Levels of interleukin 1 beta in tissue from sites of active periodontal disease

Mimicking and in vitro validating chronic inflammation in human gingival fibroblasts

OBJECTIVE

The aim of this study was to identify and validate in vitro conditions that may mimic the translational, cytokine and chemokine profiles observed in human inflamed gingiva in vivo.

DESIGN

Primary human gingiva fibroblast cells (HFIB-G) were cultured under serum starvation conditions (0 - 10 %), supplemented with increasing lipopolysaccharide (LPS) concentrations (0.1, 1, or 10 µg/ml) from two bacterial strains E. coli and P. gingivalis and 0.1, 1, or 10 ng/ml recombinant interleukin 1β (IL-1β), alone or in combinations. The levels of cytokines/chemokines were measured in the cell culture medium by Luminex, and gene expression was quantified by Affymetrix microarrays at 24, 48 and 72 h.

RESULTS

Inflammation markers were not elevated after stimulation with P. gingivalis LPS, while E. coli LPS and IL-1β individually increased the secretion of interleukin 6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) to the cell culture medium. IL-1β administration also increased the secretion of several factors, including tumor necrosis factor (TNFα). However, the combination of 1 µg/ml E. coli LPS, 1 ng/ml IL-1β and serum starvation led to increased secretion of IL-6, TNFα, in addition to other factors found in inflamed tissue. Gene expression analyses revealed that this combination not only enhanced the expression interleukins/chemokines genes but also T helper cell signaling and matrix metalloproteinases.

CONCLUSION

Serum reduction in cell culture medium together with the administration of E. coli LPS and IL-1β resulted in gene expression and secreted cytokine/chemokine profiles similar to that found in vivo during chronic inflammation.

Insight into the role of macrophages in periodontitis restoration and development

Periodontitis is one of the chronic diseases that have the greatest impact on human health, and it is associated with several other chronic diseases. Tissue damage associated with periodontitis is often connected with immune response. Immune cells are a crucial component of the human immune system and are directly involved in periodontitis during the inflammatory phase of the disease. Macrophages, as a key component of the immune system, are responsible for defence, antigen presentation and phagocytosis in healthy tissue. They are also closely linked to the development and resolution of periodontitis, through mechanisms such as macrophage polarization, pattern recognition receptors recognition, efferocytosis, and Specialized Pro-resolving Mediators (SPMs) production. Additionally, apoptosis and autophagy are also known to play a role in the recovery of periodontitis. This review aims to investigate the aforementioned mechanisms in more detail and identify novel therapeutic approaches for periodontitis.

Dental Pathophysiology of Odontogenic Sinusitis: Periodontitis

Periodontitis is a highly prevalent oral microbial biofilm-driven chronic inflammatory disease. If unmanaged, periodontitis leads to progressive destruction of the ligamentous attachments of teeth to the alveolar bone and resorption of the alveolar bone. It eventually leads to tooth hypermobility and loss. Periodontitis commonly causes overlying maxillary sinus inflammation (mucositis), reflected on radiographic imaging as maxillary sinus mucosal thickening. While uncommon, advanced periodontitis (stage III/IV) or chronic perio-endo lesions can lead to purulent odontogenic sinusitis (ODS). This article describes periodontitis pathophysiology, diagnostic features, and its potential to cause ODS. Clinical practice guideline conform therapy is very successful in managing periodontitis and enabling long-term tooth retention. Localized tooth extration is reserved to end-stage disease.

Effect of erbium, chromium-doped: yttrium, scandium, gallium, and garnet laser-assisted periodontal therapy using radial firing tip during early healing period: a randomized controlled split-mouth clinical trial

BACKGROUND

This study aimed to demonstrate the efficacy of erbium, chromium-doped:yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser-assisted nonsurgical periodontal therapy in periodontitis patients during 8 weeks of healing.

METHODS

A split-mouth, single-blinded, randomized controlled clinical trial was conducted on 12 patients diagnosed with stage III/IV periodontitis and had a minimum of two teeth with probing pocket depth (PPD) > 5 mm in at least two quadrants. Upon randomization, each quadrant was assigned for conventional scaling and root planing (SRP) procedure or laser-assisted therapy (SRP + laser) using radial firing tip (RFPT 5, Biolase). Clinical measurements and gingival crevicular fluid collection were performed for statistical analysis.

RESULTS

In the initial statistical analysis on the whole subject teeth, modified gingival index (MGI) reduction was greater in test group at 1(P = 0.0153), 4 (P = 0.0318), and 8 weeks (P = 0.0047) compared to the control in the same period. PPD reduction at 4 weeks in test group was -1.67 ± 0.59 showing significant difference compared to the control (-1.37 ± 0.63, P = 0.0253). When teeth with mean PPD ≥5 mm were sorted, MGI decrease was significantly greater in test group at 1 (P=0.003) and 8 week (P=0.0102) follow-ups. PPD reduction was also significantly greater in test group at 4 week period (-1.98 ± 0.55 vs -1.58 ± 0.56, test vs control, P=0.0224).

CONCLUSIONS

Er,Cr:YSGG-assisted periodontal therapy is beneficial in MGI and PPD reductions during early healing period.

Single-cell transcriptome analysis reveals periodontal ligament fibroblast heterogeneity with distinct IL-1β and RANKL expression in periodontitis

Periodontitis (PD) is an inflammatory disease with alveolar bone destruction by osteoclasts (OCs). In PD, both inflammation and OC activation are significantly influenced by periodontal ligament fibroblasts (PDL-Fib). Yet, whether PDL-Fib has heterogeneity and whether distinct PDL-Fib subsets have specific functions have not been investigated. In this study, we discovered the complexity of PDL-Fib in PD, utilizing single-cell RNA sequencing data from human PD patients. We identified distinct subpopulations of PDL-Fib: one expressing interleukin-1 beta (IL-1β) and another expressing the receptor activator of nuclear factor-kappa B ligand (RANKL), both crucial in OC differentiation and bone resorption. In periodontal tissues of mice with PD, active IL-1β, cleaved caspase 1, and nucleotide-binding oligomerization domain-like receptor 3 (NLPR3) were significantly elevated, implicating the NLRP3 inflammasome in IL-1β production. Upon stimulation of PDL-Fib with LPS from Porphyromonas gingivalis (pg), the most well-characterized periodontal bacteria, a more rapid increase in IL-1β, followed by RANKL induction, was observed. IL-1β and tumor necrosis factor alpha (TNF-α), another LPS-responsive cytokine, effectively increased RANKL in PDL-Fib, suggesting an indirect effect of pgLPS through IL-1β and TNF-α on RANKL induction. Immunohistological analyses of mouse periodontal tissues also showed markedly elevated levels of IL-1β and RANKL upon PD induction and displayed separate locations of IL-1β-expressing PDL-Fib and RANKL-expressing PDL-Fib in PD. The heterogenic feature of fibroblasts expressing IL-1β and RANKL was also mirrored in our combined cross-tissue single-cell RNA sequencing datasets analysis. In summary, our study elucidates the heterogeneity of PDL-Fib, highlighting distinct functional groups for producing RANKL and IL-1β, which collectively promote OC generation and bone destruction in PD.

Pathogenesis of non-infection related inflammatory root resorption in permanent teeth: A narrative review

BACKGROUND

The mechanism of action of root resorption in a permanent tooth can be classified as infection-related (e.g., microbial infection) or non-infection-related (e.g., sterile damage). Infection induced root resorption occurs due to bacterial invasion. Non-infection-related root resorption stimulates the immune system through a different mechanism.

OBJECTIVES

The aim of this narrative review is to describe the pathophysiologic process of non-infection-related inflammatory processes involved in root resorption of permanent teeth.

