Anneli Lauhio

Matrix metalloproteinases: Contribution to pathogenesis, diagnosis and treatment of periodontal inflammation

Matrix metalloproteinases (MMPs) form a family of enzymes that mediate multiple functions both in the tissue destruction and immune responses related to periodontal inflammation. The expression and activity of MMPs in non‐inflamed periodontium is low but is drastically enhanced to pathologically elevated levels due to the dental plaque and infection‐induced periodontal inflammation. Soft and hard tissue destruction during periodontitis and peri‐implantitis are thought to reflect a cascade of events involving bacterial virulence factors/enzymes, pro‐inflammatory cytokines, reactive oxygen species and MMPs. However, recent studies suggest that MMPs can also exert anti‐inflammatory effects in defence of the host by processing anti‐inflammatory cytokines and chemokines, as well as by regulating apoptotic and immune responses. MMP‐inhibitor (MMPI)‐drugs, such as doxycycline, can be used as adjunctive medication to augment both the scaling and root planing‐treatment of periodontitis locally and to reduce inflammation systematically. Furthermore, MMPs present in oral fluids (gingival crevicular fluid (GCF), peri‐implant sulcular fluid (PISF), mouth‐rinses and saliva) can be utilized to develop new non‐invasive, chair/bed‐side, point‐of‐care diagnostics for periodontitis and dental peri‐implantitis.

Collagenase-2 (MMP-8) as a point-of-care biomarker in periodontitis and cardiovascular diseases. Therapeutic response to non-antimicrobial properties of tetracyclines

Neutrophil collagenase or collagenase-2 (matrix metalloproteinase [MMP]-8) belongs to the collagenase subgroup of the MMP superfamily of calcium- and zinc-dependent neutral proteinases. MMP-8 is catalytically the most competent proteinase to initiate type I collagen and extracellular matrix degradation associated with periodontal and peri-implant tissue destruction leading to tooth and dental implant loss. Regarding cardiovascular diseases, pathologically excessive MMP-8 has been implicated in atherosclerotic plaque destabilization and rupture probably through its proteolytic ability to thin the protecting collagenous fibrous cap lining coronary and other arteries. During the initiation and course of inflammatory responses in periodontitis, peri-implantitis and cardiovascular diseases, proinflammatory mediators including especially MMP-8 are up-regulated not only in affected tissues but also in the secreted, disease-affected, oral fluids (gingival crevicular fluid [GCF], peri-implant sulcular fluid [PISF], mouthrinse and saliva) as well as in serum and plasma. Regarding periodontitis, peri-implantitis and cardiovascular diseases, the oral fluid and serum MMP-8 analysis has proven to be a sensitive and an objective biomarker as an indicator of health, pathologic processes and pharmacologic response to therapeutic intervention including doxycycline medication as an MMP inhibitor. Oral fluids, i.e., GCF, PISF, mouthrinse and saliva are easily and non-invasively collected for the site- and patient-specific diagnostic analysis in periodontitis and peri-implantitis, whereas serum and/or plasma sample collection is required for diagnosis and monitoring of cardiovascular diseases. Research in periodontology and cardiology has identified a need for the development of innovative point-of-care diagnostic tests for MMP-8. We summarize and review the recent studies on these topics.

In vivo inhibition of human neutrophil collagenase (MMP-8) activity during long-term combination therapy of doxycycline and non-steroidal anti-inflammatory drugs (NSAID) in acute reactive arthritis.

We studied the in vivo effect of long‐term doxycycline treatment combined with NSAID on human interstitial collagenases, other matrix melalloproteinases, serine proteinases, tissue inhibitor of matrix metalloproteinase‐1 (TIMP‐1) and lactoferrin from saliva and serum during the course of acute reactive arthritis (ReA). Collagenase activity and serine proteases (elastase‐like, cathepsin G‐like and trypsin‐like activities) of saliva (n= 10) and gelatinase, lactoferrin and TIMP‐1 of saliva (n=10) and serum (n= 10) samples before and after 2 months doxycycline treatment, combined with NSAID, were studied by quantitative SDS‐PAGE assay, ELISA assay and by spectrophotometric assay. The cellular source and molecular forms of salivary collagenase were characterized by immunoblotting using specific antisera. We found that activities of total and endogenously active interstitial collagenase reduced significantly. The salivary collagenase was found to originate from neutrophils. No fragmentation of either pro 75‐kD and active 65‐kD MMP‐8 was detected after 2 months doxycycline treatment. However, during 2 months doxycycline and NSAID treatment no reduction of salivary and serum gelatinase, lactoferrin and TIMP–1‐levels and salivary serine protease activities were detected. The in vivo inhibition of collagenase (MMP‐8) activity during long‐term doxycycline therapy in human saliva containing inflammatory exudate of ReA patients may contribute to the reduced tissue destruction observed in recent clinical and animal model studies in arthritides during long‐term doxycycline/tetracycline treatment.

