Biosynthesis of tissue inhibitor of metalloproteinases by human fibroblasts in culture. Stimulation by 12-O-tetradecanoylphorbol 13-acetate and interleukin 1 in parallel with collagenase

Identification of a Novel Activated NK-Associated Gene Score Associated with Diagnosis and Biological Therapy Response in Ulcerative Colitis

INTRODUCTION

Natural killer (NK) cells are associated with the pathogenesis of ulcerative colitis (UC); however, their precise contributions remain unclear. The present study aimed to investigate the diagnostic value of the activated NK-associated gene (ANAG) score in UC and evaluate its predictive value in response to biological therapy.

METHODS

Bulk RNA-seq and scRNA-seq datasets were obtained from the Gene Expression Omnibus (GEO) and Single Cell Portal (SCP) databases. In the bulk RNA-seq, differentially expressed genes (DEGs) were screened by the "Batch correction" and "Robust rank aggregation" (RRA) methods. The immune infiltration landscape was estimated using single-sample gene set enrichment analysis (ssGSEA) and CIBERSORT. DEGs that correlated with activated NK cells were identified as activated NK-associated genes (ANAGs). Protein-protein interaction (PPI) analysis and least absolute shrinkage and selection operator (LASSO) regression were used to screen key ANAGs and establish an ANAG score. The expression levels of the four key ANAGs were validated in human samples by real-time quantitative polymerase chain reaction (RT-qPCR) and immunofluorescence. The potential therapeutic drugs for UC were identified using the DSigDB database. Through scRNA-seq data analysis, the cell scores based on the ANAGs were calculated by "AddModuleScore" and "AUCell."

RESULTS

Immune infiltration analysis revealed a higher abundance of activated NK cells in noninflamed UC tissues (ssGSEA, p < 0.001; CIBERSORT, p < 0.01). Fifty-four DEGs correlated with activated NK cells were identified as ANAGs. The ANAG score was established using four key ANAGs (SELP, TIMP1, MMP7, and ABCG2). The ANAG scores were significantly higher in inflamed tissues (p < 0.001) and in biological therapy nonresponders (NR) tissues before treatment (golimumab, p < 0.05; ustekinumab, p < 0.001). The ANAG score demonstrated an excellent diagnostic value (AUC = 0.979). Patients with higher ANAG scores before treatment were more likely to experience a lack of response to golimumab or ustekinumab (golimumab, p < 0.05; ustekinumab, p < 0.001).

CONCLUSION

This study established a novel ANAG score with the ability to precisely diagnose UC and distinguish the efficacy of biological treatment.

In vitro effect of triamcinolone and platelet-rich plasma on cytokine levels of elbow lateral epicondylitis-derived cells

Background

The pathogenesis and treatment of lateral elbow epicondylitis (LEE) are still controversial. The purpose of the current study was to evaluate the production of inflammatory cytokines by LEE-derived cells and to compare the anti-inflammatory effect of triamcinolone acetonide with platelet-rich plasma (PRP) on cytokines production in primary culture of these cells.

Methods

Third passage cells from primary cultures of LEE were assessed for the production of the cytokines IL-1β, IL-6, IL-8, IL-10 and TNF-α by immune-enzymatic assay (ELISA), after the treatment with 1, 10 and 100 μM triamcinolone compared to no treated controls at the time points 6, 12, 18, 24, 48, 72 and 96 h, and to PRP at 48, 72 and 96 h.

Results

The cytokines IL-6 and IL-8 were produced in high concentrations by LEE cells. One, 10 and 100 μM triamcinolone induced significant decrease in the production of IL-6 and IL-8 at 48, 72 and 96 h, adding the time point 12 h for IL-8. Compared to controls, PRP caused a significant increase in the production of IL-6 and IL-8 and there was a significant increase in IL-10 production with the use of 100 μM triamcinolone at 48 h. The production of IL1-β and TNF-α was very low and did not change when the cultures were treated with triamcinolone or PRP.

Conclusion

LEE-derived cells produce IL-6 and IL-8, confirming the inflammatory nature of this condition. While triamcinolone inhibited the production of IL-6 and IL-8 by LEE cells, PRP induced an increase in these cytokines compared with controls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-02990-0.

Vitamin D Inhibits Expression and Activity of Matrix Metalloproteinase in Human Lung Fibroblasts (HFL-1) Cells

BACKGROUND

Low levels of serum vitamin D is associated with several lung diseases. The production and activation of matrix metalloproteinases (MMPs) may play an important role in the pathogenesis of emphysema. The aim of the current study therefore is to investigate if vitamin D modulates the expression and activation of MMP-2 and MMP-9 in human lung fibroblasts (HFL-1) cells.

METHODS

HFL-1 cells were cast into three-dimensional collagen gels and stimulated with or without interleukin-1β (IL-1β) in the presence or absence of 100 nM 25-hydroxyvitamin D (25(OH)D) or 1,25-dihydroxyvitamin D (1,25(OH)2D) for 48 hours. Trypsin was then added into the culture medium in order to activate MMPs. To investigate the activity of MMP-2 and MMP-9, gelatin zymography was performed. The expression of the tissue inhibitor of metalloproteinase (TIMP-1, TIMP-2) was measured by enzyme-linked immunosorbent assay. Expression of MMP-9 mRNA and TIMP-1, TIMP-2 mRNA was quantified by real time reverse transcription polymerase chain reaction.

RESULTS

IL-1β significantly stimulated MMP-9 production and mRNA expression. Trypsin converted latent MMP-2 and MMP-9 into their active forms of MMP-2 (66 kDa) and MMP-9 (82 kDa) within 24 hours. This conversion was significantly inhibited by 25(OH)D (100 nM) and 1,25(OH)2D (100 nM). The expression of MMP-9 mRNA was also significantly inhibited by 25(OH)D and 1,25(OH)2D.

CONCLUSION

Vitamin D, 25(OH)D, and 1,25(OH)2D play a role in regulating human lung fibroblast functions in wound repair and tissue remodeling through not only inhibiting IL-1β stimulated MMP-9 production and conversion to its active form but also inhibiting IL-1β inhibition on TIMP-1 and TIMP-2 production.

Abundance of calpain and aggrecan-cleavage products of calpain in degenerated human intervertebral discs

OBJECTIVE

To assess the expression of calpains and calpain-induced aggrecan fragmentation in early and advanced stages of degeneration of human intervertebral discs (IVDs).

DESIGN

Disc tissue samples of 55 patients (mean age, 51.2 ± 22.3 years) who underwent intervertebral fusion were divided into groups with early and advanced degeneration based on the Thompson magnetic resonance imaging (MRI) scale. In advanced degeneration group, five patients (mean age, 35.5 ± 11.4 years) of lumbar disc herniation (LDH) were included. Protein levels of m- and μ-calpains and their inhibitor calpastatin were assayed, and immunohistochemical techniques were used to localize and quantify the production of the enzymes. To investigate calpain activity, we assayed purified aggrecan fragmentation in disc tissue by Western blotting and immunohistochemistry with VPGVA antibody, which recognizes the m-calpain generated neo-epitope GVA.

RESULTS

Discs at early stages of degeneration expressed low levels of m- and μ-calpains and calpastatin, and few cells expressed degenerative enzymes. At more advanced stages of degeneration, the expression and number of cells immunopositive for m-calpain, μ-calpain and calpastatin were significantly higher. Further finding showed that anti-GVA-reactive aggrecan fragments were significantly higher in discs at advanced compared with early stages of degeneration. Herniated disc samples showed stronger expression and more cells immunopositive for calpains, calpastatin and GVA in the nucleus pulposus than in the annulus fibrous.

CONCLUSIONS

The expression of calpains, together with m-calpain-induced degradation products of extracellular matrix, was correlated with the degree of disc degeneration in human IVD tissue. These findings suggest that calpains may be involved in IVD degeneration via proteoglycan (PG) cleavage.

Interleukin-10 may participate in regulating trophoblast invasion in human placentae throughout gestation

PROBLEM

A successful human pregnancy requires cytotrophoblasts from the fetal portion of the placenta to adopt tumor-like properties. But unlike tumor metastasis, cytotrophoblast invasion is highly regulated both spatially and temporally. The mechanisms that regulate human trophoblast invasion are understood poorly.

METHOD OF STUDY

With a view to obtain some findings on the mechanisms that regulate human trophoblast invasion, we applied the semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) method to compare the expression of invasion-associated genes in cytotrophoblasts isolated from first- and third-trimester placental tissues.

