Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0031099 (periodontitis)
 12,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate the effects of a combination of an antibacterial agent (ofloxacin) and a collagenase inhibitor (FN-439) in the root canal treatment of apical periodontitis, we studied the healing process of experimentally induced periapical lesions in rats by using immunohistochemical methods. With a topical application of a combination of ofloxacin and FN-439 following experimentally induced periapical lesions, both neutrophils and macrophages became significantly decreased in number, while active cementogenesis and extensive bone formation were seen in the periapical region. However, the use of ofloxacin alone also demonstrated a beneficial effect on periapical inflammation and healing. Therefore, it is suggested that ofloxacin is powerful against bacterial infection whether FN-439 is added. The only observed effect of a combination of ofloxacin and FN-439 is that it may more effectively inhibit osteoclastic bone resorption and activate the remodeling of the apical periodontal tissue if this combined medicament is used in a stage of active bone destruction characterized by high production of tissue collagenase.
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PMID:Effects of a combination of an antibacterial agent (ofloxacin) and a collagenase inhibitor (FN-439) on the healing of rat periapical lesions. 922 Jul 52

The exact molecular mechanisms of the loosening of a dental implant are not well-known. The characteristics of implant sulci are similar to those of periodontal sulci regarding gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF). Proteolytic enzymes, matrix metalloproteinases (MMPs), participate in peri-implant tissue remodeling. Clodronate is a well-tolerated bisphosphonate-group drug currently used in bone-resorption-related diseases in humans. The mechanisms of bisphosphonate action are not clarified. Collagenase activity in diseased PISF was significantly higher than in the clinically healthy group. Immunoblotting disclosed that diseased PISF contained increased immunoreactives MMP-8 compared with the healthy PISF. The residual latent collagenase activity in the diseased PISF was activated by gold thioglucose and inhibited completely by 100 microM of doxycycline closely resembling pure neutrophil collagenase (MMP-8). The presence of MMP-8 in diseased but not in clinically healthy PISF may prove to be a useful biochemical indicator to monitor peri-implant health and disease. Pure human neutrophil collagenase (MMP-8) and the MMP-8 present in PISF and in the GCF of both loosening implants and periodontitis-affected teeth were efficiently inhibited in vitro by clodronate (50% inhibition [IC50] was achieved by 150 microM of clodronate), an osteoactive, antiresorptive bisphosphonate. Furthermore, the new finding suggests an extended and hitherto-undescribed potential for clodronate in preventing the loosening of both implants and teeth, based on a dual beneficial effect: prevention of both bone resorption/osteolysis and of soft tissue/dental ligament destruction. Potential new therapeutic indications based on the collagenase-inhibiting effect of clodronate provide potential new therapeutic indications for a variety of diseased involving connective tissue breakdown, such as periodontal disease, arthritides, and tumor invasion.
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PMID:Human neutrophil collagenase MMP-8 in peri-implant sulcus fluid and its inhibition by clodronate. 929 86

