Increased levels of circulating endothelial progenitor cells in subjects with moderate to severe chronic periodontitis

Relationship between Carotid Intima-Media Thickness, Periodontal Disease, and Systemic Inflammation Biomarkers in an Adult Population

A positive relationship has been reported between advanced periodontitis and carotid intima-media thickness (cIMT) measurement. The aim of this study was to investigate this relationship with parameters for periodontitis, such as PISA and systemic inflammation biomarkers. An observational descriptive cross-sectional study was conducted. A blood sample was collected from 75 subjects to analyze glucose, total cholesterol, HDL, LDL, and cytokine values. Increased cIMT was found in 32% of the patients with fewer teeth. Patients with periodontitis had a larger periodontal inflamed surface area (PISA) (p = 0.000) and had a 1.42-times-higher risk of having increased cIMT values compared to periodontally healthy individuals, though without a statistically significant association. Higher values in the left cIMT, IL-8, and TNF-α were found in men than in women with significant differences. In the multivariate analysis involving cytokines, age continues to be linked to increased cIMT values. INF-γ showed a trend towards a protective effect; as the IMT-M decreases, there is an increase in the expression of INF-γ, and a higher proportion of subjects with elevated INF-γ concentrations demonstrated normal IMT-C. This study did not find a statistically significant association between cIMT and periodontal disease, but the risk of having increased cIMT is 1.42-times higher for individuals with periodontitis.

Periodontal inflammation is associated with increased circulating levels of endothelial progenitor cells: a retrospective cohort study in a high vascular risk population

Background

One of the main biological mechanisms behind the link between periodontitis and atherosclerotic vascular diseases is vascular endothelial dysfunction. Particularly, circulating endothelial progenitor cells (EPCs) have been considered a biomarker of altered vascular endothelial function.

Objectives

The aim of this study was to investigate relationship between periodontal inflammation and increased number of circulating EPCs.

Design

This is retrospective cohort study.

Methods

In this study, 85 elderly patients with a previous history of hypertension were followed up to 12 months. A baseline full-mouth periodontal assessment was carried out, and the amount of periodontal tissue inflamed per subject was calculated as a proxy of periodontal inflammation [periodontal inflamed surface area (PISA)]. The number of circulating EPCs (CD34+/CD133+/KDR+) was determined by flow cytometry from peripheral blood samples collected at baseline and 12 months.

Results

Mean concentrations of CD34+/CD133+/KDR+ progenitor cells were higher in periodontitis patients than in those without periodontitis at baseline [55.4, 95% confidence interval (CI) = 20.8 to 90.0 versus 27.2, 95% CI = 13.6 to 40.8, p = 0.008] and 12 months (114.6, 95% CI = 53.5 to 175.7 versus 19.1, 95% CI = 10.8 to 27.4, p = 0.003). A significant increase over the follow-up was noticed in the group of subjects with periodontitis (p = 0.049) but not in the nonperiodontitis group (p = 0.819). PISA was independently associated with CD34+/CD133+/KDR+ EPCs at baseline (B coefficient = 0.031, 95% CI = 0.005 to 0.058; p = 0.021). The relationship between PISA and CD34+/CD133+/KDR+ EPCs at 12 months was confounded by increased baseline body mass index (B coefficient = 0.064, 95% CI = -0.005 to 0.132; p = 0.066).

Conclusion

Periodontal inflammation is associated with high number of CD34+/CD133+/KDR+ EPCs, thus supporting a potential link between periodontitis and endothelial dysfunction.

Discovering genetic linkage between periodontitis and type 1 diabetes: A bioinformatics study

Background: Relationship between periodontitis (PD) and type 1 diabetes (T1D) has been reported, but the detailed pathogenesis requires further elucidation. This study aimed to reveal the genetic linkage between PD and T1D through bioinformatics analysis, thereby providing novel insights into scientific research and clinical treatment of the two diseases.

Methods: PD-related datasets (GSE10334, GSE16134, GSE23586) and T1D-related datasets(GSE162689)were downloaded from NCBI Gene Expression Omnibus (GEO). Following batch correction and merging of PD-related datasets as one cohort, differential expression analysis was performed (adjusted p-value <0.05 and ∣log2  fold change| > 0.5), and common differentially expressed genes (DEGs) between PD and T1D were extracted. Functional enrichment analysis was conducted via Metascape website. The protein-protein interaction (PPI) network of common DEGs was generated in The Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database. Hub genes were selected by Cytoscape software and validated by receiver operating characteristic (ROC) curve analysis.

Results: 59 common DEGs of PD and T1D were identified. Among these DEGs, 23 genes were commonly upregulated, and 36 genes were commonly downregulated in both PD- and T1D-related cohorts. Functional enrichment analysis indicated that common DEGs were mainly enriched in tube morphogenesis, supramolecular fiber organization, 9 + 0 non-motile cilium, plasma membrane bounded cell projection assembly, glomerulus development, enzyme-linked receptor protein signaling pathway, endochondral bone morphogenesis, positive regulation of kinase activity, cell projection membrane and regulation of lipid metabolic process. After PPI construction and modules selection, 6 hub genes (CD34, EGR1, BBS7, FMOD, IGF2, TXN) were screened out and expected to be critical in linking PD and T1D. ROC analysis showed that the AUC values of hub genes were all greater than 70% in PD-related cohort and greater than 60% in T1D-related datasets.

