Therapeutic Effect of a Novel M1 Macrophage-Targeted Nanodrug in Chronic Periodontitis Mice.

Chronic periodontitis is a chronic, progressive, and destructive disease. Especially, the large accumulation of advanced glycation end products (AGEs) in a diseased body will aggravate the periodontal tissue damage, and AGEs induce M1 macrophages. In this project, the novel nanodrugs, glucose-PEG-PLGA@MCC950 (GLU@MCC), are designed to achieve active targeting with the help of glucose transporter 1 (GLUT1) which is highly expressed in M1 macrophages induced by AGEs. Then, the nanodrugs release MCC950, which is a kind of NLRP3 inhibitor. These nanodrugs not only can improve the water solubility of MCC950 but also exhibit superior characteristics, such as small size, stability, innocuity, etc. In vivo experiments showed that GLU@MCC could reduce periodontal tissue damage and inhibit cell apoptosis in periodontitis model mice. In vitro experiments verified that its mechanism of action might be closely related to the inhibition of the NLRP3 inflammatory factor in M1 macrophages. GLU@MCC could effectively reduce the damage to H400 cells caused by AGEs, decrease the expression of NLRP3, and also obviously reduce the M1-type macrophage pro-inflammatory factors such as IL-18, IL-1ß, caspase-1, and TNF-α. Meanwhile, the expression of anti-inflammatory factor Arg-1 in the M2 macrophage was increased. In brief, GLU@MCC would inhibit the expression of inflammatory factor NLRP3 and exert antiperiodontal tissue damage in chronic periodontitis via GLUT1 in the M1 macrophage as the gating target. This study provides a novel nanodrug for chronic periodontitis treatment.

Effect of non-surgical periodontal therapy on CD14 + CD16+ monocyte counts in peripheral blood samples: a clinical interventional study.

Monocytes and their macrophage progeny are thought to be involved in tissue and alveolar bone destruction in periodontal disease. It has been documented that the proportion of (CD14 + CD16+) non-classical monocytes in the blood are elevated in chronic periodontitis;A total of 20 chronic generalized periodontitis patients who were otherwise healthy, were recruited for this study. At baseline and 3 weeks after non-surgical periodontal treatment, peripheral blood was obtained to assess the levels of C-reactive protein (CRP) and the proportion of monocyte subsets. Monocyte subsets were assessed using flow cytometry;The mean percentage of CD14 + CD16+ non-classical monocytes in the peripheral blood sample at baseline was 13.95 + 2.09, that reduced to 8.94 + 1.23 3 weeks after non-surgical treatment. A distinct significant reduction in the percentage of non-classical monocytes and a concomitant increase in classical monocytes were observed following periodontal treatment compared to baseline. There was a significant reduction in the all the periodontal parameters and CRP levels 3 weeks post non-surgical periodontal treatment. A positive correlation between CRP and percentage of non-classical monocytes was also observed; Periodontal treatment potentially modulates the host response effectively.

Evaluation of salivary IL-8 and calcium levels in postmenopausal females with and without periodontitis-A comparative study.

Background and Objective: Menopause is a normal developmental stage in a woman's life marking the permanent cessation of menstruation. Calcium is predominant in intracellular signalling and its intracellular increase can affect the cell's proliferation, phagocytosis and cytokine secretion. IL-8 expression in various cells such as neutrophils and osteoblasts was reported to involve a calcium signalling pathway. Well-known functions of IL-8 includes help in angiogenesis, role in tumour progression, tissue remodelling, etc., Hence, the aim of this study was to establish the relationship between calcium-dependent IL-8 and periodontal disease in postmenopausal females. Method: The study population included 52 postmenopausal women aged 45-57 years. The patients were divided into two groups in which group I included postmenopausal women without periodontitis and group II with periodontitis. Unstimulated salivary samples were collected from all the participants to evaluate IL-8 and calcium levels. Results: There was a statistically significant difference in salivary IL-8 levels between the two groups (P < 0.001), but there was no statistical difference in salivary calcium levels between the two groups (P = 0.730). A weak negative correlation between salivary IL-8 and calcium was found in group I, while a weak positive correlation was found between the same in group II. Conclusion: Analysis of salivary IL-8 from the present study was in accordance with several previous studies. It can be concluded that saliva can also be used as a reliable oral diagnostic fluid for IL-8 and calcium detection in periodontitis.

