Activated matrix metalloproteinase 8 in serum predicts severity of acute pancreatitis.

OBJECTIVES: Severe acute pancreatitis (SAP) has high morbidity and mortality but there are no widely accepted predictive biomarkers in clinical use. Matrix metalloproteinases (MMPs) are active in tissue destruction and inflammatory responses. We studied whether serum levels of activated MMP-8 (aMMP-8), MMP-9 and their regulators tissue inhibitor of matrix metalloproteinases (TIMP)-1, myeloperoxidase (MPO) and human neutrophil elastase (HNE) could predict the development of SAP. METHODS: The study comprised 214 AP patients (revised Atlanta classification: 142 mild, MAP; 54 moderately severe, MSAP; 18 SAP) referred to Helsinki University Hospital. A venous blood sample was taken within 72 h from the onset of symptoms. Serum levels of aMMP-8 were determined using immunofluorometric assay, and those of MMP-9, TIMP-1, MPO and HNE using enzyme-linked immunosorbent assay. AP groups were compared using Jonckheere-Terpstra test and predictive value for SAP was analyzed using receiver operating characteristics (ROC) analysis. RESULTS: Serum aMMP-8 levels were higher in SAP (median 657 ng/ml, interquartile range 542-738 ng/ml) compared to MSAP (358 ng/ml, 175-564 ng/ml; p < 0.001) and MAP (231 ng/ml, 128-507 ng/ml; p < 0.001). Similar trend was seen with TIMP-1 and MPO. In ROC analysis aMMP-8, MPO and TIMP-1 emerged as potential markers for the development of SAP (areas under ROC curves 0.83, 0.71 and 0.69, respectively). CONCLUSIONS: Serum aMMP-8 measured early in the course of AP (within 72 h of symptom onset) predicted the development of SAP.

Associations of oral fluid MMP-8 with periodontitis in Swiss adult subjects.

OBJECTIVE: MMP-8 is a prominent collagenase in periodontal disease. This cross-sectional study examined whether MMP-8 levels in saliva and gingival crevicular fluid (GCF) are associated with periodontitis in a Swiss population. SUBJECTS AND METHODS: A total of 258 subjects (107 m, 151 f, mean age: 43.5 yr; range: 21-58 yr) acquired from the Swiss bone marrow donor registry participated in the study. Saliva and GCF samples were collected from subjects followed by a thorough dental and periodontal examination. MMP-8 levels were determined with immunofluorometric assay. Associations of MMP-8 levels with periodontal diagnosis, probing pocket depth (PPD) and bleeding on probing were statistically analysed with Pearson chi-square test, Spearman's rho and logistic regression analysis. RESULTS: MMP-8 in GCF correlated with MMP-8 in saliva (p < .001). Periodontitis was more common (p < .001) among subjects with high levels of MMP-8 in saliva and/or GCF compared with subjects with low levels of MMP-8. Higher MMP-8 levels in GCF and saliva were associated with any periodontal diagnosis (mild, moderate or severe), greater PPD, and bleeding on probing (p < .05). When age, gender, smoking, body mass index, number of medications and decayed, missing and filled teeth were adjusted for, all observed associations remained statistically significant. The area under curve of receiver-operating characteristic was 0.67 for saliva and 0.71 for GCF. CONCLUSION: Elevated MMP-8 levels both in saliva and GCF are associated with periodontitis in a normal adult population.

Intestinal alkaline phosphatase at the crossroad of intestinal health and disease - a putative role in type 1 diabetes.

