Chronic periodontitis, inflammatory cytokines, and interrelationship with other chronic diseases

LPS stimulates gingival fibroblasts to express PD-L1 via the p38 pathway under periodontal inflammatory conditions

OBJECTIVE

The overall aim of this research was to investigate the differences in the expression of programmed death ligand 1 (PD-L1) in human gingival fibroblasts (HGFs) between a periodontal healthy group and a periodontal inflammatory group. and explore the possible mechanism involved.

METHODS

Differences in PD-L1 mRNA and protein expression in HGFs from a periodontal healthy group and a periodontal inflammatory group were examined by qPCR and western blotting, respectively, and were further tested after lipopolysaccharide (LPS) stimulation in both groups. The effects of a p38 pathway inhibitor on the changes in p38 phosphorylation levels and PD-L1 expression after LPS stimulation were investigated in both groups.

RESULTS

PD-L1 mRNA and protein levels in HGFs in the periodontal inflammatory group were significantly higher than those in the periodontal healthy group (p < 0.05). After 10 μg/mL LPS stimulation, PD-L1 mRNA levels in HGFs from both groups increased significantly (p < 0.05), peaking at 4 h, and the peak was significantly higher in the periodontal inflammatory group than in the periodontal healthy group (p < 0.05). However, PD-L1 protein expression was upregulated only in the inflammatory group (p < 0.05). Inhibition of the p38 pathway in HGFs decreased p38 phosphorylation in both groups (p < 0.05) but this treatment reversed the LPS-induced increase in PD-L1 mRNA and protein levels only in the inflammatory group (p < 0.05).

CONCLUSION

In the periodontal inflammatory state, the expression of PD-L1 in HGFs is more easily activated, and may be influenced by the p38 pathway.

Sclerostin regulation: a promising therapy for periodontitis by modulating alveolar bone

Periodontitis is one of the most prevalent epidemics affecting human health and life recently, and exploration of the pathogenesis and treatment of periodontitis has been valued by scholars. In recent years, sclerostin, a new factor on bone resorption and reconstruction caused by inflammation and mechanical stimulation, has been a research hotspot. This article summarizes the researches on sclerostin in periodontitis development in recent years. Among them, sclerostin has been shown to be a critical negative regulator of bone formation, thereby inhibiting bone remodeling in periodontitis development, and is closely associated with tooth movement. Besides, evidence indicates that the removal of sclerostin seems to reasonably protect the alveolar bone from resorption. Regulation of sclerostin expression is a novel, promising treatment for periodontitis and addresses several complications seen with traditional therapies; accordingly, many drugs with similar mechanisms have emerged. Moreover, the application prospect of sclerostin in periodontal therapy combined with orthodontic treatment is another promising approach. There are also a lot of drugs that regulate sclerostin. Anti-sclerostin antibody (Scl-Ab) is the most direct one that inhibits bone resorption caused by sclerostin. At present, drugs that inhibit the expression of sclerostin have been applied to the treatment of diseases such as multiple myeloma and osteoporosis. Therefore, the application of sclerostin in the oral field is just around the corner, which provides a new therapeutic bone regulation strategy in oral and general health.

Surgical Treatment of Sialolithiasis Leads to Improvement in the Complete Blood Count

Simple Summary

Sialolithiasis is a disease in which inflammation and infection are caused in a salivary gland and its duct secretion system due to a formation of a sialolith (salivary stone) in the gland. Anemia of inflammation is a well described pathology where chronic inflammation causes a reduction in the red blood cell count is. In this study, we examined the complete blood count results of patients who underwent surgical removal of a sialolith and found that removal of the stone and cessation of the symptoms lead to an improvement in the complete blood count results. We believe that the improvement in blood count values after surgery is due to resolution of the anemia of inflammation. To our knowledge, this is the first report about the relationship between surgery for removal of a salivary stone and improvement in the wellbeing of patient expressed by blood count values.

Abstract

Sialolithiasis is a chronic disease in which a sialolith (salivary stone) causes recurrent inflammation of the affected salivary gland. Anemia of inflammation is a well-described pathology in which a chronic inflammatory disease leads to a reduction in the red blood cell count, hemoglobin and hematocrit values. In this retrospective cohort study, we aim to find whether removal of the sialolith and alleviation of the inflammation affect the complete blood count results. We examined data regarding forty-nine patients who underwent surgery for the removal of a submandibular gland sialolith using the duct-stretching technique. Complete blood counts two years before and after the surgical procedure were collected. The average pre-procedure and post-procedure values were calculated for each patient to establish the average blood profile. The pre- and post-procedure values were compared to evaluate the effect of the surgical treatment on the blood profile. We found that the average blood count values for patients with sialolithiasis were towards the lower end of the normal range. Post-surgery, a significant increase in hematocrit, hemoglobin and red blood cell count was observed, which was more pronounced in the older age group and in patients with co-morbidities. We conclude that sialolith removal surgery is associated with significant improvement in the complete blood count values, especially in the elderly and in patients and with co-morbidities. The speculated pathogenesis is relative anemia of inflammation.

Intelligent Prediction and Optimization Algorithm for Chronic Disease Rehabilitation in Sports Using Big Data

This paper investigates chronic diseases in the older population in the Chinese province of Henan and analyzes the rehabilitation needs and the current supply of related services in different levels of medical and elderly care institutions. We explore the fundamental causes for the diversified needs and insufficient supply of chronic disease patients in professional medical services and daily care. Using big data and deep learning (DL) in the sports domain, we propose a novel and intelligent prediction system for chronic diseases. Our model explores effective sinking methods of high-quality medical resources, training and guidance practices, assistance and guidance measures, and the ability to improve the grassroots services so that more chronically ill populations can stay in the community family as long as possible. In such an environment, they can receive cheap, safe, and suitable services. It can also lead to further improvement in constructing the government's regional medical rehabilitation care service system and can formulate long-term care relevant compensation policies.

Phenotypes, roles, and modulation of regulatory lymphocytes in periodontitis and its associated systemic diseases

Periodontitis is a common chronic inflammatory disease that can result in tooth loss and poses a risk to systemic health. Lymphocytes play important roles in periodontitis through multiple mechanisms. Regulatory lymphocytes including regulatory B cells (Bregs) and T cells (Tregs) are the main immunosuppressive cells that maintain immune homeostasis, and are critical to our understanding of the pathogenesis of periodontitis and the development of effective treatments. In this review, we discuss the phenotypes, roles, and modulating strategies of regulatory lymphocytes including Bregs and Tregs in periodontitis and frequently cooccurring inflammatory diseases such as rheumatoid arthritis, Alzheimer disease, diabetes mellitus, and stroke. The current evidence suggests that restoring immune balance through therapeutic targeting of regulatory lymphocytes is a promising strategy for the treatment of periodontitis and other systemic inflammatory diseases.

The intergenerational interplay of adversity on salivary inflammation in young children and caregivers

Systemic inflammation links exposure to early childhood adversity to later disease. The associations among adversity and disease risk might in part operate through poor oral hygiene and subsequent periodontal inflammation, which can be measured in saliva. Few studies, however, have examined the association between adversity and salivary inflammation in young children. Further, there is a dearth of literature investigating adverse experiences and salivary inflammation in children and caregivers together, limiting our understanding of the intergenerational, dual effects of adversity on inflammation for both members of the caregiver-child dyad. This study tested child and caregiver adversity and their associations with an inflammatory composite (i.e., IL-6, IL-1β, IL-8, TNF-α) and CRP in 93 preschool-age children and their caregivers. Caregivers reported on their child's experiences of adversity, as well as on their own adverse experiences, using a comprehensive questionnaire synthesized from previous checklists for complete coverage of possible adverse events. Results showed that caregivers' salivary inflammatory markers (i.e., IL-6, IL-1β, IL-8, TNF-α, and CRP) were not significantly correlated with the same five inflammatory markers in children's saliva. Among children, adversity was associated with significantly higher levels of the inflammatory composite, though not CRP. This association was amplified among children whose caregivers also experienced more adversity during adulthood. Among caregivers, childhood adversity and adulthood adversity were each independently associated with significantly higher levels of the inflammatory composite and CRP. The association between caregivers' own childhood adversity and inflammation was amplified among caregivers whose children also experienced more adversity during their childhoods. These findings provide preliminary evidence for the possible dual role of young children's and caregivers' adverse experiences in contributing to salivary inflammation for both members of the dyad, suggesting possible implications for systemic inflammation and future disease.

Application value of combination therapy of periodontal curettage and root planing on moderate-to-severe chronic periodontitis in patients with type 2 diabetes

BACKGROUND

Our study attempted to observe the value of periodontal curettage combined with root planing on moderate-to-severe chronic periodontitis in patients with type 2 diabetes.

