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Mazzoni A, Maravić T, Tezvergil-Mutluay A, Tjäderhane L, Scaffa PMC, Seseogullari-Dirihan R, Bavelloni A, Gobbi P, Pashley DH, Tay FR, Breschi L. Biochemical and immunohistochemical identification of MMP-7 in human dentin. J Dent 2018; 79:90-95. [PMID: 30367893 DOI: 10.1016/j.jdent.2018.10.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 09/23/2018] [Accepted: 10/22/2018] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVES Matrix metalloproteinases (MMPs) are dentinal endogenous enzymes claimed to have a vital role in dentin organic matrix breakdown. The aim of the study was to investigate presence, localization and distribution of MMP-7 in sound human dentin. METHODS Dentin was powdered, demineralized and dissolved in isoelectric focusing buffer. Resolved proteins were transferred to nitrocellulose membranes for western blotting (WB) analyses. For the zymographic analysis, aliquots of dentin protein were electrophoresed in 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis containing fluorescently labeled gelatin. Further, the concentrations of dentinal MMPs were measured using Fluorescent Microsphere Immunoassay with a human MMP-MAP multiplex kit. Pre- and post-embedding immunolabeling technique was used to investigate the localization and distribution of MMP-7 in dentin. Dentin was cryo-fractured, the fragments partially decalcified and labeled with a primary monoclonal anti-MMP-7 and a secondary antibody conjugated with gold nanoparticles. MMP-7 labelings were identified in the demineralized dentin matrix as highly electron-dense dispersed gold particles. RESULTS WB and zymographic analysis of extracted dentin proteins showed presence of MMP-7 (∼20-28 KDa). Further, MMP-7 was found in the supernatants of the incubated dentin beams using Fluorescent Microsphere Immunoassay. FEI-SEM and TEM analyses established MMP-7 as an intrinsic constituent of the human dentin organic matrix. CONCLUSION This study demonstrated that MMP-7 is an endogenous component of the human dentin fibrillar network. CLINICAL SIGNIFICANCE It is pivotal to understand the underlying processes behind dentin matrix remodeling and degradation in order to develop the most optimal clinical protocols and ensure the longevity of dental restorations.
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Affiliation(s)
- Annalisa Mazzoni
- Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna-Alma Mater Studiorum, Via San Vitale 59, Bologna, Italy.
| | - Tatjana Maravić
- Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna-Alma Mater Studiorum, Via San Vitale 59, Bologna, Italy.
| | - Arzu Tezvergil-Mutluay
- Department of Restorative Dentistry and Cariology, Adhesive Dentistry Research Group Institute of Dentistry, University of Turku, FI-20014 Turun Yliopisto, Turku Finland; Turku University Hospital, Kiinamyllynkatu 4-8 Turku, Finland.
| | - Leo Tjäderhane
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki University Hospital, Mannerheimintie 172, 00014 Helsinki, Finland; Research Unit of Oral Health Sciences, Medical Research Center Oulu (MRC Oulu), Oulu University Hospital and University of Oulu, Pentti Kaiteran katu 1, Linnanmaa, Oulu, Finland.
| | | | - Roda Seseogullari-Dirihan
- Department of Restorative Dentistry and Cariology, Adhesive Dentistry Research Group Institute of Dentistry, University of Turku, FI-20014 Turun Yliopisto, Turku Finland; Turku University Hospital, Kiinamyllynkatu 4-8 Turku, Finland.
| | - Alberto Bavelloni
- Laboratory of Musculoskeletal Cell Biology, Rizzoli Orthopedic Institute, Via di Barbiano, 1/10, 40136 Bologna, Italy.
| | - Pietro Gobbi
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, Via Aurelio Saffi 2, Urbino, Italy.
| | - David H Pashley
- The Dental College of Georgia, Augusta University, 1430 John Wesley Gilbert Drive, Augusta, Georgia, USA.
| | - Franklin R Tay
- The Dental College of Georgia, Augusta University, 1430 John Wesley Gilbert Drive, Augusta, Georgia, USA.
| | - Lorenzo Breschi
- Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna-Alma Mater Studiorum, Via San Vitale 59, Bologna, Italy.
