Expression of human caspase-4 in the gingival epithelium affected with periodontitis: Its involvement in Porphyromonas gingivalis-challenged gingival epithelial cells

Overexpression of inflammatory human caspase-4 in relation to clinical severity of oral lichen planus

OBJECTIVE

Involvement of non-canonical inflammasome, comprising inflammatory human caspase-4, caspase-5, and Gasdermin D, in the pathogenesis of oral lichen planus (OLP) has never been demonstrated. We aimed to determine human caspase-4, caspase-5, and Gasdermin D expressions in OLP, to correlate their expressions with OLP severity, and to measure salivary interleukin (IL)-1β levels.

STUDY DESIGN

OLP and normal oral mucosal specimens (n = 42 each) were processed for immunohistochemistry or immunoblotting. The clinical score for OLP severity was assessed at the most severe site. The immunohistochemical (IHC) score was a summation of intensity and positive cell scores. Salivary IL-1β levels were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Median IHC scores of caspase-4 and Gasdermin D in OLP group were significantly greater than those in normal mucosal group (P < .01), consistent with significantly upregulated expressions by immunoblotting (P < .05). The IHC scores of caspase-4 and Gasdermin D were positively correlated with the clinical scores (P < .05). Salivary IL-1β levels in the OLP group were significantly greater than those in the normal mucosal group (P < .001).

CONCLUSIONS

Our study demonstrates enhanced human caspase-4 and Gasdermin D expressions in relation to increased OLP severity with elevated salivary IL-1β levels, proposing clinical applications of these biomolecules as potential prognostic markers and/or new therapeutic intervention for OLP.

Estimation of noncanonical pyroptosis biomarkers gasdermin D and caspase 4 in gingiva of periodontitis and diabetes patients: An observational cross-sectional study

Background

Periodontitis and diabetes are chronic diseases where inflammation plays a central role, with each condition exacerbating the other. Pyroptosis, an inflammatory form of programmed cell death, is implicated in periodontitis and diabetes. The activation of gasdermin D (GSDMD), a key mediator of pyroptosis, promotes cytokine release and perpetuates tissue destruction in both. However, the role of the noncanonical pyroptosis pathway mediated by caspase 4 (CASP4) remains less understood. The study aimed to determine the gene expression of noncanonical pyroptosis biomarkers CASP4 and GSDMD in periodontitis and diabetes individuals and correlate with the periodontal and diabetic parameters.

Materials and Methods

Sixty individuals were recruited and divided into four groups: Group 1 (healthy), Group 2 (periodontitis), Group 3 (diabetes), and Group 4 (periodontitis with diabetes). Gingival tissue samples were collected from all groups, and the relative mRNA expression levels of CASP4 and GSDMD were determined using reverse transcription polymerase chain reaction. The correlation between CASP4 and GSDMD expression and periodontal parameters - plaque index (PI), gingival index (GI), probing pocket depth (PPD), and clinical attachment loss (CAL), as well as diabetic parameters - fasting blood sugar and glycated hemoglobin (HbA1C) was analyzed.

Results

The relative mRNA expression of CASP4 and GSDMD was highest in Group 4 and lowest in Group 1. Statistical significance was observed between the groups (P ≤ 0.05) for CASP4 and GSDMD. A significant positive correlation was found between CASP4 and GSDMD expression and periodontal parameters (PI, GI, PPD, and CAL), as well as the diabetic parameter HbA1C (P ≤ 0.01).

Conclusions

High expression of CASP4 and GSDMD was present in the gingiva of periodontitis and diabetes individuals and correlated with the diabetic and periodontal clinical parameters. This suggests that noncanonical pyroptosis contributes to periodontitis and diabetes pathogenesis through the CASP4/GSDMD axis. The inhibition of GSDMD offers a promising therapeutic approach in managing periodontitis and diabetes.

Host mRNA Analysis of Periodontal Disease Patients Positive for Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Tannerella forsythia

Periodontal disease is a frequent pathology worldwide, with a constantly increasing prevalence. For the optimal management of periodontal disease, there is a need to take advantage of actual technology to understand the bacterial etiology correlated with the pathogenic mechanisms, risk factors and treatment protocols. We analyzed the scientific literature published in the last 5 years regarding the recent applications of mRNA analysis in periodontal disease for the main known bacterial species considered to be the etiological agents: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Tannerella forsythia. We identified new pathogenic mechanisms, therapeutic target genes and possible pathways to prevent periodontal disease. The mRNA analysis, as well as the important technological progress in recent years, supports its implementation in the routine management of periodontal disease patients.