METHODS

A literature search on root resorption was conducted using Scopus (PubMed and Medline) and Google Scholar databases to highlight the pathophysiology of bone and root resorption in non-infection-related situations. The search included key words covering the relevant category. It included in vitro and in vivo studies, systematic reviews, case series, reviews, and textbooks in English. Conference proceedings, lectures and letters to the editor were excluded.

RESULTS

Three types of root resorption are related to the non-infection mechanism of action, which includes surface resorption due to either trauma or excessive orthodontic forces, external replacement resorption and external cervical resorption. The triggers are usually damage associated molecular patterns and hypoxia conditions. During this phase macrophages and clastic cells act to eliminate the damaged tissue and bone, eventually enabling root resorption and bone repair as part of wound healing.

DISCUSSION

The resorption of the root occurs during the inflammatory phase of wound healing. In this phase, damaged tissues are recognized by macrophages and neutrophiles that secrete interlaukines such as TNF-α, IL-1, IL-6, IL-8. Together with the hypoxia condition that accelarates the secretion of growth factors, the repair of the damaged perioduntiom, including damaged bone, is initiated. If the precementum and cementoblast are injured, root resorption can occur.

CONCLUSIONS

Wound healing exhibits different patterns of action that involves immune stimulation in a bio-physiological activity, that occurs in the proper sequence, with overlapping phases. Two pathologic conditions, DAMPs and hypoxia, can activate the immune cells including clastic cells, eliminating damaged tissue and bone. Under certain conditions, root resorption occurs as a side effect.

Osteocyte RANKL Drives Bone Resorption in Mouse Ligature-Induced Periodontitis

Mouse ligature-induced periodontitis (LIP) has been used to study bone loss in periodontitis. However, the role of osteocytes in LIP remains unclear. Furthermore, there is no consensus on the choice of alveolar bone parameters and time points to evaluate LIP. Here, we investigated the dynamics of changes in osteoclastogenesis and bone volume (BV) loss in LIP over 14 days. Time-course analysis revealed that osteoclast induction peaked on days 3 and 5, followed by the peak of BV loss on day 7. Notably, BV was restored by day 14. The bone formation phase after the bone resorption phase was suggested to be responsible for the recovery of bone loss. Electron microscopy identified bacteria in the osteocyte lacunar space beyond the periodontal ligament (PDL) tissue. We investigated how osteocytes affect bone resorption of LIP and found that mice lacking receptor activator of NF-κB ligand (RANKL), predominantly in osteocytes, protected against bone loss in LIP, whereas recombination activating 1 (RAG1)-deficient mice failed to resist it. These results indicate that T/B cells are dispensable for osteoclast induction in LIP and that RANKL from osteocytes and mature osteoblasts regulates bone resorption by LIP. Remarkably, mice lacking the myeloid differentiation primary response gene 88 (MYD88) did not show protection against LIP-induced bone loss. Instead, osteocytic cells expressed nucleotide-binding oligomerization domain containing 1 (NOD1), and primary osteocytes induced significantly higher Rankl than primary osteoblasts when stimulated with a NOD1 agonist. Taken together, LIP induced both bone resorption and bone formation in a stage-dependent manner, suggesting that the selection of time points is critical for quantifying bone loss in mouse LIP. Pathogenetically, the current study suggests that bacterial activation of osteocytes via NOD1 is involved in the mechanism of osteoclastogenesis in LIP. The NOD1-RANKL axis in osteocytes may be a therapeutic target for bone resorption in periodontitis. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Periodontitis Disease in Farmed Ruminants-Current State of Research

Periodontal disease in ruminants is common and occurs in farmed and wild animals. Periodontal lesions can result from the secretion of endotoxins by pathogenic bacteria and as consequences of immune system activity. Three main types of periodontitis have been described. The first is chronic inflammation involving mainly premolars and molars-periodontitis (PD). The second type is an acute inflammatory reaction occurring with calcification of the periosteum of the jawbone and swelling of the surrounding soft tissues (Cara inchada, CI-"swollen face"). Finally, a third type, similar to the first but located in the incisor area, is called "broken mouth" (BM). Etiological variation between the different types of periodontitis is indicated. This particularly manifests in the composition of the microbiome, which is characteristic of the different forms of periodontitis. The widespread detection of lesions has drawn attention to the current nature of the problem.

Impact of Intermittent Fasting on Metabolic Syndrome and Periodontal Disease-A Suggested Preventive Strategy to Reduce the Public Health Burden

Metabolic syndrome (MetS) prevalence continues to climb significantly worldwide in today's ad libitum society. MetS has tremendous societal and economic ramifications, making it imperative to develop effective strategies for preventing and controlling it to alleviate this growing burden. Periodontal disease and MetS are associated with several risk factors. Studies in the past have demonstrated that obesity, cardiovascular illness, and type 2 diabetes mellitus have a negative effect on the severity of the periodontal disease. Patients with metabolic syndrome have elevated serum levels of proinflammatory mediators such as tumor necrosis factor-alpha interleukin-6 and C-reactive protein. Similar inflammatory mediators, such as interleukin-6, tumor necrosis factor-alpha, and C-reactive protein, are increased in patients with severe periodontal disease. Remarkably, intermittent fasting is underpinned by scientific evidence, claiming to be the most effective non-pharmacological, potential therapeutic alternative for combating a wide range of metabolic, inflammatory, and lifestyle-related diseases. Nonetheless, an insufficient investigation has been performed to determine whether intermittent fasting has therapeutic benefits on periodontal inflammation and diseases. Here, we show the interrelationship between metabolic syndrome and periodontal disease and contextualize the beneficial impact of intermittent fasting in modulating the chronic metabolic and periodontal inflammatory response. We also anticipate that this review paves the way for further exploration of intermittent fasting as a unique research paradigm representing a cost-effective alternative strategy to conventional disease management in patients with periodontal diseases and metabolic syndrome which may serve as the foundation for an integrative vision relevant to primary, diagnostic, and therapeutic purposes.

Human Cytomegalovirus Replication and Infection-Induced Syncytia Formation in Labial, Foreskin, and Fetal Lung Fibroblasts

Only a handful of cell types, including fibroblasts, epithelial, and endothelial cells, can support human cytomegalovirus (CMV) replication in vitro, in striking contrast to the situation in vivo. While the susceptibility of epithelial and endothelial cells to CMV infection is strongly modulated by their anatomical site of origin, multiple CMV strains have been successfully isolated and propagated on fibroblasts derived from different organs. As oral mucosal cells are likely involved in CMV acquisition, we sought to evaluate the ability of infant labial fibroblasts to support CMV replication, compared to that of commonly used foreskin and fetal lung fibroblasts. No differences were found in the proportion of cells initiating infection, or in the amounts of viral progeny produced after exposure to the fibroblast-adapted CMV strain AD169 or to the endothelial cell-adapted strain TB40/E. Syncytia formation was, however, significantly enhanced in infected labial and lung fibroblasts compared to foreskin-derived cells, and did not occur after infection with AD169. Together, these data indicate that fibroblast populations derived from different tissues are uniformly permissive to CMV infection but retain phenotypic differences of potential importance for infection-induced cell-cell fusion, and ensuing viral spread and pathogenesis in different organs.

Effects of cold physical plasma on oral lichen planus: An in vitro study (Effects of CAP on OLP)

OBJECTIVES

In the search for more effective and safe treatment avenues, we investigated cold physical plasma as a new treatment modality for therapy of oral lichen planus (OLP).

MATERIAL AND METHODS

Healthy and diseased human mucosal tissue samples with a size of 3 mm in diameter obtained from OLP patients were subjected to plasma treatment ex vivo or were left untreated. Tissue sections were quantified for immune-infiltration of CD4+ , CD8+ , CD45RA+ , and CD45R0+ T cells. Moreover, the tissues' inflammatory profile was assessed by analyzing 12 different cytokines in the surrounding media.