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Stape THS, Tjäderhane L, Tezvergil-Mutluay A, Da Silva WG, Dos Santos Silva AR, da Silva WJ, Marques MR. In situ analysis of gelatinolytic activity in human dentin. Acta Histochem 2018; 120:136-141. [PMID: 29373132 DOI: 10.1016/j.acthis.2017.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/27/2017] [Accepted: 12/29/2017] [Indexed: 11/29/2022]
Abstract
Matrix metalloproteinases (MMPs) such as gelatinases are differentially expressed in human tissues. These enzymes cleave specific substrates involved in cell signaling, tissue development and remodeling and tissue breakdown. Recent evidences show that gelatinases are crucial for normal dentin development and their activity is maintained throughout the entire tooth function in the oral cavity. Due to the lack of information about the exact location and activity of gelatinases in mature human dentin, the present study was designed to examine gelatinolytic levels in sound dentin. In situ zymography using confocal microscopy was performed on both mineralized and demineralized dentin samples. Sites presenting gelatinase activity were identified throughout the entire biological tissue pursuing different gelatinolytic levels for distinct areas: predentin and dentinal tubule regions presented higher gelatinolytic activity compared to intertubular dentin. Dentin regions with higher gelatinolytic activity immunohistochemically were partially correlated with MMP-2 expression. The maintenance of gelatinolytic activity in mature dentin may have biological implications related to biomineralization of predentin and tubular/peritubular dentinal regions, as well as regulation of defensive mechanisms of the dentin-pulp complex.
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Affiliation(s)
- Thiago Henrique Scarabello Stape
- Adhesive Dentistry Research Group, Institute of Dentistry, University of Turku, Turku, Finland; Department of Restorative Dentistry and Cariology, University of Turku, Turku, Finland
| | - Leo Tjäderhane
- Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland and Helsinki University Hospital, Helsinki, Finland; Research Unit of Oral Health Sciences, and Medical Research Center Oulu (MRC Oulu), Oulu University Hospital and University of Oulu, Oulu, Finland
| | - Arzu Tezvergil-Mutluay
- Adhesive Dentistry Research Group, Institute of Dentistry, University of Turku, Turku, Finland; Department of Restorative Dentistry and Cariology, University of Turku, Turku, Finland
| | - Wagner Gomes Da Silva
- Department of Oral Diagnosis, Semiology Area, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Alan Roger Dos Santos Silva
- Department of Oral Diagnosis, Semiology Area, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Wander José da Silva
- Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil
| | - Marcelo Rocha Marques
- Department of Morphology Division of Histology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil.
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Schure R, Costa KD, Rezaei R, Lee W, Laschinger C, Tenenbaum HC, McCulloch CA. Impact of matrix metalloproteinases on inhibition of mineralization by fetuin. J Periodontal Res 2012; 48:357-66. [DOI: 10.1111/jre.12015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2012] [Indexed: 12/17/2022]
Affiliation(s)
- R. Schure
- Discipline of Periodontology; Faculty of Dentistry; University of Toronto; Toronto ON Canada
| | - K. D. Costa
- Matrix Dynamics Group; University of Toronto; Toronto ON Canada
| | - R. Rezaei
- Discipline of Periodontology; Faculty of Dentistry; University of Toronto; Toronto ON Canada
| | - W. Lee
- Matrix Dynamics Group; University of Toronto; Toronto ON Canada
| | - C. Laschinger
- Matrix Dynamics Group; University of Toronto; Toronto ON Canada
| | - H. C. Tenenbaum
- Discipline of Periodontology; Faculty of Dentistry; University of Toronto; Toronto ON Canada
| | - C. A. McCulloch
- Matrix Dynamics Group; University of Toronto; Toronto ON Canada
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Mazzoni A, Breschi L, Carrilho M, Nascimento FD, Orsini G, Ruggeri A, Gobbi P, Manzoli L, Tay FR, Pashley DH, Tjäderhane L. A review of the nature, role, and function of dentin non-collagenous proteins. Part II: enzymes, serum proteins, and growth factors. ACTA ACUST UNITED AC 2012. [DOI: 10.1111/j.1601-1546.2012.00268.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Wathes DC, Cheng Z, Fenwick MA, Fitzpatrick R, Patton J. Influence of energy balance on the somatotrophic axis and matrix metalloproteinase expression in the endometrium of the postpartum dairy cow. Reproduction 2011; 141:269-81. [PMID: 21123519 PMCID: PMC3021913 DOI: 10.1530/rep-10-0177] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2010] [Revised: 11/01/2010] [Accepted: 11/26/2010] [Indexed: 12/26/2022]
Abstract
