Identification of periodontal pathogens in atheromatous plaques

The Gut Microbiome Affects Atherosclerosis by Regulating Reverse Cholesterol Transport

The human system's secret organ, the gut microbiome, has received considerable attention. Emerging research has yielded substantial scientific evidence indicating that changes in gut microbial composition and microbial metabolites may contribute to the development of atherosclerotic cardiovascular disease. The burden of cardiovascular disease on healthcare systems is exacerbated by atherosclerotic cardiovascular disease, which continues to be the leading cause of mortality globally. Reverse cholesterol transport is a powerful protective mechanism that effectively prevents excessive accumulation of cholesterol for atherosclerotic cardiovascular disease. It has been revealed how the gut microbiota modulates reverse cholesterol transport in patients with atherosclerotic risk. In this review, we highlight the complex interactions between microbes, their metabolites, and their potential impacts in reverse cholesterol transport. We also explore the feasibility of modulating gut microbes and metabolites to facilitate reverse cholesterol transport as a novel therapy for atherosclerosis.

Gut Microbiome and Its Role in Valvular Heart Disease: Not a "Gutted" Relationship

The role of the gut microbiome (GM) and oral microbiome (OM) in cardiovascular disease (CVD) has been increasingly being understood in recent years. It is well known that GM is a risk factor for various CVD phenotypes, including hypertension, dyslipidemia, heart failure and atrial fibrillation. However, its role in valvular heart disease (VHD) is less well understood. Research shows that, direct, microbe-mediated and indirect, metabolite-mediated damage as a result of gut dysbiosis and environmental factors results in a subclinical, chronic, systemic inflammatory state, which promotes inflammatory cell infiltration in heart valves and subsequently, via pro-inflammatory molecules, initiates a cascade of reaction, resulting in valve calcification, fibrosis and dysfunction. This relationship between GM and VHD adds a pathophysiological link to the pathogenesis of VHD, which can be aimed therapeutically, in order to prevent or regress any risk for valvular pathologies. Therapeutic interventions include dietary modifications and lifestyle interventions, in order to influence environmental factors that can promote gut dysbiosis. Furthermore, the combination of probiotics and prebiotics, as well as fecal m transplantation and targeted treatment with inducers or inhibitors of microbial enzymes have showed promising results in animal and/or clinical studies, with the potential to reduce the inflammatory state and restore the normal gut flora in patients. This review, thus, is going to discuss the pathophysiological links behind the relationship of GM, CVD and VHD, as well as explore the recent data regarding the effect of GM-altering treatment in CVD, cardiac function and systemic inflammation.

Interaction between hypertension and periodontitis

OBJECTIVE

The possible association between hypertension and periodontitis and the effect of hypertension on periodontal treatment were investigated by evaluating salivary and gingival crevicular fluid (GCF) interleukin (IL)-6 and C reactive protein (CRP) levels.

METHODS

Forty-two healthy individuals without any previously diagnosed systemic disease [10 periodontally healthy (control) and 10 periodontitis (CP)] and subjects with hypertension [13 periodontally healthy (HP) and 9 with periodontitis (CP + HP)] participated in the study. GCF and saliva samples were obtained at baseline and 4 weeks after Phase I periodontal treatment. Biochemical parameters were analyzed using ELISA.

RESULTS

Before the periodontal treatment, significantly higher GCF IL-6 and CRP levels were detected in CP + HP and CP groups compared to HP and control groups (p < 0.01). Salivary CRP level in CP + HP group was found to be higher than the control group (p < 0.05). Statistically significant gingival and plaque index measurements (p < 0.01) might suggest a possible effect of hypertension on periodontal status. Periodontal treatment significantly improved the clinical indices; however, biochemical parameters did not change after the treatment.

CONCLUSION

The association of hypertension with periodontitis through local salivary and GCF inflammatory mediators might be possible in disease process.

Oral Health Clearance Outcomes for Cardiovascular Surgery

Objective

To determine the risk of morbidity and mortality in patients receiving dental extractions before planned cardiovascular surgery (CVS) and examine factors that may affect the chance of oral health clearance.

Patients and Methods

A retrospective medical record review was performed of patients who underwent dental screening before CVS from January 1, 2015, to December 31, 2021, at a major medical institution. A total of 496 patients met the inclusion criteria and were divided into 2 groups. Group 1 patients were cleared to advance to planned CVS (n=390). Group 2 patients were not cleared for surgery and subsequently underwent dental extractions before planned CVS (n=106).

Results

Six patients (5.7%) experienced postoperative complications after dental extraction that resulted in an emergency room visit. No deaths occurred after dental extraction before CVS. However, 4 patients died within 30 days of CVS, 3 from Group 1 (0.77%) and 1 from Group 2 (0.94%). Dental extraction before planned CVS showed a borderline significant association with death based on unadjusted (P=.06) and age-adjusted analysis (P=.05). Patients who reported seeing a dentist routinely had a significantly higher chance of oral health clearance (P <.001). No differences were noted between the 2 groups with regard to age, sex, or 30-day hospital readmission rate.

Conclusion

Patients who had dental extractions completed before planned CVS may be at an increased risk of mortality. Further studies are needed to examine this relationship. Emphasis should be on prioritization of routine dental visits before planned CVS.

The Impact of Periodontal Inflammation on the Severity of Coronary Atherosclerosis

Introduction Through plausible biological mechanisms, periodontitis causes systemic inflammatory burden and response, thus resulting in damage far beyond the oral cavity. Studies have demonstrated periodontitis to be a significant risk factor for coronary heart disease (CHD) and stroke. The larger the quantum of periodontal inflamed tissue, the greater the chances of periodontitis eliciting bacteremia and systemic inflammatory responses. Studies have reported that periodontitis and other common oral infections play an important role in the development of atherosclerosis. Therefore, the quantity of inflamed periodontal tissue assumes significance in determining the severity of atherosclerosis. Hence, this study investigates the impact of periodontal inflamed surface area (PISA) on the severity of coronary atherosclerosis. Materials and methods In this cross-sectional study, a total of 160 patients who presented at the department of periodontics of The British University in Egypt (BUE) from 1 January 2023 to 30 September 2023 were enrolled. Patients were only enrolled if they had undergone coronary angiography within the last six months, were less than 60 years of age, shared their previous medical history and coronary angiographic report, and gave informed written consent. Data on classic coronary risk factors and periodontal inflammatory status and angiographic findings were recorded and subjected to appropriate statistical analysis. Results The results revealed that the periodontal inflamed surface area (p = 0.002) apart from age (p < 0.047) and low-density lipoprotein cholesterol (LDL-C) (p < 0.001) is a significant independent predictor of the severity of coronary atherosclerosis. Conclusions The periodontal inflamed surface area is an independent predictor of the severity of coronary atherosclerosis.

Immunologic burden links periodontitis to acute coronary syndrome: levels of CD4 + and CD8 + T cells in gingival granulation tissue

OBJECTIVE

To investigate the proportional variation of macrophage and T-lymphocytes subpopulations in acute coronary syndrome (ACS) patients, its association with periodontitis (P), and to compare with control individuals.

SUBJECTS AND METHODS

Three groups of subjects participated: one group consisted of 17 ACS patients with P (ACS + P), another group consisted of 22 no ACS + P patients, and a control group consisted of 23 participants with gingivitis (no ACS + G). Macrophage, CD4 + , and CD8 + T-lymphocytes and CD4 + /CD8 + ratio values in gingival tissue were determined histometrically.

RESULTS

Significant differences were found among three groups regarding the mean number of macrophage (no ACS + P > ACS + P > no ACS + G; p < 0.05) and CD8 + T-lymphocytes (no ACS + P > ACS + P > no ACS + G; p < 0.05). Significant variations were observed between the groups both CD4 + T-lymphocytes densities (ACS + P > no ACS + P and ACS + P > no ACS + G; p < 0.05) and CD4 + / CD8 + ratio (no ACS + P < no ACS + G and ACS + P < no ACS + G; p < 0.05).

CONCLUSIONS

The increased number of CD8 + T-lymphocytes in both group ACS + P and group no ACS + P resulted in a reduction of the CD4 + /CD8 + ratio in gingival tissue when compared with no ACS + G group.

CLINICAL RELEVANCE

The decrease of CD4 + /CD8 + ratio in gingival tissue reflects periodontitis and may be associated with severe adverse outcomes in people with ACS.

Current trends and spatial-temporal dynamics of veterinary dentistry research: A scientometric study

Background and Aim

Understanding dental care in dogs has made remarkable progress in veterinary medicine. Therefore, this study aimed to analyze the academic literature published in veterinary dentistry from 1990 to 2023.

