Mervi Gürsoy

Analysis of matrix metalloproteinases, especially MMP-8, in gingival creviclular fluid, mouthrinse and saliva for monitoring periodontal diseases.

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.

Periodontal Status and Neutrophilic Enzyme Levels in Gingival Crevicular Fluid During Pregnancy and Postpartum

BACKGROUND Pregnancy induces or enhances susceptibility to gingivitis; however, the presence and role of neutrophilic enzymes in pregnancy-related gingivitis are not well known. The present study demonstrates the relationship between neutrophilic enzymes in gingival crevicular fluid (GCF) and periodontal status during pregnancy and postpartum. METHODS At baseline, 30 periodontally healthy pregnant women (Pr group) and 24 non-pregnant women (N-Pr group) as their controls participated in the study. The Pr group was examined once per each trimester and twice during postpartum and the N-Pr group three times (on successive months). During each visit, GCF samples were collected from all first molars, and clinical measurements (visible plaque index, bleeding on probing [BOP], probing depth [PD], and clinical attachment level) were recorded. The samples were analyzed for matrix metalloproteinase (MMP)-8, polymorphonuclear neutrophil (PMN) elastase, myeloperoxidase (MPO), and tissue inhibitor of matrix metalloproteinase (TIMP)-1. Their levels were compared to the periodontal status at the collection site. RESULTS In the Pr group, BOP and PD scores significantly increased between the first and second trimester, indicating pregnancy gingivitis. This increased inflammation was not reflected by the enzymes examined in GCF; the amounts of PMN elastase decreased continuously during the follow-up period, and those of MPO and MMP-8 did not increase until delivery, whereas TIMP-1 amounts remained stable throughout the follow-up period. In the N-Pr group, all parameters remained steady. CONCLUSION Despite an increased susceptibility to gingivitis during mid-pregnancy, the host response does not seem to activate its own degradative enzymes.

High Salivary Estrogen and Risk of Developing Pregnancy Gingivitis

BACKGROUND Estrogen regulates the cellular functions of several tissues that may disturb the host response against bacteria. The present aim is to evaluate the contribution of estrogen to the severity of gingival inflammation during pregnancy. METHODS Salivary estrogen levels from 30 pregnant and 24 non-pregnant females were related to their periodontal health parameters, including visible plaque index (VPI) and bleeding on probing (BOP) from six sites per tooth. The pregnant group was examined three times during pregnancy and twice during postpartum, and the non-pregnant group was examined three times, once per subsequent month. RESULTS Salivary estrogen levels increased significantly during the second (P <0.01) and third (P <0.05) trimesters. In both participant groups, BOP scores correlated significantly with VPI scores (r = 0.498 to 0.870) but not with estrogen levels. In all trimesters and postpartum, the individuals with both high estrogen and high VPI levels had the highest frequency of pregnancy gingivitis. During the second and third trimesters, simultaneously enhanced estrogen levels and VPI scores brought an additional risk of developing gingivitis compared with a high VPI score alone. CONCLUSION The present findings suggest that, during pregnancy, the estrogen level determines the magnitude of gingival inflammation developed against microbial plaque at the gingival margin.

MMPREDOX/NO Interplay in Periodontitis and Its Inhibition with Satureja hortensis L. Essential Oil

Satureja hortensis L. is an aromatic plant with antibacterial and antibiofilm activities against periodontopathogens. Here, we attempted to find out whether the antioxidant properties of S. hortensis L. essential oil (EO) could be used to inhibit matrix metalloproteinase (MMP) activities and prevent the induction of cell death by a pro‐oxidant insult. First, a landscape analysis of MMP and REDOX/nitric oxide (NO)‐related genes was performed (MRN model), and array data from periodontitis patients were plotted over the newly developed model. Thereafter, the antigelatinolytic activity of S. hortensis L. EO and its preventive effect against hydrogen peroxide (H2O2)‐induced cell death were tested in vitro (HaCaT cells). Up‐regulation of MMP genes in the MRN network (except for MMP‐10, ‐15, ‐16, ‐20, ‐25, and ‐26) and differential expression of genes coding for antioxidant enzymes were found among others in periodontitis samples. MMP2 and MMP9 were central genes in the MRN network model. Moreover, treatments with 1 and 5 μl/ml of S. hortensis L. EO inhibited both MMP‐2 and MMP‐9 activities, and H2O2‐induced cell death in vitro. We concluded that S. hortensis L. EO could be a promising host‐modulating agent, since oxidative stress and excessive MMP expression/activity are typical hallmarks of periodontal pathogenesis.

