Association between metabolic syndrome and periodontitis: The role of lipids, inflammatory cytokines, altered host response, and the microbiome

The role of cellular lipid metabolism and lipid-lowering drugs in periodontitis

Initiated by bacteria, periodontitis (PD) is a complex, chronic inflammatory disease of the supporting tissue of the gums and teeth. Also linked to PD include human papillomavirus (HPV), hepatitis B virus (HBV), Epstein-Barr virus (EBV), human cytomegalovirus (CMV), and Herpes Simplex Virus (HSV). PD also raises the risk of cardiovascular disease (CVD) because it triggers inflammatory reactions throughout the body. CVD and chronic PD were linked to significantly elevated levels of C-reactive protein and blood lipids. Furthermore, elevated lipid peroxidation (LPO) levels may influence PD-related inflammation and periodontium degradation. In addition, there was a correlation between a reduction in oxidized low-density lipoprotein (LDL) levels and a reduction in circulating oxidative stress (OS); this was shown to be achieved by improved dental hygiene and non-surgical periodontal treatment. Consequently, this research set out to examine the connections between lipid metabolism and PD, as well as the effects of PD on the efficacy of statins and other medications that decrease cholesterol, as well as inhibitors and other lipid-lowering agents. Additionally, it's worth mentioning that statins and other cholesterol-lowering drugs may affect gum and tooth health. We found that higher blood levels of bad cholesterol exacerbate PD. Furthermore, PD makes CVD worse. The involvement of proprotein convertase subtilisin/kexin type 9 (PCSK9) in bacterial infections and the development of PD is inversely proportional to the increase in LDL levels. The treatment of this disease could, therefore, benefit greatly by inhibiting this chemical. Medications that lower cholesterol levels may potentially help treat this problem. The possible side effects of this medication on PD patients need more investigation. We have reviewed the literature on PD and its relationship to lipid metabolism, LDL receptors, and lipid rafts. Afterward, we investigated the role of lipid metabolism in the local viral infection that causes PD. Lastly, we examined how statins and other lipid-lowering medications impact PD.

Regulation of osteoclast-mediated bone resorption by lipids

Hyperactivation of osteoclasts has been identified as a significant etiological factor in several bone resorption-related disorders, including osteoporosis, periodontitis, arthritis, and bone metastasis of tumors. It has been demonstrated that the severity of these diseases is influenced by lipids that regulate osteoclast differentiation and activity through specific signaling pathways and cytokine levels. The regulatory mechanisms of different types of lipids on osteoclastogenesis vary across diverse disease contexts in bone resorption regulated by osteoclasts. This review presents an overview of the mechanisms underlying osteoclast formation and summarizes the pathways through which various lipids regulate osteoclastogenesis in different pathological contexts. We also discuss effective therapeutic strategies for osteolytic diseases based on modulation of lipid metabolism.

Testing the Causal Association Between Metabolic Syndrome and Periodontitis: A Two-sample Mendelian Randomisation Study

INTRODUCTION AND AIMS

Observational studies suggest an association between metabolic syndrome (MetS) and periodontitis. However, observational studies are susceptible to reverse causation and confounding factors, so the causality of this association is uncertain. Causal association between compounds of MetS and periodontitis has been well studied. Using Mendelian randomisation (MR), we aimed to comprehensively evaluate the bidirectional relationship between MetS as a whole and periodontitis and provide clinical insight.

METHODS

We used genetic instruments from the most comprehensive genome-wide association studies of European descent for MetS (n = 291,107) as well as periodontitis from both the FinnGen consortium (n = 195,395) and GeneLifestyle Interactions in Dental Endpoints (GLIDE, n = 45,563) consortium to investigate the causal relationship between MetS and periodontitis and vice versa. We used the inverse-variance weighted (IVW) method to derive the primary causal estimates and evaluated the robustness of our results with a series of sensitivity analyses.

RESULTS

MR analysis based on FinnGen consortium indicated a negative causal association of MetS on periodontitis (OR = 0.882, 95% CI = 0.791-0.983, P = .023), while MR analysis based on GLIDE consortium did not support a causal relation of MetS on periodontitis (OR = 0.986, 95% CI = 0.920-1.057, P = .697). These results were consistent after adjusting for potential confounding factors by multivariable MR analyses. Results from meta analysis did not support a causal association of MetS on periodontitis. Sensitivity analysis showed that there was no existence of pleiotropy. In the reverse direction, periodontitis showed no association with MetS.

CONCLUSIONS

Within the scope of this MR study, MetS and periodontitis are not causally related.

CLINICAL RELEVANCE

Further studies are needed to clarify the underlying mechanism between metabolic syndrome and periodontitis.

Alpha-Ketoglutarate Alleviates Systemic Lupus Erythematosus-Associated Periodontitis in a Novel Murine Model

AIM

To establish a reproducible experimental animal model for systemic lupus erythematosus (SLE)-associated periodontitis (PD), investigate the effects of SLE on PD and assess the therapeutic potential of alpha-ketoglutarate (αKG) for SLE-PD treatment.

MATERIALS AND METHODS

An SLE-PD murine model was established via ligature-induced PD in MRL-lpr strain, with MRL/MpJ strain as a non-SLE control. The periodontal state was assessed using micro-CT, real-time PCR, histology, immunofluorescence and flow cytometry assays. αKG levels were analysed, and a thermoresponsive gel was designed as a periodontal dimethyl (DM)-αKG delivery system. αKG levels were analysed in gingival crevicular fluid (GCF) of PD patients with or without SLE.

RESULTS

SLE significantly increased the periodontal inflammation and bone resorption in the SLE-PD model. αKG levels in GCF were lower in PD patients with SLE than in PD patients without SLE. Decreased αKG levels in the gingiva and macrophage M1/M2 imbalance were observed in SLE-PD mice. However, DM-αKG thermoresponsive gel effectively alleviated the periodontal inflammation, bone resorption and macrophage M1/M2 imbalance in SLE-PD mice.

CONCLUSIONS

Our study established, for the first time, a novel SLE-PD murine model and revealed that SLE increases the severity of PD in vivo. Our findings highlight the therapeutic potential of αKG for SLE-associated PD.

Development of a machine learning model related to explore the association between heavy metal exposure and alveolar bone loss among US adults utilizing SHAP: a study based on NHANES 2015-2018

BACKGROUND

Alveolar bone loss (ABL) is common in modern society. Heavy metal exposure is usually considered to be a risk factor for ABL. Some studies revealed a positive trend found between urinary heavy metals and periodontitis using multiple logistic regression and Bayesian kernel machine regression. Overfitting using kernel function, long calculation period, the definition of prior distribution and lack of rank of heavy metal will affect the performance of the statistical model. Optimal model on this topic still remains controversy. This study aimed: (1) to develop an algorithm for exploring the association between heavy metal exposure and ABL; (2) filter the actual causal variables and investigate how heavy metals were associated with ABL; and (3) identify the potential risk factors for ABL.

METHODS

Data were collected from National Health and Nutrition Examination Survey (NHANES) between 2015 and 2018 to develop a machine learning (ML) model. Feature selection was performed using the Least Absolute Shrinkage and Selection Operator (LASSO) regression with 10-fold cross-validation. The selected data were balanced using the Synthetic Minority Oversampling Technique (SMOTE) and divided into a training set and testing set at a 3:1 ratio. Logistic Regression (LR), Support Vector Machines (SVM), Random Forest (RF), K-Nearest Neighbor (KNN), Decision Tree (DT), and XGboost were used to construct the ML model. Accuracy, Area Under the Receiver Operating Characteristic Curve (AUC), Precision, Recall, and F1 score were used to select the optimal model for further analysis. The contribution of the variables to the ML model was explained using the Shapley Additive Explanations (SHAP) method.

RESULTS

RF showed the best performance in exploring the association between heavy metal exposure and ABL, with an AUC (0.88), accuracy (0.78), precision (0.76), recall (0.83), and F1 score (0.79). Age was the most important factor in the ML model (mean| SHAP value| = 0.09), and Cd was the primary contributor. Sex had little effect on the ML model contribution.

CONCLUSION

In this study, RF showed superior performance compared with the other five algorithms. Among the 12 heavy metals, Cd was the most important factor in the ML model. The relationship of Co & Pb and ABL are weaker than that of Cd. Among all the independent variables, age was considered the most important factor for this model. As for PIR, low-income participants present association with ABL. Mexican American and Non-Hispanic White show low association with ABL compared to Non-Hispanic Black and other races. Gender feature demonstrates a weak association with ABL. In the future, more advanced algorithms should be developed to validate these results and related parameters can be tuned to improve the accuracy of the model.

CLINICAL TRIAL NUMBER

not applicable.

New Advances in Periodontal Functional Materials Based on Antibacterial, Anti-Inflammatory, and Tissue Regeneration Strategies

With the global population aging, awareness of oral health is rising. Periodontitis, a widespread bacterial infectious disease, is gaining attention. Current novel biomaterials address key clinical issues like bacterial infection, gum inflammation, tooth loosening, and loss, focusing on antibacterial, anti-inflammatory, and tissue regeneration properties. However, strategies that integrate the advantages of these biomaterials to achieve synergistic therapeutic effects by clearing oral biofilms, inhibiting inflammation activation, and restoring periodontal soft and hard tissue functions remain very limited. Recent studies highlight the link between periodontitis and systemic diseases, underscoring the complexity of the periodontal disease. There is an urgent need to find comprehensive treatment plans that address clinical requirements. Whether by integrating new biomaterials to enhance existing periodontal treatments or by developing novel approaches to replace traditional therapies, these efforts will drive advancements in periodontitis treatment. Therefore, this review compares novel biomaterials with traditional treatments. It highlights the design concepts and mechanisms of these functional materials, focusing on their antibacterial, anti-inflammatory, and tissue regeneration properties, and discusses the importance of developing comprehensive treatment strategies. This review aims to provide guidance for emerging periodontitis research and to promote the development of precise and efficient treatment strategies.

