Päivi Maisi

The in vivo Expression of the Collagenolytic Matrix Metalloproteinases (MMP-2, -8, -13, and -14) and Matrilysin (MMP-7) in Adult and Localized Juvenile Periodontitis

Periodontal inflammation is characterized by irreversible degradation of periodontal ligament collagen fibers leading to loss of tooth attachment. Cultured gingival keratinocytes and fibroblasts express, in vitro, various matrix metalloproteinases (MMPs) which can degrade fibrillar collagens. We hypothesized that several MMPs are also synthesized in vivo by sulcular epithelium, and analyzed the collagenolytic MMPs (MMP-2, -8, -13, and -14) and matrilysin (MMP-7) in gingival tissue specimens and gingival crevicular fluid from adult and localized juvenile periodontitis patients by in situ hybridization, immunohistochemistry, and Western immunoblotting. MMP-2, -7, -8, and -13 were expressed in gingival sulcular epithelium. MMP-7 and -13 were also located in fibroblasts and macrophages, and MMP-8 in neutrophils. MMP-8- and -13-positive cells/mm2 were higher in periodontitis gingiva when compared with healthy control tissue (p < 0.01). In periodontal diseases, gingival sulcular epithelium expresses several, rather than a single, collagenolytic MMPs, and this proteolytic cascade is evidently responsible for the tissue destruction characteristic of adult and juvenile periodontitis.

MMP Inhibition and Downregulation by Bisphosphonates

ABSTRACT: Bisphosphonates are a group of drugs capable of inhibiting bone resorption, and are thus used for the treatment of bone diseases, such as Pagets disease, osteoporosis, and for bone metastases of malignant tumors. Their primary cellular target is considered to be the osteoclast. The molecular mechanisms responsible for the downregulation of bone resorption by bisphosphonates have remain unclear. We have discovered that various matrix metalloproteinases (MMPs) are inhibited in vitro by several bisphosphonates. This novel finding may, in part, explain the efficacy of bisphosphonates in their current indications in humans. In enzyme activity tests using purified and recombinant enzymes, we have observed the inhibition of MMP‐1, ‐2, ‐3, ‐7, ‐8, ‐9, ‐12, ‐13, and ‐14 by clondronate, alendronate, pamidronate, zolendronate, nedrinate, and clodrinate. The IC50s range from 50 to 150 μM. We have also shown that clodronate can downregulate the expression of MT1‐MMP protein and mRNA in several cell lines. Additionally, several bisphosphonates decrease the degree of invasion of malignant melanoma (C8161) and fibrosarcoma (HT1080) cells through artificial basement membrane (Matrigel) in cell cultures at IC50s of 50‐150 μM and below. Having low toxicity and proven to be well tolerated after several years in human use, bisphosphonates have the potential to become one of the main MMP‐inhibitors for MMP‐related human soft and hard tissue‐destructive diseases in the near future.

Expression and induction of collagenases (MMP-8 and -13) in plasma cells associated with bone-destructive lesions

Matrix metalloproteinases (MMPs) collectively degrade extracellular matrix and basement membrane proteins in chronic inflammation and bone‐destructive lesions. This study examined the ability of immunoglobulin‐producing plasma cells, typically present in sites of chronic inflammation, to express collagenases (MMP‐8 and ‐13) in vivo and in vitro. Phorbol‐12‐myristate‐13‐acetate, interleukin‐6, and tumour necrosis factor‐α and heparin with the tumour promoter or cytokines potently enhanced (up to nine‐fold) MMP‐8 and ‐13 expression by the RPMI 8226 myeloma cell line, as evidenced by western blotting and semi‐quantitative reverse transcriptase‐polymerase chain reaction. Immunohistochemical analysis and in situ hybridization revealed that plasma cells expressed MMP‐8 and ‐13 focally in periapical granulomas, odontogenic cysts, and malignant plasmacytomas. MMP‐8 and MMP‐13 from plasma cells can participate in bone organic matrix destruction at sites of chronic inflammation and neoplastic growth. Since MMP‐13 was more frequently expressed than MMP‐8 in plasma cells of strongly recurring keratocysts and malignant plasmacytomas, it is concluded that plasma cell MMP‐13 has a particularly important role in benign and malignant bone‐destructive lesions. Copyright