Bioinformatical and in vitro approaches to essential oil-induced matrix metalloproteinase inhibition

Context: Essential oils carry diverse antimicrobial and anti-enzymatic properties. Objective: Matrix metalloproteinase (MMP) inhibition characteristics of Salvia fruticosa Miller (Labiatae), Myrtus communis Linnaeus (Myrtaceae), Juniperus communis Linnaeus (Cupressaceae), and Lavandula stoechas Linnaeus (Labiatae) essential oils were evaluated. Materials and methods: Chemical compositions of the essential oils were analyzed by gas chromatography–mass spectrometry (GC–MS). Bioinformatical database analysis was performed by STRING 9.0 and STITCH 2.0 databases, and ViaComplex software. Antibacterial activity of essential oils against periodontopathogens was tested by the disc diffusion assay and the agar dilution method. Cellular proliferation and cytotoxicity were determined by commercial kits. MMP-2 and MMP-9 activities were measured by zymography. Results: Bioinformatical database analyses, under a score of 0.4 (medium) and a prior correction of 0.0, gave rise to a model of protein (MMPs and tissue inhibitors of metalloproteinases) vs. chemical (essential oil components) interaction network; where MMPs and essential oil components interconnected through interaction with hydroxyl radicals, molecular oxygen, and hydrogen peroxide. Components from L. stoechas potentially displayed a higher grade of interaction with MMP-2 and -9. Although antibacterial and growth inhibitory effects of essential oils on the tested periodontopathogens were limited, all of them inhibited MMP-2 in vitro at concentrations of 1 and 5 µL/mL. Moreover, same concentrations of M. communis and L. stoechas also inhibited MMP-9. MMP-inhibiting concentrations of essential oils were not cytotoxic against keratinocytes. Discussion and conclusion: We propose essential oils of being useful therapeutic agents as MMP inhibitors through a mechanism possibly based on their antioxidant potential.

A Systems Biology Approach to Reveal Putative Host-Derived Biomarkers of Periodontitis by Network Topology Characterization of MMP-REDOX/NO and Apoptosis Integrated Pathways.

Periodontitis, a formidable global health burden, is a common chronic disease that destroys tooth-supporting tissues. Biomarkers of the early phase of this progressive disease are of utmost importance for global health. In this context, saliva represents a non-invasive biosample. By using systems biology tools, we aimed to (1) identify an integrated interactome between matrix metalloproteinase (MMP)-REDOX/nitric oxide (NO) and apoptosis upstream pathways of periodontal inflammation, and (2) characterize the attendant topological network properties to uncover putative biomarkers to be tested in saliva from patients with periodontitis. Hence, we first generated a protein-protein network model of interactions (“BIOMARK” interactome) by using the STRING 10 database, a search tool for the retrieval of interacting genes/proteins, with “Experiments” and “Databases” as input options and a confidence score of 0.400. Second, we determined the centrality values (closeness, stress, degree or connectivity, and betweenness) for the “BIOMARK” members by using the Cytoscape software. We found Ubiquitin C (UBC), Jun proto-oncogene (JUN), and matrix metalloproteinase-14 (MMP14) as the most central hub- and non-hub-bottlenecks among the 211 genes/proteins of the whole interactome. We conclude that UBC, JUN, and MMP14 are likely an optimal candidate group of host-derived biomarkers, in combination with oral pathogenic bacteria-derived proteins, for detecting periodontitis at its early phase by using salivary samples from patients. These findings therefore have broader relevance for systems medicine in global health as well.

Salivary interleukin-17 and tumor necrosis factor-α in relation to periodontitis and glycemic status in type 2 diabetes mellitus

Poorly‐controlled glycemic status in type 2 diabetes mellitus (T2DM) is suggested to play a role in the periodontal inflammatory process by aggregating the local cytokine response. Our objectives were to profile salivary interleukin (IL)‐17 and tumor necrosis factor (TNF)‐α levels in subjects with T2DM and to examine their relevance for the periodontal health status and glycemic control levels.