RESULTS

A significantly increased infiltrate of CD8+ and CD45-R0+ T cells was detected in OLP tissue samples when compared to healthy tissue. A higher concentration of interleukin (IL) 1β, IL6, IL8, and granulocyte macrophage-colony stimulating factor (GM-CMF) was detected in OLP samples compared to healthy mucosal tissue. For all cytokines and chemokines investigated, 23 out of 24 comparisons showed a decrease in tendency (significant for IL1β, IL2, IL10, and GM-CSF) in response to plasma treatment. In ex vivo-treated tissue, a decrease of T-cell infiltrate in OLP lesions compared with healthy tissue was observed.

CONCLUSION

Our findings suggest cold physical plasma can be a promising therapeutic option for OLP that requires further validation in vivo.

To evaluate the serum cortisol, salivary cortisol, and serum interleukin-1 B level in patients of chronic periodontitis with smoking and stress and without smoking and stress

The role of cognitive, social and biological factors in the etiology of chronic periodontitis has been reported.The aim of this study was to evaluate the salivary cortisol level and interleukin-1 B level in patients of Chronic periodontitis in smokers and stress and nonsmokers without stress.The design of study randomized, prospective, double-blinded, and prospective study.The total sample size was comprised of 600 subjects between the ages of 20 and 50 years. The sample size was divided into 300 males and 300 females. Out of 600 subjects, 200 subjects comprised of subjects with chronic periodontitis with positive depression level with a history of smoking (Group I), 200 subjects comprised of subjects with chronic periodontitis without depression and without smoking (Group II), and 200 subjects who were taken as the control group comprised of healthy subjects without chronic periodontitis, without depression level, and no smoking history (Group III). Salivary cortisol levels were determined by enzyme-linked immunosorbent assay (ELISA).The result showed that there was a positive correlation between morning and evening salivary cortisol level in all the groups with correlation coefficient. There was significant higher value of salivary cortisol in Group I patients when compared with Group II and Group III. However, when the comparison of salivary cortisol levels was done between the Group II and Control group, the result showed nonsignificant P value.It is suggested that stress is positively correlated with the salivary cortisol levels in smokers and nonsmokers.

Salivary Pro-Inflammatory Markers and Smoking Status Influences the Treatment Effectiveness of Periodontal Disease Patients with Hypertension

BACKGROUND

Hypertension and periodontal diseases share several risk factors. Inflammation biomarkers in saliva are related to hypertension and periodontal disease. The aim of this study was to explore the role of the salivary inflammatory biomarkers in the treatment effectiveness of patients with hypertension and periodontal disease.

METHODS

This observational study enrolled 160 subjects diagnosed with periodontitis, 40 of which had a history of hypertension. All subjects had completed scaling and root planning therapeutic procedures within four weeks. The clinical periodontal parameters (i.e., bleeding on probing, plaque control record (PCR), and probing depth (PD)) were evaluated before and after the treatment. Pro-inflammatory markers were determined using a commercial kit.

RESULTS

The recovery rate (PD 4-9 mm) in non-hypertensive subjects was significantly higher than in hypertensive subjects (60.47% vs. 52.60%, respectively; p = 0.04). All clinical parameters, excluding PCR, positively correlated with salivary IL-1β at baseline and after completing treatment. Our results showed that increased salivary IL-1β levels were positively associated with decreased PCR (β = -27.65 and p = 0.05) and PD recovery rate (β = -17.05 and p = 0.02) in hypertensive subjects.

CONCLUSIONS

The present study sheds important light on the clinical use of salivary pro-inflammatory cytokines as valuable biomarkers for predicting the treatment effectiveness of patients suffering from hypertension and periodontitis.

Systematic review of ratios between disease /health periodontitis modulators and meta-analysis of their levels in gingival tissue and biological fluids

OBJECTIVE

The ratio between molecules which acts towards the diseased or healthy phenotype determine whether the periodontitis lesions will progress or stabilize. Considering gingival tissue and biofluids, we aimed to present a systematic review (qualitative analysis) on the ratios between disease/health periodontitis modulators, and a meta-analysis (quantitative analysis) of their levels in individuals with periodontitis compared to controls.

DESIGN

Electronic searches of the PubMed, Scopus, EMBASE and Web of Science databases were conducted for publications up to May 2020.

RESULTS

A total of 53 publications were included in the systematic review, being 22 of them focusing on the ratios between Interleukin [IL]-1/IL-10, IL-6/IL-10, IL-1/IL-1RA and RANKL/OPG. Twenty-one publications were eligible for meta-analyses. The ratios of IL-1, IL-6 and RANKL mRNA levels were significantly higher in diseased gingival tissue, as well as their protein levels in gingival crevicular fluid (GCF) of periodontitis individuals. Considering the saliva levels, the RANKL/OPG ratio was higher in periodontitis subjects in comparison to controls. Meta-analyses showed higher IL-1β, IL-1α, IL-6 and IL-10 gene expressions in gingival tissue and protein levels in GCF, while RANKL was higher in GCF of periodontitis individuals in comparison to controls.

CONCLUSIONS

Both the ratios and meta-analyses showed higher levels of modulators in gingival tissue and GCF of diseased individuals.

An activated-zinc oral rinse reduces pro-inflammatory cytokine secretion and promotes proliferation in Porphyromonas gingivalis LPS-challenged gingival tissues - A pilot study

Objectives

The use of adjunct post‐treatment mouth rinses containing chlorhexidine (CHX) for periodontitis patients is associated with side effects that reduce patient compliance. Our aim was to evaluate the proinflammatory and cell proliferation effects of an activated‐zinc mouth rinse (SM) that has been suggested as an alternative post‐treatment therapeutic.

Materials and Methods

Tissue models of gingival epithelium were used to simulate periodontal disease and compare inflammatory reactions after treatment with CHX or SM. Tissues were exposed to Porphyromonas gingivalis LPS and wounded to simulate periodontal disease. Tissues were treated and incubated for 6, 12, or 24 h. Inflammatory cytokines were measured in culture medium by ELISA and local expression of Toll‐like receptor (TLR)‐4 and proliferation marker Ki‐67 was visualized by immunohistochemistry.

Results

SM and CHX treatments decreased secretion of IL‐1β and IL‐8 into culture media at all time points. IL‐1β secretion levels were further decreased by SM compared to CHX treatment at all time points. TLR‐4 expression appeared significantly increased 12 h post‐treatment in the CHX tissues but remained relatively low in SM tissues at all time points. Ki‐67 results suggest that cell proliferation was increased in the SM tissues earlier than CHX tissues.

Conclusions

Our data suggest that SM may reduce inflammation in gingival tissues.

IL-1B(3954) polymorphism and red complex bacteria increase IL-1β (GCF) levels in periodontitis

OBJECTIVE

The aim of this study was to compare IL-1β levels in gingival crevicular fluid (GCF) from healthy and periodontitis sites of IL-1B(3954)-Single Nucleotide Polymorphism (SNP) positive and IL-1B(3954)-SNP negative periodontitis subjects in association with their bacterial profiles.

BACKGROUND

Susceptibility to periodontitis has been associated with several risk factors, including allelic variants at multiple gene loci. Variations in the IL-1 gene cluster have been linked with increased risk for periodontitis. IL-1B(3954)-SNP has been previously associated with increased levels of IL-1β in GCF or periodontal tissues in chronic periodontitis patients, as well as higher levels of specific periodontal pathogens. There is insufficient evidence to conclude if IL-1B gene polymorphisms affect the susceptibility to periodontitis by ultimately modulating the levels of IL-1β in GCF, the subgingival microbial profile or both.