Enhanced systemic matrix metalloproteinase response in Helicobacter pylori gastritis.

Background. Helicobacter pylori causes chronic gastritis, peptic ulcer disease, and is the most important risk factor for non-cardia gastric cancer, and has been shown to upregulate matrix metalloproteinases (MMPs) in infected gastric mucosa. MMPs are proteolytic enzymes regulated by tissue inhibitors of metalloproteinases (TIMPs). Aims. We set up this study to find out whether H. pylori gastritis induces systemic MMP response. Methods. Serum samples were collected from patients undergoing gastroscopy; 26 patients had H. pylori gastritis and 18 were H. pylori-negative controls with normal gastric mucosa. Serum MMP levels were analysed by enzyme-linked immunosorbent assay. Results. Significantly elevated serum levels of collagenase-2 (MMP-8), gelatinase B (MMP-9), neutrophil elastase (NE), and myeloperoxidase (MPO), and reduced serum levels of gelatinase A (MMP-2) and TIMP-1 were demonstrated in patients with H. pylori gastritis as compared to H. pylori-negative controls. No significant differences were shown in serum matrilysin-1 (MMP-7) levels. Conclusions. For the first time, we show enhanced MMP-8 response in H. pylori infection together with other neutrophil degranulation products (MMP-9, MPO, NE). Elevated circulating neutrophil degranulation product levels in serum of H. pylori-positive patients reflect accelerated proteolysis and oxidative stress, and may contribute to extraintestinal sequelae, such as cardiovascular diseases.

Reduction of matrix metalloproteinase 8-neutrophil collagenase levels during long-term doxycycline treatment of reactive arthritis.

The aim of this work was to determine whether human polymorphonuclear neutrophilic interstitial collagenase (matrix metalloproteinase 8 [MMP-8]) levels are reduced during long-term doxycycline treatment in humans with reactive arthritis. Serum MMP-8 levels were reduced (mean +/- standard error of the mean, 678.9 +/- 185.6 versus 491.2 +/- 144.8 ng of MMP-8 per ml), but not statistically significantly. However, the reduction of salivary MMP-8 levels was statistically significant (3,729 +/- 1,905.3 versus 1,866 +/- 780.0 ng of MMP-8 per ml, P < 0.05). This study demonstrated that a 2-month regimen of doxycycline can reduce MMP-8 levels in serum and especially in body fluids (i.e., saliva) containing inflammatory exudates and thus may contribute to reduced tissue destruction.

Analysis of systemic and local odontogenic infection complications requiring hospital care

OBJECTIVEnAnalysis of systemic and local odontogenic infection complications requiring hospital care.nnnMETHODSnAll cases of odontogenic infections requiring hospital care, which were adjudicated in the Finnish Patient Insurance Centre during 2000-2003, were analysed. Patient characteristics, and the course and outcome of infection were reviewed.nnnRESULTSnThe study material consisted of 35 patient cases; 15 male, 20 female; mean age 38.4 (16-67) years. The mean length of hospital stay was 14.8 (2-81) days. Nine patients required intensive care for mean 6.2 (2-19) days. Twenty-five (71%) patients developed local infection complications with cellulitis and abscess formation, and 10 (29%) patients a generalised or metastatic infection complication. The length of hospital stay among patients with systemic complications was longer than with local complications, 30.2 (2-81) days vs. 8.0 (2-34) days (p=0.0144). All patients with local complications survived but three of the 10 patients with systemic complications died. Medically compromised patients with underlying disease developed more often systemic infection complications than previously healthy patients (p=0.0028).nnnCONCLUSIONSnMedically compromised patients appear more susceptible to systemic rather than local infection complications with a need for significantly longer hospital stay and with an increased risk for fatal complications.