Experimental Murine Periodontitis Increases Salivary Gland IgA-Producing B Cells Following Oral Dysbiosis

The oral microbiome is closely involved in the maintenance of host health and the development of systemic diseases. The salivary glands play an essential role in homeostasis in the oral cavity. Here, we investigated the effects of periodontal inflammation on salivary gland function and the oral microbiome. In experimental periodontitis model mice, an increase in IgA⁺ cells in the salivary glands were observed 1 week after treatment. Alteration of the oral microbiome was also induced in this model. Gene expression analysis of the salivary glands showed changes in the expression of genes related to B-cell maturation and plasma cell differentiation and an increase in the expression of genes related to macrophage activation upon experimental periodontitis induction. Furthermore, the relationship between disruption of oral microflora and salivary gland function was examined using a cohousing model in which experimental periodontitis model mice and untreated mice were reared in the same cage. We found that cohoused normal mice underwent alteration of the oral microbiome, with increases in IgA⁺ cells and macrophages in the salivary glands. In summary, our results suggest that, in the oral cavity, there is a close link between oral bacterial flora and immune cells in the salivary glands. Our results also show that localized inflammation disrupts the homeostasis in the oral cavity, inducing pathological conditions such as dysbiosis. Our study suggests the importance of the interaction among local oral inflammation, salivary gland function, and oral microflora, and provides new insights into the mechanisms by which oral health is maintained.

Investigation of the preventive effect of methylsulfonylmethane on alveolar bone loss and oxidative stress in a rat model of periodontitis

BACKGROUND

To investigate the preventive efficacy of methylsulfonylmethane (MSM) on alveolar bone destruction in rats with periodontitis.

METHODS

Twenty-four male Sprague-Dawley rats were randomly divided into three groups: control, experimental periodontitis (Ep), and Ep-MSM. Periodontitis was induced by placing 4.0 silk sutures in the subparamarginal position on the necks of the mandibular first molars and applying the suture for 5 weeks. The Ep-MSM group was given 500 mg/body weight/day MSM intraperitoneally for 35 days. At the end of the study, bilateral mandibular samples were taken. Periodontal bone loss was measured through histologic sections. Histomorphometric and immunohistochemical (receptor activator of nuclear factor kappa B ligand (RANKL), osteoprotegerin (OPG)) evaluations were performed on right mandibular tissue samples, and biochemical (interleukin (IL)-1 beta (β)/IL-10, malondialdehyde (MDA), glutathione (GSH), oxidative stress index (OSI)) evaluations were performed on left mandibular tissue samples.

RESULTS

No significant difference was found between the groups in IL-1β and IL-1β/IL-10 values ​​(p > 0.05). A significant decrease in IL-10 levels was observed in the Ep-MSM and Ep groups compared with the control group (p < 0.05). MDA levels significantly increased in the Ep and Ep-MSM groups compared with the control group, and GSH levels significantly decreased in the Ep group compared with the other groups (p < 0.05). OSI values ​​were significantly higher only in the Ep group (p < 0.05). RANKL levels showed a significant increase in the Ep group compared with the other groups. OPG levels were significantly increased only in the Ep-MSM group (p < 0.05).

CONCLUSIONS

The results of this study may suggest that MSM has preventive effects on alveolar bone loss and oxidative stress.

Elimination of oral foci of infection might lead to clinical improvement of Graves' orbitopathy

PURPOSE

Graves' disease (GD) and Graves' orbitopathy (GO) are multifactorial disorders with links to the gut microbiome and autoimmunity. It is observed that patients with GD exhibit altered gut microbiome diversity. However, little is known about the role of oral microbiota in GD and GO. This study aims to investigate the impact of oral health and oral sanitation on the clinical course of GO in patients disqualified from glucocorticoid treatment due to oral infections.

METHODS

We reviewed 188 admissions of 127 patients with GO, hospitalized in a tertiary university hospital. Clinical, biochemical, imaging, ophthalmological, and oral health assessment data from each admission were analyzed. Patients excluded from the glucocorticoids (GCs) therapy due to oral foci of infection had the clinical activity score (CAS) reassessed after three months, and they were divided into two groups: with and without improvement.

RESULTS

Finishing dental treatment in the meantime was the only factor significantly correlated with improvement in these patients (p = 0.041). The secondary finding was that anti-thyroid peroxidase antibodies titer was significantly higher in the group with oral foci of infection considered as a contraindication for GCs (medians 28.50 vs 128.00; p = 0.026), and those patients were more likely to smoke than the group without oral issues (p = 0.024).

CONCLUSIONS

The results of our study suggest that monitoring and treating oral diseases may be pertinent in patients with GO and might serve as a supportive treatment strategy for managing the condition.

KEY MESSAGES

What is known: There is a recognized link between gut dysbiosis and the autoimmune processes in Graves' Disease (GD) and Graves' Orbitopathy (GO).

WHAT IS NEW

Elevated levels of TPOAb have been observed in patients with GO who also have oral foci of infection. Dental treatment has been shown to lead to significant clinical improvements in patients with GO. Maintaining oral hygiene might serve as a supportive treatment strategy for managing GO.

Association between metabolic syndrome and salivary MMP-8, myeloperoxidase in periodontitis

OBJECTIVE

This study investigated the effect of metabolic syndrome (MetS) on periodontal clinical parameters and salivary biomarkers' matrix metalloproteinase-8 (MMP-8) and myeloperoxidase (MPO) in patients with periodontitis.

METHODS

A total of 120 participants aged 25-55 were categorized into three groups: MetS with periodontitis (n = 40); systemically healthy with periodontitis (n = 40); and systemically and periodontally healthy controls (n = 40). Data collected included systemic parameters like waist circumference (WC), blood pressure (BP), high- and low-density lipoproteins, triglycerides (TG), fasting blood sugar (FBS), and glycated hemoglobin (HbA1c). Periodontal parameters estimated included bleeding on probing score (BoP), full-mouth plaque score (FMPS), periodontal probing depth (PPD), clinical attachment loss (CAL), and the number of missing teeth. Unstimulated whole saliva was analyzed via ELISA for active MMP-8 (aMMP-8), total MMP-8 (tMMP-8), and MPO.

RESULTS

Participants with MetS and periodontitis exhibited significantly higher periodontal parameters, salivary aMMP-8, and MPO (26.26 vs. 24.1 ng/mL and 13.53 vs. 11.55 ng/mL compared to systemically healthy periodontitis patients) (all p < 0.01). Positive correlations occurred between aMMP-8 and WC, TG, and FBS (p < 0.01), and between MPO and WC, BP, and TG (p < 0.01).

CONCLUSIONS

The positive associations between these biomarkers and metabolic parameters indicate their potential utility for monitoring cardiovascular and glycemic risk in patients with periodontal disease.

Periodontitis, Metabolic Syndrome and Diabetes: Identifying Patients at Risk for Three Common Diseases Using the aMMP-8 Rapid Test at the Dentist's Office

Background/Objectives: This narrative review paper highlights the multifaceted influence of dysbiotic biofilm, genetic background, host response, and environmental factors on periodontitis. It explores the roles of type I and II diabetes mellitus, gestational diabetes, and metabolic syndrome in the progression of periodontitis, drawing insights from various empirical studies and theoretical perspectives. Methods: Relevant articles were sourced using keywords in databases like PubMed/Medline, Science Direct, Scopus, and Google Scholar. Additionally, this review examines the relationship between aMMP-8 levels and increased glycemic states, as well as varying degrees of periodontitis severity. Results: The biomarker active-matrix metalloproteinase-8 (aMMP-8), produced by polymorphonuclear leukocytes (PMN), is highlighted as a reliable indicator of ongoing connective tissue degradation. Dysfunctions in PMN activity, accumulation of advanced glycation end products (AGE), and oxidative stress aggravate the periodontal inflammatory response and complications of diabetes. Traditional diagnostics of periodontitis do not provide sufficient information about the current or future disease initiation or activity of periodontitis. Conclusions: The implications of this review point to the need for monitoring periodontal health by utilizing innovative strategies like aMMP-8 point-of-care testing, using oral rinse for screening and treatment monitoring, and harnessing the potential of supportive treatments like low-dose doxycycline and light-activated mouth rinses for restoring periodontal health. Its expression in oral fluids is a promising diagnostic tool to differentiate periodontitis from gingivitis and healthy periodontium, especially when associated with systemic diseases, fostering greater collaboration among healthcare professionals.

Single-Cell and Spatial Multi-Omics Analysis Reveal That Targeting JAG1 in Epithelial Cells Reduces Periodontal Inflammation and Alveolar Bone Loss

Mucosal immunity plays a critical role in the pathogenesis of inflammatory immune diseases. This study leverages single-cell RNA sequencing, spatial transcriptomics, and spatial proteomics to compare the cellular mechanisms involved in periodontitis between humans and mice, aiming to develop precise strategies to protect the gingival mucosal barrier. We identified key conserved and divergent features in cellular landscapes and transcriptional profiles across the two species, underscoring the complexity of inflammatory responses and immune dynamics in periodontitis. Additionally, we revealed a novel regulatory mechanism by which epithelial cells modulate macrophage behavior and inflammation through the JAG1-Notch pathway. Validation through animal experiments revealed that JAG1 inhibition reduces inflammation in epithelial cells, mitigating periodontitis. Our findings advance the understanding of periodontal disease pathogenesis and highlight the importance of integrating human and animal model data to develop treatments aligned with human physiology, offering potential therapeutic targets for controlling inflammation and enhancing tissue regeneration.