MATERIALS AND METHODS

GCF, subgingival plaque, and buccal epithelial cells were collected from 32 individuals with periodontitis. GCF IL-1β levels were measured by an enzyme-linked immunosorbent assay (ELISA). Bacterial plaque samples were analyzed for 11 periodontal pathogens using polymerase chain reaction (PCR) analysis with specific primers for the 16SrRNA gene of each bacterium. IL-1B(3954)-SNP status was determined by identifying the carriers of the polymorphic T allele.

RESULTS

A significant association was shown between IL-1B(3954)-SNP and IL-1β GCF levels (amount and concentration). The concomitant presence of two or three red complex bacterial species was associated with increased IL-1β GCF levels in periodontitis sites (site-level analysis). The concurrent presence of all three red complex periodontal pathogens and IL-1B(3954)-SNP was associated with the highest IL-1β GCF levels in periodontitis sites.

CONCLUSIONS

Our results indicate an independent association of both IL-1B(3954)-SNP and red complex bacterial species with increased IL-1β levels in GCF of periodontitis sites. A better understanding of the interaction between genetics, bacteria, and inflammation is essential to develop more effective diagnostic, prognostic, and therapeutic tools for periodontitis.

Tricarbonyldichlororuthenium(II) dimer, the lipid-soluble carbon monoxide-releasing molecule, attenuates Prevotella intermedia lipopolysaccharide-induced production of nitric oxide and interleukin-1β in murine macrophages

Carbon monoxide (CO) is increasingly being appreciated as an important mediator that has pleiotropic biological properties and appears to have a possible therapeutic application for a variety of disorders. Nevertheless, whether this gaseous molecule may be utilized as a therapeutic intervention for periodontal disease is unclear. Here, we examined the potential beneficial effect of CO-releasing molecule-2 (CORM-2), a tricarbonyldichlororuthenium(II) dimer, against the elaboration of proinflammatory mediators by murine macrophages challenged with lipopolysaccharide (LPS) isolated from Prevotella intermedia, a pathogenic bacterium implicated in inflammatory periodontal disease. We found that NO and IL-1β production, iNOS protein expression and mRNA expressions of iNOS and IL-1β were significantly down-regulated when LPS-challenged RAW264.7 cells were exposed to CORM-2. In addition, HO-1 expression was upregulated by CORM-2 in cells activated with P. intermedia LPS, and the inhibitory influence of CORM-2 upon NO production was attenuated by tin protoporphyrin IX, an inhibitor of HO activity. PPAR-γ did not function in the attenuation of NO and IL-1β by CORM-2. JNK and p38 phosphorylation caused by LPS was not altered by CORM-2. CORM-2 reduced NF-κB reporter activity and IκB-α degradation elicited by P. intermedia LPS. Additionally, CORM-2 inhibited LPS-induced phosphorylation of STAT1/3. In conclusion, CORM-2 suppresses NO and IL-1β production caused by P. intermedia LPS. CORM-2 exerts its effect by a mechanism involving anti-inflammatory HO-1 induction and attenuation of NF-κB and STAT1/3 activation, independently of PPAR-γ as well as JNK and p38. CORM-2 may hold promise as host response modulation agent for periodontal disease, though further research is indicated to verify the therapeutic effect.

IL-1β strengthens the physical barrier in gingival epithelial cells

Periodontitis is one of the most common oral diseases worldwide and is caused by a variety of interactions between oral bacteria and the host. Here, pathogens induce inflammatory host responses that cause the secretion of proinflammatory cytokines such as IL-1β, IL-6, and IL-8 by oral epithelial cells. In various systems, it has been shown that inflammation compromises physical barriers, which enables bacteria to invade the tissue. In this study, we investigated the barrier properties of the oral mucosa under physiological and inflamed conditions. For this purpose, we assessed the influence of IL-1β on the transepithelial electrical resistance and in particular on tight junctions in vitro in human stratified squamous epithelium models. Indirect immunofluorescence and western blot analyses were performed to investigate localization and expression of tight junction proteins in primary gingival cells, immortalized gingival cells and native gingiva. Furthermore, the TEER of gingival keratinocytes was assessed. The results showed that IL-1β led to strengthening of the gingival keratinocyte barrier. This was demonstrated by an increase in TEER, the upregulation of TJ proteins, and an increase in the formation of TJ strands. The IL-1β-mediated upregulation of occludin was prevented by the NF-κB inhibitor BAY 11-7085. These observations provide insights into host responses in the early stages of periodontal disease and offer information about TJ formation in human gingival epithelial cells under physiological and inflammatory conditions. Comprehensive knowledge of the physical barrier during inflammation may help in developing strategies to effectively target the inflammatory barrier to improve the bioavailability of drugs for the treatment of periodontitis.

Systemic expression of genes related to inflammation and lipid metabolism in patients with dyslipidemia, type 2 diabetes mellitus and chronic periodontitis

Inflammatory diseases, as periodontal disease (PD), has been associated with disturbance of lipid and glycemic metabolisms, as demonstrated by the increasing of PD patients with type 2 diabetes mellitus (T2D) and/or dyslipidemia comorbidities. We aimed to investigate the expression of inflammation and lipid metabolism genes, and correlations among clinical and biochemical characteristics in normoglycemic or T2D patients with dyslipidemia and PD, in comparison with healthy individuals. Five groups of 30 individuals each (150 patients) were formed based upon T2D, dyslipidemic and periodontal status. Blood analyses of lipid and glycemic profiles were carried out, and the gene expression was assessed by RT-qPCR. The systemic expression of IL6, TNFA and LEP genes were significantly higher in T2D, dyslipidemia and PD patients, while the PECAM1 gene showed the opposite. Higher RETN levels were found in patients with T2D independently of their glycemic control status. There were positive correlations between: TNFA, LEP and RETN with worse periodontal parameters; IL6, TNFA, ADIPOR1, LEP and RETN with waist-to-hip ratio; glycemic parameters with RETN; total cholesterol and triglycerides with LEP expression. We conclude that pro-inflammatory cytokines were related with worse lipid, glycemic and periodontal parameters, reinforcing that a hyper-inflammatory status connects systemic and oral inflammatory diseases.

Immunomodulatory factors gene polymorphisms in chronic periodontitis: an overview

BACKGROUND

Chronic periodontitis (CP), defines as destruction of the supporting tissues of the teeth and resorption of the alveolar bone. It is widespread in human populations and represent an important problem for public health. CP results from inflammatory mechanisms created by the interaction between environmental and host genetic factors that confer the individual susceptibility to the disease.

AIM

The aim of the current study was to explore and summarize some functional biomarkers that are associated with CP susceptibility.

METHODS

CP is considered to be a multifactorial disease. The pathogenesis of multifactorial diseases is characterized by various biological pathways. The studies revealed that polymorphisms were associated with susceptibility to periodontal diseases. In other word, genetic variations can change the development of CP. However, there are some conflicting results, because there are different variations in frequency of some alleles in any populations. Therefore, we conducted the current review to completely understanding the special biomarkers for CP.

RESULTS

There is some evidence that SNPs in the IL-1α, IL-1β, IL1RN, IL-6, IL-10, TNF-α, TGF-β1, IFN-γ and VDR may be associated with CP susceptibility.

CONCLUSION

In conclusion, numerous studies have reported the host genetic factors associated with CP susceptibility and related traits. Therefore, it is prevail to study the multiple SNPs and their effects to find the useful diagnosis methods. The current study will investigate the relationship between polymorphisms in cytokine genes and the susceptibility to the chronic periodontitis.

The depth of the implant mucosal tunnel modifies the development and resolution of experimental peri-implant mucositis: A case-control study

Background

Resolution and prevention of peri‐implant mucositis are a key in preventing peri‐implantitis. This case–control study aims to assess the modifying effect of a deep mucosal tunnel (DMT) on the induction and resolution phases of experimental peri‐implant mucositis.