Materials and Methods

A descriptive study was conducted using a scientometric approach and metadata from the Web of Science database. A search strategy adapted for this database was developed using MeSH and Emtree terms and the Boolean operators AND and OR. Using Bibliometrix, different metrics were evaluated to assess the scientific production of researchers and institutions and the impact of authors based on their publications. CiteSpace was also used for co-citation analysis and visualization of citation networks, trends, and patterns in this field of study over time.

Results

The bibliometric study analyzed 211 documents from 50 different sources from 1990 to 2023, with an annual growth rate of 6.5%, covering the period 1990-2023. A total of 474 authors were identified, with an average of 2.82 coauthors per paper and 11.85% international coauthorships. The average age of the papers was 12.4 years and 4.55 citations per paper. The most common types of documents were articles (154 documents).

Conclusion

Research in veterinary dentistry has shown steady growth from 1990 to 2023. Although there have been fluctuations in article production over the years, there has been a steady growth in article production in veterinary dentistry in general. The annual average number of citations per article has varied over the years, reaching 45 in 2015. However, the average number of citations per article has decreased significantly from 2021 to 2023.

Coronary atherosclerosis and periodontitis have similarities in their clinical presentation

Background

Periodontitis (PE) and coronary heart disease (CHD) possess multiple mechanisms for a putative association. This case-control study compared the periodontal status among CHD subjects to controls without CHD, while also investigating atheroma invasion by known periodontal pathogens.

Methods

161 subjects participated in this study were divided into three CHD groups: No CHD, chronic CHD, acute CHD. Additional analysis involved grouping subjects according to number of atheromas: no atheroma, 1-4 atheromas, 5-18 atheromas. Data were collected from medical records, periodontal examinations, and questionnaires that included demographic, behavioral, and oral health variables. Angiographic catheterizations were analyzed according to the number of atheroma lesions, lesion size, lesion location, and atheroma lesion stability. Lipoprotein profile, inflammatory markers and cells were analyzed. The microbiological branch added 30 individuals who had their atheroma lesion and subgingival plaque analyzed using polymerase chain reaction probes against the 16 s region, red complex and Aggregatibacter actinomycetemcomitans' DNA.

Results

Subjects with CHD had high levels of systemic inflammatory markers and low levels of high-density lipoproteins compared to subjects without CHD. Subjects without CHD and clear coronaries had a prevalence of mild CAL, while individuals with more atheroma lesions had advanced CAL and more active PE. Subjects with more advanced CAL were 4 times more likely to have CHD compared to subjects with less, which is comparable to smoking. Only 4 subjects had the screened pathogens detected in atheroma, although these subjects also have the screened pathogens in subgingival plaque. However, 80% of atheromas had bacteria.

Conclusions

CHD and PE showed similarities in progression while active PE led to more atheroma lesions that also tended to be larger in size.

Genetic support of the causal association between gut microbiota and peripheral artery disease: a bidirectional Mendelian randomization study

BACKGROUND

The causal relationship between gut microbiota and peripheral artery disease (PAD) is still not clear. In this research, we employed the Mendelian randomization (MR) technique to explore the potential causal connection between 211 gut microbiota species and PAD. We also investigated whether the causal effects operate in both directions.

METHODS

We used Genome-wide Association Studies (GWAS) summary statistics data from the MiBioGen and FinnGen consortia to conduct a two-sample MR analysis to explore the causal link between gut microbiota and PAD. Sensitivity analysis is conducted to assess the robustness of the MR results. In addition to that, reverse MR analysis was performed to examine the inverse causal relationship.

RESULTS

The inverse variance weighted (IVW) method provided evidence supporting a causal relationship between 9 specific gut microbiota taxa and PAD. The study findings indicated that family Family XI (OR=1.11, CI 1.00-1.24, P=0.048), genus Lachnoclostridium (OR=1.24, 1.02-1.50, P=0.033), and genus Lachnospiraceae UCG001 (OR=1.17, 1.01-1.35, P=0.031) are risk factors associated with PAD. class Actinobacteria (OR=0.84, 0.72-0.99, P=0.034), family Acidaminococcaceae (OR=0.80, 0.66-0.98, P=0.029), genus Coprococcus2 (OR=0.79, 0.64-0.98, P=0.029), genus Ruminococcaceae UCG004 (OR=0.84, 0.72-0.99, P=0.032), genus Ruminococcaceae UCG010 (OR=0.74, 0.58-0.96, P=0.022), and order NB1n (OR=0.88, 0.79-0.98, P=0.02) may be associated with the risk factors of PAD. Moreover, our analysis did not uncover any evidence of a reverse causal relationship between PAD and the nine specific gut microbiota taxa investigated.

CONCLUSIONS

Our MR research has confirmed the potential causal relationship between gut microbiota and PAD while also identifying specific gut bacterial communities associated with PAD.

The oral microbial odyssey influencing chronic metabolic disease

INTRODUCTION

Since the oral cavity is the gateway to the gut, oral microbes likely hold the potential to influence metabolic disease by affecting the gut microbiota.

METHOD

A thorough review of literature has been performed to link the alterations in oral microbiota with chronic metabolic disease by influencing the gut microbiota.

RESULT

A strong correlation exists between abnormalities in oral microbiota and several systemic disorders, such as cardiovascular disease, diabetes, and obesity, which likely initially manifest as oral diseases. Ensuring adequate oral hygiene practices and cultivating diverse oral microflora are crucial for the preservation of general well-being. Oral bacteria have the ability to establish and endure in the gastrointestinal tract, leading to the development of prolonged inflammation and activation of the immune system. Oral microbe-associated prophylactic strategies could be beneficial in mitigating metabolic diseases.

CONCLUSION

Oral microbiota can have a profound impact on the gut microbiota and influence the pathogenesis of metabolic diseases.

Alterations of the salivary microbiota in gastroesophageal reflux disease

OBJECTIVES

Gastroesophageal reflux disease (GERD) is among the most prevalent gastrointestinal disorders. The oral microbiota plays an important role in human health and may be altered by the presence of GERD. Here, we aimed to investigate the alterations of salivary microbiota in GERD patients.

METHODS

We collected clinical information and salivary samples from 60 individuals. All participants underwent combined pH/impedance monitoring measurement and submitted samples for salivary microbiota sequencing. According to acid exposure time and DeMeester score, participants were divided into two groups: GERD + (Group G) and GERD - (Group C).

RESULTS

There was no significant difference in alpha diversity between study groups. Regarding beta diversity, principal coordinate analysis plots indicated that the microbiota composition data of the participants were grouped within partial overlapping clusters. The statistical analysis of the distance matrices was performed using the Adonis test (p = 0.017). Based on linear discriminant analysis effect size, the relative abundances of the phylum Bacteroidetes, class Bacteroidia, order Bacteroidales, family Prevotellaceae, and genus unidentified_Prevotellaceae were enriched in Group G. Compared with Group C, the phylum Actinobacteria, classes unidentified_Actinobacteria and Bacilli, orders Micrococcales and Lactobacillales, families Micrococcaceae and Streptococcaceae, and genuses Rothia and Streptococcus were decreased in Group G. At the genus level, the abundances of Streptococcus and Rothia were negatively correlated with DeMeester score and acid exposure time.

CONCLUSIONS

This study revealed alterations of the salivary microbiota in GERD patients, suggesting that acid reflux changes the oral ecosystem.

Targeting gut microbiota in aging-related cardiovascular dysfunction: focus on the mechanisms

The global population is aging and age-related cardiovascular disease is increasing. Even after controlling for cardiovascular risk factors, readmission and mortality rates remain high. In recent years, more and more in-depth studies have found that the composition of the gut microbiota and its metabolites, such as trimethylamine N-oxide (TMAO), bile acids (BAs), and short-chain fatty acids (SCFAs), affect the occurrence and development of age-related cardiovascular diseases through a variety of molecular pathways, providing a new target for therapy. In this review, we discuss the relationship between the gut microbiota and age-related cardiovascular diseases, and propose that the gut microbiota could be a new therapeutic target for preventing and treating cardiovascular diseases.

Periodontitis and atherosclerotic cardiovascular disease: A critical appraisal

In spite of intensive research efforts driving spectacular advances in terms of prevention and treatments, cardiovascular diseases (CVDs) remain a leading health burden, accounting for 32% of all deaths (World Health Organization. "Cardiovascular Diseases (CVDs)." WHO, February 1, 2017, https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds)). Cardiovascular diseases are a group of disorders affecting the heart and blood vessels. They encompass a collection of different conditions, among which atherosclerotic cardiovascular disease (ASCVD) is the most prevalent. CVDs caused by atherosclerosis, that is, ASCVD, are particularly fatal: with heart attack and stroke being together the most prevalent cause of death in the world. To reduce the health burden represented by ASCVD, it is urgent to identify the nature of the "residual risk," beyond the established risk factors (e.g., hypertension) and behavioral factors already maximally targeted by drugs and public health campaigns. Remarkably, periodontitis is increasingly recognized as an independent cardiovascular risk factor.

