Salivary levels of matrix metalloproteinase (MMP)-9 and tissue inhibitor of matrix metalloproteinase (TIMP)-1: A pilot study about the relationship with periodontal status and MMP-9−1562C/T gene promoter polymorphism

Salivary concentrations of secretory leukocyte protease inhibitor and matrix metallopeptidase-9 following a single bout of exercise are associated with intensity and hydration status

AIM

To investigate the effects of exercise on salivary concentrations of inflammatory markers by analyzing a panel of 25 inflammatory markers in subjects who had participated in bicycle ergometer tests varying in workload and hydration status.

METHODS

Fifteen healthy young men (20-35 years) had performed 4 different exercise protocols of 1 hour duration in a randomly assigned cross-over design, preceded by a rest protocol. Individual workloads depended on participant's pre-assessed individual maximum workload (Wmax): rest (protocol 1), 70% Wmax in hydrated (protocol 2) and dehydrated (protocol 3) state, 50% Wmax (protocol 4) and intermittent 85%/55% Wmax in 2 min blocks (protocol 5). Saliva samples were collected before (T0) and immediately after exercise (T1), and at several time points after exercise (2 hours (T3), 3 hours (T4), 6 hours (T5) and 24 hours (T6)). Secretory Leukocyte Protease Inhibitor (SLPI), Matrix Metallopeptidase-9 (MMP-9) and lactoferrin was analyzed using a commercial ELISA kit, a panel of 22 cytokines and chemokines were analyzed using a commercial multiplex immunoassay. Data was analyzed using a multilevel mixed linear model, with multiple test correction.

RESULTS

Among a panel of 25 inflammatory markers, SLPI concentrations were significantly elevated immediately after exercise in all protocols compared to rest and higher concentrations reflected the intensity of exercise and hydration status. MMP-9 showed a significant increase in the 70% Wmax dehydrated, 50% Wmax and intermittent protocols.

CONCLUSIONS

Salivary concentrations of SLPI and MMP-9 seem associated with exercise intensity and hydration status and may offer non-invasive biomarkers to study (local) inflammatory responses to different exercise intensities in human studies.

Matrix metalloproteinase-9-1562 C/T promoter gene polymorphism in chronic periodontitis: A cross-sectional observational study

Background:

Matrix metalloproteinases (MMPs) are a major group of enzymes, released in inflamed periodontal tissues in large quantities, resulting in connective tissue matrix breakdown. One of the most predominant MMPs is MMP-9. Association between chronic periodontitis (CP) and MMP-9 gene polymorphism (GP) in some ethnic populations has been already established. The aim of the current study was to assess the association of single-nucleotide polymorphism in the promoter region of MMP-9 gene with CP in Kolkata population, if any.

Materials and Methods:

Forty eligible individuals were recruited for the study and grouped as A and B: Group A (twenty periodontally healthy individuals) and Group B (twenty CP patients). Venous blood samples collected from all the forty individuals were used to isolate the genomic DNA. GP for MMP-9 gene was detected using polymerase chain reaction and sequencing method. The data obtained were then analyzed statistically.

Results:

A significantly different genotypic and allelic variation was observed in the control and test groups, with C/T genotype and T allele present in only CP group.

Conclusion:

Within the limitations of this study, we can conclude that there was no significant association between patients with periodontitis and MMP-9-1562 C/T promoter GP.

Changes in salivary matrix metalloproteinase-3, -8, and -9 concentrations after 6 weeks of non-surgical periodontal therapy

Background

Studies using salivary inflammatory biomarkers for diagnosing and monitoring the progression of periodontal disease have garnered increased attention in recent years. The present study aimed to identify changes in clinical parameters and concentrations of salivary matrix metalloproteinases (MMPs) following 6 weeks of non-surgical periodontal therapy (NSPT).

Methods

A 6-week NSPT program was applied to 51 adults aged ≥ 20 years. The program involved scaling, root planing, and professional toothbrushing for healthy participants and those with periodontal disease. Patients with periodontal disease underwent professional toothbrushing during all three visits. Periodontal pocket depth (PD) and gingival bleeding were assessed at week 0, week 3, and week 6, and saliva samples were collected to measure the concentrations of MMP-3, -8, and -9.

