Glycated Albumin and Calprotectin Levels in Gingival Crevicular Fluid From Patients With Periodontitis and Type 2 Diabetes

Evaluation of salivary glycated albumin in periodontitis patients with and without type 2 diabetes mellitus and its changes with non-surgical periodontal therapy

Background

Bidirectional relationship exists between diabetes mellitus and periodontitis. Glycated albumin is an emerging biomarker to assess intermediate glycemic control. Salivary glycated albumin has not been evaluated in periodontitis.

Aim

The aim of the study was to compare salivary glycated albumin in periodontitis patients with and without diabetes mellitus before and after periodontal therapy.

Materials and Methods

This comparative cross-sectional study was conducted in the Department of Periodontics. Ninety subjects (mean age 41.8 ± 6.82) were categorized into three groups. Clinical examination and saliva sample collection were done at baseline and 4 weeks after scaling and root debridement. Salivary glycated albumin levels were estimated using an enzyme-linked immunosorbent assay. One-way analysis of variance with post hoc test and paired t-test was done for inter- and intra-group comparison. The optimal cut-off value was calculated using the receiver operating characteristic curve and by maximization of the Youden index.

Results

Mean salivary glycated albumin was the highest in diabetic patients followed by non-diabetic periodontitis patients and least in healthy controls. All the intergroup comparisons were significant. A cut-off value of 72.19 ng/ml of salivary glycated albumin could predict diabetic status with a sensitivity and specificity of 75%. Salivary glycated albumin was significantly reduced in a similar manner in both groups after periodontal therapy (19.4% and 18.5%).

Conclusion

Periodontitis patients with diabetes mellitus were presented with the highest salivary glycated albumin. Non-surgical periodontal therapy resulted in a similar reduction of salivary glycated albumin in periodontitis with and without diabetes mellitus.

Novel Insight into the Mechanisms of the Bidirectional Relationship between Diabetes and Periodontitis

Periodontitis and diabetes are two major global health problems despite their prevalence being significantly underreported and underestimated. Both epidemiological and intervention studies show a bidirectional relationship between periodontitis and diabetes. The hypothesis of a potential causal link between the two diseases is corroborated by recent studies in experimental animals that identified mechanisms whereby periodontitis and diabetes can adversely affect each other. Herein, we will review clinical data on the existence of a two-way relationship between periodontitis and diabetes and discuss possible mechanistic interactions in both directions, focusing in particular on new data highlighting the importance of the host response. Moreover, we will address the hypothesis that trained immunity may represent the unifying mechanism explaining the intertwined association between diabetes and periodontitis. Achieving a better mechanistic insight on clustering of infectious, inflammatory, and metabolic diseases may provide new therapeutic options to reduce the risk of diabetes and diabetes-associated comorbidities.

Glycation of Host Proteins Increases Pathogenic Potential of Porphyromonas gingivalis

The non-enzymatic addition of glucose (glycation) to circulatory and tissue proteins is a ubiquitous pathophysiological consequence of hyperglycemia in diabetes. Given the high incidence of periodontitis and diabetes and the emerging link between these conditions, it is of crucial importance to define the basic virulence mechanisms employed by periodontopathogens such as Porphyromonas gingivalis in mediating the disease process. The aim of this study was to determine whether glycated proteins are more easily utilized by P. gingivalis to stimulate growth and promote the pathogenic potential of this bacterium. We analyzed the properties of three commonly encountered proteins in the periodontal environment that are known to become glycated and that may serve as either protein substrates or easily accessible heme sources. In vitro glycated proteins were characterized using colorimetric assays, mass spectrometry, far- and near-UV circular dichroism and UV–visible spectroscopic analyses and SDS-PAGE. The interaction of glycated hemoglobin, serum albumin and type one collagen with P. gingivalis cells or HmuY protein was examined using spectroscopic methods, SDS-PAGE and co-culturing P. gingivalis with human keratinocytes. We found that glycation increases the ability of P. gingivalis to acquire heme from hemoglobin, mostly due to heme sequestration by the HmuY hemophore-like protein. We also found an increase in biofilm formation on glycated collagen-coated abiotic surfaces. We conclude that glycation might promote the virulence of P. gingivalis by making heme more available from hemoglobin and facilitating bacterial biofilm formation, thus increasing P. gingivalis pathogenic potential in vivo.

