Identifying metabolic parameters related to severity and extent of periodontitis in down syndrome patients

Cytokine levels in the gingival crevicular fluid and their association with periodontal status of down syndrome patients: a cross-sectional study

OBJECTIVE

To evaluate cytokine levels of interleukin (IL)-1β, IL-4, IL-6, IL-17a, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ in the gingival crevicular fluid (GCF) of periodontal sites in individuals with Down syndrome (DS) and analyze their relationship with clinical periodontal parameters.

MATERIALS AND METHODS

A cross-sectional study was conducted with 49 DS patients and 32 individuals without DS (non-DS group). Periodontal probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP), and visible plaque index (VPI) were evaluated. The periodontal sites were classified as shallow, moderate, and deep. GCF was collected in all shallow sites and, when present, in moderate and deep sites for the analysis of cytokine levels. The cytokines, IL-1β, IL-4, IL-6, IL-17a, TNF-α, and IFN-γ, were quantified using the Luminex® automatic analyzer system.

RESULTS

The DS group presented greater severity of periodontitis compared to the non-DS group (P = 0.005). The DS group showed a significant direct correlation of IL-1β and an inverse correlation of IFN-γ and IL-14 with all periodontal variables. In the analysis stratified by periodontal pocket depth, we observed a higher level of IFN-γ, IL-17a, IL-1β, and IL-6 in the shallow sites, and IL-17a, IL-1β, and IL-6 in deep pockets of DS group individuals. Multivariate models showed that higher levels of IL-1β, IL-4, IL-6, and IL-17a were associated with Down syndrome even after adjusting for periodontal status, sex, and age.

CONCLUSION

The findings suggest that people with DS have greater periodontal impairment and higher levels of cytokines in GCF, even in sites having clinical periodontal parameters similar to those of individuals without DS. These data reiterate the concept of an altered and less effective immune response in the population with DS in the face of a periodontal microbial challenge.

CLINICAL RELEVANCE

Elevated periodontal inflammation burden can be observed with higher cytokine levels in the gingival crevicular fluid of people with Down syndrome, especially IL-1, IL-4, IL-6, and IL-17, regardless of the stage of periodontitis.

Association of Down syndrome with periodontal diseases: Systematic review and meta-analysis

BACKGROUND

Down syndrome (DS) is distinguished by cognitive disability, a concave profile, and systemic complications. Oral diseases have been reported to be common in DS patients.

OBJECTIVE

To investigate the association between DS and periodontal diseases.

METHODS

Two independent reviewers searched six bibliographic databases up to January 2023 and used additional search methods to identify published studies on gingivitis or periodontitis in people with and without DS. Meta-analysis, risk of bias, sensibility analysis, publication bias, and evidence grading were all carried out.

RESULTS

Twenty-six studies were included for analysis. There was a tendency for increased plaque accumulation, periodontal probing, periodontal attachment level, bleeding on probing and indices in DS individuals. Meta-analysis of 11 studies showed a significant association between DS and periodontitis (OR 3.93; 95% CI 1.81-8.53). Probing depth was significantly high in individuals with DS as compared to controls (mean difference 0.40 mm; 95% CI 0.09-0.70). Gingivitis was significantly associated (OR 1.93; 95% CI 1.09-3.41) with DS in four studies. The evidence was classified as 'moderate certainty'.

CONCLUSION

Medium/low-quality studies demonstrate that Down syndrome is strongly associated with periodontitis and moderately associated with gingivitis.

TIPE2 regulates periodontal inflammation by inhibiting NF-κB p65 phosphorylation

BACKGROUND

The roles and molecular mechanisms of tumor necrosis factor-α-induced protein 8-like 2 (TIPE2) in periodontitis remain largely unknown.

OBJECTIVE

This study aimed to determine the expression of TIPE2 and NF-κB p65 in rat Porphyromonas gingivalis-induced periodontics in vivo.

METHODOLOGY

Periodontal inflammation and alveolar bone resorption were analyzed using western blotting, micro-computed tomography, TRAP staining, immunohistochemistry, and immunofluorescence. THP-1 monocytes were stimulated using 1 μg/ml Pg. lipopolysaccharide (Pg.LPS) to determine the expression of TIPE2 in vitro. TIPE2 mRNA was suppressed by siRNA transfection, and the transfection efficiency was proven using western blotting and real-time PCR. The NF-κB pathway was activated by treating the cells with 1 μg/ml Pg.LPS to explore related mechanisms.

RESULTS

The expression of both TIPE2 and NF-κB p65 was increased in the gingival tissues of rat periodontitis compared with normal tissues. Positive expression of TIPE2 was distributed in inflammatory infiltrating cells and osteoclasts in the marginal lacunae of the alveolar bone. However, strong positive expression of TIPE2 in THP-1 was downregulated after Pg.LPS stimulation. TIPE2 levels negatively correlated with TNF-α and IL-1β. Decreased TIPE2 in THP-1 further promoted NF-κB p65 phosphorylation. Mechanistically, TIPE2 knockdown upregulated NF-κB signaling pathway activity.

CONCLUSIONS

Taken together, these findings demonstrate that TIPE2 knockdown aggravates periodontal inflammatory infiltration via NF-κB pathway. Interventions aimed at increasing TIPE2 may help in the therapeutic applications for periodontitis.