Postpartum dairy cows enter a period of negative energy balance (NEB) associated with low circulating IGF1, during which the uterus must undergo extensive repair following calving. This study investigated the effects of NEB on expression of IGF family members and related genes in the involuting uterus. Cows were allocated to two treatments using differential feeding and milking regimes to produce mild NEB or severe NEB (SNEB). Uterine endometrial samples collected 2 weeks post partum were analysed by quantitative PCR. The expression of IGF-binding protein 4 (IGFBP4) mRNA increased in the endometrium of SNEB cows, with trends towards increased IGFBP1 and reduced IGFBP6 expression. There were no significant differences between treatments in mRNA expression of IGF1, IGF2 or of any hormone receptor studied, but significant correlations across all cows in the expression levels of groups of receptors suggested common regulatory mechanisms: type 1 IGF receptor (IGF1R), IGF2R and insulin receptor (INSR); GHR with ESR1; and ESR2 with NR3C1. The expression of IGF1R and INSR also positively correlated with the circulating urea concentration. Matrix metalloproteinases (MMPs) are important in tissue remodelling and can affect IGF signalling via interaction with IGFBPs. The expression levels of MMP1, MMP3, MMP9 and MMP13 mRNAs all showed major upregulation in the endometrium of cows in SNEB and all except MMP9 were highly correlated with expression of IGFBP4. Alpha(2)-HS-glycoprotein (AHSG) and PDK4, two genes implicated in insulin resistance, were also highly expressed in SNEB. These results suggest that cows in SNEB experience alterations to the IGF and insulin signalling pathways in the postpartum endometrium. This may affect the rate of tissue repair with a possible negative impact on subsequent fertility.
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Affiliation(s)
- D Claire Wathes
- Reproduction Group, Department of Veterinary Basic Sciences, Royal Veterinary College, London, UK.
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Abstract
Cystatins, the classical inhibitors of C1 cysteine proteinases, have been extensively studied and reviewed in the literature. Over the last 20 years, however, proteins containing cystatin domains but lacking protease inhibitory activities have been identified, and most likely more will be described in the near future. These proteins together with family 1, 2, and 3 cystatins constitute the cystatin superfamily. Mounting evidence points to the new roles that some members of the superfamily have acquired over the course of their evolution. This review is focused on the roles of cystatins in: 1) tumorigenesis, 2) stabilization of matrix metalloproteinases, 3) glomerular filtration rate, 4) immunomodulation, and 5) neurodegenerative diseases. It is the goal of this review to get as many investigators as possible to take a second look at the cystatin superfamily regarding their potential involvement in serious human ailments.
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Affiliation(s)
- Josiah Ochieng
- Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN 37208, USA.
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La Belle JT, Gerlach JQ, Svarovsky S, Joshi L. Label-Free Impedimetric Detection of Glycan−Lectin Interactions. Anal Chem 2007; 79:6959-64. [PMID: 17658764 DOI: 10.1021/ac070651e] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A compact biosensor for a label-free, rapid (<80 s) detection of glycan-lectin interactions using ac impedance measurements was developed for the first time. A galactose-binding peanut agglutinin (PNA) and sialic acid-binding Sambucus nigra agglutinin (SNA) were covalently surface-immobilized on the layered Cu/Ni/Au printed circuit board (PCB) electrodes. Samples of artificial and natural glycoconjugates consisting of (1) gold glyconanoparticles encapsulated with approximately 90-100 copies of TF-antigen disaccharide Galalpha1-3GalNAc (TF-AuNP), (2) asialofetuin (ASF) containing both LacNAc (Galbeta1-4GlcNAc) and TF-antigen, and (3) fetuin (FET), the sialylated glycoform of ASF. The samples were run separately on PNA- and SNA-immobilized PCB electrodes. Our results indicate that TF-AuNP could be rapidly and reliably detected up to 1 pg/mL (13 fM) concentration on PNA electrode but, as expected, yielded no response on the SNA electrode. ASF and FET glycocoproteins were unambiguously detectable up to 10 pg/mL (150 fM) on PNA and SNA electrodes, respectively. Moreover, the technique allowed us to observe glyco-microheterogeneity of FET as well as establish the presence of two isoforms of SNA lectin, SNA-I and SNA-II, in one of the vendor's formulations. Further elaboration of the described technology into novel electrochemically driven lectin arrays may find applications in diagnosis of cancer and other diseases with multiple glycobiomarkers or as a rapid low-cost bioanalytical tool for glycoproteome analyses.
