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Objective: The aim was to profile serum and salivary levels of active-matrix metalloproteinase (aMMP)-8, tissue inhibitor MMP (TIMP)-1, aMMP-8/TIMP-1 ratio, total MMP (tMMP)-9, tMMP-9/TIMP-1 ratio, myeloperoxidase (MPO), and human neutrophil elastase (HNE) in periodontitis and rheumatoid arthritis (RA)., Materials and Methods: Rheumatoid arthritis patients with periodontitis (RA + P, n = 26), periodontally healthy RA patients (RA, n = 23), systemically healthy periodontitis patients (P, n = 24), and controls (C, n = 24) were included. aMMP-8 levels were determined by a time-resolved immunofluorescence assay (IFMA), TIMP-1, tMMP-9, MPO, and HNE levels were measured by enzyme-linked immunosorbent (ELISA) assays., Results: Higher salivary aMMP-8 (p < 0.001), aMMP-8/TIMP-1 ratio (p = 0.043), tMMP-9 (p = 0.011), tMMP-9/TIMP-1 ratio (p = 0.022), MPO (p = 0.026) and HNE (p < 0.001) levels were detected in P relative to the controls. Salivary TIMP-1 was increased in RA patients regardless of periodontal status (RA + P vs. P: p = 0.038; RA vs. C: p = 0.020). Serum neutrophil proteases were increased in RA groups (RA + P, RA) compared to systemically healthy groups (P, C) (p < 0.05)., Conclusions: Serum levels of neutrophil proteases were increased in RA study groups; however rheumatologic status seemingly does not affect salivary levels of these proteins., (© 2023 The Authors. Oral Diseases published by Wiley Periodicals LLC.)

Objectives: Matrix metalloproteinases are enzymes that participate in numerous inflammatory responses and have been targeted as biomarkers in numerous pathologic states. The detection of active matrix metalloproteinase-8 (aMMP-8) using a mouthrinse point-of-care test (POCT) has emerged as a diagnostic marker for periodontitis and other systemic inflammatory states. The objective of this pilot study was to assess the applicability of aMMP-8 POCT in an oral and maxillofacial surgery clinic and to evaluate the relationship between aMMP-8 levels and different patient groups., Materials and Methods: aMMP-8 POCT samples were collected from patients in an oral and maxillofacial surgery clinic during a one-month period. aMMP-8 levels were analyzed using a chairside lateral-flow immunotest and a digital reader. Clinically relevant patient variables were collected and descriptively evaluated. aMMP-8 levels over 20 ng/ml were considered to be elevated., Results: A total of 115 patients were interviewed of which 112 agreed to the test (97.4%). Elevated aMMP-8 levels were observed in 58 (51.8%) patients. Bone loss was noted in 75 (67.0%) patients. Of these patients, aMMP-8 levels were elevated in 47 (62.7%) patients. Patients at an increased risk of infection had 35.5% higher aMMP-8 values on average compared to patients with no prior illnesses., Conclusion: aMMP-8 POCT provides a non-invasive and reliable method for measuring aMMP-8 levels. Future studies are warranted to assess the clinical relevance between elevated aMMP-8 levels and specific patient groups., Clinical Relevance: The rapid availability of the test score allows an immediate impact on treatment planning., (© 2023. The Author(s).)

Objectives: The aim of this study is to examine correlations between different oral rinse matrix metalloproteinase (MMP)-8 protein species in western blot (WB) analysis, quantitative MMP-8 measurements, and patient-related factors. Elevated activated MMP-8 (aMMP-8) associate with periodontitis and a diagnostic point-of-care technology has been developed based on aMMP-8. In WB, different MMP-8 protein species can be analyzed. Relative abundancy of fragmented 20-25 kDa forms in WB has been associated with and reflects MMP-8 activation and related fragmentation and elevated quantitative aMMP-8 measurements., Material and Methods: A random sample of 192 participants from a periodontal disease screening study was used for this study. Oral rinse samples for biomarker analyses were collected before clinical periodontal examinations. aMMP-8 immunofluorometric (IFMA) and WB analysis (utilizing the same monoclonal antibody, 8708), polymorphonuclear leukocyte (PMN) elastase activity test and tissue inhibitor of metalloproteinases (TIMP)-1 ELISA levels were performed from the oral rinse samples. Distinct MMP-8 protein species were differentiated in the WB analysis. Principal component (PC) analysis was conducted to explore correlation patterns between the different species. Adjusted correlation analysis between the extracted PCs of WB and aMMP-8 IFMA levels and multilevel regression analysis were conducted to explore if the other periodontal disease-related biomarkers and clinical surrogate measures and patient-related factors are co-variating with the extracted components., Results: Distinct correlation patterns between the MMP-8 protein species were observed. The first four PCs explained 89% of the whole variance in PC analysis. Statistically significant correlation (p < 0.05) were observed as follows: PC1 positively with 21 kDa (r = .69) and 25 kDa fragments (r = .55) and negatively with 150 kDa complexes (r = -.46). PC2 correlated with 45 (r = .70) and 55 kDa (r = .65) activated forms, PC3 with 70-80 kDa latent proforms (r = .63) and 90-100 kDa complexes (r = .67), and PC4 with 35 kDa fragments (r = .81). There were significant correlations between quantitative (IFMA) aMMP-8 measurements and PC1 (p < 0.001), PC2 (<0.05) and PC3 (<0.05) but not with PC4. In multilevel regression models age, PMN elastase activity, TIMP-1 levels, and a number of 4-5 mm periodontal pockets were associated with PC1, nonsmoking with PC2, age and PMN elastase activity with PC3, and age and smoking with PC4., Conclusions: Relative abundancy of fragmented 21-25 kDa protein species was correlated with the quantitative aMMP-8 (IFMA) measurements, which is in line with previous results. Different patient-related factors (smoking, age, proteolytic activity) may modify the formation of different MMP-8 protein species in oral rinse samples and may cause variability in quantitative aMMP-8 measurement., (© 2023 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Objective: To analyse the correspondence between aMMP-8 PoC test results and the clinical endpoints of non-surgical periodontal treatment in stage III/IV periodontitis., Background: The diagnostic success of the active-matrix metalloproteinase-8 (aMMP-8) point-of-care (PoC) test has been demonstrated in various studies, but the evidence of its accuracy following periodontal treatment is limited., Materials and Methods: Altogether 42 stage III/IV grade C periodontitis patients were included in this prospective diagnostic study. Clinical periodontal indices were recorded, aMMP-8 PoC test was applied and mouthrinse was collected before and at 6, 12 and 24 weeks after non-surgical periodontal treatment. Quantitative aMMP-8 levels were determined with immunofluorometric assay (IFMA) for the verification of the PoC test results. The accuracy of the aMMP-8 PoC test was assessed using previously established clinical endpoints as references., Results: Sensitivity and specificity of aMMP-8 PoC test to indicate clinical endpoints were ranged as follows: Sensitivity 71.4% at baseline, 39.3%-42.4% at week 6, 28.6%-32.4% at week 12 and 35.3%-42.9% at week 24; specificity 64.3%-80% at week 6, 40%-57.1% at week 12 and 56%-64.3% at week 24., Conclusions: The accuracy of aMMP-8 PoC test in identifying clinical endpoints after non-surgical periodontal treatment is reduced in relation to baseline. Individual healing patterns of each diseased pocket eventually limit the accuracy of the dichotomous aMMP-8 oral rinse test during the post-treatment period., (© 2023 The Authors. Journal of Periodontal Research published by John Wiley & Sons Ltd.)

Objectives: This case control study examined the associations of HLA antigens and periodontitis with the salivary level of active MMP-8 (aMMP-8)., Materials and Methods: A total of 202 subjects, registered as Swiss bone marrow donors, participated in the study. HLA-A, -B, and -C types were determined by serology or PCR. Saliva samples were collected from subjects, followed by a periodontal examination. The salivary level of aMMP-8 was determined with immunofluorometric assay., Results: The mean salivary level of aMMP-8 was directly comparable to the grade of periodontitis and increased from healthy to mild/moderate to severe (125.0 ± 132.1, 200.6 ± 170.2, 290.1 ± 202.3 ng/ml; p < 0.001 between each group, respectively). The only association between the HLA types and the salivary level of aMMP-8 was observed in subjects with HLA-A11. Subjects with healthy periodontium and HLA-A11 had a lower level of aMMP-8 (49.2 ± 32.5 ng/ml) compared with subjects without HLA-A11 (123.6 ± 119.2; p = 0.048). Among subjects with periodontitis, a higher level of aMMP-8 (394.2 ± 255.6 ng/ml) was observed in subjects with HLA-A11 compared with subjects without HLA-A11 (201.1 ± 146.1 ng/ml; p < 0.002). This finding was statistically significant also after adjusting for sex, age, smoking, tooth brushing and the number of medications (p < 0.05)., Conclusions: HLA-A11 is associated with the salivary level of aMMP-8 which contributes to the subject's immune and inflammatory response in periodontium., (© 2021 The Authors. Clinical and Experimental Dental Research published by John Wiley & Sons Ltd.)

