Analysis of IL-1β, CXCL8, and TNF-α levels in the crevicular fluid of patients with periodontitis or healthy implants

Biological Processes in Gingival Tissue Integration Around Dental Implants

Peri-implant gingival tissue integration (GTI) is pivotal in determining the long-term success and functionality of dental implants. To enhance GTI, researchers have increasingly focused during the past decade on unraveling the response of gingival tissues to implant surfaces. This increased focus on soft instead of hard tissue integration has led to the development of various models, including in vitro cell culture systems and in vivo animal models, designed to predict and assess GTI around dental implants. However, inconsistent study outcomes between the different models have created confusion, highlighting the need for a comprehensive review. Therefore, the main objective of this review is to present a comprehensive overview of existing in vitro models, ranging from 2D to 3D, specifically designed to investigate cellular behavior relevant to peri-implant GTI. To facilitate a better comprehension of the utility of these models, the review initiates an elucidation of the histological characteristics of gingival tissues surrounding natural dentition, offering insights into the healing dynamics and histological adaptation processes occurring in gingival tissues adjacent to dental implants. In addition, through a critical evaluation of the strengths and limitations inherent in each model, our aim is to contribute to a more profound understanding of their applicability and effectiveness in GTI research.

Evaluating the Efficacy of Gelatin-Chitosan-Tetraethyl Orthosilicate Calcium Hydroxide Composite as a Dental Pulp Medicament on COX-2, PGP 9.5, TNF-α Expression and Neutrophil number

Introduction

Calcium hydroxide (Ca(OH) 2) is the material of choice for pulp therapy. However, Ca(OH) 2 has drawbacks such as toxicity, poor sealing, and tunnel defect formation. Alternative materials have been developed to provide more biocompatible materials with better dentin formation ability. The objective of this study was to evaluate the effect of composites containing gelatin (G), chitosan (CH), tetraethyl orthosilicate (TEOS), and Ca(OH) 2, namely G-CH-TEOS-Ca (OH) 2 (Extended data) on inflammation of the dental pulp (expression of COX-2, PGP 9.5, TNF-α, and neutrophil number).

Materials and methods

A total of 16 Wistar rat models of acute pulp injury were prepared and divided into two groups, treatment and control, 8 with each. In the treatment group, we applied a pulp-capping material using G-CH-TEOS-Ca (OH) 2 and Ca(OH) 2. On the 1 st and 3 rd days, rats were sacrificed. Tissue samples from 4 rats in each group were processed for histological preparation. COX-2, PGP 9.5, and TNF-α were observed using immunohistochemical (IHC) staining, and neutrophil numbers were observed using hematoxylin-eosin staining. Image analysis of COX-2, PGP 9.5, and TNF-α expression was performed using ImageJ software.

Results

The results showed a decrease in COX-2 expression, but not significantly while PGP 9.5 and TNF-α expression were significantly higher than those in the control group. Neutrophil numbers were lower in the treatment group than in the control group, but the difference was not statistically significant.

Conclusion

The G-CH-TEOS-Ca (OH) 2 composite material may have potential as an exposed pulp medicament by reducing inflammation (COX-2 expression and number of neutrophils) and increasing the regeneration factor (TNF-α expression) and nerve (PGP 9.5 expression).

DLK1 regulates periodontal inflammation by inhibiting NF-κB p65 and JNK signaling pathways

The roles and molecular mechanisms of Delta-like 1 (DLK1) in periodontitis remain largely unknown. Here, we investigated the expression of DLK1 and NF-κB p65 in Porphyromonas gingivalis (Pg.)-induced periodontitis in vivo. Periodontal inflammation and alveolar bone resorption were analyzed using western blotting, micro-computed tomography, TRAP staining, immunohistochemistry, and immunofluorescence. Raw246.7 cells were stimulated with 1 μg/ml Porphyromonas gingivalis lipopolysaccharide (Pg.LPS) to assess DLK1 expression in vitro. DLK1 overexpression was achieved, and transfection efficiency was confirmed using western blotting and immunofluorescence. The NF-κB and MAPK pathways were activated by treating cells with 1 μg/ml Pg.LPS to explore related mechanisms. Compared with normal tissues, both DLK1 and NF-κB p65 expression increased in periodontitis gingival tissues. DLK1-positive expression was observed in inflammatory infiltrating cells and osteoclasts in the marginal lacunae of the alveolar bone. DLK1 expression in CD68-positive macrophages was detected by immunofluorescence. However, DLK1 expression in Raw246.7 cells decreased after Pg.LPS stimulation and during osteoclast differentiation. DLK1 levels negatively correlated with TNF-α, IL-1β, and NFATC1. Increased DLK1 in Raw246.7 cells further inhibited COX2 and iNOS expressions. Mechanistically, DLK1 overexpression down-regulated NF-κB p65 and JNK levels. In summary, these findings suggest that DLK1 overexpression inhibits periodontal inflammation through the NF-κB p65 and JNK pathways. Interventions targeting increased DLK1 levels may have therapeutic implications for periodontitis.