Conclusion: Shared molecular mechanisms between PD and T1D were revealed in this study, and 6 hub genes were identified as potential targets in treating PD and T1D.

Meta-analysis of the association between periodontal disease, periodontal treatment and carotid intima-media thickness

Periodontal disease is a major threat to oral health and would further contribute to systemic diseases without timely control. We aimed to evaluate the relation between periodontal disease, periodontal treatment and carotid intima-media thickness (CIMT) based on available epidemiological and clinical evidence. PubMed and Scopus were searched for relevant studies through May 2021. Observational studies reporting risk estimates with 95% confidence intervals (95% CIs) for the association between periodontal disease (including periodontitis and gingivitis) and risk of increased CIMT (defined as CIMT value that exceeded the cut-off value of clinical and prognostic significance), as well as interventional studies providing mean values with standard deviations of CIMT before and after periodontal intervention, were included. Random-effect models for meta-analysis were used to calculate the summary effect estimates with 95% CIs. A total of 406 citations were retrieved from electronic databases and 45 full-text articles were screened, leaving 11 articles using ultrasound to measure CIMT with 8744 participants included. Pooled results of seven cross-sectional studies involving 8558 participants indicated that compared to those without periodontitis, patients with periodontitis and those with severe periodontitis had an odds ratio of 1.42 (95% CI: 1.16, 1.75) and 1.70 (95% CI: 1.24, 2.33) for increased CIMT, respectively. Although publication bias was detected in these results, odds ratios corrected by the trim-and-fill method were still statistically significant. Results of four non-randomized controlled trials with 186 patients suggested that periodontal intervention may help reduce CIMT in patients with periodontal disease in the short term. Periodontitis, especially severe periodontitis, was significantly associated with the risk of increased CIMT. Periodontal intervention might help slow the progression of carotid intima-media thickening in patients with periodontal disease in the short term.

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.

Treatment of periodontitis for glycaemic control in people with diabetes mellitus

BACKGROUND

Glycaemic control is a key component in diabetes mellitus (diabetes) management. Periodontitis is the inflammation and destruction of the underlying supporting tissues of the teeth. Some studies have suggested a bidirectional relationship between glycaemic control and periodontitis.  Treatment for periodontitis involves subgingival instrumentation, which is the professional removal of plaque, calculus, and debris from below the gumline using hand or ultrasonic instruments. This is known variously as scaling and root planing, mechanical debridement, or non-surgical periodontal treatment. Subgingival instrumentation is sometimes accompanied by local or systemic antimicrobials, and occasionally by surgical intervention to cut away gum tissue when periodontitis is severe. This review is part one of an update of a review published in 2010 and first updated in 2015, and evaluates periodontal treatment versus no intervention or usual care.  OBJECTIVES: To investigate the effects of periodontal treatment on glycaemic control in people with diabetes mellitus and periodontitis.

SEARCH METHODS

An information specialist searched six bibliographic databases up to 7 September 2021 and additional search methods were used to identify published, unpublished, and ongoing studies.  SELECTION CRITERIA: We searched for randomised controlled trials (RCTs) of people with type 1 or type 2 diabetes mellitus and a diagnosis of periodontitis that compared subgingival instrumentation (sometimes with surgical treatment or adjunctive antimicrobial therapy or both) to no active intervention or 'usual care' (oral hygiene instruction, education or support interventions, and/or supragingival scaling (also known as PMPR, professional mechanical plaque removal)). To be included, the RCTs had to have lasted at least 3 months and have measured HbA1c (glycated haemoglobin).

DATA COLLECTION AND ANALYSIS

At least two review authors independently examined the titles and abstracts retrieved by the search, selected the included trials, extracted data from included trials, and assessed included trials for risk of bias. Where necessary and possible, we attempted to contact study authors. Our primary outcome was blood glucose levels measured as glycated (glycosylated) haemoglobin assay (HbA1c), which can be reported as a percentage of total haemoglobin or as millimoles per mole (mmol/mol). Our secondary outcomes included adverse effects, periodontal indices (bleeding on probing, clinical attachment level, gingival index, plaque index, and probing pocket depth), quality of life, cost implications, and diabetic complications.