Background and Aims: Chymotrypsin-like-proteinase of Treponema denticola (Td-CTLP) can stimulate the protein expression and activation of matrix metalloproteinase (MMP)-8 (or collagenase-2), a potent tissue destructive enzyme from gingival cells in vitro. The aims of this study were 1) to demonstrate the proMMP-8 (or latent MMP-8) activation by Td-CTLP in vitro and 2) to detect Td-CTLP and MMP-8 protein levels in the tissue samples of peri-implantitis and periodontitis patients., Materials and Methods: proMMP-8 activation by Td-CTLP was analyzed by immunoblots. Tissue specimens were collected from 38 systemically healthy and non-smoking patients; 14 of whom had moderate to severe periodontitis, 10 of whom were suffering from peri-implantitis, and finally 14 of whom showed no sign of periodontal inflammation nor radiological bone decay (control group). The immune-expression levels of MMP-8 and Td-CTLP in the epithelium and the connective tissue were analyzed immunohistochemically. A pixel color-intensity analyze was performed with ImageJ software (version 1.46c; Rasband WS, National Institutes of Health, Bethesda, MD, USA) to obtain a comparable numeral score for each patient's epithelium and connective tissue MMP-8 and Td-CTLP enzyme level., Results: Td-CTLP activated proMMP-8 in vitro by converting the 70-75 kDa proMMP-8 to 65 kDa active MMP-8. Also, lower molecular size 25-50 kDa parts of MMP-8 were formed. There was no statistically significant difference between the study groups in terms of their MMP-8 and Td-CTLP levels in the epithelium or in the connective tissue., Conclusion: Regarding the limits of this study, it can thus be said that the Td-CTLP enzyme can activate the host proMMP-8 enzyme. Tissue protein levels of MMP-8 and Td-CTLP do not seem to be changed in peri-implantitis and in periodontitis., (Copyright © 2021 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Matrix metalloproteinase-8 (MMP-8) and tissue inhibitor of metalloproteinases-1 (TIMP-1) have been shown to predict prognosis in sepsis. However, MMP-8 and TIMP-1 in Staphylococcus aureus bacteremia (SAB) lacks evaluation and their role in the pathogenesis of SAB is unclear., Methods: MMP-8 and TIMP-1 and MMP-8/TIMP-1 molar ratio were determined at days 3, 5 and 28 from positive blood cultures in patients with methicillin-sensitive SAB and the connection to disease severity and early mortality was determined., Results: Altogether 395 SAB patients were included. Patients with severe sepsis or infection focus presented higher MMP-8 levels at day 3 and 5 (p<0.01). Higher day 3 and 5 MMP-8 levels were associated to mortality at day 14 and 28 (p<0.01) and day 90 (p<0.05). Day 3 MMP-8 cut-off value of 203 ng/ml predicted death within 14 days with an area under the curve (AUC) of 0.70 (95% CI 0.57-0.82) (p<0.01). Day 5 MMP-8 cut-off value of 239 ng/ml predicted death within 14 days with an AUC of 0.76 (95% CI 0.65-0.87) (p<0.001). The results for MMP-8/TIMP-1 resembled that of MMP-8. TIMP-1 had no prognostic impact. In Cox regression analysis day 3 or 5 MMP-8 or day 3 MMP-8/TIMP-1 had no prognostic impact whereas day 5 MMP-8/TIMP-1 predicted mortality within 14 days (HR, 4.71; CI, 95% 1.67-13.3; p<0.01)., Conclusion: MMP-8 and MMP-8/TIMP-1 ratio were high 3-5 days after MS-SAB diagnosis in patients with an infection focus, severe sepsis or mortality within 14 days suggesting that matrix metalloproteinase activation might play a role in severe SAB., Competing Interests: The authors have declared that no competing interests exist.

Objective: During pregnancy, mothers undergoe considerable physiological changes affecting the whole body including periodontal tissues. Susceptibility to gingival inflammation during pregnancy could be mediated by modulation of matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Therefore, the aim of this study was to investigate salivary and gingival crevicular fluid (GCF) levels of MMPs and TIMPs during the second and third trimester of pregnancy and postpartum., Design: Saliva and GCF samples were collected from 96 pregnant women (PW) before and after giving birth. The sixty matched non-pregnant women (N-PW) were recruited as a control group and full-mouth periodontal examination was performed. The levels of MMP-8, MMP-9 and TIMP-1 were determined by immunofluorometric and enzyme-linked immunosorbent assays., Results: The PW group exhibited significantly higher levels of MMP-8 and MMP-9 in their saliva than the N-PW group while corresponding salivary TIMP-1 levels were significantly lower in NPW compared to the postpartum stage. This resulted in significantly higher MMP-8/TIMP-1 and MMP-9/TIMP-1ratio in the saliva from PW before and after birth than in that from N-PW. MMP-8, MMP-9 and TIMP-1 levels were higher in GCF from PW and postpartum than in that from N-PW., Conclusions: MMP-8 and MMP-9 levels in saliva and GCF reflect inflammatory burden during pregnancy. They could be used for monitoring the inflammatory state of gingival tissues during pregnancy., (Copyright © 2021. Published by Elsevier Ltd.)

Introduction: Matrix metalloproteinases (MMPs) have been extensively studied in several malignancies, and myeloperoxidase (MPO) is a promising new prognostic biomarker. We investigated the prognostic value of MMP-8, MMP-9, and MPO, as well as carcinoembryonic antigen (CEA), CA19-9, and C-reactive protein (CRP) in colorectal cancer with operable liver metastases., Methods: This study included 419 patients who underwent liver resection for colorectal metastases at the Helsinki University Hospital between 2000 and 2013. Serum samples were drawn before and 3 months after liver resection. We evaluated associations of MMP-8, MMP-9, MPO, CRP, CEA, and CA19-9 concentrations to disease-free survival (DFS) and overall survival (OS) using the Cox proportional hazards model and Kaplan-Meier log-rank method., Results: In univariate Cox regression analyses, pre- and postoperatively high MMP-8 (HR 1.53, 95% CI: 1.07-2.19, p = 0.021 and HR 1.45, 95% CI: 1.01-2.09, p = 0.044, respectively) associated with worse 10-year OS. Postoperatively high MPO indicated better 5-year DFS (HR 0.70, 95% CI: 0.54-0.90, p = 0.007). Elevated pre- and postoperative CEA and CA19-9 as well as postoperative CRP indicated impaired survival., Conclusions: Pre- and postoperatively high MMP-8 associates with worse 10-year OS, and postoperatively high MPO associates with better 5-year DFS. CEA, CA19-9, and CRP are also prognostic., (© 2021 S. Karger AG, Basel.)

The Objective: This study aimed to analyze active matrix metalloproteinase (aMMP-8) levels in gingival crevicular fluid (GCF), saliva and serum in the context of new criteria of gingivitis and stage 3 grade C periodontitis., The Background: Periodontal disease is an inflammatory process that can result in tooth loss and also is considered a modifying factor for systemic health. Matrix metalloproteinase (MMP)-8 is the major collagenase of periodontal tissue breakdown., Methods: Totally 83 systemically healthy and non-smoker individuals consisting of 23 periodontally healthy, 20 gingivitis and 40 stage 3 periodontitis, were recruited to the study. Clinical periodontal examinations of probing depth (PD), clinical attachment loss (CAL), gingival index (GI), plaque index (PI) and bleeding on probing (BOP) were recorded; and GCF, saliva and serum samples were obtained. aMMP-8 was measured by immunofluorometric assay (IFMA)., Results: GCF and serum aMMP-8 levels were significantly increased in periodontitis and gingivitis compared to healthy ones (P < .001), whereas gingivitis and periodontitis patients showed similar levels of aMMP-8 in GCF and serum (P > .05). Saliva levels of aMMP-8 were higher in periodontitis patients than both gingivitis and healthy individuals (P < .001). There was no significant difference in salivary aMMP-8 levels between gingivitis group and healthy controls (P > .05)., Conclusion: These findings support the involvement of aMMP-8 in periodontal diseases and suggest that its local and systemic levels can reflect stage 3 grade C periodontitis. Moreover, aMMP-8 in GCF and serum seems to have a potential to differentiate between gingivitis and periodontal health., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Periodontal disease is a chronic multifactorial infectious and inflammatory disease associated with several chronic systemic diseases, such as diabetes, cardiovascular diseases (CVD), chronic obstructive pulmonary disease, hypertension, Alzheimer's disease and so on. These same systemic diseases have been associated with severe COVID-19 infections. Several recent studies have suggested hypotheses for the potential association between periodontal disease and severe COVID-19. Periodontal disease is also one of the most prevalent diseases globally. All this supports the importance of good oral health, also in the COVID-19 era. Thus, new strategies and approaches to identify patients at risk of periodontal disease could be beneficial to enhance secondary prevention, especially if targeted to COVID-19 risk groups. Diagnostic biomarkers for periodontal disease have been researched extensively. Potential biomarkers in oral fluid with currently available rapid non-invasive point-of-care technology, such as aMMP-8, could help to extend screening and identification of patients at risk for periodontal disease also to situations and places where professional dental expertise and equipment are limited or unavailable. i.e., nursing and care homes, and rural and distant places. The oral fluid point-of-care technologies could also be useful in the hands of medical professionals (diabetes, CVD, etc.) to identify patients at risk for undiagnosed periodontal disease and to refer them to a dentist for examination and evaluation. Finally, if there is a causality between periodontal disease and severe COVID-19 infections, these point-of-care oral fluid biomarker technologies could possibly also help in the assessment of the risk of deterioration and complications., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Biomarkers represent promising aids in periodontitis, host-mediate diseases of the tooth-supporting tissues. We assessed the diagnostic potential of matrix metalloproteinase-8 (MMP-8), tartrate-resistant acid phosphatase-5 (TRAP-5), and osteoprotegerin (OPG) to discriminate between healthy patients', mild and severe periodontitis sites. Thirty-one otherwise healthy volunteers with and without periodontal disease were enrolled at the Faculty of Dentistry, University of Chile. Periodontal parameters were examined and gingival crevicular fluid was sampled from mild periodontitis sites (M; n = 42), severe periodontitis sites (S; n = 59), and healthy volunteer sites (H; n = 30). TRAP-5 and OPG were determined by commercial multiplex assay and MMP-8 by the immunofluorometric (IFMA) method. STATA software was used. All biomarkers showed a good discrimination performance. MMP-8 had the overall best performance in regression models and Receiver Operating Characteristic (ROC) curves, with high discrimination of healthy from periodontitis sites (area under the curve (AUC) = 0.901). OPG showed a very high diagnostic precision (AUC ≥ 0.95) to identify severe periodontitis sites (S versus H + M), while TRAP-5 identified both healthy and severe sites. As conclusions, MMP-8, TRAP-5, and OPG present a high precision potential in the identification of periodontal disease destruction, with MMP-8 as the most accurate diagnostic biomarker.