Anti-inflammatory effectiveness of Peperomia pellucida (L.) Kunth in rats induced with periodontitis

Background

Periodontitis, marked by deep periodontal pocket depth (PPD), facilitates bacterial colonization and inflammation, necessitating adjunctive therapies. Although 0.2 % chlorhexidine (CHX) mouthwash is effective, its side effects have led to the search for alternative treatments. Peperomia pellucida (L.) Kunth, known as Pepper Elder, is a traditional medicinal plant with potential as an adjunctive herbal therapy for periodontitis.

Objective

This study aimed to investigate the anti-inflammatory efficacy of Peperomia pellucida extract in rats with induced periodontitis.

Methods

A post-test control group design was used in this laboratory experimental study. Four groups of Wistar strain Rattus norvegicus rats were utilized: a Pristine group (without periodontitis), a negative control group (induced periodontitis only), a positive control group (induced periodontitis and administered 0.2 % CHX), and an experimental group (induced periodontitis and administered 2.5 μL of Pepper Elder extract). Each treatment group received daily administration for one week. PPD measurements were taken on days 0, 3, 5, and 7. Blood serum was collected on day 7 for ELISA to measure IL-1β, TNF-α, IL-10, and IL-13 levels. Statistical analysis was performed using the Kruskal-Wallis test with a post hoc LSD and Mann-Whitney test.

Results

The extract-treated rats showed a decrease in PPD, with significant differences between the extract group and the negative control group (p < 0.05). TNF-α levels in the extract group differed significantly from the negative control group (p < 0.05) but not from the Pristine and positive control groups. IL-1β levels differed significantly only from the negative control group. IL-10 levels were significantly different from both the Pristine and negative control groups, while IL-13 levels differed significantly only from the negative control group.

Conclusion

Peperomia pellucida (L.) Kunth extract exhibits anti-inflammatory effects in rats with induced periodontitis.

A Comparative Analysis of the Efficacy of Bacterial Lysate versus Antibiotic Therapy in the Treatment of Experimental Peri-Implantitis in Rats

Peri-implantitis (PI) is a current concern whose understanding and resolution are ongoing. We aimed to evaluate in vivo a new treatment with antibacterial properties, based on bacterial lysates obtained from the strains of Aggregatibacter actinomycetemcomitans, Streptococcus oralis, and Fusobacterium nucleatum. This research was conducted on 30 rats with PI which were divided into three groups and treated with antibiotic and anti-inflammatory (AAi) drugs, bacterial lysates (BLs), and saline (C), respectively. The monitoring period included the clinical and paraclinical examination where hematological, immunological, imaging, and histopathological analysis were performed. No particular clinical signs were observed, but the radiological examination showed the loss of all implants in group C, in contrast to group BL which had the highest survival rate of devices. White cells showed a decrease from the PI period, as did the immunological analysis. Only IL-6 showed an increase in the AAi and BL groups. Histopathologically, the C group presented a high degree of bone destruction, and in the BL group, many attenuated inflammatory phenomena appeared compared to the AAi animals. Bacterial lysates have similar effects to antibiotic-based therapeutic regimens for PI, and their future use may help to improve the current therapeutic management of the disease.