Association between lipid metabolism and periodontitis in obese patients: a cross-sectional study.

BACKGROUND: To investigate the association between clinical periodontal parameters of periodontitis, serum lipid metabolism markers and adipokines' levels in patients with obesity and periodontitis. METHODS: A total of 112 patients admitted to Hospital of Xi'an Jiaotong University were included in this study. They were divided into normal body weight group (18.5 < body mass index, BMI < 25, n = 36), overweight group (25 ≤ BMI < 30, n = 38), and obesity group (BMI ≥ 30, n = 38) accordingly. The diagnosis of periodontitis was based on the newest international classification of periodontitis. Full-mouth clinical periodontal measurements included: plaque index, periodontal pocket depth, clinical attachment level, and bleeding on probing. Gingival crevicular fluid samples were analyzed for: Interleukin-1ß, tumor necrosis factor-α, Interleukin-6 and C-reactive protein. Serum triglycerides, total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and glycosylated hemoglobin levels were measured. Visfatin, leptin, resistin, and adiponectin levels in serum were also measured. RESULTS: The ratio of participants without periodontitis was significantly highest in normal weight group, and the proportion of severe periodontitis (stage III and IV) was highest in obesity group. The periodontal pocket depth, clinical attachment level, and the inflammatory cytokines in gingival crevicular fluid in obesity group and overweight group were higher than those in normal body weight group. The BMI and waist-to-hip ratio (WHR) were significantly positive correlated with periodontal pocket depth and clinical attachment level. Using a Multivariate logistic regression model, periodontitis correlates to BMI, WHR, serum levels of triglyceride, total cholesterol, low density lipoprotein, and adipokines such as visfatin, leptin, and resistin. CONCLUSIONS: Obesity is positively correlated with the aggravation of periodontitis. Obesity may aggravate the damage to periodontal tissue by regulating the secretion level of adipokines.

Gingival crevicular fluid periodontal ligament-associated protein-1, sclerostin, and tumor necrosis factor-alpha levels in periodontitis.

BACKGROUND: In periodontitis, the equilibrium between bone formation and resorption skews in favor of bone loss. Periodontal ligament-associated protein-1 (PLAP-1) and sclerostin play a significant role in the suppression of bone formation. Tumor necrosis factor-alpha (TNF-α) is a central proinflammatory cytokine related to periodontal bone loss. This study aims to assess gingival crevicular fluid (GCF) PLAP-1, sclerostin, and TNF-α levels in individuals with periodontal disease. METHODS: Seventy-one individuals diagnosed with generalized stage III grade C periodontitis (n = 23), gingivitis (n = 24), and periodontal health (n = 24) were included in the study. Full-mouth clinical periodontal measurements were performed. PLAP-1, sclerostin, and TNF-α total amounts in GCF were quantified by ELISA. Nonparametric methods were used for the data analyses. RESULTS: Periodontitis group exhibited significantly higher GCF PLAP-1, sclerostin and TNF-α levels compared with gingivitis and periodontally healthy groups (p < 0.05). GCF PLAP-1 and TNF-α levels of gingivitis group were higher than healthy controls (p < 0.05) whereas GCF sclerostin levels were similar in two groups (p > 0.05). Significant positive correlations were found between GCF PLAP-1, sclerostin and TNF-α levels and all clinical parameters (p < 0.01). CONCLUSIONS: To our knowledge, this is the first study showing GCF PLAP-1 levels in periodontal health and disease. Increased GCF PLAP-1 and sclerostin levels and their correlations with TNF-α in periodontitis imply that those molecules might be involved in the pathogenesis of periodontal disease. Further studies in larger mixed cohorts are needed to enlighten the possible role of PLAP-1 and sclerostin in periodontal bone loss.