Results

All clinical parameters were improved in the periodontal disease groups following the NSPT course. Compared with healthy participants, the patients with periodontal disease showed increased concentrations of salivary MMP-3, -8, and -9. During the 6-week program, patients with periodontal disease also showed significant reductions in PD and gingival bleeding during the third week; no significant reduction was found during the sixth week. Significant reductions in the concentrations of salivary MMP-3, -8, and -9 were also noted in the periodontal disease group at week 3. The sensitivity and specificity of MMP-3 for predicting periodontitis were 81.8% and 55.5%, respectively.

Conclusion

The present study found that NSPT resulted in reductions of salivary MMP-3, -8, and -9, and identified the potential of MMP-3 as a biomarker in the diagnosis of periodontal disease. These findings may serve as foundational data for future studies into the development of diagnostic kits for periodontal disease.

Is TIMP-1 a biomarker for periodontal disease? A systematic review and meta-analysis

Objective

One of the most important families of proteases associated with periodontal disease is the family of the matrix metalloproteinases (MMPs). Their activity is regulated by tissue inhibitors of metalloproteinases (TIMPs), and an imbalance between MMP activity and regulation by TIMPs has been associated with the progression of periodontal disease. This strong interaction between TIMPs and MMPs might be an indication that TIMPs can be used as a biomarker to monitor periodontal disease progression in oral fluids. In particular, TIMP‐1 is a frequently studied biomarker for periodontal diseases. Therefore, the aim of this systematic review was to evaluate the scientific literature regarding TIMP‐1 concentrations in oral fluids of patients suffering from periodontitis or gingivitis in comparison to healthy individuals.

Material and Methods

PubMed/ MedLine and Web of Science databases were searched electronically. Studies that met the inclusion criteria were systematically evaluated and assessed for eligibility and risk of bias. Meta‐analysis was performed through the random effects model to assess the association between periodontitis/gingivitis and TIMP‐1 concentration in stimulated saliva, unstimulated saliva, and gingival crevicular fluid (GCF).

Results

The search strategy provided a total of 322 studies of which 10 studies met all inclusion criteria. Two studies investigated TIMP‐1 concentrations in GCF, three studies in unstimulated saliva, and five studies investigated TIMP‐1 concentrations in stimulated saliva. Three studies revealed that TIMP‐1 levels in oral fluids were significantly decreased in periodontal disease. Meta‐analysis revealed that there is no statistically significant difference between TIMP‐1 concentration in oral fluids of periodontitis/gingivitis patients in comparison to healthy individuals.

Conclusions

This systematic review with meta‐analysis shows that periodontal diseases are not associated with a statistically significant change in TIMP‐1 concentration in oral fluids.

SP, N. M, Barik AK, Pai KM, Unnikrishnan VK, George SD, Kartha VB, Chidangil S. Photonics of human saliva: potential optical methods for the screening of abnormal health conditions and infections

Human saliva can be treated as a pool of biological markers able to reflect on the state of personal health. Recent years have witnessed an increase in the use of optical devices for the analysis of body fluids. Several groups have carried out studies investigating the potential of saliva as a non-invasive and reliable clinical specimen for use in medical diagnostics. This brief review aims to highlight the optical technologies, mainly surface plasmon resonance (SPR), Raman, and Fourier transform infrared (FTIR) spectroscopy, which are being used for the probing of saliva for diverse biomedical applications. Advances in bio photonics offer the promise of unambiguous, objective and fast detection of abnormal health conditions and viral infections (such as COVID-19) from the analysis of saliva.

The Association of Matrix Metalloproteinase Gene Polymorphisms and Periodontitis: An Overview

Periodontitis is a multifactorial inflammatory disease, pathogenic bacteria being the primary etiological agents. The host response and the severity of clinical manifestation are determined by genetic and environmental factors. There is some evidence that the individual response to environmental variations in the immune response in periodontitis is associated with genetic factors. Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes located in the extracellular matrix. Their primary function is the breakdown of connective tissue components. Their role in the oral cavity is very vital. In this literature review, we summarized the contemporary knowledge on the function of MMPs in oral cavity and periodontal disease.