A reasonable interpretation of the present evidence indicates that diabetes, when a complication of periodontitis, acts as a modifying and aggravating factor in the severity of periodontal infection. Diabetics with periodontitis who were young and poorly controlled, those who were long-duration diabetics, especially those over 30 years old, demonstrated more attachment loss, bone loss, and deeper probing pocket depths than their nondiabetic controls. It seems that the earlier the onset of diabetes and the longer the duration, especially without consistent control, the more susceptible the individual will be to periodontal disease. Consequently, once a diabetic contracts periodontal disease, it is usually more destructive. Although plaque scores of diabetics may be comparable to or even less than those of nondiabetics, diabetics often exhibit higher gingival index scores. The elevation of this particular clinical parameter is indicative of the microangiopathy associated with diabetes. Diabetic microangiopathy contributes to compromised delivery of nutrients to surrounding tissues and poor elimination of metabolic waste products. The complications associated with diabetes such as macroangiopathy, microangiopathy (i.e., retinopathy), ketoacidosis, and hyperglycemia result in impaired wound healing, immunosuppression, and susceptibility to bacterial infection. Individuals ages 30 to 40 suffering from diabetic retinopathy had significantly more gingival inflammation than controls or diabetics without complications. Collagen metabolism is defective in diabetics and is one component underlying delayed wound healing. Animal studies have been instrumental in elucidating the details of delayed wound healing. Hyperglycemia was associated with increased collagenase and protease activity in the gingiva of rats. Vascular wound healing in rats, particularly new re-endothelialization across vascular anastomoses, was significantly impaired. Diabetic abnormalities in immune response include impaired neutrophil chemotaxis, phagocytosis, and adhesion. Decreased neutrophilic chemotactic response seems to be attributable to protein factors in diabetic serum that competitively bind neutrophil receptors, thereby preventing complement-mediated phagocytosis. Because diabetics are not able to eliminate circulating immune complexes (CIC) effectively, serum CIC levels are elevated. There are microbiological differences in the characteristic flora of NIDDM patients and IDDM patients with periodontitis. These differences are not associated with diabetic impaired immune response. Ultimately, bacterial plaque is the primary etiology of periodontal diseases. Evidently, the host's response to bacterial plaque and ability to heal following surgery is altered by diabetic disease. Therefore, a thorough history regarding onset of diabetes, duration, and diabetic control would prove useful in the clinical management of diabetics presenting for treatment of periodontal disease.
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PMID:Periodontal disease, diabetes, and immune response: a review of current concepts. 947 64

The pathogenesis of tobacco-related periodontal diseases is not well understood. The purpose of this study was therefore to investigate smokeless tobacco extract (ST) and nicotine effects on prostaglandin E2 (PGE2) and interleukin-1beta (IL-1beta) secretion by peripheral blood mononuclear cells (PBMC, consisting of monocytes and lymphocytes) and gingival mononuclear cells (GMC). Both peripheral blood and gingival tissue adjacent to the alveolar crest were taken from non-smoking adult periodontitis patients. Gingival tissue was treated with collagenase and deoxyribonuclease and GMC and PBMC were isolated by Ficoll-Hypaque centrifugation. GMC and PBMC (100,000 cells/200 microl) were cultured for 24 hours in supplemented RPMI 1640 alone (control), or in supplemented RPMI 1640 containing 1% ST, 100 microg/ml nicotine, 1 microg/ml Porphyromonas gingivalis LPS, or 1 microg/ml P. gingivalis LPS and either 100 microg/ml nicotine or 1% ST. Enzyme immunoassays were used to quantify PGE2 and IL-1beta. Treatments were compared by repeated measures ANOVA. 100 microg/ml nicotine (7-fold, p<0.02) and 1% ST (3.5-fold, p<0.004) significantly increased secretion of PGE2 by PBMC relative to control cultures. 100 microg/ml nicotine and 1% ST, however, had no effect on IL-1beta secretion by PBMC. Enhanced PGE2 secretion also was seen when PBMC were treated with P. gingivalis LPS+ 100 microg/ml nicotine relative to P. gingivalis LPS alone (p<0.007). In contrast, 100 microg/ml nicotine significantly downregulated IL-1beta secretion by GMC relative to medium alone (p<0.008) and had no effect on PGE2 secretion by GMC. These data indicate that while nicotine and ST can stimulate PBMC to secrete PGE2, they cannot activate further mononuclear cells extracted from gingiva, possibly due to maximal previous stimulation in the periodontitis lesion.
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PMID:Nicotine and smokeless tobacco effects on gingival and peripheral blood mononuclear cells. 954 95