Salivary irisin level is higher and related with interleukin-6 in generalized periodontitis.

OBJECTIVES: Irisin plays an important role in energy homeostasis, inflammation, glucose, and lipid metabolism, and it is shown to have relations with many inflammatory diseases. The aim of the study was to determine saliva and serum irisin and IL-6 levels in patients with stage III/grade B periodontitis compared with individuals with healthy periodontium. MATERIALS AND METHODS: Twenty patients with stage III grade B periodontitis (P) and 20 periodontally healthy subjects (control; C) were included in this study. Clinical periodontal measurements were recorded. Saliva and serum levels of irisin and interleukin-6 (IL-6) were analyzed by enzyme-linked immunosorbent assay. RESULTS: Salivary irisin and IL-6 levels were significantly higher in the periodontitis group (p < 0.001, p = 0.002, respectively). Furthermore, serum IL-6 levels were found significantly higher in the periodontitis group compared with controls (p = 0.011). There was no significant difference between the periodontitis and control for serum irisin levels (p > 0.05). Significant positive correlations were found between all periodontal parameters and salivary irisin and IL-6 (p < 0.05) and also between BMI and saliva and serum IL-6 (respectively; r = 0.530, r = 0.329, p < 0.05). There was a positive correlation between salivary irisin and IL-6 (r = 0.369, p < 0.05). CONCLUSIONS: Monitoring of salivary irisin and IL-6 might be potential biomarker for predicting the susceptibility to periodontitis. CLINICAL RELEVANCE: Scientific rationale for the study: Irisin is a novel adipomyokine that has played an important role in energy homeostasis, glucose and lipid metabolism, angiogenesis, immunity, and inflammation. Irisin is involved in the pathogenesis of diseases affecting many body systems. IL-6, another adipomyokine, is a major inflammatory mediator and homeostatic regulator of glucose and lipid metabolism and is associated with periodontitis. No studies investigated the relationship between advanced periodontal disease, irisin, and IL-6 together. PRINCIPAL FINDINGS: The salivary irisin and IL-6 levels were significantly higher and positively correlated in patients with periodontitis relative to healthy controls. Furthermore, serum IL-6 levels were significantly increased in patients with periodontitis. PRACTICAL IMPLICATIONS: The study shows that irisin and IL-6 can be candidate salivary biomarkers for periodontitis and predict to periodontal status.

Cyclic di-adenosine monophosphate regulates the osteogenic and adipogenic differentiation of hPDLSCs via MAPK and NF-κB signaling.

Cyclic di-adenosine monophosphate (c-di-AMP) is a bacterial second messenger that can be recognized by infected host cells and activate the immunoinflammatory response. The purpose of this study is to demonstrate the effect of c-di-AMP on the differentiation of human periodontal ligament stem cells (hPDLSCs) and its underlying mechanisms. In the present study, we find that the gingival crevicular fluid (GCF) of patients with chronic periodontitis has a higher expression level of c-di-AMP than that of healthy people. In vitro, c-di-AMP influences the differentiation of hPDLSCs by upregulating Toll-like receptors (TLRs); specifically, it inhibits osteogenic differentiation by activating NF-κB and ERK/MAPK and promotes adipogenic differentiation through the NF-κB and p38/MAPK signaling pathways. Inhibitors of TLRs or activated pathways reduce the changes induced by c-di-AMP. Our results establish the potential correlation among bacterial c-di-AMP, periodontal tissue homeostasis and chronic periodontitis pathogenesis.

Oxidative stress in human gingival fibroblasts from periodontitis versus healthy counterparts.