Salivary Biomarkers and Their Application in the Diagnosis and Monitoring of the Most Common Oral Pathologies

Saliva is a highly versatile biological fluid that is easy to gather in a non-invasive manner—and the results of its analysis complement clinical and histopathological findings in the diagnosis of multiple diseases. The objective of this review was to offer an update on the contribution of salivary biomarkers to the diagnosis and prognosis of diseases of the oral cavity, including oral lichen planus, periodontitis, Sjögren’s syndrome, oral leukoplakia, peri-implantitis, and medication-related osteonecrosis of the jaw. Salivary biomarkers such as interleukins, growth factors, enzymes, and other biomolecules have proven useful in the diagnosis and follow-up of these diseases, facilitating the early evaluation of malignization risk and the monitoring of disease progression and response to treatment. However, further studies are required to identify new biomarkers and verify their reported role in the diagnosis and/or prognosis of oral diseases.

Mucin 4 and matrix metalloproteinase 7 as novel salivary biomarkers for periodontitis

AIM

Periodontitis is a chronic inflammatory disease, characterized by irreversible destruction of tooth-supporting tissue including alveolar bone. We recently reported mucin 4 (MUC4) and matrix metalloproteinase 7 (MMP7) as highly associated with periodontitis in gingival tissue biopsies. The aim of this study was to further investigate the levels of MUC4 and MMP7 in saliva and gingival crevicular fluid (GCF) samples of patients with periodontitis.

MATERIALS AND METHODS

Saliva and GCF samples were collected from periodontitis patients and healthy controls. The levels of MUC4, MMP7, and total protein concentrations were analysed using ELISA or Bradford assay.

RESULTS

MUC4 levels were significantly lower in saliva and GCF from periodontitis patients relative to healthy controls. MMP7 levels were significantly higher in saliva and GCF from periodontitis patients. Multivariate analysis revealed that MUC4 was significantly associated with periodontitis after adjusting for age and smoking habits and, moreover, that the combination of MUC4 and MMP7 accurately discriminated periodontitis from healthy controls.

CONCLUSIONS

MUC4 and MMP7 may be utilized as possible novel biomarkers for periodontitis.

A meta-analysis of MMP-9 promoter -1562 C/T polymorphism on susceptibility of chronic periodontitis

Background

Although many studies have focused on the association of the MMP-9 promoter −1562 C/T polymorphism with the susceptibility and/or severity of chronic periodontitis (CP), results have been inconsistent. Therefore, a meta-analysis of all eligible studies was performed to derive a more precise estimation of the association between this polymorphism and CP risk.

Methods

All relevant studies were identified through a database search in PubMed, Medline, and Web of Science. All the full-text studies with appropriate analytical design, published in English, which evaluated the association of MMP-9 promoter −1562C/T polymorphism with CP risk using validated genotyping methods, and with non-duplicated data were selected for this study. A fixed-effect model was used to calculate pooled ORs in the absence of heterogeneity across included trials (P > 0.1 and I² < 50 %), otherwise the random-effect model was applied.

Results

In an overall meta-analysis, pooled ORs revealed that T variant in the MMP-9 promoter −1562 C/T polymorphism was associated with a significantly decreased risk for CP under all comparison models. In subgroup analyses by ethnicity, pooled ORs showed that a significant association of the MMP-9 promoter −1562 C/T polymorphism with CP risk was only detected in Caucasians and Asians but not in mixed population. In the subgroup analysis by severity of CP, pooled ORs indicated that T allele of the MMP-9 promoter −1562 C/T polymorphism was associated with decreased susceptibility to severe CP while there was no significant association between this polymorphism and moderate CP.

Conclusions

Our meta-analysis showed that T allele in the MMP-9 promoter −1562 C/T polymorphism might be a protective factor for CP, especially in Caucasians and Asians. Moreover, there was a significant association of the MMP-9 promoter −1562 C/T polymorphism with decreased susceptibility to severe CP, while the allelic and/or genotype distributions of this polymorphism were not associated with moderate CP.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-016-2135-3) contains supplementary material, which is available to authorized users.