The Prevalence of Metabolic Syndrome and Undiagnosed Diabetes in Periodontitis Patients and Non-Periodontitis Controls in a Dental School

Background/Objectives: Metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) are major global health concerns, and they often go undetected. Periodontitis shares risk factors and is associated with both conditions. Assessing MetS risk factors among dental patients, especially those with periodontitis, may contribute to early detection and prompt treatment. However, current information about MetS prevalence rates in dental settings is limited. Therefore, our aim was to investigate the prevalence of MetS among patients with generalized periodontitis stage III/IV (GenPD), localized periodontitis stage III/IV (LocPD), and non-periodontitis controls. We also investigated the prevalence of undiagnosed T2DM in the same population. Moreover, we performed a pilot study to evaluate the possibility of measuring fructosamine levels in oral rinse samples, as an alternative to HbA1c, to screen for hyperglycemia. Methods: Periodontitis patients and non-periodontitis controls were recruited from a dental school, all aged ≥ 40 years. MetS prevalence was determined according to four different MetS definitions. T2DM prevalence was based on elevated HbA1c levels (HbA1c ≥ 7.0%). Biochemical analysis from blood was carried out by finger stick sampling. A subset of participants was asked to provide an oral rinse sample for the measurement of fructosamine, which was correlated to HbA1c from blood. Results: A total of 105 patients with periodontitis (GenPD stage III/IV: n = 44, LocPD stage III/IV: n = 61) and 88 non-periodontitis controls, with a mean age of 54.4 years, were included. The prevalence of MetS, according to four different MetS definitions, was 68.2-81.8% in GenPD patients, 42.6-62.3% in LocPD patients, and 52.3-69.3% in controls. The prevalence of T2DM, as evidenced by elevated HbA1c, was 20.5% in GenPD patients, 18.3% in LocPD patients, and 10.2% in controls (p = 0.094). A substantial number of subjects were not aware that they were being suspected to have T2DM, i.e., 13.6% in GenPD patients, 8.2% in LocPD patients, and 8.0% in controls (p = 0.335). In a subset of participants (n = 48), we found no significant correlation between HbA1c and oral fructosamine (r= 0.24, p = 0.103). Conclusions: The overall results showed a relatively high prevalence of patients with MetS and/or elevated HbA1c among periodontitis patients and controls in the dental school. Of those with suspected T2DM, a substantial number were not aware of having T2DM. Oral health care professionals could therefore contribute to early detection for T2DM and/or create awareness in patients at risk for a disease related to MetS. To date, initial results on the use of oral fructosamine as an alternative for HbA1c cast doubt, and further research is needed.

Association between periodontal disease and systemic diseases: a cross-sectional analysis of current evidence

BACKGROUND

Numerous systematic reviews and meta-analyses have been published that evaluate the association between periodontal disease and systemic diseases, many of which address similar topics. Moreover, their quality requires assessment. Therefore, we performed a cross-sectional analysis to examine the evidence on the relationship between periodontal disease and systemic diseases.

METHODS

The PubMed, Embase, Web of Science, and the Cochrane Library databases were systematically searched to identify relevant systematic reviews and meta-analyses. Only studies that considered periodontal disease as the exposure factor and various systemic diseases as the outcome were included. The basic characteristics and pertinent data from the selected studies were extracted. The modified version of A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2) was employed for quality assessment, while R software was used for statistical analysis.

RESULTS

Among the 212 relevant systematic reviews and meta-analyses, 57 were finally included in our analysis. These studies involved 75 diseases and 81 disease-related outcomes, with cancer (19/81) being the most frequently addressed topic. Of the 81 outcomes, 67 demonstrated a significant association. Notably, the highest risk estimate was found for head and neck cancer [odds ratio (OR) = 3.17, 95% confidence interval (CI) 1.78 - 5.64], while the lowest was observed for premature rupture of the amniotic sac [relative risk (RR) = 1.10, 95% CI 1.08 - 1.12]. The methodological quality ratings indicated that approximately 71.93% of included studies were classified as "Critically low", with another 17.54% rated as "Low", and only about 10.53% categorized as "Moderate".

CONCLUSIONS

Periodontal disease significantly elevates the risks associated with 15 cancer-related, 8 cardiovascular-related, 8 metabolic-related, and 5 neurological-related outcomes. However, the overall methodological quality of existing systematic reviews and meta-analyses is generally suboptimal and requires enhancement to generate higher-quality evidence in the future.

Evaluation of the Effect of Supragingival Scaling on Periodontal Parameters in Pregnant Women with Metabolic Syndrome

Background

Although there are quite a number of studies on the impacts of periodontal therapeutic management on pregnant females, literature on the impact of supragingival scaling on pregnant females with metabolic syndrome (MS) is wanting. The present investigation was meticulously formulated to ascertain the clinical ramifications of supragingival scaling in pregnant individuals diagnosed with MS.

Material and Methods

An intervention study was conducted on 47 pregnant females. The gingival index (GI), plaque index, bleeding on probing, probing depth, and clinical attachment level were among the periodontal parameters evaluated. By the end of 20-21 weeks of pregnancy, all participants had received scaling and polishing at the baseline appointment, along with advice on dental hygiene. Periodontal parameters were gathered again during a follow-up appointment 8 weeks post treatment. A 5% threshold for statistical significance was set, and paired t-test and chi-square test were applied for comparison.

Results

Lower levels of PI, GI, and BOP 8 weeks post supragingival scaling were noted than at the baseline. The results obtained were statistically significant (P < 0.001) All patients with severe periodontitis (n = 14) before supragingival scaling shifted to milder forms of the disease. Similarly, moderate periodontitis was seen in 20 patients before the start of the study, and after the intervention, it was reduced to 16 patients.

Conclusion

In summary, supragingival scaling lowers the incidence of periodontal disease in pregnant MS females. High-risk pregnant women who receive scaling treatment and instruction on oral hygiene on a regular basis have better oral health, which in turn improves the health of their unborn child.

Assessment of the Periodontal Parameters in Pregnant Women Diagnosed with Metabolic Syndrome: A Cross-Sectional Study

Background

The prevalence of metabolic syndrome (MeS) is increasing due to modern lifestyles, making it essential to explore its connection with conditions like periodontitis, particularly in pregnant women. This study aims to evaluate the periodontal parameters health of pregnant women with metabolic syndrome.

Material and Methods

The study included 144 pregnant women aged 18-34 with MeS. Demographic data collected encompassed age, nutrition, medical history, and oral health practices. Dental exams assessed the gingival index, plaque index, bleeding on probing, probing depth, and clinical attachment loss, classifying participants into mild, moderate, and severe periodontitis. Blood glucose, triglycerides, HDL cholesterol, systolic and diastolic blood pressure, waist circumference, and BMI were measured to analyze the relationship between the number of MeS components and periodontal disease severity using a Chi-square test. A P value of less than 0.05 was considered statistically significant.

Results

Gingivitis was present in 33.3% of the subjects, whereas severe periodontitis was in 20.8%. Nonetheless, there was no discernible correlation (P > 0.05) between periodontal disease severity and MeS risk variables.

Conclusion

The majority of subjects had gingivitis, although all patients with MeS exhibited periodontal disease to some degree. However, there is still debate over whether or whether an increased presence of MeS components is associated with more severe periodontal disease, particularly during pregnancy.

The role of interleukin-20 on inflammatory stress and periodontal tissue destruction in patients with metabolic syndrome and periodontitis

BACKGROUND

There is an increasing occurrence of periodontitis and metabolic syndrome (MetS), which is resulting in a decline in the overall quality of life. Both disorders can occur together since they are both linked to insulin resistance and systemic inflammation. However, evidence for a role of interleukin (IL)-20 in this comorbidity is very limited. This cross-sectional study aimed to comprehensively investigate, for the first time, the levels of RANKL/OPG, MMP-8 and OSI as well as the role of IL-20 in patients with MetS and periodontitis.

METHODS

The study included a total of 80 individuals, divided into four groups: 20 individuals who were healthy both systemically and periodontally, 20 individuals who were systemically healthy but had periodontitis, 20 individuals who had MetS but were periodontally healthy, and 20 individuals who had both MetS and periodontitis. Periodontal clinical parameters (plaque index, gingival index, bleeding on probing, clinical attachment loss, probing pocket depth) were evaluated. Gingival crevicular fluid (GGF) and serum samples were collected and used for biochemical assays. Enzyme-linked immunosorbent assay was used to determine the levels of IL-20, receptor activator of nuclear factor kappa B ligand (RANKL)/osteoprotegerin (OPG), matrix metalloproteinase-8 (MMP-8) and oxidative stress index (OSI).

RESULTS

IL-20 levels measured in serum and GCF were statistically significantly highest in patients with MetS and periodontitis (p = 0.001). Significant positive correlation was observed between serum and GCF IL-20 values and periodontal parameters (p < 0.05). There was a positive correlation between RANKL and RANKL/OPG levels and IL-20 and clinical parameters (p < 0.05). OSI values were found to be increased in the presence of both periodontitis and MetS (p = 0.001) and were positively correlated with serum and GCF IL-20 (p < 0.05).

CONCLUSIONS

These data from the study suggest a correlation between IL-20 and both MetS and periodontitis. IL-20 may potentially worsen the condition of periodontal tissue by increasing both the oxidative stress levels, periodontal collagen degredation and the ratio of RANKL to OPG.

TRIAL REGISTRATION

This study was registered on ClinicTrials.gov (NCT06092853), 2023-10-10, retrospectively registered.

