Increased serum PCSK9, a potential biomarker to screen for periodontitis, and decreased total bilirubin associated with probing depth in a Japanese community survey

Integrative microbiome and metabolome profiles reveal the impacts of periodontitis via oral-gut axis in first-trimester pregnant women

BACKGROUND

Periodontitis results from host-microbe dysbiosis and the resultant dysregulated immunoinflammatory response. Importantly, it closely links to numerous systemic comorbidities, and perplexingly contributes to adverse pregnancy outcomes (APOs). Currently, there are limited studies on the distal consequences of periodontitis via oral-gut axis in pregnant women. This study investigated the integrative microbiome-metabolome profiles through multi-omics approaches in first-trimester pregnant women and explored the translational potentials.

METHODS

We collected samples of subgingival plaques, saliva, sera and stool from 54 Chinese pregnant women at the first trimester, including 31 maternal periodontitis (Perio) subjects and 23 Non-Perio controls. By integrating 16S rRNA sequencing, untargeted metabolomics and clinical traits, we explored the oral-gut microbial and metabolic connection resulting from periodontitis among early pregnant women.

RESULTS

We demonstrated a novel bacterial distinguisher Coprococcus from feces of periodontitis subjects in association with subgingival periodontopathogens, being different from other fecal genera in Lachnospiraceae family. The ratio of fecal Coprococcus to Lachnoclostridium could discriminate between Perio and Non-Perio groups as the ratio of subgingival Porphyromonas to Rothia did. Furthermore, there were differentially abundant fecal metabolic features pivotally enriched in periodontitis subjects like L-urobilin and kynurenic acid. We revealed a periodontitis-oriented integrative network cluster, which was centered with fecal Coprococcus and L-urobilin as well as serum triglyceride.

CONCLUSIONS

The current findings about the notable influence of periodontitis on fecal microbiota and metabolites in first-trimester pregnant women via oral-gut axis signify the importance and translational implications of preconceptional oral/periodontal healthcare for enhancing maternal wellbeing.

The effects of severe periodontitis on arterial stiffness using cardio-ankle vascular index in patients with type 2 diabetes

BACKGROUND AND OBJECTIVE

Arterial stiffness, which is a measure of the elasticity of the arteries, is also a risk factor for the development of cardiovascular diseases and its measurement is important for evaluating the atherosclerosis process. The purpose of this cross-sectional study to investigate whether severe periodontitis in short-term type 2 diabetes may be associated with increased cardio-ankle vascular index (CAVI) values specified for subclinical atherosclerosis risk.

METHODS

A total of 136 subjects, including 69 subjects with short-term type 2 diabetes (35 with severe periodontitis and 34 with periodontally healthy) and 67 systemically healthy subjects (32 with severe periodontitis and 35 with periodontally healthy) were enrolled to this study. Assessment of all participants included in this study in terms of arterial stiffness was determined by CAVI. Serum fasting plasma glucose (FPG), glycated haemoglobin (HbA1c), triglyceride (TRG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol (TC) and C-reactive protein (CRP) levels were calculated using standard methods. Full mouth periodontal measurements were recorded. Multiple linear regression analysis was performed to evaluate the relationship between periodontal parameters and mean CAVI values of the groups.

RESULTS

Mean CAVI levels were significantly higher in diabetic and periodontitis group compared to the other study groups (p < .05). In diabetes and periodontitis group, CAVI was showed positive correlations with CRP (r = .337, p = .048) and HbA1c (r = .442, p = .008). Also, positive significant correlations were found with probing depth (PD) and clinical attachment level (CAL) in the periodontitis groups. Multiple regression analysis revealed that CAL independently predicted CAVI levels in periodontitis groups (β = .433, p = .019 in diabetes and periodontitis groups and β = .57, p = .001 in systemically healthy and periodontitis group respectively).

CONCLUSION

This is the first study investigating the association between severe periodontitis and CAVI in patients with short-term diabetes. Our findings suggest that severe periodontitis may be an intermediate factor in the pathway between type 2 diabetes and cardiovascular disease by increasing the arterial stiffness.

