Macrophage activating factor: A potential biomarker of periodontal health status

Salivary macrophage chemokines as potential biomarkers of gingivitis

OBJECTIVE

The present study aimed to analyze the salivary levels of macrophage-activating factor (MAF), macrophage-chemotactic factor (MCF), and macrophage migration inhibitory factor (MIF) in healthy and gingivitis patients, and to correlate between the concentrations of these chemo attractants with the intensity of gingival inflammation clinically.

METHODS

Sixty saliva specimens were collected from periodontally healthy (n = 30), and gingivitis patients (n = 30). Bleeding on probing (BOP), Visible Plaque Index (VPI), and Simplified Modified Gingival Index (SMGI) were recorded through clinical examination. Salivary MAF, MCF, and MIF concentrations were assayed using enzyme-linked immunosorbent assays (ELISA). Statistical analysis was performed using SPSS (version 28). Total mean score for each biomarker was determined, and descriptive bivariate statistics were conducted to characterize the levels of biomarkers among the study groups. The difference in the biomarker levels among the study groups were analyzed by independent sample t test and one-way ANOVA. The diagnostic ability of the biomarkers was further tested by ROC curve analysis.

RESULTS

Salivary levels of MAF was not significantly different between periodontally healthy individuals and gingivitis patients. The difference in MCF and MIF levels between patients with gingivitis and those with healthy periodontium was statistically significant (p 0.05 and p 0.001, respectively). When examined across the various stages of disease progression, MIF showed statistically significant difference among the three biomarkers (p 0.05). ROC curve analysis further revealed that area under the curve (AUC) for MIF has a better diagnostic capacity than MCF (AUC 0.981 vs. 0.673).

CONCLUSIONS

Our results suggest that MIF could be considered as a potential salivary biomarker for gingivitis.

Effect of Non-surgical Periodontal Treatment on Salivary and Serum Biomarkers in Stage III Grade B and C Periodontitis

BACKGROUND

This study aimed to evaluate the levels of total matrix metalloproteinase-8 (MMP-8), macrophage-activating factors (MAF), macrophage inflammatory protein (MIP)-1α, macrophage colony-stimulating factor (M-CSF), interleukin (IL)-34 in saliva and serum of periodontally healthy, periodontitis stage III grade B (P-III-B) and grade C (P-III-C) participants and to compare the changes after non-surgical periodontal treatment (NSPT).

METHODS

A total of non-smoker and systemically healthy 65 participants, 20 periodontally healthy, 20 P-III-B, and 25 P-III-C were recruited for the study. The periodontal parameters were recorded, saliva and serum samples were obtained from all participants at baseline. In periodontitis groups, the periodontal parameters were reevaluated, and the samples were recollected at 1 and 3 months following the NSPT. MMP-8, MAF, MIP-1α, M-CSF, and IL34 levels were measured by ELISA. Receiver operating characteristics curve was performed for estimating the area under the curve (AUC).

RESULTS

All periodontal parameters were improved in periodontitis groups after NSPT (p<0.05). Among tested molecules, salivary MMP-8 and MAF were higher in both periodontitis groups compared to healthy controls (p<0.05) at baseline and significantly decreased after NSPT (p<0.05) to healthy levels or below. Salivary MMP-8 had the highest diagnostic ability both for P-III-B (AUC:0.78 sensitivity: 80%; specificity: 80%) and P-III-C (AUC:0.88 sensitivity: 88%; specificity: 80%). Moreover, after adjusting for age, periodontitis groups were associated with salivary MMP-8 and MAF levels (p<0.05).

CONCLUSION

The present study showed that high salivary MMP-8 and MAF levels were associated with non-smoker, systemically healthy P-III-B and P-III-C. Moreover, NSPT was remarkably reduced their levels. This article is protected by copyright. All rights reserved.

[Saliva of periodontitis patients promotes macrophage differentiation and activation]

OBJECTIVE

The aim of this study was to investigate the effect of saliva of patients with chronic periodontitis (CPD) on the differentiation, activation, and secretion of osteoclast-maturing mediators of macrophages.