Association Between Weight-Adjusted Waist Index and Periodontitis: A Cross-Sectional Study and Mediation Analysis

Aim

The research examined the correlation between the weight-adjusted waist index (WWI) and periodontal disease, as well as the intermediary influence of triglyceride glucose (TyG) index-related indicators, utilizing a health examination dataset.

Methods

This cross-sectional study included 39,522 subjects from health check-up database of Shanghai Health and Medical Center. The WWI was determined by applying a formula that includes dividing the waist circumference (WC) by the body weight's square root. Periodontitis diagnosis followed the Centers for Disease Control and Prevention and American Academy of Periodontology (CDC/AAP) classification. The correlation between the WWI and periodontitis was investigated through multivariate logistic regression and smoothing curve fitting. Subgroup analysis and interaction tests were also performed to verify the stability of the results. A mediation analysis was conducted to quantify the direct and indirect influences mediated by the TyG-related indicators [TyG, TyG -body mass index (TyG-BMI), TyG -waist-to-height ratio (TyG-WHtR), and TyG-waist circumference (TyG-WC)].

Results

Multivariable logistic regression analysis revealed the positive association of WWI and periodontitis (OR=1.37, 95% CI: 1.30-1.43). Compared to those in the lowest quartile of WWI, participants in the highest quartile exhibited a 82% higher likelihood of periodontitis (OR=1.82, 95% CI: 1.69-1.96). Subgroup analysis and interaction tests revealed that this positive correlation was consistent in gender, BMI, WC, smoking, drinking, hypertension, and dyslipidemia (P for interaction > 0.05), with some variations noted by age and diabetes status (P for interaction<0.05). Mediation analysis showed that the proportions mediated by TyG, TyG-BMI, TyG-WC, and TyG-WHtR on the association of WWI and periodontitis risk were 13.13%, 6.30%, 16.46% and 19.79%, respectively.

Conclusion

A higher WWI in Chinese adults was linked to an increased likelihood of periodontitis, and this correlation could be partially explained by elevated levels of TyG index-related indicators.

Clinical and Microbiological Periodontal Biofilm Evaluation of Patients with Type I Diabetes

Background/Objectives: The purpose of this study was to assess the microbial composition and density of subgingival plaque samples for periodontal pathogens while correlating the values with glycemic control levels via glycated hemoglobin (HbA1c), a type of hemoglobin that has chemically linked glucose, in type I diabetes individuals who will undergo complex oral rehabilitation through orthodontic treatment and implant surgery. Methods: A cohort of 42 adults with type I diabetes were included in this study. The subjects sustained a comprehensive periodontal clinical examination as well as microbiological assessments of their subgingival plaque samples through quantitative real-time PCR. The samples were collected from the two deepest pockets of each subject. Results: The highest number of periodontopathogenic bacteria was observed in the pockets of 5-7 mm. T. forsythia showed the highest prevalence (20.48%), with decreasing numbers as follows: T. denticola (13.31%), P. gingivalis (11.26%), A. actinomycetemcomitans (7%), and P. intermedia (4.9%). T. denticola and T. forsythia were significantly more commonly observed in individuals with elevated HbA1c serum levels. No correlation was observed between P. gingivalis, A. actinomycetemcomitans, P. intermedia presence, and the HbA1c value. Conclusions: Periodontopathogenic agents' presence in subgingival biofilm samples varied in accordance with the pocket probing depth and metabolic control of the diabetic individuals. In our study, the appearance of these periodontopathogenic agents was linked to lowered metabolic control in patients with type I diabetes mellitus.

Periodontal diseases in Africa

Periodontal diseases, a group of complex conditions marked by an excessive immune response and periodontal tissue destruction, are a global health concern. Since 1990, the incidence of these diseases has doubled, with Western sub-Saharan Africa experiencing the highest burden. Accurate diagnosis and case identification are crucial for understanding the etiology, features of disease, research, treatment and prevention. Modern perspectives on periodontal disease classification are based on commonality among those affected. However, current literature is often plagued by methodological inconsistencies and focused on disease mechanisms in European populations. Health inequalities in low- and middle-income countries (LMICs) are exacerbated by these challenges, with sub-Saharan Africa, and Nigeria specifically, facing unique difficulties such as clinical personnel shortages and limited research infrastructure. This review explored disparities in periodontal disease research, care and outcomes in African populations. We highlighted these disparities and identified the factors contributing to inequities in periodontal health outcomes. We further demonstrated the critical need for inclusive and equitable healthcare and research practices tailored to the unique challenges faced by diverse populations and regions with limited resources. Addressing these disparities is essential for ensuring that advancements in healthcare are accessible to all, thereby improving global oral health and general health.

Association between salivary microbiota and tacrolimus pharmacokinetic variability in kidney transplant

Kidney transplantation (KT) serves as a highly effective treatment for end-stage renal disease (ESRD). Nonetheless, the administration of tacrolimus, a commonly used immunosuppressant in KT, faces challenges due to the lack of dependable biomarkers for its efficacy and the considerable variability in tacrolimus pharmacokinetics (TacIPV). In this study, 183 saliva samples from 48 KT recipients under tacrolimus therapy, alongside 9 healthy control samples, were subjected to 16S rRNA sequencing. The analysis revealed significant differences in the composition of salivary microbiota among KT recipients, patients with ESRD, and healthy controls. Moreover, trough blood concentrations (C0) of tacrolimus were associated with alterations in microbiota composition. Notably, Capnocytophage consistently exhibited a negative correlation in both group-level and individual trends. Furthermore, distinct taxa were identified that effectively distinguished recipients with varying TacIPV, as demonstrated by a cross-validation random forest model (mean AUC = 0.7560), with Anaerolinea emerging as a prominent contributor to the classifier. These findings suggest that salivary microbiota is closely linked to tacrolimus C0 levels and could aid clinicians in differentiating KT recipients based on TacIPV.

Periodontitis Provokes Retinal Neurodegenerative Effects of Metabolic Syndrome: A Cross-Sectional Study

BACKGROUND

This cross-sectional study aims to investigate the retino-choroidal degenerative effects of periodontitis, metabolic syndrome (Mets), and the combination of these diseases using optical coherence tomography (OCT) measurements.

METHODS

Ninety-two patients selected according to inclusion criteria were divided into four groups: systemically and periodontally healthy (control), systemically healthy periodontitis (PD), periodontally healthy metabolic syndrome (MetS), and periodontitis and metabolic syndrome combined (PD-MetS). The systemic inflammatory-oxidative effects of periodontitis and MetS were biochemically evaluated using the serum TNF-α level, IL-1β/IL-10 ratio, and oxidative stress index (OSI: TOS/TAS). Retinal (AMT, pRNFLT, and GCL + T) and choroidal (SFCT) morphometric measurements and vascular evaluations (foveal capillary density) were performed via OCT Angio with swept-source technology.

RESULTS

Both periodontitis and Mets cause systemic inflammatory stress characterized by significant increases in the IL-1β/IL-10 ratio and OSI (p < 0.05). Compared to the control group, the AMT was significantly thinner in the MetS group, the pRNFLT was significantly thinner in the PD-MetS group, and the SFCT was significantly thinner in both groups (p < 0.05). The GCL+ was slightly thicker in the Mets groups. (p > 0.05) Foveal capillary density did not differ significantly among the groups. (p > 0.05).

CONCLUSIONS

Periodontitis-related inflammatory stress alone causes changes in retinal and subfoveal choroidal thicknesses that are not statistically significant. On the other hand, when combined with Mets, it may significantly provoke the retinal neurodegenerative effects of this disease.

Screening for Systemic Diseases Associated with Dental Self-Care in Japanese Adolescents

Background: Toothbrushing is important for maintaining oral health and preventing periodontal disease. However, the association between toothbrushing and systemic diseases remains unclear in adolescence. In this study, the association between dental self-care (frequency and duration of toothbrushing) and systemic diseases/disorders in adolescents was examined. Methods: We conducted a retrospective review of mandatory medical questionnaires administered during legally mandated freshman medical checkups between 2017 and 2019 at the University of Tokyo, Japan. Out of 9376 total responses, 9098 cases involving individuals under the age of 20 were included in the analysis. Respondents were classified into three groups based on their daily toothbrushing frequency: "1 time or less", "twice", and "3 times or more". For the duration of each toothbrushing session, they were classified into three groups: "1 min or less", "2-3 min", and "4 min or more". A statistical analysis was performed by Pearson's χ2 test and multinomial logistic regression analysis. Results: Regarding frequency of daily toothbrushing: The χ2 test showed no significant relationship between frequency of toothbrushing and 17 systemic diseases/disorders. A multivariate analysis found that gingival bleeding and sex were independent factors. The risk of gingival bleeding decreased dramatically with increased frequency of toothbrushing (odds ratio (OR): 0.428; 95% confidence interval (CI), 0.366-0.501; p < 0.001). Regarding the amount of time spent on toothbrushing: The χ2 test showed atopic dermatitis and arrhythmia were significantly associated with the duration of toothbrushing (p = 0.032 and p = 0.016, respectively). In the multivariate analysis, atopic dermatitis, gingival bleeding, and sex were independent factors regarding the duration of toothbrushing; longer brushing time was associated with a lower risk of atopic dermatitis (OR: 0.731, 95% CI: 0.578-0.924, p = 0.009) and a lower risk of gingival bleeding (OR: 0.643, 95% CI: 0.567-0.729, p < 0.001). Conclusions: Dental self-care was most strongly associated with gingival bleeding, while the risk of atopic dermatitis was found to increase with shorter toothbrushing times. The results suggest that dental self-care during adolescence is important not only for oral health but also for general health.