Methods

Nineteen subjects with a tissue level implant were assigned to cases (DMT, depth ≥3 mm) or controls (shallow mucosal tunnel ≤1 mm, SMT). Subjects underwent a standard experimental peri‐implant mucositis protocol characterized by an oral hygiene optimization phase, a 3‐week induction phase using an acrylic stent to prevent self‐performed oral hygiene at the experimental implant, and a 3 + 2 weeks resolution phase. Modified plaque (mPI), gingival index (mGI) and peri‐implant sulcus fluid IL‐1β concentrations were measured over time. Differences between DMT and SMT were assessed with the Mann–Whitney test.

Results

Modified plaque index and mGI increased in parallel during the induction phase. After resumption of oral hygiene practice, mPI and mGI resolved towards baseline values in the SMT group. In DMT, mPI and mGI values diverged: plaque resolved but resolution of inflammation was delayed and of smaller magnitude during the first 3 weeks after resumption of oral hygiene. IL‐1β concentrations were significantly higher in DMT at 21 days (end of induction) and during the resolution phase corroborating the clinical findings. Removal of the crown and submucosal professional cleaning were needed to revert mGI to baseline values in DMT implants.

Conclusions

The depth of the mucosal tunnel modifies the resolution of experimental peri‐implant mucositis at transmucosal implants. This observation raises important questions on the effectiveness of self‐performed oral hygiene in cases where implants are placed deeper and the ability to resolve mucositis and effectively prevent peri‐implantitis in such situations.

Periodontal, metabolic, and cardiovascular disease: Exploring the role of inflammation and mental health

Previous evidence connects periodontal disease, a modifiable condition affecting a majority of Americans, with metabolic and cardiovascular morbidity and mortality. This review focuses on the likely mediation of these associations by immune activation and their potential interactions with mental illness. Future longitudinal, and ideally interventional studies, should focus on reciprocal interactions and cascading effects, as well as points for effective preventative and therapeutic interventions across diagnostic domains to reduce morbidity, mortality and improve quality of life.

Periodontal reconstruction by heparan sulfate mimetic-based matrix therapy in Porphyromonas gingivalis-infected mice

BACKGROUND

Periodontitis is a set of chronic inflammatory diseases affecting the supporting structures of the teeth, during which a persistent release of lytic enzymes and inflammatory mediators causes a self-perpetuating vicious cycle of tissue destruction and repair. A matrix-based therapy using a heparan sulfate (HS) analogue called ReGeneraTing Agent (RGTA) replaces destroyed HS by binding to available heparin-binding sites of structural molecules, leading to restoration of tissue homeostasis in several inflammatory tissue injuries, including a hamster periodontitis model.

METHODS

The ability of RGTA to restore the periodontium was tested in a model of Porphyromonas gingivalis-infected Balb/cByJ mice. After 12 weeks of disease induction, mice were treated weekly with saline or RGTA (1.5 mg/kg) for 8 weeks. Data were analyzed by histomorphometry.

RESULTS

RGTA treatment restored macroscopic bone loss. This was related to (1) a significant reduction in gingival inflammation assessed by a decrease in infiltrated connective tissue, particularly in cells expressing interleukin 1ß, an inflammatory mediator selected as a marker of inflammation; (2) a normalization of bone resorption parameters, i.e. number, activation and activity of osteoclasts, and number of preosteoclasts; (3) a powerful bone formation reaction. The Sharpey's fibers of the periodontal ligament recovered their alkaline phosphatase coating. This was obtained while P. gingivalis infection was maintained throughout the treatment period.

CONCLUSIONS

RGTA treatment was able to control the chronic inflammation characteristic of periodontitis and blocked destruction of periodontal structures. It ensured tissue regeneration with recovery of the periodontium's anatomy.

Clinical and Radiographic Peri-Implant Parameters and Whole Salivary Interleukin-1β and Interleukin-6 Levels among Type-2 Diabetic and Nondiabetic Patients with and without Peri-Implantitis

OBJECTIVE

The aim was to assess the peri-implant clinical and radiographic parameters and whole salivary levels of interleukin (IL)-1β and IL-6 among type 2 diabetic and nondiabetic patients with and without peri-implantitis.

MATERIAL AND METHODS

Ninety-one implants were placed in patients without type 2 diabetes mellitus (39 patients with and 52 patients without peri-implantitis; group 1). Eighty implants were placed in patients with diabetes (35 patients with and 45 patients without peri-implantitis; group 2). Peri-implant plaque index, bleeding on probing, probing depth, and marginal bone loss were measured. Unstimulated whole saliva samples were collected and IL-1β and IL-6 levels were measured using standard techniques. p < 0.05 was considered statistically significant.

RESULTS

In group 1, plaque index (p < 0.001), bleeding on probing (p < 0.001), probing depth (p < 0.001), and whole salivary IL-1β (p < 0.001) and IL-6 (p < 0.001) levels were significantly higher in patients with peri-implantitis than in those without peri-implantitis. Plaque index, bleeding on probing, probing depth, and marginal bone loss were comparable among all of the patients in group 2. Among patients with peri-implantitis, plaque index (p < 0.001), bleeding on probing (p < 0.001), probing depth (p < 0.001), marginal bone loss (p < 0.001), and whole salivary IL-1β (p < 0.001) and IL-6 (p < 0.001) levels were significantly higher in those with diabetes than in those without diabetes.

CONCLUSION

Among individuals without diabetes, peri-implant plaque index, bleeding on probing, probing depth, marginal bone loss, and whole salivary IL-1 β and IL-6 levels were higher among patients with peri-implantitis compared to patients without peri-implantitis. Among patients with diabetes, the severity of the measured parameters appears to be influenced by the glycemic status rather than by peri-implantitis.

Inflammasome and Oral Diseases

One of the main steps in the development of the life in the earth is multicellularity. It enables cell differentiation and the development of morphological structures within an organism and is an essential factor in how to recognize friendly cells that are part of the multicellular organism and which foreign organisms can be harmful. Recognition includes devices such as the major histocompatibility complex (MHC), and the pattern recognition receptors (PRRs). PRRs are a group of proteins expressed by cells of the innate immune system that identify two classes of products: pathogen-associated molecular patterns (PAMPs), related to microbial pathogens, and damage-associated molecular patterns (DAMPs), associated with cell components that are released during cell damage or death. All these activate the inflammasome, which is a multiprotein oligomer that includes caspase 1, PYCARD, NALP, and caspase 5 (also known as caspase 11 or ICH-3). It is responsible for activation of inflammatory processes and has been shown to induce cell pyroptosis, a programmed cell death distinct from apoptosis, and promotes the maturation of the inflammatory cytokines interleukin 1β (IL-1β) and interleukin 18 (IL-18). We review whether inflammasome is related to diseases that can occur in the oral cavity. The mouth is always a possible environment for the development of pathological conditions because of the wide variety of microorganisms. Small variations in the equilibrium of the oral flora can cause disorders that could affect the organism in a systemic form. We provide data on periodontal disease, candidiasis, herpes virus, oral cancer, caries, and other oral diseases. There are very few papers that study this issue; therefore, we need more investigation and publications about inflammatory molecular processes, and more specifically, related to the inflammasome complex.

Ultrasound microbubble-mediated transfection of NF-κB decoy oligodeoxynucleotide into gingival tissues inhibits periodontitis in rats in vivo

Periodontitis is a chronic infectious disease for which the fundamental treatment is to reduce the load of subgingival pathogenic bacteria by debridement. However, previous investigators attempted to implement a nuclear factor kappa B (NF-κB) decoy oligodeoxynucleotide (ODN) as a suppressor of periodontitis progression. Although we recently reported the effectiveness of the ultrasound-microbubble method as a tool for transfecting the NF-κB decoy ODN into healthy rodent gingival tissue, this technique has not yet been applied to the pathological gingiva of periodontitis animal models. Therefore, the aim of this study was to investigate the effectiveness of the technique in transfecting the NF-κB decoy ODN into rats with ligature-induced periodontitis. Micro computed tomography (micro-CT) analysis demonstrated a significant reduction in alveolar bone loss following treatment with the NF-κB decoy ODN in the experimental group. RT-PCR showed that NF-κB decoy ODN treatment resulted in significantly reduced expression of inflammatory cytokine transcripts within rat gingival tissues. Thus, we established a transcutaneous transfection model of NF-κB decoy ODN treatment of periodontal tissues using the ultrasound-microbubble technique. Our findings suggest that the NF-κB decoy ODN could be used as a significant suppressor of gingival inflammation and periodontal disease progression.