ZIF-8-based Nanoparticles for Inflammation Treatment and Oxidative Stress Reduction in Periodontitis

Periodontitis, an inflammatory bone resorption disease associated with dental plaque, poses significant challenges for effective treatment. In this study, we developed Mino@ZIF-8 nanoparticles inspired by the periodontal microenvironment and the unique properties of zeolitic imidazolate framework 8, aiming to address the complex pathogenesis of periodontitis. Transcriptome analysis revealed the active engagement of Mino@ZIF-8 nanoparticles in innate and adaptive inflammatory host defense and cellular metabolic remodeling. Through sustained release of the anti-inflammatory and antibacterial agent minocycline hydrochloride (Mino) and the generation of Zn2+ with pro-antioxidant effects during degradation, Mino@ZIF-8 nanoparticles synergistically alleviate inflammation and oxidative damage. Notably, our study focuses on the pivotal role of zinc ions in mitochondrial oxidation protection. Under lipopolysaccharide (LPS) stimulation, periodontal ligament cells undergo a metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis, leading to reduced ATP production and increased reactive oxygen species levels. However, Zn2+ effectively rebalances the glycolysis-OXPHOS imbalance, restoring cellular bioenergetics, mitigating oxidative damage, rescuing impaired mitochondria, and suppressing inflammatory cytokine production through modulation of the AKT/GSK3β/NRF2 pathway. This research not only presents a promising approach for periodontitis treatment but also offers novel therapeutic opportunities for zinc-containing materials, providing valuable insights into the design of biomaterials targeting cellular energy metabolism regulation.

Effect of scaling on levels of interleukin 1-beta and clinical periodontal parameters among e-cigarette users and non-smokers: A prospective study

INTRODUCTION

This cohort study aimed to compare the effect of ultrasonic scaling on the expression of IL-1β in the gingival crevicular fluid (GCF) among ENDS users and non-smokers (NS) with gingivitis.

METHODS

Self-reported current electronic nicotine delivery system (ENDS) users and NS with generalized gingivitis were included in this study. All the patients underwent scaling at the baseline visit (T0). Clinical measures, periodontal parameters [probing depth (PD), plaque index (PI), and bleeding on probing (BOP)], and GCF IL-1β were measured at T0, after 1 week (T1) and after 3 weeks (T2). Wilcoxon signed rank test was used to assess the changes in the periodontal measurements and IL-1β levels at different time points and Mann-Whitney U Test was used to compare the two groups.

RESULTS

A total of 38 individuals (18 NS and 20 ENDS users) participated in the study. The PD was significantly higher in ENDS users than in NS at baseline. However, the PI and BOP were similar in all groups at baseline. At T1, the PI was significantly lower for NS than for ENDS users (p=0.045). At T2, there were no significant differences in any of the parameters assessed between the two groups. For ENDS users, BOP was significantly lower at T1 than at baseline. For NS, the BOP at T1 and T2 and the PI at T1 were significantly lower than at baseline. There was no difference in the GCF IL-1β levels in NS and ENDS users at baseline, T1, and T2. At T2, there was a significant reduction in IL-1β (p<0.05) than at baseline in both groups.

CONCLUSIONS

Both ENDS users and NS with gingivitis responded similarly to scaling. GCF IL-1β levels were significantly higher at baseline (p<0.05) compared with their levels at T1 and T2 for both the groups.

CLINICAL TRIAL REGISTRATION

The study was registered on the official website of ClinicalTrials.gov.

IDENTIFIER

ID NCT05745324.

Preventing Sports Injuries in Korean National Badminton Team Candidates: A Field Investigation of Exercise-Related Injuries, Focused on National Team Candidate Training Camps

PURPOSE This study aimed to investigate the occurrence of sports injuries among badminton national team candidates during training camps and to identify appropriate measures for players to effectively manage and respond to such injuries in the future.METHODS The participants consisted of 123 individuals who took part in national team candidate training camps for badminton in 2022 and 2023. Record sheets were utilized to document the athletes' thoughts and opinions related to exercise injuries during the training period.RESULTS Badminton national team candidates experienced exercise-related injuries in various areas, including the ankles, thighs, knees, hips, shoulders, and back. Female players had a higher incidence of lower body injuries compared to their male counterparts. Through interviews with players about these injuries, individualized approaches involving appropriate rest and training adjustments were found to be necessary; additionally, educating the players about rehabilitation strategies for exercise injuries is essential.CONCLUSIONS When conducting recreational training activities, it is important to avoid fostering excessive competitive attitudes. Additionally, if potential risks are present within the exercise environment, it is crucial to assess and address these with the utmost caution.