MAIN RESULTS

We included 35 studies, which randomised 3249 participants to periodontal treatment or control. All studies used a parallel-RCT design and followed up participants for between 3 and 12 months. The studies focused on people with type 2 diabetes, other than one study that included participants with type 1 or type 2 diabetes. Most studies were mixed in terms of whether metabolic control of participants at baseline was good, fair, or poor. Most studies were carried out in secondary care.  We assessed two studies as being at low risk of bias, 14 studies at high risk of bias, and the risk of bias in 19 studies was unclear. We undertook a sensitivity analysis for our primary outcome based on studies at low risk of bias and this supported the main findings. Moderate-certainty evidence from 30 studies (2443 analysed participants) showed an absolute reduction in HbA1c of 0.43% (4.7 mmol/mol) 3 to 4 months after treatment of periodontitis (95% confidence interval (CI) -0.59% to -0.28%; -6.4 mmol/mol to -3.0 mmol/mol). Similarly, after 6 months, we found an absolute reduction in HbA1c of 0.30% (3.3 mmol/mol) (95% CI -0.52% to -0.08%; -5.7 mmol/mol to -0.9 mmol/mol; 12 studies, 1457 participants), and after 12 months, an absolute reduction of 0.50% (5.4 mmol/mol) (95% CI -0.55% to -0.45%; -6.0 mmol/mol to -4.9 mmol/mol; 1 study, 264 participants). Studies that measured adverse effects generally reported that no or only mild harms occurred, and any serious adverse events were similar in intervention and control arms. However, adverse effects of periodontal treatments were not evaluated in most studies.

AUTHORS' CONCLUSIONS

Our 2022 update of this review has doubled the number of included studies and participants, which has led to a change in our conclusions about the primary outcome of glycaemic control and in our level of certainty in this conclusion. We now have moderate-certainty evidence that periodontal treatment using subgingival instrumentation improves glycaemic control in people with both periodontitis and diabetes by a clinically significant amount when compared to no treatment or usual care. Further trials evaluating periodontal treatment versus no treatment/usual care are unlikely to change the overall conclusion reached in this review.

A randomized controlled trial of the effects of non-surgical periodontal therapy on cardiac function assessed by echocardiography in type 2 diabetic patients

BACKGROUND

Periodontitis significantly increases the risk of diabetic complications. This clinical trial investigated the effects of periodontal therapy on cardiac function in patients with type 2 diabetes mellitus (T2DM) and periodontitis.

MATERIALS AND METHODS

Fifty-eight subjects with T2DM and periodontitis were randomly allocated to Treatment Group (n = 29) receiving non-surgical periodontal therapy, and Control Group (n = 29) having only oral hygiene instructions with delayed periodontal treatment until completion of this 6-month study. The left ventricle (LV) diastolic function was assessed by echocardiography with the tissue Doppler imaging index (E/e' ratio); and LV hypertrophy was evaluated by LV mass index (LVMI). Blood samples were collected for biochemical analysis.

RESULTS

The intention-to-treat analysis showed that periodontal treatment significantly reduced the E/e' ratio by 1.66 (95% CI: -2.64 to -0.68, p < .01), along with marked improvement of periodontal conditions (p < .05). LVMI was not altered at the 6-month follow-up. The serum levels of N-terminal pro-B type natriuretic peptide (NT-proBNP) as a cardiac stress biomarker, C-reactive protein and interleukin-6 decreased numerically without reaching statistical significance.

CONCLUSION

The present study provides the first evidence that non-surgical periodontal therapy may improve cardiac diastolic function in type 2 diabetic patients with periodontitis.

Periodontitis and Tooth Loss Have Negative Systemic Impact on Circulating Progenitor Cell Levels: A Clinical Study

The aim of the present study was to investigate the association and impact of periodontitis and tooth loss on a subtype of endothelial progenitor cell (EPC) levels (CD133+/KDR+). Furthermore, the objective was to determine if the periodontal status influenced CD133+/KDR+ levels. In all, 88 patients with periodontitis and 79 healthy controls (HCs) were enrolled in the study. Enrolled patients were examined and characterized by clinical and blood sample analysis. Spearman's correlation test was applied in order to assess the interdependence between CD133+/KDR+ levels and all periodontal parameters. In order to estimate a statistically significant trend (p-trend) for ordered CD133++/KDR+ quartiles, the Jonckheere-Terpstra test was applied for all variables. Patients in the periodontitis group presented significantly lower CD133+/KDR+ levels (66.4 (45.5-269.6 cells/µL)) compared to the HC group (76.7 (24.3-313.2 cells/µL), p < 0.001). Lower CD133+/KDR+ levels negatively correlated with C-reactive protein (CRP), with the number of teeth, and with all periodontal parameters (p < 0.001). Moreover, there was a proportional increase in CD133+/KDR+ levels with a progressive increase in number of teeth (p-trend < 0.001), while there was a proportional decrease in CD133+/KDR+ levels with a proportional increase in clinical attachment level (CAL, p-trend = 0.003), probing depth (PD, p-trend = 0.007), and bleeding sites (bleeding on probing (BOP), p-trend < 0.001) as an extent measure of periodontitis. This study demonstrated that patients with periodontitis presented significantly lower CD133+/KDR+ levels compared to HCs. Moreover, all patients presented an increase in the CD133+/KDR+ EPC levels with an extended level of periodontitis and tooth loss.