In vivo collagenase‐2 (MMP‐8) expression by human bronchial epithelial cells and monocytes/macrophages in bronchiectasis

The purpose of this study was to determine whether other cellular sources than neutrophils can express matrix metalloproteinase (MMP)‐8 protein and mRNA in bronchiectatic (BE) lung. The molecular forms of MMP‐8 in the BE bronchoalveolar lavage fluid (BALF) and healthy control BALF were analysed by western immunoblotting. MMP‐8 expression was demonstrated by immunohistochemistry and in situ hybridization in BE lung tissue and by immunohistochemistry in control lung tissue. In the BE BALF, different MMP‐8 species were detected: 70–80 kD MMP‐8 apparently of polymorphonuclear leukocyte (PMN) origin and also 40–60 kD MMP‐8 from non‐PMN cellular sources, such as bronchial epithelial cells, glandular cells or monocytes/macrophages. Both of these MMP‐8 species were elevated and converted to a significant extent to activated forms in BE BALF compared with healthy control BALF. The levels of high molecular weight (>80 kD) MMP‐8 complexes, evidently representing MMP‐8 trapped by endogenous MMP inhibitors and/or MMP‐8 dimers, were significantly elevated in BE BALF compared with healthy control BALF. In BE lung tissue, the MMP‐8 protein and mRNA expression was found in bronchial ciliated epithelial cells, glandular cells, neutrophils, and monocytes/macrophages infiltrating the bronchial epithelial area. Minimal MMP‐8 expression was observed in neutrophils, monocytes/macrophages, and epithelial cells in control lung tissues. In this study, new potential cellular sources have been demonstrated for MMP‐8 in the inflamed lung. MMP‐8 from multiple cellular sources, including inflamed lung epithelium, was activated to a significant extent in the BE BALF, indicating a major role for MMP‐8 in the destruction of lung and bronchial tissues. Copyright

Airway obstruction correlates with collagenase-2 (MMP-8) expression and activation in bronchial asthma.

Matrix metalloproteinases (MMPs) contribute to extracellular matrix and basement membrane degradation in asthma. The present study analyzed molecular forms and degree of activation and expression of MMP-8 in bronchoalveolar lavage fluid (BALF), BALF cells, and bronchial tissue specimens from 14 steroid-naive asthma patients, 13 uncontrolled severe asthma patients, 13 controlled asthma patients, and 14 healthy subjects by Western immunoblotting, immunohistochemistry, and in situ hybridization. Immunohistochemistry and in situ hybridization revealed a prominent MMP-8 immunoreactivity in submucosal inflammatory, glandular, and shed, but not in intact bronchial epithelial cells of asthma patients. In BALF cytospins, both MMP-8 protein and mRNA expression were observed in epithelial cells, macrophages, and polymorphonuclear leukocytes (PMNs). MMP-8 was present in BALFs asthma patients in complex, pro- and active PMN-type, and pro- and active non-PMN–type forms. BALF MMP-8 was significantly converted to active form only in BALFs from steroid-naive and uncontrolled severe asthma patients, but not in BALFs from well-controlled asthma patients or healthy controls. A significant inverse correlation between BALF MMP-8 levels and FEV1 (r = −0.283, p = 0.04), and BALF activated MMP-8 forms and FEV1 (r = −0.427, p = 0.001) was detected. Overall, these data suggest that MMP-8 and its activation has an important role in the airway destruction, healing, remodeling, and treatment response in asthma.

Bisphosphonates inhibit stromelysin-1 (MMP-3), matrix metalloelastase (MMP-12), collagenase-3 (MMP-13) and enamelysin (MMP-20), but not urokinase-type plasminogen activator, and diminish invasion and migration of human malignant and endothelial cell lines.