Construction of a diagnostic model based on random forest and artificial neural network for peri-implantitis

OBJECTIVES

This study aimed to reveal critical genes regulating peri-implantitis during its development and construct a diagnostic model by using random forest (RF) and artificial neural network (ANN).

METHODS

GSE-33774, GSE106090, and GSE57631 datasets were obtained from the GEO database. The GSE33774 and GSE106090 datasets were analyzed for differential expression and functional enrichment. The protein-protein interaction networks (PPI) and RF screened vital genes. A diagnostic model for peri-implantitis was established using ANN and validated on the GSE33774 and GSE57631 datasets. A transcription factor-gene interaction network and a transcription factor-micro-RNA (miRNA) regulatory network were also established.

RESULTS

A total of 124 differentially expressed genes (DEGs) involved in the regulation of peri-implantitis were screened. Enrichment analysis showed that DEGs were mainly associated with immune receptor activity and cytokine receptor activity and were mainly involved in processes such as leukocyte and neutrophil migration. The PPI and RF screened six essential genes, namely, CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8. The receiver operating characteristic curve (ROC) indicated that the ANN model had an excellent diagnostic performance. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 may be a key miRNA.

CONCLUSIONS

The diagnostic model of peri-implantitis constructed by RF and ANN has high confidence, and CD38, CYBB, FCGR2A, SELL, TLR4, and CXCL8 are potential diagnostic markers. FOXC1, GATA2, and NF-κB1 may be essential transcription factors in peri-implantitis, and hsa-miR-204 plays a vital role as a critical miRNA.

Long non-coding RNA X-Inactive Specific Transcript (XIST) interacting with USF2 promotes osteogenic differentiation of periodontal ligament stem cells through regulation of WDR72 transcription

BACKGROUND

Periodontal ligament stem cells (PDLSCs) are the most potential cells in periodontal tissue regeneration and bone tissue regeneration. Our prior work had revealed that WD repeat-containing protein 72 (WDR72) was crucial for osteogenic differentiation of PDLSCs. Here, we further elucidated its underlying mechanism in PDLSC osteogenic differentiation.

METHODS

Human PDLSCs, isolated and identified by flow cytometry, were prepared for osteogenic differentiation induction. Levels of WDR72, long non-coding RNA X-Inactive Specific Transcript (XIST), upstream stimulatory factor 2 (USF2), and osteogenic marker genes (Runx2, Osteocalcin, and Collagen I) in human PDLSCs and clinical specimens were detected by RT-qPCR. Protein expressions of WDR72, Runx2, Osteocalcin, and Colla1 were tested by Western blot. The interactions among the molecules were verified by RIP, RNA pull-down, ChIP, and luciferase reporter assays. Osteogenic differentiation was evaluated by alkaline phosphatase (ALP) and alizarin red staining (ARS).

RESULTS

WDR72 was decreased in periodontal tissues of periodontitis patients, and overexpression reversed TNF-α-mediated suppressive effects on PDLSC osteogenic differentiation. Mechanically, XIST recruited the enrichment of USF2 to the WDR72 promoter region, thereby positively regulating WDR72. WDR72 silencing overturned XIST-mediated biological effects in PDLSCs.

CONCLUSION

WDR72, regulated by the XIST/USF2 axis, enhances osteogenic differentiation of PDLSCs, implying a novel strategy for alleviating periodontitis.

Salivary interleukin-1β as a biomarker to differentiate between periodontal health, gingivitis, and periodontitis

BACKGROUND

Periodontal diagnosis is based on recording clinical parameters including bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment loss (CAL). These techniques may be prone to errors due to different factors. Available biomarkers in the oral biofluid such as interleukin (IL)-1β could provide solutions for these issues. The study aimed to determine the potential of salivary IL-1β to differentiate periodontal health from disease and between gingivitis and periodontitis.

METHODS

Patients with gingivitis (N.=25), periodontitis (N.=50), and healthy periodontium (N.=25) were recruited for this study. For each patient, whole unstimulated saliva was collected followed by recording periodontal parameters namely; Plaque Index (PI), BOP, PPD, CAL. Level of salivary IL-1β was assayed by using enzyme-linked immunosorbent assays. Sensitivity and specificity of IL-1β, to differentiate any given condition, was determined by Receiver operating characteristic curve and area under the curve (AUC).