METHODS

There involved 72 patients with type 2 diabetes mellitus complicated with moderate-to-severe chronic periodontitis who were diagnosed and treated in our hospital from January 2019 to December 2019. The patients enrolled were randomly divided into four groups using a computer-generated table: root planing and periodontal curettage combined group (n = 18), root planning group (n = 18), periodontal curettage group (n = 18) and cleansing group (n = 18). Blood glucose, plaque index (PI), gingival index (GI), probing depth (PD), attachment loss (AL), serum levels of inflammatory factors (Tumor Necrosis Factor Alpha [TNF- α] and hypersensitive C-reactive protein [hs-CRP]) were observed before and after treatment. The collecting dates were analyzed by the chi-square χ 2 test, repeated measurement analysis of variance, or t-test according to different data types and research objectives.

RESULTS

Before treatment, there was no significant difference in PI, GI, PD and AL among the four groups (P> 0.05), while after 3-month treatment, the levels of PI, GI, PD and AL in the combined group were lower than those in the root planing group, periodontal curettage group and cleansing group, with both root planing group and periodontal curettage group significantly lower than cleansing group (P< 0.05). The fasting blood glucose, 2-h postprandial blood glucose and glycosylated hemoglobin in the combined group, root planing group, periodontal curettage group and cleansing group were significantly lower than those before treatment (P < 0.05). Before treatment, there was no significant difference in TNF- α and hs-CRP among the four groups (P> 0.05), but the levels of TNF- α and hs-CRP in the four groups decreased significantly after 3-month treatment (P< 0.05). The levels of TNF- α and hs-CRP in the combined group were lower than those in the root planing group, periodontal curettage group and cleansing group, and those in the root planing group and periodontal curettage group were significantly lower than those in the cleansing group (P< 0.05).

CONCLUSION

The combination therapy of periodontal curettage and root planing exerted beneficial effects on moderate-to-severe chronic periodontitis in patients with type 2 diabetes mellitus, which holds the potential to maintain the level of blood glucose and improve the quality of life of the patients.

Molecular subgroup of periodontitis revealed by integrated analysis of the microbiome and metabolome in a cross-sectional observational study

Background: Periodontitis (PT) is a multifactorial, chronic inflammatory disease that can have heterogeneous clinical presentations. The oral microbiome and its metabolites have been implicated as the causes and regulators of PT pathogenesis. In this study, we assessed the oral microbiome and its metabolome in PT patients to clarify the interactions between the microbiome and its metabolites.Methods: A total of 112 subjects were recruited. Buccal and supragingival samples were collected for microbiome analysis. Saliva samples were collected for metabolomic analyses. Microbiome and metabolome data were analyzed and further integrated for combined analysis using various bioinformatics approaches.Results: Oral metabolomic analysis identified 28 metabolites distinguishing the healthy (H) and PT groups. PT group were further clustered into two subgroups (PT_G1 and PT_G2) depending on metabolite profiles. Oral microbiome analysis revealed discriminatory bacterial species in the H, PT_G1, and PT_G2 microbiota. Interestingly, PT_G2 had significantly higher concentration of short chain fatty acids and higher abundance of pathogenic bacteria. Integrated analysis of the microbiome and metabolome showed close association.Conclusion: Our results provide evidence of a close interplay between the oral microbiome and metabolome. Multi-omics approach including microbiome and microbe-associated metabolites may serve as diagnostic biomarkers and enhance treatment prediction in periodontal disease.

Activated STAT3 signaling pathway by ligature-induced periodontitis could contribute to neuroinflammation and cognitive impairment in rats

Background

Increasing evidence suggests a causal link between periodontitis and cognitive disorders. Systemic inflammation initiated by periodontitis may mediate the development of cognitive impairment. Our study aims to investigate the effect of ligature-induced periodontitis on cognitive function and the role of signal transducers and activators of transcription 3 (STAT3) in this process.

Materials and methods

Ligature-induced periodontitis was established, and the rats were treated intraperitoneally with/without the pSTAT3 inhibitor cryptotanshinone (CTS). Alveolar bone resorption and periodontal inflammation were detected by micro-computed tomography analysis and histopathological evaluation. Locomotor activity and cognitive function were evaluated by the open field test and the Morris water maze test, respectively. The activation of microglia and astrocytes in the hippocampus and cortex was assessed by immunohistochemistry (IHC). The expression of interleukins (IL-1β, IL-6, IL-8, IL-21) in both the periphery and cortex was evaluated by RT-PCR and ELISA. The expression of TLR/NF-κB and ROS cascades was evaluated by RT-PCR. The expression of pSTAT3 and the activation of the STAT3 signaling pathway (JAK2, STAT3, and pSTAT3) in the periodontal tissue and cortex were assessed by IHC and Western blot. The expression of amyloid precursor protein (APP) and its key secretases was evaluated by RT-PCR. The level of amyloid β-protein (Aβ) and the ratio of Aβ1-40/1-42 were measured via ELISA in the plasma and cortex while IHC was used to detect the level of Aβ1-42 in the brain.

Results

In periodontal ligature rats, significant alveolar bone resorption and local inflammatory cell infiltration were present. Apparent increases in inflammatory cytokines (IL-1β, IL-6, IL-8, and IL-21) were detected in peripherial blood and brain. Additionally, spatial learning and memory ability was impaired, while locomotor activity was not affected. Activated microglia and astrocytes were found in the cortex and hippocampus, presenting as enlarged cell bodies and irregular protrusions. Levels of TLR/NF-kB, PPAR and ROS were altered. The STAT3 signaling pathway was activated in both the periodontal tissue and cortex, and the processing of APP by β- and γ-secretases was promoted. The changes mentioned above could be relieved by the pSTAT3 inhibitor CTS.

Conclusions

Ligature-induced periodontitis in rats resulted in systemic inflammation and further abnormal APP processing, leading to cognitive impairments. In this progress, the activation of the STAT3 signaling pathway may play an important role by increasing inflammatory load and promoting neuroinflammation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02071-9.

Thermoresponsive Hydrogel-Based Local Delivery of Simvastatin for the Treatment of Periodontitis

Except for routine scaling and root planing, there are few effective nonsurgical therapeutic interventions for periodontitis and associated alveolar bone loss. Simvastatin (SIM), one of the 3-hydroxy-3-methylglutaryl-cosenzyme A reductase inhibitors, which is known for its capacity as a lipid-lowering medication, has been proven to be an effective anti-inflammatory and bone anabolic agent that has shown promising benefits in mitigating periodontal bone loss. The local delivery of SIM into the periodontal pocket, however, has been challenging due to SIM's poor water solubility and its lack of osteotropicity. To overcome these issues, we report a novel SIM formulation of a thermoresponsive, osteotropic, injectable hydrogel (PF127) based on pyrophosphorolated pluronic F127 (F127-PPi). After mixing F127-PPi with F127 at a 1:1 ratio, the resulting PF127 was used to dissolve free SIM to generate the SIM-loaded formulation. The thermoresponsive hydrogel's rheologic behavior, erosion and SIM release kinetics, osteotropic property, and biocompatibility were evaluated in vitro. The therapeutic efficacy of SIM-loaded PF127 hydrogel on periodontal bone preservation and inflammation resolution was validated in a ligature-induced periodontitis rat model. Given that SIM is already an approved medication for hyperlipidemia, the data presented here support the translational potential of the SIM-loaded PF127 hydrogel for better clinical management of periodontitis and associated pathologies.

Effect of periodontal therapy on COPD outcomes: a systematic review

Background

Latest evidence suggests that periodontitis is prevalent among patients with chronic obstructive pulmonary disease (COPD), while recent studies have also reported a potential benefit of periodontal treatment on several COPD outcomes. This systematic review aims to determine the impact of periodontal treatment on exacerbation rate, lung function and quality of life of COPD patients.

Methods

A systematic search of electronic databases of PubMed, Scopus, Virtual Health Library, ScienceDirect, Wiley Online Library, Web of Science, ProQuest Dissertation and Theses Global and Google Scholar was conducted. Search restricted to studies involving human subjects which were published from January 2000 to March 2020 in English language. Distiller Systematic Review software was used for data management. Risk of bias was assessed using Risk of Bias 2 (RoB2) and Risk of Bias for non-randomized studies of intervention (ROBINS-I) tools. Overall quality of evidence was judged based on Grading of Recommendations Assessment, Development and Evaluation working group methodology.

Results

Out of 1442 articles retrieved, 7 full text articles were included in the review. Limited evidence suggests that periodontal treatment in patients with COPD and periodontitis is associated with reduced exacerbation frequency and a slower lung function decline rate, while its effects on quality of life remain unclear. In addition, periodontal treatment in COPD is associated with lower hospitalization rates and reduced all-cause mortality. Significant methodological differences were noted amongst included studies, while very low-to-moderate overall quality of evidence was demonstrated.

Conclusions

Although it is reasonable to advise COPD patients not to neglect their dental health, further studies are warranted to determine the role of periodontal therapy on COPD clinical outcomes.

Trial Registration: PROSPERO 2020 (CRD42020158481). https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020158481

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01429-2.