RESULTS

In trophoblast cells of first-trimester pregnancy, the mRNA contents of matrix metalloproteinase (MMP)-9 and urokinase-type plasminogen activator (uPA) were higher than that in the third-trimester cytotrophoblasts, while no difference of MMP-2 mRNA expression level was found between trophoblastic cells of different gestational ages. The expression level of plasminogen activator inhibitors-1 mRNA in first-trimester cytotrophoblasts was shown to be much lower than that in trophoblast cells prepared from third-trimester placental tissues. Furthermore, expression of both tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 in cytotrophoblasts were significantly up-regulated in third-trimester when compared with the first-trimester of pregnancy. To further investigate the factors that caused the change of invasion-associated genes expression in trophoblast cells, we found that interleukin-10 (IL-10) could decrease the content of MMP-9 mRNA in cytotrophoblasts of first-trimester gestation, and the magnitude of suppression increased with increasing IL-10 concentration.

CONCLUSION

The gradually reduced trophoblast invasion with gestational weeks might be on account of the change of proteolytic enzymes/activator/inhibitor genes expression. IL-10 could be one of the factors participating in the regulation of trophoblast invasion during gestational process.

Secretion of toxic oxygen products by macrophages: regulatory cytokines and their effects on the oxidase

We are attempting to identify cytokines that regulate macrophage secretion of reactive oxygen intermediates (ROI) and to analyse the biochemical basis of their effects. In both humans and mice, interferon-gamma (IFN-gamma) appears to be the chief factor secreted by clonally unselected lymphocytes that enhances macrophage oxidative metabolism and antiprotozoal activity. In vivo administration of recombinant IFN-gamma enhances the ROI secretory capacity of monocytes in humans, and the secretion of ROI and killing of protozoa by peritoneal macrophages in mice. A protein secreted by murine tumours and certain non-malignant cells exerts opposing effects. This macrophage deactivation factor (MDF) both blocks the induction of activation by IFN-gamma and reverses pre-existent activation. MDF action is non-toxic and selective, suppressing the secretion of ROI, killing of intracellular protozoa, and expression of Ia antigen, without inhibiting secretion of several other products, or synthesis of protein, ingestion of particles or adherence to culture vessels. The suppressive effect of MDF is reversed over several days after its removal. This reversal is hastened by IFN-gamma. Profound suppression of oxidative metabolism accompanies the differentiation of murine monocytes into Kupffer cells. The capacity of Kupffer cells to secrete ROI and kill intracellular protozoa remains deficient even after exposure to IFN-gamma. Thus, four states of macrophage activation can provisionally be discerned: the transition of mouse peritoneal macrophages from the non-activated to the activated state is accompanied by a ninefold increase in affinity of the superoxide-producing enzyme for NADPH, without a marked increase in cellular Vmax or content of cytochrome b559. The MDF-induced transition of mouse peritoneal macrophages from the activated to the deactivated state is accompanied by both an increase in Km and a decrease in apparent V max of the oxidase. There are no changes in the phorbol myristate acetate receptor number or affinity, glucose transport, NADPH levels, cytochrome b559 content, catalase (EC 1.11.1.6) GSH, GSH peroxidase (EC 1.11.1.9), GSH reductase (EC 1.6.4.2) or myeloperoxidase, consistent with the suppressed ROI secretory capacity and antiprotozoal activity of these cells. The Kupffer cell, whose non-responsiveness to IFN-gamma may mark it as inactivated, appears to lack detectable NADPH oxidase activity, despite the probable presence of cytochrome b559, and in this regard differs from both non-activated and deactivated macrophages.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of Chitin/Chitosan and Their Oligomers/Monomers on Release of Type I Collagenase from Fibroblasts

The effects of chitin/chitosan and their oligomers/monomers on the release of type I collagenase (MMP-1) from fibroblasts were evaluated using adult (adFB) and neonatal human fibroblasts (neFB) by a immunological assay. Release of MMP-1 from adFB increased significantly or tended to increase for all samples, while there was no significant change in MMP-1 levels with neFB. Because the oligomers and monomers of chitin and chitosan influenced MMP-1 activity, it was suggested that the elevated MMP-1 activity would continue until biodegradation of chitin and chitosan was complete.

The matrix metalloproteinase system: changes, regulation, and impact throughout the ovarian and uterine reproductive cycle

The ovary and uterus undergo extensive tissue remodeling throughout each reproductive cycle. This remodeling of the extracellular environment is dependent upon the cyclic hormonal changes associated with each estrous or menstrual cycle. In the ovary, tissue remodeling is requisite for growth and expansion of the follicle, breakdown of the follicular wall during the ovulatory process, transformation of the postovulatory follicle into the corpus luteum, as well as the structural dissolution of the corpus luteum during luteal regression. In the uterus, there is extraordinary turnover of the endometrial connective tissue matrix during each menstrual cycle. This turnover encompasses the complete breakdown and loss of this layer, followed by its subsequent regrowth. With implantation, extensive remodeling of the uterus occurs to support placentation. These dynamic changes in the ovarian and uterine extracellular architecture are regulated, in part, by the matrix metalloproteinase (MMP) system. The MMP system acts to control connective tissue remodeling processes throughout the body and is comprised of both a proteolytic component, the MMPs, and a regulatory component, the associated tissue inhibitors of metalloproteinases. The current review will highlight the key features of the MMPs and tissue inhibitors of metalloproteinases, focus on the changes and regulation of the MMP system that take place throughout the estrous and menstrual cycles, and address the impact of the dynamic tissue remodeling processes on ovarian and uterine physiology.

IL-1 beta induces COX2, MMP-1, -3 and -13, ADAMTS-4, IL-1 beta and IL-6 in human tendon cells

Overuse injuries and trauma in tendon often involve acute or chronic pain and eventual matrix destruction. Anti-inflammatory drugs have been used as a treatment, however, the cellular and molecular mechanisms of the destructive processes in tendon are not clearly understood. It is thought that an inflammatory event may be involved as an initiating factor. Mediators of the inflammatory response include cytokines released from macrophages and monocytes. Interleukin-1 beta (IL-1 beta) is a candidate proinflammatory cytokine that is active in connective tissues such as bone and cartilage. We hypothesized that tendon cells would express receptors and respond to IL-1 beta in an initial "molecular inflammation" cascade, that is, connective tissue cell expression of cytokines that induce matrix destructive enzymes. This cascade results in expression of matrix metalloproteinases (MMPs) and aggrecanases that may lead to matrix destruction. Normal human tendon cells from six patients were isolated, grown to quiescence and treated with human recombinant IL-1 beta in serum-free medium for 16 h. Total RNA was isolated and mRNA expression assessed by semiquantitative RT-PCR. IL-1 beta (1 nM) induced mRNAs for cyclooxygenase 2 (COX2), MMP-1, -3, -13 and aggrecanase-1 as well as IL-1 beta and IL-6, whereas mRNAs for COX1 and MMP-2 were expressed constitutively. The IL-1 beta-treated tendon cells released prostaglandin E(2) (PGE(2)) in the medium, suggesting that the inducible COX2 catalyzed this synthesis. Induction of PGE(2) was detectable at 10 pM IL-1 beta. IL-1 beta also stimulated MMP-1 and -3 protein secretion. Induction of MMP-1 and -3 was detectable at 10 pM IL-1 beta. Post-injury or after some other inciting events, exogenous IL-1 beta released upon bleeding or as leakage of local capillaries may drive a proinflammatory response at the connective tissue cell level. The resulting induction of COX2, MMP-1 and -3 may underscore a potential for nonlymphocyte-mediated cytokine production of MMPs that causes matrix destruction and a loss of tendon biomechanical properties. Endogenous IL-1 beta might contribute to the process through a positive feedback loop by stimulating expression and accumulation of MMPs in the tendon matrix.

Oxidized LDL differentially regulates MMP-1 and TIMP-1 expression in vascular endothelial cells

We have reported recently that oxidized low-density lipoprotein (oxLDL) stimulates matrix metalloproteinase-1 (MMP-1) expression in human vascular endothelial cells. The present study was conducted to examine the effect of oxLDL on expression of Tissue inhibitor of metalloproteinase-1 (TIMP-1), an endogenous inhibitor of MMPs, in human vascular endothelial cells. Our enzyme-linked immunosorbent assay and Northern blot analysis showed that oxLDL inhibited TIMP-1 secretion and expression by human umbilical vein endothelial cells. In contrast, PMA stimulated TIMP-1 expression and secretion. Both oxLDL and PMA increased MMP-1 expression and secretion significantly as previously reported. Inhibition by oxLDL of TIMP-1 expression was also observed in human aortic endothelial cells. Collagenase activity as detected by an enzymatic activity assay demonstrated, as expected, an increase in collagenase activity in the culture medium from oxLDL-treated cells as compared with that from untreated cells. The presented data indicates that oxLDL differentially regulates TIMP-1 and MMP-1 expression, whereas PMA coordinately regulates TIMP-1 and MMP-1 in vascular endothelial cells. The lack of coordination in the secretion of MMP-1 and TIMP-1 induced by oxLDL leads to an increased collagen-degrading activity that may contribute to destabilization of atherosclerotic plaques.