Bisphosphonates (clodronate, alendronate, pamidronate and zoledronate) at therapeutically attainable non-cytotoxic concentrations inhibited MMP-3, -12, -13 and -20 as well as MMP-1, -2, -8 and -9, but not urokinase-type plasminogen activator (uPA), a serine proteinase and a pro-MMP activator. Dose-dependent inhibition was shown by three independent MMP assays. The inhibition was reduced in the presence of an increased concentration of Ca2+ when compared to physiologic Ca2+ concentration. Alendronate inhibited the in vitro invasion (Matrigel) of human HT1080 fibrosarcoma and C8161 melanoma cells, and the random migration of these malignant and endothelial cell lines capable of expressing MMPs and uPA. The concentration of alendronate required to inhibit 50% of the activity (IC50=40–70 μM) of MMPs corresponded to the IC50 of down-regulation of in vitro invasion and migration. The ability of bisphosphonates to down-regulate the in vitro invasion and random migration was comparable or slighty better in relation to the selective gelatinase inhibitor CTTHWGFTLC peptide. Alendronate but not CTTHWGFTLC peptide promoted the adhesion of HT1080 fibrosarcoma and C8161 melanoma cell lines on fibronectin. Bisphosphonates are broad-spectrum MMP inhibitors and this inhibition involves cation chelation. Bisphosphonates further exert antimetastatic, anti-invasive and cell adhesion-promoting properties, which may prevent metastases not only into hard tissues but also to soft tissues.

Metalloproteinase inhibition reduces lung injury and improves survival after cecal ligation and puncture in rats

BACKGROUND Neutrophil activation with concomitant matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) release has been implicated in the development of sepsis-induced acute lung injury. We hypothesized that COL-3, a chemically modified tetracycline known to inhibit MMP-2 and MMP-9, would reduce lung injury and improve survival in rats following cecal ligation and puncture (CLP). METHODS Sprague-Dawley rats were separated into five groups: 1) sham CLP+ carboxymethylcellulose (CMC; vehicle for COL-3, n = 6); 2) sham CLP + COL-3 (n = 6); 3) CLP + CMC (n = 10); 4) CLP + single-dose (SD) COL-3 administered concomitant with CLP (n = 9); and 5) CLP + multiple-dose (MD) COL-3 administered concomitant with CLP and at 24 h after CLP (n = 15). Rats were sacrificed at 168 h (7 days) or immediately after death, with survival defined as hours after CLP. Histological lung assessment was made based on neutrophil infiltration, alveolar wall thickening, and intraalveolar edema fluid. Lung MMP-2 and MMP-9 levels were assessed by immunohistochemistry. MMP-2 and MMP-9 levels were correlated with survival by simple regression analysis. RESULTS The mortality of rats in the cecal ligation and puncture without treatment group (CLP + CMC) was 70% at 168 h. A single dose of COL-3 in the CLP + COL-3 (SD) group significantly reduced mortality to 54%. Furthermore, with a repeat dose of COL-3 at 24 h after CLP, mortality was significantly reduced to 33%. Pathologic lung changes seen histologically in the CLP + CMC group were significantly reduced by COL-3. A significant reduction in lung tissue levels of MMP-2 and MMP-9 was noted in both groups treated with COL-3. Reduction of MMP-2 and MMP-9 levels correlated with improved survival. CONCLUSION Inhibition of MMP-2 and MMP-9 by COL-3 in a clinically relevant model of sepsis-induced acute lung injury reduces pulmonary injury and improves survival in a dose-dependent fashion. Our results suggest that prophylactic treatment with COL-3 in high-risk patients may reduce the morbidity and mortality associated with sepsis-induced acute respiratory distress syndrome.