Matrix metalloproteinase gene polymorphisms and periodontitis susceptibility: a meta-analysis involving 6,162 individuals

We aimed to systematically investigate the potential association of matrix metalloproteinase (MMP)-9, -3, -2, and -8 gene polymorphisms with susceptibility to periodontitis using meta-analysis. A literature search in PubMed, Embase, and Web of Sciencewas conducted to obtain relevant publications. Finally a total of 16 articles with 24 case-control studies (nine on MMP-9-1562 C/T, seven on MMP-3-1171 A5/A6, four on MMP-2-753C/T, and four on MMP-8-799 C/T) were considered in this meta-analysis. The results based on 2,724 periodontitis patients and 3,438 controls showed that MMP-9-1562C/T, MMP-3-1171 A5/A6, and MMP-8-799C/T polymorphisms were associated with periodontitis susceptibility. No significant association was found between MMP-2-753 C/T and periodontitis susceptibility. Subgroup analyses suggested that the MMP-9-1562 C/T polymorphism reduced chronic periodontitis susceptibility and MMP-3-1171 A5/A6polymorphism increased chronic periodontitis susceptibility. In summary, current evidence demonstrated that MMP-9-753 C/Tpolymorphism reduced the risk of periodontitis, MMP-3-1171 5A/6A and MMP-8-799 C/Tpolymorphisms increased the risk of periodontitis, and MMP-2-753 C/T was not associated with risk of periodontitis.

Association of Common Variants in MMPs with Periodontitis Risk

Background. Matrix metalloproteinases (MMPs) are considered to play an important role during tissue remodeling and extracellular matrix degradation. And functional polymorphisms in MMPs genes have been reported to be associated with the increased risk of periodontitis. Recently, many studies have investigated the association between MMPs polymorphisms and periodontitis risk. However, the results remain inconclusive. In order to quantify the influence of MMPs polymorphisms on the susceptibility to periodontitis, we performed a meta-analysis and systematic review. Results. Overall, this comprehensive meta-analysis included a total of 17 related studies, including 2399 cases and 2002 healthy control subjects. Our results revealed that although studies of the association between MMP-8 −799 C/T variant and the susceptibility to periodontitis have not yielded consistent results, MMP-1 (−1607 1G/2G, −519 A/G, and −422 A/T), MMP-2 (−1575 G/A, −1306 C/T, −790 T/G, and −735 C/T), MMP-3 (−1171 5A/6A), MMP-8 (−381 A/G and +17 C/G), MMP-9 (−1562 C/T and +279 R/Q), and MMP-12 (−357 Asn/Ser), as well as MMP-13 (−77 A/G, 11A/12A) SNPs are not related to periodontitis risk. Conclusions. No association of these common MMPs variants with the susceptibility to periodontitis was found; however, further larger-scale and multiethnic genetic studies on this topic are expected to be conducted to validate our results.

Development of a label-free SPR sensor for detection of matrixmetalloproteinase-9 by antibody immobilization on carboxymethyldextran chip

Surface plasmon resonance (SPR) immunosensor has been widely utilized for monitoring antigen-antibody interactions. The sensor measures changes of refractive index upon binding of analyte molecules to specific ligand immobilized on the sensor chip. This effort reports development of SPR immunosensor for real-time and label-free detection of recombinant human matrix metalloproteinases-9 (MMP-9), which has been associated with malignant tumor progression and metastasis by matrix degradation. MMP-9 was expressed in Escherichia coli BL21 and purified by Ni-NTA agarose column. CMD 50 D was activated by EDC/NHS for immobilization of monoclonal anti-MMP-9. Atomic force microscopy images showed uniform distribution of anti-MMP-9 over the sensor chip. Equilibrium constant (KD), maximum binding capacity (Rmax) and ∆Gb values for interaction of MMP-9 and anti-MMP-9 were 0.4nM, 680 µRIU and -53.51kJ/mol, respectively. Concentration of MMP-9 in saliva samples was determined, with linearity in the range of 10-200ng/mL. The limit of detection was found to be 8pg/mL, being lower than most of the previously reported techniques.

Host response mechanisms in periodontal diseases

Periodontal diseases usually refer to common inflammatory disorders known as gingivitis and periodontitis, which are caused by a pathogenic microbiota in the subgingival biofilm, including Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola that trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth, and eventually in tissue, bone and finally, tooth loss. The innate immune response constitutes a homeostatic system, which is the first line of defense, and is able to recognize invading microorganisms as non-self, triggering immune responses to eliminate them. In addition to the innate immunity, adaptive immunity cells and characteristic cytokines have been described as important players in the periodontal disease pathogenesis scenario, with a special attention to CD4⁺ T-cells (T-helper cells). Interestingly, the T cell-mediated adaptive immunity development is highly dependent on innate immunity-associated antigen presenting cells, which after antigen capture undergo into a maturation process and migrate towards the lymph nodes, where they produce distinct patterns of cytokines that will contribute to the subsequent polarization and activation of specific T CD4+ lymphocytes. Skeletal homeostasis depends on a dynamic balance between the activities of the bone-forming osteoblasts (OBLs) and bone-resorbing osteoclasts (OCLs). This balance is tightly controlled by various regulatory systems, such as the endocrine system, and is influenced by the immune system, an osteoimmunological regulation depending on lymphocyte- and macrophage-derived cytokines. All these cytokines and inflammatory mediators are capable of acting alone or in concert, to stimulate periodontal breakdown and collagen destruction via tissue-derived matrix metalloproteinases, a characterization of the progression of periodontitis as a stage that presents a significantly host immune and inflammatory response to the microbial challenge that determine of susceptibility to develop the destructive/progressive periodontitis under the influence of multiple behavioral, environmental and genetic factors.