Protective effects of tanshinone IIA on Porphyromonas gingivalis-induced atherosclerosis via the downregulation of the NOX2/NOX4-ROS mediation of NF-κB signaling pathway

Tanshinone IIA (TSA), an active component isolated from Danshen, possess high medicinal values against atherosclerosis by reducing vascular oxidative stress, inhibiting platelet aggregation, and protecting the endothelium from damage. The periodontal pathogen Porphyromonas gingivalis (P. gingivalis) has been proven to accelerate the development of atherosclerosis. We aim to determine the effects of TSA on P. gingivalis-induced atherosclerosis in ApoE-knockout (ApoE-/-) mice. After feeding with a high-lipid diet and infected with P. gingivalis three times per week for four weeks, TSA-treated (60 mg/kg/d) mice greatly inhibited atherosclerotic lesions both morphologically and biochemically and exhibited significantly reduction ROS, 8-OHdG, and ox-LDL levels in serum compared with P. gingivalis-infected mice. Additionally, TSA-treated mice were observed a marked reduction of ROS, 8-OHdG and ox-LDL in the serum, mRNA levels of COX-2, LOX-1, NOX2 and NOX4 in the aorta, as well as the levels of NOX2, NOX4, and NF-κB. These results suggest that TSA attenuates oxidative stress by decreasing NOX2 and NOX4 and downregulating NF-κB signaling pathway, which might be contributed to the amelioration of atherosclerosis.

Disruption of Histamine-H1R signaling exacerbates cardiac microthrombosis after periodontal disease via TLR4/NFκB-p65 pathway

Periodontal disease is a chronic inflammatory disease that is highly correlated with cardiovascular disease(CVD). Histamine has been proven to participate in the pathophysiological processes of cardiovascular disease and oral inflammation. However, the role of histamine in the development of cardiac microthrombosis caused by periodontal disease has not been fully elucidated. We established a murine periodontal inflammation model by injecting lipopolysaccharide (LPS) or Porphyromonas gingivalis (P. gingivalis). In order to examine the effect of histamine/H1R signaling on cardiac injury after periodontal disease, we used histidine decarboxylase- knockout (HDC-/-) mice and histamine 1 receptor (H1R) antagonist. Our results demonstrated that LPS-induced periodontal inflammation significantly increased CD11b+Gr-1+ neutrophils in the peripheral blood and myocardial interstitium. Histamine deficiency resulted in further increases in P. gingivalis, neutrophils, inflammatory cytokines, and cardiac microthrombosis in the myocardium of HDC-/- mice compared to wild-type (WT) mice. Mechanistic analysis showed that blocking H1R could synergistically interact with LPS, further increasing the phosphorylation of p65, exacerbating the inflammatory response of neutrophils and endothelial cell damage. Conclusively, the disruption of histamine-H1R signaling exacerbates cardiac microthrombosis after periodontal disease via TLR4/NFκB-p65 pathway. Our findings not only reveal a link between periodontal inflammation and myocardial injury but also provided some thoughts for the use of H1R antagonist in clinical practice.

Effectiveness of subgingival irrigation and powered toothbrush as home care maintenance protocol in type 2 diabetic patients with active periodontal disease: A 4-month randomized controlled trial

Background

There is a bidirectional link between diabetes and periodontal disease. Control of active periodontal infection is an essential requisite to maintain optimal oral and systemic health in diabetic patients. The purpose of this study was to evaluate the efficacy of subgingival irrigation and powered toothbrush as home care maintenance protocol in type 2 diabetic patients with active periodontal disease compared to routine oral hygiene.

Materials and Methods

Forty (n = 40) diabetic (HbA1c >7%) patients were enrolled in this parallel, examiner-blind, interventional clinical trial. Patients were randomized into two groups: Group A (sonic toothbrush and irrigation with water twice daily) or Group B (manual toothbrush and mouth rinsing with 0.12% Chlorhexidine gluconate (CHX) twice daily)). All patients received Phase I therapybefore the start of the study. Clinical parameters (plaque index [PI], gingival index [GI], oral hygiene index [OHI], pocket depth [PD], clinical attachment level [CAL], and bleeding index [BI]) were assessed at baseline, 1, 2, and 4 months. Levels of C-reactive protein (CRP), HbA1c, and interleukin (IL)-1 β were assessed at baseline and 4 months only. Verbal and written instructions were provided to each subject specific to their intervention allocation. Descriptive, parametric, and nonparametric analyses were used where appropriate.

Results

Sixteen (n = 16) patients in Group A and fifteen (n = 15) patients in Group B completed the 4-month study. Both groups showed a significant difference in BI, PD, CAL, and HbA1c from baseline to 4 months. There were no differences within groups for OHI, GI, or PI and CRP, IL-1 β. The results are based on an underpowered study due to the drop out of 9 patients reducing the number below the needed 19 patients per group based on the power analysis.

Conclusion

Results from this study provide information for future studies on self-care regimens for individuals living with Type 2 diabetes.

Current status and future prospects of stomatology research

Research in stomatology (dental medicine) continues to expand globally and is oriented towards solving clinical issues, focusing on clarifying the clinical relevance and potential mechanisms of oral‍-‍systemic connections via clinical epidemiology, oral microecological characterization, and the establishment of animal models. Interdisciplinary integration of materials science and tissue engineering with stomatology is expected to lead to the creation of innovative materials and technologies to better resolve the most prevalent and challenging clinical issues such as peri-implantitis, soft and hard tissue defects, and dentin hypersensitivity. With the rapid development of artificial intelligence (AI), 5th generation mobile communication technology (5G), and big data applications, "intelligent stomatology" is emerging to build models for better clinical diagnosis and management, accelerate the reform of education, and support the growth and advancement of scientific research. Here, we summarized the current research status, and listed the future prospects and limitations of these three aspects, aiming to provide a basis for more accurate etiological exploration, novel treatment methods, and abundant big data analysis in stomatology to promote the translation of research achievements into practical applications for both clinicians and the public.

Expanding germ-organ theory: Understanding non-communicable diseases through enterobacterial translocation

Diverse microbial communities colonize different habitats of the human body, including gut, oral cavity, nasal cavity and tissues. These microbial communities are known as human microbiome, plays a vital role in maintaining the health. However, changes in the composition and functions of human microbiome can result in chronic low-grade inflammation, which can damage the epithelial cells and allows pathogens and their toxic metabolites to translocate into other organs such as the liver, heart, and kidneys, causing metabolic inflammation. This dysbiosis of human microbiome has been directly linked to the onset of several non-communicable diseases. Recent metabolomics studies have revealed that pathogens produce several uraemic toxins. These metabolites can serve as inter-kingdom signals, entering the circulatory system and altering host metabolism, thereby aggravating a variety of diseases. Interestingly, Enterobacteriaceae, a critical member of Proteobacteria, has been commonly associated with several non-communicable diseases, and the abundance of this family has been positively correlated with uraemic toxin production. Hence, this review provides a comprehensive overview of Enterobacterial translocation and their metabolites role in non-communicable diseases. This understanding may lead to the identification of novel biomarkers for each metabolic disease as well as the development of novel therapeutic drugs.

Periodontitis exacerbates atherosclerosis through Fusobacterium nucleatum-promoted hepatic glycolysis and lipogenesis

AIMS

Positive associations between periodontitis (PD) and atherosclerosis have been established, but the causality and mechanisms are not clear. We aimed to explore the causal roles of PD in atherosclerosis and dissect the underlying mechanisms.

METHODS AND RESULTS

A mouse model of PD was established by ligation of molars in combination with application of subgingival plaques collected from PD patients and then combined with atherosclerosis model induced by treating atheroprone mice with a high-cholesterol diet (HCD). PD significantly aggravated atherosclerosis in HCD-fed atheroprone mice, including increased en face plaque areas in whole aortas and lesion size at aortic roots. PD also increased circulating levels of triglycerides and cholesterol, hepatic levels of cholesterol, and hepatic expression of rate-limiting enzymes for lipogenesis. Using 16S ribosomal RNA (rRNA) gene sequencing, Fusobacterium nucleatum was identified as the most enriched PD-associated pathobiont that is present in both the oral cavity and livers. Co-culture experiments demonstrated that F. nucleatum directly stimulated lipid biosynthesis in primary mouse hepatocytes. Moreover, oral inoculation of F. nucleatum markedly elevated plasma levels of triglycerides and cholesterol and promoted atherogenesis in HCD-fed ApoE-/- mice. Results of RNA-seq and Seahorse assay indicated that F. nucleatum activated glycolysis, inhibition of which by 2-deoxyglucose in turn suppressed F. nucleatum-induced lipogenesis in hepatocytes. Finally, interrogation of the molecular mechanisms revealed that F. nucleatum-induced glycolysis and lipogenesis by activating PI3K/Akt/mTOR signalling pathway in hepatocytes.