Background : This cohort study investigated the role of the active matrix metalloproteinase-8 (aMMP-8) and interleukin-6 (IL-6) as oral fluid biomarkers for monitoring the periodontal degeneration occurring in head and neck cancer (HNC) patients treated by radiotherapy. Research design and methods : Eleven patients, aged 28-74, diagnosed with HNC were included in the study. Complete periodontal and oral examinations were performed pre-radiotherapy and 1 month after radiotherapy. Mouthrinse samples (pre-radiotherapy, after 6 weeks of radiotherapy and 1 month after radiotherapy) were assayed by aMMP-8 point-of-care-kit (PerioSafe®/ORALyzer®) for aMMP-8 and ELISA for IL-6. Results : HNC radiotherapy had a deteriorating impact on the periodontium and a significant impact on periodontal biomarkers aMMP-8 and IL-6 and increased their levels in mouthrinse. Clinical-attachment-loss (CAL) (site of greatest loss: mean = 1.7 mm, range = 1-3 mm) corresponding to rapid progression of periodontitis. There was a positive repeated measures correlation (rmcorr = 0.667) between the aMMP-8 and IL-6 levels. Conclusions : Elevated aMMP-8 levels were observed 1 month after radiotherapy among some HNC patients suggesting a prolonged increased susceptibility to further periodontal tissue destruction. Currently available aMMP-8 point-of-care testing could be useful to monitor and assess quantitatively online and real-time the risk of deterioration of periodontal health during HNC radiotherapy.

The diagnostic accuracy of point-of-care (PoC) applications may be compromised in individuals with additional inflammatory conditions. This cross-sectional study examined the performance of a commercial oral rinse active matrix metalloproteinase-8 (aMMP-8) PoC immunotest in individuals with ( n = 47) and without Crohn's disease (CD) ( n = 41). Oral rinse collected from the participants was analyzed by the PoC immunotest. Molecular forms and fragments of salivary MMP-8 were detected by western immunoblotting. The sensitivity of the immunotest for periodontitis was 60.0% in the CD group and 90.0% in the control group. The respective specificity was 75.0% and 80.0%. In both groups, clinical diagnosis of periodontitis exhibited a significant association with the immunotest results, however, the odds ratio (OR) was more than ten-fold in controls (OR 54.3, 95% CI: 3.1-953, p = 0.006) in comparison to CD patients (OR 5.2, 95% CI: 1.3-21.6, p = 0.022). According to Western immunoblot results, the immunotest MMP-8 positivity was not related to elevated levels of molecular forms and fragments of MMP-8 in the CD group, as in the control group. The diagnostic accuracy of the aMMP-8 PoC oral rinse immunotest is reduced in CD patients, which may be related to lower levels or undetectable complexes., Competing Interests: The authors declare no conflicts of interests related to this study.

Background: This cross-sectional study aims to investigate if a point-of-care (PoC) test of active matrix metalloproteinase-8 (aMMP-8) predicts levels of inflammation amplifier triggering receptor expressed on myeloid cells-1 (TREM-1) and its putative ligand the neutrophil peptidoglycan recognition protein 1 (PGLYRP1) in saliva., Methods: Forty-seven adolescents, aged 15 to 17 years, were tested with aMMP-8 PoC test, which was followed by a full-mouth clinical examination of the assessment of periodontal, mucosal, and oral health. TREM-1 and PGLYRP1 levels were analyzed by ELISA. The immunofluorometric assay (IFMA) specific for aMMP-8 was used as the reference method., Results: Fourteen saliva samples out of a total of 47 showed positivity for aMMP-8 PoC test. Both the TREM-1 and the aMMP-8 (IFMA) levels were significantly elevated among the aMMP-8 PoC test positives compared with the PoC test negatives (P < 0.05). Moreover, aMMP-8 levels assessed by IFMA showed a strong positive correlation with TREM-1 levels in saliva (r = 0.777, P < 0.001). The number of sites with a probing depth of ≥4 mm was significantly lower among the adolescents that had a negative aMMP-8 PoC test result, and TREM-1 levels < 75 pg/mL (P < 0.05). In contrast, adolescents with a positive aMMP-8 PoC test result (i.e., elevated aMMP-8 levels) together with elevated TREM-1 levels had a significantly higher number of periodontal pockets with ≥4 mm (P < 0.001)., Conclusion: The present study validated usability of aMMP-8 PoC test for predicting "proinflammatory" salivary profile and periodontal health status in adolescents., (© 2019 American Academy of Periodontology.)

This study investigated the diagnostic utility of mouthrinse and saliva in aMMP-8 measurements to analyze patients' risk for active periodontal tissue destruction and progression of periodontal disease among 47 adolescents. Results show that measurements from mouthrinse produce better discrimination and should be used instead of saliva measurements., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) contribute to the inflammatory cascade in the cerebrospinal fluid (CSF) during bacterial meningitis. We determined levels of MPO, MMP-8, MMP-9, and tissue inhibitor of metalloproteinase- (TIMP-) 1 in the CSF of children with bacterial meningitis and investigated how these inflammatory mediators relate to each other and to the disease outcomes., Methods: Clinical data and the diagnostic CSF samples from 245 children (median age eight months) with bacterial meningitis were obtained from a clinical trial in Latin America in 1996-2003. MMP-9 levels in the CSF were assessed by zymography, while MMP-8, MPO, and TIMP-1 concentrations were determined with immunofluorometric and enzyme-linked immunosorbent assays., Results: MPO correlated positively with MMP-8 (rho 0.496, P < 0.001) and MMP-9 (rho 0.153, P = 0.02) but negatively with TIMP-1 (rho -0.361, P < 0.001). MMP-8 emerged as the best predictor of disease outcomes: a CSF MMP-8 concentration above the median increased the odds of death 4.9-fold (95% confidence interval 1.8-12.9)., Conclusions: CSF MMP-8 presented as an attractive prognostic marker in children with bacterial meningitis., Competing Interests: Prof. Timo Sorsa is an inventor of US patents 5652223, 5736341, 5866432, and 6143476. All the other authors report no conflict of interest., (Copyright © 2019 Okko Savonius et al.)

Background: The aim of this study was to investigate how different patient-related risk indicators might be associated with the odds of developing subclinical periodontitis in adolescents., Methods: This cross-sectional study included 252 Finnish individuals aged 15 to 16 years, of whom 141 were boys and 111 girls. A specially trained dentist performed clinical examinations: measurements included periodontal indexes (bleeding on probing, visible plaque index, root calculus, and probing depth, smoking by pack-years, periodontal bacteria (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola) and the potential salivary periodontal biomarkers (active matrix metalloproteinase-8 [aMMP-8], polymorphonuclear leukocyte elastase [PMN elastase], and total protein, albumin, immunoglobulin A, immunoglobulin G, and immunoglobulin M). Results were analyzed by ordinal logistic regression, one-way analysis of variance, Fisher exact test, and Kruskal-Wallis H test., Results: The main finding of this study was that subclinical periodontitis in adolescents was statistically significantly associated with elevated salivary aMMP-8 but not with PMN elastase. Also, adolescents with subclinical periodontitis had statistically significantly higher levels of bleeding on probing, root calculus, and dental plaque than adolescents without subclinical periodontitis., Conclusions: We suggest that the main risk factor for subclinical periodontitis in adolescents is the partly calcified, dysbiotic bacterial biofilm, which interacts with the immune defenses of the host; this leads to gingival inflammation and eventually to deepening periodontal pockets. This proinflammatory subclinical periodontitis stage, which represents stage I periodontitis in the new classification, is reflected as elevated salivary aMMP-8 levels in oral fluids., (© 2018 American Academy of Periodontology.)