Roles of PCSK9 in the Pathogenesis of Periodontal Disease

Proprotein convertase subtilisin/Kexin type 9 (PCSK9) inhibitors are FDA-approved drugs recommended for high-risk patients with LDL-cholesterol (LDL-c) levels ≥ 70 mg/dl. Several studies have also investigated the relationship between PCSK9 and periodontitis. Specifically, studies have investigated the association between periodontitis and periodontal PCSK9 levels in humans, and periodontium status in PCSK9-knockout versus wild-type mice. While a positive association between periodontitis and periodontal PCSK9 levels has been noted, the findings on the comparison of periodontium status between PCSK9-knockout and wild-type mice have been inconsistent. Different methodologies among these studies may explain this discrepancy. Future experimental studies on the impact of pharmacological PCSK9 inhibition on periodontal status as well as observational studies comparing periodontium status between patients receiving PCSK9 inhibitors and those receiving other lipid-lowering drugs will shed light on the role of PCSK9 in periodontal health and disease.

Biomarkers for diagnosis of stage III, grade C with molar incisor pattern periodontitis in children and young adults: a systematic review and meta-analysis

AIM

To explore the existing salivary, gingival crevicular fluid (GCF), blood, and serum biomarkers associated with grade C molar-incisor pattern (C/MIP) periodontitis in systemically healthy children and young adults.

MATERIALS AND METHODS

Cross-sectional, case-control, and cohort studies on stage III grade C periodontitis or former equivalent diagnosis with analysis of molecular biomarkers in saliva, GCF, blood, or serum were retrieved from six databases and screened based on the eligibility criteria. The risk of bias in included studies was evaluated. Meta-analysis was planned for biomarkers assessed using the same detection methods and sample type in at least two papers.

RESULTS

Out of 5621 studies identified at initial screening, 28 papers were included in the qualitative analysis of which 2 were eligible for meta-analysis for IgG in serum samples. Eighty-seven biomarkers were assessed with the majority being higher in cases than in controls. Only the meta-analysis of total serum IgG with low heterogeneity value revealed a significant increase in its levels in C/MIPs compared to controls (standardised mean difference: 1.08; 95% CI: 0.76, 1.40).

CONCLUSION

There is a paucity of data on biomarkers associated with molar-incisor pattern periodontitis. Although serum IgG levels are raised, other more specific biomarkers in saliva, GCF, and blood/serum may be promising but require further investigation.

Evaluation of serum and salivary PCSK9 and IL6 and its association with periodontal inflammation and atherosclerotic cardiovascular diseases

Background

and Purpose: The aim of this study was to assess, compare and correlate the ability of PCSK9 and IL6 as potential common serum and salivary biomarkers for stage III/IV periodontitis and the risk of developing atherosclerotic cardiovascular diseases.

Methods

76 patients were alloted into 4 groups consisting of subjects with clinically healthy periodontium and stage III/IV periodontitis with and without ACVD. Clinical parameters - PD, CAL, number of teeth, PI, mSBI, TC, Tg, HDL and LDL were recorded. Serum and saliva samples were obtained and subjected to ELISA for quantifying the biomarker levels.

Results

The level of these biomarkers was found to be the lowest (IL6 Serum: 21.92 ± 14.54, IL6 Saliva: 12.34 ± 7.72, PCSK9 Serum: 178.82 ± 35.07, PCSK9 Saliva: 80.82 ± 25.43) in group I and highest in group IV (IL6 Serum: 73.4 ± 24.86, IL6 Saliva: 37.66 ± 15.77, PCSK9 Serum: 346.54 ± 45.11, PCSK9 Saliva: 157.72 ± 43.28). The clinical parameters PI, mSBI, PPD, CAL, total number of teeth, TC, HDL and LDL showed a significant correlation with biomarkers PCSK9 and IL6.

Conclusion

This study features the elevation of serum and salivary PCSK9 and IL6 in periodontitis and ACVD. A triad of serum and salivary PCSK9 and IL6 along with the clinical markers of periodontal disease can relatively predict the future risk of developing ACVD.

Increased serum PCSK9 in patients with idiopathic pulmonary arterial hypertension: insights from inflammatory cytokines