Influence of Materials Properties on Bio-Physical Features and Effectiveness of 3D-Scaffolds for Periodontal Regeneration

Periodontal diseases are multifactorial disorders, mainly due to severe infections and inflammation which affect the tissues (i.e., gum and dental bone) that support and surround the teeth. These pathologies are characterized by bleeding gums, pain, bad breath and, in more severe forms, can lead to the detachment of gum from teeth, causing their loss. To date it is estimated that severe periodontal diseases affect around 10% of the population worldwide thus making necessary the development of effective treatments able to both reduce the infections and inflammation in injured sites and improve the regeneration of damaged tissues. In this scenario, the use of 3D scaffolds can play a pivotal role by providing an effective platform for drugs, nanosystems, growth factors, stem cells, etc., improving the effectiveness of therapies and reducing their systemic side effects. The aim of this review is to describe the recent progress in periodontal regeneration, highlighting the influence of materials' properties used to realize three-dimensional (3D)-scaffolds, their bio-physical characteristics and their ability to provide a biocompatible platform able to embed nanosystems.

Is sexual dysfunction associated with periodontal status in perimenopausal women?: A pilot study

OBJECTIVE

The current study aimed to investigate the possible relationship between periodontal status and sexual dysfunction in perimenopausal women.

MATERIALS AND METHODS

This study was conducted on 106 participants. After the evaluation of the sexual functioning of participants with the Female Sexual Function Index (FSFI), their periodontal status and decayed-missing-filled teeth (DMFT) were assessed using appropriate indexes and obtained results were recorded for comparisons. Participants were divided into two groups by the periodontal status. Patients with periodontitis were grouped by the stage and the extent of the disease. Besides, participants were grouped according to the bleeding on probing (BOP) ratios for more detailed analyses.

RESULTS

A negative significant correlation was observed between total FSFI scores and each of the clinical periodontal parameters. Total FSFI scores and the scores of arousal, lubrication, orgasm, satisfaction, and pain domains were significantly lower in periodontitis patients (p < .05). When the patients were grouped as having localized or generalized periodontitis or whether they had stage-I, -II, and -III periodontitis, no statistically significant differences were observed in the distribution of general sexual dysfunction parameters across the groups (p > .05).

CONCLUSION

Periodontal status in perimenopausal women may be associated with sexual dysfunction.

Potential biomarkers reflecting inflammation in patients with severe periodontitis: Fractalkine (CX3CL1) and its receptor (CX3CR1)

OBJECTIVE

The aim of this study was to determine differences in GCF and serum levels of fractalkine/CX3CL1 and its receptor/ CX3CR1 between the patients with stage III/grade B periodontitis and periodontally healthy subjects.

BACKGROUND

Fractalkine (CX3CL1), the only member of CX3C chemokine family, is involved in the pathogenesis of several systemic inflammatory diseases' disorders including rheumatoid arthritis, cardiovascular diseases, tonsillitis, and diabetes mellitus. It has critical functions in inflammatory cell migration, adhesion, and proliferation.

METHODS

20 stage III/grade B periodontitis (P) and 20 healthy individuals (control; C) were included in this clinical study (all never smokers and systemically healthy). Clinical periodontal parameters were measured. Serum and GCF levels of CX3CL1, CX3CR1, and IL-1β were quantified by enzyme-linked immunosorbent assay and reported as total amounts and concentration.

RESULTS

The GCF concentrations and also total amount of CX3CL1, CX3CR1, and IL-1β were statistically significantly higher in the patients with periodontitis compared with control group (P < 0.05). CX3CL1, CX3CR1, and IL-1β levels in the GCF were significantly and positively correlated with all the clinical periodontal parameters (PI, PPD, BOP, and CAL; P < 0.01, P < 0.05). There was a significant correlation between IL-1β, CX3CL1, and CX3CR1 concentrations in the GCF (respectively; r = 0.838 and r = 0.874, P < 0.01).

CONCLUSION

Fractalkine and its receptor may play role in mechanisms through the regulation of inflammation or on the pathogenesis of periodontal disease.

Gingival crevicular fluid infiltrating CD14+ monocytes promote inflammation in periodontitis

Periodontitis is a condition that occurs because of inflammation-mediated tissue degeneration. Many studies have been conducted to identify inflammatory molecules in periodontitis, but the well-defined role of cells from the immune system in the progression of periodontitis as well as in gingival tissue degeneration has not been appropriately established. The objective of the present study was to characterize the monocytes isolated from the gingival crevicular fluid (GCF) in patients with periodontitis. GCF was obtained from periodontitis patients and healthy controls. Cytokine levels of CCL2 were evaluated by ELISA in GCF samples. CD14+ monocytes were separated using magnetic sorting from GCF. RT-qPCR was performed to assess the gene expression. Cytometric bead array analysis was performed to analyze the levels of cytokines and chemokines in the secretome of cells. CD14+ monocytes from GCF secreted higher levels of CCL2 and showed elevated expression of genes responsible for monocyte migration. Additionally, upon lipopolysaccharide stimulation, these monocytes secreted higher levels of inflammatory cytokines and chemokines. This investigation aids in understanding the inflammatory microenvironment of periodontitis by characterizing GCF in terms of infiltrated CD14+ monocytes, cytokines, and molecules secreted by these monocytes, which are specific for cellular differentiation.

Porphyromonas gingivalis lipopolysaccharide induces interleukin-6 and c-c motif chemokine ligand 2 expression in cultured hCMEC/D3 human brain microvascular endothelial cells

OBJECTIVE

This paper describes the effect of Porphyromonas gingivalis (P gingivalis) lipopolysaccharide (LPS) on the expression of interleukin-6 (IL-6) and C-C motif chemokine ligand 2 (CCL2) in cultured hCMEC/D3 human brain microvascular endothelial cells.

BACKGROUND

P gingivalis is one of the important pathogens in periodontitis, and periodontitis is a risk factor for brain disorders including cerebrovascular diseases and Alzheimer's disease. However, the mechanisms underlying the pathogenesis of P gingivalis-mediated brain diseases are incompletely understood. Effects of P gingivalis LPS on brain endothelial cells are not known well.

METHODS

The hCMEC/D3 human brain microvascular endothelial cells were cultured and treated with P gingivalis LPS. The expression of IL-6 and CCL2 mRNA and protein was examined using quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Effect of inhibitors of Toll-like receptor (TLR) 2, TLR4, nuclear factor-κB (NF-κB), p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) was also investigated. Phosphorylation of NF-κB p65, p38 MAPK and JNK was examined using Western blotting.

RESULTS

P gingivalis LPS-induced mRNA and protein expression of IL-6 and CCL2 in hCMEC/D3 cells in a concentration-dependent manner at the concentration of 0.5-50 µg/mL. Maximal mRNA expression of IL-6 and CCL2 was found 2 and 4 hours after stimulation, respectively. Induction of IL-6 and CCL2 by P gingivalis LPS was almost completely inhibited by pretreatment of cells with TLR4 inhibitor but not by TLR2 inhibitor. Treatment of cells with P gingivalis LPS for up to 2 hours induced phosphorylation of NF-κB p65, p38 MAPK and JNK. IL-6 induction was decreased by pretreatment of cells with NF-κB inhibitor SN50 or p38 MAPK inhibitor SB203580, while CCL2 induction was reduced by SN50 or JNK inhibitor SP600125.

CONCLUSIONS

IL-6 and CCL2 produced upon P gingivalis LPS stimulation may contribute to the inflammatory reactions in brain endothelial cells and subsequent neurological disorders such as cerebrovascular and Alzheimer's diseases.

Knockdown of MALAT1 Inhibits the Progression of Chronic Periodontitis via Targeting miR-769-5p/HIF3A Axis

Purpose

Chronic periodontitis (CP) is a long-lasting inflammatory disease that seriously affects oral health. This study is aimed at investigating the regulatory mechanism of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in CP.

Methods

Primary human periodontal ligament cells (PDLCs) were treated with P. gingivalis lipopolysaccharide (LPS) to establish a CP model. Quantitative real-time PCR (qRT-PCR) was used to measure the expression of MALAT1 and miR-769-5p in gingival tissues of patients with CP and LPS-treated PDLCs. Cell viability was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of inflammatory cytokines. The protein levels of caspase-3, Bax, Bcl-2, and hypoxia-inducible factor (HIF) 3A were determined by western blot assay. Dual-luciferase reporter (DLR) assay was applied to validate the target relationships between miR-769-5p and MALAT1/HIF3A.

Results

The expression of MALAT1 and HIF3A was enhanced, and the expression of miR-769-5p was reduced in gingival tissues of patients with CP and LPS-treated PDLCs. MALAT1 knockdown promoted cell viability and inhibited inflammation and cell apoptosis in LPS-treated PDLCs. MALAT1 targeted miR-769-5p and negatively regulated miR-769-5p expression. miR-769-5p overexpression promoted cell viability and inhibited inflammation and cell apoptosis in LPS-treated PDLCs. Besides, miR-769-5p targeted HIF3A and negatively modulated HIF3A expression. Both miR-769-5p inhibition and HIF3A overexpression reversed the inhibitory effects of MALAT1 silencing on LPS-induced PDLC injury in vitro.

Conclusion

MALAT1 knockdown attenuated LPS-induced PDLC injury via regulating the miR-769-5p/HIF3A axis, which may supply a new target for CP treatment.