CONCLUSIONS

PD exacerbates atherosclerosis and impairs lipid metabolism in mice, which may be mediated by F. nucleatum-promoted glycolysis and lipogenesis through PI3K/Akt/mTOR signalling in hepatocytes. Treatment of PD and specific targeting of F. nucleatum are promising strategies to improve therapeutic effectiveness of hyperlipidaemia and atherosclerosis.

Influence of Bariatric Surgery on Oral Microbiota: A Systematic Review

The study aims to systematically review the available literature to evaluate the changes in oral microbiota in patients after bariatric surgery (BS) and correlates these alterations in microorganisms with common oral manifestations. Relevant Electronic databases were systematically searched for indexed English literature. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed for framework designing, application, and reporting of the current systematic review. The focused PICO question was: "Is there any change in oral microbiota (O) of patients (P) who underwent BS (I) when compared with non-BS groups (C)?' Seven articles were selected for qualitative synthesis. On application of the National Institutes of Health (NIH) quality assessment tool, six studies were found to be of fair quality and one was of good quality. All the seven included studies evaluated the effect of BS on oral microbiota in humans. The outcomes of this review suggest that considerable changes take place in oral microbiota after BS which can be correlated with common oral manifestations. These changes are mainly due to the indirect effect of BS and may vary with the individuals. Due to variations in the included studies, it is difficult to proclaim any persistent pattern of oral microbiota found after BS.

Periodontitis and cardiovascular risk factors in subjects with and without type 1 diabetes: A cross sectional analysis

AIMS

This cross-sectional analysis explored the relationships between periodontal disease (PD) and subclinical CVD in a cohort of patients with type 1 diabetes and non-diabetic controls.

METHODS

Data were collected from adults enrolled in the Coronary Artery Calcification in Type 1 Diabetes (CACTI) study or enrolled through the Barbara Davis Center for Diabetes Adult Clinic. A clinical periodontal exam measured attachment loss and probing depth. Brachial artery distensibility (brachD), carotid intima-media thickness (cIMT), and pulse wave velocity (PWV) were assessed as measures of subclinical cardiovascular structure and function.

RESULTS

144 participants with T1D and 148 non-diabetics were enrolled. Compared to non-diabetic controls, T1D participants had a higher probing depth (2.6 mm vs. 2.5 mm; p = 0.04), higher attachment loss (2.7 mm vs. 2.4 mm; p < 0.01), lower brachD (mean 5.8 vs. 6.4 mmHg; p < 0.01), a higher cIMT (mean 0.68 vs. 0.64 mm; p < 0.01), and a higher PWV (mean 8.3 vs. 7.8 m/s; p < 0.01). There were no significant associations between PD and CVD metrics.

CONCLUSIONS

Periodontal and cardiovascular health was worse in participants with T1D compared to non-diabetics. No significant associations between PD measures and CVD were identified.

Oral pathogen aggravates atherosclerosis by inducing smooth muscle cell apoptosis and repressing macrophage efferocytosis

Periodontitis imparting the increased risk of atherosclerotic cardiovascular diseases is partially due to the immune subversion of the oral pathogen, particularly the Porphyromonas gingivalis (P. gingivalis), by inducing apoptosis. However, it remains obscure whether accumulated apoptotic cells in P. gingivalis-accelerated plaque formation are associated with impaired macrophage clearance. Here, we show that smooth muscle cells (SMCs) have a greater susceptibility to P. gingivalis-induced apoptosis than endothelial cells through TLR2 pathway activation. Meanwhile, large amounts of miR-143/145 in P.gingivalis-infected SMCs are extracellularly released and captured by macrophages. Then, these miR-143/145 are translocated into the nucleus to promote Siglec-G transcription, which represses macrophage efferocytosis. By constructing three genetic mouse models, we further confirm the in vivo roles of TLR2 and miR-143/145 in P. gingivalis-accelerated atherosclerosis. Therapeutically, we develop P.gingivalis-pretreated macrophage membranes to coat metronidazole and anti-Siglec-G antibodies for treating atherosclerosis and periodontitis simultaneously. Our findings extend the knowledge of the mechanism and therapeutic strategy in oral pathogen-associated systemic diseases.

Cross-sectional characterization of renal function in cats with caudal stomatitis

OBJECTIVES

The objective of the study was to compare renal functional biomarkers in cats and in caudal stomatitis (CS) and in age-matched control cats.

METHODS

A cross-sectional, case-control study was conducted on 44 client-owned cats with CS that were prospectively enrolled and evaluated for a Comprehensive Oral Health Assessment and Treatment at one of four institutions. Renal function was assessed with measurement of serum creatinine, urea nitrogen, serum symmetric dimethylarginine, urinalysis, urine protein:creatinine ratio and urine protein electrophoresis. Affected gingiva was biopsied to confirm the diagnosis of stomatitis. Renal biochemical analyses from the experimental group were compared with those of 44 age-matched controls without CS enrolled prospectively or retrospectively after presenting to the primary institution for routine healthcare. Control cats were included if they were clinically stable, their chronic illnesses were well managed and minimal dental disease was present on examination. Renal biomarkers were compared between groups using a t-test or the Mann-Whitney U-test. Frequency of azotemia, proteinuria and the clinical diagnosis of renal disease were compared using Fisher's exact test.

RESULTS

Relative to the control group, cats in the CS group had significantly lower serum creatinine (P <0.001) and albumin concentrations (P <0.001), urine specific gravity (P = 0.024) and hematocrit (P = 0.003), and higher serum phosphorus (P <0.001), potassium (P <0.001) and globulin concentrations (P <0.001), white blood cell count (P <0.001) and urine protein:creatinine ratio (P = 0.009). There were no significant differences in serum symmetric dimethylarginine or urea nitrogen concentrations. No clinically significant findings were noted on urine protein electrophoresis. There were no significant differences in the frequency of azotemia, proteinuria or renal disease categories between the two groups.

CONCLUSIONS AND RELEVANCE

The present study does not demonstrate a significant difference in the frequency of kidney disease between cats with and without CS. Longitudinal evaluation is warranted to investigate the relationship between renal disease and CS.

Structural and enzymatic characterization of the sialidase SiaPG from Porphyromonas gingivalis

The sialidases, which catalyze the hydrolysis of sialic acid from extracellular glycoconjugates, are a group of major virulence factors in various pathogenic bacteria. In Porphyromonas gingivalis, which causes human periodontal disease, sialidase contributes to bacterial pathogenesis via promoting the formation of biofilms and capsules, reducing the ability for macrophage clearance, and providing nutrients for bacterial colonization. Here, the crystal structure of the P. gingivalis sialidase SiaPG is reported at 2.1 Å resolution, revealing an N-terminal carbohydrate-binding domain followed by a canonical C-terminal catalytic domain. Simulation of the product sialic acid in the active-site pocket together with functional analysis enables clear identification of the key residues that are required for substrate binding and catalysis. Moreover, structural comparison with other sialidases reveals distinct features of the active-site pocket which might confer substrate specificity. These findings provide the structural basis for the further design and optimization of effective inhibitors to target SiaPG to fight against P. gingivalis-derived oral diseases.

Role of the Gut Microbiome in the Development of Atherosclerotic Cardiovascular Disease

Atherosclerotic cardiovascular disease (ASCVD) is the primary cause of death globally, with nine million deaths directly attributable to ischemic heart diseases in 2020. Since the last few decades, great effort has been put toward primary and secondary prevention strategies through identification and treatment of major cardiovascular risk factors, including hypertension, diabetes, dyslipidemia, smoking, and a sedentary lifestyle. Once labelled “the forgotten organ”, the gut microbiota has recently been rediscovered and has been found to play key functions in the incidence of ASCVD both directly by contributing to the development of atherosclerosis and indirectly by playing a part in the occurrence of fundamental cardiovascular risk factors. Essential gut metabolites, such as trimethylamine N-oxide (TMAO), secondary bile acids, lipopolysaccharides (LPS), and short-chain fatty acids (SCFAs), have been associated with the extent of ischemic heart diseases. This paper reviews the latest data on the impact of the gut microbiome in the incidence of ASCVD.

A Systematic Review and Meta-Analysis of the Relationship between Receiving the Flu Vaccine with Acute Cerebrovascular Accident and Its Hospitalization in the Elderly

Background and Aims

In recent years, various studies have been conducted worldwide to investigate the relationship between receiving the flu vaccine with acute cerebrovascular accident or stroke and its hospitalization in the elderly; however, the results of these studies are contradictory. Therefore, this study was aimed at investigating the relationship between receiving the flu vaccine with stroke and its hospitalization in the elderly.

Methods

This study is a systematic review and meta-analysis of studies examining the relationship between receiving the flu vaccine with stroke and its hospitalization in the elderly during the years 1980 to 2021 which have been published in ISI Web of Science, Scopus PubMed, Cochrane, Science Direct, Google Scholar, and Embase. All analyses were performed by Stata 15, and the significance level in this study was considered <0.05.

