Infection or inflammation: the link between periodontal and cardiovascular diseases

Your health is in your mouth: A comprehensive view to promote general wellness

Background

Even though various studies recognize the importance of the oral cavity to have general health, in multidisciplinary professional practice it is almost always excluded and on an individual basis, very commonly neglected. Oral diseases are preventable, still, they are highly prevalent. Although some studies consider oral health within integral health, currently, there is no model in which the mouth is integrated within other levels for the achievement of well-being. The objective of this article was to review the importance of oral health and its connection with well-being and, based on these findings, propose a complex and comprehensive perspective for approach and care.

Methods

The databases MEDLINE, PubMed, and Google Scholar were revised for randomized controlled trials and reviews that included search terms related to oral health and its relationship with the general health in its different levels (physical, psychological, social and environmental).

Results

The review shows that oral health is critical, as the teeth and mouth are not only an integral part of the body, but also, they also support and enable essential human functions. That is, oral health has a multidimensional nature, as it includes the physical, psychological, social, and environmental domains that are essential for overall health and well-being. Likewise, the mouth is the psychological seat of the first physiological needs and emotional gratifications, with it we take a taste of the world around us. Thus, the mouth plays an important role in the feeling of unity and in the constitution of the self. Based on these results we propose an integrative model in which the mouth is the first step for well-being and from this integrative model we build a multidisciplinary approach which could be used in the clinical practice for the promotion of oral care and general health.

Conclusion

The effort on the part of oral health professionals is essential for people's well-being and must be integrated as part of health promotion. Dental treatments alone cannot solve this problem, it requires a comprehensive and approach in which the bio-psychological, behavioral, and socio-environmental determinants are included to face this global oral health challenge. That is, without a comprehensive and multidisciplinary approach to medical science that includes dental and oral health, our public policies cannot provide the best answers to health promotion, disease prevention, early detection, and treatment.

Photoacoustic imaging of posterior periodontal pocket using a commercial hockey-stick transducer

SIGNIFICANCE

Photoacoustic imaging has shown advantages over the periodontal probing method in measuring the periodontal probing depth, but the large size of conventional photoacoustic transducers prevents imaging of the more posterior teeth.

AIM

Our aim is to develop a photoacoustic imaging system to image the more posterior periodontal pocket.

APPROACH

We report a clinical "hockey-stick"-style transducer integrated with fibers for periodontal photoacoustic imaging. Cuttlefish ink labeled the periodontal pocket as the photoacoustic contrast agent.

RESULTS

We characterized the imaging system and then measured the pocket depth of 35 swine teeth. Three raters evaluated the performance of the hockey-stick transducer. The measurements between the Williams probing (gold standard) and the photoacoustic methods were blinded but highly correlated. We showed a bias of ∼0.3  mm for the imaging-based technique versus Williams probing. The minimum inter-reliability was over 0.60 for three different raters of varying experience, suggesting that this approach to measure the periodontal pocket is reproducible. Finally, we imaged three pre-molars of a human subject. We could access more upper and posterior teeth than conventional linear transducers.

CONCLUSIONS

The unique angle shape of the hockey-stick transducer allows it to image more posterior teeth than regular linear transducers. This study demonstrated the ability of a hockey-stick transducer to measure the periodontal pocket via photoacoustic imaging.

Unexpected Relationships: Periodontal Diseases: Atherosclerosis-Plaque Destabilization? From the Teeth to a Coronary Event

Simple Summary

Periodontal disease and atherosclerotic cardiovascular disease are very common around the world. Coronary artery disease is the leading cause of death. The main factor involved in the pathogenesis of atherosclerosis is inflammation. Therefore, a number of studies have indicated that periodontal disease (causes chronic inflammation) is a risk factor for the progression of atherosclerosis. The presence of periodontal pathogens has been found in human atherosclerotic plaques. A number of pathomechanisms have been demonstrated, thanks to which periodontal pathogens, especially Porphyromonas gingivalis, can directly increase the progression of atherosclerosis and the risk of cardiovascular disease. Observational studies found that patients with periodontal disease were at higher risk of developing atherosclerotic cardiovascular disease. Moreover, periodontal treatment leads to a reduction in cardiovascular risk therefore taking care of oral hygiene should be an important cardiovascular disease preventive measure.