METHODS

A total of 40 saliva samples were collected from healthy donors (n=20) and severe periodontitis patients (n=20). Peripheral blood mononuclear cells (PBMCs) and THP-1 monocyte line cells were challenged with 15% saliva for 5 days. The phenotype, surface marker, and phagocytosis of macrophages were analyzed by flow cytometry and microscopy. Osteoclast-maturing mediators were assayed by using enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

When PBMCs were treated with CPD saliva for 5 days, 61.25%±11.33% of cells were transformed into large granular cells; 86.78%±13.69% of large granular cells were identified as CD14⁺⁺CD16⁺ macrophages. When THP-1 cells were treated with CPD saliva, most cells attached to the bottom of cell culture plates, thereby exhibiting macrophage morphology and releasing additional osteoclast-maturing mediators. Furthermore, the phagocytosis of THP-1 cells considerably increased in the presence of CPD saliva (66.35%±9.67%) compared with medium control (33.33%±7.52%), or healthy saliva (40.71%±3.52%).

CONCLUSIONS

Saliva from patients with CPD can induce macrophage differentiation, activate phagocytose microorganisms, and secrete osteoclast-maturing mediators.

Salmeterol, a Long-Acting β2-Adrenergic Receptor Agonist, Inhibits Macrophage Activation by Lipopolysaccharide From Porphyromonas gingivalis

BACKGROUND

Salmeterol is a long-acting β2-adrenergic receptor agonist used to treat chronic obstructive pulmonary disease. The authors of the current study previously showed that preincubation of primary microglial-enriched cells with salmeterol could inhibit the inflammatory response induced by Escherichia coli lipopolysaccharide (LPS), a Toll-like receptor (TLR)-4 agonist. In this study, the authors sought to determine if salmeterol had a similar inhibitory effect on the inflammatory response of the murine macrophage cell line RAW264.7 and human monocyte THP-1 to LPS from Porphyromonas gingivalis (PgLPS), an oral microbe implicated in the pathogenesis of periodontal disease.

METHODS

RAW264.7 and THP-1 cells were pretreated with salmeterol, followed by PgLPS, and monitored for production of inflammatory mediators by enzyme-linked immunosorbent assay. The nitric oxide concentration and nuclear factor-kappa B (NF-κB) activity were measured by Griess method and secretory alkaline phosphatase reporter activity assay, respectively. Reverse-transcriptase polymerase chain reaction and immunoblot analysis were used to measure messenger RNA and protein levels. Nuclear translocation of NF-κB was detected by immunofluorescence.

RESULTS

Pretreatment with salmeterol significantly inhibited production of proinflammatory mediators by RAW264.7 and THP-1 cells. Salmeterol downregulated PgLPS-mediated phosphorylation of the extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase but not p38 mitogen-activated protein kinases (MAPKs). Salmeterol also attenuated activation of NF-κB via inhibition of nuclear translocation of p65-NFκB, the transcriptional activity of NF-κB and IκBα phosphorylation.

CONCLUSION

Salmeterol can significantly inhibit activation of macrophage-mediated inflammation by PgLPS, suggesting that use of salmeterol may be an effective treatment in inhibiting or lessening the inflammatory response mediated through TLR pathway activation.

Efficacy of scaling and root planing with and without adjunct antimicrobial photodynamic therapy on the expression of cytokines in the gingival crevicular fluid of patients with periodontitis: A systematic review

BACKGROUND

The aim of the present review was to study the efficacy of scaling and root planing (SRP) with and without adjunct antibacterial photodynamic therapy (aPDT) on the expression of cytokines in the gingival crevicular fluid (GCF) of patients with periodontitis.

METHODS

In order to address the focused question: "What is the efficacy of SRP with and without aPDT on the expression of cytokines in the GCF of patients with periodontitis" an electronic search without time or language restrictions was conducted up to and including July 2016 in indexed databases using various key words. The exclusion criteria included reviews, laboratory and experimental studies, case reports, commentaries, letters to the editor, interviews, updates, studies where intervention group received aPDT without previous SRP, and studies where local delivery of antibiotics was used as adjunctive therapy to aPDT.

RESULTS

Six randomized control trials were included in the present systematic review. All studies included a control group which received only SRP. Results from 34% of studies reported lower cytokine levels among individuals receiving adjunct aPDT to SPT compared to patients receiving SRP alone. Selective cytokines reduction in the GCF following SRP with adjunct aPDT compared with SRP alone was reported in 50% of the studies. In one study SRP with adjunct aPDT failed to reduce GCF cytokine concentration.

CONCLUSION

From the literature reviewed the efficacy aPDT as adjunct to SRP in downregulating GCF cytokines remains debatable. Further well-designed studies are needed in this regard.