Results

In the systematic search, 3088 articles were retrieved, considering the study criteria; finally, 14 studies were included in the meta-analysis. Based on the results of the meta-analysis, the odds ratio (OR) of occurrence and hospitalization of stroke compared to the nonvaccinated group in vaccine recipients is equal to 0.84 (95% confidence interval (CI): 0.78-0.90, P value ≤ 0.001). Publication bias was not observed in this study (P value = 0.101).

Conclusion

Getting the flu vaccine can reduce the risk of occurrence and hospitalization of stroke in the elderly by 16% (10%-22%). Therefore, receiving this vaccine as a preventive intervention for stroke in the elderly may be promising.

Protein interactome mapping of Porphyromonas gingivalis provides insights into the formation of the PorQ-Z complex of the type IX secretion system

Porphyromonas gingivalis is an anaerobic Gram-negative human oral pathogen highly associated with the more severe forms of periodontal disease. Porphyromonas gingivalis utilises the type IX secretion system (T9SS) to transport ∼30 cargo proteins, including multiple virulence factors, to the cell surface. The T9SS is a multiprotein system consisting of at least 20 proteins, and recently, we characterised the protein interactome of these components. Similar to the T9SS, almost all biological processes are mediated through protein-protein interactions (PPIs). Therefore, mapping PPIs is important to understand the biological functions of many proteins in P. gingivalis. Herein, we provide native migration profiles of over 1000 P. gingivalis proteins. Using the T9SS, we demonstrate that our dataset is a useful resource for identifying novel protein interactions. Using this dataset and further analysis of T9SS P. gingivalis mutants, we discover new mechanistic insights into the formation of the PorQ-Z complex of the T9SS. This dataset is a valuable resource for studies of P. gingivalis.

Relationship between carotid intima-media thickness and periodontal disease in a Japanese urban population with and without hypertension: The Suita Study

AIM

To investigate the association between periodontal disease and atherosclerosis and to examine whether the association is modified by hypertension status.

MATERIALS AND METHODS

In this cross-sectional study, 1472 Japanese individuals aged 50-79 years who underwent a medical check-up, dental examination, and carotid ultrasonography were studied. Carotid atherosclerosis was expressed as the maximum and mean carotid intima-media thickness (max-IMT, mean-IMT) and the presence of stenosis (≥75%). Periodontal status was examined by the Community Periodontal Index (CPI, codes 0-4). The participants were divided into three groups according to the periodontal status (CPI0-2, CPI3, CPI4).

RESULTS

A positive correlation was found between mean-IMT and periodontal disease after adjustment for cardiovascular risk factors in the entire cohort (mean-IMT in hypertensives: CPI0-2: 0.848 mm, CPI3: 0.857 mm, CPI4: 0.877 mm; normotensives: 0.782, 0.802, 0.826). In the entire cohort, the multivariable-adjusted odds ratio of stenosis based on mean-IMT significantly increased according to periodontal status in normotensives (odds ratio; CPI0-2: 1, CPI3: 1.39, CPI4: 2.53; p-value for trend = .004) but showed only marginal significant increase in hypertensives (1, 1.15, 1.55; p-value for trend = .063). No significant relationships were observed for max-IMT in all analyses.

CONCLUSION

We observed an association between periodontal disease and atherosclerosis in normotensive and hypertensive participants.

Periodontitis and stroke: A Mendelian randomization study

BACKGROUND AND PURPOSE

Periodontitis has been implicated in the incidence of ischemic stroke. However, the generalizability of results to individuals with different subtypes of periodontitis is unknown. We aimed to investigate the causal relationship of chronic periodontitis (CP) and aggressive periodontitis (AgP) with ischemic stroke and its subtypes in the Mendelian randomization framework.

METHODS

The genetic proxies of CP were derived from large-scale summary statistics from the UK Biobank datasets (950 cases and 455,398 controls). The genetic associations of AgP were selected from another large genome-wide association study of European ancestry (851 cases and 6836 controls). The instruments of ischemic stroke (34,217 cases and 406,111 controls) and its subtypes were selected from the MEGASTROKE consortium of European ancestry. The inverse variant weighted method was performed to determine the causal inference and a comprehensive set of sensitivity analyses to test the robustness of the results.

RESULTS

In population-wide genetic analysis, there was no association of genetically predicted AgP (odds ratio [OR], 0.982; 95% confidence interval [CI], 0.956-1.009; p = .197) with ischemic stroke or its subtypes. For patients with CP, there was also no significant causal inference on ischemic stroke (OR, 1.017; 95% CI, 0.992-1.043; p = .184). However, regarding the stroke subtypes, the genetic analysis provided evidence of a causal relationship of CP with cardioembolic stroke (OR, 1.052; 95% CI, 1.002-1.104; p = .042), but not with large artery atherosclerosis (OR, 1.005; 95% CI, 0.944-1.069; p = .875) or small vessel occlusion (OR, 1.039; 95% CI, 0.981-1.101; p = .193).

CONCLUSION

This study suggested that there was a potential causal effect of CP on cardioembolic stroke.

Fusobacterium nucleatum and its associated systemic diseases: epidemiologic studies and possible mechanisms

Background

Fusobacterium nucleatum (F. nucleatum) is an anaerobic oral commensal and the major coaggregation bridge organism linking early and late colonisers. In recent years, a large number of studies suggest that F. nucleatum is closely related to the development of various systemic diseases, such as cardiovascular diseases, adverse pregnancy outcomes, inflammatory bowel diseases, cancer, Alzheimer's disease, respiratory infection, rheumatoid arthritis, etc.

Objective

To review the effect of F. nucleatum on systemic diseases and its possible pathogenesis and to open new avenues for prevention and treatment of F. nucleatum-associated systemic diseases.

Design

The research included every article published up to July 2022 featuring the keywords 'Systemic diseases' OR 'Atherosclerotic cardiovascular diseases' OR 'Atherosclerosis' OR 'Adverse pregnancy outcomes' OR 'Inflammatory bowel disease' OR 'Ulcerative colitis' OR 'Crohn’s disease' OR 'Cancers' OR 'Oral squamous cell carcinomas' OR 'Gastrointestinal cancers' OR 'Colorectal cancer' OR 'Breast cancer' OR 'Genitourinary cancers' OR 'Alzheimer’s disease ' OR 'Rheumatoid arthritis' OR 'Respiratory diseases' AND 'Fusobacterium nucleatum' OR 'Periodontal pathogen' OR 'Oral microbiota' OR 'Porphyromonas gingivalis' and was conducted in the major medical databases.

Results

F. nucleatum can induce immune response and inflammation in the body through direct or indirect pathways, and thus affect the occurrence and development of systemic diseases. Only by continuing to investigate the pathogenic lifestyles of F. nucleatum will we discover the divergent pathways that may be leveraged for diagnostic, preventive and therapeutic purposes.

Prevalence of Microorganisms in Atherosclerotic Plaques of Coronary Arteries: A Systematic Review and Meta-Analysis

Background

In this systematic review and meta-analysis, the existence of pathogens in atherosclerotic plaques of coronary arteries was investigated in coronary arteries diseases (CAD) patients.

Methods

This study was designed and implemented up to 31 August 2020. The findings present according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) checklist. Two independent reviewers (I.RJ and S.H) performed a comprehensive search on four different English databases including PubMed, ISI, Scopus, and Embase. In order to assess the quality of the articles, a checklist prepared by The Joanna Briggs Institute (JBI) was used.

Results

Finally, 44 studies were selected. The prevalence of different microorganisms in coronary arteries were as follows: Aggregatibacter actinomycetemcomitans (46.2%), Campylobacter rectus (43.0%), Chlamydia pneumonia (42.8%), Cytomegalovirus (29.1%), Helicobacter pylori (18.9%), Herpes simplex virus type 1 (5.9%), Porphyromonas gingivalis (42.6%), Prevotella intermedia (47.6%), Tannerella forsythia (43.7%), and Treponema denticola (32.9%).

Conclusion

Based on the result of this meta-analysis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans are the most common microorganisms in atherosclerotic plaques of coronary arteries and may have an important role in the development of atherosclerosis.