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an important and major player in the pathophysiology of hypercholesterolemia and atherosclerosis. Recently, PCSK9 has been implicated in the pathogenesis of inflammatory diseases. Whether PCSK9 is involved in idiopathic pulmonary arterial hypertension (IPAH) remains unclear. This study aimed to investigate the relationship between PCSK9 and IPAH. Serum PCSK9, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1 β (IL-1β), and monocyte chemotactic protein-1 (MCP-1) were measured by enzyme linked immunosorbent assay. Transthoracic echocardiography was performed among 40 IPAH patients and 20 control subjects. Hemodynamic data were collected via right heart catheterization in patients with IPAH. Serum PCSK9, TNF-α, IL-6, IL-1β, and MCP-1 levels were significantly higher in IPAH patients than in control subjects (p < 0.001). Among enrolled IPAH patients, PCSK9 levels were higher in WHO-FC III/IV patients compared with those in WHO-FC I/II (p < 0.05), and were positively correlated with TNF-α, IL-6, MCP-1, N-Terminal pro-brain natriuretic peptide, pulmonary arterial systolic pressure (r = 0.653, p < 0.001), pulmonary arterial diastolic pressure (r = 0.466, p = 0.002), mean pulmonary arterial pressure (mPAP, r = 0.730, <0.001), pulmonary vascular resistance (r = 0.488, p = 0.001), and right ventricle diameter (r = 0.563, p < 0.001). In multiple regression analysis, mPAP was strongly associated with serum PCSK9 (β = 0.694, p < 0.001), independent of other variables. Receiver operating characteristic curve analysis showed the optimal cutoff value of serum PCSK9 concentration for predicting IPAH was 90.67 ng/ml, with a sensitivity of 90.0% and a specificity of 85.0%. In conclusion, IPAH patients had elevated serum PCSK9 levels which correlated the presence and severity of pulmonary hypertension. PCSK9 may be a novel potential therapeutic target.

The role of PCSK9 in infectious diseases

BACKGROUND

In recent years, many aspects of the physiological role of PCSK9 have been elucidated, particularly regarding its role in lipid metabolism, cardiovascular risk, and its role in innate immunity. Increasing evidence is available about the involvement of PCSK9 in the pathogenesis of viral infections, mainly HCV, and the regulation of host response to bacterial infections, primarily sepsis and septic shock. Moreover, the action of PCSK9 has been investigated as a crucial step in the pathogenesis of malaria infection and disease severity.

OBJECTIVE

This paper aims to review the available published literature on the role of PCSK9 in a wide array of infectious diseases.

CONCLUSION

Besides the ongoing investigation on PCSK9 inhibition among HIV-infected patients to treat HIV- and ART-related hyperlipidemia, preclinical studies indicate how PCSK9 is involved in reducing the replication of HCV. Interestingly, high plasmatic PCSK9 levels have been described in patients with sepsis. Moreover, a protective role of PCSK9 inhibition has also been proposed against dengue and SARS-CoV-2 viral infections. Finally, a loss of function in the PCSK9-encoding gene has been reported to reduce malaria infection mortality.

Impact of Matrix Metalloproteinase-9 during Periodontitis and Cardiovascular Diseases

Matrix metalloproteinase-9 (MMP-9) has been shown to play a key role in endothelial function and perhaps pivotal in the correlation between periodontal disease and cardiovascular disease (CVD). For the study, the impact of MMP-9 of periodontitis and CVD on serum and saliva concentrations was analyzed. For the study patients with periodontitis (n = 31), CVD (n = 31), periodontitis + CVD (n = 31), and healthy patients (n = 31) were enrolled. Clinical and demographic characteristics as well as serum and salivary MMP-9 were evaluated. MMP-9 concentrations in serum and saliva were statistically elevated in patients with CVD (p < 0.01) and in patients with periodontitis plus CVD (p < 0.001) compared to patients with periodontitis and healthy subjects. Multivariate regression analysis showed that c-reactive protein (hs-CRP) was the only significant predictor for MMP-9 serum (p < 0.001), whereas hs-CRP (p < 0.001) and total cholesterol (p = 0.029) were the statistically significant salivary MMP-9 predictors. This study evidenced that patients with CVD and periodontitis + CVD presented elevated MMP-9 concentrations in serum and saliva compared to patients with periodontitis and healthy subjects. Furthermore, hs-CRP was a negative predictor of serum and salivary MMP-9.

A review of T helper 17 cell-related cytokines in serum and saliva in periodontitis

Periodontitis is a chronic inflammatory disease with a complex underlying immunopathology. Cytokines, as molecular mediators of inflammation, play a role in all stages of disease progression. T helper 17 (Th17) cells are thought to play a role in periodontitis. Th17 cell development and maintenance requires a pro-inflammatory cytokine milieu, with many of the cytokines implicated in the pathogenesis of periodontitis. Serum and saliva are easily accessible biofluids which can represent the systemic and local environment to promote the development of Th17 cells. Here we review human clinical studies that investigate IL-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, IFN-γ, sCD40L and TNF-α in serum and saliva in periodontitis. We highlight their putative role in the pathogenesis of periodontitis and place them within a wider context of animal and other clinical studies.