Acceleration of HDL-Mediated Cholesterol Efflux Alleviates Periodontitis

Periodontitis (PD) is a common inflammatory disease known to be closely associated with metabolic disorders, particularly hyperlipidemia. In the current study, we demonstrated that hypercholesterolemia is a predisposing factor in the development of PD. Logistic regression analysis revealed a strong positive correlation between PD and dyslipidemia. Data from in vivo (PD mouse model subjected to a high cholesterol diet) and in vitro (cholesterol treatment of gingival fibroblasts [GFs]) experiments showed that excess cholesterol influx into GFs potentially contributes to periodontal inflammation and, subsequently, alveolar bone erosion. Additionally, we compared the protective efficacies of cholesterol-lowering drugs with their different modes of action against PD pathogenesis in mice. Among the cholesterol-lowering drugs we tested, fenofibrate exerted the most protective effect against PD pathogenesis due to an increased level of high-density lipoprotein cholesterol, a lipoprotein involved in cholesterol efflux from cells and reverse cholesterol transport. Indeed, cholesterol efflux was suppressed during PD progression by downregulation of the apoA-I binding protein (APOA1BP) expression in inflamed GFs. We also demonstrated that the overexpression of APOA1BP efficiently regulated periodontal inflammation and the subsequent alveolar bone loss by inducing cholesterol efflux. Our collective findings highlight the potential utility of currently available cholesterol-lowering medications for the mitigation of PD pathogenesis. By targeting the acceleration of high-density lipoprotein-mediated cellular cholesterol efflux, a new therapeutic approach for PD may become possible.

Impact of Tocopherol Supplementation on Clinical Parameters of Periodontal Disease: A Systematic Review and Meta-Analysis

Background and Objectives: The significance of periodontal disease as a public health issue prompts the exploration of effective treatments, including the potential use of tocopherol (Vitamin E) due to its anti-inflammatory and antioxidant properties. Materials and Methods: The PICO statement (Population, Intervention, Comparator, Outcome) was as follows: In patients with periodontal disease, does tocopherol (Vitamin E) supplementation compared to no supplementation or insufficient Vitamin E intake improve clinical outcomes such as gingival inflammation, pocket depth, and clinical attachment levels? This study searched through PubMed, Scopus, and Web of Science up to June 2024 focused on studies involving human subjects with various forms of periodontal disease, analyzing the impact of tocopherol through dietary or supplementary intake. Primary outcomes evaluated included improvements in gingival inflammation, pocket depth, and clinical attachment levels, with data synthesis conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Quality assessment and risk of bias were meticulously performed for the included observational studies and randomized controlled trials. Results: The meta-analysis incorporated 8 studies that were used for data extraction, totaling 12,832 patients, revealing a heterogeneous response to tocopherol supplementation, with a pooled odds ratio for efficacy in reducing periodontal disease severity at about 0.97 (95% CI: 0.96-0.98). Noteworthy findings indicated a statistically significant increase in clinical attachment loss and pocket depth with odds ratios ranging from 1.15 to 9.33 when Vitamin E was insufficient. However, the considerable heterogeneity (I2 = 88.35%) underscores variations in tocopherol's effectiveness across different populations and study designs. Conclusions: While tocopherol supplementation shows a modest benefit in managing periodontal disease, particularly in reducing clinical attachment levels and pocket depth, the variability in outcomes emphasizes the necessity for more research to establish standardized treatment protocols and dosages.

Akkermansia muciniphila as a Potential Guardian against Oral Health Diseases: A Narrative Review

The oral microbiome is a diverse ecosystem containing a community of symbiotic, commensal, and pathogenic microorganisms. One key microorganism linked to periodontal disease (PD) is Porphyromonas gingivalis (P. gingivalis), a Gram-negative anaerobic bacterium known to have several virulence factors that trigger inflammation and immune evasion. On the other hand, Akkermansia muciniphila (A. muciniphila), a symbiotic bacterium, has been recently shown to play an important role in mitigating inflammation and reducing periodontal damage. In vivo and in vitro studies have shown that A. muciniphila decreases inflammatory mediators and improves immune responses, suggesting its role in mitigating PD and related inflammatory systemic conditions such as diabetes, hypertension, and obesity. This review discusses the anti-inflammatory effects of A. muciniphila, its impact on periodontal health, and its potential role in managing systemic diseases. The overall aim is to elucidate how this bacterium might help reduce inflammation, improve oral health, and influence broader health outcomes.

Local Drug Delivery Systems as Novel Approach for Controlling NETosis in Periodontitis

Periodontitis is a chronic inflammation caused by periodontopathogenic bacteria in the dental biofilm, and also involves the inflammatory-immune response of the host. Polymorphonuclear neutrophils (PMNs) play essential roles in bacterial clearance by multiple mechanisms, including the formation of neutrophil extracellular traps (NETs) that retain and destroy pathogens. During PD progression, the interaction between PMNs, NETs, and bacteria leads to an exaggerated immune response and a prolonged inflammatory state. As a lesion matures, PMNs accumulate in the periodontal tissues and die via NETosis, ultimately resulting in tissue injury. A better understanding of the role of NETs, the associated molecules, and the pathogenic pathways of NET formation in periodontitis, could provide markers of NETosis as reliable diagnostic and prognostic tools. Moreover, an assessment of NET biomarker levels in biofluids, particularly in saliva or gingival crevicular fluid, could be useful for monitoring periodontitis progression and treatment efficacy. Preventing excessive NET accumulation in periodontal tissues, by both controlling NETs' formation and their appropriate removal, could be a key for further development of more efficient therapeutic approaches. In periodontal therapy, local drug delivery (LDD) systems are more targeted, enhancing the bioavailability of active pharmacological agents in the periodontal pocket and surrounding tissues for prolonged time to ensure an optimal therapeutic outcome.

The Effect of Periodontitis on Body Size Phenotypes in Adults without Diagnosed Chronic Diseases: The Korean National Health and Nutrition Examination Survey 2013-2015

We aimed to examine the correlation between periodontitis and body size phenotypes in 7301 participants without diagnosed chronic diseases in the Korean National Health and Nutrition Examination Survey 2013-2015. The participants were categorized into the following body size phenotype groups based on body mass index and the presence of metabolic syndrome: metabolically healthy normal weight (MHNW), metabolically abnormal normal weight (MANW), metabolically healthy obese (MHO), and metabolically abnormal obese (MAO). The prevalence rates of mild and severe periodontitis were 18.1% and 7.5%, respectively. Patients with periodontitis were older, current smokers, had a lower family income, were less likely to engage in regular tooth brushing or exercise, and had a higher body mass index and glucose levels. Periodontitis was more prevalent in the MANW and MAO groups than in the MHNW and MHO groups. Compared with the MHNW phenotype, the MAO and MANW phenotypes were significantly associated with mild and severe periodontitis, and the MHO phenotype was significantly associated with mild periodontitis. The MANW and MAO phenotypes are independent risk factors for periodontitis in adults without diagnosed chronic diseases. To enhance public health, a greater focus and effective approaches for identifying metabolic disease phenotypes among individuals with periodontal disease may be clinically relevant.

Oral Microbiome Dysbiosis as a Risk Factor for Stroke: A Comprehensive Review

Stroke represents a significant global health burden, with a substantial impact on mortality, morbidity, and long-term disability. The examination of stroke biomarkers, particularly the oral microbiome, offers a promising avenue for advancing our understanding of the factors that contribute to stroke risk and for developing strategies to mitigate that risk. This review highlights the significant correlations between oral diseases, such as periodontitis and caries, and the onset of stroke. Periodontal pathogens within the oral microbiome have been identified as a contributing factor in the exacerbation of risk factors for stroke, including obesity, dyslipidemia, atherosclerosis, hypertension, and endothelial dysfunction. The alteration of the oral microbiome may contribute to these conditions, emphasizing the vital role of oral health in the prevention of cardiovascular disease. The integration of dental and medical health practices represents a promising avenue for enhancing stroke prevention efforts and improving patient outcomes.

Interlinked Pathways: Exploring the Bidirectional Impacts of Periodontitis and Metabolic Syndrome

Metabolic syndrome (MBS) and periodontitis are distinct conditions with overlapping and unique risk factors. Periodontitis is a chronic destructive disease of the periodontium, driven by alterations in the host immune-inflammatory response to virulent periodontal pathogens. MBS is characterized by various abnormalities, including visceral abdominal obesity, dyslipidemia (low high-density lipoprotein (HDL) and high triglyceride (TG) levels), hypertension, and hyperglycemia. These factors collectively increase the risk of atherosclerotic cardiovascular disease (CVD) and diabetes. Several pro-inflammatory mediators are involved in the pathogenesis of periodontitis and MBS, and the deleterious bidirectional effects of these mediators exacerbate the severity and progression of both conditions. This comprehensive review focuses on the intricate relationship between MBS and periodontitis. Specifically, it explores the pathophysiological mechanisms of each disease component of MBS and its impact on periodontitis, and vice versa.

Associations between different triglyceride glucose index-related obesity indices and periodontitis: results from NHANES 2009-2014

BACKGROUND

This study aimed to explore the associations between triglyceride glucose (TyG) index-related obesity indices and periodontitis within the American population.

METHODS

This cross-sectional investigation utilized data from the National Health and Nutrition Examination Survey (NHANES) for 2009-2014. The association between the TyG-waist-to-height ratio (TyG-WHtR), TyG-weight-adjusted-waist index (TyG-WWI), TyG-waist circumference (TyG-WC), or TyG-body mass index (TyG-BMI) and periodontitis was investigated utilizing multivariable logistic regression model, subgroup, and dose-response curve analyses.