OBJECTIVE: Elevated p53 promotes oxidative stress and production of pro-inflammatory cytokines in liposaccharide (LPS)-treated healthy human gingival fibroblasts (HGFs). This study compared oxidative stress, production of inflammatory cytokines, and p53 expression in HGFs from patients with chronic periodontitis (CP) and healthy subjects in vitro upon LPS from Porphyromonas gingivalis challenge. METHODS: Human gingival fibroblasts were isolated from 6 biopsies-3 from healthy donors and 3 from diseased area in CP (Grade B, Stage III). HGFs were cultured with or without 1 µg/ml 24 h LPS. Oxidative stress was assessed by analyzing the level of reactive oxygen species (ROS). Mitochondrial membrane potential and respiration were determined by immunofluorescence and respirometry, respectively. Tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1ß were determined by enzyme-linked immunosorbent assay. P53 expression was monitored by Western blot and immunofluorescence. RESULTS: Human gingival fibroblasts from CP exhibited increased levels of mitochondrial p53, enhanced ROS production, decreased mitochondrial membrane potential, increased mitochondrial oxygen consumption, and increased secretion of TNF-α, IL-6, and IL-1ß, as compared to HGFs from healthy donors. Moreover, LPS exacerbated these changes. CONCLUSION: Human gingival fibroblasts from CP exhibited stronger basal and LPS-inducible oxidative stress and inflammatory response as compared to HGFs from healthy subjects by increased p53 in mitochondria.

Chemerin contributes to inflammatory responses and suppresses osteogenic differentiation in chronic periodontitis.

BACKGROUND: Chronic periodontitis (CP) is a common disease of oral cavity, and approximately 35% of adults suffered from CP. Therefore, its underlying mechanism needs to be explored for new therapeutic approaches. Chemerin, as a multifunctional adipokine, is found to be highly expressed in the gingival crevicular fluid (GCF), gingival tissues and the plasma of periodontitis patients. Thus, we aimed to uncover the underlying mechanism of chemerin in CP. METHODS: Thirty six CP patients and 25 healthy volunteers were enrolled. Periodontal ligament stem cells (PDLSCs) were isolated from CP patients and healthy ones, respectively. Then, normal PDLSCs or PDLSCs-differentiated osteoblasts were treated with different doses of recombinant human chemerin. RESULTS: Chemerin and inflammatory cytokines, including interleukin-1ß, interleukin-6, and tumor necrosis factor-α, were higher in the GCF and serum of CP patients than healthy ones. Moreover, chemerin was positively correlated with these three inflammatory cytokines, respectively, in CP patients. PDLSCs isolated from CP patients had higher expressions of chemerin and these cytokines than the ones isolated from normal individuals. Furthermore, chemerin dose-dependently increased inflammatory responses and inhibited osteogenic differentiation of PDLSCs. CONCLUSION: Chemerin accelerated inflammatory responses and suppressed osteogenic differentiation of PDLSCs, thus chemerin might sever as a therapeutic target of CP.

Role of ubiquitin-specific protease 5 in the inflammatory response of chronic periodontitis.

BACKGROUND: The systemic inflammatory response caused by chronic periodontitis is a risk factor for multiple diseases. Ubiquitin-specific protease 5 (USP5) is a kind of deubiquitinase which mainly responsible for dissociating unanchored polyubiquitin. However, the functions of USP5 in chronic periodontitis have not been reported. METHODS: Chronic periodontitis patients were recruited, and their periodontal samples were collected. The levels of USP5, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) in gingival crevicular fluid were evaluated by ELISA. The expression of USP5, TNF-α, IL-6, and IL-1ß in human periodontal ligament stem cells (PDLSCs) was estimated by qRT-PCR assay. The activation of STAT3 signaling was examined by Western blot. RESULTS: USP5 was upregulated in the gingival crevicular fluid and gingival tissues of chronic periodontitis patients. USP5 expression was positively correlated with the expression of proinflammatory factors. USP5 knockdown and deubiquitinase inhibitor inhibited LPS-induced inflammatory responses in PDLSCs. Suppressing USP5 inhibited STAT3 signaling in PDLSCs. CONCLUSION: Suppression deubiquitinase USP5 inhibits the inflammatory response of chronic periodontitis by suppressing STAT3 signaling.