Relaxin positively regulates matrix metalloproteinase expression in human lower uterine segment fibroblasts using a tyrosine kinase signaling pathway

Despite the importance of relaxin to normal parturition in various species and its potential as an etiological agent in preterm delivery in women, knowledge regarding the mechanisms by which relaxin alters cervical connective tissue is extremely limited. An established in vitro model for human pregnancy cervix, human lower uterine segment fibroblasts, was used to determine the effects of relaxin as well as those of progesterone on the expression of matrix metalloproteinases and tissue inhibitor of metalloproteinase-1. The results demonstrate that relaxin is a positive regulator of matrix metalloproteinase expression, as it stimulates the expression of procollagenase protein and mRNA levels, stimulates prostromelysin-1 protein and mRNA levels, and inhibits tissue inhibitor of metalloproteinase-1 protein expression. Stimulation of procollagenase and prostromelysin-1 expression by relaxin does not involve phorbol-12-myristate-13-acetate- sensitive PKCs. Relaxin-stimulated tyrosine phosphorylation of the putative receptor and inhibition by a receptor tyrosine kinase inhibitor suggest that the relaxin receptor is probably a tyrosine kinase receptor. Inhibition of c-Raf protein expression using an antisense oligonucleotide inhibits relaxin regulation of matrix metalloproteinase and tissue inhibitor of metalloproteinase-1, suggesting that a signaling pathway involving c-Raf kinase mediates relaxin action.

Influence of macrophage infiltration of herniated disc tissue on the production of matrix metalloproteinases leading to disc resorption

STUDY DESIGN

Herniated lumbar disc specimens were cocultured with peripheral blood mononuclear cells, and cells isolated from extruded disc were cultured to study the production of matrix metalloproteinases.

OBJECTIVE

To investigate the role of peripheral blood mononuclear cells infiltrating extruded discs and disc-derived cells in the production of matrix metalloproteinases.

SUMMARY OF BACKGROUND DATA

Magnetic resonance imaging analysis of herniated disc patients revealed a progressive decrease in the size of herniated discs. Spontaneous regression of herniated disc is associated with infiltrating macrophages, and matrix metalloproteinases have been implicated in this phenomenon. However, the correlation between infiltrating macrophages and the production of matrix metalloproteinases has received little research attention.

METHODS

Each disc specimen was incubated with homologous peripheral blood mononuclear cells. The numbers of peripheral blood mononuclear cells attached to the surfaces of herniated discs were counted and the culture media was assayed for MMP-3. The cells isolated from herniated discs were incubated with cytokines and the production of matrix metalloproteinases was measured. Total RNA was extracted from herniated discs and RT-PCR was carried out.

RESULTS

Significantly larger numbers of peripheral blood mononuclear cells were attached to the surfaces of extruded discs, and higher amounts of MMP-3 were detected than those of control discs. The culture medium of extruded discs showed higher MMP-1 and MMP-3 production than those from controls. Significant enhancement of MMP-1 and MMP-3 mRNA expression was observed in the disc-derived cells stimulated with cytokines.

CONCLUSION

These results suggest that peripheral blood mononuclear cells infiltrating extruded discs may secrete a variety of biologic materials capable of further recruiting monocytes into herniated discs in an autocrine fashion. Disc cells stimulated with cytokines showed enhanced production of matrix metalloproteinases, which might play an important role in spontaneous regression of disc materials.

Selective induction of tissue inhibitor of metalloproteinase-1 in bleomycin-induced pulmonary fibrosis

Tissue inhibitors of metalloproteinases (TIMPs) are multifunctional proteins that have the capacity to modify cellular activities and to modulate matrix turnover. We demonstrate that TIMP-1 messenger RNA (mRNA) and protein expression are selectively and markedly increased in a murine model of bleomycin-induced pulmonary fibrosis. Northern analysis showed that lung steady-state TIMP-1 mRNA levels increased 14-fold after bleomycin administration compared with control mice. Expression of the genes for TIMP-2, TIMP-3, and interstitial collagenase (matrix metalloproteinase-13) was unaltered in the injured lung. In situ hybridization demonstrated that TIMP-1 gene induction was spatially restricted to areas of lung injury. Metalloproteinase inhibitory activity of relative molecular mass of ~ 21 to 28 kD, corresponding to the molecular weights for TIMP-1 and TIMP-2, was identified in lung extracts of bleomycin-injured mice by reverse zymography. Western analysis demonstrated that TIMP-1 protein levels in bronchoalveolar lavage fluid (BALF) of bleomycin-treated mice increased 220- and 151-fold at Days 4 and 28, respectively, compared with control mice. TIMP-2 immunoreactive protein in the BALF increased 20- and 103-fold relative to controls at Days 4 and 28, respectively. These results demonstrate that TIMP-1 gene expression is selectively increased, and that the expression of TIMP-1 and TIMP-2 is differentially regulated in bleomycin-induced pulmonary fibrosis. The profound and durable increase in TIMP-1 and TIMP-2 proteins suggests an important regulatory role for these antiproteases in the inflammatory and fibrotic responses to bleomycin-induced lung injury.

Fibroblast Enhancement of Tumor Invasion in a Tumor-Host Interface Recapitulated in-vitro

Tumor cells and fibroblasts were isolated from the tumor-host interface of a colon 4047 tumor growing subcutaneously in a Fischer 344 rat. The populations were co-cultured to recapitulate the tumor-host interface in vitro. The co-cultured populations grew in a predictable pattern with tumor cells forming nodules surrounded by fibroblasts. Population dynamic experiments demonstrated the fibroblasts enhanced the growth of the tumor cells but tumor inhibited and ultimately destroyed the fibroblasts. Video microscopic examination of the fibroblasts demonstrated intense membrane ruffling adjacent to the tumor nodules followed by membrane fragmentation and detachment. Immunohistochemical staining for gelatinase A was markedly positive within the fibroblasts surrounding the tumor nodules; but negative within the tumor and in fibroblasts when tumor was absent. This technique recapitulates many aspects of the tumor-host interface in vitro and may be a useful model for evaluating several aspects of tumor-host interaction.

Amplification of IL-1 beta-induced matrix metalloproteinase-9 expression by superoxide in rat glomerular mesangial cells is mediated by increased activities of NF-kappa B and activating protein-1 and involves activation of the mitogen-activated protein kinase pathways

The modulation of cell signaling by free radicals is important for the pathogenesis of inflammatory diseases. Recently, we have shown that NO reduces IL-1beta-induced matrix metalloproteinase (MMP-9) expression in glomerular mesangial cells (MC). Here we report that exogenously administrated superoxide, generated by the hypoxanthine/xanthine oxidase system (HXXO) or by the redox cycler 2, 3-dimethoxy-1,4-naphtoquinone, caused a marked amplification of IL-1beta-primed, steady state, MMP-9 mRNA level and an increase in gelatinolytic activity in the conditioned medium. Superoxide generators alone were ineffective. Cytokine-induced steady state mRNA levels of TIMP-1, an endogenous inhibitor of MMP-9, were affected similarly by HXXO. Transient transfection of rat mesangial cells with 0.6 kb of the 5'-flanking region of the rat MMP-9 gene proved a transcriptional regulation of MMP-9 expression by superoxide. HXXO augmented the IL-1beta-triggered nuclear translocation of p65 and c-Jun and, in parallel, increased DNA binding activities of NF-kappaB and AP-1. Mutation of either response element completely prevented MMP-9 promoter activation by IL-1beta. Moreover, specific inhibitors of the classical extracellular signal-regulated kinase (ERK) pathway and p38 mitogen-activated protein kinase (MAPK) cascade, partially reversed the HXXO-mediated effects on MMP-9 mRNA levels, thus demonstrating involvement of ERKs and p38 MAPKs in MMP-9 expression. Furthermore, IL-1beta-triggered phosphorylation of all three MAPKs, including p38-MAPK, c-Jun N-terminal kinase, and ERK, was substantially enhanced by superoxide. Our data identify superoxide as a costimulatory factor amplifying cytokine-induced MMP-9 expression by interfering with the signaling cascades leading to the activation of AP-1 and NF-kappaB.