Gut Microbiota and Cardiovascular System: An Intricate Balance of Health and the Diseased State

Gut microbiota encompasses the resident microflora of the gut. Having an intricate relationship with the host, it plays an important role in regulating physiology and in the maintenance of balance between health and disease. Though dietary habits and the environment play a critical role in shaping the gut, an imbalance (referred to as dysbiosis) serves as a driving factor in the occurrence of different diseases, including cardiovascular disease (CVD). With risk factors of hypertension, diabetes, dyslipidemia, etc., CVD accounts for a large number of deaths among men (32%) and women (35%) worldwide. As gut microbiota is reported to have a direct influence on the risk factors associated with CVDs, this opens up new avenues in exploring the possible role of gut microbiota in regulating the gross physiological aspects along the gut-heart axis. The present study elaborates on different aspects of the gut microbiota and possible interaction with the host towards maintaining a balance between health and the occurrence of CVDs. As the gut microbiota makes regulatory checks for these risk factors, it has a possible role in shaping the gut and, as such, in decreasing the chances of the occurrence of CVDs. With special emphasis on the risk factors for CVDs, this paper includes information on the prominent bacterial species (Firmicutes, Bacteriodetes and others) towards an advance in our understanding of the etiology of CVDs and an exploration of the best possible therapeutic modules for implementation in the treatment of different CVDs along the gut-heart axis.

Involvement of Bacterial Extracellular Membrane Nanovesicles in Infectious Diseases and Their Application in Medicine

Bacterial extracellular membrane nanovesicles (EMNs) are attracting the attention of scientists more and more every year. These formations are involved in the pathogenesis of numerous diseases, among which, of course, the leading role is occupied by infectious diseases, the causative agents of which are a range of Gram-positive and Gram-negative bacteria. A separate field for the study of the role of EMN is cancer. Extracellular membrane nanovesicles nowadays have a practical application as vaccine carriers for immunization against many infectious diseases. At present, the most essential point is their role in stimulating immune response to bacterial infections and tumor cells. The possibility of nanovesicles' practical use in several disease treatments is being evaluated. In our review, we listed diseases, focusing on their multitude and diversity, for which EMNs are essential, and also considered in detail the possibilities of using EMNs in the therapy and prevention of various pathologies.

Exploring the Mechanisms and Association between Oral Microflora and Systemic Diseases

The scope of dentistry is ever-changing and dynamic in all fields of dentistry including periodontal health and disease. Recent studies show that oral health and systemic health are interdependent, particularly in the way that poor oral hygiene and periodontal health affect the systemic health of an individual and vice versa. Periodontal diseases are multifactorial in nature in which the role of bacterial infections is inevitable. Furthermore, high-throughput sequencing technologies have shed light on the dysregulation of the growth of oral microbial flora and their environment, including those that are associated with periodontitis and other oral and non-oral diseases. Under such circumstances, it becomes important to explore oral microbiota and understand the effects of periodontal pathogens in the pathogenesis of systemic diseases. In addition, it may strengthen our view that a better understanding of oral microbial flora and proper examination of the oral cavity may aid in the early diagnosis and possible treatment of systemic diseases and conditions. This will eventually lead to providing better care to our patients. Therefore, in this research, we attempt to outline the periodontal pathophysiology along with the role of periodontal pathogens in some commonly encountered systemic conditions.

Periodontal therapy for primary or secondary prevention of cardiovascular disease in people with periodontitis

BACKGROUND

There may be an association between periodontitis and cardiovascular disease (CVD); however, the evidence so far has been uncertain about whether periodontal therapy can help prevent CVD in people diagnosed with chronic periodontitis. This is the third update of a review originally published in 2014, and most recently updated in 2019. Although there is a new multidimensional staging and grading system for periodontitis, we have retained the label 'chronic periodontitis' in this version of the review since available studies are based on the previous classification system.

OBJECTIVES

To investigate the effects of periodontal therapy for primary or secondary prevention of CVD in people with chronic periodontitis.

SEARCH METHODS

An information specialist searched five bibliographic databases up to 17 November 2021 and additional search methods were used to identify published, unpublished, and ongoing studies. We also searched the Chinese BioMedical Literature Database, the China National Knowledge Infrastructure, the VIP database, and Sciencepaper Online to March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared active periodontal therapy to no periodontal treatment or a different periodontal treatment. We included studies of participants with a diagnosis of chronic periodontitis, either with CVD (secondary prevention studies) or without CVD (primary prevention studies).

DATA COLLECTION AND ANALYSIS

Two review authors carried out the study identification, data extraction, and 'Risk of bias' assessment independently and in duplicate. They resolved any discrepancies by discussion, or with a third review author. We adopted a formal pilot-tested data extraction form, and used the Cochrane tool to assess the risk of bias in the studies. We used GRADE criteria to assess the certainty of the evidence.

MAIN RESULTS

There are no new completed RCTs on this topic since we published our last update in 2019. We included two RCTs in the review. One study focused on the primary prevention of CVD, and the other addressed secondary prevention. We evaluated both as being at high risk of bias. Our primary outcomes of interest were death (all-cause and CVD-related) and all cardiovascular events, measured at one-year follow-up or longer. For primary prevention of CVD in participants with periodontitis and metabolic syndrome, one study (165 participants) provided very low-certainty evidence. There was only one death in the study; we were unable to determine whether scaling and root planning plus amoxicillin and metronidazole could reduce incidence of all-cause death (Peto odds ratio (OR) 7.48, 95% confidence interval (CI) 0.15 to 376.98), or all CVD-related death (Peto OR 7.48, 95% CI 0.15 to 376.98). We could not exclude the possibility that scaling and root planning plus amoxicillin and metronidazole could increase cardiovascular events (Peto OR 7.77, 95% CI 1.07 to 56.1) compared with supragingival scaling measured at 12-month follow-up. For secondary prevention of CVD, one pilot study randomised 303 participants to receive scaling and root planning plus oral hygiene instruction (periodontal treatment) or oral hygiene instruction plus a copy of radiographs and recommendation to follow-up with a dentist (community care). As cardiovascular events had been measured for different time periods of between 6 and 25 months, and only 37 participants were available with at least one-year follow-up, we did not consider the data to be sufficiently robust for inclusion in this review. The study did not evaluate all-cause death and all CVD-related death. We are unable to draw any conclusions about the effects of periodontal therapy on secondary prevention of CVD.

AUTHORS' CONCLUSIONS

For primary prevention of cardiovascular disease (CVD) in people diagnosed with periodontitis and metabolic syndrome, very low-certainty evidence was inconclusive about the effects of scaling and root planning plus antibiotics compared to supragingival scaling. There is no reliable evidence available regarding secondary prevention of CVD in people diagnosed with chronic periodontitis and CVD. Further trials are needed to reach conclusions about whether treatment for periodontal disease can help prevent occurrence or recurrence of CVD.

Periodontitis and implant complications in diabetes

Epidemiologic evidence indicates that periodontitis is more frequent in patients with uncontrolled diabetes mellitus than in healthy controls, suggesting that it could be considered the "sixth complication" of diabetes. Actually, diabetes mellitus and periodontitis are two extraordinarily prevalent chronic diseases that share a number of comorbidities all converging toward an increased risk of cardiovascular disease. Periodontal treatment has recently been shown to have the potential to improve the metabolic control of diabetes, although long-term studies are lacking. Uncontrolled diabetes also seems to affect the response to periodontal treatment, as well as the risk to develop peri-implant diseases. Mechanisms of associations between diabetes mellitus and periodontal disease include the release of advanced glycation end products as a result of hyperglycemia and a range of shared predisposing factors of genetic, microbial, and lifestyle nature. This review discusses the evidence for the risk of periodontal and peri-implant disease in diabetic patients and the potential role of the dental professional in the diabetes-periodontal interface.

Lipopolysaccharides and Cellular Senescence: Involvement in Atherosclerosis

Atherosclerosis is a chronic inflammatory disease of the vascular walls related to aging. Thus far, the roles of cellular senescence and bacterial infection in the pathogenesis of atherosclerosis have been speculated to be independent of each other. Some types of macrophages, vascular endothelial cells, and vascular smooth muscle cells are in a senescent state at the sites of atherosclerotic lesions. Likewise, bacterial infections and accumulations of lipopolysaccharide (LPS), an outer-membrane component of Gram-negative bacteria, have also been observed in the atherosclerotic lesions of patients. This review introduces the integration of these two potential pathways in atherosclerosis. Previous studies have suggested that LPS directly induces cellular senescence in cultured monocytes/macrophages and vascular cells. In addition, LPS enhances the inflammatory properties (senescence-associated secretory phenotype [SASP]) of senescent endothelial cells. Thus, LPS derived from Gram-negative bacteria could exaggerate the pathogenesis of atherosclerosis by inducing and enhancing cellular senescence and the SASP-associated inflammatory properties of specific vascular cells in atherosclerotic lesions. This proposed mechanism can provide novel approaches to preventing and treating this common age-related disease.

Association of peptidoglycan recognition protein 1 to post-myocardial infarction and periodontal inflammation: A subgroup report from the PAROKRANK (Periodontal Disease and the Relation to Myocardial Infarction) study

BACKGROUND

Peptidoglycan recognition protein 1 (PGLYRP1) is an antimicrobial and proinflammatory innate immunity protein activated during infections. We aimed to investigate whether PGYLRP1 and associated molecules of the immune response in saliva is a cumulative outcome result of both MI and periodontal inflammation.