Salivary biomarkers in a biofilm overgrowth model

BACKGROUND

The purpose of this study is to determine whether baseline salivary inflammatory biomarkers could discriminate between different clinical levels of disease and/or detect clinical changes over a 3-week stent-induced biofilm overgrowth (SIBO) period.

METHODS

A total of 168 participants were enrolled in a 21-day experimental gingivitis investigation and grouped according to clinical measures of periodontal status of health and diseased individuals representing each of five biofilm gingival interface (BGI) periodontal groups: 1) health, all probing depth (PD) <3 mm and bleeding on probing (BOP) <10%; 2) gingivitis, all PD <3 mm and BOP ≥10%; 3) periodontitis (P)1, ≥1 site with PD >3 mm and BOP ≤10%; 4) P2, ≥1 site with PD >3 mm and BOP >10% but ≤50%; and 5) P3, ≥1 site with PD >3 mm and BOP >50%. Stents were used to prevent plaque removal during brushing over one maxillary and one mandibular posterior dental sextant for 21 days. Clinical periodontal parameters and unstimulated saliva were collected at screening, baseline, and each week during SIBO. Saliva samples were assessed for levels of 13 different biomarkers by multiplex immunoassay.

RESULTS

Higher salivary levels of interleukin (IL)-1β, matrix metalloproteinase (MMP)-3, MMP-8, MMP-9, and neutrophil gelatinase-associated lipocalin (NGAL) were found in diseased groups compared with the healthy group at baseline. Conversely, higher IL-1 receptor antagonist (ra) levels were found in healthy patients at baseline. In addition, during SIBO, MMP-1, tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 levels increased across all participant groups. A stepwise linear regression model using all salivary biomarkers demonstrated that, at baseline, increased IL-1ra (P = 0.004) and IL-6 (P = 0.009) were significantly associated with change in PDs during SIBO.

CONCLUSIONS

In summary, this investigation supports salivary levels of IL-1ra and IL-6 as potential indicators for PD changes during induced gingival inflammation. In addition, participants from the BGI-P3 group (severe periodontitis) demonstrated elevated baseline levels of IL-1β, MMP-3, MMP-8, MMP-9, and NGAL compared with the other study groups, strengthening the relevance of participants' biologic phenotype on expression of salivary biomarkers.

Point-of-care diagnosis of periodontitis using saliva: technically feasible but still a challenge

Periodontitis is a chronic inflammation of the periodontium caused by persistent bacterial infection that leads to the breakdown of connective tissue and bone. Because the ability to reconstruct the periodontium is limited after alveolar bone loss, early diagnosis and intervention should be the primary goals of periodontal treatment. However, periodontitis often progresses without noticeable symptoms, and many patients do not seek professional dental care until the periodontal destruction progresses to the point of no return. Furthermore, the current diagnosis of periodontitis depends on time-consuming clinical measurements. Therefore, there is an unmet need for near-patient testing to diagnose periodontitis. Saliva is an optimal biological fluid to serve as a near-patient diagnostic tool for periodontitis. Recent developments in point-of-care (POC) testing indicate that a diagnostic test for periodontitis using saliva is now technically feasible. A number of promising salivary biomarkers associated with periodontitis have been reported. A panel of optimal biomarkers must be carefully selected based on the pathogenesis of periodontitis. The biggest hurdle for the POC diagnosis of periodontitis using saliva may be the process of validation in a large, diverse patient population. Therefore, we propose the organization of an International Consortium for Biomarkers of Periodontitis, which will gather efforts to identify, select, and validate salivary biomarkers for the diagnosis of periodontitis.

