurugan
- Department of Physiology and Biophysics, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
| | | | | | | | | |
Collapse
|
23
|
George M, Stein B, Müller O, Weis-Klemm M, Pap T, Parak WJ, Aicher WK. Metabolic activation stimulates acid secretion and expression of matrix degrading proteases in human osteoblasts. Ann Rheum Dis 2004; 63:67-70. [PMID: 14672894 PMCID: PMC1754733 DOI: 10.1136/ard.2002.005256] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Both cellular and matrix components of healthy bone are permanently renewed in a balanced homoeostasis. Osteoclastic bone resorption involves the expression of vacuolar-type ATPase proton pumps (vATPase) on the outer cell membrane and the secretion of matrix degrading proteases. Osteoblasts modulate the deposition of bone mineral components and secrete extracellular matrix proteins. OBJECTIVES To investigate the ability of osteoblasts and osteosarcoma to secrete acid and express matrix degrading proteases upon metabolic activation. To examine also the potential contribution of vATPases to proton secretion expressed on osteoblasts. METHODS Osteoblasts were isolated from trabecular bone and characterised by reverse transcriptase-polymerase chain reaction and immunohistochemistry. Proton secretion was analysed by a cytosensor microphysiometer. RESULTS Osteoblasts not only express matrix degrading proteases upon stimulation with tumour necrosis factor or with phorbol ester but they also secrete protons upon activation. Proton secretion by osteoblasts is associated partially with proton pump ATPases. CONCLUSION These data suggest that, in addition to monocyte derived osteoclasts, cytokine activated mesenchymal osteoblasts and osteosarcoma cells may contribute to the acidic milieu required for bone degradation.
Collapse
Affiliation(s)
- M George
- Institute for Applied Physics and Centre for Nanoscience, Ludwig-Maximilians, University Munich, Munich, Germany
| | | | | | | | | | | | | |
Collapse
|
24
|
Lewinson D, Rachmiel A, Rihani-Bisharat S, Kraiem Z, Schenzer P, Korem S, Rabinovich Y. Stimulation of Fos- and Jun-related genes during distraction osteogenesis. J Histochem Cytochem 2003; 51:1161-8. [PMID: 12923241 DOI: 10.1177/002215540305100906] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Bone cells respond to mechanical stimulation by gene expression. The molecular events involved in the translation of mechanical stimulation into cell proliferation and bone formation are not yet well understood. We looked for the expression of early-response genes of the AP-1 transcription factor complex in an in vivo bone regeneration system subjected to mechanical forces because these genes were found to be related to mechanotransduction and important for bone development. Sheep maxillary bone was distracted daily for 15 days. c-Jun and c-Fos were evaluated by Northern blotting analysis and immunohistochemistry in biopsy specimens removed at 8 and 15 days and were compared with post-osteotomy but not distracted repair tissue. Elevated levels of c-Jun and c-Fos mRNA were found after 8 days of distraction. Likewise, mesenchyme-like and fibroblast-like cells composing the 8-day distracted regeneration tissue showed increases in the intensity of immunostaining compared to cells in the corresponding non-distracted fracture repair tissue. After 15 days of distraction, when bone trabeculae start to form distally and proximally in the distracted regeneration tissue, mostly preosteoblasts and osteoblasts retained c-Fos and c-Jun immunoreactivity, similar to bone-associated cells in control non-distracted fracture repair tissue. We propose that the elevated expression of c-Jun and c-Fos is related to mechanical stimulation in this in vivo bone regeneration system.
