Correlation between the severity of periodontitis and coronary artery stenosis in a Chinese population

Potential biomarkers of acute myocardial infarction based on the composition of the blood microbiome

BACKGROUND

It is difficult to distinguish between acute myocardial infarction (AMI) and unstable angina (UA) due to their similar clinical features. In recent years, studies have shown that microbiomes have great potential in distinguishing diseases. The purpose of this study is to describe the composition of serum microbiome in the AMI and UA by 16S rDNA sequencing.

METHODS

Based on the high-throughput detection platform and 16S rDNA amplification sequencing technology, this study detected the blood microbial composition of 55 patients with AMI and 62 patients with UA. Alpha diversity and Beta diversity analysis were used to compare the differences in microbial composition and bacterial colony structure between AMI and UA groups. We perform PCoA (Principal Co-ordinates Analysis) based on Unweighted Unifrac distance. In addition, various statistical methods were employed to examine the significance of differences in microbial composition and genus between the two groups. PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was employed to predict KEGG (Kyoto Encyclopedia of Genes and Genomes) function from 16S sequencing data. Random forest was applied to identify biomarkers and construct the diagnostic model. Subsequently, the stability of the model was verified by 10-fold cross and the diagnostic effectiveness was evaluated through ROC (Receiver Operating Characteristic).

RESULTS

In this study, we found that alpha diversity index of serum microbiome in AMI group was significantly higher than in UA group. T-test analysis demonstrated that the UA group presented a higher abundance of Ralstonia, Faecalibaculum and Gammaproteobacteria, while Bacteroides, Sphingomonas, Faecalibaculum, Haemophilus, Serratia, Bifidobacterium and Chloroplast were more abundant in the AMI group. The LefSe (LDA Effect Size) analysis showed that the Gammaproteobacteria, Proteobacteria, Ralstonia pickettli, Ralstonia, Burkholderiaceae and Burkholderiales were enriched in UA group, and Bacteroidales, Bacteroidia, Bacteroidota, Clostridia and Firmicutes were more abundant in the AMI group. Ten bacterial diagnostic models were constructed in the random forest. The area under the curve (AUC) in the training set was 88.01%, and the AUC value in the test set was 95.04%.

CONCLUSION

In this study, the composition of blood microorganisms in the groups of patients with AMI and UA has been analyzed, providing novel insights for understanding the pathogenesis of AMI; Blood microbiome may serve as novel diagnostic biomarkers of AMI.

Association of enhanced circulating trimethylamine N-oxide with vascular endothelial dysfunction in periodontitis patients

BACKGROUND

Accumulating evidences indicate that periodontitis is closely associated with endothelial dysfunction. Trimethylamine-N-oxide (TMAO), a harmful microbiota generated metabolite, has been implicated as a nontraditional risk factor for impaired endothelial function. However, whether increased circulating levels of TMAO in periodontitis patients induces endothelial dysfunction remains unknown.

METHODS

Patients with periodontitis and periodontally healthy controls were enrolled. Periodontal inflamed surface area (PISA) was calculated to assess the inflammatory burden posed by periodontitis. The circulating TMAO was measured by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). Vascular endothelial function including peripheral endothelial progenitor cells (EPCs), brachial arterial flow-mediated vasodilation (FMD), and brachial-ankle pulse wave velocity (baPWV) were assessed. We also isolated and cultured EPCs from participants' peripheral blood to investigate the effect of TMAO on EPC functions in vitro.

RESULTS

One hundred and twenty two patients with Stage III-IV periodontitis and 81 healthy controls were included. Patients with periodontitis presented elevated TMAO (P = 0.002), lower EPCs (P = 0.025), and declined FMD levels (P = 0.005). The TMAO concentrations were correlated with reduced circulating EPCs and FMD levels. Moreover, TMAO can injury EPCs function in vitro, and may induce cell pyroptosis via Bax/caspase-3/GSDME pathway.

CONCLUSIONS

The present study demonstrates for the first time that circulating TMAO levels are increased in patients with Stage III-IV periodontitis, and correlated with vascular endothelial dysfunction. These findings may provide a novel insight into the mechanism of vascular endothelial dysfunction in patient with periodontitis via TMAO-downregulated EPC functions.

Effect of periodontal disease on oxidative stress markers in patients with atherosclerosis

OBJECTIVES

The aim of this study was to investigate the effect of periodontal inflammation on oxidative stress in patients with atherosclerosis by considering serum and saliva total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI).

MATERIALS AND METHODS

In the study, there were 4 groups, with 20 individuals in each group. These groups consisted of individuals who had periodontitis with atherosclerosis (group A-P), were periodontally healthy with atherosclerosis (group A-C), were systemically healthy with periodontitis (group P), and were systemically and periodontally healthy (group C). Clinical periodontal parameters were recorded. PISA values were calculated. Atherosclerosis severity was determined by the Gensini score. The ratio of TAS/TOS resulting in the OSI levels of the serum and saliva samples was examined biochemically.