Comparison of Clinical, Radiographic, and Immunologic Inflammatory Parameters around Crestally and Subcrestally Placed Dental Implants: 5-Year Retrospective Results

PURPOSE

To compare changes in clinical (bleeding on probing [BOP] and probing pocket depth [PPD]), radiographic (crestal bone loss [CBL]), and immunologic inflammatory (interleukin-1beta [IL-1β] and matrix metalloproteinase-9 [MMP-9]) parameters around crestally and subcrestally placed dental implants 5 years after implant placement.

MATERIALS AND METHODS

Fifty-two patients were divided into 2 groups: group 1 (n = 27): patients with single implants placed approximately 2 mm below the alveolar crest; group 2 (n = 25): patients with single implants placed at bone level. In both groups, peri-implant BOP, PPD, and CBL were measured, and levels of IL-1β and MMP-9 were determined in duplicates using enzyme-linked immunosorbent assay. Full-mouth debridement was performed biannually in both groups. Statistical analysis was performed using the Mann-Whitney U test (significance set at p < 0.05).

RESULTS

All measurements in groups 1 and 2 were performed 5.3 ± 0.2 and 5.2 ± 0.1 years after implant placement, respectively. The mean CBL was 1.2 ± 0.2 mm and 1.4 ± 0.2 mm in groups 1 and 2, respectively. There was no significant difference in mean BOP, PPD, CBL and in levels of IL-1β, and MMP-9 among implants in both groups.

CONCLUSION

Clinical, radiographic, and immunologic inflammatory parameters are comparable around crestally and subcrestally placed single dental implants up to 5 years after placement. The depth of implant placement appears to have no effect on clinical status and performance of single dental implants.

A new approach to transfect NF-κB decoy oligodeoxynucleotides into the periodontal tissue using the ultrasound-microbubble method

The objective of this study is to investigate the effect of the ultrasound-microbubble technique in nuclear factor kappa B (NF-κB) decoy oligodeoxynucleotide (ODN) transfection in the gingival tissue in mice. The 6-FAM-labeled scrambled decoy ODN with microbubbles was applied to the periodontal tissue in 8-week-old male C57BL/6J mice by ultrasound radiation at low (LUM-Sc) and high (HUM-Sc) intensities to optimize the transfection condition of the ultrasound-microbubble method. Histological inspections were performed two hours after transfection to compare the expression with that in the sham-operated group without ultrasound radiation (A-Sc). Then, an NF-κB decoy was transfected into the periodontal tissue using the high-intensity ultrasound-microbubble (HUM-NF) technique to examine the anti-inflammatory effects of the decoy ODN. Western blot analysis was performed to investigate the expression of interleukin(IL)-1β, IL-6 and intercellular adhesion molecule-1 (ICAM-1) in the gingival tissues in the HUM-Sc, the HUM-NF and control groups. The fluorescence microscopy results showed that the fluorescent intensity in the periodontal tissues in the LUM-Sc and HUM-Sc groups was significantly higher than that in the A-Sc and the control groups. The fluorescent intensity in the HUM-Sc group, especially in the gingival connective tissue, was the highest of all groups. Western blot analysis indicated that the protein expression levels of IL-1β, IL-6 and ICAM-1 in the HUM-NF group were significantly lower than those in the HUM-Sc and the control groups. These findings suggest that the high-intensity ultrasound-microbubble technique is an effective tool for decoy transfection into the periodontal tissue.

Human β-defensin-2 and interleukin-1β expression in response to Porphyromonas gingivalis challenge in mice transplanted with periodontitic human gingiva

Inter-individual variability in the host response contributes significantly to expression of periodontal disease. Thus, research into the human host response is considered important in the analysis of periodontal disease. Human β-defensin-2 (hBD-2) is typically produced by epithelial tissues after stimulation with microorganisms and inflammatory mediators, and it contributes to the initial defense in the innate immune response. However, hBD-2 expression in response to infection has not been investigated in human gingival tissue with periodontitis. We examined the response to Porphyromonas gingivalis in an established in vivo model of human gingival grafts with various degrees of periodontitis. We also investigated the expression profile of interleukin-1β (IL-1β). Gingival tissues were collected from 40 patients with chronic periodontitis (21 with slight-to-moderate disease, 19 with severe disease) during tooth extraction or periodontal surgery. These tissues were transplanted subcutaneously into nu/nu mice. We used real-time PCR to compare the expression of hBD-2 and IL-1β. In slight-to-moderate chronic periodontitis, hBD-2 expression was significantly higher in the stimulated group than in the non-stimulated group (p < 0.05), but there was no significant increase in the group with severe chronic periodontitis. IL-1β expression did not differ between groups. Increased expression of hBD-2 and IL-1β was associated with slight-to-moderate periodontitis (p < 0.05), and there was a significant relationship between decreased hBD-2 and IL-1β expression and severe periodontitis (p < 0.05). The initial expression profile of hBD-2 in P. gingivalis infection differs according to the severity of periodontitis. In addition, changes in hBD-2 and IL-1β expression may be important in the progression of periodontitis.

Effect of scaling and root planing with and without adjunct use of an essential-oil-based mouthwash on whole salivary interleukin-1β levels in patients with periodontal disease: A short-term follow-up study

OBJECTIVE

The aim of the present short-term follow-up study was to assess the effect of scaling and root planing (SRP) with and without adjunct use of an essential-oil-based mouthwash (EOBM) on whole salivary interleukin (IL)-1beta (β) levels in patients with periodontal disease.

METHODS

Ninety individuals with periodontal disease were divided into two groups. Patients in group 1 underwent SRP and were instructed to rinse with 10 mL of an EOBM twice daily for 30 days. Patients in group 2 underwent SRP and were instructed to rinse with 10 mL of water twice daily for 30 days. Whole saliva samples were collected, and IL-1β levels were measured at baseline and after 60 days of treatment. P-values < 0.05 were considered statistically significant.

RESULTS

At baseline, whole salivary IL-1β levels were comparable among patients in groups 1 (135.6 ± 13.5 μg/mL) and 2 (141.2 ± 5.4 μg/mL). After 60 days of follow-up, there is a significant decrease in whole salivary IL-1β levels among patients in group 1 (10.2 ± 6.4 μg/mL) as compared to those in group 2 (56.6 ± 10.2 μg/mL) (P < 0.01).

CONCLUSION

SRP, when performed with adjunct use of an EOBM, is more effective in reducing whole salivary IL-1β levels as compared to when SRP is performed without the use of an EOBM.