Periodontal disease as a potential factor of migraine chronification

Migraine is a hereditary constitutional base disorder, which is characterized by recurrent episodes of headache pulsatile characteristics associated with photophobia/phonophobia, nausea and/or vomiting. The main complication in migraine is the chronicity of the process, now recognized as a chronic migraine. Although pathogenic mechanisms that may influence the pathophysiology of migraine and its possible chronicity are not fully understood, previous studies have shown in patients with migraine molecular alterations of systemic inflammation, neurogenic inflammation, endothelial dysfunction, innate immunity, dysfunction of matrix proteases and blood-brain barrier. Periodontal disease is an inflammatory lesion caused by bacteria. After the bacterial infection begins, an immune response that will be responsible for individual susceptibility appears. More advanced forms of periodontitis have demonstrated molecular alterations of inflammation, endothelial dysfunction, dysfunction of matrix proteases and innate immunity, similar to those observed in migraine. Furthermore, the main molecular mediators of neurogenic inflammation related to activation of the trigeminovascular system, which are characteristic of migraine, are overexpressed in gingival crevicular fluid and mucosa in patients with periodontal disease. Hypertension, hypercholesterolemia, insulin resistance, stroke or coronary artery disease are comorbidities that periodontal disease and migraine could share. Therefore, several mechanisms and hypotheses could explain the possible association between both diseases. However, epidemiological and molecular studies will be necessary to provide a better understanding of this potential association, which could be implicated in the chronification of migraine.

Evidence that periodontal treatment improves biomarkers and CVD outcomes

AIM

The aim of this review was to critically appraise the evidence on the impact of periodontal treatment of cardiovascular diseases (CVDs) biomarkers and outcomes.

METHODS

A systematic search was performed in Cinhal, Cochrane, Embase and Medline for relevant articles up to July 2012. Duplicate screening and reference hand searching were performed. Data were then summarized and evidence graded in tables.

RESULTS

The search resulted in: (a) no evidence on the effects of periodontal therapy on subclinical atherosclerosis, serum levels of CD40 ligand, serum amyloid A and monocyte chemoattractant protein-1, (b) limited evidence on the effects of periodontal therapy on arterial blood pressure, leucocyte counts, fibrinogen, tissue necrosis factor-α, sE-selectin, von Willebrand factors, d-dimers, matrix metalloproteinases, oxidative stress and CVD events, and (c) moderate evidence suggesting a negligible effect of periodontal therapy in reducing interleukin-6 and lipids levels, whilst a positive effect in reducing serum C-reactive protein levels and improving endothelial function.

CONCLUSIONS

Periodontal therapy triggers a short-term inflammatory response followed by (a) a progressive and consistent reduction of systemic inflammation and (b) an improvement in endothelial function. There is however limited evidence that these acute and chronic changes will either increase or reduce CVD burden of individuals suffering from periodontitis in the long term.

Evidence that periodontal treatment improves biomarkers and CVD outcomes

AIM

The aim of this review was to critically appraise the evidence on the impact of periodontal treatment of cardiovascular diseases (CVDs) biomarkers and outcomes.

METHODS

A systematic search was performed in Cinhal, Cochrane, Embase and Medline for relevant articles up to July 2012. Duplicate screening and reference hand searching were performed. Data were then summarized and evidence graded in tables.

RESULTS

The search resulted in: (a) no evidence on the effects of periodontal therapy on subclinical atherosclerosis, serum levels of CD40 ligand, serum amyloid A and monocyte chemoattractant protein-1, (b) limited evidence on the effects of periodontal therapy on arterial blood pressure, leucocyte counts, fibrinogen, tissue necrosis factor-a, sE-selectin, von Willebrand factors, d-dimers, matrix metalloproteinases, oxidative stress and CVD events, and (c) moderate evidence suggesting a negligible effect of periodontal therapy in reducing interleukin-6 and lipids levels, whilst a positive effect in reducing serum C-reactive protein levels and improving endothelial function.

CONCLUSIONS

Periodontal therapy triggers a short-term inflammatory response followed by (a) a progressive and consistent reduction of systemic inflammation and (b) an improvement in endothelial function. There is however limited evidence that these acute and chronic changes will either increase or reduce CVD burden of individuals suffering from periodontitis in the long term.

Circulating endothelial progenitor cells in periodontitis

BACKGROUND

Several biologically plausible mechanisms have been proposed to mediate the association between periodontitis and atherosclerotic vascular disease (AVD), including adverse effects on vascular endothelial function. Circulating endothelial progenitor cells (cEPCs) are known to contribute to vascular repair, but limited data are available regarding the relationship between cEPC levels and periodontitis. The aims of this cross-sectional study are to investigate the levels of hemangioblastic and monocytic cEPCs in patients with periodontitis and periodontally healthy controls and to associate cEPC levels with the extent and severity of periodontitis.

METHODS

A total of 112 individuals (56 patients with periodontitis and 56 periodontally healthy controls, aged 26 to 65 years; mean age: 43 years) were enrolled. All participants underwent a full-mouth periodontal examination and provided a blood sample. Hemangioblastic cEPCs were assessed using flow cytometry, and monocytic cEPCs were identified using immunohistochemistry in cultured peripheral blood mononuclear cells. cEPC levels were analyzed in the entire sample, as well as in a subset of 50 pairs of patients with periodontitis/periodontally healthy controls, matched with respect to age, sex, and menstrual cycle.