RESULTS

Group A-P serum TAS and group C saliva OSI values were lower than those of the other groups (p < 0.05). Group A-P serum TOS and OSI values were higher than those of the other groups (p < 0.05). Groups A-C and P serum TOS and OSI values were higher than those of group C (p < 0.05). In the multivariate linear regression analysis, group A-P and PISA values were independently associated with serum TOS and OSI values (p < 0.05). Group A-P, group P, and PISA values were independently associated with saliva OSI values (p < 0.05).

CONCLUSIONS

Periodontitis and atherosclerosis may have systemic oxidative stress-increasing effects. The coexistence of periodontitis and atherosclerosis increases oxidative stress beyond that seen in either condition alone. Periodontitis can be associated with increased systemic TOS and OSI values in patients with atherosclerosis.

STATEMENT OF CLINICAL RELEVANCE

Oxidative status is affected more severely when periodontitis and atherosclerosis coexist rather than when either exists alone. Periodontitis can cause increasing effect on serum TOS and OSI and decreasing effect on TAS in patients with atherosclerosis. The increase in oxidative stress markers with the presence of periodontal disease in patients with atherosclerosis emphasizes that controlling periodontal diseases, a treatable disease, may contribute to the prognosis of atherosclerosis.

Relationship of periodontitis and edentulism to angiographically diagnosed coronary artery disease: A cross-sectional study

OBJECTIVE

The objective of the study is to examine the connection between oral status and the extent of coronary artery disease (CAD), which is diagnosed by angiography.

BACKGROUND

Periodontitis and tooth loss have been linked to atherosclerosis and CAD in previous studies. However, no distinct connection was revealed due to the diversity of the results and the variety of diagnostic methods. To provide a more consistent data pool and stronger evidence, there is a need for studies with standard measurements and diagnostic criteria.

METHODS

309 patients, who consulted to Ankara University, Faculty of Medicine, Department of Cardiology and had coronary angiography, were enrolled to this study. Individuals were grouped based on their coronary angiography results, as CAD (+) (n = 233) and CAD (-) (n = 76). Studied parameters included cardiovascular risk factors, plaque index (PI), remaining teeth count, bleeding on probing (BOP), and probing pocket depth (PPD). Periapical radiographs were taken from teeth with ≥4 mm PPD. Oral status was categorized as periodontally healthy subjects/patients with gingivitis (Group 1), patients with periodontitis (Group 2), and edentulous subjects (Group 3).

RESULTS

PI (P < 0.001), PPD (P = 0.001), BOP (P = 0.004), the number of patients with less than 10 teeth (P = 0.014), and edentulism (P = 0.009) were significantly higher in CAD (+) patients, who were mostly older (P < 0.001) and male (P < 0.001). Multivariate logistic regression analysis revealed that Group 2 (odds ratio = 2.48, 95% confidence interval = 1.24-4.95, P = 0.010) and Group 3 (odds ratio = 2.01, 95% confidence interval = 1.14-5.17, P = 0.040) were highly associated with CAD. Two and three stenosed vessels were significantly higher in Groups 2 and 3 compared to Group 1 (P = 0.003).

CONCLUSIONS

It was found that both edentulism and periodontitis were related to CAD.

Association of tumor necrosis factor-α (TNF-α) gene promoter polymorphisms with aggressive and chronic periodontitis in the eastern Indian population

Background: Periodontitis is a very common inflammatory oral disease. Tumor necrosis factor-α (TNF-α) is a cytokine that has been involved with the gingival tissue destruction and remodeling occurrence. We investigated the association of single nucleotide polymorphisms (SNPs) in TNF-α gene promoter region with the susceptibility of aggressive and chronic periodontitis in the eastern Indian population.

Methods: A total of 397 DNA samples from venous blood were isolated. 40 individuals were aggressive periodontitis patients, 157 were identified chronic periodontitis patients, and the remaining 200 were healthy individuals. Five SNPs of TNF-α at promoter region (rs361525, rs1800629, rs1799724, rs1800630, and rs1799964) were genotyped by PCR-sequencing in periodontitis patients and control subjects.

Results: rs1800629 (-308G/A) polymorphism was more frequent in both aggressive and chronic periodontitis patients compared with the control population, though the allele frequency was different only in aggressive periodontitis patients. On the other hand, both the genotypic and allelic variation of rs361525 (-238G/A) polymorphism were found significantly less frequently in aggressive and chronic periodontitis than in controls. The other polymorphisms like rs1799724 (-857C/T) and rs1799964 (-1031T/C) were significantly different between chronic periodontitis patients and control subjects.

Conclusion: The findings suggest that the rs1800629 (-308G/A) polymorphism of TNF-α gene is associated with both aggressive and chronic periodontitis while rs1799724 (-857C/T) and rs1799964 (-1031T/C) polymorphisms of TNF-α gene is associated only with the increased susceptibility to chronic periodontitis.