METHODS AND RESULTS

Two hundred patients with MI and another 200 matched non-MI controls were included. A full-mouthexamination was conducted to assess periodontal inflammation and collection of stimulated saliva was performed 6 to 10 weeks after the first MI. PGLYRP1, triggering receptor expressed on myeloid cells 1 (TREM-1), interleukin-1 beta (IL-1β) were analyzed by ELISA. Matrix metalloproteinase (MMP)-8 levels were determined by IFMA. Compared to controls, MI patients showed higher salivary PGLYRP1, but not TREM-1 levels. The difference in PGLYRP1 levels remained after adjustment for covariates. In MI patients, the PGLYRP1 levels positively correlated with BOP and PPD 4 to 5 mm. Among non-MI subjects, the levels of PGLYRP1 correlated positively and significantly with BOP and total PPD. Salivary PGLYRP1 concentrations also showed strong positive correlations with levels of TREM-1, IL-1β and MMP-8. In multivariate linear regression analysis, in MI patients, BOP and former smokingstatus displayed an association with salivary PGLYRP1 concentration.

CONCLUSION

MI patients showed higher salivary PGLYRP1 levels than healthy controls, also after adjusting for smoking, sex, age and periodontal health status. Salivary levels of PGLYRP1 may reflect the overall inflammatory burden to chronic bacterial exposure, possibly underpinning the observed associations between periodontitis and exposure with MI.

Role of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 6 in activation of inflammation in human umbilical vein endothelial cells stimulated by Porphyromonas gingivalis-an in vitro study

Background/purpose

Porphyromonas gingivalis (P. gingivalis) could induce the activation of vascular endothelial cells and promote the formation of atherosclerosis. Nucleotide-binding oligomerization domain-like receptor family pyrin domain containing (NLRP) 6 could recognize P. gingivalis, but its role in atherosclerosis was unknown. The purpose of this study is to investigate the role of NLRP6 in the activation of inflammation in human umbilical vein endothelial cells (HUVECs) stimulated by P. gingivalis.

Materials and methods

The expression level of NLRP6 in HUVECs with or without P. gingivalis-challenge was observed. Down-regulating the expression of NLRP6 in HUVECs, the expression levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein (MCP)-1 were detected. Then, the HUVECs with NLRP6-overexpressed were stimulated by P. gingivalis, the levels of inflammatory cytokines above were examined and compared with those in HUVECs triggered by P. gingivalis only. To evaluate the effect of NLRP6 on bacterial immune escape, the NLRP6 was overexpressed, and the colonies of P. gingivalis that survived in HUVECs were calculated.

Results

NLRP6 was expressed in HUVECs and decreased after P. gingivalis stimulation. Downregulation of NLRP6 decreased the expression levels of IL-1β, IL-6, IL-8, TNF-α and MCP-1 in HUVECs. Those cytokines above in NLRP6-overexpressed HUVECs with P. gingivalis-stimulation significantly increased than in the cells with P. gingivalis-stimulation only. Furthermore, over-expression of NLRP6 decreased the colonies of P. gingivalis survival in HUVECs.

Conclusion

NLRP6 regulated the activation of inflammation in HUVECs triggered by P. gingivalis and played an important role in P. gingivalis survival in endothelial cells.

Pyroptosisin periodontitis: From the intricate interaction with apoptosis, NETosis, and necroptosis to the therapeutic prospects

Periodontitis is highly prevalent worldwide. It is characterized by periodontal attachment and alveolar bone destruction, which not only leads to tooth loss but also results in the exacerbation of systematic diseases. As such, periodontitis has a significant negative impact on the daily lives of patients. Detailed exploration of the molecular mechanisms underlying the physiopathology of periodontitis may contribute to the development of new therapeutic strategies for periodontitis and the associated systematic diseases. Pyroptosis, as one of the inflammatory programmed cell death pathways, is implicated in the pathogenesis of periodontitis. Progress in the field of pyroptosis has greatly enhanced our understanding of its role in inflammatory diseases. This review first summarizes the mechanisms underlying the activation of pyroptosis in periodontitis and the pathological role of pyroptosis in the progression of periodontitis. Then, the crosstalk between pyroptosis with apoptosis, necroptosis, and NETosis in periodontitis is discussed. Moreover, pyroptosis, as a novel link that connects periodontitis with systemic disease, is also reviewed. Finally, the current challenges associated with pyroptosis as a potential therapeutic target for periodontitis are highlighted.

Cross-sectional analysis of the association of periodontitis with carotid intima media thickness and atherosclerotic plaque in the Hamburg City health study

BACKGROUND

Previous epidemiological studies regarding the association between chronic periodontitis (CP) and carotid intima-media thickness (cIMT) and subclinical atherosclerosis have been inconclusive.

OBJECTIVE

The aim of this study was to determine whether CP is associated with subclinical atherosclerosis in a large population-based cohort study conducted in northern Germany (the Hamburg City Health study).

METHODS

Baseline data from 5781 participants of the Hamburg City Health Study with complete oral health and carotid ultrasound data (50.7% female, mean age: 62.1 ± 8.4 years) were evaluated. A standardized duplex sonography of the carotid artery was performed with measurement of carotid intima-media thickness (cIMT) and atherosclerotic plaques. Oral health was assessed by recording the decayed, missing, and filled teeth (DMFT) index, clinical attachment loss (CAL), bleeding on probing (BOP), and the dental plaque index (PI). Correlations were tested for statistical significance by means of descriptive statistics and multivariate regression analyses.

RESULTS

Moderate and severe CP were associated with the prevalence of cIMT ≥ 1 mm (none or mild CP: 5.1%, moderate CP: 6.1%, severe CP: 10%) and mean cIMT (none or mild CP: 0.72 mm, moderate CP: 0.75 mm, severe CP: 0.78 mm) in bivariate analyses (p < .001). Additionally, severe and moderate CP were associated with higher prevalence of carotid atherosclerotic plaques (plaque = yes: none or mild CP: 23.9%, moderate CP: 29%, severe CP: 40.2%,). After adjustment for age, sex, smoking, diabetes, hypertension, educational level, hypercholesterolemia, and hsCRP, severe CP still correlated significantly with cIMT and the prevalence of cIMT ≥1 mm and/or presence of carotid atherosclerotic plaques.

CONCLUSION

In this study, severe CP was associated with increased cIMT and higher prevalence of carotid plaques independent of common risk factors.

Periodontal disease measures and risk of incident peripheral artery disease: The Atherosclerosis Risk in Communities (ARIC) Study

BACKGROUND

The association of periodontal disease with atherosclerotic cardiovascular diseases is well known, but not specifically with incident peripheral artery disease (PAD). Therefore, we studied the associations of periodontal disease with incident PAD in a population-based setting.

METHODS

Among 9,793 participants (aged 53-75 years) without prevalent PAD, self-reported history of periodontal disease was ascertained. Of these, 5,872 participants underwent full-mouth examinations from which periodontal status was defined using the US Centers for Disease Control and Prevention-American Academy of Periodontology (CDC-AAP) definition. We quantified the association of periodontal disease with incident PAD (defined by hospital admission diagnosis or procedures) using multivariable Cox regression models.

RESULTS

During a median follow-up of 20.1 years, 360 participants (3.6%) developed PAD. In models accounting for potential confounders including diabetes and smoking pack-years, there was higher hazard of PAD in participants with self-reported tooth loss because of periodontal disease (hazard ratio:1.54 [95% CI:1.20-1.98]), history of periodontal disease treatment (1.37 [1.05-1.80]), and periodontal disease diagnosis (1.38 [1.09-1.74]), compared to their respective counterparts. The clinical measure of periodontal disease (n = 5,872) was not significantly associated with incident PAD in the fully adjusted model (e.g., 1.53 [0.94-2.50] in CDC-AAP-defined severe periodontal disease versus no disease).

CONCLUSION

We observed a modest association of self-reported periodontal disease, especially when resulting in tooth loss, with incident PAD in the general population. Nonetheless, a larger study with the clinical measure of periodontal disease is warranted.

Congenital Heart Diseases and Periodontal Diseases—Is There a Link?

An understanding in the field of periodontal medicine explains the fact that the oral cavity serves as a niche for numerous pathogenic microorganisms. When these microorganisms or their by-products disseminate to the various parts of the body, they are capable of triggering diseases characterized by an altered host immune-inflammatory response in the anatomically distinct organ. This mechanism is reported in the propagation of cardiovascular diseases with respect to periodontal medicine. Abundant amount of literature suggests an association between atherosclerotic cardiovascular disease and periodontal diseases. However, there is very less data available to highlight the association between periodontal disease and non-atherosclerotic cardiovascular disease, such as congenital anomalies of the heart. This review outlines the relationship between periodontal diseases and congenital heart diseases and also helps us understand whether the presence of periodontal disease can worsen the preexisting congenital cardiac disease.