RESULTS

This study enrolled 4,808 adult participants. Except for TyG-BMI, which did not exhibit a relationship with periodontitis, TyG-WHtR, [odds ratio (OR) (95% confidence interval (CI))] = 2.83 [1.58-5.10], P = 0.002], TyG-WWI [OR (95% CI) = 7.50 (3.06-18.34), P < 0.001], and TyG-WC [OR (95% CI) = 2.12 (1.23-3.64), P = 0.011] were all associated with periodontitis. Participants in the highest quartile displayed an elevated risk of periodontitis relative to their counterparts in the lowest quartile, as evidenced for TyG-WWI [OR (95% CI) = 1.72 (1.26-2.33), P = 0.001] and TyG-WC [OR (95% CI) = 1.50 (1.13-1.99), P = 0.009] in the full adjustment model. Subgroup analyses suggested more pronounced positive associations between these indices and periodontitis in participants who were < 60 years old, had a BMI ≥ 25, and did not have diabetes. The dose-response curve indicated linear responses in these associations.

CONCLUSIONS

This investigation identified a significant and stable association between TyG-WHtR, TyG-WWI, or TyG-WC and periodontitis, which implies a robust correlation between high insulin resistance and susceptibility to periodontitis in the American population.

Influence of METTL3 knockdown on PDLSC osteogenesis in E. coli LPS-induced inflammation

OBJECTIVE

This study aimed to investigate the effect of METTL3 knockdown on osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) in the weak inflammation microenvironments, as well as the underlying mechanisms.

MATERIALS AND METHODS

PDLSCs were stimulated by lipopolysaccharide from Escherichia coli (E. coli LPS), followed by quantification of METTL3. METTL3 expression was assessed using RT-qPCR and Western blot analysis in periodontitis. METTL3 knockdown PDLSCs were stimulated with or without E. coli LPS. The evaluation included proinflammatory cytokines, osteogenic markers, ALP activity, and mineralized nodules. Bioinformatics analysis and Western blot determined the association between METTL3 and the PI3K/Akt pathway.

RESULTS

METTL3 was overexpressed in periodontitis. METTL3 knockdown in PDLSCs reduced proinflammatory cytokines, osteogenic markers, ALP activity, and mineralized nodules in both environments. Bioinformatics analysis suggested a link between METTL3 and the PI3K/Akt pathway. METTL3 knockdown inhibited PI3K/Akt signaling pathway activation.

CONCLUSION

METTL3 knockdown might inhibit osteogenesis in PDLSCs through the inactivation of PI3K/Akt signaling pathway. Concomitant findings might shed novel light on the roles and potential mechanisms of METTL3 in the LPS-stimulated inflammatory microenvironments of PDLSCs.

Expression of advanced glycation end products and their receptors in diabetic periodontitis patients

AIM

The systematic review aimed to compare the levels of advanced glycation end products (AGEs) and RAGE (AGE receptors) expression in diabetic periodontitis patients with non-diabetic periodontitis patients and to identify the relationship of AGE and RAGE levels with periodontal disease severity.

MATERIALS AND METHODS

The literature search was carried out according to PRISMA guidelines by two independent researchers using four online databases: PubMed, Scopus, Web of Science Core Collection, and Pro-Quest. Relevant studies published between 2000 and March 2023 were included in this review. The association of diabetes and AGE/RAGE levels on periodontal health, periodontal pocket depth (PPD), and clinical attachment loss (CAL) was studied.

RESULTS

Sixteen cross-sectional studies, including 2794 patients (age range 15-75 years), were identified in the final stage. An elevated AGE level was observed among patients with diabetes and chronic periodontal disease compared to the non-diabetic group. Furthermore, the levels of AGE and RAGE are associated with CAL and PPD. Potential confounding factors like genetic and methodological differences were also responsible for AGE and RAGE variation.

CONCLUSION

Levels of AGEs and RAGE expressions in diabetic periodontitis patients differ from non-diabetic periodontitis patients. The differences may impact the course and severity of periodontal disease.

Insight of the interrelationship and association mechanism between periodontitis and diabetes mellitus

Periodontitis and diabetes mellitus are two prevalent chronic diseases that have been recognized to exhibit a bidirectional relationship. Individuals with diabetes are more susceptible to periodontitis, and conversely, periodontitis can exacerbate glycemic control in diabetic patients. The underlying mechanisms of this interrelationship involve complex pathways, including inflammatory responses, altered immune functions, and microbial dysbiosis. The mechanistic insights into the interrelationship between periodontitis and diabetes mellitus revolve around the role of inflammation as a common link between the two diseases. Inflammatory mediators such as cytokines, chemokines, and prostaglandins play a crucial role in the pathogenesis and progression of the diseases. The dysregulation of the immune response in diabetes can exacerbate the inflammatory response in periodontitis, leading to increased tissue destruction and bone resorption. The chronic inflammation in periodontitis can contribute to insulin resistance and impaired glycemic control in diabetic patients. Future directions in research aim to further elucidate the molecular mechanisms underlying the interrelationship between periodontitis and diabetes mellitus. Modulating the inflammatory response, restoring microbial balance, and improving glycemic control hold promise in managing both conditions simultaneously. Herein, we will provide an overview of the interrelationship of periodontitis and diabetes mellitus, and retrospect the underlying mechanisms, which may inspire investigators with further research directions.

Assessing Causal Relationships Between Periodontitis and Non-alcoholic Fatty Liver Disease: A Two-Sample Bidirectional Mendelian Randomisation Study

PURPOSE

To investigate the causality between periodontitis and non-alcoholic fatty liver disease (NAFLD) using a two-sample bidirectional Mendelian randomisation (MR) analysis.

MATERIALS AND METHODS

Genetic variations in periodontitis and NAFLD were acquired from genome-wide association studies (GWAS) using the Gene-Lifestyle Interaction in Dental Endpoints, a large-scale meta-analysis, and FinnGen consortia. Data from the first two databases were used to explore the causal relationship between periodontitis and NAFLD ("discovery stage"), and the data from FinnGen was used to validate our results ("validation stage"). We initially performed MR analysis using 5 single nucleotide polymorphisms (SNPs) in the discovery samples and 18 in the replicate samples as genetic instruments for periodontitis to investigate the causative impact of periodontitis on NAFLD. We then conducted a reverse MR analysis using 6 SNPs in the discovery samples and 4 in the replicate samples as genetic instruments for NAFLD to assess the causative impact of NAFLD on periodontitis. We further implemented heterogeneity and sensitivity analyses to assess the reliability of the MR results.

RESULTS

Periodontitis was not causally related to NAFLD (odds ratio [OR] = 1.036, 95% CI: 0.914-1.175, p = 0.578 in the discovery stage; OR = 1.070, 95% CI: 0.935-1.224, p = 0.327 in the validation stage), and NAFLD was not causally linked with periodontitis (OR = 1.059, 95% CI: 0.916-1.225, p = 0.439 in the discovery stage; OR = 0.993, 95% CI: 0.896-1.102, p = 0.901 in the validation stage). No heterogeneity was observed among the selected SNPs. Sensitivity analyses demonstrated the absence of pleiotropy and the reliability of our MR results.

CONCLUSION

The present MR analysis showed no genetic evidence for a cause-and-effect relationship between periodontitis and NAFLD. Periodontitis may not directly influence the development of NAFLD and vice versa.

The role of periodontitis in the development of atherosclerotic cardiovascular disease in participants with the components of metabolic syndrome: a systematic review and meta-analysis

OBJECTIVES

Prevention of atherosclerotic cardiovascular disease (ASCVD) is important in individuals with metabolic syndrome components (MetS), and periodontitis may play an important role in this process. This study aims to evaluate the association between periodontitis and ASCVD in participants with the components of MetS, including obesity, dysglycemia, hypertension, and dyslipidemia.

MATERIALS AND METHODS

This study conducted followed the MOOSE reporting guidelines and the PRISMA 2020 guidelines. EMBASE, MEDLINE, Web of Science, Cochrane Library, PubMed and OpenGrey were searched for observational studies about the linkage of periodontitis to ASCVD in people with MetS components up to April 9, 2023. Cohort, case-control and cross-sectional studies were included after study selection. Quality evaluation was carried out using the original and modified Newcastle-Ottawa Scale as appropriate. Random-effects model was employed for meta-analysis.

RESULTS

Nineteen studies were finally included in the quality analysis, and all of them were assessed as moderate to high quality. Meta-analyses among fifteen studies revealed that the participants with periodontitis were more likely to develop ASCVD in those who have dysglycemia (RR = 1.25, 95% CI = 1.13-1.37; p < 0.05), obesity (RR = 1.13, 95% CI = 1.02-1.24; p < 0.05), dyslipidemia (RR = 1.36, 95% CI = 1.13-1.65; p < 0.05), or hypertension (1.20, 95% CI = 1.05-1.36; p < 0.05).

CONCLUSIONS

Periodontitis promotes the development of ASCVD in participants with one MetS component (obesity, dysglycemia, hypertension or dyslipidemia).

CLINICAL RELEVANCE

In people with MetS components, periodontitis may contribute to the ASCVD incidence.

Association of carotid intima-media thickness with periodontitis may depend on glycemic control

BACKGROUND

There is evidence indicating that atherosclerosis is associated with periodontitis, especially in those with diabetes. The purpose of the present study was to determine whether glycemic control influences such association.

METHODS

Cross-sectional data on 214 patients diagnosed with type 2 diabetes mellitus were obtained including results of basic laboratory tests, a periodontal examination, and carotid measurements. The association of periodontal parameters and carotid intima-media thickness (cIMT) or carotid plaque (CP) was evaluated in subgroups.