Study on the imbalance of M1/M2 macrophage polarization in severe chronic periodontitis.

BACKGROUND: Macrophages commonly exist in two distinct subsets in different microenvironments: classically activated macrophages (M1) and alternatively activated macrophages (M2). The imbalance of M1-M2 macrophage polarization is often related to various diseases or inflammatory states. OBJECTIVE: The purpose of this study was to determine whether there is an imbalance in the expression of M1 and M2 macrophage-related cytokines in severe chronic periodontitis. METHODS: A total of 30 clinical specimens, including severe chronic periodontitis tissues (n= 15) and healthy control tissues (n= 15), were used in this study. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot methods were used to detect the mRNA and protein expression levels of M1 macrophage-related cytokines (inducible nitric oxide synthase (iNOS) and signal transducer and activator of transcription 1 (STAT1)) and M2 macrophage-related cytokines (arginase-1 (Arg-1) and STAT6), respectively. RESULTS: The mRNA and protein expression levels of M1 macrophage-related cytokines (iNOS and STAT1) and M2 macrophage-related cytokines (Arg-1 and STAT6) were significantly increased in severe chronic periodontitis patients. In addition, the ratios of iNOS/Arg-1 and STAT1/STAT6 in the severe chronic periodontitis group were also significantly increased (P< 0.01). CONCLUSION: The imbalance of M1/M2 macrophages exists in the pathogenesis of severe chronic periodontitis, and has a tendency towards M1 polarization. Therefore, maintaining the immune balance of M1/M2 macrophages may be a novel therapeutic alternative for the management of severe chronic 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-1ß, 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.

Effects of a 980 nm Diode Laser as an Adjunct to Nonsurgical Periodontal Therapy on Periodontal Status and Inflammatory Markers in Patients After Myocardial Infarction: A Randomized Controlled Trial.

Objective: The aim of this study was to evaluate the efficacy of diode laser (DL) therapy as an adjunct to nonsurgical periodontal therapy in the treatment of periodontitis in patients after myocardial infarction (MI). Methods: After given permission by Ethics Commission of the Pomeranian Medical University (KB-0012/06/12), 36 patients <65 years of age (mean: 56.3 ± 7.9) with periodontitis, 6 weeks to 6 months after MI were enrolled for the study. The control group (n = 18) received nonsurgical periodontal therapy, whereas the test group (n = 18) received nonsurgical periodontal therapy followed by laser therapy of the periodontal pockets with 980 nm DL, 1 W, continuous wave mode, and 20 sec per tooth side. Procedures were repeated twice at 5-7 day intervals. Clinical periodontal parameters and inflammatory markers in gingival crevicular fluid (GCF) [elastase, aspartate transaminase (AST), alanine transaminase (ALT) and interleukin (IL)-6, proteins], bloodstream [fibrinogen, high-sensitivity CRP (hs-CRP), IL-6, AST and ALT], and lipid fractions (triglycerides, high-density lipoprotein, low-density lipoprotein, and total cholesterol) were measured before treatment, 2 weeks, and 3 months after treatment. Results: The difference between groups in the reduction of periodontal pocket depth (PPD) in pockets ≥7 mm was found to be significant in the test group (p < 0.05). There was also a statistically significant reduction in the volume of GCF and hs-CRP concentration in blood 2 weeks after the completion of treatment in the test group (p < 0.05). Conclusions: Within the limits of this study, it can be concluded that in the nonsurgical treatment of periodontitis with patients after MI, the additional use of DL enables greater reduction of PPD in pockets ≥7 mm. In addition, a faster reduction of GCF volume and hs-CRP was noted in the laser group.