Association Between Periodontal Disease and Cardiovascular Disease (from the NHANES)

As observational studies support the association between periodontal disease (PD) and cardiovascular diseases (CVDs), we examined this relationship using the National Health and Nutrition Examination Survey 2013 to 2014 data. This cross-sectional study involved 2,830 adult participants, aged ≥30 years who underwent a home interview, followed by a standardized assessment at a mobile examination center from 2013 to 2014. PD was defined using the new classification scheme issued by American Academy of Periodontology Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions in 2017, and CVD was defined as the composite of coronary artery disease and stroke. The gathered data were subjected to weighted statistical analysis to examine the relation between CVD prevalence and PD. The sample (mean age 51.5 ± 13.6 years) comprised 50.1% men and 69.5% White participants. Stage I (mild/subclinical), II (moderate), and III to IV (severe) PD was noted in 16.7% (95% confidence interval [CI] 12.7 to 21.7), 57.4% (95% CI 53.9 to 60.9), and 25.9% (95% CI 21.4 to 30.8) of the participants, respectively. Patients with stage III and IV PD were more likely to have CVD than those with stage I (adjusted odds ratio 3.59, 95% CI 1.12 to 11.54, p = 0.03). Similarly, participants who reported fair/poor gum health were more likely to have CVD than those who reported excellent/very good gum health (adjusted odds ratio 2.17, 95% CI 0.98 to 4.79, p = 0.055). In conclusion, the data from the National Health and Nutrition Examination Survey 2013 to 2014 demonstrated that PD severity is associated with CVD risk. However, the information gathered by trained professionals during periodontal examinations is a more reliable predictor of PD-CVD associations compared with self-reported measures of oral health.

Porphyromonas gingivalis lipopolysaccharide affects the angiogenic function of endothelial progenitor cells via Akt/FoxO1 signaling

AIMS

Endothelial progenitor cells (EPCs) function as the angiogenic switch of many physiological and pathological conditions. We aimed to investigate the effects of Porphyromonas gingivalis lipopolysaccharide on the angiogenic capacity of EPCs and delineate the underlying mechanisms.

MATERIALS AND METHODS

EPCs were isolated from human umbilical blood. CCK-8 assay was undertaken to analyze the cell viability. The migration and tube formation capacity were assessed by wound healing and tube formation, respectively. The protein expression of Akt/p-Akt, endothelial nitric oxide synthase (eNOS)/p-eNOS, and Forkhead box O1 (FoxO1)/p-FoxO1 was determined by Western blot. The intracellular localization of FoxO1 was evaluated by immunofluorescent staining.

RESULTS

P. gingivalis LPS at 10 μg/ml significantly increased the viability (10.9 ± 2.9%), migration (16.3 ± 3.1%), and tube formation (38.6 ± 5.5%) of EPCs, along with increased phosphorylation of Akt, eNOS, and FoxO1. Mechanistically, Akt inhibition by specific inhibitor wortmannin and FoxO1 forced expression by adenovirus transfection in EPCs markedly attenuated the P. gingivalis LPS-induced eNOS activation, tube formation, and migration. Moreover, P. gingivalis LPS-induced phosphorylation and nuclear exclusion of FoxO1 were blunted by Akt inhibition.

CONCLUSIONS

The present study suggests that P. gingivalis LPS could affect the angiogenic function of EPCs through the Akt/FoxO1 signaling. The current findings may shed light on the clinical association of periodontitis with aberrant angiogenesis seen in atherosclerotic plaque rupture.

SARS-CoV-2 and Prevotella spp.: friend or foe? A systematic literature review

During this global pandemic of the COVID-19 disease, a lot of information has arisen in the media and online without scientific validation, and among these is the possibility that this disease could be aggravated by a secondary bacterial infection such as Prevotella, as well as the interest or not in using azithromycin, a potentially active antimicrobial agent. The aim of this study was to carry out a systematic literature review, to prove or disprove these allegations by scientific arguments. The search included Medline, PubMed, and Pubtator Central databases for English-language articles published 1999-2021. After removing duplicates, a total of final eligible studies (n=149) were selected. There were more articles showing an increase of Prevotella abundance in the presence of viral infection like that related to Human Immunodeficiency Virus (HIV), Papillomavirus (HPV), Herpesviridae and respiratory virus, highlighting differences according to methodologies and patient groups. The arguments for or against the use of azithromycin are stated in light of the results of the literature, showing the role of intercurrent factors, such as age, drug consumption, the presence of cancer or periodontal diseases. However, clinical trials are lacking to prove the direct link between the presence of Prevotella spp. and a worsening of COVID-19, mainly those using azithromycin alone in this indication.

Proteomic analysis of the periodontal pathogen Prevotella intermedia secretomes in biofilm and planktonic lifestyles

Prevotella intermedia is an important species associated with periodontitis. Despite the remarkable clinical significance, little is known about the molecular basis for its virulence. The aim of this study was to characterize the secretome of P. intermedia in biofilm and planktonic life mode. The biofilm secretome showed 109 proteins while the planktonic secretome showed 136 proteins. The biofilm and the planktonic secretomes contained 17 and 33 signal-peptide bearing proteins, 13 and 18 lipoproteins, respectively. Superoxide reductase, sensor histidine kinase, C40 family peptidase, elongation factor Tu, threonine synthase etc. were unique to biofilm. Of the ~ 30 proteins with predicted virulence potential from biofilm and planktonic secretomes, only 6 were common between the two groups, implying large differences between biofilm and planktonic modes of P. intermedia. From Gene Ontology biofilm secretome displayed a markedly higher percent proteins compared to planktonic secretome in terms of cellular amino acid metabolic process, nitrogen compound metabolic process etc. Inflammatory cytokine profile analysis revealed that only the biofilm secretome, not the planktonic one, induced important cytokines such as MIP-1α/MIP-1β, IL-1β, and IL-8. In conclusion, the revealed differences in the protein profiles of P. intermedia biofilm and planktonic secretomes may trigger further questions about molecular mechanisms how this species exerts its virulence potential in the oral cavity.

Acute Myocardial Infarction and Periodontitis: Importance of Awareness and Prevention in Latin America

By 2030, non-communicable diseases will have accounted for more than three-quarters of deaths worldwide. Cardiovascular diseases (CVDs) have been the leading cause of death worldwide for several years. Acute myocardial infarction (AMI) is a CVD characterized by necrosis of the heart at the myocardial level due to prolonged ischemia caused by the reduction or sudden absence of coronary blood supply. The prevalence of AMI is higher in men at all ages. The incidence of AMI has decreased in industrialized nations; however, it has been on the rise in Latin America (LATAM) due to lifestyle changes. These changes have caused the combined incidence of CVDs and unresolved health concerns in LATAM, such as infections and malnutrition. It is well known that periodontitis, a highly prevalent chronic infectious inflammatory disease, has been associated with systemic diseases, such as diabetes, kidney diseases, and AMI. This review addresses proposed aspects of the correlation between periodontitis and AMI, explains the importance of preventing periodontitis and CVDs, and analyzes the preventative measures being implemented in LATAM, particularly in Mexico.

Maladaptive trained immunity and clonal hematopoiesis as potential mechanistic links between periodontitis and inflammatory comorbidities

Periodontitis is bidirectionally associated with systemic inflammatory disorders. The prevalence and severity of this oral disease and linked comorbidities increases with aging. Here, we review two newly emerged concepts, trained innate immunity (TII) and clonal hematopoiesis of indeterminate potential (CHIP), which together support a potential hypothesis on how periodontitis affects and is affected by comorbidities and why the susceptibility to periodontitis and comorbidities increases with aging. Given that chronic diseases are largely triggered by the action of inflammatory immune cells, modulation of their bone marrow precursors, the hematopoietic stem and progenitor cells (HSPCs), may affect multiple disorders that emerge as comorbidities. Such alterations in HSPCs can be mediated by TII and/or CHIP, two non-mutually exclusive processes sharing a bias for enhanced myelopoiesis and production of innate immune cells with heightened proinflammatory potential. TII is a state of elevated immune responsiveness based on innate immune (epigenetic) memory. Systemic inflammation can initiate TII in the bone marrow via sustained rewiring of HSPCs, which thereby display a skewing toward the myeloid lineage, resulting in generation of hyper-reactive or "trained" myeloid cells. CHIP arises from aging-related somatic mutations in HSPCs, which confer a survival and proliferation advantage to the mutant HSPCs and give rise to an outsized fraction of hyper-inflammatory mutant myeloid cells in the circulation and tissues. This review discusses emerging evidence that supports the notion that TII and CHIP may underlie a causal and age-related association between periodontitis and comorbidities. A holistic mechanistic understanding of the periodontitis-systemic disease connection may offer novel diagnostic and therapeutic targets for treating inflammatory comorbidities.