BACKGROUND: Patients with type 1 diabetes have shown an increase in circulating cytokines, altered lipoprotein metabolism and signs of vascular dysfunction in response to high-fat meals. Intestinal alkaline phosphatase (IAP) regulates lipid transport and inflammatory responses in the gastrointestinal tract. We therefore hypothesized that changes in IAP activity could have profound effects on gut metabolic homeostasis in patients with type 1 diabetes. METHODS: Faecal samples of 41 nondiabetic controls and 46 patients with type 1 diabetes were analysed for IAP activity, calprotectin, immunoglobulins and short-chain fatty acids (SCFAs). The impact of oral IAP supplementation on intestinal immunoglobulin levels was evaluated in C57BL/6 mice exposed to high-fat diet for 11 weeks. RESULTS: Patients with type 1 diabetes exhibited signs of intestinal inflammation. Compared to controls, patients with diabetes had higher faecal calprotectin levels, lower faecal IAP activities accompanied by lower propionate and butyrate concentrations. Moreover, the amount of faecal IgA and the level of antibodies binding to oxidized LDL were decreased in patients with type 1 diabetes. In mice, oral IAP supplementation increased intestinal IgA levels markedly. CONCLUSION: Deprivation of protective intestinal factors may increase the risk of inflammation in the gut - a phenomenon that seems to be present already in patients with uncomplicated type 1 diabetes. Low levels of intestinal IgA and antibodies to oxidized lipid epitopes may predispose such patients to inflammation-driven complications such as cardiovascular disease and diabetic nephropathy. Importantly, oral IAP supplementation could have beneficial therapeutic effects on gut metabolic homeostasis, possibly through stimulation of intestinal IgA secretion.

Association between serum and oral matrix metalloproteinase-8 levels and periodontal health status.

BACKGROUND AND OBJECTIVE: Matrix metalloproteinase-8 (MMP-8) is involved in a wide range of pathologies including periodontitis and cardiovascular diseases (CVD). The association between periodontitis and CVD has been repeatedly recognized. The aim of the study was to analyze to what extent circulating active MMP-8 (aMMP-8) is associated with periodontal disease status and oral fluid aMMP-8 levels in otherwise healthy subjects. MATERIAL AND METHODS: In a cross-sectional study, aMMP-8 was measured in serum of 59 volunteers, comprising 19 periodontally healthy subjects, 20 patients with gingivitis as well as 20 with periodontitis. All study subjects were characterized regarding aMMP-8 concentrations in different oral fluids as well as clinically and microbiologically with respect to periodontal disease. aMMP-8 levels in gingival crevicular fluid were measured using the enzyme-linked immunosorbent assay. Saliva enzyme levels as well as circulating aMMP-8 were determined by a time-resolved immunofluorometric assay. Both methods utilized the same monoclonal antibodies. Correlation and regression analyses were performed to study the potential association between serum aMMP-8 and oral parameters. RESULTS: Oral aMMP-8 levels were significantly higher in patients with periodontitis compared to periodontally healthy or gingivitis subjects. Highest serum aMMP-8 concentration was also found in the periodontitis group. The serum levels correlated significantly with oral aMMP-8 as well as with clinical parameters in a dose-dependent manner. These results were confirmed in a multivariate regression analysis. After adjusting for potential confounders, saliva aMMP-8 concentrations as well as periodontitis severity were significant predictors of serum aMMP-8. CONCLUSION: The associations between circulating aMMP-8 and oral aMMP-8 as well as periodontal findings in a dose-dependent manner may contribute to linking periodontal disease with increased CVDsusceptibility.

Infection and apoptosis associated with inflammation in periodontitis: An immunohistologic study.

OBJECTIVE: Evidence of increased apoptosis is observed in periodontitis and may be associated with destruction of the periodontal tissue caused by the increased cell death, with the release of danger signals and subsequent stimulation of the proinflammatory processes. However, the exact mechanisms associated with these processes remain unclear. This study aimed to investigate the presence of the periodontal pathogen Treponema denticola, apoptosis, high mobility group box 1 as a damage-associated molecular pattern, and several inflammatory markers in periodontitis and gingivitis subjects. MATERIALS AND METHODS: Soft tissue specimens from gingival tissues of periodontitis and gingivitis patients were used for immunohistochemical and immunofluorescence staining of T. denticola chymotrypsin-like proteinase (CTLP), apoptosis markers, high mobility group box 1, Toll-like receptor 4, inflammatory cell markers, and proinflammatory cytokines. RESULTS: Treponema denticola was detected in all periodontitis-affected tissues. This was associated with a significant increase in the number of apoptotic cells, including macrophages, alterations in the expression of high mobility group box 1 and its receptor, and increased levels of proinflammatory cytokines compared with gingivitis. CONCLUSIONS: In summary, the presence of T. denticola (especially its CTLP), apoptosis, high mobility group box 1, and inflammatory markers suggests their potential involvement in the pathogenesis of periodontitis.

