Cytokines in gingival crevicular fluid of adolescents and young adults

Host and bacterial factors linking periodontitis and rheumatoid arthritis

Observations from numerous clinical, epidemiological and serological studies link periodontitis with severity and progression of rheumatoid arthritis. The strong association is observed despite totally different aetiology of these two diseases, periodontitis being driven by dysbiotic microbial flora on the tooth surface below the gum line, while rheumatoid arthritis being the autoimmune disease powered by anti-citrullinated protein antibodies (ACPAs). Here we discuss genetic and environmental risk factors underlying development of both diseases with special emphasis on bacteria implicated in pathogenicity of periodontitis. Individual periodontal pathogens and their virulence factors are argued as potentially contributing to putative causative link between periodontal infection and initiation of a chain of events leading to breakdown of immunotolerance and development of ACPAs. In this respect peptidylarginine deiminase, an enzyme unique among prokaryotes for Porphyromonas gingivalis, is elaborated as a potential mechanistic link between this major periodontal pathogen and initiation of rheumatoid arthritis development.

Maintaining a protective state for human periodontal tissue

Periodontitis, caused by infection with periodontal pathogens, is primarily characterized by inflammatory bone resorption and destruction of connective tissue. Simply describing periodontitis as a specific bacterial infection cannot completely explain the various periodontal tissue destruction patterns observed. Periodontal tissue damage is thought to be caused by various factors. In recent years, research goals for periodontal pathogens have shifted from searching for specific pathogens to investigating mechanisms that damage periodontal tissues. Bacteria interact directly with the host in several ways, influencing expression and activity of molecules that evade host defenses, and destroying local tissues and inhibiting their repair. The host's innate and acquired immune systems are important defense mechanisms that protect periodontal tissues from attack and invasion of periodontal pathogens, thus preventing infection. Innate and acquired immunity have evolved to confront the microbial challenge, forming a seamless defense network in periodontal tissues. In the innate immune response, host cells quickly detect, via specialized receptors, macromolecules and nucleic acids present on bacterial cell walls, and this triggers a protective, inflammatory response. The work of this subsystem of host immunity is performed mainly by phagocytes, beta-defensin, and the complement system. In addition, the first line of defense in oral innate immunity is the junctional epithelium, which acts as a physical barrier to the entry of oral bacteria and other nonself substances. In the presence of a normal flora, junctional epithelial cells differentiate actively and proliferate apically, with concomitant increase in chemotactic factor expression recruiting neutrophils. These immune cells play an important role in maintaining homeostasis and the protective state in periodontal tissue because they eliminate unwanted bacteria over time. Previous studies indicate a mechanism for attracting immune cells to periodontal tissue with the purpose of maintaining a protective state; although this mechanism can function without bacteria, it is enhanced by the normal flora. A better understanding of the relationship between the protective state and its disruption in periodontal disease could lead to the development of new treatment strategies for periodontal disease.

Evaluation of Levels of Proinflammatory Chemokines MIP-1α and MIP-1β in Gingival Crevicular Fluid of Primary, Mixed and Permanent Dentition

Aim:

This study aims to find out the proinflammatory chemokines macrophage inflammatory protein (MIP)-1α and MIP-1β levels in gingival crevicular fluid (GCF) of primary, mixed, and permanent dentitions.

Materials and Methods:

GCF of 160 individuals (4–15 years of age) was collected by the extracrevicular method. They were categorized into four groups (40 per each group). Group I: subjects with primary dentition (4–5 years of age), Group II: 40 subjects in early transition period (6–8 years), Group III: 40 individuals in the late transition period (9–11 years), and Group IV: 40 individuals with permanent dentition (12–15 years). MIP-lα and MIP-1β levels were determined in the samples of GCF by ELISA method. Data were analyzed by software SPSS Version 20 (IBM SPSS Statistics for Windows, IBM Corp., Armonk, NY: USA).

Results:

MIP-1α and MIP-1β were detected in all samples. The highest mean MIP-1α and MIP-1β concentrations in GCF were detected in the early transition period, while the lowest concentrations were seen in primary dentition group. The chemokine levels were higher in girls than in boys in Group III. There was a substantial rise of MIP-1α and MIP-1β levels during eruption.

Conclusions:

Since levels of MIP-1α and MIP-1β in GCF are positively associated with tooth eruption, they may perhaps be deemed as novel biomarkers in the eruption process.