Aim: This study aimed to investigate the association between salivary levels of myeloperoxidase (MPO), neutrophil elastase (NE), soluble urokinase-type plasminogen activator receptor (suPAR), matrix metalloproteinase (MMP)-8 and tissue inhibitor of matrix metalloproteinases (TIMP)-1 and gingival inflammation development during an experimental gingivitis study., Methods: A three-week experimental gingivitis study was conducted. Clinical recordings of dental plaque biofilm (Modified Quigley Hein Plaque Index, TQHPI) and gingival inflammation (Modified Gingival Index, MGI) were made at specific time points for each of the 42 participants. Salivary levels of MPO, NE, suPAR, MMP-8 and TIMP-1 at the same time points were measured using distinct immunoassays. For data analysis growth curve modelling was employed to account for the time-varying outcome (MGI score) and the time-varying covariates (salivary marker levels, and TQHPI score). Analyses were stratified according to the MGI-score trajectory groups previously identified as 'fast', respectively 'slow' responders., Results: Overall, higher MGI scores were statistically significantly positively associated with higher levels of MPO, MMP-8 and TIMP-1. Stratified analysis according to inflammation development trajectory group revealed higher levels of salivary MPO, MMP-8 and MMP-8/TIMP-1 ratio among the 'fast' responders than among 'slow' responders. None of the investigated salivary protein markers was associated with a 'slow' inflammation development response., Conclusions: Salivary levels of MPO, MMP-8 and TIMP-1 were associated with the extent and severity of gingival inflammation. While the 'fast' gingival inflammation response was associated with increased levels of MPO, MMP-8 and MMP-8/TIMP-1 ratio, the 'slow' response was not associated with any of the salivary protein markers investigated in this study. Neutrophil activity seems to orchestrate a 'fast' gingival inflammatory response among participants previously primed to gingival inflammation., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Biomarkers that could predict malignant transformation of recurrent respiratory papillomatosis (RRP) would be useful in patient follow-up. We investigated whether serum matrix metalloproteinase 8 (MMP-8) and tissue inhibitor of metalloproteinase 1 (TIMP-1) could predict malignant transformation of RRP and whether they associate with survival in laryngeal squamous cell carcinoma (LSCC) without preexisting RRP., Methods: We analyzed serum MMP-8 (S-MMP-8) and serum TIMP-1 (s-TIMP-1) in 114 patients: 55 were treated for RRP and 59 for LSCC without preexisting RRP. Five patients with RRP developed LSCC during follow-up., Results: Elevated S-MMP-8 level in RRP was associated with malignant transformation (P = .01). Compared to patients with RRP, S-MMP-8 in patients with LSCC was significantly higher (P < .001). Increased S-TIMP-1 level in LSCC was associated with poor overall survival (P = .02) and recurrence-free survival (P = .05)., Conclusion: In RRP, high S-MMP-8 may predict malignant transformation. In LSCC, elevated S-TIMP-1 is connected to poor survival., (© 2018 Wiley Periodicals, Inc.)

Aim: To investigate the molecular forms of salivary matrix metalloproteinase (MMP)-8 in relation to periodontitis., Materials and Methods: Molecular forms, degree of activation and fragmentation of neutrophilic and mesenchymal-type MMP-8 isoforms were analysed from salivary samples of 81 subjects with generalized periodontitis, 63 subjects with localized periodontitis and 79 subjects without pocket teeth, by using western-immunoblots with computer quantitation. In addition, human recombinant proMMP-8 was in vitro activated by Treponema denticola chymotrypsin-like protease (Td-CTLP), sodium hypochlorite (NaOCl, 1 mM, oxidant) or amino phenyl mercuric acetate (APMA, 1 mM)., Results: In saliva of periodontitis-affected individuals, MMP-8 is found in multiple forms, that is, complexes, active and pro-forms of neutrophilic and mesenchymal-type MMP-8, and especially 20-27 kDa fragments. The quantity of these fragments was elevated in both localized and generalized forms of periodontitis. Moreover, the tested activators (Td-CTLP, NaOCl and APMA) activated inactive proMMP-8, resulting in fragments of 20-27 kDa, in vitro, and salivary concentrations of T. denticola correlated significantly with salivary levels of fragmented MMP-8., Conclusion: The present results indicate that during the development and progression of periodontitis, MMP-8 appears as activated and fragmented, and treponemal proteases most likely play role in this cascade., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To investigate the impact of anti-rheumatic medications on salivary matrix metalloproteinase (MMP)-8 levels and MMP-8/TIMP (tissue inhibitor of MMPs)-1 ratio in patients with rheumatoid arthritis (RA) and periodontal findings during a 1-year follow-up., Materials and Methods: Salivary MMP-8 was measured by an immunofluorometric assay and TIMP-1 by an enzyme-linked immunosorbent assay of 53 patients with early untreated RA (ERA), naïve to synthetic disease modifying anti-rheumatic drugs (DMARDs), of 28 patients with chronic RA (CRA), candidates for biologic DMARDs and of 43 age- and sex-matched controls. Periodontal health was evaluated by bleeding on probing (BOP), pocket depth (PD), and periodontal inflammatory burden index (PIBI). Examinations were conducted twice for RA patients and once for controls., Results: Salivary MMP-8 level and MMP-8/TIMP-1 ratio associated positively with PIBI in patients with chronic RA (MMP-8: p < 0.001 at baseline, p = 0.002 after follow-up; MMP-8/TIMP-1 ratio p < 0.001, p = 0.003, respectively) and in controls (MMP-8: p = 0.010, MMP-8/TIMP-1 ratio: p = 0.010). Salivary MMP-8 levels were highest at the early stage of RA. The used DMARDs, synthetic or biologic, did not affect salivary MMP-8 concentrations., Conclusions: The use of synthetic or biologic DMARDs did not affect salivary MMP-8 levels in RA patients regardless the duration of RA., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

Despite gastric cancer being rare nowadays in Western countries, it remains one of the leading causes of cancer death worldwide. The course of the disease varies, so the individual gastric cancer patient's prognosis is difficult to determine. The need for new biomarkers is crucial. The aim of this study was to evaluate the prognostic value of serum matrix metalloproteinase-8, serum tissue inhibitor of metalloproteinase-1, and tissue matrix metalloproteinase-8 in patients with gastric cancer. Preoperative serum samples from 233 patients with gastric cancer were retrospectively analyzed. Serum levels of matrix metalloproteinase-8 were analyzed with immunofluorometric assay, and tissue inhibitor of metalloproteinase-1 levels were determined by enzyme-linked immunosorbent assay. We also determined the tissue expression of matrix metalloproteinase-8 in 276 gastric cancer samples by immunohistochemistry. Survival data and death causes came from patient records, the Population Register Center of Finland, and Statistics Finland. Patients with a low (<31 ng/mL) or high (>131 ng/mL) serum matrix metalloproteinase-8 level had a considerably unfavorable prognosis (p = 0.002). Those patients with a high (≥170 ng/mL) serum tissue inhibitor of metalloproteinase-1 level also had a poor prognosis (p < 0.001), and the latter remained significant in multivariable analysis (hazard ratio = 1.85; 95% confidence interval: 1.26-2.72; p = 0.002). The molar ratio of serum matrix metalloproteinase-8 and tissue inhibitor of metalloproteinase-1 levels with low (<0.07) or high (>0.30) molar ratios predicted a worse prognosis (p = 0.020). Tissue matrix metalloproteinase-8 did not influence prognosis. These results suggest that serum matrix metalloproteinase-8, tissue inhibitor of metalloproteinase-1, and the ratio of matrix metalloproteinase-8/ tissue inhibitor of metalloproteinase-1 may prove useful biomarkers for prediction of prognosis in patients with gastric cancer.

The analysis of the disease-specific oral and systemic biomarkers in saliva and oral fluids (i.e., mouth rinse, gingival crevicular fluid (GCF), and peri-implantitis fluid (PISF)) is demanding. Several hosts and microbial factors may influence their expression, release, and levels. The type of saliva/oral fluids utilized for the diagnostics affects the analysis. High sensitivity and specificities together with sophisticated methods and techniques are essential for valuable outcome. We describe here recently developed practical, convenient, inexpensive, noninvasive, and quantitative mouth rinse and PISF/GCF/chair-side/point-of-care (PoC) lateral-flow aMMP-8 immunoassays (PerioSafe and ImplantSafe/ORALyser) to detect, predict, and monitor successfully the course, treatment, and prevention of periodontitis and peri-implantitis, respectively. The tests have been independently and successfully validated to differentiate periodontal and peri-implant health and disease in Finland, Germany, Netherland, Sweden, Turkey, Nigeria, Malawi, and USA. The clinical use of salivary/oral fluid biomarkers to identify oral and systemic conditions requires additional studies utilizing these noninvasive screening, diagnostic, and preventive aMMP-8 PoC/chair-side technologies.

Background: Matrix metalloproteinase-8 (MMP-8) is a protease mainly expressed by neutrophils that cleaves numerous substrates, including collagens and cytokines. We have previously shown that serum MMP-8 levels increase in colorectal cancer (CRC) and correlate with distant metastasis. However, short follow-up in our prospective cohort did not enable survival analyses at the time of the first publication., Methods: Preoperative serum MMP-8 levels were measured by immunofluorometric assay in 271 CRC patients and related to clinicopathological parameters, markers of systemic inflammation (modified Glasgow Prognostic Score, mGPS; serum levels of C-reactive protein (CRP), albumin and 13 cytokines), the density of six types of tumour-infiltrating immune cells and survival., Results: Increased MMP-8 levels associated with higher mGPS and higher serum levels of CRP and several cytokines, including IL-1ra, IL-7 and IL-8 (p < 0.001 for all). Serum MMP-8 negatively correlated with tumour-infiltrating mast cells (invasive margin: p = 0.005, tumour centre: p = 0.010). The patients with high-serum MMP-8 levels (>100 ng/mL) had poor cancer-specific survival, independent of tumour stage, grade, lymphatic invasion, patient age, BRAF VE1 immunohistochemistry, mismatch repair deficiency, Immunoscore and mGPS (multivariate HR 2.12, 95% CI 1.21-3.71, p = 0.009)., Conclusions: High-serum MMP-8 levels are associated with systemic inflammation and adverse outcome in CRC.