Cytokine (interleukin-1beta) and MMP levels in gingival crevicular fluid after use of platelet-rich fibrin or connective tissue graft in the treatment of localized gingival recessions.

BACKGROUND AND OBJECTIVE: The objective of this study was to evaluate the levels of MMP-8, MMP-9, TIMP-1 and interleukin-1beta (IL-1ß) in gingival crevicular fluid during the early and late stages of healing in gingival recession sites treated with coronally advanced flap plus platelet-rich fibrin (CAF+PRF) compared with CAF plus connective tissue graft (CAF+CTG). MATERIAL AND METHODS: Twenty-four nonsmoking patients with Miller Class I or Class II localized gingival recession defects in bilateral sites received treatment with either CAF+PRF (PRF group) or CAF+CTG (CTG group). Gingival crevicular fluid samples were collected at baseline and at 10 d and 1 mo, 3 mo and 6 mo after surgery. The levels of MMP-8, MMP-9, TIMP-1 and IL-1ß in gingival crevicular fluid were measured using a time-resolved immunofluorometric assay and ELISAs. RESULTS: Gingival crevicular fluid levels of IL-1ß were significantly elevated in the CTG group at 10 d compared with baseline (p < 0.05). At 10 d after surgery, the levels of TIMP-1 in gingival crevicular fluid showed a significant decrease in the CTG group compared with the PRF group (p < 0.05). The levels of IL-1ß and MMP-8 in gingival crevicular fluid were significantly lower in the PRF group than in the CTG group at 10 d (p < 0.05). No significant differences were found in all clinical and biochemical parameters at 1, 3, and 6 mo between study groups (p > 0.05). CONCLUSION: Root coverage with CAF+PRF has a significant effect on increasing gingival crevicular fluid TIMP-1 levels and suppressing gingival crevicular fluid MMP-8 and IL-ß levels at 10 d. Gingival crevicular fluid levels of MMP-8, MMP-9, TIMP-1 and IL-1ß did not seem to be affected by the technique at later phases of wound healing.

Systemic matrix metalloproteinase-8 and tissue inhibitor of metalloproteinases-1 levels in severe sepsis-associated coagulopathy.

BACKGROUND: Matrix metalloproteinase-8 (MMP-8) and tissue inhibitor of metalloproteinases-1 (TIMP-1) have recently been suggested to be involved in coagulation process. Our objectives were to observe systemic MMP-8 and TIMP-1 levels in patients with severe sepsis with or without disseminated intravascular coagulation (DIC) and to study their relationship with coagulation markers over time. METHODS: Our prospective pilot study included 22 patients with severe sepsis, nine (41%) of whom had overt DIC. We analysed MMP-8 and TIMP-1 serum concentrations by time-resolved immunofluorometric and enzyme-linked immunosorbent assays, respectively, on days 1, 2, 4 and 7 after the intensive care unit admission. Traditional coagulation tests were taken at the same time points. The results were compared between patients with and without DIC. Blood samples from 10 healthy volunteers were used to demonstrate normal levels. RESULTS: Both patient groups had elevated levels of MMP-8 and TIMP-1 as compared with healthy controls. TIMP-1 concentration was almost twofold in DIC patients compared with those without DIC on the first 2 days. MMP-8 was elevated only on day 2. TIMP-1 correlated positively with the severity of coagulation disturbance and with disease severity scores. MMP-8 correlated negatively only with platelet count. CONCLUSION: In this first human study, we could show that TIMP-1 is elevated in the early phase of sepsis-induced overt DIC, and it correlates both with degree of coagulopathy and disease severity. These findings suggest that TIMP-1 may play a role in the pathogenesis of DIC in septic patients.

Effect of azithromycin, as an adjunct to nonsurgical periodontal treatment, on microbiological parameters and gingival crevicular fluid biomarkers in generalized aggressive periodontitis.