RESULTS

Levels of hemangioblastic cEPCs were approximately 2.3-fold higher in patients with periodontitis than periodontally healthy controls, after adjustments for age, sex, physical activity, systolic blood pressure, and body mass index (P = 0.001). A non-significant trend for higher levels of monocytic cEPCs in periodontitis was also observed. The levels of hemangioblastic cEPCs were positively associated with the extent of bleeding on probing, probing depth, and clinical attachment loss. Hemangioblastic and monocytic cEPC levels were not correlated (Spearman correlation coefficient 0.03, P = 0.77), suggesting that they represent independent populations of progenitor cells.

CONCLUSION

These findings further support the notion that oral infections have extraoral effects and document that periodontitis is associated with a mobilization of EPCs from the bone marrow, apparently in response to systemic inflammation and endothelial injury.

Multiple tooth loss is associated with vascular cognitive impairment in subjects with acute ischemic stroke

BACKGROUND AND OBJECTIVE

Emerging evidence shows that tooth loss is associated with cognitive impairment and dementia. Vascular cognitive impairment (VCI) is a common consequence of ischemic stroke. This study investigated the association of tooth loss with VCI in patients with acute stroke.

MATERIAL AND METHODS

A total of 161 subjects with acute ischemic stroke were recruited. Within 1 wk after admission, fasting blood tests were undertaken and the number of teeth present was recorded. VCI was evaluated with the Montreal Cognitive Assessment (MoCA).

RESULTS

The patients with loss of ≥ 8 teeth exhibited significantly lower MoCA values as compared to those with loss of ≤ 7 teeth (13.2 ± 6.6 vs. 17.3 ± 6.0, p < 0.001). Multivariate logistic regression analysis showed that loss of ≥ 8 teeth (OR = 3.1, 95% CI: 1.2-7.9, p = 0.02) and stroke history (OR = 3.8, 95% CI: 1.1-14.1, p = 0.04) were significantly associated with VCI (MoCA score ≤ 20.0).

CONCLUSION

Within the limitations of this study, the current findings provide the first evidence that multiple tooth loss is independently associated with VCI in patients with acute ischemic stroke.

Expression of VEGF in Periodontal Tissues of Type II Diabetes Mellitus Patients with Chronic Periodontitis -an Immunohistochemical Study

BACKGROUND

Vascular endothelial growth factor (VEGF) induces proliferation of endothelial cells, stimulates angiogenesis, and increases vascular permeability, but information about its role in periodontal diseases is limited. The aim of this study is to determine the association between VEGF expression in healthy and periodontally diseased tissues of healthy and diabetic patients.

MATERIALS AND METHODS

Seventeen systemically healthy and 17 Type 2 diabetic patients (DM), all diagnosed with periodontitis were enrolled into the study. Gingival samples were collected from both periodontal and healthy sites in all patients. Each patient served as his/her own control samples were subjected to immunohistochemical analysis.

RESULTS

The diseased sites of diabetic subjects expressed higher level of VEGF when compared to diseased sites of non diabetic subjects with chronic periodontitis, VEGF was observed in healthy periodontal tissues of both diabetic and systemically healthy people with periodontitis and VEGF was intensely present in monocytes and macrophages.

CONCLUSION

The increased expression of VEGF in diseased sites of diabetic patients suggests that diabetes mellitus might have direct influence over VEGF expression.

Association between periodontal disease and its treatment, flow-mediated dilatation and carotid intima-media thickness: a systematic review and meta-analysis

OBJECTIVE

This meta-analysis sought to investigate the association between carotid intima-media thickness (c-IMT), flow-mediated dilation (FMD) and periodontitis (PD) and to assess the effect of periodontal treatment on c-IMT and FMD.

METHODS

Electronic database searching, hand searching of bibliographic references of included papers, related reviews, and journals in relation to oral, cardiovascular and ultrasound imaging field was carried out. Random effects meta-analyses were performed to investigate the association of co-existence of increased c-IMT, impaired FMD and PD with potential changes in these variables following periodontal intervention.

RESULTS

2009 citations and 101 full text articles were screened, with 35 meeting the review inclusion criteria of which 22 suitable for quantitative analysis. Meta-analysis demonstrated that the diagnosis of PD was associated with a mean increase in c-IMT of 0.08 mm (95% C.I. = 0.07-0.09) and a mean difference in FMD of 5.1% compared to controls (95% C.I. = 2.08-8.11%). A meta-analysis of the effects of periodontal treatment on FMD showed a mean improvement of 6.64% between test and control (95% C.I. = 2.83-10.44%).

CONCLUSIONS

This review demonstrated an association between increased c-IMT, impaired FMD and PD. Data from intervention studies suggested a beneficial effect of periodontal treatment on FMD indicating an improvement in endothelial function. The findings support investigation of periodontitis treatment on cardiovascular outcomes.

The effect of periodontal therapy on C-reactive protein, endothelial function, lipids and proinflammatory biomarkers in patients with stable coronary artery disease: study protocol for a randomized controlled trial

BACKGROUND

Scarce information exists regarding the preventive effect of periodontal treatment in the recurrence of cardiovascular events. Prevention may be achieved by targeting risk factors for recurrent coronary artery disease (CAD) in patients with previous history of cardiovascular events. The aim of this trial is to compare the effect of two periodontal treatment approaches on levels of C-reactive protein, lipids, flow-mediated dilation and serum concentrations of proinflammatory and endothelial markers in stable CAD patients with periodontitis over a period of 12 months.