Background: Almost all of the extracellular matrix (ECM) components can be degraded by the endoproteinases matrix metalloproteinases (MMPs). Important regulators of MMPs, and thereby of the extracellular environment, are tissue inhibitors of metalloproteinases (TIMPs), and especially TIMP-1. Early tumor development, as well as distant metastasis, may be results of an MMP/TIMP ratio imbalance altering the ECM. MMPs are elevated in several inflammatory conditions. Our aim is to investigate the prognostic role of MMP-8, - 9, and TIMP-1 in colorectal cancer (CRC) and their relationship to inflammation., Methods: We included 337 colorectal cancer patients and 47 controls undergoing surgery at Helsinki University Hospital in Finland, 1998-2011. Serum levels of MMP-8 and plasma levels of C-reactive protein (CRP) were determined with a time-resolved immunofluorometric assay (IFMA), and MMP-9 and TIMP-1 with commercial enzyme-linked immunosorbent assay (ELISA) kits. Association and correlation analyses were performed with the Mann-Whitney U, Kruskal-Wallis, and Spearman rank correlation tests. Survival curves were constructed according to the Kaplan-Meier method and compared with the log-rank test., Results: Among patients with advanced disease, serum levels of MMP-8 and TIMP-1 were elevated. CRC patients with high MMP-8 (HR (hazard ratio) 1.72, 95% confidence interval (CI) 1.17-2.52, P = 0.005) and those with high TIMP-1 (HR 1.80, 95% CI 1.23-2.64, P = 0.002) had worse prognoses. MMP-9 level failed to serve as a prognostic factor. In multivariable survival analysis, Dukes stage, and low MMP-9/TIMP-1 molar ratio (HR 0.46, 95% CI 0.33-0.98, P = 0.042) were independently predicted prognosis. A weak correlation between CRP and MMP-8 (r S  = 0.229, P < 0.001), and TIMP-1 (r S  = 0.280, P < 0.001) was noted. Among patients showing no systemic inflammatory response, MMP-8 (HR 1.66, 95% CI 1.10-2.53, P = 0.017) and TIMP-1 (HR 1.59, 95% CI 1.05-2.42, P = 0.029) were prognostic factors., Conclusions: MMP-8 and TIMP-1 in serum, but not MMP-9, identified CRC patients with bad prognosis. Among patients showing no systemic inflammatory response, MMP-8 and TIMP-1 may associate with poor prognosis.

Background and Aims: Matrix metalloproteinase (MMP)-8 and myeloperoxidase (MPO) may contribute to cerebral damage in acute ischemic stroke. We tested the hypothesis that levels of MPO, MMP-8 and the ratio between MMP-8 and its regulator, tissue inhibitor of metalloproteinase (TIMP-1), are increased in acute ischemic stroke and its etiologic subgroups and they correlate with stroke severity., Methods: In a cross-sectional case-control study, serum concentrations of MMP-8, MPO and TIMP-1 were assessed within 24 h after admission in 470 first-ever ischemic stroke patients and 809 age- and sex-matched controls, randomly selected from the population. Odds ratios (OR) per decade of log transformed dependent variables were calculated and adjusted for age, sex and vascular risk factors., Results: Levels of MMP-8 (OR 4.9; 95% CI 3.4-7.2), MMP-8/TIMP-1 ratio (3.0; 2.2-4.1) and MPO (6.6; 4.0-11.0) were independently associated with ischemic stroke. MMP-8 levels differed between etiologic stroke subgroups (p = 0.019, ANOVA), with higher levels in cardioembolic stroke and stroke due to large vessel disease, and lower levels in microangiopathic stroke. MMP-8, MMP-8/TIMP-1 ratio and MPO (p < 0.001) concentrations showed positive associations with stroke severity independent of stroke etiology., Conclusions: Concentrations of serum neutrophil markers are increased after ischemic stroke and associate with stroke severity and etiology. The value of these biomarkers in diagnostics and prognostics is worth being evaluated., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: Matrix metalloproteinase 8 (MMP-8) is a proinflammatory enzyme expressed mainly by neutrophils. Elevated serum and plasma concentrations of MMP-8 are associated with the risk for and outcome of cardiovascular diseases (CVDs). The origin of circulating MMP-8 is not completely clear., Methods and Results: We performed a genome-wide association study of serum MMP-8 levels in 2 populations comprising altogether 6049 individuals. Moreover, we studied whether MMP-8-associated variants are linked to increased risk of CVDs and overall mortality in >20 000 subjects. The strongest association with serum MMP-8 was found in locus 1q31.3, containing the gene for complement factor H (lead single nucleotide polymorphism: rs800292; P =2.4×10 -35 ). In functional experiments, activation of the alternative pathway of complement in the carriers of rs800292 minor allele (Ile62 in factor H) led to decreased release of MMP-8 from neutrophils compared with the major allele (Val62 in factor H). Another association was detected in 1q21.3, containing genes S100A8 , S100A9 , and S100A12 (strongest association: rs1560833; P =5.3×10 -15 ). The minor allele of rs1560833 was inversely associated with CVD (odds ratio [95% confidence interval]: 0.90 [0.82-0.99]; P =0.032) and the time to incident CVD event (hazard ratio [95% confidence interval]: 0.91 [0.84-0.99]; P =0.032) in men but not in women., Conclusions: According to our results, the activation of the alternative pathway of the complement system strongly contributes to serum MMP-8 concentration. Genetic polymorphism in S100A9-S100A12-S100A8 locus affects serum and plasma MMP-8 and shows a suggestive association with the risk of CVDs. Our results show that genetic variation determines a significant portion of circulating MMP-8 concentrations., (© 2017 American Heart Association, Inc.)

Background: A persistent human papillomavirus (HPV) infection is a prerequisite for a HPV related cancer to develop. Asymptomatic, persistent HPV infections are not only found in genital tract, but also on oral mucosa. Oral HPV persistence may be associated with behavioural factors, but data on the role of innate immunity in oral HPV infections are still limited., Objectives: Salivary concentrations of matrix metalloproteinases MMP-8 and MMP-9, tissue inhibitor of MMPs (TIMP-1), myeloperoxidase, and serum concentrations of MMP-8 were analysed in women with a persistent oral HPV infection and, as a control, in women who remained HPV DNA-negative during a 6-year follow-up. The effects of smoking, lactation and alcohol use on the salivary and serum parameters were assessed, too., Study Design: A nested case-control setting was used to select a subgroup of 57 women with a persistent oral HPV infection and 102 controls from the Finnish Family HPV Study., Results: The salivary MMP-8/TIMP-1 molar ratio was lower in HPV DNA-positive women than in controls (p=0.036). The difference was more pronounced in non-smoking women, in this group also the salivary MMP-8 levels differed (p=0.047). There was a correlation between the salivary concentrations of myeloperoxidase and MMP-8 (r=0.567, p<0.001) or MMP-9 (r=0.234, p=003), but no correlation between salivary and serum MMP-8 levels. The MMP-9 concentration and the MMP-9/TIMP-1 molar ratio were significantly lower in smokers than in non-smokers (p=0.020 and p=0.003, respectively)., Conclusions: Persistent oral HPV infection was associated with a low salivary MMP-8 concentration indicating eventually a failure in oral anti-inflammatory defence., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Background Extracellular matrix degrading proteases and their regulators play an important role in atherogenesis and subsequent plaque rupture leading to acute cardiovascular manifestations. Design and methods In this prospective cohort study, we investigated the prognostic value of circulating matrix metalloproteinase-8, tissue inhibitor of matrix metalloproteinase-1 concentrations, the ratio of matrix metalloproteinase-8/ tissue inhibitor of matrix metalloproteinase-1 and, for comparison, myeloperoxidase and C-reactive protein concentrations for incident cardiovascular disease endpoints. The population-based FINRISK97 cohort comprised 7928 persons without cardiovascular disease at baseline. The baseline survey included a clinical examination and blood sampling. During a 13-year follow-up the endpoints were ascertained through national healthcare registers. The associations of measured biomarkers with the endpoints, including cardiovascular disease event, coronary artery disease, acute myocardial infarction, stroke and all-cause death, were analysed using Cox regression models. Discrimination and reclassification models were used to evaluate the clinical implications of the biomarkers. Results Serum tissue inhibitor of matrix metalloproteinase-1 and C-reactive protein concentrations were associated significantly with increased risk for all studied endpoints. Additionally, matrix metalloproteinase-8 concentration was associated with the risk for a coronary artery disease event, myocardial infarction and death, and myeloperoxidase concentration with the risk for cardiovascular disease events, stroke and death. The only significant association for the matrix metalloproteinase-8/ tissue inhibitor of matrix metalloproteinase-1 ratio was observed with the risk for myocardial infarction. Adding tissue inhibitor of matrix metalloproteinase-1 to the established risk profile improved risk discrimination of myocardial infarction ( p=0.039) and death (0.001). Both matrix metalloproteinase-8 (5.2%, p < 0.001) and tissue inhibitor of matrix metalloproteinase-1 (12.9%, p < 0.001) provided significant clinical net reclassification improvement for death. Conclusions Serum matrix metalloproteinase-8 and tissue inhibitor of matrix metalloproteinase-1 can be considered as biomarkers of incident cardiovascular disease events and death.