Collagenase induction promotes mouse tumorigenesis by two independent pathways

Although progress has been made in the understanding of the role of metalloproteinases in tumor progression during metastasis, little is known about their contributions, if any, to tumor formation. Accumulating evidence identified an increased presence of several matrix metalloproteinases in human cancers, but the precise role for interstitial collagenase in tumor formation or progression has not been well defined. Transient induction of collagenase was observed in wild-type mouse skin after treatment with the tumor-promoting agents 12-O-tetradecanoylphorbol-13-acetate (TPA) and chrysarobin, which promote tumorigenesis through protein kinase C-dependent and -independent pathways, respectively. Transgenic mice that constitutively express interstitial collagenase within the epidermis of the skin have an increased susceptibility to tumorigenesis and produced tumors at lower doses of TPA as compared with wild-type mice. Similarly, the transgenic mice showed increased tumorigenesis when promoted with chrysarobin. These results demonstrate that collagenase overexpression can contribute to tumorigenesis via protein kinase C-dependent and -independent pathways. Significantly, compared with wild-type mice, the transgenic mice demonstrated an elevated expression of c-fos in the skin at baseline, before tumor promotion, suggesting a molecular mechanism for the increased tumor susceptibility in collagenase transgenic mice. These findings further support the importance of MMP deregulation in tumorigenesis and suggest that the role of MMP family members is not limited to metastasis but may also contribute to initial tumor development.

NF-Y and Sp1 cooperate for the transcriptional activation and cAMP response of human tissue inhibitor of metalloproteinases-2

The balance between matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) is a key determinant in the homeostasis of the extracellular matrix. We have identified two cis-acting elements involved in the transcriptional regulation of TIMP-2. The first is an inverted CCAAT box located at position -73 to -69 in the TIMP-2 promoter that binds the transcription factor NF-Y. The second is a GAGGAGGGGG motif located at position -107 to -98, that binds the transcription factors Sp1 and Sp3. NF-Y and Sp1 cooperate for the basal transcription activity of the promoter. We then determined that TIMP-2 is transcriptionally up-regulated by cAMP analogs. Up-regulation of TIMP-2 by dibutyryl cAMP is a delayed response that requires de novo protein synthesis and does not affect RNA stability. The NF-Y and the Sp1 binding site are both involved in cAMP-dependent up-regulation of TIMP-2. Whereas NF-Y is essential for cAMP mediated regulation, Sp1 alone is not sufficient but enhances the activity of NF-Y. Dibutyryl cAMP has no effect on the expression of MMP-2 and MMP-9 and switches the MMP-TIMP balance in favor of the inhibitor.

Increased production of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 by inflamed mucosa in inflammatory bowel disease

Inflammatory bowel diseases (IBD) are characterized by a sustained inflammatory cascade that gives rise to the release of mediators capable of degrading and modifying bowel wall structure. Our aims were (i) to measure the production of matrix metalloproteinase-3 (MMP-3), and its tissue inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), by inflamed and uninflamed colonic mucosa in IBD, and (ii) to correlate their production with that of proinflammatory cytokines and the anti-inflammatory cytokine, IL-10. Thirty-eight patients with IBD, including 25 with Crohn's disease and 13 with ulcerative colitis, were included. Ten controls were also studied. Biopsies were taken from inflamed and uninflamed regions and inflammation was graded both macroscopically and histologically. Organ cultures were performed for 18 h. Tumour necrosis factor-alpha (TNF-alpha), IL-6, IL-1beta, IL-10, MMP-3 and TIMP-1 concentrations were measured using specific immunoassays. The production of both MMP-3 and the TIMP-1 were either undetectable or below the sensitivity of our immunoassay in the vast majority of uninflamed samples either from controls or from those with Crohn's disease or ulcerative colitis. In inflamed mucosa, the production of these mediators increased significantly both in Crohn's disease (P < 0.01 and 0.001, respectively) and ulcerative colitis (P < 0.001 and 0.001, respectively). Mediator production in both cases was significantly correlated with the production of proinflammatory cytokines and IL-10, as well as with the degree of macroscopic and microscopic inflammation. Inflamed mucosa of both Crohn's disease and ulcerative colitis show increased production of both MMP-3 and its tissue inhibitor, which correlates very well with production of IL-1beta, IL-6, TNF-alpha and IL-10.

Platelet-activating factor induces an imbalance between matrix metalloproteinase-1 and tissue inhibitor of metalloproteinases-1 expression in human uterine cervical fibroblasts

Platelet-activating factor (PAF) is involved in such reproductive processes as parturition. We investigated the effect of PAF on the expression of matrix metalloproteinase-1 (MMP-1) and that of tissue inhibitor of metalloproteinases-1 (TIMP-1) in human uterine cervical fibroblasts. Uterine cervical tissue was obtained from patients who underwent cesarean section at term. Collagenase-dispersed fibroblasts were cultured and used in the experiments. PAF receptor was identified in the uterine cervical fibroblasts by use of reverse transcription-polymerase chain reaction and Southern blot analysis. Northern blot analysis showed that PAF increased the expression of MMP-1 mRNA in a time-dependent manner, whereas expression of TIMP-1 mRNA was not affected by PAF. Concentration of MMP-1 protein in the PAF-treated culture media significantly exceeded that in control cultures. The PAF-induced production of MMP-1 protein was abolished by treatment with WEB 2170, a specific PAF receptor antagonist. Results suggest that PAF may accelerate collagenolysis in the human uterine cervix by inducing an imbalance in the activity between MMP-1 and TIMP-1, thus contributing to the cervical ripening during parturition.

Nitric oxide modulates expression of matrix metalloproteinase-9 in rat mesangial cells

Nitric oxide modulates expression of matrix metalloproteinase-9 in rat mesangial cells.

BACKGROUND

High-output levels of nitric oxide (NO) are produced by rat mesangial cells (MCs) in response to proinflammatory cytokines such as interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) by the inducible isoform of NO synthase (iNOS). We tested modulatory effects of NO on the expression and activities of matrix metalloproteinases-9 and -2 (MMP-9 and MMP-2), respectively. Temporal and spatial expression of these MMPs and their specific inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), seems to be critical in the extensive extracellular matrix (ECM) remodeling that accompanies sclerotic processes of the mesangium. Methods and Results. Using the NO donors S-Nitroso-N-acetyl-D,L-penicillamine (SNAP) and DETA-NONOate, we found strong inhibitory effects of NO mainly on the IL-1beta-induced MMP-9 mRNA levels. NO on its own had only weak effects on the expression of MMP-9 and MMP-2. The addition of the NOS inhibitor NG-monomethyl L-arginine (L-NMMA) dose dependently increased steady-state mRNA levels of cytokine-induced MMP-9, suggesting that endogenously produced NO exerts tonic inhibition of MMP-9 expression. MMP-9 activity in conditioned media from MCs costimulated with IL-1beta and NO donor contained less gelatinolytic activity than media of cells treated with IL-1beta alone. Exogenously added NO did not alter gelatinolytic activity of MMP-9 in cell-free zymographs. The expression levels of TIMP-1 were affected by NO similarly to the expression of MMP-9.

CONCLUSION

We conclude that NO modulates cytokine-mediated expression of MMP-9 and TIMP-1 in rat MCs in culture. Our results provide evidence that NO-mediated attenuation of MMP-9 gelatinolytic activity is primarily due to a reduced expression of MMP-9 mRNA, and not the result of direct inhibition of enzymatic activity.

Purification and embryotropic roles of tissue inhibitor of metalloproteinase-1 in development of "HanWoo" (Bos taurus coreanae) oocytes co-cultured with bovine oviduct epithelial cells

This study was conducted to purify a tissue inhibitor of metalloproteinase (TIMP)-1 in a serum-free medium conditioned with bovine oviduct epithelial cells (BOEC) and to evaluate its effect on development of "HanWoo" (Bos taurus coreanae) embryos to the blastocyst stage. In the first study using SDS-PAGE electrophoresis, the presence of 32 kDa proteins, which contains TIMP-1, was detected in the medium conditioned with BOEC, and TIMP-1 was then purified from the medium by gel filtration and HPLC techniques. When examined TIMP-1 secretion, fluorescent foci indicating the secretion of TIMP-1 were found after stained BOEC with fluorescein isothiocyanate. In the next experiment, two-cell embryos derived from in vitro-fertilization were cultured in a serum-free medium, to which 0, 1.25, 2.5 or 5 microg/ml of purified TIMP-1 was supplemented. More (P<0.05) embryos developed to the morula and blastocyst stages after the addition of 2.5 microg/ml to culture medium than after no addition. In conclusion, our data indicate that BOEC secrete TIMP-1 and this glycoprotein promotes the prehatched development of "HanWoo" embryos derived from in vitro-fertilization.

Collagenolysis in the lower uterine segment during parturition at term: correlations with stage of cervical dilatation and duration of labor

OBJECTIVE

The objective of this study was to quantify the extent of neutrophil infiltration and the concentrations of enzymes involved in collagenolysis in the lower uterine segment in relation to the degree of cervical dilatation and the duration of labor.