Diagnosis of inflammatory peri-implant diseases using an immunochromatographic assay for calprotectin in peri-implant crevicular fluid

Background

The incidence rate of peri-implant diseases is increasing with implant placement. Early detection of peri-implant diseases is important to prevent and treat these diseases, and a simple and objective diagnostic method is expected. Immunochromatographic (IC) assays are used for rapid diagnostic methods for some diseases. The aim of this clinical study was to determine the amount of calprotectin, an inflammatory marker, in peri-implant crevicular fluid (PICF) using an IC chip, and estimate the possibility of this diagnostic system.

Methods

Forty-six individuals with dental implants participated in a pilot study. PICF samples were collected from the peri-implant sites with or without inflammation after clinical examinations including probing depth (PD), bleeding on probing (BOP) and gingival index (GI). Calprotectin in PICF was determined by an IC chip and enzyme-linked immunosorbent assay (ELISA) for calprotectin. The density of calprotectin line on the IC chip was measured using an IC reader (IC reader value). The relationship between IC reader value and ELISA value or clinical parameters was investigated. A receiver operating characteristic (ROC) curve analysis of IC reader value of calprotectin was performed to predict inflammation in peri-implant diseases.

Results

IC reader value of calprotectin was significantly correlated with its ELISA value and PD. IC reader values of calprotectin in PICF samples from periodontal sites with GI-1 and GI-2, and with BOP-positive sites were significantly higher than those of PICF samples from GI-0 sites, and BOP-negative sites, respectively. The IC reader value for calprotectin in PICF samples from inflammatory diseased sites was significantly higher than that of non-diseased sites. ROC analysis suggested that the IC reader value of PICF calprotectin was useful for predicting inflammatory peri-implant diseases.

Conclusion

IC assay for PICF calprotectin may be a possible system for diagnosing the inflammatory peri-implant diseases.

Calprotectin levels in gingival crevicular fluid and serum of patients with chronic periodontitis and type 2 diabetes mellitus before and after initial periodontal therapy

BACKGROUND

This study is aimed to compare the total amount of calprotectin in gingival crevicular fluid (GCF) and the concentration of calprotectin in serum among the patients with type 2 diabetes mellitus and chronic periodontitis (DM-P), the patients with chronic periodontitis (CP) and the healthy controls, as well as the variation of these indicators before and three months after the initial periodontal therapy for the DM-P patients.

METHODS

35 patients with DM-P patients, 32 patients with CP patients, and 43 healthy controls were recruited. Calprotectin levels in serum and GCF, periodontal parameters, fasting blood glucose (FBG), and HbA1c were measured at baseline for all the groups and three months after the initial periodontal therapy for the DM-P patients.

RESULTS

At baseline, the calprotectin levels in GCF and serum were the highest in DM-P, followed by CP, and the lowest in healthy controls. GCF calprotectin was significantly and positively correlated with serum calprotectin and probing depth (PD), while serum calprotectin had a significant positive correlation with GCF calprotectin and HbA1c. Periodontal parameters, HbA1c, and serum and GCF calprotectin became significantly reduced after the initial periodontal treatment. The reduction of serum calprotectin was consistent with that of HbA1c, while the decrease of GCF calprotectin was in agreement with that of PD, attachment loss (AL), and bleeding on probing (BOP).

CONCLUSIONS

The levels of calprotectin in serum and GCF in the DM-P patients are significantly higher than those in CP patients and healthy controls, which significantly reduced 3 months after the initial periodontal therapy. Furthermore, it suggests diabetic patients might exhibit more pronounced inflammation periodontally and systemically.