Increased proliferation of mucosal epithelium during inflammation is associated with degradation of subepithelial connective tissue matrix and local invasion of the epithelial cells. Here we have studied, whether collagenase-3 (MMP-13), a collagenolytic matrix metalloproteinase with an exceptionally wide substrate specificity, is expressed in the epithelium of chronically inflamed mucosa. Examination of human gingival tissue sections from subjects with chronic adult periodontitis with in situ hybridization revealed marked expression of MMP-13 in basal cells of some epithelial rete ridges expanding into connective tissue. Immunohistochemical staining demonstrated that these cells also expressed strongly laminin-5, suggesting that they are actively migrating cells. A strong signal for MMP-13 mRNA was occasionally also noted in the suprabasal epithelial cells facing the gingival pocket, whereas no collagenase-1 (MMP-1) mRNA was detected in any areas of the epithelium. MMP-13 expression was also detected in fibroblast-like cells associated with collagen fibers of the inflamed subepithelial connective tissue. In organ culture of human oral mucosa, MMP-13 mRNA expression was observed in epithelial cells growing into connective tissue of the specimens. Regulation of MMP-13 expression was examined in cultured normal nonkeratinizing epithelial cells isolated from porcine periodontal ligament. In these cells, MMP-13 expression at the mRNA and protein level was potently enhanced (up to sixfold) by tumor necrosis factor-alpha, transforming growth factor-beta(1), and transforming growth factor-alpha and by keratinocyte growth factor in the presence of heparin. In addition, plating periodontal ligament epithelial cells on type I collagen stimulated MMP-13 expression (sevenfold) as compared with cells grown on tissue culture plastic. The results of this study show, that expression of MMP-13 is specifically induced in undifferentiated epithelial cells during chronic inflammation due to exposure to cytokines and collagen. Thus, it is likely that MMP-13 expression is instrumental in the subepithelial collagenolysis and local invasion of the activated mucosal epithelium into the connective tissue.
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PMID:Collagenase-3 (matrix metalloproteinase-13) expression is induced in oral mucosal epithelium during chronic inflammation. 962 53

Here, we describe the influence of heparin(s) on the interleukin-1-beta (IL-1beta)-induced expression of collagenase (matrix metalloproteinase-1, MMP-1), stromelysin-1 (matrix metalloproteinase-3, MMP-3) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in human gingival fibroblasts (HGF). Amounts of secreted enzymes and inhibitors as well as their mRNA steady-state levels increased significantly following supplementation of HGF culture medium with 2 ng/mL of IL-1 beta1. Addition of heparin to cell culture medium 1 hour following IL-1beta decreased MMP and TIMP-1 expression in a dose-dependent manner. The inhibitory effect of heparin was significant at a concentration as low as 1 microg/mL. These findings could be reproduced with a low Mr heparin fragment devoid of anticoagulant activity. Heparin and fragments might therefore reduce the excessive proteolytic capacity of the gingival fibroblast during inflammation and could be useful as pharmacological agent(s) in gingivitis and periodontitis.
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PMID:Influence of heparin(s) on the interleukin-1-beta-induced expression of collagenase, stromelysin-1, and tissue inhibitor of metalloproteinase-1 in human gingival fibroblasts. 982 76

Periodontitis is characterized by advancement of a narrow band of epithelium (1-10 cells wide) through the collagenous periodontal ligament in response to bacterial accumulation and infection. A modulating role by epithelial cells in the progression of periodontitis was hypothesized due to the close proximity of the advancing epithelium to both the etiological bacteria and to the collagen fibers of the ligament. We demonstrate that rat mucosal epithelial cells and human fibroblasts are similarly stimulated to degrade a collagen type I cellular substrate by thiol-dependent activity released by the major periodontal pathogen Porphyromonas gingivalis. A purified, extracellular bacterial thiol-proteinase from P. gingivalis ATCC 33277 stimulated mucosal epithelial cells to upregulate expression of collagenase and stromelysin, and to degrade a collagen type I fibril matrix. Stimulation of the epithelial cells with this purified proteinase was associated with morphological changes in the cells and with accumulation of secreted latent procollagenase throughout the culture medium. Release of active collagenase was minimal and collagen degradation by the epithelial cells was discreet and localized subcellularly suggesting the possibility that activation of secreted procollagenase was cell-associated. We conclude that a collagen-degrading phenotype can be stimulated in relatively quiescent mucosal epithelial cells and fibroblasts by the presence of bacterial proteinase. These experiments suggest roles for the P. gingivalis thiol-proteinase and the epithelial cell in the pathogenesis of periodontal disease and demonstrate the potential for dysregulation of extracellular matrix remodeling events during healing of other bacterially infected wounds.
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PMID:Induction of matrix metalloproteinases and a collagen-degrading phenotype in fibroblasts and epithelial cells by secreted Porphyromonas gingivalis proteinase. 984 6