UNLABELLED: Emingil G, Han B, Özdemir G, Tervahartiala T, Vural C, Atilla G, Baylas H, Sorsa T. The effect of azithromycin, as an adjunct to nonsurgical periodontal treatment, on microbiological parameters and gingival crevicular fluid biomarkers in generalized aggressive periodontitis. J Periodont Res 2012; 47: 729-739. © 2012 John Wiley & Sons A/S Background and Objective: To study the effectiveness of azithromycin in combination with nonsurgical periodontal therapy on clinical and microbiological parameters, and on the MMP-8 and TIMP-1 levels in gingival crevicular fluid, over a 6-mo time-period in patients with generalized aggressive periodontitis. MATERIAL AND METHODS: Thirty-two patients with generalized aggressive periodontitis were included in this randomized, double-blind, placebo-controlled, parallel-arm study. They were randomly assigned to azithromycin or placebo groups (500 mg once daily for 3 d). Probing depth, clinical attachment levels, presence of bleeding on probing and plaque were recorded. Gingival crevicular fluid samples were obtained from one single-rooted tooth, while microbiological samples were obtained from two single-rooted teeth, all with a probing depth of ≥ 6 mm. Microbiological parameters were analyzed by quantitative real-time PCR for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium nucleatum, Prevotella intermedia and total bacteria. Gingival crevicular fluid biomarkers were determined by immunofluorometric assay and ELISA. RESULTS: All clinical parameters improved, and microbiological parameters and gingival crevicular fluid MMP-8 levels significantly decreased, over the 6-mo period (p < 0.05); both groups demonstrated similar improvements. The azithromycin group presented a higher percentage of deep pockets resolved (probing depth reduction of ≥ 3 mm from baseline) compared with the placebo group at 1 mo (p < 0.05). CONCLUSION: Adjunctive azithromycin therapy provides no additional benefit over nonsurgical periodontal treatment on clinical parameters, microbiological parameters and gingival crevicular fluid biochemical markers investigated in patients with generalized aggressive periodontitis.

Acute myocardial infarction elevates serine protease activity in saliva of patients with periodontitis.

BACKGROUND AND OBJECTIVE: There are indications that acute myocardial infarction (AMI) may have an effect on the oral environment, which is reflected in the expression of salivary and gingival proteinases. According to our knowledge, no studies have been carried out to investigate the effect of AMI on the activities of two major tissue-destructive serine protease and microbial effectors, elastase and cathepsin G, produced by oral fluid polymorphonuclear granulocytes (PMN). Therefore, we compared the activities of elastase and cathepsin G in saliva from patients with AMI and from systemically healthy subjects (non-AMI) with similar periodontal conditions. MATERIAL AND METHODS: A total of 92 patients (47 AMI and 28 non-AMI patients with gingivitis or periodontitis, and 17 systemically and periodontally healthy subjects as a control group) were recruited. Clinical periodontal measurements were recorded, and stimulated whole-saliva samples were collected. The patients with AMI were clinically examined within 3-4 d after admission to the coronary care unit. The activities of saliva neutrophil elastase and cathepsin G were measured after collection, at specific time-points during incubation (from baseline to 23 h) by specific synthetic peptide substrate assays. RESULTS: The saliva of patients with AMI and periodontitis had a significant trend for the highest elastase activities among the study groups. Elastase and cathepsin G activities correlated significantly with each other in the AMI periodontitis group (r = 0.8, p < 0.01). In a logistic regression analysis, the level of salivary elastase activity associated significantly with periodontitis. CONCLUSION: AMI may be reflected in PMN serine protease elastase activity in saliva, despite its strong association with periodontitis.

Reduced expression of lipopolysaccharide-induced CXC chemokine in Porphyromonas gingivalis-induced experimental periodontitis in matrix metalloproteinase-8 null mice.