Background: Vitamin D is a potent immunomodulator and may play a role in the development of the fetal innate immune functions. The aim of our study was to evaluate inflammatory markers in cord blood of healthy newborns in relation to vitamin D status at birth., Methods: We studied the concentrations of inflammatory markers, matrix metalloproteinase 8 (MMP-8) and high sensitivity CRP (hs-CRP), and 25-hydroxyvitamin D (25(OH)D) in cord blood of 939 healthy term infants born to mothers of Caucasian origin. We evaluated perinatal factors that affect the concentrations of MMP-8 and hs-CRP, and further explored associations between cord blood 25(OH)D and these inflammatory biomarkers., Results: Majority (99%) of the cohort was vitamin D sufficient (>50 nmol/l or 20 ng/ml). We observed a positive correlation between cord blood 25(OH)D and MMP-8 concentrations, and between 25(OH)D and hs-CRP concentrations. After adjustment for potential confounders (parity, antenatal antibiotic treatment, gestational age, mode of delivery, and maternal prepregnancy BMI), the association of 25(OH)D with MMP-8 and hs-CRP remained significant., Conclusion: Cord blood 25(OH)D correlates with inflammatory markers MMP-8 and hs-CRP. The findings may reflect the diverse immunomodulatory functions of vitamin D in the innate immune response of the newborn.

Background: In periodontitis, genetics and smoking play important roles in host immune system response. The aim of this study is to determine whether the genetic background of initial periodontitis and caries could be detected using an active matrix metalloproteinase (aMMP)-8 chairside test in Finnish adolescents., Methods: Forty-seven participants gave approval for analysis of both oral fluid collection and DNA. An aMMP-8 chairside test was performed on participants (adolescents aged 15 to 17 years), and full-mouth clinical parameters of oral health were assessed including periodontal, oral mucosal, and caries status in Eastern Finland from 2014 to 2015. DNA was extracted from oral fluid samples and genotyped for 71 polymorphisms in 29 candidate genes for periodontitis. Results were analyzed using a logistic regression model. P values were corrected for multiple testing using false discovery rate (<0.05)., Results: aMMP-8 chairside test positivity and three or more ≥4 mm pockets were associated with vitamin D receptor (VDR) (rs2228570, P = 0.002, q = 0.04) and MMP3 (rs520540, rs639752, rs679620, P = 0.0009, 0.003, 0.003, q = 0.04, respectively). None of the other single-nucleotide polymorphisms studied showed a significant association with the aMMP-8 chairside test and at least one caries lesion positivity., Conclusion: Genetic polymorphisms of MMP3 and VDR are linked to initial periodontitis in Finnish adolescents, and the aMMP-8 chairside test can eventually detect initial periodontitis in young patients with predisposing genetic background.

The development of several life-long diseases, such as coronary heart disease, is affected by low-grade systemic inflammation. Data on the potential long-term health effects of chronic tonsillitis are limited. Many inflammatory conditions present with enhanced systemic matrix metalloproteinase (MMP)-8 response. In head and neck cancer, high plasma level of tissue inhibitor of metalloproteinase (TIMP)-1 predicts poor prognosis. We analyzed S-MMP-8 with immunofluorometric assay and S-TIMP-1 with an immunosorbent assay in 175 consecutive patients undergoing tonsillectomy for benign tonsillar disease, and in 33 control patients with tonsillar squamous cell carcinoma. Tonsillar human papillomavirus (HPV) status was determined by PCR. In patients with benign tonsillar disease, chronic tonsillitis without hypertrophy was associated with enhanced systemic MMP-8 response. Compared to patients with benign tonsillar disease, patients with tonsillar squamous cell carcinoma had significantly higher concentrations of S-MMP-8 and S-TIMP-1. Neither S-MMP-8 nor S-TIMP-1 correlated with tonsillar HPV positivity.

Background: Matrix metalloproteinase 8 (MMP-8) is the most potent type-I collagen protease. Such collagen mainly constitutes the transient fibrosis in takotsubo cardiomyopathy (TTC) endomyocardial biopsies. High MMP-8 and tissue-inhibitor of matrix metalloproteinase-1 (TIMP-1) levels are implicated in acute coronary syndrome (ACS). We compared MMP-8 and TIMP-1 levels in consecutive TTC and ACS patients, and their association to TTC severity., Methods and Results: In 45 acute serum samples of TTC, 2072 ACS and 1000 controls, TIMP-1 differed between ACS 146.7ng/mL (115.0-186.3) (median (interquartile range)), TTC 115.7 (94.3-137.7) and controls 80.9 (73.2-90.4), (p<0.0001). MMP-8 levels were similar between ACS and TTC. In receiver-operating characteristics analysis, TIMP-1 differentiated TTC from ACS with an area under the curve (AUC) of 0.679 (p<0.0001) surpassing troponin T (TnT) at 0.522 (p = 0.66). Compared to other differing factors (age, sex, smoking), TIMP-1 improved diagnostic specificity and sensitivity from AUC of 0.821 to 0.844 (p = 0.007). The MMP8/TIMP-1 molar ratio differentiated normal ejection fraction (EF) at 0.27 (0.13-0.51) from decreased EF<50% at 0.08 (0.05-0.20), (p = 0.04) in TTC, but not in ACS., Conclusions: Even with other differing factors considered, TIMP-1 differentiated TTC from ACS better than TnT. In TTC, the low MMP-8/TIMP-1 molar ratio may reflect decreased proteolysis and increased transient fibrosis, perhaps in part explaining the left-ventricle impairment.

Background: This study evaluates levels of matrix metalloproteinase (MMP)-8, MMP-9, and tissue inhibitor of MP-1 (TIMP-1) in biofluids of women with gestational diabetes mellitus (GDM) and systemically healthy counterparts with different statuses of periodontal health., Methods: Seventy-one women with GDM and gingivitis (Gg), 30 women with GDM and healthy periodontium (Gh), 28 systemically and periodontally healthy women (Hh), and 37 systemically healthy women with gingivitis (Hg) were evaluated. MMP-8, MMP-9, and TIMP-1 levels were determined in gingival crevicular fluid (GCF), saliva, and serum by immunofluorometric and enzyme-linked immunosorbent assays. Full-mouth clinical periodontal parameters were recorded., Results: GCF and serum MMP-8 concentrations, serum MMP-9 concentrations, and serum MMP-8/MMP-1 and MMP-9/MMP-1 molar ratios were significantly higher in Gg compared with Hg group (P <0.05). Serum MMP-8 levels and salivary TIMP-1 levels were higher in Gh compared with Hg group (P <0.05) whereas salivary MMP-8/TIMP-1 molar ratio was lower in Gh compared with Hg group (P <0.05). Elevated concentrations of GCF MMP-8 and MMP-9 were found in Gg compared with Gh group (P <0.05). Significant correlations were found between local levels of biomarkers and clinical periodontal parameters in only GDM group., Conclusion: GDM may modulate both local and circulating levels of MMP-8 especially when associated with gingivitis.

Background: Obesity has been recognized as a state of subclinical inflammation resulting in a loss of insulin receptors and decreased insulin sensitivity. We here studied in vivo the role of circulating matrix metalloproteinase-8 (MMP-8) among young healthy twin adults. Also, in vitro analysis of the cleavage of human insulin receptor (INSR) by MMP-8 was investigated as well its inhibition by doxycycline and other MMP-8 inhibitor, Ilomastat/GM6001, which are broad-spectrum MMP inhibitors., Materials and Methods: We analysed serum MMP-8 levels by a time-resolved immunofluorometric assay in obese (n = 34), overweight (n = 76) and normal weight (n = 130) twin individuals. The effect of MMP-8 on INSR and the effects of synthetic MMP-8 inhibitors, doxycycline and Ilomastat/GM6001, were studied by SDS-PAGE., Results: We found that in obese individuals relative to normal weight individuals, the serum MMP-8 levels and MMP-8/TIMP-1 ratio were significantly increased (P = 0·0031 and P = 0·031, respectively). Among normal weight and obese individuals, also smoking significantly increases serum MMP-8 and MMP-8/TIMP-1 ratio. In vitro, we found that INSR was degraded by MMP-8 and this was inhibited by doxycycline and Ilomastat/GM6001., Conclusions: Obesity associated with elevated circulating MMP-8 found among young adults may contribute to progression of insulin resistance by cleaving INSR. This INSR cleavage by MMP-8 can be inhibited by synthetic MMP-8 inhibitors such as doxycycline. In addition to obesity, also smoking independently explained increased MMP-8 levels. Our results suggest that MMP-8 is an essential mediator in systemic subclinical inflammatory response in obesity, and a potential drug target., (© 2016 Stichting European Society for Clinical Investigation Journal Foundation.)