RESULTS

Mean cIMT was significantly correlated with mean PLI, mean BI or number of PD ≥4 mm in the whole sample and the group with poor glycemic control. In the group with good glycemic control, however, only the number of PD ≥4 mm was associated with mean cIMT. A multiple logistic regression analysis also revealed that each 1 increase in mean PLI, mean BI or number of PD ≥4 mm was correlated with an increased cIMT in the whole sample.

CONCLUSIONS

In addition to confirming the relationship between periodontitis and atherosclerosis, our study found a stronger association in groups with poor glycemic control compared to those with good glycemic control, suggesting that blood glucose modifies the association between periodontitis and arterial injury.

The impact of different states of type 2 diabetes when stratified by baseline HbA1c on the periodontal outcomes of non-surgical periodontal treatment: A systematic review and network meta-analysis

BACKGROUND

Type 2 diabetes mellitus (T2DM) has been considered by many studies to have a bidirectional relationship with periodontitis. This systematic review and network meta-analysis aimed to investigate the impact of different states of T2DM when stratified by baseline HbA1c on the clinical outcomes of non-surgical periodontal treatment (NSPT).

METHODS

This study followed the Preferred Reporting Items for Meta-Analyses (PRISMA) guidelines and involved an electronic literature search (from inception to the 2nd of January 2023). The study included at least two groups of patients: chronic periodontitis only (No-DM) or periodontitis and well-controlled/poorly controlled type 2 diabetes mellitus (WC/PC-T2DM). Clinical outcomes included probing depth (PD) reduction, bleeding on probing reduction, and clinical attachment level (CAL) gain. Direct and indirect comparisons between groups were assessed by network meta-analysis, thus allowing us to establish a treatment ranking.

RESULTS

Ten prospective cohort studies (11 data sets) were included for qualitative analysis and network meta-analysis. The data included in this study had high consistency; in addition, a funnel plot and Egger's test showed that the articles had low publication bias. Network meta-analysis showed that the effect of NSPT in the No-DM group was significantly better than the WC-T2DM group [weighted mean difference (WMD) = 0.09, 95% confidence interval (CI) (0.01, 0.18)] and the PC-T2DM group [WMD = 0.09, 95% CI (0.01, 0.18)] in terms of CAL gain and better than the PC-T2DM group [WMD = 0.15, 95% CI (0.02, 0.28)] in terms of PD reduction. According to the surface under the cumulative ranking value, the No-DM group had the highest probability of achieving the best outcome following NSPT.

CONCLUSIONS

Collectively, our analyses show that T2DM exerts significant effects on the outcomes of NSPT.

Does Full-Mouth Disinfection Influence the Size of the Periodontal Inflammatory Burden and the Level of hsCRP?

PURPOSE

To investigate the effect of full-mouth disinfection on the sizes of the periodontal wound and periodontal inflammatory burden and whether it leads to a decrease in C-reactive protein (CRP) levels.

MATERIALS AND METHODS

The study included 20 systemically healthy subjects (11 women and 9 men) 30 to 68 years old with localised or generalised periodontitis (stage III, grade C). The sizes of the periodontal wound and periodontal inflammatory burden were measured with the web application "Periodontalwound", which is based on measurements of average tooth cervices, as well as probing depths and bleeding on probing assessed at six sites around each tooth present in the oral cavity. The levels of hsCRP (high-sensitivity CRP) were measured with an immunochemical method. All three parameters were measured before initial treatment and 3 months after therapy. Full-mouth disinfection included removal of plaque and calculus with ultrasonic and hand instruments in one session.

RESULTS

The results showed a statistically significant decrease in the size of the periodontal wound (p < 0.001), a statistically significant decrease in the size of periodontal inflammatory burden (p < 0.001), and a decrease in hsCRP levels 3 months after therapy.

CONCLUSION

Full-mouth disinfection leads to a decrease in the periodontal wound and periodontal inflammatory burden size, as well as a decrease in the levels of hsCRP in patients with localised or generalised periodontitis (stage III, grade C).

Association between dental scaling and metabolic syndrome and lifestyle

PURPOSE

Periodontal disease is a risk factor for diabetes and metabolic syndrome, and non-surgical periodontal treatment has been shown to help maintain stable blood sugar in diabetic patients. Determining the level of preventive scaling in patients with metabolic syndrome will help manage the disease. The purpose of this study was to investigate the extent to which people with metabolic syndrome or bad lifestyle performed scaling and the association between preventive scaling and metabolic syndrome or lifestyle in a large population.

METHODS

This study was conducted on adults aged 20 years or older from January 2014 to December 2017 in the National Health Insurance System (NHIS) database. Among 558,067 people who underwent health checkups, 555,929 people were included. A total of 543,791 people were investigated for preventive scaling. Metabolic syndrome components were abdominal obesity, lower high density lipoprotein cholesterol (HDL)-C, high triglycerides, high blood pressure and hyperglycemia. Unhealthy lifestyle score was calculated by assigning 1 point each for current smokers, drinkers, and no performing regular exercise.

RESULTS

When multiple logistic regression analysis was performed after adjusting for age, sex, income, body mass index (BMI), smoking, drinking and regular exercise, the Odds ratios (OR) and 95% confidence intervals (CI) of the group with 5 metabolic syndrome components were 0.741 (0.710, 0.773) (p<0.0001). After adjustment for age, sex, income, BMI, smoking, drinking, regular exercise, diabetes, hypertension and dyslipidemia, the OR (95% CI) of the group with unhealthy lifestyle score = 3 was 0.612 (0.586, 0.640) (p<0.0001).

CONCLUSIONS

The more metabolic syndrome components, and the higher unhealthy lifestyle score, the less scaling was performed.

Association between vitamin D levels and risk of periodontitis in patients with metabolic syndrome

Background/purpose

The relationship between Vitamin D (VD) and periodontitis in patients with metabolic syndrome (MetS) was unclear. This study was to investigate the relationship between VD and periodontitis in MetS patients.

Materials and methods

This cross-sectional study collected the data of 2165 MetS patients from the National Health and Nutrition Examination Survey (NHANES). The weighted univariate and multivariable Logistic regression models were applied to identify covariates and evaluate the association between 25-hydroxy vitamin D (25(OH)D) [25(OH)D]2 + 25(OH)D3 and periodontitis in patients. Odds ratio (OR) [95% confidence interval (CI)] was effect size. Subgroup analysis was performed in people with or without diabetes, dyslipidemia, hypertension, cardiovascular disease (CVD) and central obesity groups.

Results

In the unadjusted model, compared with patients with 25(OH)D2 + 25(OH)D3 < 50 nmol/L, those with 25(OH)D2 + 25(OH)D3 ≥ 50 nmol/L might be associated with decreased risk of periodontitis in MetS patients (OR = 0.70, 95% CI: 0.57-0.85). After adjusting for confounders including age, gender, race, education, poverty income ratio (PIR), smoking, diabetes, VD intake and supplement and number of missing teeth, 25(OH)D2 + 25(OH)D3 ≥ 50 nmol/L was correlated with reduced risk of periodontitis in MetS patients (OR = 0.76, 95% CI: 0.60-0.97). Subgroup analysis revealed that in patients with CVD (OR = 0.60, 95% CI: 0.37-0.98), dyslipidemia (OR = 0.75, 95% CI: 0.57-0.97), and patients with central obesity (OR = 0.73, 95% CI: 0.57-0.95), decreased risk of periodontitis was identified in 25(OH)D2 + 25(OH)D3 ≥ 50 nmol/L.

Conclusion

VD was associated with the risk of periodontitis in patients with MetS, which suggest the importance of VD supplement in patients with MetS and provide a reference for the management of periodontitis in patients with MetS.

Comparing the activity level of salivary matrix metalloproteinase-8 in patients with diabetes and moderate to severe chronic generalized periodontitis

OBJECTIVES

The response of the host to plaque can be affected by systemic diseases like diabetes, hormonal changes, or immunological deficits, which can hasten the progression and severity of periodontitis. This study aimed to compare the activity of salivary matrix metalloproteinase-8 (MMP-8) in patients with moderate to severe generalized chronic generalized periodontitis between healthy individuals and those with type 2 diabetes who were referred to the Tabriz School of Dentistry.

MATERIALS AND METHODS

For this cross-sectional study, 90 patients were randomly divided into three groups based on inclusion and exclusion criteria: patients with chronic generalized periodontitis with diabetes, patients with generalized chronic periodontal disease with normal blood glucose, and a control group of 30 healthy individuals. Participants were instructed not to brush their teeth for 12 h and not to eat or drink for 90 min before saliva sampling. Saliva samples were immediately stored at -80°C and analyzed using an ELISA test.

RESULTS

The results showed that there was a significant difference in salivary MMP-8 levels among the three groups. Patients with periodontitis and diabetes had the highest levels of salivary MMP-8, while the control group had the lowest levels. This indicates that chronic generalized periodontitis is strongly associated with the activity level of salivary MMP-8, and elevated levels of MMP-8 in diabetic patients demonstrate the impact of diabetes on periodontal disease.

CONCLUSION

This study highlights the importance of monitoring salivary MMP-8 levels in patients with periodontitis, especially those with diabetes. It also emphasizes the need for proper management of systemic diseases to prevent or slow down the progression of periodontal disease.

The impact of metabolic disorders on management of periodontal health in children

Periodontitis is a chronic inflammatory disease caused by plaque biofilm which shares risk factors with systemic chronic diseases such as diabetes, cardiovascular disease, and osteoporosis. Many studies have found increased prevalence and rate of progression of periodontal disease in children with common metabolic disorders. Although the causal relationship and specific mechanism between them has not been determined yet. The aim of this paper is to progress on the impact of metabolic disorders on periodontal health in children and the underlying mechanisms, which provides new evidences for the prevention and intervention of metabolic disorders and periodontitis in children.