Enamel Matrix Derivative Decreases Pyroptosis-Related Genes in Macrophages.

Background: Pyroptosis is a caspase-dependent catabolic process relevant to periodontal disorders for which inflammation is central to the pathophysiology of the disease. Although enamel matrix derivative (EMD) has been applied to support periodontal regeneration, its capacity to modulate the expression of pyroptosis-related genes remains unknown. Considering EMD has anti-inflammatory properties and pyroptosis is linked to the activation of the inflammasome in chronic periodontitis, the question arises whether EMD could reduce pyroptosis signalling. Methods: To answer this question, primary macrophages obtained from murine bone marrow and RAW 264.7 macrophages were primed with EMD before being challenged by lipopolysaccharide (LPS). Cells were then analysed for pyroptosis-signalling components by gene expression analyses, interleukin-1ß (IL-1ß) immunoassay, and the detection of caspase-1 (CAS1). The release of mitochondrial reactive oxygen species (ROS) was also detected. Results: We report here that EMD, like the inflammasome (NLRP3) and CAS1 specific inhibitors-MCC950 and Ac-YVAD-cmk, respectively-lowered the LPS-induced expression of NLRP3 in primary macrophages (EMD: p = 0.0232; MCC950: p = 0.0426; Ac-YVAD-cmk: p = 0.0317). EMD further reduced the LPS-induced expression of NLRP3 in RAW 264.7 cells (p = 0.0043). There was also a reduction in CAS1 and IL-1ß in RAW 264.7 macrophages on the transcriptional level (p = 0.0598; p = 0.0283; respectively), in IL-1ß protein release (p = 0.0313), and CAS1 activity. Consistently, EMD, like MCC950 and Ac-YVAD-cmk, diminished the ROS release in activated RAW 264.7 cells. In ST2 murine mesenchymal cells, EMD could not be tested because LPS, saliva, and IL-1ß + TNF-α failed to provoke pyroptosis signalling. Conclusion: These findings suggest that EMD is capable of dampening the expression of pyroptosis-related genes in macrophages.

Periodontitis exacerbates endothelial dysfunctions partly via endothelial-mesenchymal transition in streptozotocin-induced diabetes rats.

OBJECTIVES: Periodontal infections are related to the expansion of diabetes cardiovascular problems. However, the pathological process and probable mechanism remain unexplained. This study investigated the impact of periodontitis on streptozotocin (STZ)-induced diabetes rats' carotid artery. METHODS: We randomized 24 Sprague-Dawley (SD) rats into four groups: control, chronic periodontitis (CP), diabetes mellitus (DM), and DM +CP groups. Fasting blood glucose (FBG) and hemoglobin A1c (HBA1c ) were measured to verify the establishment of the DM model. After euthanasia, the maxillary was collected for further studies like hematoxylin-eosin (HE), Masson staining, and micro-computed tomography (micro-CT) analysis. Immunofluorescence (IF) staining was used to detect endothelial-mesenchymal transition (EndMT)-related markers in carotid artery wall. We further used ELISA and quantitative real-time PCR to investigate the effect of high glucose (HG) and Porphyromonas gingivalis lipopolysaccharide (P.g-LPS) on human umbilical vein endothelial cells (HUVECs). RESULTS: Compared with DM and CP groups, bone resorption and pathological changes of the vascular wall were the most serious in the DM+CP group. The vascular wall of the DM+CP group had a higher level of interleukin (IL)-6 and vascular cell adhesion molecule 1 (VCAM-1). The carotid artery vascular wall of the DM+CP group contained more cells that expressed both mesenchymal and endothelial cell markers, along with elevated transcription factor levels. Furthermore, P.g-LPS and HG upregulated the inflammatory cytokines expression and caused phenotypic changes of HUVECs in vitro. CONCLUSION: Periodontitis exacerbates endothelial dysfunctions partly via endothelial-mesenchymal transition in STZ-induced diabetes rats.