Matrix metalloproteinase-8 is a promising candidate biomarker for oral fluid (gingival crevicular fluid, peri-implant sulcular fluid and saliva) and mouthrinse chair-side/point-of-care diagnostics to predict, diagnose and determine the progressive phases of episodic periodontitis and peri-implantitis, as well as to monitor the treatments and medications. Matrix metalloproteinase-8 can be used alone or together with interleukin-1beta and Porphyromonas gingivalis to calculate cumulative risk score at the subject level as a successful diagnostic tool, especially in large-scale public health surveys, in which a thorough periodontal examination is not feasible., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: Matrix metalloproteinases MMP-2 and MMP-9 have been associated with juvenile parotitis. However, the role of MMP-8 has not been addressed previously. This work focuses on salivary MMP-8 and -9 levels in juvenile parotitis., Methods: During a five-year period at Helsinki University Hospital, a tertiary care hospital, 41 patients aged 17 or under, were identified as having parotitis; from 36 of these patients, saliva samples were collected for MMP-8 IFMA (time-resolved immunofluorometric assay) analyses. Control saliva samples were collected from 34 age- and gender-matched children admitted for an elective surgery who had no history of parotitis. For comparison, salivary levels of MMP-9, tissue inhibitor of matrix metalloproteinase (TIMP-1), MMP-8/TIMP-1 ratio, human neutrophil elastase (HNE), and myeloperoxidase (MPO) were analyzed by ELISA. Additionally, salivary MMP-8 levels were compared to historical saliva samples from 18 adult gingivitis patients as well as to 10 healthy adult controls., Results: The median (25%, 75% percentile) MMP-8 concentration in saliva of parotitis patients was significantly lower than MMP-8 concentration in saliva of their controls [50.4ng/ml (37.5, 72.9) vs. 148.5ng/ml (101.2, 178.5) p<0.0001] and lower than in patients with gingivitis [347.9ng/ml (242.6, 383.2) p<0.0001] or healthy adult controls [257.2ng/ml (164.9, 320.7) p<0.0001]. The MMP-8/TIMP-1 ratio was lower than in controls [0.13 (0.05-0.02) vs. 0.3 (0.17-0.46) p<0.0001]. The median MMP-9 concentration in saliva of parotitis patients was significantly higher than in controls [143.9ng/m (68.8-189.0) vs. 34.9ng/ml (16.3-87.6) p<0.0001]. Neither HNE, MPO, nor TIMP-1 alone separated the patients from the control groups., Conclusions: MMP-9 was up-regulated in juvenile parotitis saliva, suggesting that MMP-9 may play a destructive role in juvenile parotitis, as others have suggested. The present novel findings reveal a decreased salivary MMP-8 concentration, suggesting that MMP-8 may reflect in juvenile parotitis down-regulated or anti-inflammatory immune characteristics., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: The aim of the present study is to compare periodontal inflammatory burden related to the salivary matrix metalloproteinase (MMP)-8 concentration among patients with chronic kidney disease (CKD) at the predialysis stage., Methods: Salivary samples from 118 predialysis patients were assayed for MMP-8 by immunofluorometric assay. Of the patients, 43 (36%) had diabetic nephropathy, whereas 75 (64%) had other kidney disease. Clinical and radiographic oral health examination was made at Helsinki University Hospital. Oral and general health data including laboratory findings were recorded from hospital records, and the periodontal inflammatory burden index (PIBI) and the total dental index (TDI) were calculated. Results were analyzed with cross tabulation, Pearson χ(2) test, and Mann-Whitney U test., Results: Results included elevated PIBI, increased TDI, and two or more sites with ≥ 6 mm or deeper periodontal pocket, associated with elevated salivary MMP-8 concentrations (P < 0.05 in all associations). The diabetic nephropathy group and patients with high hemoglobin A1c (HbA1c) values (≥ 6.5%, ≥ 48 mmol/mol) exerted slightly elevated median salivary MMP-8 values compared with the other CKD group or regarding patients with HbA1c values < 6.5%, but these differences were not statistically significant., Conclusions: Elevated salivary MMP-8 associated significantly with more severe oral/periodontal inflammatory burden among patients with CKD at the predialysis stage. Thus, salivary MMP-8 analysis could give adjunctive information regarding oral health.

This study aimed to investigate the levels of matrix metalloproteinase-8 (MMP-8) and tissue inhibitors of MMP-1 (TIMP-1) in saliva and serum samples of women with polycystic ovary syndrome (PCOS; n = 80) and matched systemically healthy controls (n = 45), with varying degrees of gingival inflammation. Salivary levels of MMP-8 and the MMP-8/TIMP-1 ratio were significantly elevated in women with PCOS, who also exhibited more gingivitis than systemically healthy women. No major changes were observed in salivary TIMP-1 levels with regard to PCOS. Serum levels of MMP-8 and the MMP-8/TIMP-1 ratio were significantly higher in women with PCOS, irrespective of the presence of gingivitis, while there were no differences in TIMP-1 levels. A positive correlation was indicated between probing depth, bleeding on probing, plaque index and salivary or serum MMP-8 levels or MMP-8/TIMP-1 ratio in the case of PCOS, while a negative such correlation was revealed for TIMP-1 in systemically healthy women. Increased levels of MMP-8 in saliva and serum seem to be more pronounced in women with PCOS, and potentiated in the presence of gingival inflammation. Alterations in MMP/TIMP system triggered by local and systemic inflammation may be implicated in the pathogenesis of PCOS, or the deterioration of its clinical presentation., (© The Author(s) 2015.)

Background and Objective: Matrix metalloproteinase (MMP) -8, -9 and myeloperoxidase (MPO) are inflammatory mediators. The potential associations between MMP-8, -9, MPO and their abilities to reflect cardiovascular risk remains to be evaluated in saliva. The objective of this study was to investigate the levels and associations of salivary MMP-8, -9, MPO and tissue inhibitors of metalloproteinase (TIMP)-1 in myocardial infarction (MI) patients and controls with or without periodontitis., Materials and Methods: 200 patients with a first MI admitted to coronary care units in Sweden from May 2010 to December 2011 and 200 controls matched for age, gender, residential area and without previous MI were included. Dental examination and saliva sample collection was performed 6-10 weeks after the MI in patients and at baseline in controls. The biomarkers MMP -8, -9, MPO and TIMP-1 were analyzed by time-resolved immunofluorescence assay (IFMA), Western blot and Enzyme-Linked ImmunoSorbent Assay (ELISA)., Results: After compensation for gingivitis, gingival pockets and smoking, the mean salivary levels of MMP-8 (543 vs 440 ng/mL, p = 0.003) and MPO (1899 vs 1637 ng/mL, p = 0.02) were higher in non-MI subjects compared to MI patients. MMP-8, -9 and MPO correlated positively with clinical signs of gingival/periodontal inflammation while TIMP-1 correlated mainly negatively with these signs. The levels of latent and active forms of MMP-8 did not differ between the MI and non-MI groups. Additionally, MMP-8, MPO levels and MMP-8/TIMP-1 ratio were significantly higher in men compared to women with MI., Conclusions: This study shows that salivary levels of the analyzed biomarkers are associated with periodontal status. However, these biomarkers could not differentiate between patients with or without a MI. These findings illustrate the importance to consider the influence of oral conditions when analyzing levels of inflammatory salivary biomarkers.

Background: Different gingival crevicular fluid (GCF) matrix metalloproteinase (MMP)-8 response patterns were studied among non-smoking and smoking patients with chronic periodontitis (CP) and generalized aggressive periodontitis (GAgP) to test the utility of GCF MMP-8 levels predicting the site-level treatment outcome., Methods: Data from four independent longitudinal studies were combined. Altogether, the studies included 158 periodontal sites from 67 patients with CP and 32 patients with GAgP, and GCF samples were collected at baseline, after the treatment, and during the 6-month maintenance period. All GCF samples were analyzed by immunofluorometric assay for MMP-8. Different site-level MMP-8 response patterns were explored by the cluster analysis. Most optimal MMP-8 cutoff levels were searched with receiver operating characteristic analyses, and the predictive utility of defined levels was tested., Results: Distinct types of MMP-8 response patterns were found in both smokers and non-smokers. MMP-8 levels exceeding the optimal cutoff levels separately defined for smokers and non-smokers indicated increased risk for compromised treatment outcome at baseline and during the maintenance period. Seventy-one percent of non-smokers (positive likelihood ratio of 4.22) and 88% of smokers (positive likelihood ratio of 5.00) with positive test results at both baseline and the maintenance period had compromised treatment outcome. The double-positive result indicated 46% and 39% point risk increase for the compromised outcome, respectively., Conclusion: GCF MMP-8 analysis with defined cutoff levels could be used to predict the site-level treatment outcome and for longitudinal monitoring of the disease status during the maintenance period.

Introduction: Matrix metalloproteinases (MMPs) -8 and -9 are released from neutrophils in acute inflammation and may contribute to permeability changes in burn injury. In retrospective studies on sepsis, levels of MMP-8, MMP-9, and tissue inhibitor of metalloproteinase-1 (TIMP-1) differed from those of healthy controls, and TIMP-1 showed an association with outcome. Our objective was to investigate the relationship between these proteins and disease severity and outcome in burn patients., Methods: In this prospective, observational, two-center study, we collected plasma samples from admission to day 21 post-burn, and burn blister fluid samples on admission. We compared MMP-8, -9, and TIMP-1 levels between TBSA<20% (N = 19) and TBSA>20% (N = 30) injured patients and healthy controls, and between 90-day survivors and non-survivors. MMP-8, -9, and TIMP-1 levels at 24-48 hours from injury, their maximal levels, and their time-adjusted means were compared between groups. Correlations with clinical parameters and the extent of burn were analyzed. MMP-8, -9, and TIMP-1 levels in burn blister fluids were also studied., Results: Plasma MMP-8 and -9 were higher in patients than in healthy controls (P<0.001 and P = 0.016), but only MMP-8 differed between the TBSA<20% and TBSA>20% groups. MMP-8 and -9 were not associated with clinical severity or outcome measures. TIMP-1 differed significantly between patients and controls (P<0.001) and between TBSA<20% and TBSA>20% groups (P<0.002). TIMP-1 was associated with 90-day mortality and correlated with the extent of injury and clinical measures of disease severity. TIMP-1 may serve as a new biomarker in outcome prognostication of burn patients.