β 2-Microglobulin and Neutrophil Gelatinase-Associated Lipocalin, Potential Novel Urine Biomarkers in Periodontitis: A Cross-Sectional Study in Japanese

Objectives

Several serum biomarkers have been reported to increase in periodontitis patients as possible mediators linking periodontal inflammation to systemic diseases. However, the relationship between periodontitis and urine biomarkers is still unclear. The aim of this cross-sectional study was to investigate potential urine biomarkers of periodontitis in a Japanese population.

Materials and Methods

This study included 108 male subjects, and microbiological and clinical parameters were evaluated as a periodontitis marker. The correlation between nine urine biomarkers (typically used to diagnose kidney disease) and periodontal parameters was analyzed. Based on the findings, β₂-microglobulin (β₂-MG) and neutrophil gelatinase-associated lipocalin (NGAL) were selected for comparison and multivariate regression analysis, and the Kruskal–Wallis test followed by Bonferroni correction was used to identify differences in their concentrations between the three periodontitis groups (severe, moderate, and no/mild periodontitis).

Results

β₂-MG and NGAL exhibited a significant correlation with clinical parameters of periodontitis. The prevalence of clinical parameters such as bleeding on probing and number of sites with probing depth (PD) ≥ 6 mm were greater in the β₂-MG high group (≥300 μg/g creatinine) than in the normal group (P=0.017 and 0.019, respectively). Multivariate regression analysis indicated that the number of sites with PD ≥ 6 mm was independently associated with urine β₂-MG. Moreover, the number of sites with the clinical attachment level (CAL) ≥ 6 mm was greater in the NGAL high group (highest quartile) (P=0.041). Multivariate regression analysis showed that the number of sites with CAL ≥ 6 mm was associated independently with urine NGAL. Finally, β₂-MG was significantly higher in the severe periodontitis subjects compared to the no/mild periodontitis subjects.

Conclusion

The significant association between urine β₂-MG or NGAL and periodontitis was revealed. These biomarkers can potentially be used to screen for or diagnose periodontitis. This trial is registered with the UMIN Clinical Trials Registry UMIN000013485.

Indirect regulation of PCSK9 gene in inflammatory response by Porphyromonas gingivalis infection

Pro-protein convertase subtilisin/kexin type 9 (PCSK9), a secreted serine protease, regulates serum low-density lipoprotein (LDL) cholesterol levels by targeting the degradation of LDL receptor (LDLR) in the liver. Although previous reports describe elevated levels of PCSK9 in patients with periodontitis, the mechanisms that trigger this increase in serum PCSK9 levels and induce the related inflammatory response remain unclear. In an unc93b1-deficient mouse of Porphyromonas gingivalis infection, nucleic acid antigen recognition via Toll-like receptors was found to promote PCSK9 production, suggesting an indirect role for tumor necrosis factor-α as an inducer of PCSK9 in contrast to that reported in previous studies. Furthermore, PCSK9 production was independent of the TIR domain-containing adapter-inducing interferon-β-dependent signaling pathway. These results indicate that changes in LDLR expression precede an increase in the serum PCSK9 level in the context of an infectious disease such as periodontitis.

Adiponectin confers neuroprotection against cerebral ischemia-reperfusion injury through activating the cAMP/PKA-CREB-BDNF signaling

Ischemic stroke is a severe cerebrovascular disease. Although great progress has been made, the consequent ischemia-reperfusion (I/R) injury is inevitable and affects the therapeutic effect. Adiponectin (APN) is a fat-derived plasma protein that has beneficial actions on cardiovascular disorders. The present study aims to investigate the effect of APN on I/R injury and the potential underlying mechanisms. In step 1, APN were administered for three times (once every 8 h) 24 h before middle cerebral artery occlusion (MCAO). The results indicated that APN treatment reduced infarct volume, neurological deficits and brain water content after I/R injury. Meanwhile, APN was proved to increase the expression of cAMP, PKA, CREB, and BDNF. In step 2, mice were randomly assigned into the Vehicle + I/R, APN + I/R, PKA activator + I/R, PKA inhibitor + APN + I/R groups. PKA activator, PKA inhibitor, as well as APN were administered for three times before MCAO. The results indicated that PKA inhibitor downregulated the expressions of cAMP, PKA, CREB, and BDNF which subsequently weakened the protective effects of APN on cerebral I/R injury. In conclusion, our findings further suggest that APN exerts protective effect against cerebral I/R injury might through the cAMP/PKA-CREB-BDNF signaling pathway. APN is a novel candidate in the treatment of I/R diseases in the future.