Matrix metalloproteinase-8 levels in oral samples as a biomarker for periodontitis in the Chinese population: an observational study

Importance of Metalloproteinase 8 (MMP-8) in the Diagnosis of Periodontitis

Periodontitis is a complex condition. Left untreated, it leads to tooth loss and the need for prosthetic treatment. The incidence of periodontitis is steadily increasing, so new methods are being sought to aid in the diagnosis of the disease. Among the methods postulated is the determination of concentrations of bioactive compounds which include extracellular matrix metalloproteinases (MMPs). These enzymes are present in various structural elements of the stomatognathic system. The most promising enzyme of this group appears to be metalloproteinase 8 (MMP-8). MMP-8 assays are performed in gingival fluid or saliva, and MMP-8 levels have been shown to be higher in patients with periodontitis compared to healthy subjects and correlated with some clinical parameters of the condition and the severity of the disease. In addition, the preliminary usefulness of this enzyme in evaluating the effectiveness of periodontal treatment and doxycycline therapy has been demonstrated. Determination of the active form of MMP-8 (aMMP-8) in oral rinse fluid using off-the-shelf assays shows the highest potential. Despite reports about aMMP-8 and promising data on the role of MMP-8 in periodontal diagnosis, a clear determination of the usefulness of this enzyme requires further research.

Assessing salivary matrix metalloproteinase‐8 in prostate cancer patients undergoing androgen deprivation therapy

Introduction

Matrix metalloproteinase‐8 (MMP‐8) is considered as one of the most promising diagnostic markers for periodontal disease. Androgen deprivation therapy (ADT) has been correlated with impaired collagen synthesis and an increase in periodontal tissue susceptibility to pathogenic microorganisms.

Objective

This study aims to investigate the impact of ADT on salivary MMP‐8 level and periodontal parameters, which might be useful in monitoring periodontal disease in prostate cancer patients undergoing ADT.

Materials and Methods

A total of 88 subjects were selected and were divided into two groups: Group I included n = 78 PC patients who have been undergoing ADT); Group II included n = 10 healthy individuals. Periodontal parameters such as plaque index (PI), gingival index (GI), periodontal probing depth (PPD), and clinical attachment level (CAL) were examined. The salivary MMP‐8 level was estimated by using the sandwich enzyme‐linked immunosorbent assay method.

Results

Significant differences in mean salivary MMP‐8 level were found between PC patients undergoing ADT and healthy individuals. Salivary MMP‐8 levels of all individuals were positively correlated with GI, PI, PPD, and CAL. Salivary MMP‐8 can distinguish between periodontitis and healthy individuals with an accuracy of about 80%.

Conclusion

Salivary MMP‐8 levels were found to be higher in prostate cancer patients undergoing ADT compared to healthy individuals.

Effects of contaminated surface water and groundwater from a rare earth mining area on the biology and the physiology of Sprague-Dawley rats

Previous studies have shown that an effective damage detection method for model rats from macro individual to micro cellular, was applied to assess the groundwater quality from rare earth metals tailings seepage. To determine whether it is universal method for measuring the toxicological damage caused by contaminated water around other mining areas to organisms at the organ-tissue-cell-chromosome-gene level. In this study, a rare earth mining area in North China was used as research base. Firstly, the core pollution factors in surface water and groundwater from five different sites were analyzed. Then, the degree of toxicological damage to Sprague-Dawley (SD) rats caused by contaminated water were systematically assessed using biological methods. Finally, the possible molecular mechanism of toxicological damage was further discussed. The synthesis results showed that the main pollution factors were some metal elements (Mn, Zn, Co, Ni) and rare earth elements (Sc, Nb, La, Ce, Pr, Dy and Y), which might cause significant DNA genetic damage to SD rats. Further, differential gene expression profile showed that DNA damage-inducible genes (Gadd45g and Ddit4), immunity-related genes (Mpo, Slpi and Elane) and two cancer-related genes (Mmp8 and Ltf) were used as a new prognostic and predictive biomarker for biosafety assessment. Therefore, this study provides a possible molecular mechanism for the toxicological damage, and also it provides a universal method to scientifically and effectively evaluate the water pollution risk for other mining areas.

Label-free quantitative proteomic analysis of gingival crevicular fluid to identify potential early markers for root resorption

Background

Orthodontically-induced root resorption is an iatrogenic effect and it cannot be examined regularly due to the harmful effects of sequential doses of radiation with more frequent radiography. This study aims to compare protein abundance (PA) of pre-treatment and during orthodontic treatment for root resorption and to determine potential early markers for root resorption.

Methods

Ten subjects (n = 10) who had upper and lower fixed appliances (MBT, 3 M Unitek, 0.022″ × 0.028″) were recruited for this study. Human gingival crevicular fluid (GCF) was obtained using periopaper strips at pre-treatment (T0), 1 month (T1), 3 months (T3), and 6 months (T6) of orthodontic treatment. Periapical radiographs of the upper permanent central incisors were taken at T0 and T6 to measure the amount of root resorption. Identification of changes in PA was performed using liquid chromatography-tandem mass spectrometry. Student’s t-test was then performed to determine the significance of the differences in protein abundance before and after orthodontic treatment.

Results

Our findings showed that all ten subjects had mild root resorption, with an average resorption length of 0.56 ± 0.30 mm. A total of 186 proteins were found to be commonly present at T0, T1, T3, and T6. There were significant changes in the abundance of 16 proteins (student’s t-test, p ≤ 0.05). The increased PA of S100A9, immunoglobulin J chain, heat shock protein 1A, immunoglobulin heavy variable 4–34 and vitronectin at T1 suggested a response to stress that involved inflammation during the early phase of orthodontic treatment. On the other hand, the increased PA of thymidine phosphorylase at T3 suggested growth promotion and, angiogenic and chemotactic activities.

Conclusions

The identified proteins can be potential early markers for root resorption based on the increase in their respective PA and predicted roles during the early phase of orthodontic treatment. Non-invasive detection of root resorption using protein markers as early as possible is extremely important as it can aid orthodontists in successful orthodontic treatment.

Association of MMP-8 rs2012390 and rs11225394 polymorphisms with osteonecrosis of the femoral head risks: Evidence from a meta-analysis

BACKGROUND

The association of MMP-8 rs2012390 and rs11225394 polymorphisms with osteonecrosis of the femoral head (ONFH) risks was investigated in several studies with conflicting results. We performed the meta-analysis to evaluate the association between them.

METHODS

Potentially relevant literatures were searched from the electronic databases of PubMed, Web of Science, and Cochrane Library. All databases were searched up to May 6, 2018. The strength of associations of the MMP-8 rs2012390 and rs11225394 polymorphisms with ONFH risk was assessed by crude odds ratios (ORs) with their 95% confidence intervals (CIs) under different genetic models.

RESULTS

A total of 1469 cases diagnosed with ONFH and 1211 healthy controls were included in the current meta-analysis. A remarkable association between rs11225394 in the MMP-8 gene and an increased risk of ONFH was found (allele model: OR = 1.33, 95% CI = 1.09-1.61, P = .005; heterozygote model: OR = 1.39, 95% CI = 1.13-1.71, P = .002; dominant model: OR = 1.40, 95% CI = 1.14-1.73, P = .002, respectively). Meanwhile, a significant association between MMP-8 rs2012390 and the decreased risk of ONFH was found in heterozygote model (OR = 0.63, 95% CI = 0.51-0.77, P < .00001).

CONCLUSION

The meta-analysis results showed a remarkable association between rs11225394 in MMP-8 gene and an increased risk of ONFH and a significant association between MMP-8 rs2012390 and the decreased risk of ONFH.