Anti-inflammatory effect of IL-1ra-loaded dextran/PLGA microspheres on Porphyromonas gingivalis lipopolysaccharide-stimulated macrophages in vitro and in vivo in a rat model of periodontitis

Periodontitis is a multifactorial chronic infectious disease leading to a host immune response involving inflammatory cytokines, especially IL-1β, which is the main reason for further developing this disease. IL-1 receptor antagonist (IL-1ra) binds IL-1 receptor, inhibiting IL-1β signaling and reducing the levels of other cytokines closely related to periodontitis, such as IL-6 and TNF-α. Therefore, the use of IL-1ra to inhibit periodontitis development in a system, ensuring its sustained release, might be an effective way to combat this disease. Hence, in this study, a novel IL-1ra-loaded dextran/PLGA microsphere was developed to allow the sustained release of IL-1ra and enhance the anti-inflammatory properties. Therefore, this study's purposes were to develop a novel periodontal treatment for inhibition and treatment of periodontitis and evaluate the sustained-release effect and anti-inflammatory properties of IL-1ra-loaded dextran/PLGA microspheres in vitro by cell experiments and in vivo by animal experiments. The results showed that IL-1ra-loaded dextran/PLGA microspheres were non-toxic both in vitro and in vivo and could be used as a safe and effective treatment. In addition, these microspheres could significantly prolong the half-life of IL-1ra drug, exerting a useful anti-inflammatory effect in macrophages stimulated with P. gingivalis lipopolysaccharide and in rats with periodontitis. In conclusion, IL-1ra-loaded dextran/PLGA microsphere might be a useful tool to combat periodontal disease.

Stromal cell-derived factor-1/Exendin-4 cotherapy facilitates the proliferation, migration and osteogenic differentiation of human periodontal ligament stem cells in vitro and promotes periodontal bone regeneration in vivo

Objectives

Stromal cell‐derived factor‐1 (SDF‐1) actively directs endogenous cell homing. Exendin‐4 (EX‐4) promotes stem cell osteogenic differentiation. Studies revealed that EX‐4 strengthened SDF‐1‐mediated stem cell migration. However, the effects of SDF‐1 and EX‐4 on periodontal ligament stem cells (PDLSCs) and bone regeneration have not been investigated. In this study, we aimed to evaluate the effects of SDF‐1/EX‐4 cotherapy on PDLSCs in vitro and periodontal bone regeneration in vivo.

Methods

Cell‐counting kit‐8 (CCK8), transwell assay, qRT‐PCR and western blot were used to determine the effects and mechanism of SDF‐1/EX‐4 cotherapy on PDLSCs in vitro. A rat periodontal bone defect model was developed to evaluate the effects of topical application of SDF‐1 and systemic injection of EX‐4 on endogenous cell recruitment, osteoclastogenesis and bone regeneration in vivo.

Results

SDF‐1/EX‐4 cotherapy had additive effects on PDLSC proliferation, migration, alkaline phosphatase (ALP) activity, mineral deposition and osteogenesis‐related gene expression compared to SDF‐1 or EX‐4 in vitro. Pretreatment with ERK inhibitor U0126 blocked SDF‐1/EX‐4 cotherapy induced ERK signal activation and PDLSC proliferation. SDF‐1/EX‐4 cotherapy significantly promoted new bone formation, recruited more CXCR4⁺ cells and CD90⁺/CD34^‐ stromal cells to the defects, enhanced early‐stage osteoclastogenesis and osteogenesis‐related markers expression in regenerated bone compared to control, SDF‐1 or EX‐4 in vivo.

Conclusions

SDF‐1/EX‐4 cotherapy synergistically regulated PDLSC activities, promoted periodontal bone formation, thereby providing a new strategy for periodontal bone regeneration.

Effect of periodontal treatment on the glomerular filtration rate, reduction of inflammatory markers and mortality in patients with chronic kidney disease: A systematic review

Aim

To assess the effect of periodontal treatment (PT) on glomerular filtration rate (GFR), systemic inflammation, or mortality in patients with chronic kidney disease (CKD).

Methods

A literature search was performed on PubMed and Web of Science databases on articles published until December 2019. The PRISMA guidelines were used throughout the manuscript.

Results

Of the total studies found, only 18 met the inclusion criteria; four retrospective and 14 prospective studies (including 3 randomized controlled trials–RCT). After PT, 3 studies investigated GFR, 2 found significant improvement; 11 (including 2 RCTs) investigated C-reactive protein levels, 9 found a significant improvement (including the 2 RCTs); 5 (including 3 RCTs) investigated Interleukine-6 level, 4 found a significant improvement (including 2 RCTs) and 2 studies evaluated mortality, one (retrospective study) found a significant difference.

Conclusions

Within the limitations of the present study, PT seems to improve CKD status, especially by reducing the systemic inflammation. Further RCTs are needed to confirm the results and specifically assess the influence of different types of PT in CKD patients. Taking into consideration the ability of PT to prevent further tooth loss and denutrition, early management of periodontitis is extremely important in patients with impaired renal function.

Individual predisposition and the intricate interplay between systemic biomarkers and periodontal risk in a general population

BACKGROUND

Increasing age is associated with systemic diseases as well as with periodontal diseases. We wondered whether a biological age score constructed exclusively from systemic biomarkers would reflect periodontal risk factors at baseline and tooth loss as well as periodontal outcome during 10 years follow-up.

METHODS

From the Study of Health in Pomerania (SHIP) 2256 participants (1072 male, 1184 female) were studied for the relationship of the systemic biomarkers glycated hemoglobin (HbA1c), low density lipoprotein cholesterol (LDL), fibrinogen, white blood cell count, blood pressure, and waist circumference to their age. Construction of a biological age (BA) score allowed its comparison with the participants' actual chronological age (CA) and their predisposition to periodontal disease.

RESULTS

Though nearly identical in CA, participants appearing younger than their true age had a significantly reduced burden of periodontal risk factors. If BA > CA, then risk factors were more frequent including smoking, oral hygiene, dental visits, education, and income. After 10 years, in participants with identical CA, tooth loss followed their BA calculated at baseline, that is, with BA > CA fewer teeth were preserved. Similarly, periodontal measures varied according to BA; sex differences were obvious. Most significant were BA-related differences in inflammatory and anthropometry parameters.

CONCLUSIONS

The results support the assumption that risk profiles aggregated in BA constitute a characteristic susceptibility pattern unique to each individual, common to both systemic and periodontal diseases. Although BA was constructed exclusively from systemic measures at baseline, BA reflects the oral conditions at follow-up.

Does Last Year's Cost Predict the Present Cost? An Application of Machine Leaning for the Japanese Area-Basis Public Health Insurance Database

The increasing healthcare cost imposes a large economic burden for the Japanese government. Predicting the healthcare cost may be a useful tool for policy making. A database of the area-basis public health insurance of one city was analyzed to predict the medical healthcare cost by the dental healthcare cost with a machine learning strategy. The 30,340 subjects who had continued registration of the area-basis public health insurance of Ebina city during April 2017 to September 2018 were analyzed. The sum of the healthcare cost was JPY 13,548,831,930. The per capita healthcare cost was JPY 446,567. The proportion of medical healthcare cost, medication cost, and dental healthcare cost was 78%, 15%, and 7%, respectively. By the results of the neural network model, the medical healthcare cost proportionally depended on the medical healthcare cost of the previous year. The dental healthcare cost of the previous year had a reducing effect on the medical healthcare cost. However, the effect was very small. Oral health may be a risk for chronic diseases. However, when evaluated by the healthcare cost, its effect was very small during the observation period.

Is There Any Association Between Chronic Periodontitis and Anxiety in Adults? A Systematic Review

Periodontitis is a multifactorial disease triggered by dysbiotic biofilms, involving the host's immune response, systemic and behavioral factors, including psychosocial conditions. This systematic review aimed to investigate the possible association between periodontitis and anxiety in adults. Searches were performed in PubMed, Scopus, Web of Science, Lilacs, Cochrane, and OpenGrey databases, without language restrictions, considering studies in adults (P-Participants), with (E-Exposure) and without periodontitis (C- Comparison) in an outcome of association with anxiety (O-outcome). Methodological quality assessment was carried out using the Newcastle-Ottawa protocol for case-control and cross-sectional studies, followed by an analysis of the level of evidence using the GRADE tool. Metanalysis was not performed due to several differences in methods applied by authors in primary studies. Eleven observational studies were selected according to the inclusion criteria from the total of 6,380 studies retrieved from databases. Eight studies demonstrated higher anxiety levels in subjects with periodontitis, among which only one study presented a high risk of bias. The GRADE tool revealed a low level of evidence for the anxiety outcome measured by the State-Trait Anxiety Inventory (STAI), both for case-control and cross-sectional studies. However, since anxiety may affect the quality of life of many subjects, it reinforces the need for further studies that evaluate this association for more extended periods. Clinical Trial Registration:PROSPERO-CRD42020190445.