Evaluation of Four Different Restorative Materials for Restoration of the Periodontal Condition of Wedge-Shaped Defect: A Comparative Study

BACKGROUND This study aimed to conduct a clinical evaluation of four restorative materials for restoration of dental wedge-shaped defect (WSD) and their impacts on periodontal tissues. MATERIAL AND METHODS A total of 280 maxillary premolars with dental WSD were selected from 106 patients; the patient cases were divided into eight groups according to different combinations of restorative materials (flowable resin composites, Dyract compomers, glass ionomer cement (GIC), light-curing composite resin), and WSD positions (approaching gingival and subgingival positions). Gingival crevicular fluid (GCF) volume, levels of aspartate aminotransferase (AST), alkaline phosphatase (ALP), and interleukin-1β (IL-1β) in GCF were analyzed, while probing depth (PD), plaque index (PLI), and sulcus bleeding index (SBI) were also measured. The periodontal conditions of all patients were followed prior to restoration, as well as six months and 12 months after restoration. RESULTS After six months of restoration, the overall clinical success rates of flowable resin composites, Dyract compomers, and light-curing composite resin were greater than those of GIC. GCF volume, GCF-AST, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. After 12 months of restoration, the overall clinical success rates of flowable resin composites and Dyract compomers were greater than those of light-curing composite resin and GIC. GCF volume, GCF-AST, GCF-ALP, IL-1β levels, PD, PLI, and SBI of cases restored by GIC were higher than those restored by the other three materials. CONCLUSIONS Our study provided evidence that the clinical efficacy of flowable resin composites, Dyract compomers, and light-curing composite resin was greater than that of GIC for restoration of dental WSD.

Transcriptome analysis reveals mucin 4 to be highly associated with periodontitis and identifies pleckstrin as a link to systemic diseases

The multifactorial chronic inflammatory disease periodontitis, which is characterized by destruction of tooth-supporting tissues, has also been implicated as a risk factor for various systemic diseases. Although periodontitis has been studied extensively, neither disease-specific biomarkers nor therapeutic targets have been identified, nor its link with systemic diseases. Here, we analyzed the global transcriptome of periodontitis and compared its gene expression profile with those of other inflammatory conditions, including cardiovascular disease (CVD), rheumatoid arthritis (RA), and ulcerative colitis (UC). Gingival biopsies from 62 patients with periodontitis and 62 healthy subjects were subjected to RNA sequencing. The up-regulated genes in periodontitis were related to inflammation, wounding and defense response, and apoptosis, whereas down-regulated genes were related to extracellular matrix organization and structural support. The most highly up-regulated gene was mucin 4 (MUC4), and its protein product was confirmed to be over-expressed in periodontitis. When comparing the expression profile of periodontitis with other inflammatory diseases, several gene ontology categories, including inflammatory response, cell death, cell motion, and homeostatic processes, were identified as common to all diseases. Only one gene, pleckstrin (PLEK), was significantly overexpressed in periodontitis, CVD, RA, and UC, implicating this gene as an important networking link between these chronic inflammatory diseases.

Correlation of the interleukin-29 levels in crevicular fluid and plasma with the genetic polymorphism in chronic and aggressive periodontitis patients

OBJECTIVE

To assess the effect of single nucleotide polymorphism (SNP) on the Interleukin (IL-29) quantity in gingival crevicular fluid (GCF) and plasma of chronic and aggressive periodontitis patients.

DESIGN

Patients with periodontal health (n=30), chronic generalized periodontitis (n=30) and generalized aggressive periodontitis (n=30) were subjected to IL-29 quantity estimation in GCF and plasma using enzyme linked immunosorbent assay and was correlated with IL-29 SNP (rs30461) using polymerase chain reaction.

RESULTS

IL-29 concentration in GCF and plasma was highest in aggressive periodontitis patients (114.17 ± 95.07pg/ml and 149.69 ± 109.90pg/ml respectively). The least concentration was found in subjects with healthy periodontium (47.50 ± 37.75pg/ml and 54.52 ± 37.53pg/ml) and in chronic periodontitis it was found to be 65.01 ± 41.26pg/ml and 81.17 ± 46.23pg/ml. The difference in the quantity of IL-29 in GCF and plasma among different groups was statistically significant (p<0.001 and p<0.001 respectively). rs30461 polymorphism of IL-29 analysis revealed that difference in the prevalence of A/A, A/G and G/G genotype among three groups was not statistically significant (p=0.097).

CONCLUSION

Increased quantity of IL-29 in GCF and plasma of subjects with periodontitis suggests a role in pathogenesis of periodontitis and the SNP (rs30461) is not related to susceptibility to periodontitis in this population of Indian individuals.

Defensins and LL-37: a review of function in the gingival epithelium

Antimicrobial peptides represent an important aspect of the innate defense system that contributes to the control of bacterial colonization and infection. As studies have progressed it has become clear that antimicrobial peptides manifest other functions in addition to their antimicrobial effects. These functions include chemotaxis of numerous types of host cells involved in both the innate and adaptive immune responses. In this review, the antimicrobial activity, the regulation and the contribution to host homeostasis of alpha-defensins and LL-37, as well as of beta-defensins, are discussed in the context of their specific tissue locations in the junctional epithelium and oral epithelium, respectively.