Prognostic Value of 8-Hydroxy-2'-Deoxyguanosine and Human Neutrophil Elastase/α1-Proteinase Inhibitor Complex as Salivary Biomarkers of Oxidative Stress in Chronic Periodontitis

BACKGROUND

8-Hydroxy-2'-deoxyguanosine (8-OHdG) and human neutrophil elastase/α1-proteinase inhibitor (HNE/α1-PI) complex have been regarded as reliable biomarkers of oxidative stress in inflammatory conditions. This study investigates whether the salivary levels of these two analytes may be linked with periodontal health status.

METHODS

One hundred ten patients with chronic periodontitis (CP) and 50 healthy controls were selected. Periodontal status was assessed by criteria based on probing depth, clinical attachment level, and extent and severity of periodontal breakdown. 8-OHdG and HNE/α1-PI salivary levels were analyzed by enzyme-linked immunosorbent assay. The association of these analytes with CP was analyzed individually and adjusted for confounding factors using a multivariate binary logistic regression model.

RESULTS

Significantly higher levels of both markers were detected in the CP group in comparison to controls. Weak-to-moderate positive significant correlations between salivary biomarkers and clinical parameters were observed. After binary logistic regression analysis, salivary levels of 8-OHdG >17.35 ng/mL and HNE/α1-PI complex >158.28 ng/mL were independently associated with disease status. Interaction effects among candidate prognostic variables were also noted.

CONCLUSIONS

Increased salivary levels of 8-OHdG and HNE/α1-PI complex may be strong, independent prognostic indicators of the amount and extent of oxidative stress-induced periodontal breakdown. In addition, unstimulated whole saliva samples might reflect a synergistic biologic interactive effect of HNE/α1-PI associated with the aging and smoking cumulative characteristics of periodontal damage.

Protein biomarkers of periodontitis in saliva

Periodontitis is a chronic inflammatory condition of the tissues that surround and support the teeth and is initiated by inappropriate and excessive immune responses to bacteria in subgingival dental plaque leading to loss of the integrity of the periodontium, compromised tooth function, and eventually tooth loss. Periodontitis is an economically important disease as it is time-consuming and expensive to treat. Periodontitis has a worldwide prevalence of 5-15% and the prevalence of severe disease in western populations has increased in recent decades. Furthermore, periodontitis is more common in smokers, in obesity, in people with diabetes, and in heart disease patients although the pathogenic processes underpinning these links are, as yet, poorly understood. Diagnosis and monitoring of periodontitis rely on traditional clinical examinations which are inadequate to predict patient susceptibility, disease activity, and response to treatment. Studies of the immunopathogenesis of periodontitis and analysis of mediators in saliva have allowed the identification of many potentially useful biomarkers. Convenient measurement of these biomarkers using chairside analytical devices could form the basis for diagnostic tests which will aid the clinician and the patient in periodontitis management; this review will summarise this field and will identify the experimental, technical, and clinical issues that remain to be addressed before such tests can be implemented.

Toll-like receptor (TLR) and matrix metalloproteinase (MMP) polymorphisms and periodontitis susceptibility: a meta-analysis

The aim of this study was to determine whether the toll-like receptor (TLR) and matrix metalloproteinase (MMP) polymorphisms confers susceptibility to periodontitis in ethnically different populations. A literature search using PubMed and Embase provided the data to conduct a meta-analysis on the associations between the TLR2 Arg753Gln, TLR4 Asp299Gly, Thr399Ile, MMP-1 -1607 G1/G2 and MMP-9 -1562 C/T polymorphisms and periodontitis. A total of 32 studies (14 on TLR polymorphisms and 18 on MMP polymorphisms) were considered in the meta-analysis. The meta-analysis showed no association between periodontitis and the TLR2 753Arg allele (Odds ratio [OR]=0.962, 95% confidence interval [CI]=0.662-1.400, p=0.841). Meta-analysis of the TLR4 Asp299Gly and Thr399Ile polymorphisms showed no association between periodontitis and the TLR4 299Asp allele in all study subjects (OR=0.984, 95% CI=0.761-1.271, p=0.900; OR=1.030, 95% CI=0.748-1.418, p=0.854). Meta-analysis showed an association between the MMP-1 -1607 G2G2 genotype and periodontitis in Asians (OR=3.778, 95% CI=1.210-11.80, p=0.022). Meta-analysis containing only studies in Hardy-Weinberg equilibrium revealed no association between chronic periodontitis and the MMP-9 -1562TT genotype (OR=0.638, 95% CI=0.265-1.533, p=0.315). This meta-analysis demonstrates a lack of association between the TLR2 Arg753Gln, TLR4 Asp299Gly, Thr399Ile, MMP-9 -1562 C/T polymorphisms and periodontitis, but shows an association between the MMP-1 -1607 G2G2 genotype and periodontitis in Asians.