STUDY DESIGN

Biopsy specimens of the lower uterine segment were obtained from 62 women undergoing cesarean section at term. The number of extravascular neutrophils was assessed with enzyme histochemical evaluation, and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 by were assessed by enzyme-linked immunosorbent assay.

RESULTS

The neutrophil count and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 increased with increasing cervical dilatation. At >6 cm the neutrophil count and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 were significantly higher than at <2 cm. An association with the duration of labor was found for the neutrophil count and the concentrations of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinases-1. Multiple linear regression analysis showed that the degree of cervical dilatation is more closely related to the 4 laboratory parameters investigated than to the duration of labor.

CONCLUSION

The findings support the hypothesis that local changes (ie, collagenolysis) in the lower uterine segment unrelated to uterine activity play a crucial role in cervical dilatation at term.

Cyclosporin A regulates interleukin-1beta and interleukin-6 expression in gingiva: implications for gingival overgrowth

BACKGROUND

Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA); however, the cellular mechanisms remain poorly understood. CsA's immunosuppressant properties involve the regulation of synthesis and cellular response to cytokines. A CsA-induced alteration in the cytokine profile within gingival tissue could provide a mechanism for gingival hyperplasia. The aim of this study was to investigate the effects of CsA on the production of 2 cytokines - interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) - by both gingival fibroblasts and peripheral blood mononuclear cells (PBMC).

METHODS

Cells were stimulated for 24 hours in the presence of CsA over a concentration range of 100 to 2,000 ng/ml and the resultant cytokine production determined by ELISA. In addition, levels of both cytokines within normal, inflamed, and overgrown gingival tissue were determined.

RESULTS

CsA inhibited IL-6 production by gingival fibroblasts in a dose-dependent manner. In contrast, at a concentration of 2,000 ng/ml, CsA stimulated IL-6 production by PBMC (P <0.05). Fibroblasts derived from overgrown gingiva produced significantly higher levels of IL-6 than their normal counterparts (P <0.05). CsA inhibited IL-1beta production by PBMC over the whole concentration range (P <0.05). IL-1beta was not found in measurable quantities in any of the fibroblast cultures. Levels of IL-6 extracted from overgrown gingival tissue were significantly higher than in inflamed or normal tissue. In contrast IL-1beta levels in overgrown tissue were not statistically significantly greater than those in inflamed tissue.

CONCLUSIONS

These results show that CsA does regulate cytokine expression in gingival tissue. This effect may play an important role in the pathogenesis of CsA-induced gingival overgrowth.

Novel implications in the development of endometriosis: biphasic effect of macrophage activation on peritoneal tissue expression of tissue inhibitor of metalloproteinase-1

PROBLEM

Elevated levels of activated macrophages are associated with endometriosis, but their role in the etiology of the disease is uncertain. The current study was undertaken to examine whether activated macrophages could modulate peritoneal tissue expression of the tissue inhibitor of metalloproteinase-1 (TIMP-1), which may play a role in the development of endometriosis.

METHOD OF STUDY

Female mice were treated with the macrophage activator lipopolysaccharide (LPS), and peritoneum TIMP-1 mRNA was examined by Northern blot analysis.

RESULTS

LPS induced a dose-dependent increase (P < 0.05) in TIMP-1 mRNA expression at levels of 1 microgram (70.0% +/- 5.8% greater than the control), 10 micrograms (83.0% +/- 12.0% greater than the control), and 25 micrograms (100.0% +/- 10.0% greater than the control). In contrast, the administration of 50 micrograms of LPS resulted in a decrease in TIMP-1 mRNA expression below baseline levels (18.0% +/- 6.0% less than the control values).

CONCLUSIONS

Activated macrophages and/or their products modulate peritoneum TIMP-1 expression. These data suggest that, in addition to their phagocytotic role in the peritoneal cavity, these immune cells also may play a novel role in influencing the ability of the peritoneum to regulate tissue/cell invasion and in the development of endometriosis through TIMP-1 expression.

Interleukin (IL)-6 and its soluble receptor induce TIMP-1 expression in synoviocytes and chondrocytes, and block IL-1-induced collagenolytic activity

To define the potential role of interleukin-6 (IL-6) and its soluble receptor alpha in cartilage metabolism, we analyzed their effects on tissue inhibitor of metalloproteases (TIMP) synthesis by synoviocytes and chondrocytes. TIMP-1 production by isolated human articular synovial fibroblasts and chondrocytes, stimulated by IL-6 and/or its soluble receptor, was first assayed by specific enzyme-linked immunosorbent assay; the slight stimulatory effect of IL-6 on TIMP-1 production by both types of cells was markedly amplified by the addition of soluble receptor, the maximal secretion being observed only at 96 h. TIMP-1 mRNA expression, determined by ribonuclease protection assay, was induced by IL-6 together with its soluble receptor, but TIMP-2 and -3 mRNAs were not affected by these factors. A specific neutralizing antibody abolished the effects of the soluble receptor. Finally, supernatant from synoviocytes stimulated by IL-6 plus its soluble receptor blocked almost completely the collagenolytic activity of supernatant from IL-1-induced synoviocytes. These observations indicate that IL-6 and its soluble receptor have a protective role in the metabolism of cartilage. Given the high levels of soluble receptor in synovial fluid and the marked induction of IL-6 by IL-1 or TNF-alpha, it is likely that IL-6 and its soluble receptor are critical in controlling the catabolic effects of pro-inflammatory cytokines.

Immunolocalization of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human subconjunctival tissues

PURPOSE

To evaluate the roles of fibroblast proteins in the remodeling of the subconjunctival connective tissue, we immunohistochemically assessed the expression of matrix metalloproteinases (MMP)-1 and -2, and the tissue inhibitors of matrix metalloproteinases (TIMP)-1 and -2 in cultured human subconjunctival fibroblasts and in normal and healing human subconjunctival connective tissue.

METHODS

Cultured fibroblasts derived from human subconjunctival connective tissue and surgical specimens of normal and healing conjunctiva were immunostained with monoclonal antibodies directed against human MMPs and TIMPs and examined by light and electron microscopy.

RESULTS

In the cultured fibroblasts, MMP-1 and TIMP-1 antibodies stained the cytoplasm in a fine granular pattern, suggesting localization of those proteins in the endoplasmic reticulum (ER) and Golgi apparatus. Antibodies to MMP-2 and TIMP-2 reacted with fibroblast cytoplasm in a granular pattern. Electron microscopy of those fibroblasts revealed MMP-1 and TIMP-1 immunoreactivity in the ER cisternae or on the membrane of the ER. In surgical samples, MMP-1 and TIMP-1 were immunohistochemically detected in healing subconjunctival tissue, but not in conjunctival epithelium or normal subconjunctival tissue.

CONCLUSIONS

MMPs and TIMPs may be involved in remodeling of subconjunctival connective tissue and in fibroblast population after surgical interventions. These proteins may play a crucial role in the post-operative fibrotic process occurring during scar formation in subconjunctival tissue.

Oncostatin M stimulates c-Fos to bind a transcriptionally responsive AP-1 element within the tissue inhibitor of metalloproteinase-1 promoter

Tissue inhibitor of metalloproteinases-1 (TIMP-1) can be regulated by gp130 cytokines such as IL-6 and oncostatin M (OSM). Polymerase chain reaction deletion analysis of the murine TIMP-1 proximal promoter in chloramphenicol acetyltransferase reporter gene constructs identified an AP-1 element (-59/-53) that allows maximal responsiveness to OSM in HepG2 cells. Fos and Jun nuclear factors bound constitutively to this site as identified by supershift analysis in electrophoretic mobility shift assays, and oncostatin M (but not IL-6) induced an additional "complex 2" that contained c-Fos and JunD. OSM stimulated a rapid and transient increase in c-Fos mRNA and nuclear protein that coincided with complex 2 formation. Phorbol 13-myristate 12-acetate could also induce c-Fos but could not regulate the TIMP-1 reporter gene constructs. Transfection studies also showed that 3'-deletion of sequences downstream of the transcriptional start site (+1/+47) markedly reduced OSM -fold induction. Nuclear factors bound to SP1 and Ets sequences were detected, but were not altered upon OSM stimulation. Although OSM and IL-6 induced STAT (signal transducers and activators of transcription) factors to bind a high affinity Sis-inducible element DNA probe, binding to homologous TIMP-1 promoter sequences was not detected. Thus, OSM (but not IL-6) stimulates c-Fos, which participates in maximal activation of TIMP-1 transcription, likely in cooperation with other factors such as SP1 or as yet unidentified mechanisms involving the +1 to +47 region of the promoter.