The role of long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (NEAT1) in chronic periodontitis progression.

Long non-coding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) is a novel pro-inflammatory factor in severe human diseases. Since inflammatory plays important roles in periodontitis progression, we aimed to explore the role of NEAT1 in chronic periodontitis (CP) in vitro. We established a periodontitis cell model was established by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS)-induced periodontal ligament cells (PDLCs). Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to detect the expression of NEAT1, microRNA (miR)-200c-3p, and tumor necrosis factor receptor-associated factor 6 (TRAF6). Cell viability, inflammatory factors, and protein expression of Bcl-2, Bax, and TRAF6 were analyzed by MTT, enzyme-linked immunosorbent assay, and Western blot. The target relationships among NEAT1, miR-200c-3p, and TRAF6 were predicted by the StarBase/TargetScan software, and further validated by dual-luciferase reporter assay. In this research, NEAT1 is up-regulated in CP tissues and periodontitis model group. Silencing of NEAT1 and over-expression of miR-200c-3p enhanced cell viability and repressed apoptosis in the periodontitis model group. NEAT1 targets miR-200c-3p, and miR-200c-3p further targets TRAF6. MiR-200c-3p inhibitor or over-expression of TRAF6 reversed the promoting effect of NEAT1 knockdown on cell viability, and the inhibiting effects on inflammatory cytokines and cell apoptosis. Consequently, the silencing of NEAT1 inhibits inflammation and apoptosis via targeting miR-200c-3p/TRAF6 axis, thereby contributing to alleviate the progression of CP. This finding could provide an underlying target for the treatment of CP.

Role of PG0192 and PG0193 in the modulation of pro-inflammatory cytokines in macrophages in response to Porphyromonas gingivalis.

Porphyromonas gingivalis is the main pathogen of chronic periodontitis. However, the specific mechanisms through which P. gingivalis induces immune and inflammatory responses in periodontitis have not been completely elucidated. In this study, we investigated the effects of the P. gingivalis outer membrane protein OmpH (encoded by PG0192 and PG0193) on interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) expression in macrophages to assess the pro-inflammatory cytokine responses. A PG0192-PG0193 deletion mutant strain and a com△PG0192-0193 strain were constructed. Furthermore, rOmpH-1 and rOmpH-2 encoded by PG0192 and PG0193, respectively, were cloned, expressed, and purified for subsequent experiments. Notably, the expression of IL-6 and TNF-α at mRNA and protein levels was downregulated upon treatment of macrophages with the PG0192-PG0193 deletion mutant strain, whereas treatment of macrophages with P. gingivalis W83 co-incubated with rOmpH-1 or rOmpH-2 upregulated IL-6 and TNF-α mRNA levels. The addition of C5aR antagonist blocked this induction. Overall, our findings provided important insights into the roles of PG0192 and PG0193 for promoting IL-6 and TNF-α expression in macrophages exposed to P. gingivalis and revealed the involvement of C5aR in the pro-inflammatory response.

Investigation of the relationship between periodontal and systemic inflammation in children with Sickle Cell Disease: A case- control study.

Periodontal diseases are chronic inflammatory diseases and tissue destruction increases with oxidative stress in periodontal tissues. Periodontal diseases are associated with systemic diseases such as diabetes, cardio-vascular diseases and rheumatoid arthritis by means of systemic inflammation. Sickle cell disease (SCD) is a chronic inflammatory disease in which vaso-occlusive crisis and endothelial dysfunction are present. It is not known whether the chronic systemic inflammation seen in SCD affect periodontal tissues. The aim of this study was to investigate the relationship between periodontal and systemic inflammation in children with SCD. Forty-three children with SCD and 43 healthy children were included in the study. Physical, dental and periodontal statuses were examined, blood and saliva samples were taken. Levels of pro-inflammatory and oxidative stress mediators in serum and saliva were evaluated. The periodontal findings of the groups were similar. The majority of the subjects in both groups had gingival inflammation. In SCD group, significantly higher serum high sensitive C-reactive protein (Hs-CRP), interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, total oxidant status (TOS), nitric oxide (NO) and salivary IL-6 were observed (p < 0.05). There were positive correlations between salivary IL-6 levels and serum Hs-CRP levels (r = 0.303, p < 0.05). In addition; it was determined that salivary IL-6, TNF-α and NO levels were increased 3-6 times in children with a history of painful crisis or acute chest syndrome compared to children who had never had a painful crisis or acute chest syndrome. Although, observed oral health status was similar in both groups, salivary cytokine levels were increased in children with SCD. The higher salivary cytokine levels may be associated with chronic systemic inflammation and vaso-occlusion observed in children with SCD.