Wound Healing in Ovariectomized Rats Effects of Chemically Modified Tetracycline (CMT-8) and Estrogen on Matrix Metalloproteinases -8, -13 and Type I Collagen Expression

Cutaneous wound healing is a complex process involving interactions of various cell types. Skin, in addition to certain other organs, is dependent on estrogen; and estrogen-deficiency is associated with impaired wound healing. Wound healing involves the action of collagenolytic matrix metalloproteinases (MMPs). We investigated the expression and localization of collagenolytic MMPs -8 and -13 by collagenase activity assay, Western immunoblot analysis, in situ hybridization and immunohistochemical staining as well as type I collagen by hydroxyproline content analysis and immunohistochemical staining in cutaneous wounds from aged Sham and ovarioectomized (OVX) rats. After wounding, OVX rats were treated with either placebo, chemically modified tetracycline-8 (CMT-8) or estrogen. We found that MMP-8 and MMP-13 mRNA were expressed in wound epithelium of all samples examined as evidenced by in situ hybridization. Type I collagen, which was abundant in all groups examined, was decreased in OVX rats, but was increased by both CMT-8 and estrogen treatments to the level of Sham group. Hydroxyproline analysis revealed similar results. Western blot data showed that all forms of MMP-8 and MMP-13 were clearly reduced in the CMT-8 treated group compared to OVX. Analysis of collagenolytic activity confirmed the decreased collagenolysis in skin wound extracts from CMT-treated rats when compared with skin wound extracts from OVX rats. Our results show for the first time that MMP-8 mRNA and protein are expressed in rat wound epithelium. We further show that CMT-8 and estrogen have a beneficial effect on skin wound healing in OVX rats by increasing the collagen content and reducing the MMP-mediated collagenolysis.

Gelatinase A (MMP-2), Collagenase-2 (MMP-8), and Laminin-5 γ2-Chain Expression in Murine Inflammatory Bowel Disease (Ulcerative Colitis)

Dextran sulfate sodium-induced inflammatory bowel disease in mice resembles human ulcerative colitis. In inflammatory bowel diseases matrix metalloproteinases contribute to tissue degradation. Laminin-5 is an anchoring filament protein in the basement membrane area that can be cleaved by matrix metalloproteinases. We investigated the expression of matrix metalloproteinases-2 and -8 and laminin-5 γ2-chain in dextran sulfate sodium-induced mice by immunohistochemistry and in situ hybridization. Matrix metalloproteinase-8 expression was evidenced in the colon surface epithelial cells and the protein was more abundant in dextran sulfate sodium-induced mice colon. Matrix metallproteinase-2 and laminin-5 γ2-chain colocalized in the colon surface epithelial cells and in the basement membrane zone as demonstrated by double immunostaining. In dextran sulfate sodium-induced colon, matrix metalloproteinase-2 immunoreactivity was detected in epithelial cells in the lower parts of the crypt and surrounding the degraded crypts. Matrix metalloproteinase-2 and -8 could participate in the local epithelial inflammatory processes and tissue destruction. The presence of laminin-5 γ2-chain indicates alternative anchoring mechanisms in the colon, a compartment devoid of hemidesmosomes.

Soluble membrane‐type 1 matrix metalloproteinase (MT1‐MMP) and gelatinase A (MMP‐2) in induced sputum and bronchoalveolar lavage fluid of human bronchial asthma and bronchiectasis

The aim of this study was to investigate the involvement of the MT1‐MMP/MMP‐2 cascade in induced sputum (IS) and bronchoalveolar lavage fluid (BALF) from bronchial asthma (BA) and bronchiectasis (BE) patients and healthy controls. The molecular forms and cellular origins of MT1‐MMP and MMP‐2 were determined by Western immunoblotting, immunohistochemistry and in situ hybridization. Elevated levels of soluble activated and autocatalyzed MT1‐MMP species as well as activated forms of MMP‐2 in IS and BALF samples from BA and BE patients were evidenced. The activation degrees of soluble MT1‐MMP and MMP‐2 were significantly correlated in BA and BE IS and BALF. Only low levels of both these MMPs were observed in healthy control IS and BALF. The co‐expression of MMP‐2 with MT1‐MMP was evidenced by double immunostaining in bronchial epithelial cells, submucosal glandular cells, smooth muscle cells and monocyte/macrophages. The MT1‐MMP/MMP‐2 cascade is present and active in human inflammatory lung disease fluid and tissue samples. This cascade seemingly reflects the active destructive phases of these chronic lung diseases.