Replacement of conserved cysteines in human tissue inhibitor of metalloproteinases-1

Tissue inhibitor of metalloproteinases-1 (TIMP-1) is resistant to extremes of temperature and pH. This is thought to be due in part to the presence of six sulfhydryl bridges presumed to maintain the structural integrity of the molecule. As part of a study looking at structure-function relationships, a number of the conserved cysteine residues in TIMP-1 were targeted for replacement with serine. Single and double replacements of these conserved cysteines, as well as replacements around these cysteines, were expressed using a vaccinia virus system and analyzed for functional and structural competence. Analysis by circular dichroism indicated that these mutants maintained secondary structures similar to those of wild-type TIMP-1. Trypsin susceptibility experiments indicated that the tertiary structure of the mutants had not been drastically changed. Analysis of functional competence demonstrated that there were significant changes in some of these mutants. Assays using collagen fibrils or gelatin as substrates indicated that the double mutant C1S/C70S, but not C3S/C99S, had lost inhibitory activity against human fibroblast-type collagenase (FIB-CL) and at high concentrations only had slight activity against Mr 72,000 gelatinase (Mr 72,000 gelatinase). Kinetic analysis of TIMP-1 inhibition of FIB-CL cleavage of a peptide substrate indicated that mutants C1S/C70S, C3S/C99S, and CEEC --> CQQC retained their ability to inhibit FIB-CL in a manner similar to wild-type TIMP-1, while mutants C1S and C70S showed little inhibitory activity. The mutants C99S and C137S could also inhibit FIB-CL cleavage of the peptide substrate. The results indicated that the degree of inhibition by the TIMP-1 mutants varied somewhat depending on the choice of substrates. Interestingly, replacing both cysteines from a disulfide bond in the wild-type molecule resulted in a more competent inhibitor than either of the single site "parent" mutations. Taken together, these experiments indicate that TIMP-1 can be rendered inactive by the loss of a single cysteine.

Transforming growth factor-beta regulation of bone morphogenetic protein-1/procollagen C-proteinase and related proteins in fibrogenic cells and keratinocytes

Transforming growth factor-beta1 (TGF-beta1) induces increased extracellular matrix deposition. Bone morphogenetic protein-1 (BMP-1) also plays key roles in regulating vertebrate matrix deposition; it is the procollagen C-proteinase (PCP) that processes procollagen types I-III, and it may also mediate biosynthetic processing of lysyl oxidase and laminin 5. Here we show that BMP-1 is itself up-regulated by TGF-beta1 and that secreted BMP-1, induced by TGF-beta1, is either processed to an active form or remains as unprocessed proenzyme, in a cell type-dependent manner. In MG-63 osteosacrcoma cells, TGF-beta1 elevated levels of BMP-1 mRNA approximately 7-fold and elevated levels of mRNA for mammalian tolloid (mTld), an alternatively spliced product of the BMP1 gene, to a lesser extent. Induction of RNA was dose- and time-dependent and cycloheximide-inhibitable. Secreted BMP-1 and mTld, induced by TGF-beta1 in MG-63 and other fibrogenic cell cultures, were predominantly in forms in which proregions had been removed to yield activated enzyme. TGF-beta1 treatment also induced procollagen N-proteinase activity in fibrogenic cultures, while expression of the procollagen C-proteinase enhancer (PCPE), a glycoprotein that stimulates PCP activity, was unaffected. In contrast to fibrogenic cells, keratinocytes lacked detectable PCPE under any culture conditions and were induced by TGF-beta1 to secrete BMP-1 and mTld predominantly as unprocessed proenzymes.

The C-terminal domain of tissue inhibitor of metalloproteinases-2 is required for cell binding but not for antimetalloproteinase activity

We have generated a C-terminally-truncated form of recombinant tissue inhibitor of metalloproteinases-2 (designated rTIMP-2 delta) in which the region of the inhibitor extending from residue 128 to 194 and including 3 of the 6 disulfide bonds is deleted. rTIMP-2 and rTIMP-2 delta had similar inhibitory activities toward interstitial collagenase and inhibited the activation of the precursor form of matrix metalloproteinase-2 (proMMP-2). rTIMP-2 also bound with high affinity (Kd 0.99 nM) to HT1080 human fibrosarcoma cells treated with 12-O-tetradecanoyl-phorbol-13-acetate. However deletion of the C-terminal domain of TIMP-2 significantly lowered the cell surface binding affinity, with competition experiments indicating a 2 order of magnitude difference between rTIMP-2 and rTIMP-2 delta in the concentrations needed to displace 125I-labeled rTIMP-2 binding. These data indicate that the C-terminal domain of TIMP-2 is not required for the antimetalloproteinase activity but plays a major role in the high affinity cell surface binding of the inhibitor.

Tissue inhibitor of metalloproteinase-1 in the liver of patients with chronic liver disease

BACKGROUND/AIMS

Tissue inhibitor of metalloproteinase (TIMP)-1 is an important regulator of matrix metalloproteinase activity. To clarify the changes in TIMP-1 in diseased livers, we measured TIMP-1 concentrations in liver tissue samples from patients with chronic liver disease. The relationship between serum and liver levels of TIMP-1 was also examined in some patients.

METHODS

The subjects were 68 patients who underwent liver biopsy. The liver TIMP-1 concentration was measured using an enzyme immunoassay after the extraction of TIMP-1 with 2 M guanidine.

RESULTS

As compared with the controls (n=10), the liver TIMP-1 level was increased 2.2-fold in the 24 chronic active hepatitis 2A patients, 2.9-fold in the 10 chronic active hepatitis 2B patients and 4.1-fold in the six liver cirrhosis patients, but no significant increase was observed among the 18 chronic persistent hepatitis patients. The liver TIMP-1 levels were closely correlated with the histological degrees of periportal necrosis, portal inflammation, and liver fibrosis. When the localization of TIMP-1 was examined immunohistochemically, TIMP-1 was stained mainly in hepatocytes, and the intensity was stronger in the livers of chronic active hepatitis and liver cirrhosis patients than in those of the chronic persistent hepatitis patients. The serum TIMP-1 and liver TIMP-1 levels were significantly correlated, indicating that serum TIMP-1 could reflect the change of liver TIMP-1 in patients with chronic liver disease.

CONCLUSION

Liver TIMP-1 concentration increases with progression of the liver disease, when the degradation of extracellular matrix proteins is decreased, resulting in the development of liver fibrosis.

Cytokines modulate routes of collagen breakdown. Review with special emphasis on mechanisms of collagen degradation in the periodontium and the burst hypothesis of periodontal disease progression

In this paper, we review recent work on collagen degradation, 2 main routes of breakdown are described and their relevance during healthy and inflammatory conditions of the periodontium is discussed. Special attention is paid to the possible role of cytokines, in particular interleukin 1 (IL-1) and transforming growth factor beta (TGF-beta), on the modulation of collagen phagocytosis and metalloproteinase production. IL-1 has been shown to have a dual function in collagen digestion. It inhibits the intracellular phagocytic pathway, but at the same time, it strongly promotes extracellular digestion by inducing the release of collagenolytic enzymes like collagenase. TGF-beta has an opposite effect on both pathways and antagonizes IL-1. Collagenase is released in an inactive form, and a considerable fraction of the proenzyme may become incorporated in the extracellular matrix. This reservoir of latent enzyme can be activated (for instance by plasmin), leading to a sudden and extensive breakdown of the collagenous fibre meshwork. It is suggested that this phenomenon may also take place during progressive periodontitis and could explain an episodic nature of collagenolysis, clinically resulting in bursts of attachment loss (burst hypothesis).

Tissue inhibitor of metalloproteinase 1 (TIMP-1) may be an autocrine growth factor in scleroderma fibroblasts

In scleroderma (systemic sclerosis, SSc), an autoimmune disorder in which excessive extracellular matrix is deposited in skin and internal organs, one of the suggested contributory factors to the development of fibrosis is a decrease in collagenase activity that may be related to levels of serum tissue inhibitors of metalloproteinases 1 (TIMP-1). We recently reported that the serum TIMP-1 levels in SSc patients were elevated compared with normal controls. To determine the biologic significance of TIMP-1 in SSc, we compared the proliferative effects of TIMP-1 between normal and SSc fibroblasts. TIMP-1 showed significant mitogenic activity for both normal and SSc fibroblasts. The mitogenic responses to TIMP-1 (33-100 ng/ml) in SSc fibroblasts, however, were significantly greater than those in normal controls and were completely neutralized in the presence of anti-TIMP-1 IgG. Moreover, anti-TIMP-1 IgG partially but significantly blocked the basal mitogenic activities of SSc fibroblasts. SSc fibroblasts produced increased amounts of TIMP-1 relative to normal fibroblasts, as confirmed by western blotting, ELISA, and RT-PCR techniques. In contrast, transforming growth factor beta1 (TGF-beta1) upregulated TIMP-1 production in normal fibroblasts but not in SSc fibroblasts with elevated spontaneous secretion of TIMP-1. These observations suggest that TIMP-1 may play an important role as an autocrine growth factor in the fibrotic process in SSc.