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Affiliation(s)
- Jeffrey T La Belle
- Center for Bioelectronics and Biosensors, The Biodesign Institute, Arizona State University, 1001 South McAllister Avenue, Tempe, Arizona 82287-6001, USA
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Kübler D, Gosenca D, Wind M, Heid H, Friedberg I, Jahnen-Dechent W, Lehmann WD. Proteolytic processing by matrix metalloproteinases and phosphorylation by protein kinase CK2 of fetuin-A, the major globulin of fetal calf serum. Biochimie 2007; 89:410-8. [PMID: 17110014 DOI: 10.1016/j.biochi.2006.10.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Accepted: 10/13/2006] [Indexed: 11/27/2022]
Abstract
Bovine fetuin-A is a member of a glycoprotein family with a wide spectrum of functions. Until now the bovine protein has been thought to be a single-chain protein. Recently we have shown that native bovine plasma fetuin-A partially exists as a disulfide-bridged two-chain protein with a heavy N-terminal and a lighter C-terminal chain similar to the structure of human fetuin-A homologue (alpha2HS glycoprotein), and also is partially phosphorylated at residues Ser120, Ser302, Ser305 and Ser306 (Wind et al., Anal. Biochem. 317 (2003) 26-33). Both fetuin-A modifications, the phosphorylation at the four sites as well as the proteolysis which causes longer or shorter light chains (termed lc-1 and lc-2, respectively), are probably brought about by targeted enzymatic activities which still need to be defined. In this study we show that authentic bovine fetuin-A disulfide-bridged two-chain forms, which include the original C-terminus, were liberated from the single-chain precursor by metalloproteinases MMP-3 (stromelysin-1) and MMP-7 (matrilysin), but not by elastase, cathepsin E and cathepsin G. Peptide sequencing suggested cleavage sites chiefly at the Pro277-Ser278 or Arg294-His295 peptide bonds. Fetuin-A radioactive phosphorylation in vitro by protein kinase CK2 caused (32)P incorporation into the fetuin-A light chain lc-1 but not lc-2 or the fetuin-A heavy chain, as revealed by MMP assisted proteolysis. Analysis by nanoESI-MS pinpointed phosphorylation at the native phospho-residues Ser302, Ser305 and Ser306 by increased relative abundance following in vitro phosphorylation. Moreover, CK2 phosphorylation of synthetic C-terminal fetuin-A peptides, used as effective controls to the native protein, strongly implies that CK2 is involved in the in vivo phosphorylation of fetuin-A. The phosphorylation of N-terminally truncated peptide homologs seemed highly dependent on the sequence context N-terminal of the phosphorylation sites, thus providing a likely explanation for the non-phosphorylation of the light chain lc-2 in native fetuin-A.
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Affiliation(s)
- Dieter Kübler
- Mechanisms of Biomolecular Interactions (A060), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
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Vonlaufen N, Naguleswaran A, Gianinazzi C, Hemphill A. Characterization of the fetuin-binding fraction of Neospora caninum tachyzoites and its potential involvement in host-parasite interactions. Parasitology 2007; 134:805-17. [PMID: 17291396 DOI: 10.1017/s0031182006002186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Terminal sialic acid residues on surface-associated glycoconjugates mediate host cell interactions of many pathogens. Addition of sialic acid-rich fetuin enhanced, and the presence of the sialidiase inhibitor 2-deoxy-2,3-dehydro-N-acetylneuraminic acid reduced, the physical interaction of Neospora caninum tachyzoites and bradyzoites with Vero cell monolayers. Thus, Neospora extracts were subjected to fetuin-agarose affinity chromatography in order to isolate components potentially interacting with sialic acid residues. SDS-PAGE and silver staining of the fetuin binding fraction revealed the presence of a single protein band of approximately 65 kDa, subsequently named NcFBP (Neospora caninum fetuin-binding protein), which was localized at the apical tip of the tachyzoites and was continuously released into the surrounding medium in a temperature-independent manner. NcFBP readily interacted with Vero cells and bound to chondroitin sulfate A and C, and anti-NcFBP antibodies interfered in tachyzoite adhesion to host cell monolayers. In additon, analysis of the fetuin binding fraction by gelatin substrate zymography was performed, and demonstrated the presence of two bands of 96 and 140 kDa exhibiting metalloprotease-activity. The metalloprotease activity readily degraded glycosylated proteins such as fetuin and bovine immunoglobulin G heavy chain, whereas non-glycosylated proteins such as bovine serum albumin and immunoglobulin G light chain were not affected. These findings suggest that the fetuin-binding fraction of Neospora caninum tachyzoites contains components that could be potentially involved in host-parasite interactions.