Epithelial barrier and oral bacterial infection

The oral epithelial barrier separates the host from the environment and provides the first line of defense against pathogens, exogenous substances and mechanical stress. It consists of underlying connective tissue and a stratified keratinized epithelium with a basement membrane, whose cells undergo terminal differentiation resulting in the formation of a mechanically resistant surface. Gingival keratinocytes are connected by various transmembrane proteins, such as tight junctions, adherens junctions and gap junctions, each of which has a specialized structure and specific functions. Periodontal pathogens are able to induce inflammatory responses that lead to attachment loss and periodontal destruction. A number of studies have demonstrated that the characteristics of pathogenic oral bacteria influence the expression and structural integrity of different cell-cell junctions. Tissue destruction can be mediated by host cells following stimulation with cytokines and bacterial products. Keratinocytes, the main cell type in gingival epithelial tissues, express a variety of proinflammatory cytokines and chemokines, including interleukin-1alpha, interleukin-1beta, interleukin-6, interleukin-8 and tumor necrosis factor-alpha. Furthermore, the inflammatory mediators that may be secreted by oral keratinocytes are vascular endothelial growth factor, prostaglandin E2 , interleukin-1 receptor antagonist and chemokine (C-C motif) ligand 2. The protein family of matrix metalloproteinases is able to degrade all types of extracellular matrix protein, and can process a number of bioactive molecules. Matrix metalloproteinase activities under inflammatory conditions are mostly deregulated and often increased, and those mainly relevant in periodontal disease are matrix metalloproteinases 1, 2, 3, 8, 9, 13 and 24. Viral infection may also influence the epithelial barrier. Studies show that the expression of HIV proteins in the mucosal epithelium is correlated with the disruption of epithelial tight junctions, suggesting a possible enhancement of human papilloma virus infection by HIV-associated disruption of tight junctions. Altered expression of matrix metalloproteinases was demonstrated in keratinocytes transformed with human papilloma virus-16 or papilloma virus-18,. To summarize, the oral epithelium is able to react to a variety of exogenous, possibly noxious influences.

Oral Epithelial Overexpression of IL-1α Causes Periodontal Disease

Periodontal disease is a bacterial infection that results in inflammatory destruction of tissues that support the teeth, including connective tissue and bone. In this study, we report that transgenic mice that overexpress the 17-kDa form of IL-1α in the basal layer of oral mucosal epithelium develop a syndrome that possesses all of the cardinal features of periodontal disease, including epithelial proliferation and apical migration, loss of attachment, and destruction of cementum and alveolar bone. In this model, bacterial colonization and infection were not required, since levels of periodontal bacteria were equivalent in transgenic and wild-type mice, and continuous treatment with antibiotics from birth did not ameliorate the disease. Our findings therefore indicate that elevated levels of IL-1α in the oral micro-environment can mediate all of the clinical features of periodontal disease.

Investigating the Effects of Systemically Administered Strontium Ranelate on Alveolar Bone Loss Histomorphometrically and Histopathologically on Experimental Periodontitis in Rats

BACKGROUND

The aim of this study is to investigate effects of strontium ranelate (SR) on alveolar bone loss (ABL) in rats with experimental periodontitis.

METHODS

Forty Wistar rats were randomly divided into five groups: 1) control (n = 8); 2) ligated (n = 8); 3) 300 mg/kg SR (SR300, n = 8); 4) 625 mg/kg SR (SR625, n = 8); and 5) 900 mg/kg SR (SR900, n = 8). To create experimental periodontitis, 4/0 silk ligatures were inserted submarginally around first molars at the right mandible. After 11 days, rats were sacrificed. ABL was calculated by measuring cemento-enamel junction and alveolar crest distance. Interleukin (IL)-1β, osteoprotegerin (OPG), and bone-specific alkaline phosphatase (BALP) serum levels were determined by enzyme-linked immunosorbent assay. Histopathologic analysis was used to evaluate inflammatory cell infiltration, numbers of osteoblasts and osteoclasts, and receptor activator of nuclear factor-kappa B ligand (RANKL) activity.

RESULTS

ABL was significantly lower in SR900 group than in the ligated group (P <0.05). Osteoclast numbers in ligated group were significantly higher than in the control, SR300, and SR900 groups (P <0.05). In ligated, SR625, and SR900 groups, significantly higher osteoblast numbers were detected than in control group (P <0.05). Osteoblast numbers in SR625 group were significantly higher than in the SR300 group (P <0.05). RANKL activities in SR900 and control groups were close to each other (P >0.05). Serum IL-1β, OPG, and BALP levels revealed no significant difference (P >0.05).

CONCLUSION

It can be concluded that SR can reduce RANKL activity and osteoclast numbers, as well as ABL.

Pro-atherogenic properties of lipopolysaccharide from the periodontal pathogen Actinobacillus actinomycetemcomitans

An association between cardiovascular and periodontal disease may be due to lipopolysaccharide (LPS)-promoted release of inflammatory mediators, adverse alterations of the lipoprotein profile, and an imbalance in cholesterol homeostasis. Since periodontopathogenic potential differs between serotypes of a major periodontal pathogen, Actinobacillus actinomycetemcomitans, we studied the pro-atherogenic properties of LPS preparations from serotypes b and d strains on macrophages (RAW 264.7). A. actinomycetemcomitans LPS preparations induced a time-dependent release of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). LPS induced foam cell formation and cholesteryl ester accumulation from native low density lipoprotein in the following order: A. actinomycetemcomitans strains JP2 (serotype b) > Y4 (serotype b) > IDH781 (serotype d). mRNA expression levels of scavenger receptor class B, type-I, and ATP-binding cassette transporter-1, receptors mediating cholesterol efflux from macrophages, were decreased by LPS preparations. The results suggest that the pro-atherogenic potential of A. actinomycetemcomitans LPS may depend on the infecting strain and correlate with the periodontopathogenic potential of the pathogen.

Interleukin 1β (+3954, -511 and -31) polymorphism in chronic periodontitis patients from North India

OBJECTIVE

Several studies have implicated the role of interleukin-1 in various chronic diseases including periodontitis. The present study was carried out with an aim to evaluate the role of interleukin 1β polymorphisms, namely +3954C/T, -511C/T and -31T/C, in the development of chronic periodontitis.

MATERIALS AND METHODS

Twenty-nine chronic periodontitis patients and 31 healthy controls of North Indian origin from Chhattisgarh were recruited for the study. The genotypes for the three variants were determined using the PCR-RFLP technique and the strength of association between genotypes and periodontitis was determined by odds ratio with 95% confidence interval (CI) and chi-square analysis.

RESULTS

Analysis for the +3954 allelic and genotypic frequencies of the polymorphism revealed a significant difference in the CT genotype between periodontitits patients and controls (p = 0.03). A significant difference was also observed in the allelic frequencies between the two groups (p = 0.02). For the -511 site, TT genotype revealed a significant association with the disease (p = 0.01). A significant association was also found following the co-dominant model (p = 0.007). However, the -31 polymorphism revealed no significant difference between patients and controls.

CONCLUSIONS

In conclusion, the present study suggests a strong association of the TT genotype of -511 and CT genotype of +3954 variant of interleukin 1β with chronic periodontitis. However, the -31 variant did not show a significant association with the disease.

Study of the association between the interleukin-1 β c.3954C>T polymorphism and periodontitis in a population sample from Bahia, Brazil

BACKGROUND

Periodontitis is an inflammatory disease characterized by the loss of connective tissue and alveolar bone. Different factors are associated with the onset and prognosis of this disease, both environmental and genetic. The latter particularly relate to molecules secreted as a function of the host immune response, such as pro-inflammatory cytokines. Studies indicate that the polymorphism c. 3954C > T in the interleukin-1 β encoding gene (IL1B) can be considered as an aggravating factor in the periodontitis condition.

AIMS

This study aimed to evaluate whether there is an association between the IL1B c. 3954C > T gene polymorphism and the prevalence of periodontitis in the population from Vitória da Conquista-Bahia, Brazil.

MATERIALS AND METHODS

A total of 347 subjects (134 cases and 213 controls) who provided epithelial tissue of the oral cavity and saliva samples for DNA extraction and quantification of IL1B, respectively, were selected. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism followed by electrophoresis in agarose gel. The evaluation of the cytokine concentration was performed by enzyme-linked immunosorbent assay.

