Graphical Schematic diagram depicting the process of F. nucleatum inducing atherosclerosis. As one of the oral commensal bacteria, F. nucleatum is abundant in periodontitis sites and can enter blood circulation through damaged periodontal tissue. Subsequently, there is an increase in risk factors (dyslipidemia and inflammatory mediators) in the blood circulation. In addition, it has high invasiveness and can invade into the vascular intima, promoting macrophages M1 polarization, aberrant lipid metabolism, and cell apoptosis, thereby increasing the release of inflammatory mediators, and the degradation of extracellular matrix in the atherosclerotic plaque microenvironment. By then, plaques are prone to rupture.
1 January 2022 in Oxidative Medicine and Cellular Longevity
Objective. In periodontitis, excessive oxidative stress combined with subsequent apoptosis and cell death further exacerbated periodontium destruction. TRPA1, an important transient receptor potential (TRP) cation channel, may participate in the process. This study is aimed at exploring the role and the novel therapeutic function of TRPA1 in periodontitis. Methods. Periodontal ligament cells or tissues derived from healthy and periodontitis (PDLCs/Ts and P‐PDLCs/Ts) were used to analyze the oxidative and apoptotic levels and TRPA1 expression. TRPA1 inhibitor (HC030031) was administrated in inflammation induced by P. gingivalis lipopolysaccharide (P.g.LPS) to investigate the oxidative and apoptotic levels of PDLCs. The morphology of the endoplasmic reticulum (ER) and mitochondria was identified by transmission electron microscope, and the PERK/eIF2α/ATF‐4/CHOP signal pathways were detected. Finally, HC030031 was administered to periodontitis mice to evaluate its effect on apoptotic and oxidative levels in the periodontium and the relieving of periodontitis. Results. The oxidative, apoptotic levels and TRPA1 expression were higher in P‐PDLC/Ts from periodontitis patients and in P.g.LPS‐induced inflammatory PDLCs. TRPA1 inhibitor significantly decreased the intracellular calcium, oxidative stress, and apoptosis of inflammatory PDLCs and decreased ER stress by downregulating PERK/eIF2α/ATF‐4/CHOP pathways. Meanwhile, the overall calcium ion decrease induced by EGTA also exerted similar antiapoptosis and antioxidative stress functions. In vivo, HC030031 significantly reduced oxidative stress and apoptosis in the gingiva and periodontal ligament, and less periodontium destruction was observed. Conclusion. TRPA1 was highly related to periodontitis, and TRPA1 inhibitor significantly reduced oxidative and apoptotic levels in inflammatory PDLCs via inhibiting ER stress by downregulating PERK/eIF2α/ATF‐4/CHOP pathways. It also reduced the oxidative stress and apoptosis in periodontitis mice thus ameliorating the development of periodontitis.
Periodontitis is a chronic inflammatory disease initiated by biofilm microorganisms and mediated by host immune imbalance. Uncontrolled periodontal infections are the leading cause of tooth loss in adults. Thrombotic diseases can lead to partial or complete obstruction of blood flow in the circulatory system, manifesting as organ or tissue ischemia and necrosis in patients with arterial thrombosis, and local edema, pain and circulatory instability in patients with venous thrombosis, which may lead to mortality or fatality in severe case. Recent studies found that periodontitis might enhance thrombosis through bacterial transmission or systemic inflammation by affecting platelet-immune cell interactions, as well as the coagulation, and periodontal therapy could have a prophylactic effect on patients with thrombotic diseases. In this review, we summarized clinical findings on the association between periodontitis and thrombotic diseases and discussed several novel prothrombotic periodontitis-related agents, and presented a perspective to emphasize the necessity of oral health management for people at high risk of thrombosis.
Streptococcus mutans SpaP mediates the binding of this cariogenic bacteria to tooth surfaces. It was reported that the SpaP of S. mutans clinical isolates could be classified to 2 genotypes, type A and B. Our aims are to examine spaP genotypes in often-used S. mutans laboratory strains as well as clinical isolates and to explore the relationship between the genotypes of S. mutans strains and their adherence to salivary-agglutinin (SAG). The sequences of SpaP of 11 S. mutans strains were analyzed with alignment tools. Out of these strains, 9 strains were examined for their adherence to SAG-coated surfaces. The SpaP expression on the cell surfaces and in the spent media of 9 strains were examined by a dot-blot assay. Based on the alignment of the variable V region of SpaP, 9 strains were classified as previously-defined type-A and 3 strains type-B. Among type-B strains, the SpaPs of GS5 and HG723 contain a premature stop codon which resulted in loss of adherence and absence of SpaP expression on the cell surfaces. However, clear SpaP expression was observed in the spent media of both strains. The type-B strain UA159 demonstrated low SpaP expression on the cell surface, but it showed similar adherence ability as the type-A strains. In conclusion, the presence of SpaP on the cell surface determines the adherence of S. mutans to SAG. No difference in SAG-mediated adherence could be seen between type A and B strains, probably due to the limited number of type B strain tested.
Objectives: The objective of this study was to examine the association between the oral microbiome and pregnancy outcomes, specifically healthy or preterm low birth weight (PLBW) in individuals with and without periodontal disease (PD). Material and methods: In this prospective clinical trial, we recruited 186 pregnant women, 17 of whom exhibited PD and delivered PLBW infants (PD-PLBW group). Of the remaining women, 155 presented PD and delivered healthy infants; 18 of these subjects with similar periodontal condition and age matched to the PD-PLBW group, and they became the PD-HD group. From the total group, 11 women exhibited healthy gingiva and had a healthy delivery (HD) and healthy infants (H-HD group), and 3 exhibited healthy gingiva and delivered PLBW infants (H-PLBW group). Periodontal parameters were recorded, and subgingival plaque and serum were collected during 26–28 gestational weeks. For the plaque samples, microbial abundance and diversity were accessed by 16S rRNA sequencing. Results: Women with PD showed an enrichment in the genus Porphyromonas, Treponema, and Filifactor, whereas women with healthy gingiva showed an enrichment in Streptococcus, Actinomyces, and Corynebacterium, independently of the birth status. Although no significant difference was found in the beta diversity between the 4 groups, women that had PLBW infants presented a significantly lower abundance of the genus Neisseria, independently of PD status. Conclusion: Lower levels of Neisseria align with preterm low birth weight in pregnant women, whereas a higher abundance of Treponema, Porphyromonas, Fretibacterium, and Filifactor and a lower abundance of Streptococcus may contribute to periodontal disease during pregnancy. Clinical relevance: The oral commensal Neisseria have potential in the prediction of PLBW.