BACKGROUND AND OBJECTIVE: Matrix metalloproteinase-8 (MMP-8) is a central mediator in chronic periodontitis. Recently developed MMP-8-deficient mice show an impaired polymorphonuclear neutrophil response and more severe alveolar bone loss in Porphyromonas gingivalis-induced experimental periodontitis. The main mediators involved in neutrophil and monocyte/macrophage recruitment and in bone loss include lipopolysaccharide-induced CXC chemokine (LIX/CXCL5), stromal-derived factor-1/CXC chemokine ligand 12 (SDF1/CXCL12) and RANKL. Therefore, the aim of this study was to characterize the expression of LIX/CXCL5, SDF1/CXCL12 and RANKL in Porphyromonas gingivalis-induced experimental periodontitis in MMP-8⁻/⁻ (knockout) and wild-type mice. MATERIAL AND METHODS: MMP-8 null and WT P. gingivalis-infected and uninfected mice were included. Histopathological changes were assessed and LIX/CXCL5, SDF1/CXCL12 and RANKL were immunodetected and quantified. RESULTS: Typical histopathological features of chronic periodontitis were seen in P. gingivalis-infected groups. LIX/CXCL5 expression was restricted to the gingival papilla in all four groups. Significantly lower expression of LIX/CXCL5 was seen in the knockout group compared with the wild-type infected group (p < 0.05). SDF1/CXCL12 and RANKL expression was mainly localized to the alveolar crest, including inflammatory leukocytes, vascular endothelium, osteoblasts and osteoclasts. Significant increases of SDF1/CXCL12 and RANKL were seen in both knockout and wild-type P. gingivalis-infected groups compared with uninfected groups (p < 0.05). CONCLUSION: RANKL and SDF1/CXCL12 are up-regulated in P. gingivalis-induced periodontitis and they appear to be associated with the pathogenesis of the disease. MMP-8 is associated with a reduced expression of LIX/CXCL5 in the P. gingivalis-induced experimental periodontitis model.

Elevated MMP-8 and decreased myeloperoxidase concentrations associate significantly with the risk for peripheral atherosclerosis disease and abdominal aortic aneurysm.

Matrix metalloproteinases are responsible for degradation and remodelling of extracellular matrix and exert important roles in initiation and progression of inflammatory diseases. We aimed to examine the role of Matrix metalloproteinases (MMPs) and their regulators in degenerative arterial diseases. Serum samples were collected from patients with arterial disease (n = 126), who underwent surgery because of symptomatic aorto-occlusive disease (AOD, n = 18), carotid artery stenosis (n = 67) or abdominal arotic aneurysm (n = 41). Serum MMP-1, MMP-8, MMP-13, TIMP-1, myeloperoxidase (MPO) and neutrophil elastase (HNE) concentrations were determined by ELISA, and the molar ratio of MMP-8 and TIMP-1 was calculated. To get reference values, the determinations were done on samples of healthy blood donors (n = 100). In univariate analyses, the patients had higher MMP-8 (P < 0.001), TIMP-1 (P = 0.045), and MMP-8/TIMP-1 (P < 0.001), and lower MPO (P < 0.001) when compared with the blood donors. All three subgroups had higher MMP-8 (P < 0.001) and MMP-8/TIMP-1 (P < 0.001), and lower MPO (P < 0.01, except AOD) levels when compared with the references. In multiple logistic regression analyses, the male gender (P < 0.01), age (P < 0.001), elevated MMP-8 (P < 0.001) and decreased MPO (P < 0.001) concentrations associated significantly with the risk for arterial disease, and provided an area under curve (AUC) of 0.97 in the Receiver operating characteristics analyses. In multiple linear regression analyses, HNE correlated with both MMP-8 (P < 0.001) and MPO (P = 0.008) concentrations. Combination of high MMP-8 and low MPO level in serum eventually reflecting selectively modified neutrophil degranulation may indicate increased risk for arterial disease.

Matrix metalloproteinases-7, -8, -9 and TIMP-1 in the follow-up of diisocyanate-induced asthma.

BACKGROUND: Diisocyanate-induced asthma (DIA) is known to be associated with poor prognosis. We wished to clarify if matrix metalloproteinases (MMP)-7, -8 or -9 or tissue inhibitor of matrix metalloproteinases (TIMP-1) are associated with the functional or inflammatory outcome in DIA patients. METHODS: This is a longitudinal study where 17 patients with DIA diagnosed by a specific challenge test to diisocyanates were monitored. Exposure to diisocyanates was terminated seven (mean) months before the challenge test. The studies included spirometry, histamine challenge test and bronchoscopy. MMP-7, MMP-8, TIMP-1 [Enzyme-linked immunosorbent assay (ELISA)- and immunofluorometric assay-methods], MMP-9 (ELISA and zymography), interferon-gamma, tumour necrosis factor-alpha, interleukin-6, -8, -15, -17, CXCL-5/ENA-78, monocyte chemoattractant protein-1 and macrophage inhibitory factor (MIF) (ELISA) were assayed from bronchoalveolar lavage (BAL) fluid. Inhaled steroid therapy was initiated after the examinations, which were repeated at 6 months and at 3 years during the treatment. The results were compared with those of 15 healthy controls. RESULTS: Inhaled steroid medication increased BAL levels of MMP-9 and MMP-9/TIMP-1 and decreased MMP-7 and MMP-7/TIMP-1. The increase in MMP-9 levels was associated with a decline in the TH-2 type inflammation. CONCLUSIONS: Our data suggest that reduced TH-2 type inflammation in DIA after inhaled steroid medication is reflected as elevated MMP-9 and MMP-9/TIMP-1 levels in BAL. MIF may be the inducer of MMP-9. This might point to some protective role for MMP-9 in DIA.