METHODS/DESIGN

This is a randomized, parallel design, examiner blinded, controlled clinical trial. Individuals from both genders, 35 years of age and older, with concomitant diagnosis of CAD and periodontitis will be included. CAD will be defined as the occurrence of at least one of the following events 6 months prior to entering the trial: documented history of myocardial infarction; surgical or percutaneous myocardial revascularization and lesion >50% in at least one coronary artery assessed by angiography; presence of angina and positive noninvasive testing of ischemia. Diagnosis of periodontitis will be defined using the CDC-AAP case definition (≥2 interproximal sites with clinical attachment loss ≥6 mm and ≥1 interproximal site with probing depth ≥5 mm). Individuals will have to present at least ten teeth present to be included. One hundred individuals will be allocated to test (intensive periodontal treatment comprised by scaling and root planing) or control (community periodontal treatment consisting of one session of supragingival plaque removal only) treatment groups. Full-mouth six sites per tooth periodontal examinations and subgingival biofilm samples will be conducted at baseline, 3, 6 and 12 months after treatment. The primary outcome of this study will be C-reactive protein changes over time. Secondary outcomes include levels of total cholesterol, LDL-C, HDL-C, triglycerides, IL-1β, IL-6, TNFα, fibrinogen, ICAM-1, VCAM-1 and E-selectin. These outcomes will be assessed at all time points over 12 months. Flow-mediated dilation will be assessed at baseline, 1, 3 and 6 months after periodontal therapy.

DISCUSSION

This trial will provide new evidence regarding the effect of periodontal treatment on risk markers for recurrence of cardiovascular events in stable coronary artery disease patients.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier, NCT01609725.

Mobilization of endothelial progenitors by recurrent bacteremias with a periodontal pathogen

Background

Periodontal infections are independent risk factors for atherosclerosis. However, the exact mechanisms underlying this link are yet unclear. Here, we evaluate the in vivo effects of bacteremia with a periodontal pathogen on endothelial progenitors, bone marrow-derived cells capable of endothelial regeneration, and delineate the critical pathways for these effects.

Methods

12-week old C57bl6 wildtype or toll-like receptor (TLR)-2 deficient mice were repeatedly intravenously challenged with 10⁹ live P. gingivalis 381 or vehicle. Numbers of Sca1+/flk1+ progenitors, circulating angiogenic cells, CFU-Hill, and late-outgrowth EPC were measured by FACS/culture. Endothelial function was assessed using isolated organ baths, reendothelization was measured in a carotid injury model. RANKL/osteoprotegerin levels were assessed by ELISA/qPCR.

Results

In wildtype mice challenged with intravenous P.gingivalis, numbers of Sca1+/flk1+ progenitors, CAC, CFU-Hill, and late-outgrowth EPC were strongly increased in peripheral circulation and spleen, whereas Sca1+/flk1+ progenitor numbers in bone marrow decreased. Circulating EPCs were functional, as indicated by improved endothelial function and improved reendothelization in infected mice. The osteoprotegerin/RANKL ratio was increased after P. gingivalis challenge in the bone marrow niche of wildtype mice and late-outgrowth EPC in vitro. Conversely, in mice deficient in TLR2, no increase in progenitor mobilization or osteoprotegerin/RANKL ratio was detected.

Conclusion

Recurrent transient bacteremias, a feature of periodontitis, increase peripheral EPC counts and decrease EPC pools in the bone marrow, thereby possibly reducing overall endothelial regeneration capacity, conceivably explaining pro-atherogenic properties of periodontal infections. These effects are seemingly mediated by toll-like receptor (TLR)-2.

The level of circulating endothelial progenitor cells may be associated with the occurrence and recurrence of chronic subdural hematoma

OBJECTIVES

The onset of chronic subdural hematoma may be associated with direct or indirect minor injuries to the head or a poorly repaired vascular injury. Endothelial progenitor cells happen to be one of the key factors involved in hemostasis and vascular repair. This study was designed to observe the levels of endothelial progenitor cells, white blood cells, platelets, and other indicators in the peripheral blood of patients diagnosed with chronic subdural hematoma to determine the possible relationship between the endothelial progenitor cells and the occurrence, development, and outcomes of chronic subdural hematoma.

METHOD

We enrolled 30 patients with diagnosed chronic subdural hematoma by computer tomography scanning and operating procedure at Tianjin Medical University General Hospital from July 2009 to July 2011. Meanwhile, we collected 30 cases of peripheral blood samples from healthy volunteers over the age of 50. Approximately 2 ml of blood was taken from veins of the elbow to test the peripheral blood routine and coagulation function. The content of endothelial progenitor cells in peripheral blood mononuclear cells was determined by flow cytometry.

RESULTS

The level of endothelial progenitor cells in peripheral blood was significantly lower in preoperational patients with chronic subdural hematomas than in controls. There were no significant differences between the two groups regarding the blood routine and coagulation function. However, the levels of circulating endothelial progenitor cells were significantly different between the recurrent group and the non-recurrent group.

