Comparative Evaluation of Serum Tumor Necrosis Factor α in Health and Chronic Periodontitis: A Case-Control Study

Humic Acid Derived from Agricultural Biomass Mitigates Alveolar Bone Loss and Modulates Systemic Inflammatory Cytokines in Rats with Periodontitis

BACKGROUND

Humic acid (HA) is a bioproduct that can be extracted from different sources and has anti-inflammatory properties that have been little explored in the treatment and prevention of Periodontal Disease (PD). Thus, we aimed to investigate the effects of oral administration of HA on the progression of PD in rats.

METHODS

Twenty-four male Wistar rats were distributed into three experimental groups (Control/ Sham, PD, and PD + HA). HA was administered by gavage (80 mg/kg/day) for 28 days, and PD was induced 14 days after the beginning of treatment. Bone loss, bone topography, and surface elemental composition were analyzed. Circulating IL1-beta, TNF-alpha, and IL-10 levels were evaluated through Enzyme-Linked Immunosorbent Assay (ELISA).

RESULTS

The animals treated with HA showed lower bone loss (p < 0.05). Calcium and phosphorus levels on the alveolar bone surface were lower in the PD group (p < 0.05) compared to the control group, whereas the animals treated with HA exhibited attenuation in this loss (p < 0.05). The animals treated with HA showed reduced TNF-alpha, IL1-beta, IL-10, and the TNF-alpha/IL-10 ratio compared to those with PD (p < 0.05).

CONCLUSION

Treatment with HA attenuated the parameters of alveolar bone loss and modulated systemic inflammatory parameters in rats with ligature-induced PD.

Anti-Osteoclastogenesis Potential of Cocoa Pod Husk (Theobroma cacao L.) Extract: In Silico and In Vivo Study

Periodontitis is a common chronic inflammatory disease characterized by alveolar bone loss. The high polyphenol content in cocoa pod husk (Theobroma cacao L) has the potential to influence bone metabolism and contribute to the inhibition of bone resorption. The aim of this study was to analyze the anti-osteoclastogenesis potential of cocoa pod husk (Theobroma cacao L.) in both in silico and in vivo study. An analysis of the anti-osteoclastogenesis potential of T. cacao bioactive compounds was conducted using molecular docking simulations. Thirty male Wistar rats (Rattus novergicus) were randomly assigned to control negative groups (placebo gel), control positive groups (2% doxycycline gel), and treatment groups (10% cocoa pod husk (CPH) extract gel), with measurements taken on days 7 and 14. Wistar rats were induced with 0.05 ml of P. gingivalis at a concentration of 2x109 CFU/ml intrasulcularly in the maxillary molar to achieved in periodontitis. The number of osteoclasts was observed by hematoxylin and eosin staining, the level of TNF-α was assessed by enzyme-linked immunosorbent assay, and the expression of RANKL was evaluated by immunohistochemical staining. Data were analyzed using One-way ANOVA to examine the differences between the groups. The in silico study showed that the catechin, epicatechin, quercetin, and procyanidin B2 had a strong binding affinity for TNF-α and RANKL. Administration of 10% CPH reduced the number of osteoclasts (p<0.05), TNF-α level on days 7 and 14 (p<0.05), and RANKL expression on day 7 (p<0.05) in experimental rats with periodontitis. Administering 10% CPH inhibited osteoclastogenesis in the experimental periodontitis rats.

Effect of chronic periodontitis on the endothelial glycocalyx of rat penile corpus cavernosum

BACKGROUND

Chronic periodontitis may induce erectile dysfunction (ED), however, the specific mechanism involved is unclear. The endothelial glycocalyx (eGlx) is a structure that can regulate endothelial nitric oxide synthase (eNOS) phosphorylation on the cavity surface of vessels.

AIM

To investigate whether chronic periodontitis leads to ED by affecting the eGlx.

METHODS

Twenty-four 4-week-old male Sprague‒Dawley rats were randomly divided into four groups (n = 6): the control group, chronic periodontitis group, chronic periodontitis + heparin group (subcutaneous heparin 200 U/kg/day, 7 days), and control + heparin group. Four weeks after the induction of periodontitis in the rats, the maximum intra-cavernous pressure/mean arterial pressure (ICPmax/MAP), serum C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), nitric oxide (NO), heparin sulfate (HS), syndecan-1 (SDC-1), heparanase (HPSE), eNOS, and phosphor-eNOS (p-eNOS) concentration were measured, and the eGlx of the penile corpus cavernosum was observed by transmission electron microscopy (TEM).

OUTCOMES

Chronic periodontitis can degrade eGlx on the rat penile corpus cavernosum by increasing serum CRP, TNF-α, and IL-6 levels, reducing the p-eNOS/eNOS ratio and the NO concentration in the penile corpus cavernosum, and resulting in the inhibition of the erectile function.