Periodontopathogens levels and clinical response to periodontal therapy in individuals with the interleukin-4 haplotype associated with susceptibility to chronic periodontitis

Periodontitis is an inflammatory disease that results from an interaction between dental biofilm agents and the host immune-inflammatory response. Periodontopathogenic organisms, such as Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, as well as the host's susceptibility, represented by the host's genetic makeup, are the key factors that influence this complex disease. Recently, we identified haplotypes in the IL4 gene that were associated with chronic periodontitis (CP). This study aimed to evaluate whether subjects with different IL4 haplotypes (TCI/CCI and TTD/CTI) would be differentially colonized by periodontopathogens and whether they would respond differently to non-surgical periodontal therapy. Thirty-nine patients carrying the IL4 haplotype of genetic susceptibility to CP (IL4+) or protection against CP (IL4-) were evaluated. Those groups were further subdivided into individuals with CP (CP IL4+ or CP IL4-) and those that were periodontally healthy (H) (H IL4+ or H IL4-). CP patients were submitted to non-surgical periodontal therapy. Clinical and microbiological analyses were performed considering the data at baseline and 45 and 90 days after periodontal therapy. Periodontopathogens levels were evaluated by absolute quantitative polymerase chain reaction (qPCR). The baseline data revealed that the total levels of periodontopathogens were higher in the CP IL4+ than in the CP IL4- groups. Clinical analyses revealed that the periodontal therapy was equally effective, independent of the subject's IL4 genetic load. The TCI/CCI IL4 haplotype, previously associated with genetic susceptibility to CP, was also associated with increased levels of periodontopathogenic bacteria, but this genetic background did not influence the response to non-surgical periodontal treatment.

Gingival crevicular fluid and plasma acute-phase cytokine levels in different periodontal diseases

BACKGROUND

The aim of the present study is to investigate gingival crevicular fluid (GCF) and plasma acute-phase cytokines, interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-11 (IL-11), oncostatin M (OSM), and leukemia inhibitory factor (LIF) levels in patients with different periodontal diseases.

METHODS

Eighty individuals were included in this study; 20 with chronic periodontitis (CP), 20 with generalized aggressive periodontitis (GAgP), 20 with gingivitis, and 20 classified as healthy (H). Probing depth, clinical attachment level, plaque index, and papilla bleeding index were recorded. Plasma and GCF IL-1β, IL-6, IL-11, OSM, and LIF levels were analyzed by enzyme-linked immunosorbent assay.

RESULTS

CP and GAgP groups had significantly higher GCF IL-1β, IL-6, and IL-11 levels when compared with the H group (P <0.05). Conversely, GCF LIF levels of the CP and GAgP groups were lower than those of the H group (P <0.05). GCF OSM levels did not differ significantly among study groups. Plasma levels of all the cytokines studied were not significantly different among the study groups.

CONCLUSIONS

Based on the present data, elevated IL-1β, IL-6, and IL-11 GCF levels, but not plasma levels, are suggested as reliable inflammatory biomarkers in periodontal diseases. Decreased LIF levels in diseased groups might reflect the possible beneficial effects of LIF in the modulation of inflammatory response in gingiva.

The influence of sex hormones on proinflammatory cytokines in gingiva of periodontally healthy premenopausal women

BACKGROUND AND OBJECTIVE

The aim of this work was to investigate any correlation between the fluctuation of levels of specific proinflammatory cytokines in gingival crevicular fluid and the fluctuation of sex hormones in peripheral blood at ovulation and progesterone peak.

MATERIAL AND METHODS

Eighteen premenopausal women with normal and consistent menstrual cycles and healthy periodontium were included in this study. The exclusion criteria were as follows: (i) pregnancy; (ii) use of oral contraceptives; (iii) metabolic or systemic disease that might affect the periodontium; (iv) use of antimicrobial or nonsteroidal anti-inflammatory drugs during the past 6 mo; and (v) smoking. The measurements were performed at two specific time points for each participant [(i) on the day of ovulation; and (ii) on the day of the progesterone peak) and included the following: (i) plaque index; (ii) bleeding on probing; and (iii) the gingival crevicular fluid levels of interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor-α (TNF-α).

RESULTS

During the menstrual cycle, plaque index values remained unchanged (0.71 ± 0.07 at ovulation; 0.73 ± 0.08 at progesterone peak; p > 0.05), as did bleeding on probing (0.35 ± 0.07 at ovulation; 0.41 ± 0.07 at progesterone peak; p > 0.05). At ovulation, mean gingival crevicular fluid levels were as follows: IL-1β, 13.3 pg/sample; IL-6, 5.9 pg/sample; IL-8, 18.7 pg/sample; and TNF-α, 25.9 pg/sample. The corresponding values at progesterone peak were as follows: 14.1, 10.1, 19.5 and 26.3 pg/sample. Only IL-6 gingival crevicular fluid levels were significantly different between ovulation and progesterone peak (p < 0.05). This could reflect sensitivity to subclinical amounts of plaque and biofilm constituents.

CONCLUSION

The subclinical increase of IL-6 at progesterone peak is not accompanied by clinical changes in the periodontium.