Effects of inhaled corticosteroids on metalloproteinase-8 and tissue inhibitor of metalloproteinase-1 in the airways of asthmatic children.

BACKGROUND: The effects of corticosteroids on the level and expression of matrix metalloproteinase-8 (MMP-8; collagenase-2) and tissue inhibitors of metalloproteinases (TIMPs) in airway tissue are poorly characterized in vivo. METHODS: We compared MMP-8 and TIMP-1 levels in induced sputum and their expression in airway inflammatory cells of healthy children (n = 27) and of children with newly diagnosed asthma with mild (n = 20) or moderate symptoms (n = 19), before and after 6 months of treatment with inhaled budesonide. RESULTS: At baseline, MMP-8 was higher in asthmatic children with moderate symptoms, TIMP-1 was lower and the MMP-8/TIMP-1 ratio was higher in both groups of asthmatic children compared with controls. Inhaled budesonide increased TIMP-1 levels in both groups of asthmatic children and normalized the MMP-8/TIMP-1 ratio, and this paralleled the improvement in forced expiratory volume in 1 s in children with mild symptoms. At baseline, asthmatic children had significantly more MMP-8-positive macrophages than control children, whereas the number of TIMP-1-positive macrophages was almost the same. Budesonide decreased the percentage of MMP-8-positive macrophages and increased that of TIMP-1-positive macrophages; these changes were significant in asthmatic children with mild symptoms. CONCLUSIONS: Inhaled budesonide normalized the MMP-8/TIMP-1 ratio in asthmatic children by upregulation of TIMP-1 production and downregulation of MMP-8 production by airway macrophages. This change may be a biochemical marker of an effect on airway inflammation and possibly of an ongoing remodeling process that should be further investigated using biopsy specimens.

Longitudinal study of salivary proteinases during pregnancy and postpartum.

BACKGROUND AND OBJECTIVE: Matrix metalloproteinases (MMPs) and their regulators are connected to periodontal inflammation and destruction. However, the presence and role of the salivary MMPs in pregnancy-related gingivitis are not well known. Our longitudinal study aimed to monitor salivary proteinase levels and possible changes, and relate them to periodontal status during pregnancy and postpartum. MATERIAL AND METHODS: Salivary samples were collected from 30 periodontally healthy pregnant women five times (once during each trimester, 4-6 wk after delivery and after lactation) and, as their controls, from 24 non-pregnant women three times (during successive months). Periodontal examination included visible plaque index, bleeding on probing, probing pocket depth and clinical attachment level measurements. Matrix metalloproteinase-8 levels were measured by immunofluorometric assay, and MMP-2 and MMP-9 levels and molecular forms by gelatin zymography. Salivary elastase, myeloperoxidase and tissue inhibitor of matrix metalloproteinase-1 levels were measured by ELISA. RESULTS: Elastase concentrations maintained stable during the follow-up, while myeloperoxidase concentrations increased significantly after delivery. During pregnancy, MMP-8 concentrations were significantly lower than postpartum concentrations, being lowest during the second trimester and highest after delivery, and varying inversely to pregnancy gingivitis, observed as elevated percentages of bleeding on probing and probing pocket depth during the second and third trimester. In pregnant women, the highest MMP-2 and MMP-9 levels were found in saliva after lactation. In the control group, both clinical and enzymological findings remained stable during the follow-up period. CONCLUSION: Our results suggest that hormonal changes during pregnancy induce or enhance susceptibility to gingivitis, while salivary proteinase and myeloperoxidase levels are reduced.