RESULTS

Serum CRP, TNF-α, and IL-6 levels and HPSE expression in penile cavernous tissue were significantly greater in the chronic periodontitis group than in the control group and the chronic periodontitis + heparin group (P < 0.05). The average thickness of the eGlx muscle in the penile corpus cavernosum in the chronic periodontitis group was significantly lower than those in the control group and chronic periodontitis + heparin group (P < 0.05). The HS concentration, SDC-1 expression, p-eNOS/eNOS, NO concentration, and ICPmax/MAP in the chronic periodontitis group were significantly lower than those in the control group and chronic periodontitis+ heparin group (P < 0.01).

CLINICAL IMPLICATIONS

The eGlx on penile cavernosum vessels may be a new therapeutic target for the treatment of ED.

STRENGTHS AND LIMITATIONS

This study revealed that chronic periodontitis promotes the decomposition of vascular eGlx in the rat penile corpus cavernosum, however, it is not clear whether chronic periodontitis inhibits the synthesis of eGlx.

CONCLUSION

Chronic periodontitis can degrade eGlx on the rat penile corpus cavernosum by increasing serum CRP, TNF-α, and IL-6 levels, reducing the p-eNOS/eNOS ratio and the NO concentration in penile cavernous tissue, and resulting in the inhibition of the erectile function. Heparin inhibited eGlx decomposition and improved erectile function in rats with chronic periodontitis.

Automated Machine Learning to Develop Predictive Models of Metabolic Syndrome in Patients with Periodontal Disease

Metabolic syndrome is experiencing a concerning and escalating rise in prevalence today. The link between metabolic syndrome and periodontal disease is a highly relevant area of research. Some studies have suggested a bidirectional relationship between metabolic syndrome and periodontal disease, where one condition may exacerbate the other. Furthermore, the existence of periodontal disease among these individuals significantly impacts overall health management. This research focuses on the relationship between periodontal disease and metabolic syndrome, while also incorporating data on general health status and overall well-being. We aimed to develop advanced machine learning models that efficiently identify key predictors of metabolic syndrome, a significant emphasis being placed on thoroughly explaining the predictions generated by the models. We studied a group of 296 patients, hospitalized in SCJU Sibiu, aged between 45-79 years, of which 57% had metabolic syndrome. The patients underwent dental consultations and subsequently responded to a dedicated questionnaire, along with a standard EuroQol 5-Dimensions 5-Levels (EQ-5D-5L) questionnaire. The following data were recorded: DMFT (Decayed, Missing due to caries, and Filled Teeth), CPI (Community Periodontal Index), periodontal pockets depth, loss of epithelial insertion, bleeding after probing, frequency of tooth brushing, regular dental control, cardiovascular risk, carotid atherosclerosis, and EQ-5D-5L score. We used Automated Machine Learning (AutoML) frameworks to build predictive models in order to determine which of these risk factors exhibits the most robust association with metabolic syndrome. To gain confidence in the results provided by the machine learning models provided by the AutoML pipelines, we used SHapley Additive exPlanations (SHAP) values for the interpretability of these models, from a global and local perspective. The obtained results confirm that the severity of periodontal disease, high cardiovascular risk, and low EQ-5D-5L score have the greatest impact in the occurrence of metabolic syndrome.

The Phenolic Profile and Anti-Inflammatory Effect of Ethanolic Extract of Polish Propolis on Activated Human Gingival Fibroblasts-1 Cell Line

Propolis, owing to its antibacterial and anti-inflammatory properties, acts as a cariostatic agent, capable of preventing the accumulation of dental plaque and inhibiting inflammation. The anti-inflammatory properties of propolis are attributed to caffeic acid phenethyl ester (CAPE), which is present in European propolis. The objective of the conducted study was to assess the anti-inflammatory effects of the Polish ethanolic extract of propolis (EEP) and isolated CAPE on stimulated with LPS and IFN-α, as well as the combination of LPS and IFN-α. The cytotoxicity of the tested compounds was determined using the MTT assay. The concentrations of specific cytokines released by the HGF-1 cell line following treatment with EEP (25-50 µg/mL) or CAPE (25-50 µg/mL) were assessed in the culture supernatant. In the tested concentrations, both CAPE and EEP did not exert cytotoxic effects. Our results demonstrate that CAPE reduces TNF-α and IL-6 in contrast to EEP. Propolis seems effective in stimulating HGF-1 to release IL-6 and IL-8. A statistically significant difference was observed for IL-8 in HGF-1 stimulated by LPS+IFN-α and treated EEP at a concentration of 50 µg/mL (p = 0.021201). Moreover, we observed that CAPE demonstrates a stronger interaction with IL-8 compared to EEP, especially when CAPE was administered at a concentration of 50 µg/mL after LPS + IFN-α stimulation (p = 0.0005). Analysis of the phenolic profile performed by high-performance liquid chromatography allowed identification and quantification in the EEP sample of six phenolic acids, five flavonoids, and one aromatic ester-CAPE. Propolis and its compound-CAPE-exhibit immunomodulatory properties that influence the inflammatory process. Further studies may contribute to explaining the immunomodulatory action of EEP and CAPE and bring comprehensive conclusions.