Collapse
Affiliation(s)
- Dina Lewinson
- Department of Anatomy and Cell Biology, The Bruce Rappaport Faculty of Medicine, Technion, Israel.
| | | | | | | | | | | | | |
Collapse
|
25
|
Kim HJ, Lee MH, Park HS, Park MH, Lee SW, Kim SY, Choi JY, Shin HI, Kim HJ, Ryoo HM. Erk pathway and activator protein 1 play crucial roles in FGF2-stimulated premature cranial suture closure. Dev Dyn 2003; 227:335-46. [PMID: 12815619 DOI: 10.1002/dvdy.10319] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Cranial sutures are an important growth center of the cranial bones, and the suture space must be maintained to permit the cranial adjustments needed to accommodate brain growth. Craniosynostosis, characterized by premature suture closure, mainly results from mutations that generate constitutively active fibroblast growth factor (FGF) receptors. FGF signaling, thus, is responsible for the pathogenesis of craniosynostosis. Even though FGF activates many different signaling pathways, the one involved in premature suture closure has not been defined. We observed that placing FGF2-soaked bead on the osteogenic fronts of cultured mouse calvaria accelerates cranial suture closure and strongly induces the expression of osteopontin, an early marker of differentiated osteoblasts. FGF2 treatment also induced fos and jun mRNAs and later increased the nuclear levels of activator protein 1 (AP1). FGF2 stimulates the expression of osteopontin by inducing expression of AP1, which then binds to its response element in the osteopontin promoter. Blocking of the Erk pathway by PD98059 suppressed the AP1 and osteopontin expression stimulated by FGF2. Coincidently, blocking of the Erk pathway also significantly retarded FGF2-accelerated cranial suture closure. Thus, the Erk pathway mediates FGF/FGF receptor-stimulated cranial suture closure, probably by stimulating synthesis of AP1 that then stimulates the differentiation of osteoblasts.
Collapse
Affiliation(s)
- Hyun-Jung Kim
- Department of Biochemistry, School of Dentistry, Kyungpook National University, Daegu, Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Lafont J, Laurent M, Thibout H, Lallemand F, Le Bouc Y, Atfi A, Martinerie C. The expression of novH in adrenocortical cells is down-regulated by TGFbeta 1 through c-Jun in a Smad-independent manner. J Biol Chem 2002; 277:41220-9. [PMID: 12149257 DOI: 10.1074/jbc.m204405200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human NOV secreted glycoprotein (NOVH) is abundant in the fetal and adult adrenal cortex. The amount of NOVH increases in benign adrenocortical tumors and decreases in malignant adrenocortical tumors, suggesting that NOVH plays a role in tumorigenesis in the adrenal cortex. Transforming growth factor beta1 (TGFbeta1), fibroblast growth factor 2 (FGF2), and insulin growth factors (IGFs) play crucial roles in the physiology of the adrenal cortex. We investigated the effects of these factors on the expression of novH in the NCI H295R adrenocortical cell line. The amounts of NOVH protein and novH transcripts were down-regulated by TGFbeta1 and up-regulated by FGF2, whereas IGFs had no effect. Furthermore, the TGFbeta1-dependent inhibition of novH promoter activity was completely abrogated following site-directed mutation of two activating protein (AP-1) sequences (positions -473 and -447), whereas the stimulatory effect of FGF2 was not affected. Co-transfection with dominant negative forms of c-Jun and MEKK1 also abrogated novH-targeted regulation by TGFbeta1, whereas the overproduction of Smad proteins or dominant negative forms of Smad had no effect. Taken together, these results suggest that c-Jun and MEKK1 signaling but not Smad signaling are involved in the TGFbeta1-dependent decrease in NOVH in NCI H295R cells. In conclusion, our data provide evidence that novH is a new target of TGFbeta1; unlike other members of the CCN (cyr61, ctgf, nov) family, however, its expression is repressed rather than induced.