Abstract

Atherosclerotic cardiovascular disease (ASCVD) and periodontal disease (PD) are global health problems. High frequency of ASCVD is associated with the spread of many risk factors, including poor diet, sedentary lifestyle, diabetes, hyperlipidemia, obesity, smoking, hypertension, chronic kidney disease, hypertension, hyperhomocysteinemia, hyperuricemia, excessive stress, virus infection, genetic predisposition, etc. The pathogenesis of ASCVD is complex, while inflammation plays an important role. PD is a chronic, multifactorial inflammatory disease caused by dysbiosis of the oral microbiota, causing the progressive destruction of the bone and periodontal tissues surrounding the teeth. The main etiological factor of PD is the bacteria, which are capable of activating the immune response of the host inducing an inflammatory response. PD is associated with a mixed microbiota, with the evident predominance of anaerobic bacteria and microaerophilic. The “red complex” is an aggregate of three oral bacteria: Tannerella forsythia Treponema denticola and Porphyromonas gingivalis responsible for severe clinical manifestation of PD. ASCVD and PD share a number of risk factors, and it is difficult to establish a causal relationship between these diseases. The influence of PD on ASCVD should be treated as a factor increasing the risk of atherosclerotic plaque destabilization and cardiovascular events. The results of observational studies indicate that PD significantly increases the risk of ASCVD. In interventional studies, PD treatment was found to have a beneficial effect in the prevention and control of ASCVD. This comprehensive review summarizes the current knowledge of the relationship between PD and ASCVD.

Analysis of Interaction Between Porphyromonas gingivalis and Endothelial Cells In Vitro

Chronic periodontitis is the most common periodontitis observed in adults. Recently, its association with systemic diseases such as ischemic heart-brain disease and diabetes has been pointed out. Porphyromonas gingivalis, a major causative bacterium of chronic periodontitis, has properties of adhering to blood vessels and inducing inflammation, and those properties are involved in the induction of vascular inflammation and promotion of atherosclerosis. Therefore, analysis of the interaction of P. gingivalis with vascular endothelial cells will contribute to an understanding of the link between periodontitis and vascular lesions.

Relationship between the burden of major periodontal bacteria and serum lipid profile in a cross-sectional Japanese study

Background

The association of periodontal bacteria with lipid profile alteration remains largely unknown, although it has been suggested that chronic periodontitis increases the atherosclerotic risk. This cross-sectional study investigated the relationship between the prevalence and total burden of periodontal bacteria and serum lipid profile.

Methods

Saliva from enrolled participants was collected to detect 4 major periodontal bacteria (Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Prevotella intermedia) using Polymerase Chain Reaction method. High-density lipoprotein (HDL) cholesterol, triglycerides (TG), and low-density lipoprotein cholesterol were assessed using blood samples. We compared the averages of each lipid in association with the prevalence of each bacterial species, their burden (low, moderate, and high), and the combination of bacterial burden and periodontal status, defined as periodontitis, using the Community Periodontal Index, after adjustment for other potential confounding factors, by employing general linear models with least square means.

Results

A total of 385 Japanese individuals (176 men, 209 women; mean age 69.2 years) were enrolled. The number of bacterial species and their co-existence with periodontitis were significantly related to a decrease in HDL (p for trend < 0.01) and increase in TG (p for trend = 0.04). The adjusted mean HDL levels (mg/dL) in individuals with low, moderate, and high levels of bacterial species were 66.1, 63.0, and 58.9, respectively, and those in the 6 groups defined by combination of the two factors were 67.9, 64.6, 64.3, 65.4, 61.5, and 54.7, respectively.

Conclusion

Periodontal bacterial burden is suggested to be independently involved in lowering serum HDL level. Our findings suggest that bacterial tests in a clinical setting could be a useful approach for predicting the risk of HDL metabolism dysregulation.