Salivary MMPs, TIMPs, and MPO levels in periodontal disease patients and controls

BACKGROUND

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases with an important role in physiological and pathological remodeling. Their activity is regulated by tissue inhibitors of matrix metalloproteinases (TIMPs). Excess MMPs and myeloperoxidase (MPO) activity have been associated with loss of tooth supporting tissues in periodontal disease (PD). We investigate the changes in salivary MMP-8, MMP-9, TIMP-1, TIMP-2, and MPO concentrations during PD treatment and compare results with plasma levels.

METHODS

MMP-8, MMP-9, TIMP-1 and TIMP-2 were analyzed by ELISA. Gelatinolytic activity of MMP-9 forms was determined by zymography, and the MPO activity was determined by colorimetric assay.

RESULTS

Subjects were divided into 2 groups: PD and control, which were further divided into 2 subgroups each, namely PD before (PB) and after 3 months (PA) of non-surgical periodontal therapy, and healthy volunteers at baseline (CB) and 3months after baseline (CA). Subgroup PA presented lower gelatinolytic activity and MMP-8 and TIMP-2 concentrations in the saliva compared with PB (p<0.05). The MPO activity was higher in PB compared with CB (p<0.05). There were significant correlations between the gelatinolytic activity of the saliva and MMP-8 and MMP-9 plasma levels. There was a significant correlation between plasma and saliva TIMP-2 levels.

CONCLUSION

These results suggest attenuation of some inflammatory markers in the saliva and plasma after PD treatment. Moreover, correlations between salivary and plasma levels exist for some of these markers.

MMP-9 -1562C>T contributes to periodontitis susceptibility

AIM

The study was conducted to explore the potential association of Matrix metalloproteinases (MMP)-9 -1562C>T with susceptibility to periodontitis.

MATERIALS AND METHODS

Electronic literature searches of PubMed, EMBASE and EBSCO databases were performed. Fixed-effects or random-effects models were used to calculate the pooled odds ratios (ORs) for four genetic comparisons.

RESULTS

Seven eligible studies with a total of 628 cases and 689 controls were recruited in the pooled analysis. We found MMP-9 -1562C>T contributed to decreased risk of chronic periodontitis. Furthermore, the polymorphism was associated with modified risk of periodontitis among Caucasian populations.

CONCLUSIONS

This study indicated that MP-9 -1562C>T might be involved in the development of periodontitis. A replication of our results in independent large analysis populations is necessary to give evidence to our observation.

Matrix metalloproteinases and inflammatory cytokines in oral fluid of patients with chronic generalized periodontitis and various construction materials

We present the results of comparative enzyme-linked immunosorbent assay of matrix metalloproteinases MMP-2, MMP-8, MMP-9; IL-1β and IL-6; tissue inhibitors of MMP (TIMP-1, TIMP-2), and TNF-α. The object of study was oral fluid of practically healthy subjects with intact periodontium and patients with chronic generalized periodontitis with various structural materials of dental restorations. It was found that MMP-9 in oral fluid could be considered as a marker of chronic generalized periodontitis irrespective of the presence or absence of metal dental restorations. The level of MMP-8 surpassed the normal only in oral fluid of patients with chronic generalized periodontitis with metal restorations. The correlations between the studied parameters in patients attest to relatively similar regulation of MMP, IL and TIMP secretion in oral fluid in practically healthy subjects with intact periodontium. In patients with inflammatory destructive periodontal diseases with and without metal dental restorations, the correlation coefficients indicate initiation of biochemical cascade accompanied by activation of cytokine production in response to etiological factors. Patients with periodontitis and metal orthodontic structures showed more pronounced reaction. Orthodontic structures made from chromium-cobalt, or chromium-nickel alloys in the oral cavity of these patients increased the levels of MMP-2, IL-1β and IL-6 in oral fluid.