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Affiliation(s)
- N Vonlaufen
- Institute of Parasitology, Vetsuisse Faculty, University of Berne, Länggass-Strasse 122, CH-3012 Berne, Switzerland
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Ray S, Lukyanov P, Ochieng J. Members of the cystatin superfamily interact with MMP-9 and protect it from autolytic degradation without affecting its gelatinolytic activities. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2003; 1652:91-102. [PMID: 14644044 DOI: 10.1016/j.bbapap.2003.08.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Matrix metalloproteinases (MMPs), like other proteinases, can undergo autolytic degradation once activated in vivo. Whereas the activities of these enzymes are tightly regulated by tissue inhibitors of matrix metalloproteinases (TIMPs), it is not clear mechanistically how these enzymes are protected from autolysis in their active state. We previously reported that MMPs particularly MMP-9 and MMP-2 interact with the serum glycoprotein fetuin-A [Arch. Biochem. Biophys. (1995) 322, 250], a member of the cystatin superfamily. In the present analyses, we demonstrate that this interaction protects MMP-9 from autolytic degradation without interfering with its enzymatic activity, allowing it to efficiently digest gelatin. Our data demonstrate that MMP-9 binds to members of the cystatin family with K(diss) ranging from 25 to 58 nM for fetuin-A and 1.5-1.9 microM for cystatin C. The ability of fetuin-A to protect MMP-9 from autolysis requires a molar ratio of at least 8:1 (fetuin-A/MMP-9). More interestingly, our data show that the other members of the cystatin also have the ability to protect MMP-9 from autolysis, provided they are in molar excess relative to MMP-9. Taken together, our data suggest that cystatins, particularly fetuin-A, in any cellular compartment including the circulatory system, efficiently protect MMP-9 and possibly other MMPs from autolysis. This mechanism ensures the digestion of the preferred substrate for MMP-9 without sacrificing the enzyme in the process.
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Affiliation(s)
- Sanhita Ray
- Department of Biochemistry, Meharry Medical College, 1005 Dr. D.B. Todd Jr. Blvd., Nashville, TN 37208, USA
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Tajirian T, Dennis JW, Swallow CJ. Regulation of human monocyte proMMP-9 production by fetuin, an endogenous TGF-beta antagonist. J Cell Physiol 2000; 185:174-83. [PMID: 11025439 DOI: 10.1002/1097-4652(200011)185:2<174::aid-jcp2>3.0.co;2-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Members of the matrix metalloproteinase family of enzymes degrade specific components of the extracellular matrix. MMP-9 is a type IV/V collagenase necessary for normal osteogenesis and is increased in inflammatory and neoplastic conditions. In such destructive diseases as emphysema and arthritis, and in epithelial cancers, MMP-9 is produced by cells of the monocyte lineage. Fetuin, a prominent serum glycoprotein, binds to and inactivates TGF-beta family members and through this mechanism regulates osteogenesis (Binkert et al., 1999, J Biol Chem 274:28514-28520.). We studied the effects of TGF-beta1 and fetuin on proMMP-9 release by the human monocyte line THP-1. Exogenous TGF-beta1 stimulated proMMP-9 release by THP-1 cells, with half-maximal stimulation at approximately 0.01 ng/ml TGF-beta1. Human fetuin (0.5-2 microM) partially inhibited this stimulation. Human fetuin alone stimulated THP-1 monocyte proMMP-9 release, with half maximal stimulation at approximately 0.25 microM fetuin. Neutralizing antibody specific for TGF-beta1 also stimulated proMMP-9 release, suggesting that endogenously-derived TGF-beta1 has an inhibitory effect. In freshly isolated human peripheral blood monocytes, fetuin stimulated proMMP-9 release with a dose-response curve similar to that observed in THP-1 cells. Human fetuin also activated proMMP-9 present in THP-1 conditioned medium. Taken together, these data suggest that under physiological conditions, fetuin facilitates matrix degradation by monocyte-derived MMP-9, both by opposing the autocrine inhibitory effect of endogenous TGF-beta1 on proMMP-9 release, and by activating proMMP-9 in the pericellular milieu. Conversely, fetuin may limit the stimulation of monocyte proMMP-9 release by high levels of exogenous TGF-beta1. Such modulation could prove important under pathological conditions where TGF-beta1 derived from paracrine sources is abundant, such as in epithelial malignancies.
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Affiliation(s)
- T Tajirian
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, Canada
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