Human platelet activation by Escherichia coli: roles for FcγRIIA and integrin αIIbβ3

Gram-negative Escherichia coli cause diseases such as sepsis and hemolytic uremic syndrome in which thrombotic disorders can be found. Direct platelet–bacterium interactions might contribute to some of these conditions; however, mechanisms of human platelet activation by E. coli leading to thrombus formation are poorly understood. While the IgG receptor FcγRIIA has a key role in platelet response to various Gram-positive species, its role in activation to Gram-negative bacteria is poorly defined. This study aimed to investigate the molecular mechanisms of human platelet activation by E. coli, including the potential role of FcγRIIA. Using light-transmission aggregometry, measurements of ATP release and tyrosine-phosphorylation, we investigated the ability of two E. coli clinical isolates to activate platelets in plasma, in the presence or absence of specific receptors and signaling inhibitors. Aggregation assays with washed platelets supplemented with IgGs were performed to evaluate the requirement of this plasma component in activation. We found a critical role for the immune receptor FcγRIIA, αIIbβ3, and Src and Syk tyrosine kinases in platelet activation in response to E. coli. IgG and αIIbβ3 engagement was required for FcγRIIA activation. Moreover, feedback mediators adenosine 5’-diphosphate (ADP) and thromboxane A₂ (TxA₂) were essential for platelet aggregation. These findings suggest that human platelet responses to E. coli isolates are similar to those induced by Gram-positive organisms. Our observations support the existence of a central FcγRIIA-mediated pathway by which human platelets respond to both Gram-negative and Gram-positive bacteria.

A Metalloproteinase Mirolysin of Tannerella forsythia Inhibits All Pathways of the Complement System

Recent reports focusing on virulence factors of periodontal pathogens implicated proteinases as major determinants of remarkable pathogenicity of these species, with special emphasis on their capacity to modulate complement activity. In particular, bacteria-mediated cleavage of C5 and subsequent release of C5a seems to be an important phenomenon in the manipulation of the local inflammatory response in periodontitis. In this study, we present mirolysin, a novel metalloproteinase secreted by Tannerella forsythia, a well-recognized pathogen strongly associated with periodontitis. Mirolysin exhibited a strong effect on all complement pathways. It inhibited the classical and lectin complement pathways due to efficient degradation of mannose-binding lectin, ficolin-2, ficolin-3, and C4, whereas inhibition of the alternative pathway was caused by degradation of C5. This specificity toward complement largely resembled the activity of a previously characterized metalloproteinase of T. forsythia, karilysin. Interestingly, mirolysin released the biologically active C5a peptide in human plasma and induced migration of neutrophils. Importantly, we demonstrated that combination of mirolysin with karilysin, as well as a cysteine proteinase of another periodontal pathogen, Prevotella intermedia, resulted in a strong synergistic effect on complement. Furthermore, mutant strains of T. forsythia, devoid of either mirolysin or karilysin, showed diminished survival in human serum, providing further evidence for the synergistic inactivation of complement by these metalloproteinases. Taken together, our findings on interactions of mirolysin with complement significantly add to the understanding of immune evasion strategies of T. forsythia and expand the knowledge on molecular mechanisms driving pathogenic events in the infected periodontium.

Amplification of bacteria-induced platelet activation is triggered by FcγRIIA, integrin αIIbβ3, and platelet factor 4

Bacterial adhesion to platelets is mediated via a range of strain-specific bacterial surface proteins that bind to a variety of platelet receptors. It is unclear how these interactions lead to platelet activation. We demonstrate a critical role for the immune receptor FcγRIIA, αIIbβ3, and Src and Syk tyrosine kinases in platelet activation by Staphylococcus aureus, Streptococcus sanguinis, Streptococcus gordonii, Streptococcus oralis, and Streptococcus pneumoniae. FcγRIIA activation is dependent on immunoglobulin G (IgG) and αIIbβ3 engagement. Moreover, feedback agonists adenosine 5'-diphosphate and thromboxane A2 are mandatory for platelet aggregation. Additionally, platelet factor 4 (PF4) binds to bacteria and reduces the lag time for aggregation, and gray platelet syndrome α-granule-deficient platelets do not aggregate to 4 of 5 bacterial strains. We propose that FcγRIIA-mediated activation is a common response mechanism used against a wide range of bacteria, and that release of secondary mediators and PF4 serve as a positive feedback mechanism for activation through an IgG-dependent pathway.