Is dental treatment of an infected tooth a risk factor for locally invasive spread of infection

PURPOSEnTo determine the impact of antecedent dental procedures and dental health on the course of odontogenic maxillofacial infections requiring hospital care.nnnPATIENTS AND METHODSnIn this retrospective cohort study in a referral center, we evaluated medical records and panoramic radiographs of all patients admitted because of odontogenic maxillofacial infection (n = 84). The predictor variables were preceding dental treatment, antimicrobial therapy, and dental health. The outcome variables comprised infection parameters, length of stay, need for intensive care, and management during hospitalization.nnnRESULTSnThe mean age of the patients was 43.2 ± 16.5 years and 60% were men. Dental procedure preceded the spread of the infection in 49 cases (58%): endodontic treatment (n = 22), tooth extraction (n = 19), and minor first aid (n = 8). Twenty-seven patients had not received any dental or antimicrobial treatment in the recent past. Antimicrobial treatment alone had been given to 8 patients. Patients without preceding treatment had the highest C-reactive protein levels on admission and at maximum (P = .020 and P = .011) and the highest white blood cell counts on admission (P = .011). Their length of stay was also longer, and they needed intensive care more often than the other patients. Maximum C-reactive protein levels and white blood cell counts between treatment groups did not significantly differ from each other.nnnCONCLUSIONSnThe systemic response to the infection was strongest and the course of the infection most severe in the absence of preceding dental treatment and in patients with poor dental health. All types of dental treatment contributed to a less severe course of infection.

Patient-reported complications associated with Campylobacter jejuni infection

This study aimed to investigate the occurrence of complications, especially musculoskeletal symptoms, after sporadic Campylobacter jejuni enteritis of domestic origin in Finland. This multi-centre cross-sectional study was conducted during a seasonal peak in 2002. Questionnaires were sent to Campylobacter-positive patients, representing different geographical areas, 2 months after collection of positive stool samples. Medical records were viewed in several cases. Besides antimicrobial susceptibility testing C. jejuni isolates were serotyped. A total of 235 patients (58%) returned the questionnaire and 201 C. jejuni-positive patients were finally included in the study. Musculoskeletal symptoms associated with C. jejuni enteritis were frequent (39%); joint pain was most commonly reported (81%). The incidence of reactive arthritis was 4% and that of Achilles enthesopathy and/or heel pain was 9%. Stomach ache during enteritis was associated with the later development of joint pain. Antimicrobial treatment was common but did not prevent complications.

Changing clinical features of odontogenic maxillofacial infections

Odontogenic maxillofacial infections occasionally require hospital care. Our aim was to study whether the number and the clinical features of patients hospitalized due to odontogenic abscesses in a large hospital district in Finland had changed in one decade. A retrospective analysis of two 12-month study cohorts one decade apart from the same population base was conducted. The first cohort comprised 71 patients and the second cohort comprised 101 patients. The incidence of odontogenic infections requiring hospital care increased from 5.3 to 7.2 per 100,000 inhabitants. The need for intensive care increased significantly from 15% to 32%, and the maximal C-reactive protein levels were significantly higher in the latter cohort, 127xa0mg/L, compared to the first cohort, 104xa0mg/L. The proportion of previously healthy patients decreased significantly from 83% to 65%. Odontogenic maxillofacial infections have become more prevalent and more severe during the decade in our hospital district. An increasing proportion of patients had underlying diseases.

Potentiative effects of neutral proteinases in an inflamed lung: relationship of neutrophil procollagenase (proMMP-8) to plasmin, cathepsin G and tryptase in bronchiectasis in vivo

We attempted to study the possible relationships between neutrophil-type procollagenase/pro-matrix metalloproteinase (MMP-8) and the serine proteinases plasmin, cathepsin G and tryptase in bronchiectasis. The presence of the plasmin/plasminogen system and plasmin-, cathepsin G- and tryptase-like activities were compared to the activity of endogenously activated MMP-8 in bronchoalveolar lavage (BAL) fluid in 38 bronchiectasis patients and in 14 healthy controls by means of immunohistochemistry, Western-blot and substrate-based functional assays. In contrast to cathepsin G- and tryptase-like activities, the plasmin/plasminogen activator system in BAL fluid was observed to have a relatively weak activation stage and no correlation with disease severity. Neither plasmin-like activities nor concentrations of plasminogen activators from the bronchiectatic patients differed significantly from the values of healthy controls. Immunolocation of plasminogen activator inhibitor-1 showed a marked, but not significant, increase in bronchiectatic lung as compared to controls. In contrast to cathepsin G- and tryptase-like activities, with their strong and significant correlation with endogenously activated collagenase (r=0.9; p=0.0001; and r=0.6; p=0.03, respectively), no correlations were observed between plasmin-like and endogenously activated collagenase (r=0.3; p=0.2) in bronchiectasis. These findings suggest that cathepsin G- and tryptase-like activities may act as potent pro-matrix metalloproteinase-8 activators in patients with bronchiectasis, whereas the plasminogen activator/plasmin cascade was shown to be down-regulated.