Systemic Inflammation, Endothelial Function, and Risk of Periodontitis in Overweight/Obese Adults

The network interaction between systemic inflammatory mediators, endothelial cell adhesion function, and adiponectin as mediators of the association between metabolic diseases and periodontitis has not been evaluated. The objective of this study is to assess whether the interaction of baseline serum levels of TNF-α, hs-CRP, ICAM-1, VCAM-1, and adiponectin leads to periodontitis. Five hundred and ninety-seven overweight/obese (overweight: BMI 25 to <30 kg/m2; obese: >30 kg/m2) adults, aged 40-65 years, with complete 3-year follow-up data were included. Generalized structural equation models with negative binomial regression were used to estimate the regression coefficient (β) for the outcome number of teeth with probing pocket depth (PPD) ≥ 4 mm and bleeding on probing (BOP) at 3-year follow-up for a 1 standard deviation unit increase (Δ = +1SD) in each biomarker. After adjusting for multiple covariates, baseline ICAM-1 and VCAM-1 had significant direct effects on increased log-transformed number of teeth with PPD ≥ 4 mm and BOP (β: 0.16; 95% CI: 0.02-0.30; β: 0.15; 95% CI: 0.02-0.30, respectively). Baseline hs-CRP showed a significant indirect effect via ICAM-1 on the log-transformed number of teeth with PPD ≥ 4 mm and BOP (β: 4.84; 95% CI: 0.27-9.42). Thus, elevated serum ICAM-1 and VCAM-1 have a significant direct effect and increased hs-CRP has a significant indirect effect on the predicted level of periodontitis at the 3-year follow-up among overweight/obese Hispanic adults.

Association between Caspase-1, TNF-α Salivary Level and Their Diagnostic Potential to Discriminate Periodontitis from Healthy Control

PURPOSE

Periodontitis is associated with caspase and proinflammatory mediators, such as caspase-1 and tumor necrosis factor-alpha (TNF-α). The aim of this study was to evaluate the salivary levels of caspase-1 and TNF-α and determine their accuracy in differentiating periodontitis patients from individuals with a healthy periodontium.

MATERIALS AND METHODS

This case-control study enrolled 90 subjects, aged 30 to 55, attending the Department of Periodontics at Baghdad's outpatient clinic. Patients were initially screened to evaluate their eligibility for recruitment. After applying inclusion/exclusion criteria, subjects with a healthy periodontium were included in group 1 (controls), while subjects with periodontitis were included in group 2 (patients). The salivary levels of caspase-1 and TNF-α in participants' unstimulated saliva were measured using an enzyme-linked immunosorbent assay (ELISA). Then the periodontal status was determined using the following indices: full-mouth plaque, full-mouth bleeding on probing, probing pocket depth, clinical attachment level, and gingival recession.

RESULTS

TNF-α and caspase-1 salivary levels were higher in periodontitis patients than in healthy controls and were positively correlated with all clinical parameters. A positive significant correlation between TNF-α and caspase-1 salivary levels was noticed. For differentiating periodontal health and periodontitis, the area under the curve (AUC) values of TNF-α and caspase-1 were 0.978 and 0.998, while the proposed cut-off points were 128.163 pg/ml and 1.626 ng/ml, respectively.

CONCLUSION

The present findings supported a previous discovery that periodontitis patients have significantly higher levels of salivary TNF-α. In addition, there was a positive correlation between the salivary levels of TNF-α and caspase-1. Furthermore, caspase-1 and TNF-α showed high sensitivity and specificity in the diagnosis of periodontitis, as well as distinguishing periodontitis from periodontal health.

The Effects of Enriched Rehabilitation on Cognitive Function and Serum Glutamate Levels Post-stroke

Aim

This study aimed to explore the effect of enriched rehabilitation (ER) on cognitive function and serum glutamate levels in patients with stroke.

Methods

Forty patients diagnosed with post-stroke cognitive impairment (PSCI), according to the inclusion criteria, and undergoing inpatient rehabilitation were enrolled in the study. Patients were randomly assigned to receive 8 weeks of ER treatment (ER group; n = 20) or conventional medical treatment (CM group; n = 20). In addition, 20 age-matched healthy subjects who were outpatients in our hospital during the same period formed the healthy control (HC) group. In- and between-group differences in cognitive function were assessed during pre-intervention and post-intervention based on the Montreal Cognitive Assessment (MoCA), the Symbol Digit Modalities Test (SDMT), and the Trail Making Test (TMT). The serum levels of glutamate, tumor necrosis factor (TNF), and malondialdehyde (MDA) levels were also detected pre-intervention and post-intervention.