Matrix metalloproteinases (MMPs) are important enzymes in tissue turnover and various inflammatory processes. In this study, it was evaluated whether serum MMP-8 can predict the response to adjuvant interferon alfa-2b (IFN-α) therapy in patients with operated high-risk cutaneous melanoma. Pre-treatment sera from 460 patients with stage IIB-IIIC melanoma were analyzed for MMP-8. The patients were randomized after surgery to adjuvant IFN-α for 12 or 24 months (n = 313) or observation only (n = 147). The median serum MMP-8 level was used to classify the patients into a low MMP-8 (n = 232) and a high MMP-8 (n = 228) group. In the high MMP-8 subgroup, IFN-α therapy significantly improved relapse-free survival (RFS). RFS was 36.8 months in patients with high MMP-8 levels receiving IFN-α therapy, whereas RFS for those with high MMP-8 levels with observation only was 10.6 months (P = 0.027). Median overall survival for patients with high MMP-8 and observation only was 36.7 versus 71.7 months in those receiving IFN-α (P = 0.13). In a multivariate model, IFN-α therapy was a significant predictor of favorable RFS (HR 0.74; 95 % CI 0.55-0.99; P = 0.048), after adjustment for pre-treatment MMP-8 (HR 1.17; 95 % CI 0.88-1.55; P = 0.28), gender (HR 1.16; 95 % CI 0.86-1.56; P = 0.32), age (HR 1.00; 95 % CI 1.00-1.02; P = 0.12), ulceration (HR 1.09; 95 % CI 0.81-1.46; P = 0.58), and the presence of node metastases (HR 1.36; 95 % CI 1.17-1.58; P < 0.0001). In conclusion, patients with high serum MMP-8 levels may benefit from adjuvant IFN-α therapy, but this observation should be further investigated.

Background: The aim of the present study is to investigate matrix metalloproteinase (MMP)-8 and tissue inhibitor of MMP-1 (TIMP-1) gene polymorphisms in generalized aggressive periodontitis (GAgP) and to assess the effects of MMP-8 and TIMP-1 genotypes on the outcomes of non-surgical periodontal therapy., Methods: Genomic DNA was obtained from peripheral blood of 100 patients with GAgP and 167 periodontally healthy controls. MMP-8 +17 C/G, -799 C/T, -381 A/G and TIMP-1 372 T/C, *429 T/G polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism. Patients with GAgP received non-surgical periodontal therapy and were followed for 6 months. Clinical periodontal parameters and gingival crevicular fluid (GCF) samples were collected at baseline and at follow-up visits. GCF biomarkers were analyzed by immunofluorescence assay and enzyme-linked immunosorbent assay., Results: Distribution of the MMP-8 -799 C/T genotypes was significantly different between the GAgP and control groups (P <0.005). TIMP-1 372 T/C and *429 T/G genotypes in males were also significantly different between study groups (P <0.004). GCF MMP-8 levels decreased until 3 months after non-surgical therapy compared with baseline in T and G alleles, as well as G and C allele carriers (P <0.0125), whereas no significant decreased was observed in non-carriers (P >0.0125)., Conclusion: On the basis of the present findings, it can be suggested that MMP-8 -799 C/T and TIMP-1 372 T/C, *429 T/G gene polymorphisms in males may be associated with the susceptibility to GAgP in the Turkish population.

Background: Extracellular matrix-degrading proteinases are upregulated in atherosclerotic lesions and can contribute to subsequent pathological events. In the present nested case-control study, we investigated the association of serum concentrations of matrix metalloproteinases MMP-7, MMP-8, and MMP-13, tissue inhibitor of metalloproteinase-1 (TIMP-1), and neutrophil elastase (NE) with incident cardiovascular disease (CVD) events., Design: The FINRISK97 cohort included 8090 persons with no history of CVD. During the 10-year follow up, 471 incident CVD cases were ascertained and for them, three individually matched controls (n = 1413) were selected. The CVD events included myocardial infarction, stroke, coronary revascularization, and CVD death., Results: Compared to the controls, the cases had significantly higher serum mean concentrations of MMP-7, MMP-8, and TIMP-1, as well as MMP-7/TIMP-1 ratio. In multivariate analyses adjusted for CVD risk factors, MMP-7, MMP-8, TIMP-1, and MMP-8/TIMP-1 ratio were associated with the risk for incident CVD: OR 1.16 (95% CI 1.03-1.31), OR 1.13 (95% CI 1.01-1.26), OR 1.16 (95% CI 1.02-1.31), and OR 1.13 (95% CI 1.00-1.27) respectively, per SD-increase of log-transformed unit. The associations, however, attenuated into non-significant after adjusting for C-reactive protein (CRP) concentrations., Conclusions: MMP-7 and MMP-8, which are upregulated during inflammation, can form a proinflammatory tissue destructive cascade. They can be regarded as risk factors, and thus as potential biomarkers for incident CVD. The balance between these MMPs and their tissue inhibitor may indicate vulnerability to plaque rupture., (© The European Society of Cardiology 2012.)

Background: The aim of the present study was to evaluate the effect of adjunctive chlorhexidine (CHX) mouthrinse on gingival crevicular fluid (GCF) MMP-8 and TIMP-1 levels in plaque-associated gingivitis., Methods: A total of 50 gingivitis patients were included in the present study. In addition to daily plaque control, CHX group rinsed with CHX, while placebo group rinsed with placebo mouthrinse for 4 weeks. GCF samples were collected, and clinical parameters including plaque index, papillary bleeding index, calculus index and pocket depth were recorded at baseline and 4 weeks. GCF MMP-8 and TIMP-1 levels were determined by immunofluorometric assay (IFMA) and enzyme-linked immunosorbent assay (ELISA), respectively., Results: In both groups, GCF MMP-8 levels of anterior and posterior sites at four weeks were not different from baseline (p > 0.05). There were no significant differences in GCF MMP-8 levels between the study groups at four weeks (p > 0.05). GCF TIMP-1 levels of anterior and posterior sites at four weeks were higher compared to baseline in both groups (p < 0.05). There was no significant difference in GCF TIMP level between the study groups at four weeks (p > 0.05)., Conclusions: CHX usage had no significant effects on the GCF MMP-8 and TIMP-1 levels in plaque-associate gingivitis. However, daily plaque control resulted in the increase of GCF TIMP-1 levels regardless of CHX usage.

Background: Matrix metalloproteinases (MMPs) likely have an important role in the pathophysiology of acute lung injury. In a recent study, high matrix metalloproteinases (MMP-8) levels in tracheal aspirates of pediatric acute respiratory distress syndrome (ARDS) patients were associated with worse outcome. In patients with sepsis, an imbalance between MMPs and their tissue inhibitors (TIMPs) has been associated with impaired survival. We hypothesized that the elevated systemic MMP-8 and TIMP-1 are associated with worse outcome in acute respiratory failure., Methods: This was a substudy of the observational FINNALI study conducted in 25 Finnish intensive care units over an 8-week period. All patients older than 16 years requiring mechanical ventilation for >6 hours were included. MMP-8 and TIMP-1 levels were analyzed from blood samples taken on enrollment in the study and 48 hours later. Laboratory analyses were performed by using immunofluorometric assay for MMP-8 and ELISA for TIMP-1. MMP-8 and TIMP-1 levels were compared between 90-day survivors and nonsurvivors. Survival was compared in quartiles based on TIMP-1 levels, and ROC analysis was performed to calculate areas under the curves. The relationship between MMP-8 and TIMP-1 levels and degree of hypoxemia was examined., Results: The final analyses included 563 patients. Admission TIMP-1 levels were higher in nonsurvivors, median 367 ng/mL (interquartile range 199-562), than survivors, median 240 ng/mL (interquartile range 142-412), WMWodds 1.68 (95% confidence interval [CI], 1.43-2.08). MMP-8 levels may have differed between survivors and nonsurvivors, WMWodds 1.20 (95% CI, 1.01-1.43), but no difference was found in the MMP-8/TIMP-1 molar ratio, WMWodds 0.83 (95% CI, 0.67-1.04). Difference in survival between quartiles based on TIMP-1 was significant (log-rank, P < 0.001). ROC analysis produced an area under the curve 0.63 (95% CI, 0.58-0.69) for TIMP-1. TIMP-1 was associated with severity of hypoxemia. TIMP-1 levels were higher in an ARDS subgroup than in the whole cohort, WMWodds 1.65 (95% CI, 1.15-2.44)., Conclusions: MMP-8 levels were possibly higher in 90-day nonsurvivors but performed poorly in predicting outcome. Increased systemic levels of TIMP-1 were associated with more severe hypoxemia and worse outcome in a large cohort of mechanically ventilated critically ill patients and in a subgroup of ARDS patients.