Regulation of Salivary Peptidoglycan Recognition Protein 1 in Adolescents.

INTRODUCTION: Peptidoglycan recognition protein 1 (PGLYRP1), a member of peptidoglycan recognition proteins, is known to be involved in the proinflammatory response toward bacterial infections. Recently, PGLYRP1 was identified as a ligand for triggering receptor expressed on myeloid cells 1 (TREM-1). Although PGLYRP1 is involved in immune and inflammatory responses, its levels in initial stages of periodontal disease in adolescents are currently unknown. OBJECTIVES: We aimed to investigate salivary levels of PGLYRP1 and its correlation with TREM-1, polymorphonuclear leukocyte elastase (PMN elastase), and an active matrix metalloproteinase 8 (aMMP-8) in adolescents. METHODS: Whole saliva samples (n = 537) were collected from 15- to 16-y-old adolescents at Kotka Health Center, Finland, prior to periodontal examination, including measurement of periodontal pocket depth (PPD), visible plaque index (VPI), and bleeding on probing (BOP). Adolescents, clustered as periodontally healthy, gingivitis, or subclinical periodontitis, were tested for salivary levels of TREM-1, PGLYRP1, and PMN elastase by enzyme-linked immunosorbent assay and aMMP-8 by a time-resolved immunofluorometric assay (IFMA). RESULTS: Salivary levels of PGLYRP1 and aMMP-8 were significantly higher in adolescents with subclinical periodontitis and gingivitis compared to individuals with healthy periodontium. TREM-1 and PMN elastase levels were higher in adolescents with subclinical periodontitis compared to healthy individuals but did not reach significance. PGLYRP1 correlated positively with BOP, PPD, VPI, aMMP-8, and TREM-1. CONCLUSIONS: Elevated PGLYRP1 levels in adolescents with gingivitis and subclinical periodontitis and its positive correlation with TREM-1 and aMMP-8 may indicate an association of PGLYRP1 with initial stages of periodontal disease. Sex and poor oral hygiene but not smoking are also associated with higher levels of PGLYRP1. However, PGLYRP1 has a lower discriminating capacity and is therefore a less reliable marker alone in the diagnosis of initial stages of periodontal disease in adolescents. KNOWLEDGE TRANSFER STATEMENT: PGLYRP1, a member of peptidoglycan recognition proteins, is a ligand for TREM-1. Elevated PGLYRP1 levels in adolescents with gingivitis and subclinical periodontitis and its positive correlation with TREM-1 and aMMP-8 may indicate an association of PGLYRP1 with initial stages of periodontal disease. However, it has a lower discriminating capacity and is therefore a less reliable marker alone in the diagnosis of periodontal disease in adolescents.

Gingival tissue and crevicular fluid co-operation in adult periodontitis.

Activated matrix metalloproteinase-3 (MMP-3) can contribute to periodontal ligament destruction in adult periodontitis. Since MMP-3 has been reported to activate proMMP-8 and -9, it was speculated that gingival tissue fibroblast-derived MMP-3 might, in periodontitis, be responsible for activation of gingival crevicular fluid (GCF) neutrophil-derived proMMP-8 and -9. Immunohistochemistry disclosed MMP-3 in gingival fibroblasts in periodontitis. Cultured gingival fibroblasts released only pro-MMP-3 when stimulated with tumor necrosis factor-alpha. However, Western blot revealed partially activated MMP-3, MMP-8, and MMP-9 in periodontitis GCF. Active MMP-8 (p < 0.05) and MMP-9 (p < 0.05) correlated with the presence of active MMP-3. It seems that resident gingival fibroblasts produce pro-MMP-3 in GCF, where it becomes activated, probably by cathepsin G or elastase released by neutrophils. Active MMP-3 then activates neutrophil-derived pro-MMP-8 and -9. Different tissue compartments/cells exert co-operative actions in mutual local MMP activation cascades.

Painful tooth stimulation elevates matrix metalloproteinase-8 levels locally in human gingival crevicular fluid.