Periodontitis and Alzheimer's Disease: A Possible Comorbidity between Oral Chronic Inflammatory Condition and Neuroinflammation

Periodontitis is an oral chronic infection/inflammatory condition, identified as a source of mediators of inflammation into the blood circulation, which may contribute to exacerbate several diseases. There is increasing evidence that inflammation plays a key role in the pathophysiology of Alzheimer’s disease (AD). Although inflammation is present in both diseases, the exact mechanisms and crosslinks between periodontitis and AD are poorly understood. Therefore, this article aims to review possible comorbidity between periodontitis and AD. Here, the authors discuss the inflammatory aspects of periodontitis, how this oral condition produces a systemic inflammation and, finally, the contribution of this systemic inflammation for worsening neuroinflammation in the progression of AD.

Effect of Intensive Periodontal Therapy on Blood Pressure and Endothelial Microparticles in Patients With Prehypertension and Periodontitis: A Randomized Controlled Trial

BACKGROUND

Although some studies show a positive association between periodontitis and blood pressure (BP) elevation, research on the effect of intensive periodontal treatment on decline in BP levels and endothelial microparticles (EMPs) without any antihypertensive management is lacking. Therefore, the present clinical trial explores whether intensive periodontal therapy would lower BP levels and EMPs of patients with prehypertension with periodontitis.

METHODS

From a total 107 patients, 95 underwent randomization (47 assigned to control-treatment [CT] group and 48 assigned to intensive-treatment [IT] group) and completed the trial. Patients received intervention for 4 consecutive weeks and were followed for 6 months. Levels of BP and EMPs were evaluated at baseline and 1, 3, and 6 months after intervention.

RESULTS

Periodontal conditions were significantly improved (P <0.05) 6 months after intensive periodontal treatment. In parallel, the primary outcomes including systolic and diastolic BP and EMPs were markedly reduced in the IT group compared with the CT group (absolute difference: 12.57 and 9.65 mm Hg and 581.59/μL, respectively; 95% confidence intervals: 10.45 to 14.69, 7.06 to 12.24, and 348.12 to 815.06, respectively; P <0.05). Reduction in BP levels and EMPs was related to improvement in probing depth (r = 0.358, 0.363, and 0.676, respectively, by the Pearson product-moment correlation; P = 0.009, 0.008, and P <0.001, respectively).

CONCLUSION

To the best knowledge of the authors, the present study demonstrates for the first time that intensive periodontal intervention without any antihypertensive medication therapy may be an effective means to lower levels of BP and EMPs in patients with prehypertension with periodontitis.

Decreased circulating neopterin is associated with increased arterial elasticity: a beneficial role of periodontal treatment

BACKGROUND

The aim of this study was to evaluate the effect of periodontal treatment on arterial elasticity and circulating neopterin in patients with moderate to severe periodontitis in a Chinese population.

METHODS

One hundred and eight patients with moderate to severe periodontitis were eligible to take part in the study and were randomized into two groups. The treatment group received intensive periodontal treatment, while the control group received control periodontal treatment. All parameters, including brachial-ankle pulse wave velocity (baPWV), ankle brachial index (ABI), serum neopterin (NP), high-sensitivity C-reactive protein (hs-CRP), Interleukin-6 (IL-6), were evaluated before treatment and 1 month after treatment.

RESULTS

The parameters including NP, hs-CRP, IL-6 and baPWV decreased significantly after 1 month in the treatment group (p < 0.05 for all comparisons) but not in the control group (p > 0.05). There was no significant difference in the change of ABI between the two groups (p = 0.231). A positive correlation was found between the decreased circulating NP and increased arterial elasticity in the treatment group (r = 0.947, p < 0.001).

CONCLUSIONS

This study demonstrates for the first time that the fall in circulating NP induced by periodontal treatment contributes to increased arterial elasticity in patients with moderate and severe periodontitis.

The dormant blood microbiome in chronic, inflammatory diseases

Blood in healthy organisms is seen as a ‘sterile’ environment: it lacks proliferating microbes. Dormant or not-immediately-culturable forms are not absent, however, as intracellular dormancy is well established. We highlight here that a great many pathogens can survive in blood and inside erythrocytes. ‘Non-culturability’, reflected by discrepancies between plate counts and total counts, is commonplace in environmental microbiology. It is overcome by improved culturing methods, and we asked how common this would be in blood. A number of recent, sequence-based and ultramicroscopic studies have uncovered an authentic blood microbiome in a number of non-communicable diseases. The chief origin of these microbes is the gut microbiome (especially when it shifts composition to a pathogenic state, known as ‘dysbiosis’). Another source is microbes translocated from the oral cavity. ‘Dysbiosis’ is also used to describe translocation of cells into blood or other tissues. To avoid ambiguity, we here use the term ‘atopobiosis’ for microbes that appear in places other than their normal location. Atopobiosis may contribute to the dynamics of a variety of inflammatory diseases. Overall, it seems that many more chronic, non-communicable, inflammatory diseases may have a microbial component than are presently considered, and may be treatable using bactericidal antibiotics or vaccines.

Atopobiosis of microbes (the term describing microbes that appear in places other than where they should be), as well as the products of their metabolism, seems to correlate with, and may contribute to, the dynamics of a variety of inflammatory diseases.