Cytokines and Their Genetic Polymorphisms Related to Periodontal Disease

Periodontal disease (PD) is a chronic inflammatory disease caused by the accumulation of bacterial plaque biofilm on the teeth and the host immune responses. PD pathogenesis is complex and includes genetic, environmental, and autoimmune factors. Numerous studies have suggested that the connection of genetic and environmental factors induces the disease process leading to a response by both T cells and B cells and the increased synthesis of pro-inflammatory mediators such as cytokines. Many studies have shown that pro-inflammatory cytokines play a significant role in the pathogenesis of PD. The studies have also indicated that single nucleotide polymorphisms (SNPs) in cytokine genes may be associated with risk and severity of PD. In this narrative review, we discuss the role of selected cytokines and their gene polymorphisms in the pathogenesis of periodontal disease.

Autophagy-mediated regulation patterns contribute to the alterations of the immune microenvironment in periodontitis

The relationship between autophagy and immunity has been thoroughly investigated. However, little is known about the role of autophagy in shaping the immune-microenvironment of periodontitis. Thus, we aim to explore the impact of autophagy on the immune-microenvironment of periodontitis. The expression distinctions of autophagy genes between healthy and periodontitis samples have been investigated. The connections between autophagy and immune characteristics including infiltrating immunocyte, immune reaction and human leukocyte antigen (HLA) gene were evaluated. The distinct autophagy-mediated expression patterns were identified and immune characteristics under distinct patterns were revealed. Autophagy phenotype-related genes were identified. 16 autophagy genes were dysregulated and a ten-autophagy classifier was constructed that can well distinguish periodontitis and healthy samples. Immune characteristics were closely related to autophagy: higher expression of EDEM1 positively relates to infiltrating activated B cell; NCKAP1 negatively relates to monocyte; CXCR4 enhances BCR Signaling Pathway and PEX3 decreases the activity of TNF Family Members Receptors; positive expression correlation of EDEM1-HLADOB and negative correlation of RAB11A-HLADOB were observed. Two distinct autophagy expression patterns were identified which demonstrated different immune characteristics. 4309 autophagy phenotype-related genes were identified, and 219 of them were related to immunity, whose biological functions were found to be involved in immunocyte regulations. Our study revealed the strong impact of autophagy on the immune-microenvironment of periodontitis and brought new insights into the understanding of the pathogenesis of periodontitis.

Relationship between Periodontitis and Glaucoma: A Cross-Sectional Study

The objective of this cross-sectional study was to evaluate the association between periodontitis and glaucoma. This prospective cohort study used epidemiological data from the Korean Genome and Epidemiology Study performed between 2004 and 2016. Among 173,209 participants, 9572 patients with periodontitis and 115,332 controls (nonperiodontitis) were selected. We analysed the history of glaucoma in periodontitis and control participants. The participants were interviewed regarding their history of hypertension, diabetes mellitus, hyperlipidaemia, periodontitis, glaucoma, smoking, and alcohol consumption by trained interviewers. A logistic regression model was created to analyse the odds ratio of having a history of glaucoma among patients with periodontitis. Two-tailed analyses using chi-square and independent t-tests were used for statistical analysis. The adjusted odds ratio of periodontitis as a risk factor for glaucoma was 3.44 (95% confidence interval = 2.99–3.97, $p<0.001$ ). This study demonstrated that glaucoma was associated with periodontitis.

Assessment of mucin and alpha-amylase levels in gingival crevicular fluid of chronic periodontitis patients

BACKGROUND

Chronic periodontitis is the most common form of periodontitis. Several immune and inflammatory factors responsible for periodontal destruction have been found in gingival crevicular fluid (GCF). The current study was conducted to determine the correlation between mucin and alpha-amylase protein values in GCF with chronic periodontitis.

METHOD

Forty-five patients with moderate-to-severe chronic periodontitis were selected. Samples of GCF were taken from a specific part of a single root tooth and placed in a closed test tube containing phosphate-buffered saline (PBS) (pH = 7). Sampling was done again after one month. Pre- and post-treatment samples were analyzed for measuring the levels of mucin and alpha-amylase proteins.

RESULTS

Paired t test results for these two variables showed that the difference between mucin and alpha-amylase levels before and after treatment is significant.

CONCLUSION

The level of both mucin and alpha-amylase in GCF in patients with chronic periodontitis was higher than that of patients who have recovered successfully; and evaluating the values of these two markers could be used to determine the activity of the periodontal disease.

Role of IL-6 and STAT3 signaling in dihydropyridine-induced gingival overgrowth fibroblasts

OBJECTIVES

This study analyzed the role of the interleukin (IL)-6/signal transducer and activator of transcription 3 (STAT3) pathway in dihydropyridine-induced gingival overgrowth (DIGO) fibroblasts.

MATERIALS AND METHODS

Tissue samples were obtained through surgical dissection from five DIGO patients and five healthy individuals. Cell cultures were conditioned with nifedipine (Nif) (0.34 µM) and stimulated with IL-1β (10 ng/ml) to clarify whether IL-6 upregulates extracellular matrix overproduction or has an impact on the cell proliferation rate of DIGO fibroblasts. STAT3 was knocked down using short hairpin (sh)RNA to determine its role in collagen (Col) type I alpha 1 (Colα1(I)) synthesis.

RESULTS

Results showed that phosphorylated (p)STAT3 nuclear translocation was activated by a simulated autocrine concentration (50 ng/ml) of IL-6, and application of an anti-IL-6 antibody significantly decreased the pSTAT3/STAT3 ratio in DIGO fibroblasts. STAT3 knockdown significantly decreased STAT3 and Colα1(I) expressions in DIGO cells. DIGO tissues presented stronger proliferating cell nuclear antigen (PCNA) expression than did healthy individuals under the effect of IL-1β/Nif treatment.

CONCLUSIONS

Gingival inflammation (e.g., IL-1β) and taking dihydropyridine (e.g., Nif) may additively stimulate Col overproduction through the IL-6-STAT3-Colα1(I) cascade in DIGO cells. IL-6-STAT3 signaling may be considered a target for the control of DIGO.

Chronic Periodontitis is Associated With Cerebral Atherosclerosis -A Nationwide Study

Introduction Chronic periodontitis and atherosclerosis share common risk factors and produce the same inflammatory markers. Many studies found a high prevalence of chronic periodontitis in patients with atherosclerosis but there is no strong evidence to support a specific association of chronic periodontitis with cerebral atherosclerosis. We aimed to study the concurrent prevalence and association of chronic periodontitis with cerebral atherosclerosis and cerebrovascular diseases among the US population. Methods We performed a cross-sectional analysis of a Nationwide Inpatient Sample with adult hospitalizations to identify the primary diagnosis of cerebrovascular diseases [acute ischemic stroke (AIS), hemorrhagic stroke (HS), and transient ischemic attack (TIA)] with concurrent cerebral atherosclerosis and chronic periodontitis. Multivariate survey logistic regression models were fitted to evaluate the linkage of chronic periodontitis with cerebral atherosclerosis and cerebrovascular diseases. Results Of total 56,499,788 hospitalizations, 0.01% had chronic periodontitis. Prevalence of chronic periodontitis was higher in 50-64 years (36.18% vs. 23.91%), males (59.19% vs. 41.06% in females), Afro-Americans (25.93% vs. 15.21%), and 0-25th percentile median-household-income-category (38.31% vs. 30.15%) compared to non-chronic periodontitis. There was significantly higher prevalence of cerebral atherosclerosis (0.71% vs. 0.41%; p<0.0001) with weak evidence of high prevalence of cerebrovascular diseases (AIS:2.21% vs. 1.97%; p=0.1563; HS:0.57% vs. 0.46%; p=0.1560) among chronic periodontitis compared to non-chronic periodontitis. In regression analysis, odds of having cerebral atherosclerosis were 2.48-folds higher in patients with chronic periodontitis compared to that without-chronic periodontitis, and cerebral atherosclerosis patients were associated with higher odds of TIA (aOR:2.40; p<0.0001), AIS (aOR:3.35; p<0.0001), and HS (aOR:1.51; p<0.0001) compared to without-cerebral atherosclerosis. No significant relationship between chronic periodontitis and cerebrovascular diseases was observed. Conclusion Although chronic periodontitis may not directly increase the risk of cerebrovascular diseases, it increases the burden of cerebrovascular diseases by evidently increasing the risk of cerebral atherosclerosis. Early identification of chronic periodontitis and atherosclerotic risk factors may help to mitigate the risk of cerebrovascular diseases.

Role of YAP1 gene in proliferation, osteogenic differentiation, and apoptosis of human periodontal ligament stem cells induced by TNF-α

BACKGROUND

Periodontitis is a chronic inflammatory disease that occurs in periodontal tissues and can cause tooth loosening and loss in severe cases. As the main effector of downstream of Hippo signaling pathway, yes-related protein 1 (YAP1) plays an important role in cell proliferation and differentiation. However, the role of YAP1 in periodontitis has not been reported.