RESULTS

Both BOP and PI were significantly higher in association with gingivitis and periodontitis groups as compared to controls. Concentration of salivary IL-1β in periodontal health was significantly lower than gingivitis and periodontitis groups. The biochemical analyses showed that salivary IL-1β differentiated periodontal health from gingivitis (AUC 0.949) and periodontitis (AUC 0.852) but could not discriminate gingivitis from periodontitis (AUC 0.532). The proposed cut-off points to differentiate periodontal health from gingivitis was 103.8 pg/mL, while the value of the biomarker to differentiate periodontal health from periodontitis was 102.0 pg/mL.

CONCLUSIONS

Salivary IL-1β could be a reliable biomarker with a good level of accuracy to differentiate periodontal health from disease but not to discriminate gingivitis from periodontitis.

Current Molecular, Cellular and Genetic Aspects of Peri-Implantitis Disease: A Narrative Review

(1) Background: Peri-implantitis is a multi-factorial disease with an inflammatory background that occurs in both soft and hard tissues surrounding implants. In recent years, the understanding of the cellular, molecular and genetic background of peri-implantitis has broadened. This study aims to summarize the currently available articles on the subject and highlight the most recent advances over the last 20 years. (2) Methods: For this study, the Embase and PubMed libraries were searched using the keywords: ("peri-implantitis" AND "cytokine" OR "genetics" OR "cellular") and ("peri-implantitis" AND "cytokine" OR "genetics" OR "cellular" AND "risk factors"). The search revealed a total of 3013 articles (992 from PubMed, 2021 from Embase). Following screening of the titles and abstracts and full-text reads, 55 articles were included. (3) Results: In peri-implantitis IL-6, IL-1β, TNF-α, MMP-8 and their genetic variations appear to be the most important cytokines in relation to not only pathogenesis, but also their potential diagnostic capabilities. Epithelial and inflammatory cells, along with those of the bone lineage, are prime cellular elements found in peri-implantitis. (4) Conclusions: A wide array of cells stand behind peri-implantitis, as well as cytokines and their genetic variations that take part in the process. However, the growing interest in this topic has led to the introduction of specific new diagnostic tools to enable a better understanding of patients' responses to treatment and, in turn, to even enable prediction of the risk of developing peri-implant disease.

Periodontal, Microbiological, and Proinflammatory Cytokines Levels in Fixed Orthodontics Patients Treated with Photodynamic Therapy Adjunct to Full Mouth Scaling

Objective: To assess the efficiency of photodynamic therapy (PDT) adjunct to full mouth scaling (FMS) in improving periodontal, microbiological, and proinflammatory cytokines levels in patients undergoing fixed orthodontics treatment (FOT). Materials and methods: The study recruited 60 teenage patients who were undergoing FOT. All the patients were arbitrarily divided into two groups: Group 1, FMS +PDT and Group 2, FMS alone. Plaque scores (PS), bleeding on probing (BOP), and probing depth (PD) were assessed. Levels of biomarkers interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-α) using enzyme-linked immunosorbent assay were evaluated. Samples were collected from gingival plaque for estimation of Prevotella intermedia and Porphyromonas gingivalis load. All measurements were completed at three intervals baseline, 4th week, and 8th week. Post Hoc corrections and intergroup comparisons were examined using Student's t-test and Bonferroni correction. To find differences between repeated follow-ups, analysis of variance (ANOVA) multiple rank tests were used. Results: At baseline, all the gingival parameters displayed comparable outcomes between patients of Group 1 and Group 2 (p > 0.05). However, at 4 and 8 weeks of follow-up, PS and BOP among tested groups exhibited significantly lower values than baseline (p < 0.001). At 8 weeks, there was a significant difference in PS between the two groups tested. Moreover, at 4 and 8 weeks, BOP revealed a significant difference between the groups. PD remains comparable with baseline at follow-up visits (p > 0.05). A significant decrease in IL-6 and TNF-α levels was observed in both investigated groups at 4 and 8 weeks of baseline. Moreover, it was identified that P. intermedia and P. gingivalis were reduced significantly at 4 weeks. Moreover, a significant difference existed between both Group 1 and Group 2 at 4 and 8 weeks of recall visit (p < 0.05). Conclusions: The use of photodynamic treatment adjuvant to FMS aids in improving periodontal parameters and cytokines levels.