Trim14 promotes osteoclastogenesis and noncanonical NF-κB activation by targeting p100/p52 in chronic periodontitis.

BACKGROUND: Periodontitis disease infection initiates host immune response, and alveolar bone damage is a hallmark of periodontitis. Bone damage occurs due to changes in osteoclast activity in response to local inflammation. Nuclear factor κB (NF-κB) signaling is essential for inflammatory responses and plays a pivotal role in osteoclast formation and activation. Tripartite motif 14 (Trim14) is a crucial regulator of the noncanonical NF-κB signaling. Here, we investigated the role of Trim14 in chronic periodontitis. METHODS: The development of immune cells and osteoclast formation was evaluated with flow cytometry, qRT-PCR, and histochemical staining. Proinflammatory cytokines were checked by ELISA and qRT-PCR. Protein expression was determined by immunoblotting. Also, the cemento-enamel junction-alveolar bone crest distance was evaluated in the mouse model. RESULTS: Development of innate and adaptive cells was not impaired from the deletion of Trim14. However, the genetic loss of Trim14 remarkably suppressed RANKL-induced osteoclastogenesis, without affecting TLR-induced proinflammatory cytokines except for Il-23a expression. The Trim14 deletion also suppressed the activation of noncanonical NF-κB signaling by targeting p100/p52. Importantly, the deletion of NIK diminished the effects of Trim14 on the inflammatory responses in vivo on chronic periodontitis responses. CONCLUSION: TRIM14 may be a positive regulator to promote osteoclastogenesis and proinflammatory cytokine secretion.

Abnormal hsa_circ_0003948 expression affects chronic periodontitis development by regulating miR-144-3p/NR2F2/PTEN signaling.

BACKGROUND AND OBJECTIVE: This study aimed to investigate the correlation between chronic periodontitis (CP) and abnormal circular RNA (circRNA) expression and to identify the role of hsa_circ_0003948 in the progression of CP. METHODS: Next-generation sequencing was utilized to investigate abnormal expression of circRNA in gingival tissues from CP patients and healthy control subjects. Bioinformatics and luciferase reporting analyses were used to clarify the interactive relationship among circRNA, miRNA, and mRNA. Periodontal ligament cells (PDLCs) were employed to analyze proliferation and apoptosis after lipopolysaccharide (LPS) treatment using the cell counting kit 8 (CCK8) assay and flow cytometry detection. RESULTS: High-throughput sequencing and RT-qPCR analyses confirmed that hsa_circ_0003948 expression decreased dramatically in gingival samples of CP patients. Overexpression of hsa_circ_0003948 alleviated LPS-induced PDLC injury by regulating NR2F2/PTEN signaling. The miR-144-3p and NR2F2 were determined to be hsa_circ_0003948 downstream targets. NR2F2 downregulation or miR-144-3p overexpression reversed the protective effect of hsa_circ_0003948 in PDLCs after treatment with LPS. Upregulation of NR2F2 reversed the inhibitory effect of miR-144-3p on surviving PDLCs after LPS treatment. CONCLUSION: Overexpression of hsa_circ_0003948 exerts a protective effect in CP via miR-144-3p/NR2F2/PTEN signaling regulation.