Results

Pre-intervention cognitive function and the levels of all the serum parameters assessed significant difference between the HC group and the PSCI group (both ER and CM groups) (p < 0.05), but not between the two groups of patients with PSCI (p > 0.05). Significant improvements were observed in cognitive function in both the ER and the CM groups post-intervention compared with pre-intervention, as evidenced by the measured improvement in MoCA, SDMT, and TMT scores. Similar improvements were seen for serum glutamate, the degree of oxidative damage, and the level of inflammation in both the treatment groups (p < 0.05). More enhancements in cognitive function, including MoCA, SDMT, TMT scores, and the serum levels of glutamate, the degree of oxidative damage, and the level of inflammation were shown in the ER group compared with the CM group post-intervention (p < 0.05).

Conclusions

ER can improve cognitive function in patients with PSCI. The associated mechanism may be related to the negative regulatory effect of ER on serum glutamate, TNF, and MDA levels, which is likely to enhance synaptic plasticity and alleviate oxidative stress- and inflammation-related damage, at least to some extent.

Association of the Unstimulated Whole Salivary Cytokine IL-1β Levels with Initial, Moderate and Severe Periodontitis. A Case Control Study

Periodontitis (P) is a highly prevalent inflammatory disease of the oral cavity. The objective of the study was to evaluate the stages of pro-inflammatory cytokine IL-1β in initial, moderate and severe periodontitis. One hundred and twenty two patients were included in the study. Periodontitis subjects had at least 20 natural teeth and ≥8 sites with pocket depths of >4 mm and clinical attachment loss (CAL). A questionnaire was used with respect to the socio demographic parameters which included age, gender, ethnicity, education, marital, residence and occupation. To categorize the severity of the disease, teeth were assessed for, Plaque index (PI), Bleeding on probing (BOP), CAL, missing tooth, tooth mobility and bone loss. Unstimulated whole saliva (UWS) was collected and Interleukin-1β (IL-1β) cytokine levels were analyzed using enzyme linked immunosorbent assay with microplate reader at 450 nm. Clinical parameters and salivary cytokine concentrations were assessed using one-way analysis of variance, whereas a correlation of cases with gender and severity of periodontitis was evaluated using chi-square test. Fifty-nine patients were healthy controls and 63 were periodontitis patients Thirty two percent (n = 20) had initial periodontitis, 40% (n = 25) suffered from moderate and 29% (n = 18) had severe periodontitis. Periodontitis subgroups were significantly different with regards to age and gender (p < 0.001). The mean PPD and CAL among the periodontitis patients (PPD, 3.52 ± 1.25 mm; CAL, 4.04 ± 1.64 mm) were significantly compromised (p < 0.05) compared to healthy controls (PPD, 1.52 ± 0.73 mm; CAL, 0.08 ± 0.28 mm). Increased levels of IL-1β were associated with high CAL and PPD findings. UWS IL-1β levels were higher in periodontitis patients compared to healthy individuals. In addition, cases of severe periodontitis showed significantly higher UWS IL-1β levels compared to initial and moderate periodontitis patients. Comparative levels of salivary IL-1β can be potentially used as a diagnostic tool for periodontitis identification and disease progression along with clinical parameters.

The Potential Impact of Salivary IL-1 on the Diagnosis of Periodontal Disease: A Pilot Study

The aim of this study was to identify inflammatory cytokines as salivary biomarkers for periodontal disease. The subjects were 33 Korean adults aged 23 to 71 years. Using a multiplexed bead immunoassay called Luminex, the levels of inflammatory cytokines related to periodontal disease were evaluated. Oral examination for periodontal disease and gingival bleeding was conducted. With these two independent variables, differences in inflammatory cytokines were analyzed by an independent t-test and age-adjusted ANCOVA. Among the subjects, 21 had periodontal disease and 12 were healthy subjects. The gingival bleeding status was classified into low and high levels. Among 13 inflammatory cytokines in saliva, IL-1α, IL-1β, IL-4, IL-8, CCL2/MCP-1, CCL3/MIP-1α, and TNF-α were found to be significant biomarkers within the standard curve. The quantity of IL-1β was increased in subjects with high levels of gingival bleeding. IL-1α levels were increased in subjects with periodontal disease. After adjusting for age, the significant biomarkers for gingival bleeding and periodontal disease were IL-1β and IL-1α, respectively. Using the receiver operating characteristic (ROC) curve, IL-1β was confirmed as a significant biomarker. The sensitivity and specificity of IL-1β for predicting periodontitis were 88.24% and 62.5%, respectively. Therefore, IL-1 was found to be a significant biomarker for periodontal disease, and it could be used in the diagnosis of periodontal disease using saliva.