METHODS

Cell activity was detected by Cell Counting Kit-8 (CCK-8). YAP1 was overexpressed by cell transfection, and then RT-qPCR and western blot were used to detect the expression of YAP1. The cell proliferation was determined by clone formation assay, and the expression of proliferation-related proteins was determined by western blot. The cell differentiation was detected by ELISA kit of alkaline phosphatase activity (ALP) and alizarin red staining. Finally, western blot was used to detect the expression of differentiation-related protein and Hippo signaling pathway-related proteins. Apoptosis was detected by flow cytometry.

RESULTS

With the increase of concentration induced by TNF-α, the cell survival rate of human periodontal ligament stem cells (HPDLSCs) decreased significantly. After the overexpression of YAP1, cell proliferation and proliferation-related protein expression increased. Overexpression of YAP1 can improve the differentiation and the formation of osteoblasts of HPDLSCs induced by TNF-α. The expression of Hippo signaling pathway-related proteins transcriptional coactivators with PDZ binding domains (TAZ), TEA domain family member (TRED) increased and proliferation-related protein P27 decreased, whereas there was no significant change in the expression of MST1.

CONCLUSION

TNF-α can inhibit proliferation and osteogenic differentiation of HPDLSCs, which can be ameliorated by the YAP1 gene through the Hippo signaling pathway. Our paper suggested that YAP1 may be a potential therapeutic target for periodontitis.

Neuroinflammation changes with periodontal inflammation status during periodontitis in wild-type mice

OBJECTIVE

To investigate neuroinflammation under different periodontal status.

MATERIALS AND METHODS

Experimental periodontitis was induced by molar ligation (Lig group) or periodontal injection of lipopolysaccharide (LPS, Lps group). Periodontal status was assessed by alveolar bone resorption and periodontal inflammation. Micro-computed tomography and haematoxylin-eosin staining were performed to assess alveolar bone resorption and periodontal inflammation, respectively. Neuroinflammation was assessed by glial cell proliferation and proinflammatory factor expression. Microgliosis was determined by immunofluorescence. Astrogliosis was determined by immunohistochemistry. Expressions of tumour necrosis factor-alpha (TNF-α) and interleukin (IL)-1β were assessed by enzyme-linked immunosorbent assay.

RESULTS

Microgliosis and astrogliosis in the Lig group were notable with molar ligation for 2 weeks and 4 weeks (p < .05), but were only slightly different similar from the control group by week 12. Microgliosis and astrogliosis in the Lps group were significant with LPS injection for 4 and 8 weeks (p < .05). The groups displayed a positive correlation between the degree of periodontal inflammation and the number of glial cells (p < .05). Expressions of IL-1β and TNF-α in the Lps group were significantly increased with LPS injection for 8 weeks (p < .05). In the Lig group, only TNF-α was highly expressed with molar ligation for 12 weeks (p < .05).

CONCLUSION

Both models demonstrated that the inflammatory response in the hippocampus of mice can change during periodontitis depending on the periodontal inflammation status.

The role of PHF8 and TLR4 in osteogenic differentiation of periodontal ligament cells in inflammatory environment

BACKGROUND

Histone methylation is considered to play an important role in the occurrence and development of periodontitis. Plant homeodomain finger protein 8 (PHF8), a histone demethylase, has been shown to regulate inflammation and osteogenic differentiation of bone marrow stromal cells (BMSCs). This study aimed to detect the functions of PHF8 and TLR4 in osteogenic differentiation in an inflammatory environment induced by Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) METHODS: A periodontitis mouse model was established, and the mice were treated with TAK-242. Immunohistochemical staining was used to detect the expression of PHF8 in periodontal tissue. Periodontal ligament cells (PDLCs) were treated with mineralization induction medium supplemented with Pg-LPS and/or TAK-242, and a Cell Counting Kit-8 (CCK-8) assay was used to detect the proliferation of PDLCs. Real-time PCR and western blotting were used to detect the mRNA and protein expression levels, respectively, of PHF8, toll-like receptor 4 (TLR4) and the other osteogenic markers alkaline phosphatase (ALP), osteocalcin (OCN), Special AT-rich sequence-binding protein 2 (Satb2) and Runt-related transcription factor 2 (Runx2) RESULTS: Periodontitis reduced PHF8 expression in periodontal tissue, and TAK-242 partially reversed this downregulation. An in vitro experiment revealed that the mRNA and protein expression levels of PHF8 were significantly upregulated during the osteogenic differentiation of PDLCs. Alizarin red staining showed that the mineralized nodules of PDLCs in osteogenic induction group were more than those in control group. Real-time PCR and western blot results indicated that Pg-LPS inhibited PHF8 expression and upregulated TLR4 expression in PDLCs. TAK-242 inhibited TLR4 and partially reversed the inhibition of PHF8 expression and osteogenic differentiation induced by Pg-LPS in PDLCs CONCLUSION: PHF8 and TLR4 play important roles in periodontitis. Pg-LPS inhibits the expression of PHF8 via upregulation of TLR4 and might further inhibit the osteogenic differentiation of PDLCs. However, the specific mechanisms involved remain to be explored.

Is periodontal disease a risk factor for severe COVID-19 illness?

Periodontal disease (PD) comprises a group of diseases involving inflammatory aspects of the host and dysbiotic events that affect periodontal tissues and could have systemic implications. Diverse factors and comorbidities have been closely associated with PD such as diabetes, obesity, aging, hypertension, and so on; although, underlying mechanisms or causal associations have not been established completely. Interestingly, these same factors have been widely associated with progression or severe coronavirus disease 2019 (COVID-19), an illness caused by coronavirus SARS-CoV-2. Since inflammatory and dysbiotic factors as well as comorbidities affect systemic health, it is possible that periodontal status indicates the risk of complication of COVID-19. However, assessment of oral health history including periodontal status in COVID-19 patients has not been reported. Knowing PD is associated with severe COVID-19 could help identify risk groups and establish pertinent recommendations.

Effect of per Capita Income on the Relationship between Periodontal Disease during Pregnancy and the Risk of Preterm Birth and Low Birth Weight Newborn. Systematic Review and Meta-Analysis

This work analyzed the available evidence in the scientific literature about the risk of preterm birth and/or giving birth to low birth weight newborns in pregnant women with periodontal disease. A systematic search was carried out in three databases for observational cohort studies that related periodontal disease in pregnant women with the risk of preterm delivery and/or low birth weight, and that gave their results in relative risk (RR) values. Eleven articles were found, meeting the inclusion criteria. Statistically significant values were obtained regarding the risk of preterm birth in pregnant women with periodontitis (RR = 1.67 (1.17-2.38), 95% confidence interval (CI)), and low birth weight (RR = 2.53 (1.61-3.98) 95% CI). When a meta-regression was carried out to relate these results to the income level of each country, statistically significant results were also obtained; on the one hand, for preterm birth, a RR = 1.8 (1.43-2.27) 95% CI was obtained and, on the other hand, for low birth weight, RR = 2.9 (1.98-4.26) 95% CI. A statistically significant association of periodontitis, and the two childbirth complications studied was found, when studying the association between these results and the country's per capita income level. However, more studies and clinical trials are needed in this regard to confirm the conclusions obtained.

Therapeutic effects of antibiotics loaded cellulose nanofiber and κ-carrageenan oligosaccharide composite hydrogels for periodontitis treatment

Periodontitis is an inflammatory disease that can lead to the periodontal pocket formation and tooth loss. This study was aimed to develop antimicrobials loaded hydrogels composed of cellulose nanofibers (CNF) and κ-carrageenan oligosaccharides (CO) nanoparticles for the treatment of periodontitis. Two antimicrobial agents such as surfactin and Herbmedotcin were selected as the therapeutic agents and the hydrogels were formulated based on the increasing concentration of surfactin. The proposed material has high thermal stability, controlled release, and water absorption capacity. This study was proceeded by investigating the in vitro antibacterial and anti-inflammatory properties of the hydrogels. This material has strong antibacterial activity against periodontal pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Fusobacterium nucleatum, and Pseudomonas aeruginosa. Moreover, a significant increase in malondialdehyde (MDA) production and a decrease in biofilm formation and metabolic activity of the bacteria was observed in the presence of hydrogel. Besides, it reduced the reactive oxygen species (ROS) generation, transcription factor, and cytokines production in human gingival fibroblast cells (HGF) under inflammatory conditions. In conclusion, the hydrogels were successfully developed and proven to have antibacterial and anti-inflammatory properties for the treatment of periodontitis. Thus, it can be used as an excellent candidate for periodontitis treatment.

Evaluation of serum and gingival crevicular fluid microRNA-223, microRNA-203 and microRNA-200b expression in chronic periodontitis patients with and without diabetes type 2

microRNA dysregulation is a reported feature of multiple pathologies, including periodontal disease, as demonstrated on cell lines, in animal models, and tissues biopsies, but serum and gingival crevicular fluid microRNA expression data in humans is scarce, especially with the diabetes (type 2) systemic complication.

OBJECTIVE

To assess serum and gingival crevicular fluid relative quantification levels of miR-223, miR-203, and miR-200b in chronic periodontitis and type 2 diabetic chronic periodontitis patients to address their possible implication in chronic periodontitis pathogenesis and its systemic complications and also to correlate their differential expression with some inflammatory (serum tumor necrosis factor-α and interleukin-10) parameters.