The matrix metalloproteinases and their inhibitors in pancreatic cancer. From molecular science to a clinical application

The matrix metalloproteinases (MMPs) and their tissue-specific inhibitors (TIMPs) are described and their roles in tumor invasion and metastasis are reviewed. The expression and activity of the MMPs and TIMPs in pancreatic cancer is reported and illustrated with immunohistochemistry and in situ hybridization. The role of MMP inhibitors (MMPIs) is reviewed in vivo and the use of novel MMPIs, e.g., BB94 (Batimastat) and BB2516 (Marimastat); in animal experiments are also described. Finally, the preliminary results from a phase 2 trial of BB2516 (Marimastat) in pancreatic cancer are reported.

Factors affecting IL-1-mediated collagen metabolism by fibroblasts and the pathogenesis of periodontal disease: a review of the literature

Fibroblasts have been studied extensively for their contribution to connective tissue destruction in diseases where the metabolism of extracellular matrix components plays an essential part in their pathogenesis. A considerable dissolution, especially of collagen fibrils, is a well-known characteristic of the periodontal ligament and the gingival connective tissue in microbial-induced periodontal disease. Fibroblasts, responsible for the assembly of the extracellular matrix, are capable of responding directly to oral microbial challenges or indirectly, following activation of the host immune response, and can alter the composition of connective tissue in several ways: synthesis of inflammatory mediators, their receptors and antagonists; fibroblast proliferation; collagen synthesis; phagocytosis of collagen fibrils; and synthesis of proteolytic enzymes, including matrix metalloproteinases and their corresponding inhibitors. The contributions of these cellular fibroblastic properties to the pathogenesis of periodontal disease are reviewed in the context of the cytokine, interleukin-1, as the inflammatory regulator.

Angiotensin II induces TIMP-1 production in rat heart endothelial cells

Angiotensin II (AII) was found to upregulate tissue inhibitor of metalloproteineses-1 (TIMP-1) gene expression in rat heart endothelial cells in a dose and time-dependent manner. The maximal stimulation of TIMP-1 mRNA was achieved by 2 h after the addition of AII. This effect was blocked by losartan, an AT1 receptor antagonist and by calphostin C, a protein kinase C inhibitor. Addition of cycloheximide superinduced and actinomycin D abolished the induction. These results suggest that AII stimulates TIMP-1 production by a protein kinase C dependent pathway which is dependent upon de novo RNA synthesis. Immunoprecipitation experiment showed an enhanced band of 28 kDa from the conditioned medium of AII-treated cultures. Immunoblot analysis revealed that TIMP-1 was detectable in the conditioned medium 4 h after AII stimulation. Since endothelial cells line the blood vessels and sense the rise in AII associated with hypertension, the TIMP-1 released by these cells may provide an initial trigger leading to cardiac fibrosis in angiotensin-renin dependent hypertension.

Independent regulation of matrix metalloproteinases and plasminogen activators in human fibrosarcoma cells

Serine proteases and matrix metalloproteinases have been shown to often cooperate in multiple physiological and pathological processes associated with changes in the extracellular matrix (ECM). We have examined the interaction between the plasminogen activator (PA)-plasmin system and matrix metalloproteinases (MMPs) in HT1080 human fibrosarcoma cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA). While TPA treatment evoked a temporary increased expression of urokinase type PA (uPA), the production of both types of human plasminogen activator inhibitors (PAI) was induced and sustained over 12 h by TPA treatment shifting the protease-protease inhibitors balance in favor of the inhibitors. TPA treatment of HT1080 cells induced the expression of interstitial collagenase (MMP-1) and increased the expression of gelatinase B (MMP-9), tissue inhibitor of metalloproteinases-1 (TIMP-1), and MT-MMP, a membrane-bound activator of progelatinase A (proMMP-2), while MMP-2 and TIMP-2 expression were decreased. Increased MT-MMP expression by TPA treatment was associated with increased activation of proMMP-2. These data show that the regulation of PA-plasmin and metalloproteinase and their specific inhibitors is uncoordinated. In addition, inhibition of the PA-plasmin system by PAI-2 or aprotinin did not prevent the activation of proMMP-2 by TPA, suggesting that plasmin is not involved in MT-MMP-mediated activation of proMMP-2.

Ontogenies of messenger RNA encoding tissue inhibitor of metalloproteinases 1 and 2 within bovine periovulatory follicles and luteal tissue

Tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1 and TIMP-2) are important regulators of extracellular matrix remodeling and also possess growth factor activity. The objective of these studies was to characterize TIMP-1 and TIMP-2 mRNA expression by bovine periovulatory follicles/ corpora hemorrhagica (Experiment 1) and luteal tissue (Experiment 2). In Experiment 1, beef heifers (n = 27) were ovariectomized at-16 (n = 6), 0 (n = 5), 8 (n = 3), 16 (n = 4), 24 (n = 4), or 48 (n = 5) hr relative to a gonadotropin-releasing hormone induced gonadotropin surge (40 hr after prostaglandin F2 alpha-induced luteolysis). Total cellular RNA was isolated from the large steroidogenically active follicle or corpus hemorrhagicum obtained from each animal, and the expression of TIMP-1 and TIMP-2 mRNA was subsequently examined by northern and dot blot analysis. The expression of TIMP-1 or TIMP-2 mRNa did not differ in preovulatory follicles collected at -16 vs. 0 hr. Concentrations of both TIMP-1 and TIMP-2 mRNA (picograms per microgram of tissue DNA) were increased (P < 0.05) at 8 hr postgonadotropin surge, had declined to presurge levels by 24 hr (P < 0.05), and were increased (P < 0.05) in corpora hemorrhagica collected at 48 hr after a gonadotropin surge. In Experiment 2, corpora lutea were collected from beef heifers on Days 4, 10, 15 (n = 4 each), or 19 (n = 3) postestrus (Day 0 = estrus). Concentrations of TIMP-1 mRNA (picograms per microgram of tissue DNA) were greater in corpora lutea collected on Day 4 (P < 0.05) vs. Day 10, 15, or 19. Concentrations of TIMP-2 mRNA increased (P < 0.05) from Day 4 to 15 and decreased (P < 0.05) by Day 19. We conclude that: 1) during the periovulatory period, the ontogenies of TIMP-1 and TIMP-2 mRNA expression are similar, whereas 2) during luteal phase, TIMP-1 mRNA expression is maximal during the early luteal phase, whereas concentrations of TIMP-2 mRNA peak during the midluteal phase. TIMP-1 and TIMP-2 may play important roles in the regulation of extracellular matrix remodeling during the periovulatory period and the subsequent luteal phase.

Acidic pH enhances the invasive behavior of human melanoma cells

As a consequence of poor perfusion and elevated acid production, the extracellular pH (pHex) of tumors is generally acidic. Despite this, most in vitro experiments are still performed at the relatively alkaline pHex of 7.4. This is significant, because slight changes in pHex can have profound effects on cell phenotype. In this study we examined the effects of mildly acidic conditions on the in vitro invasive potential of two human melanoma cell lines; the highly invasive C8161, and poorly invasive A375P. We observed that culturing of either cell line at acidic pH (6.8) caused dramatic increases in both migration and invasion, as measured with the Membrane Invasion Culture System (MICS). This was not due to a direct effect of pH on the invasive machinery, since cells cultured at normal pH (7.4) and tested at acidic pH did not exhibit increased invasive potential. Similarly, cells cultured at acidic pH were more aggressive than control cells when tested at the same medium pH. These data indicate that culturing of cells at mildly acidic pH induces them to become more invasive. Since acid pH will affect the intracellular pH (pHin) and intracellular calcium ([Ca2+]in), we examined the effect of these parameters on invasion. While changes in [Ca2+]in were not consistent with invasive potential, the changes in pHin were. While these conditions decrease the overall amount of gelatinases A and B secreted by these cells, there is a consistent and significant increase in the proportion of the activated form of gelatinase B.

Significance of serum tissue inhibitor of metalloproteinases-1 in various liver diseases

BACKGROUND/AIMS

This study was performed to assess the significance of elevated serum tissue inhibitor of metalloproteinases-1 concentration in various liver diseases.