Role of Calprotectin as a Biomarker in Periodontal Disease

Periodontal disease (PD) is a common infectious and inflammatory disease characterised by inflammation of tissues surrounding and supporting the teeth and destruction of the associated alveolar bone, eventually resulting in tooth loss. This disease is caused by periodontopathic bacteria in plaque biofilm and resultant innate and adaptive immune responses in periodontal tissues. Calprotectin (CLP) is a calcium-binding protein of the S-100 protein family and is found to be induced by activated granulocytes, monocytes, and epithelial cells. CLP has been shown to play an important role in numerous inflammatory diseases and disorders. Increasing evidence indicates that CLP is involved in the progression of PD, and its levels may be associated with disease severity and outcome of periodontal treatments. This review will summarise recent studies regarding the presence, regulation, and function of CLP in PD. The findings indicate that CLP may be an effective biomarker for diagnosis and treatment for the PD.

Gingival crevicular fluid as a source of biomarkers for periodontitis

In evaluating the pathogenesis of periodontal diseases, the diagnostic potential of gingival crevicular fluid has been extensively explored during the last twenty years, from initially just confirming health and disease states to more recently investigating it as a potential prognostic tool. As host susceptibility is a critical determinant in periodontal disease pathogenesis, the inflammatory mediator levels present in gingival crevicular fluid represent relevant risk indicators for disease activity. Considerable work has been carried out to identify the many different cytokine inflammatory pathways and microbial stimuli that are associated with periodontal disease pathogenesis. Now, 'omics' approaches aim to summarize how these pathways interact and probably converge to create critical inflammatory networks. More recently, gingival crevicular fluid metabolomics appears promising as an additional diagnostic method. Biofilm structure and the host inflammatory response to the microbial challenge may induce specific inflammatory signatures. Host genetics and epigenetics may also modulate microbial colonization, adding to the multiplicity of potential causal pathways. Omics analyses of gingival crevicular fluid, measuring microbial and host interactions in association with the onset and progression of periodontal diseases, still show the potential to expand the landscape for the discovery of diagnostic, prognostic and therapeutic markers.

Association of calprotectin with leukocyte chemotactic and inflammatory mediators following acute aerobic exercise

The objective of this study was to examine whether acute aerobic exercise-mediated calprotectin in plasma would be associated with monocyte chemotactic protein-1 (MCP-1), myeloperoxidase (MPO), and interleukin-6 (IL-6) in healthy individuals. Eleven healthy participants, aged 18 to 30 years, were recruited to perform a 30-min bout of aerobic exercise at 75% maximal oxygen uptake. Acute aerobic exercise elicited a significant elevation across time in plasma calprotectin, MCP-1, MPO, and IL-6. Body mass index (BMI) was positively correlated with calprotectin area-under-the-curve with "respect to increase" (AUCi) and IL-6 AUCi. Furthermore, calprotectin AUCi was positively correlated with IL-6 AUCi and MPO AUCi, even after controlling for BMI. Although MPO AUCi was positively correlated with IL-6 AUCi, this relationship no longer existed after controlling for BMI. These results suggest that acute aerobic exercise could mediate innate immune response associated with calprotectin and its related leukocyte chemotactic and inflammatory mediators, especially in individuals with elevated BMI.

YKL-40 level in gingival crevicular fluid from patients with periodontitis and type 2 diabetes

OBJECTIVE

YKL-40 is a chitin-binding glycoprotein, the level of which increases in inflammatory diseases, diabetes mellitus (DM), cardiovascular diseases, and tumors. Gingival crevicular fluid (GCF) contains many proteins and markers of periodontitis. The purpose of this study was to investigate YKL-40 level in GCF from patients with periodontitis and DM and the association between YKL-40 level and chronic periodontitis (CP) or DM.

SUBJECTS AND METHODS

The subjects were 121 patients with DM, CP, DM and periodontitis (DM-P), and healthy subjects (H). GCF was collected using paper strips after the sites for GCF collection were clinically evaluated for probing depth (PD), gingival index (GI), and bleeding on probing (BOP). YKL-40 in GCF was identified by Western blotting, and its level was determined by ELISA.

RESULTS

YKL-40 was contained in GCF samples from H, DM, CP, and DM-P sites, and its levels (amount and concentration) in CP and DM-P were significantly higher than those in H and DM. GCF YKL-40 level significantly correlated with PD and GI, and its level in BOP-positive sites was significantly higher than that in BOP-negative ones.

CONCLUSIONS

GCF YKL-40 level was elevated in periodontitis, but not DM. YKL-40 in GCF may be an inflammatory marker for periodontitis.