METHODS

Sixty subjects were recruited and divided into three groups; chronic periodontitis (n = 20), type 2 diabetic chronic periodontitis (n = 20), and healthy control (n = 20). Both serum and gingival crevicular fluid were collected from each participant for miRNA expression analysis and serum inflammatory parameters assessment.

RESULTS

A significant increase in the relative quantification levels of miR-223 and miR-200b were detected in patient groups along with a positive correlation with tumor necrosis factor-α. However, miR-203 was significantly decreased in patient groups associated with a negative correlation with tumor necrosis factor-α.

CONCLUSIONS

miR-223 and miR-200b have a potential role in chronic periodontitis pathogenesis associated with type 2 diabetes, with the ability to induce tumor necrosis factor-α secretion, while miR-203 might have a protective and healing role due to the negative correlation with the serum tumor necrosis factor-α levels found. Therefore, they may be considered as a promising therapeutic target and effective serum disease biomarkers.

Periodontitis and the subsequent risk of glaucoma: results from the real-world practice

Periodontitis is a multifactorial inflammatory disease that can cause tooth loss and contribute to systemic inflammation. It is suggested that periodontitis may be associated with the development of glaucoma. Based on data from Taiwan’s National Health Insurance Research Database, a retrospective cohort study was conducted to investigate the risk of developing glaucoma in patients with periodontitis. The periodontitis cohort consisted of newly diagnosed adult patients (n = 194,090, minimum age = 20 years) between 2000 and 2012. The comparison group included age-, gender-, and diagnosis date-matched people without periodontitis (n = 194,090, minimum age = 20 years). Incident glaucoma was monitored until the end of 2013. Hazard ratios (HRs) with confidence intervals (CIs) were established based on the Cox proportional hazard models. The risk of developing glaucoma was higher in patients with periodontitis than those without periodontitis (31.2 vs. 23.3 patients per 10,000 person-years, with an adjusted HR of 1.26 [95% CI 1.21–1.32]). A high risk was evident even after stratifying by age (adjusted HRs = 1.34 [1.26–1.44] for ages 20–49, 1.24 [1.13–1.36] for ages ≥ 65, and 1.20 [1.12–1.29] for ages 50–64 years), sex (adjusted HRs = 1.33 [1.24–1.41] and 1.21 [1.14–1.28] for men and women, respectively), presence of comorbidity (adjusted HRs = 1.38 [1.29–1.47] and 1.18 [1.12–1.25] for without and with comorbidity, respectively), and corticosteroid use (adjusted HRs = 1.27 [1.21–1.33] and 1.21 [1.08–1.35] for without and with corticosteroid use, respectively). Specifically, patients with periodontitis exhibited a significantly high risk of primary open-angle glaucoma (adjusted HR = 1.31 [1.21–1.32]) but not for primary closed-angle glaucoma (adjusted HR = 1.05 [0.94–1.17]). People with periodontitis are at a greater risk of glaucoma than individuals without periodontitis. Ocular health should be emphasized for such patients, and the underlying mechanisms need further investigation.

Investigation of the Effect of Formaldehyde on the Condition of Periodontal Tissues of Woodworking Industry Workers

The high prevalence of periodontal diseases in workers with professional contact with unfavorable factors of the production environment is an unresolved problem of dentistry. This study aimed to investigate the harmful effects of formaldehyde on periodontal tissues in woodworkers who have long-term contact with formaldehyde in their professional activities. Sixty-nine men with occupational exposure to formaldehyde were examined to study the effect of formaldehyde on the human periodontal tissues, looking particularly at signs of the periodontal tissues’ inflammatory process using a series of periodontal indices. The study results showed that the condition of periodontal tissues was statistically significantly worse in woodworkers who have long-term contact with formaldehyde in their professional activities. However, the hygiene status was not significantly different in the main group and the comparison group. Thus, we concluded that working under conditions of constant exposure to formaldehyde has a negative effect on the condition of periodontal tissues.

Increased levels of interleukin-32 isoforms alpha, beta, gamma, and delta in the gingival crevicular fluid and plasma of the patients with periodontitis

BACKGROUND AND OBJECTIVE

Interleukin (IL)-32, which has been recently reported to be associated with periodontitis, has been suggested to have pleiotropic effect due to its 9 different isoforms. The aim of this study was to investigate the levels of IL-32α, IL-32β, IL-32γ, IL-32δ isoforms in gingival crevicular fluid (GCF) and plasma before and after non-surgical periodontal treatment in patients with periodontitis (P).

MATERIALS AND METHODS

Twenty-seven P and 27 periodontally healthy controls (C) were recruited in this study. Non-surgical periodontal treatment was performed to periodontitis patients. GCF and plasma sampling and clinical periodontal parameters were evaluated before and 1 month after treatment. Enzyme-linked immunosorbent assay was used to analyze the levels of IL-32α, IL-32β, IL-32γ, IL-32δ isoforms in GCF and plasma samples.

RESULTS

The levels of IL-32α, IL-32β, IL-32γ, and IL-32δ in plasma and GCF were significantly higher in patients with periodontitis than healthy controls (P < .001). In P group, plasma and GCF IL-32α, IL-32β, IL-32γ, and IL-32δ levels after non-surgical periodontal treatment were lower when compared to baseline (P < .001). Moreover, there was a positive correlation between GCF and plasma IL-32α, IL-32β, IL-32γ, and IL-32δ levels in all groups at baseline and after treatment (P < .05).

CONCLUSION

The study supported that there was a relationship between elevated levels of IL-32 isoforms and periodontitis. Also, our novel findings suggest that the pro-inflammatory role of IL-32 in the periodontitis may be originated from IL-32α, IL-32β, IL-32γ, and IL-32δ isoforms.

Multimorbidity and oral health: need for new models of care

Multimorbidity is defined as patients living with two or more chronic health conditions. The prevalence of multimorbidity is increasing, driven by the ageing population, and represents a major challenge to all healthcare systems because these patients are heavy users of services. The link with oral health is growing although there is need for further robust evidence. There is also need for new models of care to address oral health in patients with multimorbidity.

The Porphyromonas gingivalis inhibitory effects, antioxidant effects and the safety of a Sri Lankan traditional betel quid - an in vitro study

Background

The Sri Lankan traditional betel quid (TBQ) which had been extensively used in the country before its colonization is claimed to have antiperiodontopathic effects in the Sri Lankan folklore. However, there is no reported scientific evidence to support the claimed antiperiodontopathic effects mediated by this TBQ. The present study was carried out to investigate the protective effect of the Sri Lankan TBQ in the pathogenesis of periodontitis.

Methods

We investigate the ethyl acetate extract of the Sri Lankan TBQ for its antibacterial effects against the keystone periodontopathic bacterium, P. gingivalis and also its antioxidant potential, which is important to protect the periodontium from oxidative stress. Further, its safety was analyzed using the cytokinesis block micronucleus assay on human peripheral blood lymphocytes (PBLs).

Results

Ethyl acetate extract of this TBQ inhibited the growth of P. gingivalis with a minimum bactericidal concentration (MBC) of 125 μg/ml. It was found to be a rich source of polyphenols and displayed considerable DPPH and ABTS radical scavenging activities and a strong ferric reducing antioxidant power. This extract could protect the cultured human gingival fibroblasts from H₂O₂ induced oxidative stress. In addition, this TBQ extract was not genotoxic to human PBLs even at a concentration of 2.5 mg/ml. Moreover, it exhibited protective effects against bleomycin induced genotoxicity in PBLs.

Conclusion

Ethyl acetate extract of the Sri Lankan TBQ is a source of natural antibacterial compounds against P. gingivalis. It is also a source of natural antioxidants which can protect human gingival fibroblasts from H₂O₂ induced oxidative stress. These properties of the TBQ may have contributed to its claimed antiperiodontopathic effects. Besides, it was found to be relatively non-toxic to human cells. Thus this TBQ extract has a huge potential to be developed as a novel adjunctive therapeutic lead against periodontitis.

LOX-1 Regulates P. gingivalis-Induced Monocyte Migration and Adhesion to Human Umbilical Vein Endothelial Cells

Porphyromonas gingivalis (P. gingivalis) is one of the main periodontal bacteria. This pathogen was reported to enhance monocyte migration and adhesion to endothelial cells in atherosclerosis. The scavenger receptor lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) plays a pivotal role in atherogenesis. The aim of this study was to investigate whether LOX-1 modulates P. gingivalis-mediated monocyte migration and adhesion to endothelial cells and how it works. The results showed that the migration and adhesion of monocytic THP-1 cells to human umbilical vein endothelial cells (HUVECs) were significantly enhanced when HUVECs or THP-1 cells were challenged with P. gingivalis. Meanwhile, the expression level of LOX-1 in both HUVECs and THP-1 cells were also significantly increased by P. gingivalis stimulation. It is well known that ligand/receptor pairs monocyte chemoattractant protein-1 (MCP-1)/CC chemokine receptor 2 (CCR2), selectins/Integrins, and cell adhesion molecules (CAMs)/Integrins mediate monocyte migration and adhesion to endothelial cells. In this study, LOX-1 was demonstrated to be crucially involved in P. gingivalis-induced THP-1 cell migration and adhesion to HUVECs, by regulating expression of ligands MCP-1, intercellular adhesion molecule-1 (ICAM-1) and E-selectin in HUVECs and that of their receptors CCR2 and Integrin αMβ2 in THP-1 cells. The nuclear factor-kappa B (NF-κB) signaling pathway was proved to be involved in this process. In conclusion, LOX-1 plays a crucial role in P. gingivalis-induced monocyte migration and adhesion to endothelial cells. This result implies LOX-1 may act as a bridge in linking periodontitis to atherosclerosis.