Collapse
Affiliation(s)
- Jérôme Lafont
- INSERM U515 and INSERM U482, Hôpital Saint-Antoine, 184 rue du Faubourg Saint-Antoine, 75571 Paris Cedex 12, France
| | | | | | | | | | | | | |
Collapse
|
27
|
Onodera S, Nishihira J, Iwabuchi K, Koyama Y, Yoshida K, Tanaka S, Minami A. Macrophage migration inhibitory factor up-regulates matrix metalloproteinase-9 and -13 in rat osteoblasts. Relevance to intracellular signaling pathways. J Biol Chem 2002; 277:7865-74. [PMID: 11751895 DOI: 10.1074/jbc.m106020200] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Neutral matrix metalloproteinases (MMPs) play an important role in bone matrix degradation accompanied by bone remodeling. We herein show for the first time that macrophage migration inhibitory factor (MIF) up-regulates MMP-13 (collagenase-3) mRNA of rat calvaria-derived osteoblasts. The mRNA up-regulation was seen at 3 h in response to MIF (10 microg/ml), reached the maximum level at 6-12 h, and returned to the basal level at 36 h. MMP-13 mRNA up-regulation was preceded by up-regulation of c-jun and c-fos mRNA. Tissue inhibitor of metalloproteinase (TIMP)-1 and MMP-9 (92-kDa type IV collagenase) were also up-regulated, but to a lesser extent. The MMP-13 mRNA up-regulation was significantly suppressed by genistein, herbimycin A and 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine. Similarly, a selective mitogen-activated protein kinase (MAPK) kinase (MEK)1/2 inhibitor (PD98059) and c-jun/activator protein (AP)-1 inhibitor (curcumin) suppressed MMP-13 mRNA up-regulation induced by MIF. The mRNA levels of c-jun and c-fos in response to MIF were also inhibited by PD98059. Consistent with these results, MIF stimulated phosphorylation of tyrosine, autophosphorylation of Src, activation of Ras, activation of extracellular signal-regulated kinases (ERK) 1/2, a MAPK, but not c-Jun N-terminal kinase or p38, and phosphorylation of c-Jun. Osteoblasts obtained from calvariae of newborn JunAA mice, defective in phosphorylation of c-Jun, or newborn c-Fos knockout (Fos -/- ) mice, showed much less induction of MMP-13 with the addition of MIF than osteoblasts obtained from wild-type or littermate control mice. Taken together, these results suggest that MIF increases the MMP-13 mRNA level of rat osteoblasts via the Src-related tyrosine kinase-, Ras-, ERK1/2-, and AP-1-dependent pathway.
Collapse
Affiliation(s)
- Shin Onodera
- Department of Orthopaedics, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | | | | | | | | | | | | |
Collapse
|
28
|
Eberhardt AW, Yeager-Jones A, Blair HC. Regional trabecular bone matrix degeneration and osteocyte death in femora of glucocorticoid- treated rabbits. Endocrinology 2001; 142:1333-40. [PMID: 11181552 DOI: 10.1210/endo.142.3.8048] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Glucocorticoids at pharmacological concentrations cause osteoporosis and aseptic necrosis, particularly in the proximal femur. Several mechanisms have been proposed, but the primary events are not clear. We studied changes in the bone structure and cellular activity in femora of glucocorticoid-treated rabbits before the occurrence of fracture or collapse. In rabbits treated 28 days with 4 micromol/kg.day of methylprednisolone acetate, changes in the cortical bone were minor. However, metabolic labeling showed that bone formation was virtually absent in the subarticular trabecular bone, and scanning electron microscopy showed resorption of 50-80% of the trabecular surface. Thus, reduction in bone synthesis and increased resorption were involved in bone loss. Vascular changes, which have been hypothesized to mediate glucocorticoid damage, were not seen, but histological changes suggested that trabecular bone was damaged. Matrix integrity was examined using laser scanning confocal microscopy to detect passive tetracycline adsorption. In treated animals, but not controls, tetracycline was adsorbed, in a novel lamellar pattern, in 50--200 microm regions extending deep into trabeculae. This showed that the matrix, which is normally impervious, was exposed at these sites. TUNEL assays showed that matrix damage correlated with cell death in the subarticular trabecular bone of treated animals. The pattern of cell death involving cohorts of osteoblasts and osteocytes comprised up to half of the bone volume in affected regions and is consistent with an apoptotic mechanism. Small numbers of TUNEL-labeled osteoblasts, but no osteocytes, were detected in control bone. We conclude that exposure of bone matrix permeability and that regional cell death consistent with apoptosis is an early event in glucocorticoid-induced bone damage.
Collapse
Affiliation(s)
- A W Eberhardt
- Department Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | | | | |
Collapse
|