Suppression of the NLRP3 Inflammasome through Activation of the Transient Receptor Potential Channel Melastatin 2 Promotes Osteogenesis in Tooth Extraction Sockets of Periodontitis

This study explored the role of transient receptor potential channel melastatin 2 (TRPM2)-mediated activation of NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome in osteogenesis during healing of tooth extraction sockets. Tooth extraction socket tissue samples were collected from patients with or without periodontitis. In a TRPM2 knockout mouse model of socket healing, mice with or without periodontitis and their wild-type littermates were used for comparing the socket healing phenotypes. Micro-computed tomography imaging, three-dimensional reconstruction of the sockets, and hematoxylin and eosin staining for histopathologic analysis were performed. Immunofluorescence, immunohistochemistry, and Western blot analysis were used for evaluation of protein expression; the mRNA levels were evaluated by quantitative RT-PCR. Osteogenic, chondrogenic, and adipogenic differentiation potential of human bone marrow mesenchymal stem cells (BMMSCs) was evaluated. Calcium deposition was evaluated using Alizarin Red S staining. NLRP3 and CASP1 were up-regulated in tooth sockets of periodontitis patients. NLRP3 knockdown promoted the osteogenic differentiation of maxillary BMMSCs under inflammatory conditions. TRPM2 was up-regulated in the tooth extraction socket tissue of periodontitis. Inhibiting TRPM2 expression mitigated the NLRP3 inflammasome and its deleterious effect on osteogenesis. Activation of the TRPM2 ion channel regulated osteogenesis of BMMSCs under inflammatory conditions via Ca²⁺ influx, the mitochondrial dynamics, and pyroptosis. Targeting the TRPM2/Ca²⁺/NLRP3 axis could be beneficial in the healing process of the tooth extraction sockets of patients with periodontitis.

Antimicrobial and anti-inflammatory activity of Cystatin C on human gingival fibroblast incubated with Porphyromonas gingivalis

Background

Periodontal disease is considered one of the most prevalent chronic infectious diseases, often leading to the disruption of tooth-supporting tissues, including alveolar bone, causing tooth mobility and loss. Porphyromonas gingivalis is considered the major etiological agent of this disease, having a plethora of virulence factors, including, lipopolysaccharides (LPS), hemolysins, and proteinases. Antimicrobial peptides are one of the main components of the innate immune response that inhibit the growth of P. gingivalis. The aim of this study was to analyze the antimicrobial activity of cystatin C and to assess the effect on the inflammatory and anti-inflammatory cytokines, the production of reactive oxygen species, and in the release of nitric oxide by human gingival fibroblasts incubated with P. gingivalis in the presence and absence of cystatin C.

Methods

P. gingivalis ATCC 33277 was exposed to cystatin C for 24h and co-cultured with human gingival fibroblasts (HGFs) ATCC CRL-2014. The effect of cystatin on growth of P. gingivalis and HGFs was evaluated. Pro-inflammatory (TNFα, IL-1β) and anti-inflammatory (IL-10) cytokines were determined by ELISA in the supernatants of HGFs incubated with P. gingivalis exposed to cystatin C. Additionally, nitrites and reactive oxygen species (ROS) production were evaluated.

Results

Cystatin Cinhibited the growth of P. gingivalis without affecting HGFs. Incubation of HGFs with P. gingivalis led to a significant increase of TNF-α and IL-1β. In contrast, HGFs incubated with P. gingivalis exposed to cystatin C showed a decreased production of both cytokines, whereas IL-10 was enhanced. Incubation of HGFs with P. gingivalis led to an increase of nitric oxide (NO) and ROS production, which was reduced in the presence of the peptide.

Conclusions

Cystatin C inhibits the growth of P. gingivalis and decreases the inflammatory cytokines, ROS, and NO production during infection of HGFs with P. gingivalis. Knowledge on the antimicrobial and immunomodulatory properties of cystatin C could aid in the design of new therapeutic approaches to facilitate the elimination of this bacterium to improve the treatment of periodontal disease.