Association between periodontitis and bipolar disorder: A nationwide cohort study

Whether periodontitis is a risk factor for developing bipolar disorders (BD) has not been investigated. We aimed to determine whether periodontitis is associated with the subsequent development of BD and examine the risk factors for BD among patients with periodontitis.Using ambulatory and inpatient claims data from the National Health Insurance Research Database (NHIRD), we identified 12,337 patients who were aged at least 20 years and newly diagnosed with periodontitis between 2000 and 2004. The date of the first claim with a periodontitis diagnosis was set as the index date. For each patient with periodontitis, 4 subjects without a history of periodontitis were randomly selected from the NHIRD and frequency-matched with the patients with periodontitis according to sex, age (in 5-year bands), and index year.The periodontitis group had a mean age of 44.0 ± 13.7 years and slight predominance of men (51.3%). Compared with the subjects without periodontitis, the patients with periodontitis had higher prevalence of diabetes mellitus, hyperlipidemia, hypertension, ischemic heart disease, stroke, head injury, major depressive disorder, chronic obstructive pulmonary disease (COPD), and asthma (P < .001). The incidence rate of BD was higher in the periodontitis group than in the non-periodontitis group (2.74 vs 1.46 per 1000 person-year), with an adjusted hazard ratio of 1.82 (95% confidence interval = 1.59-2.08) after adjustment for sex, age, and comorbidities.The patients with periodontitis exhibited a significantly higher risk of developing BD. Keep the better oral hygiene to reduce periodontitis might be a preventive strategy for BD.

Comparisons of Periodontal Status between Females Referenced for Fertility Treatment and Fertile Counterparts: A Pilot Case-Control Study

Studies investigating the periodontal status of women seeking fertility treatment have never been conducted. The purpose of this pilot study was to compare the periodontal status among females referenced to a Fertility Clinic (FC) when compared to matched females from a representative regional epidemiological sample. Our secondary aims were to investigate if periodontal clinical measures differ between these two groups of females and how they impact on oral health-related quality of life (OHRQoL). We enrolled 18 women from an FC and 18 age, race and body mass index matched controls from the epidemiological survey Study of Periodontal Health in Almada-Seixal (SoPHiAS). In each subject, we performed a circumferential periodontal inspection to infer the periodontal status and applied a questionnaire measuring OHRQoL. FC females presented higher levels of periodontal disease, with higher periodontal epithelial surface area, periodontal probing depth and clinical attachment loss. However, periodontal diseases did not impact OHRQoL in this particular group of women seeking fertility care, suggesting unawareness about periodontal diseases. Within the limitations of this study, females referenced for fertility treatment presented worse periodontal measures than females from a representative control sample. These preliminary results may support future prospective studies to further explore the periodontal status and possible consequences in women seeking fertility care.

Role of the oral microbiota in cancer evolution and progression

Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial roles in the health status of individuals. Epidemiological studies related to molecular pathology have revealed that there is a close relationship between oral microbiota and tumor occurrence. Oral microbiota has attracted considerable attention for its role in in‐situ or distant tumor progression. Anaerobic oral bacteria with potential pathogenic abilities, especially Fusobacterium nucleatum and Porphyromonas gingivalis, are well studied and have close relationships with various types of carcinomas. Some aerobic bacteria such as Parvimonas are also linked to tumorigenesis. Moreover, human papillomavirus, oral fungi, and parasites are closely associated with oropharyngeal carcinoma. Microbial dysbiosis, colonization, and translocation of oral microbiota are necessary for implementation of carcinogenic functions. Various underlying mechanisms of oral microbiota‐induced carcinogenesis have been reported including excessive inflammatory reaction, immunosuppression of host, promotion of malignant transformation, antiapoptotic activity, and secretion of carcinogens. In this review, we have systemically described the impact of oral microbial abnormalities on carcinogenesis and the future directions in this field for bringing in new ideas for effective prevention of tumors.

The association of periodontal disease with the complications of diabetes mellitus. A systematic review

This review investigated the association of periodontal disease with diabetes mellitus (DM) and diabetic complications. PubMed/MEDLINE was searched including search terms "periodontal" OR "periodontitis" AND "diabetic complications" OR "diabetic retinopathy" OR "diabetic nephropathy" OR "diabetic neuropathy" OR "cardiovascular disease diabetes" OR "myocardial infarction diabetes" OR "cerebrovascular disease diabetes" OR "stroke diabetes" OR "peripheral vascular disease diabetes". Fourteen studies included in this review consistently reported an increased risk for diabetic complications including microvascular, macrovascular and death in the presence of periodontal disease. Higher risks for diabetic retinopathy (odds ratios: 2.8-8.7), neuropathy (3.2-6.6), nephropathy (1.9-8.5), cardiovascular complications (1.28-17.7) and mortality (2.3-8.5) were reported for people with diabetes with periodontitis compared to those with diabetes who have no periodontitis. This novel review summarizes current data providing further evidence of a link between poor oral health and DM and its complications. It has also drawn attention to major limitations of the available data linking periodontal disease and diabetic complications.

A semi-synthetic flavonoid from Bauhinia pulchella stem attenuates inflammatory osteolysis in periodontitis in rats: Impact on cytokine levels, oxidative stress, and RANK/RANKL/OPG pathway

OBJECTIVES

Many species of theBauhinia genus have been widely used in folk medicine as analgesic, anti-inflammatory and antioxidant agents. (-)-Fisetinidol palmitate is a semi-syntetic flavonoid obtained from the ethanolic extract of the stem of Bauhinia pulchella. This study aimed to evaluate the antiresorptive effect of the semi-syntetic (-)-fisetinidol palmitate in ligature-induced periodontitis in rats. Also, it evaluated the mechanism of action of (-)-fisetinidol palmitate and its toxicity.

DESIGN

Periodontitis was inducedvia a nylon thread ligature (3.0) around the second upper left molars. Rats were treated (oral gavage) once a day for 11 days with (-)-fisetinidol palmitate (0.01 or 0.1 mg/kg) or saline vehicle.

RESULTS

(-)-Fisetinidol palmitate (0.1 mg/kg) reduced alveolar bone loss, increased bone alkaline phosphatase (BALP), superoxide dismutase (SOD), and catalase (CAT) activity; also, it decreased IL1-β, IL-8/CINC-1, nitrite/nitrate levels and myeloperoxidase activity. (-)-Fisetinidol palmitate reduced the mRNA levels of IL1-β, IL-6, RANK, and RANK-L, while it increased the OPG ones. No statistical differences (P > 0.05) were observed in the transaminases (ALT, AST) and Total Alkaline Phosphatase (TALP) levels among groups.

(-)- CONCLUSIONS

Fisetinidol palmitate did not result in any signs of toxicity and had anti-resorptive effects in a pre-clinical trial of periodontitis, showing antioxidant activity with the involvement of the RANK/RANKL/OPG pathway.

Interleukin-1α and -1β assessment in the gingival crevicular fluid of periodontal patients with chronic hepatitis C

The study assessed whether the increased production of interleukin-1α (IL-1α) and interleukin-1β (IL-1β), as a result of chronic hepatic inflammation, could be the expression of the negative impact on periodontal disease. The study included chronic periodontitis patients who were systemically healthy, chronic periodontitis patients suffering from chronic hepatitis C, as well as control patients, being systemically and periodontally healthy. After periodontal examination and the assessment of certain periodontal parameters, gingival crevicular fluid was collected from all participating patients. By using the enzyme-linked immunosorbent assay method, a quantitative assessment of IL-1α and IL-1β levels was possible. The immunologic results were correlated to the clinical periodontal data. The gingival fluid levels of cytokines were higher for periodontitis patients with chronic hepatitis C than for the systemically healthy periodontitis patients (1.8-fold higher for IL-1α and 2.1-fold higher for IL-1β). In addition, the gingival fluid cytokine levels were significantly higher for the periodontal patients (with/without chronic hepatitis C) than for the control group. Positive correlations were found between gingival fluid IL-1α and IL-1β levels and certain clinical periodontal parameters or the age of the viral hepatitis C diagnosis, in periodontitis patients with chronic hepatitis C. The chronic hepatic inflammation may have an important additional negative impact on the periodontal status, as both inflammatory reactions seem to be promoted by common pro-inflammatory cytokines.