Effects of Metabolic Syndrome and its components on the postoperative recurrence in Chronic Rhinosinusitis with Nasal Polyps' patients

OBJECTIVES

Metabolic Syndrome (MetS) has been established as a significant factor in the pathogenesis of numerous chronic inflammatory conditions. However, its role in Chronic Rhinosinusitis with Nasal Polyps (CRSwNP) is unknown. This study aims to investigate the association between MetS, its components, and the risk of postoperative recurrence in Chinese patients with CRSwNP.

METHODS

A retrospective cohort study was conducted on CRSwNP patients who underwent endoscopic sinus surgery in our hospital. Patients were divided into MetS and non-MetS groups, and the clinical characteristics and recurrence rates were compared. All CRSwNP patients were followed up for more than 2-years and further categorized into non-recurrent and recurrent groups. Binary logistic regression analyses were performed to examine the effects of MetS and its components on the risk of postoperative recurrence.

RESULTS

A total of 555 CRSwNP patients were enrolled in the present study, 157 patients were included in the MetS group and 398 patients were categorized into the non-MetS group. The recurrence rate in the MetS group was significantly higher compared to the non-MetS group (p < 0.05). The rate of MetS, overweight or obesity, hyperglycemia and dyslipidemia were higher in the recurrent group in comparison with the non-recurrent group (p < 0.05). Multivariate logistic regression analysis suggested that MetS, overweight or obesity, hyperglycemia, dyslipidemia, and accompanying allergic rhinitis were associated with the risk of postoperative recurrence of CRSwNP (p < 0.05). Moreover, adjusted and unadjusted regression models showed that MetS was an independent risk factor for postoperative recurrence of CRSwNP, and the risk increased with more components of MetS included (p < 0.05).

CONCLUSION

Our findings revealed that MetS independently increased the risk of postoperative recurrence in patients with CRSwNP, with the risk escalating as the number of MetS components increased. Moreover, accompanying allergic rhinitis was also demonstrated to be a potential risk factor for CRSwNP recurrence.

LEVEL OF EVIDENCE

Level 4.

Sex differences in the association between dual-energy x-ray absorptiometry-measured body composition and periodontitis

BACKGROUND

A positive association between obesity based on body mass index (BMI) and periodontitis has been reported. Fat tissue-related systemic inflammation acts as the link to periodontal comorbidities of obesity. However, the BMI is unable to distinguish fat and fat-free tissues. More precise measures are required to evaluate body composition, including fat and fat-free tissues. This study aimed to determine the sex differences in the association between dual-energy x-ray absorptiometry (DXA)-measured body composition (i.e., fat mass and muscle mass) and phenotypes with periodontitis.

METHODS

Cross-sectional data of 3892 participants from the National Health and Nutrition Examination Survey (NHANES) study 2011‒2014 were analyzed. Adiposity indices (fat mass index [FMI] and percentage body fat [%BF]) and muscle mass index (MMI) were calculated. The participants were categorized by the quintiles of FMI, MMI, and %BF. Body composition phenotypes were categorized as: low adiposity-low muscle (LA-LM), low adiposity-high muscle (LA-HM), high adiposity-low muscle (HA-LM), or high adiposity-high muscle (HA-HM), respectively. Periodontitis was defined by the CDC/AAP (Centers for Disease Control and Prevention/American Academy of Periodontology) criteria. Multivariable logistic regression analysis was conducted, stratified by sex. We further adjusted for white blood cell (WBC) counts in the sensitivity analysis.

RESULTS

Restricted cubic splines revealed non-linear associations between body composition indices and periodontitis risk. Women with a higher FMI (odds ratio for Q5 vs. Q1 [ORQ5vs1] = 1.787, 95% confidence interval: 1.209-2.640) or %BF (ORQ5vs1 = 2.221, 1.509-3.268) had increased odds of periodontitis. In addition, women with HA-LM phenotype were more likely to develop periodontitis (OR = 1.528, 1.037-2.252). Interestingly, the WBC count, a systemic inflammatory biomarker, attenuated these associations. No statistically significant associations were found in men.

CONCLUSIONS

The association between DXA-measured body composition and phenotypes with periodontitis differs per sex. Only in women higher adiposity indices and HA-LM phenotype were associated with an increased risk of periodontitis.

Periodontal and Systemic Diseases: A Descriptive Analysis of Awareness Among the General Saudi Population

Background Taking into account the limited availability of research data, this study aimed to determine the general Saudi population's awareness of the link between periodontal diseases and systemic diseases. Methodology A structured online questionnaire with eight awareness items, apart from demographic variables, was distributed through email, WhatsApp, and Telegram to a sample of 500 individuals. The data were analyzed using a simple descriptive statistical approach and interpreted as ratios for comparison. The awareness regarding systemic diseases associated with periodontal diseases was classified into the following four categories based on the Bloom cutoff points: high (>80%), average (60-79%), low (40-59%), and extremely low (<40%). Results A response rate of 68% was reached with the participation of 340 Saudi citizens residing in the Al Qassim region. Overall, 61.22% of research participants had an average awareness of the link between periodontal and systemic diseases. Almost two-thirds (>60%) of participants were aware that periodontal diseases and systemic diseases have an association and that individuals with systemic diseases need a periodontal checkup. A majority (85%) of participants opined that periodontal treatment has the potential to enhance overall health. Nonetheless, only a few participants (60%) were aware of the association between diabetes mellitus and periodontal diseases, and they had a limited awareness of the association with other systemic diseases. Conclusions Although the Saudi general population possesses average awareness about the relationship between periodontal diseases and systemic diseases, their awareness about different systemic diseases and conditions is extremely low, particularly regarding infertility, stroke, and metabolic diseases. The present research indicates a deficiency in the efforts by healthcare professionals, community service providers, and community administrators to educate the general public regarding the association between periodontal diseases and systemic diseases. This awareness is crucial for individuals to control these intricate, interconnected diseases.

PINK1 dominated mitochondria associated genes signature predicts abdominal aortic aneurysm with metabolic syndrome

Abdominal aortic aneurysm (AAA) is typically asymptomatic but a devastating cardiovascular disorder, with overall mortality exceeding 80 % once it ruptures. Some patients with AAA may also have comorbid metabolic syndrome (MS), suggesting a potential common underlying pathogenesis. Mitochondrial dysfunction has been reported as a key factor contributing to the deterioration of both AAA and MS. However, the intricate interplay between metabolism and mitochondrial function, both contributing to the development of AAA, has not been thoroughly explored. In this study, we identified candidate genes related to mitochondrial function in AAA and MS. Subsequently, we developed a nomoscore model comprising hub genes (PINK1, ACSL1, CYP27A1, and SLC25A11), identified through the application of two machine learning algorithms, to predict AAA. We observed a marked disparity in immune infiltration profiles between high- and low-nomoscore groups. Furthermore, we confirmed a significant upregulation of the expression of the four hub genes in AAA tissues. Among these, ACSL1 showed relatively higher expression in LPS-treated RAW264.7 cell lines, while CYP27A1 exhibited a notable decrease. Moreover, SLC25A11 displayed a significant upregulation in AngII-treated VSMCs. Conversely, the expression level of PINK1 declined in LPS-stimulated RAW264.7 cell lines but significantly increased in AngII-treated VSMCs. In vivo experiments revealed that the activation of PINK1-mediated mitophagy inhibited the development of AAA in mice. In this current study, we have innovatively identified four mitochondrial function-related genes through integrated bioinformatic analysis. This discovery sheds light on the regulatory mechanisms and unveils promising therapeutic targets for the comorbidity of AAA and MS.

COVID-19 associated oral and oropharyngeal microbiome: Systematic review and meta-analysis

Three years into the coronavirus disease 2019 (COVID-19) pandemic, there are still growing concerns with the emergence of different variants, unknown long- and short-term effects of the virus, and potential biological mechanisms underlying etiopathogenesis and increased risk for morbidity and mortality. The role of the microbiome in human physiology and the initiation and progression of several oral and systemic diseases have been actively studied in the past decade. With the proof of viral transmission, carriage, and a potential role in etiopathogenesis, saliva and the oral environment have been a focus of COVID-19 research beyond diagnostic purposes. The oral environment hosts diverse microbial communities and contributes to human oral and systemic health. Several investigations have identified disruptions in the oral microbiome in COVID-19 patients. However, all these studies are cross-sectional in nature and present heterogeneity in study design, techniques, and analysis. Therefore, in this undertaking, we (a) systematically reviewed the current literature associating COVID-19 with changes in the microbiome; (b) performed a re-analysis of publicly available data as a means to standardize the analysis, and (c) reported alterations in the microbial characteristics in COVID-19 patients compared to negative controls. Overall, we identified that COVID-19 is associated with oral microbial dysbiosis with significant reduction in diversity. However, alterations in specific bacterial members differed across the study. Re-analysis from our pipeline shed light on Neisseria as the potential key microbial member associated with COVID-19.

The role of mitophagy in metabolic diseases and its exercise intervention

Mitochondria are energy factories that sustain life activities in the body, and their dysfunction can cause various metabolic diseases that threaten human health. Mitophagy, an essential intracellular mitochondrial quality control mechanism, can maintain cellular and metabolic homeostasis by removing damaged mitochondria and participating in developing metabolic diseases. Research has confirmed that exercise can regulate mitophagy levels, thereby exerting protective metabolic effects in metabolic diseases. This article reviews the role of mitophagy in metabolic diseases, the effects of exercise on mitophagy, and the potential mechanisms of exercise-regulated mitophagy intervention in metabolic diseases, providing new insights for future basic and clinical research on exercise interventions to prevent and treat metabolic diseases.