CONCLUSIONS

The level of circulating endothelial progenitor cells in chronic subdural hematoma patients was significantly lower than the level in healthy controls. Meanwhile, the level of endothelial progenitor cells in recurrent patients was significantly lower than the level in patients without recurrence. Endothelial progenitor cells may be related to the occurrence and recurrence of chronic subdural hematoma.

Periodontal therapy decreases serum levels of adipocyte fatty acid-binding protein in systemically healthy subjects: a pilot clinical trial

BACKGROUND AND OBJECTIVE

Adipocyte fatty acid-binding protein (A-FABP) is expressed in adipocytes, macrophages and microvascular endothelial cells, and it plays a central role in inflammation, atherosclerosis and metabolic responses. This pilot study investigated the effect of nonsurgical periodontal therapy on the serum levels of A-FABP in subjects with chronic periodontitis.

MATERIAL AND METHODS

A pilot clinical trial was conducted in 24 otherwise healthy Chinese subjects with moderate to severe chronic periodontitis. The treatment group (n = 12) received nonsurgical periodontal therapy immediately, whereas in the control group (n = 12) the treatment was delayed for 3 months. The serum levels of A-FABP were measured by ELISAs. Other inflammatory and endothelial biomarkers and periodontal conditions were evaluated at baseline and at the 3-month follow-up appointment.

RESULTS

A-FABP levels decreased significantly in the treatment group compared with the control group (treatment effect: -1.7 ng/mL; 95% confidence interval: -2.8 to -0.6; p = 0.003). The treatment also significantly improved periodontal conditions but had no significant effect on other biomarkers. In the multivariable regression model, the change in the percentage of sites with detectable plaque was significantly associated with the change in the level of A-FABP (beta: 0.04, 95% confidence interval: 0.01-0.06, p = 0.004).

CONCLUSION

Within the limitations of this pilot study, the current findings suggest that treatment of periodontitis may significantly decrease the serum levels of A-FABP. Further longitudinal study with a large sample size is warranted to confirm this finding and elaborate the relevant clinical implications.

Role of high endothelial postcapillary venules and selected adhesion molecules in periodontal diseases: a review

Periodontitis is accompanied by the proliferation of small blood vessels in the gingival lamina propria. Specialized postcapillary venules, termed periodontal high endothelial-like venules, are also present, and demonstrate morphological and functional traits similar to those of high endothelial venules (HEVs) in lymphatic organs. The suggested role of HEVs in the pathogenesis of chronic periodontitis involves participation in leukocyte transendothelial migration and therefore proinflammatory effects appear. Recent observations suggest that chronic periodontitis is an independent risk factor for systemic vascular disease and may result in stimulation of the synthesis of acute phase protein by cytokines released by periodontal high endothelial cells (HECs). However, tissue expression of HEV-linked adhesion molecules has not been evaluated in the gingiva of patients with chronic periodontitis. This is significant in relation to potential therapy targeting expression of the adhesion molecules. In this review, current knowledge of HEV structure and the related expression of four surface adhesion molecules of HECs [CD34, platelet endothelial cell adhesion molecule 1, endoglin and intercellular adhesion molecule 1 (ICAM-1)], involved in the key steps of the adhesion cascade in periodontal diseases, are discussed. Most studies on the expression of adhesion molecules in the development and progression of periodontal diseases pertain to ICAM-1 (CD54). Studies by the authors demonstrated quantitatively similar expression of three of four selected surface markers in gingival HEVs of patients with chronic periodontitis and in HEVs of reactive lymph nodes, confirming morphological and functional similarity of HEVs in pathologically altered tissues with those in lymphoid tissues.

Novel Endothelial Biomarkers: Implications for Periodontal Disease and CVD

Endothelial cells are actively involved in various aspects of vascular biology and different stages of atherosclerosis. Endothelial function is increasingly used as an important outcome measure in cardiovascular research. Endothelial progenitor cells (EPCs) are closely linked to endothelial function, and their biomarkers have received much attention. EPCs may not only serve as a pool of progenitor cells and possess the capacity to repair the damaged vasculature, but also act as potent effectors in systemic inflammation, suggesting that EPCs may play a critical role in maintaining endothelial function and the progression of cardiovascular disease (CVD). Emerging evidence shows an association of periodontal infections (gingivitis and periodontitis) with endothelial dysfunction, while the relevant mechanisms remain unknown. Our recent finding of the association of periodontitis with EPCs warrants their utilization as additional biomarkers in future studies on periodontal medicine. This review starts with a brief account on the current understanding of the nature of periodontal infections and their link with systemic inflammation and endothelial dysfunction. The paper also provides an update on endothelial biology and function as well as the novel biomarkers of EPCs and concludes with clinical studies on periodontal diseases and CVD.

Effect of periodontal treatment on circulating CD34(+) cells and peripheral vascular endothelial function: a randomized controlled trial

AIM

periodontal disease is associated with endothelial dysfunction and increased circulating progenitor cell (CPC) count. This study sought to investigate the effect of periodontal treatment on CPC count and vascular endothelial function.