Medical considerations relating to the oral health of older adults

This review paper was written in conjunction with the 2010 National Coalition Consensus Conference: Oral Health of Vulnerable Older Adults and Persons with Disabilities. It provides an overview of specific medical considerations involved with dental diagnosis and treatment of this "at risk population." The role of oral inflammation is referenced within the context of the oral/systemic paradigm (e.g., diabetes, cardiovascular disease/stroke, respiratory diseases, and cognition). Oral manifestations associated with multi-organ diseases, tobacco/alcohol use, and medications are additionally discussed. Finally, the paper encourages development of interdisciplinary approaches to positively influence health outcomes.

A metalloproteinase karilysin present in the majority of Tannerella forsythia isolates inhibits all pathways of the complement system

Tannerella forsythia is a poorly studied pathogen despite being one of the main causes of periodontitis, which is an inflammatory disease of the supporting structures of the teeth. We found that despite being recognized by all complement pathways, T. forsythia is resistant to killing by human complement, which is present at up to 70% of serum concentration in gingival crevicular fluid. Incubation of human serum with karilysin, a metalloproteinase of T. forsythia, resulted in a decrease in bactericidal activity of the serum. T. forsythia strains expressing karilysin at higher levels were more resistant than low-expressing strains. Furthermore, the low-expressing strain was significantly more opsonized with activated complement factor 3 and membrane attack complex from serum compared with the other strains. The high-expressing strain was more resistant to killing in human blood. The protective effect of karilysin against serum bactericidal activity was attributable to its ability to inhibit complement at several stages. The classical and lectin complement pathways were inhibited because of the efficient degradation of mannose-binding lectin, ficolin-2, ficolin-3, and C4 by karilysin, whereas inhibition of the terminal pathway was caused by degradation of C5. Interestingly, karilysin was able to release biologically active C5a peptide in human plasma and induce migration of neutrophils. Importantly, we detected the karilysin gene in >90% of gingival crevicular fluid samples containing T. forsythia obtained from patients with periodontitis. Taken together, the newly characterized karilysin appears to be an important virulence factor of T. forsythia and might have several important implications for immune evasion.

Streptococcus sanguinis-induced cytokine release from platelets

BACKGROUND

There is increasing evidence that both chronic and acute infections play a role in the development and progression of atherothrombotic disorders. One potential mechanism is the direct activation of platelets by bacteria. A wide range of bacterial species activate platelets through heterogeneous mechanisms. The oral micro-organism S. sanguinis stimulates platelet aggregation in vitro in a strain-dependent manner, although there are no reports of associated cytokine production.

OBJECTIVE

The aim of the present study was to determine whether platelet activation by S. sanguinis involved the release of pro-inflammatory and immune modulating factors, and whether activation was enhanced by epinephrine.

METHODS AND RESULTS

Four strains of S. sanguinis and one of S. gordonii stimulated the release of RANTES, PF4, sCD40L and PDGF-AB, whereas only one S. sanguinis strain caused the release of sCD62p. Epinephrine enhanced S. sanguinis-induced platelet aggregation and phosphorylation of phospholipase Cγ2 and Erk, but inhibited RANTES, PF4, sCD40L and PDGF-AB release. Wortmannin inhibited S. sanguinis-induced aggregation and release; however, only aggregation was partially reversed by epinephrine.

CONCLUSIONS

The present study demonstrates that platelets respond to S. sanguinis with both prothrombotic and pro-inflammatory/immune-modulating responses. Epinephrine, potentially released in response to infection and/or stress, can significantly enhance the prothrombotic response, thereby providing a putative link between bacteraemia and acute coronary events during stress. In contrast, epinephrine inhibited the pro-inflammatory/immune-modulating response by an undetermined mechanism.

Association between periodontal pathogens and risk of nonfatal myocardial infarction

BACKGROUND

The direct effect of periodontal pathogens on atherosclerotic plaque development has been suggested as a potential mechanism for the observed association between periodontal disease and coronary heart disease, but few studies have tested this theory.

OBJECTIVES

(i) To assess the association of periodontal pathogens in periodontal pockets with the risk of myocardial infarction (MI) and (ii) to assess whether an increase in the number of periodontal bacterial species increases the risk of MI.