Does estradiol have an impact on the dipeptidyl peptidase IV enzyme activity of the Prevotella intermedia group bacteria

Initiation and development of pregnancy-associated gingivitis is seemingly related to the microbial shift towards specific gram-negative anaerobes in subgingival biofilms. It is known that Prevotella intermedia sensu lato is able to use estradiol as an alternative source of growth instead of vitamin K. The aim of the present study was to investigate the impact of estradiol on the bacterial dipeptidyl peptidase IV (DPPIV) enzyme activity in vitro as a virulent factor of the Prevotella intermedia group bacteria, namely P. intermedia, Prevotella nigrescens, Prevotella pallens, and Prevotella aurantiaca. In all experiments, 2 strains of each Prevotella species were used. Bacteria were incubated with the concentrations of 0, 30, 90, and 120 nmol/L of estradiol and were allowed to build biofilms at an air-solid interface. DPPIV activities of biofilms were measured kinetically during 20 min using a fluorometric assay. The enzyme activity was later related to the amount of protein produced by the same biofilm, reflecting the biofilm mass. Estradiol significantly increased DPPIV activities of the 8 Prevotella strains in a strain- and dose-dependent manner. In conclusion, our in vitro experiments indicate that estradiol regulates the DPPIV enzyme activity of P. intermedia, P. nigrescens, P. pallens, and P. aurantiaca strains differently. Our results may, at least partly, explain the role of estradiol to elicit a virulent state which contributes to the pathogenesis of pregnancy-related gingivitis.

Salivary cytokine levels in early gingival inflammation

ABSTRACT Salivary protein levels have been studied in periodontitis. However, there is lack of information on salivary cytokine levels in early gingival inflammation. The aim of this study was to determine salivary levels of vascular endothelial growth factor (VEGF), interleukin (IL)-8, monocyte chemoattractant protein (MCP)-1, IL-1β, and IL-1 receptor antagonist (IL-1Ra) in gingival inflammation. Twenty-eight systemically and orally healthy nonsmokers abstained from oral hygiene protocols for 10 days. After that, self-performed cleaning was resumed for 14 days. Plaque and gingival indexes were measured, and saliva samples were collected at days 1, 4, 7, 10, and 24. Salivary cytokines were detected with Luminex®-xMAP™. Salivary IL-1β, IL-1Ra, and VEGF levels decreased after 10 days’ development of experimental gingivitis and reached baseline levels at the end of the 2-week resolution period. Salivary IL-8 levels decreased and remained low during development and resolution of experimental gingivitis. Initial inflammation in gingival tissues is associated with a decrease in inflammatory cytokines in saliva. Further studies are needed to evaluate if inflammatory cytokines bind to their functional receptors within the gingival tissue during early gingivitis, which may limits their spillover to the gingival crevice and ultimately saliva.

Salivary antimicrobial defensins in pregnancy.

AIM Susceptibility to and severity of gingival inflammation are enhanced during pregnancy; however, regulation of oral innate immune response, including antimicrobial peptides, during pregnancy is still unknown. We analysed salivary levels of human beta-defensin (hBD)-1, -2, -3, and human neutrophil peptide (HNP)-1 in pregnant women, and related those to their periodontal status. MATERIAL AND METHODS In this cohort study, 30 generally healthy, non-smoking Caucasian women without periodontitis were followed at three time points during pregnancy and twice post-partum. The non-pregnant group consisted of 24 women, who were examined three times at the following months. At each visit, periodontal status was recorded and stimulated saliva samples were collected. Salivary estradiol, progesterone, and defensin concentrations were measured by ELISA assays. RESULTS After adjusting for visible plaque and gingival bleeding, reduced salivary concentrations of hBD-1, hBD-2, and HNP-1 were found especially during the third trimester, whereas hBD-3 concentrations did not change during pregnancy and post-partum visits. Weak associations were observed between salivary defensin and hormone concentrations and clinical parameters. CONCLUSION There seems to be an independent regulation cascade for each antimicrobial defensin in the oral cavity during pregnancy, despite of the similarities between these antimicrobial peptides.