MATERIALS AND METHODS

a single-blind, randomized controlled trial was conducted in 50 otherwise healthy subjects with moderate-to-severe chronic periodontitis. They were randomly assigned into Treatment group (n=25), in whom periodontal treatment was conducted immediately, and Control group (n=25), in whom periodontal treatment was postponed until the completion of this 3-month study. CPCs and peripheral endothelial function were evaluated at baseline and 3-month follow-up using flow cytometry and peripheral arterial tonometry, respectively.

RESULTS

based on the intention-to-treat analysis, periodontal treatment exhibited neutral effects on endothelial function [treatment effect: 0.03, 95% confidence interval (CI): -0.29 to 0.35, p=0.85]. However, circulating CD34(+) cells count significantly decreased in the Treatment group compared with the controls (treatment effect: -29.85 cells/μl, 95% CI: -52.62 to -7.08, p=0.011). The reduction of circulating CD34(+) count was positively correlated with the decrease in sites% with bleeding on probing or periodontal pockets 4 mm.

CONCLUSIONS

this study suggests that treatment of periodontitis has neutral effects on peripheral endothelial function but significantly decreases circulating CD34(+) cell count.

Periodontal disease as a risk marker in coronary heart disease and chronic kidney disease

PURPOSE OF REVIEW

More than half a million Americans die each year from coronary heart disease (CHD), 26 million suffer from chronic kidney disease (CKD), and a large proportion have periodontal disease, a chronic infection of the tissues surrounding teeth. Chronic inflammation contributes to CHD and CKD occurrence and progression, and periodontal disease contributes to the cumulated chronic systemic inflammatory burden. This review examines recent evidence regarding the role of periodontal disease in CHD and CKD.

RECENT FINDINGS

Periodontal pathogens cause both local infection and bacteremia, eliciting local and systemic inflammatory responses. Periodontal disease is associated with the systemic inflammatory reactant C-reactive protein (CRP), a major risk factor for both CHD and CKD. Nonsurgical periodontal disease treatment is shown to improve periodontal health, endothelial function, levels of CRP, and other inflammatory markers. Evidence for the association of periodontal disease with CKD consists of a small body of literature represented mainly by cross-sectional studies. No definitive randomized controlled trials exist with either CHD or CKD as primary endpoints.

SUMMARY

Recent evidence links periodontal disease with CHD and CKD. Adding oral health self-care and referral for professional periodontal assessment and therapy to the repertoire of medical care recommendations is prudent to improve patients' oral health and possibly reduce CHD and CKD risk.

Human gingiva is another site of C-reactive protein formation

OBJECTIVES

C-reactive protein (CRP) is primarily synthesized in the liver. It is hypothesized that human gingiva per se may produce CRP and its expression could be associated with IL-6. This study elucidated the CRP expression profile in human gingiva and its possible association with IL-6.

MATERIALS AND METHODS

Ninety-four gingival biopsies were collected from 44 subjects with chronic periodontitis and 18 periodontally healthy subjects. CRP protein was detected by immunohistochemistry and Western blotting, while CRP and IL-6 mRNAs were examined by reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time PCR. CRP protein expression in the reconstituted human gingival epithelia (RHGE) was examined by the particle-enhanced immunoturbidimetric assay and Western blotting.

RESULTS

CRP protein was detected in gingival tissues from patients and healthy subjects by immunohistochemistry and confirmed by Western blotting. Its expression pattern and level at 16 pairs of periodontal pocket tissues and the adjacent clinically healthy tissues from 16 patients were significantly interrelated (r(s)=0.693, p<0.01). CRP mRNA expression was strongly correlated with IL-6 (r=0.694, p<0.001). Both CRP protein and mRNA were detected in the RHGE.

CONCLUSIONS

The present study shows for the first time that human gingiva is able to produce CRP in situ that may be associated with IL-6 activity.

Masticatory dysfunction is associated with worse functional ability: a population-based study

AIM

Because of the ageing of populations, disability has become an emergent problem from the clinical, social, and economic perspectives. Nevertheless, the determinants of disability in older subjects are still unclear. We assessed the association between self-assessed masticatory dysfunction (MD) and functional ability in older subjects.

MATERIALS AND METHODS

We analysed data of all 350 subjects aged 75+ living in Tuscania (Italy). Functional ability was estimated using the Katz' activities of daily living (ADLs), and the Lawton and Brody instrumental activities of daily living (IADLs) scales.

RESULTS

MD was reported by 145 (41%) participants. Disability in the ADLs and IADLs was found in 37 (25%) and 53 (37%) of participants with MD, respectively, but only in 11 (5%) and 30 (15%) of the other participants (p<0.001). MD was associated with disability in the ADLs [odds ratio (OR)=2.40, 95% confidence interval (CI)=1.05-5.51], and IADLs (OR=2.77, 95% CI=1.07-7.16) in logistic regression, after adjusting. The association of MD with disability was stronger among subjects aged 80+.

CONCLUSIONS

MD is independently associated with disability in community-dwelling elderly. Further studies are needed to evaluate the impact of early detection and correction of MD on the preservation of functional status in older populations.