METHODS

Tissue inhibitor of metalloproteinases-1 levels were measured in patients with various liver diseases, and were compared with serum type III procollagen-N-peptide (P III P), type IV collagen and laminin P1 levels, as well as with the histology of liver biopsy specimens.

RESULTS

Mean tissue inhibitor of metalloproteinases-1 levels were significantly higher in subjects with acute viral hepatitis, cirrhosis, alcoholic hepatitis, and alcoholic cirrhosis than in the control group (p < 0.05). Serum tissue inhibitor of metalloproteinases-1 levels in the various liver diseases showed positive correlation with serum type IV collagen, P III P, and laminin P1 levels. Regarding the relationship between tissue inhibitor of metalloproteinases-1 and liver histology, serum tissue inhibitor of metalloproteinases-1 levels correlated with the degree of hepatic fibrosis and inflammation, such as focal necrosis and cell infiltration. Furthermore, elevated serum tissue inhibitor of metalloproteinases-1 levels were especially related to the cell infiltration, focal necrosis, portal fibrosis, and serum type IV collagen level.

CONCLUSIONS

These findings suggest that the measurement of the serum tissue inhibitor of metalloproteinases-1 level in various liver diseases may be useful to estimate the active hepatic fibrogenesis associated with the active inflammatory stage of the liver injury.

Immunohistochemical study of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 human intervertebral discs

STUDY DESIGN

Immunohistologic staining of human intervertebral discs collected at the time of surgery (100 intervertebral discs from 80 patients) and 10 discs collected from 7 cadavers within 12 hours of death was performed using antimatrix metalloproteinase-3 monoclonal antibody and antitissue inhibitor of metalloproteinase-1 monoclonal antibody.

OBJECTIVES

To examine the relationship between matrix destruction and staining for matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 in intervertebral disc degeneration.

SUMMARY OF BACKGROUND DATA

Matrix metalloproteinase-3, which decomposes aggregating proteoglycans, has attracted research attention as a substance contributing to matrix destruction in the articular cartilage and intervertebral disc. However, except for a few in vitro studies, the relationship between matrix destruction of the intervertebral disc and matrix metalloproteinase-3 has been little studied.

METHODS

Immunohistologic staining was performed to examine the relationship between matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 in the intervertebral disc, and the relationship of these two agents to magnetic resonance imaging, radiographic, and surgical findings.

RESULTS

Those cases testing positive for matrix metalloproteinase-3 and negative for tissue inhibitor of metalloproteinase-1 accounted for most of the surgical specimens. The matrix metalloproteinase-3-positive cell ratio was significantly correlated with the magnetic resonance imaging grade of intervertebral disc degeneration, and the matrix metalloproteinase-3-positive cell ratio observed in prolapsed lumbar intervertebral discs was significantly higher than that in nonprolapsed discs. In cervical intervertebral discs, the matrix metalloproteinase-3-positive cell ratio and staining of cartilaginous endplate were correlated with the size of osteophyte formation.

CONCLUSIONS

These findings suggested that intervertebral disc degeneration is caused by disturbance in the equilibrium of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1, and that matrix metalloproteinase-3 contributes to degeneration of the cartilaginous endplate.

Serum tissue inhibitor of metalloproteinases in patients with systemic sclerosis

BACKGROUND

One of the suggested contributory factors to the development of dermal fibrosis is a decrease in collagenase activity, which may be related to levels of serum tissue inhibitors of metalloproteinase-1 (TIMP-1).

OBJECTIVE

The aim of this study was to determine the clinical significance of serum TIMP-1 levels in systemic sclerosis (SSc).

METHODS

We measured serum TIMP-1 concentration in 62 patients with SSc, 11 patients with systemic lupus erythematosus, 14 patients with rheumatoid arthritis, and 22 members of a normal control group. The clinical features of the patients with SSc and elevated TIMP levels were examined.

RESULTS

The mean TIMP-1 level in the patients with SSc was significantly higher than that in the members of the control group or the patients with systemic lupus erythematosus or rheumatoid arthritis. In 44% of the patients with SSc the serum TIMP-1 level was elevated. The mean serum TIMP-1 level in patients with diffuse cutaneous SSc (dSSc) was significantly higher than that in those with limited cutaneous SSc. The patients with dSSc and elevated serum TIMP-1 levels showed a significantly greater incidence of lung fibrosis and anti-topoisomerase I antibody than those with normal serum TIMP-1 levels. The TIMP-1 level and diffusing capacity for carbon monoxide in the patients with SSc were negatively correlated. Increased mitogenic activity on dermal fibroblasts caused by serum from patients with dSSc was partially blocked by anti-TIMP-1 IgG.

CONCLUSIONS

These findings suggest that serum TIMP-1 level is a useful indicator of disease activity in patients with SSc and that TIMP is involved in the pathogenesis of SSc.

Determination of interstitial collagenase (MMP-1) in patients with rheumatoid arthritis

OBJECTIVES

To investigate whether interstitial collagenase (MMP-1) concentration in synovial fluid can be useful as a marker for disease activity in rheumatoid arthritis (RA), to determine the main route by which collagenase degrades the matrix of articular cartilage, and to investigate if an imbalance between metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMP) is responsible for the activity of MMPs in RA.

METHODS

Collagenase concentrations were measured in synovial fluid and paired serum samples using a specific sandwich enzyme linked immunosorbent assay. Collagenase activities were also assayed in synovial fluid samples. Synovial tissues obtained from the same patient were examined by immunohistochemical staining and the numbers of cells expressing collagenase were counted.

RESULTS

Collagenase concentrations in synovial fluid did not correlate with C reactive protein and collagenase levels in serum, but did correlate positively with the degree of synovial inflammation, and increased with increasing numbers of cells identified as expressing collagenase in synovial tissue. Collagenase activities did not correlate with TIMP-1 concentrations, but did correlate strongly with the ratios of collagenase concentration to TIMP-1 (r = 0.73).

CONCLUSION

The collagenase concentration in synovial fluid cannot be used as a marker for systemic disease activity, but can be used as a marker for the degree of synovial inflammation in the joint from which the sample is aspirated. In advanced RA, most of the collagenase is probably produced in synovial lining cells and released into synovial fluid, where it degrades the matrix of articular cartilage. An imbalance between MMP and TIMP may be of importance in the degradation of extracellular matrix of articular cartilage in RA.

Collagenase (MMP-1) and TIMP-1 in destructive corneal disease associated with rheumatoid arthritis

The aim of the study was to immunolocalise interstitial collagenase (MMP-1) and the tissue inhibitor of metalloproteinases (TIMP-1) in ulcerating corneas from patients with rheumatoid arthritis, to determine whether changes in expression are associated with destructive corneal disease. Collagenase was expressed by stromal cells in 8 of 8 ulcerating corneas but was not seen in normal tissue (n = 3). TIMP-1 was abundant throughout the normal stroma, but was much reduced or absent from diseased corneas. Collagenase staining was frequently more intense near the epithelial surface and associated with a cellular infiltrate consisting of activated antigen-presenting cells (HLA-DR+), many of which were macrophages (CD68+) and derived from the epithelium or limbus (S100+). Interstitial collagenase produced by infiltrating macrophages and/or stimulated corneal fibrocytes is probably a major mediator of collagen degradation in rheumatoid corneal ulceration. In addition, reduced levels of TIMP-1 expression are consistent with collagenase activity and tissue destruction. Epithelial-stromal cell interactions and the production of local inflammatory mediators are of major importance in the pathogenesis of corneal destruction, although the precise nature of the antigenic stimulation and/or cellular interactions remains to be elucidated.

Modulation by hypergravity of extracellular matrix macromolecules in in vitro human dermal fibroblasts

In vitro human dermal fibroblasts were submitted to normal gravity (1 g) or to chronic hypergravity (20 g) over a period of 8 days. Changes in organization of extracellular matrix molecules were seen by indirect immunofluorescence. In the fibronectin layer, bundles of fibrils were gathered together leading to a disorganisation of the normal parallel pattern of fibers seen in control cultures. Type I collagen fibrils appeared with wooly outlines in controls whereas thick fibers were closely packed in 20-g cultures. A moderate increase of type III collagen fibril density was observed. No elastic fibers were seen in control or in 20-g cultures. In the culture medium, the release of soluble elastin (ELISA) and type I and III collagens (RIA) was undisturbed. Assays of enzymes involved in the remodeling of extracellular matrix showed an increase of cellular elastase activity (10%) and a decrease of the spontaneously active collagenase. Nevertheless, the total collagenase activity, (activated by trypsin), was increased by up to 30%. These data show a significant rise of the latent collagenase activity and suggest that release of the tissue inhibitor of metalloproteinase (TIMP1) was enhanced by hypergravity.