Recent studies have demonstrated that pulpal pain can induce neurogenic inflammatory reactions in gingiva and the expression of pro-inflammatory neuropeptides in gingival crevicular fluid (GCF). Neuropeptides co-ordinate the activity of immuno-effector cells and may influence the secretion of matrix metalloproteinase (MMP)-8, the major tissue-destructive protease in GCF. With this background, we studied whether experimental pulpal pain can trigger changes in GCF MMP-8 levels. The molecular forms of MMP-8 in the GCF of stimulated and non-stimulated teeth were analyzed by Western immunoblot, and MMP-8 levels by quantitative immunofluorometric assay. Painful stimulation of the upper incisor provoked significant elevations in GCF MMP-8 levels of the stimulated tooth. Western immunoblot revealed elevations in both neutrophil- and mesenchymal-type MMP-8 isoforms. At the same time, the GCF MMP-8 levels of the non-stimulated teeth were not changed. Analysis of these data indicated that pulpal pain can induce local elevations in MMP-8 levels in GCF.

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.

Tumor necrosis factor-alpha and its receptors, p55 and p75, in gingiva of adult periodontitis.

Tumor necrosis factor-alpha (TNF-alpha), a pro-inflammatory cytokine, can stimulate matrix metalloproteinase synthesis and osteoclastic bone resorption. We hypothesized that elevated expression of TNF-alpha and its p55 and p75 receptors (TNF-R) in gingival tissue might associate with periodontitis. Immunohistochemistry was used for the study of the localization of TNF-alpha and its p55 and p75 TNF-R in adult periodontitis (AP) gingival tissue, in comparison with that in healthy control specimens. TNF-alpha and p55 TNF-R were detected in sulcular epithelial basal cells and in monocyte/macrophages, fibroblasts, and endothelial cells in the AP gingival tissue specimens, but mainly in fibroblasts and endothelial cells in control specimens. P75 TNF-R was occasionally found in monocyte/macrophage-like cells in gingival tissue specimens. The percentage of TNF-alpha-containing cells was not increased in AP compared with controls (13.2%+/-6.1% vs. 12.8%+/-7.6%), but, due to the increased cellularity of AP samples, the number of TNF-alpha positive cells/mm2 was clearly increased (1621+/-663 vs. 664+/-191, p > 0.001). Thus, AP gingival tissue has an elevated expression of TNF-alpha and especially its p55 receptor, suggesting that TNF-alpha may contribute to tissue degradation in periodontitis.

Fatigue and health profile in sicca syndrome of Sjögren's and non-Sjögren's syndrome origin.

OBJECTIVE: To assess the health status and fatigue in sicca patients with or without Sjögren's syndrome (SS) and to test whether the immune-inflammatory activity or the extent of the disease predict fatigue in SS. METHODS: The Medical Outcomes Study Short-Form General Health Survey (MOS SF-36) was used in 1 degree SS (n = 90), 2 degrees SS (n = 24), non-SS patients with sicca symptoms (n = 15) and healthy population controls (n = 126). Laboratory values and clinical findings were used to predict fatigue in SS. RESULTS: 74% of the SS and 80% of the non-SS sicca patients felt themselves tired. Vitality score values were 40.2 +/- 20.3 in 1 degree SS, 42.1 +/- 20.6 in 2 degrees SS and 29.0 +/- 15.8 in non-SS. The health profiles were similar in 1 degree and 2 degrees SS, worse (p < 0.001) than in normal controls, but in most aspects better than in non-SS sicca patients. In SS neither hemoglobin, ESR nor CRP predicted fatigue. Surprisingly, high serum IgG (p < 0.05), antinuclear antibodies (ANA) (p < 0.01) and SS-A antibodies (p < 0.05) values correlated positively with vitality. The number of disease manifestations correlated negatively with vitality (p < 0.004). The total number of disease manifestations, and ANA and/or SS-A autoantibodies were the best predictors of fatigue, but explained it only to 17-57%. CONCLUSION: Patients with fatigue and perceived ill health but without fibromyalgia had sicca symptoms and low basal tear and salivary secretion rates, indicating that cortical events can lead to a SS-like sicca syndrome. Even in SS fatigue is only in part explained by clinical disease manifestations and laboratory tests assessing inflammation and autoimmunity. Fatigue in both SS and non-SS sicca syndrome more likely correlates to other features, such as neuroendocrine aspects of the disease.