Porphyromonas gingivalis and dental stem cells crosstalk amplify inflammation and bone loss in the periodontitis niche

Periodontitis is the sixth most prevalent disease, and almost 3.5 billion people are affected globally by dental caries and periodontal diseases. The microbial shift from a symbiotic microbiota to a dysbiotic microbiota in the oral cavity generally initiates periodontal disease. Pathogens in the periodontal microenvironment interact with stem cells to modulate their regenerative potential. Therefore, this review focuses on the interaction between microbes and stem cells in periodontitis conditions. Microbes direct dental stem cells to secrete a variety of pro-inflammatory cytokines and chemokines, which increase the inflammatory burden in the damaged periodontal tissue, which further aggravates periodontitis. Microbial interaction also decreases the osteogenic differentiation potential of dental stem cells by downregulating alkaline phosphatase, runt-related transcription factor 2, type 1 collagen, osteocalcin, osteopontin, and so on. Microbe and stem cell interaction amplifies pro-inflammatory cytokine signaling in the periodontitis niche, decreasing the osteogenic commitment of dental stem cells. A clear understanding of microbial stem cell interactions is crucial in designing regenerative therapies using stem cells in the management of periodontitis.

The expression and clinical significance of miR-30b-3p and miR-125b-1-3p in patients with periodontitis

OBJECTIVE

Periodontitis is a chronic inflammatory infectious disease caused by the deposition of dental plaque on the tooth surface, leading to adverse systemic consequences. Accumulating evidence shows that dysregulated microRNAs (miRNAs) are associated with the disease severity of periodontitis. Herein, we report two novel miRNAs, miR-30b-3p and miR-125b-1-3p, in the context of periodontitis and their relationships with disease severity of periodontitis.

METHODS

The miRNA profiles of gingival crevicular fluid (GCF) samples were used to screen differentially expressed miRNAs (DEmiRNAs) between periodontitis patients and periodontally healthy individuals. Clinical human GCF samples were collected from 80 patients diagnosed with periodontitis (PD +) for the first time and 100 periodontally healthy individuals (PD-). The severity of periodontitis was categorized into mild/moderate (MPD) and severe (SPD) groups. The expressions of miR-30b-3p and miR-125b-1-3p were determined by quantitative real-time PCR. The levels of IL-1β, IL-6, and TNF-α were determined by ELISA methods.

RESULTS

We applied GEO2R bioinformatics tool to analyze the raw data of the GSE89081 dataset and identified miR-30b-3p (|logFC|= 1.987) and miR-125b-1-3p (|logFC|= 1.878) between periodontitis patients and periodontally healthy individuals. It was found that PPD, CAL, BOP, and the relative expression levels of miR-30b-3p and miR-125b-1-3p were all higher in the PD + group than the PD- group, in the SPD group than the MPD group (P < 0.05). The periodontitis patients with high-miR-30b-3p expression exhibited increased PPD, CAL, and BOP compared to those low-miR-30b-3p expression, while high-miR-125b-1-3p expression group showed significant differences on PPD and BOP from low-miR-125b-1-3p expression group (P < 0.05). Pearson correlation analysis demonstrated a significantly positive correlation between the levels of inflammatory cytokines, miR-30b-3p expression, and miR-125b-1-3p expression (P < 0.001). Results of ROC curves showed AUC of 0.878 and 0.927, sensitivity of 0.843 and 0.855, and specificity of 0.791 and 0.801, respectively, when miR-30b-3p and miR-125b-1-3p expression levels were used to diagnose periodontitis.

CONCLUSION

These data unveiled that miR-30b-3p and miR-125b-1-3p expressions may be associated with the pathogenesis of periodontitis.

Role of ferroptosis-related genes in periodontitis based on integrated bioinformatics analysis

Background

Cell survival or death is one of the key scientific issues of inflammatory response. To regulate cell death during the occurrence and development of periodontitis, various forms of programmed cell death, such as pyroptosis, ferroptosis, necroptosis, and apoptosis, have been proposed. It has been found that ferroptosis characterized by iron-dependent lipid peroxidation is involved in cancer, degenerative brain diseases and inflammatory diseases. Furthermore, NCOA4 is considered one of ferroptosis-related genes (FRGs) contributing to butyrate-induced cell death in the periodontitis. This research aims to analyze the expression of FRGs in periodontitis tissues and to explore the relationship between ferroptosis and periodontitis.