METHODS

A total of 313 cases and 747 controls, consisting of Caucasian men and women from Western New York, aged 35 to 69 years, were recruited for this study. The presence of microorganisms was assessed by indirect immunofluorescence microscopy, using species-specific polyclonal and monoclonal serodiagnostic reagents. The presence of six periodontal pathogens, Porphyromonas gingivalis (Pg), Tannerella forsythensis (Tf), Prevotella intermedia (Pi), Campylobacter recta (Cr), Fusobacterium nucleatum (Fn), and Eubacterium saburreum (Es), and their co-occurrence (0-6) was compared with the odds of having myocardial infarction.

RESULTS

Univariate analyses revealed a higher percentage of the presence of each bacterium in cases compared to controls. In multivariate analyses, only Tf and Pi were statistically associated with an increase in the odds of having MI [Odds ratio OR=1.62; 95% CI (1.18-2.22); and 1.40; 95% (1.02-1.92), respectively] after adjusting for age, gender, education, cholesterol, high blood pressure, diabetes, and total pack-years of cigarette smoking. An increase in the number of different periodontal bacteria in pockets was also found to increase the odds of MI [adjusted OR=1.14; 95% CI (1.03-1.26)]. Participants who had three species or more of periodontal pathogens had about 2-fold increase in odds of having nonfatal MI than those who did not have any type of bacterial species [OR=2.01 (1.31-3.08)].

CONCLUSION

The presence of periodontal pathogens, specifically Tf or Pi, and an increase in total burden of periodontal pathogenic species were both associated with increased odds of having MI. However, further studies are needed to better assess any causal relationship, as well as the biological mechanisms underlying this association.

Carotid intima media thickness as a measure of cardiovascular disease burden in nigerian africans with hypertension and diabetes mellitus

As part of a larger study of cardiovascular risk factors in nonhypertensive type 2 diabetes patients, we subjected a cohort of diabetics to B mode ultrasonography of the carotid artery to measure the intima media thickness (IMT) and compared it with values in hypertensives and apparently normal controls matched reasonably for gender and age. All groups were comparable in terms of age and gender representation. The mean (SD) of carotid IMT right and left was 0.94 mm (0.12), 0.94 mm (0.16); 0.93 mm (0.21), 0.93 mm (0.15); 0.91 mm (0.17), 0.91 mm (0.13) for diabetic, hypertensive, and normal groups, respectively. There was a nonsignificant tendency to raised IMT for the disease groups from the normal ones. Diabetic and hypertensive Nigerians are equally burdened by cardiovascular disease risk factors. Apparently normal subjects have a reasonable degree of burden suggesting the need to evaluate them for other traditional and emerging risk factors.

Diabetes, periodontitis, and the subgingival microbiota

Both type 1 and type 2 diabetes have been associated with increased severity of periodontal disease for many years. More recently, the impact of periodontal disease on glycaemic control has been investigated. The role of the oral microbiota in this two-way relationship is at this stage unknown. Further studies, of a longitudinal nature and investigating a wider array of bacterial species, are required in order to conclusively determine if there is a difference in the oral microbiota of diabetics and non-diabetics and whether this difference accounts, on the one hand, for the increased severity of periodontal disease and on the other for the poorer glycaemic control seen in diabetics.

Roles of oral bacteria in cardiovascular diseases--from molecular mechanisms to clinical cases: Implication of periodontal diseases in development of systemic diseases

Periodontal diseases, some of the most common infectious diseases seen in humans, are characterized by gingival inflammation, as well as loss of connective tissue and bone from around the roots of the teeth, which leads to eventual tooth exfoliation. In the past decade, the association of periodontal diseases with the development of systemic diseases has received increasing attention. Although a number of studies have presented evidence of close relationships between periodontal and systemic diseases, the majority of findings are limited to epidemiological studies, while the etiological details remain unclear. Nevertheless, a variety of recent hypothesis driven investigations have compiled various results showing that periodontal infection and subsequent direct oral-hematogenous spread of bacteria are implicated in the development of various systemic diseases. Herein, we present current understanding in regard to the relationship between periodontal and systemic diseases, including cardiovascular diseases, preterm delivery of low birth weight, diabetes mellitus, respiratory diseases, and osteoporosis.