STATISTICAL ANALYSIS

Statistical calculations involved in this work include Chi-square test, Fisher Exact test, Mann-Whitney and Kruskal-Wallis tests.

RESULTS

Our findings revealed that: (i) No statistically significant relationship between periodontitis and the polymorphism studied was observed; (ii) no significant difference between the concentrations of IL1B in saliva between the case and control subjects and between the genotypes of these individuals and the concentrations of this cytokine.

CONCLUSIONS

We conclude that, in the sample evaluated, the IL1B c. 3954C > T polymorphism did not present as an etiological factor for periodontitis.

Cell adhesion proteins: roles in periodontal physiology and discovery by proteomics

Adhesion molecules expressed by periodontal connective tissue cells are involved in cell migration, matrix remodeling and inflammatory responses to infection. Currently, the processes by which the biologic activity of these molecules are appropriately regulated in time and space to preserve tissue homeostasis, and to control inflammatory responses and tissue regeneration, are not defined. As cell adhesions are heterogeneous, dynamic, contain a complex group of interacting molecules and are strongly influenced by the type of substrate to which they adhere, we focus on how cell adhesions in periodontal connective tissues contribute to information generation and processing that regulate periodontal structure and function. We also consider how proteomic methods can be applied to discover novel cell-adhesion proteins that could potentially contribute to the form and function of periodontal tissues.

Piperine inhibit inflammation, alveolar bone loss and collagen fibers breakdown in a rat periodontitis model

BACKGROUND AND OBJECTIVE

Piperine exhibits anti-inflammatory activity, and has a long history of medicinal use. The objective of this study was to investigate the protective effects of piperine on inflammation, alveolar bone and collagen fibers in experimental periodontitis. We evaluated the related expression of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, matrix metalloproteinase (MMP)-8 and MMP-13 to enhance insight into these effects.

MATERIAL AND METHODS

Thirty-two Wistar rats were divided into four groups of eight animals each: control group, periodontitis group, periodontitis plus 50 mg/kg piperine group and periodontitis plus 100 mg/kg piperine group. Histopathologic changes were detected by hematoxylin and eosin staining. Alveolar bone loss and trabecula microstructures were evaluated by micro-computed tomography. Changes in collagen fibers were assessed by picrosirius red staining. Western blot analysis was conducted to determine the levels of IL-1β, TNF-α, MMP-8 and MMP-13.

RESULTS

Piperine clearly inhibited alveolar bone loss and reformed trabecula microstructures in a dose-dependent manner. Histological staining showed that piperine significantly reduced the infiltration of inflammation in soft tissues. Both doses of piperine limited the fractions of degraded areas in collagen fibers. Piperine (100 mg/kg) significantly downregulated the expressions of IL-1β, MMP-8 and MMP-13 in periodontitis, but not that of TNF-α.

CONCLUSION

Piperine displays significantly protective effects on inflammation, alveolar bone loss, bone microstructures and collagen fiber degradation in experimental periodontitis. The effects may be ascribed to its inhibitory activity on the expressions of IL-1β, MMP-8 and MMP-13.

Periodontal Status and Whole Salivary Cytokine Profile Among Smokers and Never-Smokers With and Without Prediabetes

BACKGROUND

Whole salivary interleukin (IL)-1β and IL-6 in smokers and never-smokers with prediabetes remains uninvestigated. The aim of this study is to assess the periodontal status and whole salivary IL-1β and IL-6 levels among smokers and never-smokers with and without prediabetes (controls).

METHODS

Ninety-five males (45 with prediabetes and 50 systemically healthy controls) were included. Twenty-seven controls and 29 patients with prediabetes were smokers. Periodontal parameters (plaque index, bleeding on probing, probing depth, clinical attachment loss, and marginal bone loss) were measured, and the number of missing teeth were recorded. Fasting blood glucose (FBG) and hemoglobin A1c (HbA1c) levels were recorded. Unstimulated whole saliva samples were collected, unstimulated whole salivary flow rate (UWSFR) was determined, and IL-1β and IL-6 levels were measured. P values <0.05 were considered statistically significant.

RESULTS

FBG (P <0.05) and HbA1c (P <0.05) levels were higher among patients with prediabetes than controls. All patients with prediabetes were hyperglycemic. UWSFR was significantly higher among controls than among patients with prediabetes (P <0.05). Periodontal parameters and whole salivary IL-1β and IL-6 levels were comparable among smokers and never-smokers with prediabetes. Among controls, periodontal parameters and whole salivary IL-1β and IL-6 levels were higher among smokers than never-smokers (P <0.05).

CONCLUSIONS

Among controls, periodontal inflammation was worse, and whole salivary IL-1β and IL-6 levels are higher in smokers than never-smokers. Among patients with prediabetes, periodontal inflammation and whole salivary IL-1β and IL-6 levels were comparable between smokers and never-smokers.

Assessment of interleukin-1beta and interleukin-6 in the crevicular fluid around healthy implants, implants with peri-implantitis, and healthy teeth: a cross-sectional study

Objectives

This study aimed to assess and compare the levels of interleukin-1beta (IL-1β) and interleukin-6 (IL-6) in the crevicular fluid around healthy implants, implants with peri-implantitis, and healthy teeth.

Materials and Methods

This study evaluated 16 dental implants in 8 patients (4 males and 4 females). These patients had at least one healthy implant and one implant with peri-implantitis next to healthy teeth. The crevicular fluid was collected using absorbent cones and transferred to the laboratory. Specimens were evaluated by ELISA for interleukin levels. Data were analyzed using repeated measures ANOVA and Bonferroni tests (P<0.05).

Results

Levels of IL-1β in the crevicular fluid around implants with peri-implantitis were significantly higher than around healthy implants (P=0.002); the latter was significantly higher than around healthy teeth (P=0.015). A significant difference was found in the level of IL-6 in the crevicular fluid around implants with peri-implantitis and healthy implants (P=0.049) and also between implants with peri-implantitis and healthy teeth (P<0.001).

Conclusion

Within the limitations of this study, significant differences exist in the levels of IL-1β and IL-6 in the crevicular fluid of implants with peri-implantitis, healthy implants, and healthy teeth. More studies with larger sample sizes in different populations are necessary.

Association among oral health parameters, periodontitis, and its treatment and mortality in patients undergoing hemodialysis

BACKGROUND

Chronic periodontitis (CP) is a continuous, reversible source of inflammation with a potential impact on mortality in patients undergoing hemodialysis (HD). This study investigates the impact of oral health indicators, CP, and its treatment on survival rates in a group of patients undergoing HD.

METHODS

Clinically stable patients undergoing HD were referred for a dental examination. All patients were prospectively followed in the dialysis clinic, and all-cause mortality was recorded. Three groups of patients were analyzed: those who received CP treatment, those who did not, and patients without CP as a control group.

RESULTS

A total of 122 patients (79 males and 43 females, aged 23 to 77 years; mean age: 50 years; range: 23 to 77 years) were enrolled. Forty percent reported having rarely been evaluated by a dentist, and 59% had CP. There were 34 fatal events during a mean follow-up time of 64.1 ± 11.2 months. Oral factors associated with death in the univariate analysis were decreased frequency of dental visits; non-use of dental floss; increased decayed, missing, and filled teeth index; presence of CP; and absence of CP treatment. Patients with CP had a higher risk of death from all causes compared with patients without CP in the univariate analysis for untreated patients (hazard ratio 2.65 [95% confidence interval 1.06 to 6.59]; P = 0.036) and to a lesser extent for treated patients (2.36 [1.01 to 5.59]; P = 0.047). These significant differences were not maintained after adjustments for confounders in the multivariate model.

CONCLUSIONS

These results suggest that poor oral health, including CP, is a common finding in patients undergoing HD. The results of this study call for intervention trials to test the hypothesis that treatment of CP improves survival in maintenance of patients undergoing HD.