A seminal experiment involving a germ-free rat model of connective tissue breakdown (followed soon thereafter by a series of in vitro studies) identified an unexpected non-antimicrobial property of tetracyclines (TCs). This ability of TCs to inhibit matrix metalloproteinases (MMPs) such as collagenase was found to reflect multiple direct and indirect mechanisms of action, and to be therapeutically useful in a variety of dental (e.g., adult periodontitis) and medical (e.g., arthritis, osteoporosis, cancer) diseases. The site on the TC molecule responsible for its MMP-inhibitory activity was identified which led to the development of a series of chemically modified non-antimicrobial analogs, called CMTs, which also have therapeutic potential but do not appear to induce antibiotic side-effects. Longitudinal double-blind studies on humans with adult periodontitis have demonstrated that a sub-antimicrobial dose of doxycycline (previously reported to suppress collagenase activity in the periodontal pocket) is safe and effective and has recently been approved by the FDA as an adjunct to scaling and root planing.
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PMID:Tetracyclines inhibit connective tissue breakdown by multiple non-antimicrobial mechanisms. 997 17

Previous trials had indicated that various schedules of sub-antimicrobial doxycycline significantly reduced gingival crevicular fluid (GCF) collagenase activity in adult patients with periodontitis with no evidence of emergent tetracycline-resistant (Tcr) marker oral flora. The purpose of this nine-month study was to expand these observations, emphasizing newer microbial diagnostic methods. Subgingival paper point samples were obtained at baseline (BL), 3, 6, and 9 months. Four subject treatment groups in a double-blind design were evaluated by mechanical scaling and root planing (SRP) and/or 20 mg doxycycline BID (Periostat). Thirty-eight patients entered the study at baseline (BL). Dark-field microscopy on 260 samples showed that morphotype distribution was independent of treatment schedule. Culture analysis of the 3 most prevalent isolates recovered showed that Streptococcus and Prevotella species accounted for approximately 85% of the 724 cultures. There did not appear to be any overgrowth or replacement by opportunistic oral flora. Of 658 susceptibility patterns evaluated by Etest, the MIC50/90 and mode MIC showed stable patterns, independent of treatment group. Our findings were different from those of previously published reports, but may be partly explained by the lack of universally standardized methods in oral microbiology and interpretive criteria for susceptibility testing.
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PMID:Long-term sub-antimicrobial doxycycline (Periostat) as adjunctive management in adult periodontitis: effects on subgingival bacterial population dynamics. 997 19

The anti-resorptive properties of tetracyclines (TCs) and their non-antimicrobial, chemically modified analogues (CMTs) have enormous therapeutic potential in medicine and dentistry. Osseous destructive diseases associated with excessive mammalian collagenase (matrix metalloproteinase) activity and collagen breakdown include malignancy, arthritis, and periodontitis. However, apart from the significant antimatrix metalloproteinase effects of TCs, TCs/CMTs are also potent inhibitors of osteoclast function (i.e., anti-resorptive). Thus, TCs can affect several parameters of osteoclast function and consequently inhibit bone resorption by (1) altering intracellular calcium concentration and interacting with the putative calcium receptor; (2) decreasing ruffled border area; (3) diminishing acid production; (4) diminishing the secretion of lysosomal cysteine proteinases (cathepsins); (5) inducing cell retraction by affecting podosomes; (6) inhibiting osteoclast gelatinase activity; (7) selectively inhibiting osteoclast ontogeny or development; and (8) inducing apoptosis or programmed cell death of osteoclasts. TCs/CMTs, as anti-resorptive drugs, may act similarly to bisphosphonates and primarily affect osteoclast function.
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PMID:Effects of tetracyclines on bone metabolism. 997 23


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