Method

Genes associated with periodontitis were retrieved from two Gene Expression Omnibus datasets. Then, we normalized microarray data and removed the batch effect using the R software. We used R to convert the mRNA expression data and collected the expression of FRGs. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), transcription factor (TF) and protein-protein interaction (PPI) network analyses were used. In addition, we constructed a receiver operating characteristic curve and obtained relative mRNA expression verified by quantitative reverse-transcription polymerase chain reaction (PCR).

Results

Eight and 10 FRGs related to periodontitis were upregulated and downregulated, respectively. GO analysis showed that FRGs were enriched in the regulation of glutathione biosynthetic, glutamate homeostasis, and endoplasmic reticulum-nucleus signaling pathway. The top TFs included CEBPB, JUND, ATF2. Based on the PPI network analysis, FRGs were mainly linked to the negative regulation of IRE1-mediated unfolded protein response, regulation of type IIa hypersensitivity, and regulation of apoptotic cell clearance. The expression levels of NCOA4, SLC1A5 and HSPB1 using PCR were significantly different between normal gingival samples and periodontitis samples. Furthermore, the diagnostic value of FRGs for periodontitis were “Good”.

Conclusions

We found significant associations between FRGs and periodontitis. The present study not only provides a new possible pathomechanism for the occurrence of periodontitis but also offers a new direction for the diagnosis and treatment of periodontitis.

IL-18 Gene Promoter Polymorphisms are Involved in Periodontal Disease: A Meta-Analysis

Microbial plaque that builds up in the gingival crevice area causes inflammation and leads to periodontal disease. Previous research has shown an association between interleukins with periodontitis. The association between interleukin-18 (IL-18) gene polymorphism and periodontitis risk was studied extensively, but the results are contradictory. The aim of this study is to find the association of two IL-18 promoter variants namely -607 C > A (rs1946518) and -137 G > C (rs187238), and the risk of chronic and aggressive periodontal disease by meta-analysis. The databases of PubMed, Medline, Web of Science, and Google Scholar were all explored to find the appropriate studies. The MetaGenyo software was used to calculate each analysis. Outcomes of the pooled analyses revealed significantly elevated risk for periodontitis for both polymorphisms. There is no significant heterogeneity between studies. No significant publication bias was observed. This meta-analysis provided the evidence of a link between IL-18 gene polymorphism in periodontitis.

Identification of Potential Genetic Biomarkers and Target Genes of Peri-Implantitis Using Bioinformatics Tools

Objectives

To investigate potential genetic biomarkers of peri-implantitis and target genes for the therapy of peri-implantitis by bioinformatics analysis of publicly available data.

Methods

The GSE33774 microarray dataset was downloaded from the Gene Expression Omnibus (GEO). The differentially expressed genes (DEGs) between peri-implantitis and healthy gingival tissues were identified using the GEO2R tool. GO enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed using the DAVID database and the Metascape tool, and the results were expressed as a bubble diagram. The protein-protein interaction network of DEGs was constructed using the Search Tool for the Retrieval of Interacting Genes (STRING) and visualized using Cytoscape. The hub genes were screened by the cytoHubba plugin of Cytoscape. The potential target genes associated with peri-implantitis were obtained from the DisGeNET database and the Open Targets Platform. The intersecting genes were identified using the Venn diagram web tool.

Results

Between the peri-implantitis group and the healthy group, 205 DEGs were investigated including 140 upregulated genes and 65 downregulated genes. These DEGs were mainly enriched in functions such as the immune response, inflammatory response, cell adhesion, receptor activity, and protease binding. The results of KEGG pathway enrichment analysis revealed that DEGs were mainly involved in the cytokine-cytokine receptor interaction, pathways in cancer, and the PI3K-Akt signaling pathway. The intersecting genes, including IL6, TLR4, FN1, IL1β, CXCL8, MMP9, and SPP1, were revealed as potential genetic biomarkers and target genes of peri-implantitis.

Conclusions

This study provides supportive evidence that IL6, TLR4, FN1, IL1β, CXCL8, MMP9, and SPP1 might be used as potential target biomarkers for peri-implantitis which may provide further therapeutic potentials for peri-implantitis.