Key immune-related hub genes BTK, ITGAL and PTX3 mediate macrophage phenotypic shift and foam cell formation in the periodontitis-atherosclerosis axis.

BACKGROUND

Periodontitis has been increasingly associated with atherosclerosis, contributing to increased risk of cardiovascular disease, especially coronary artery disease. This study is aimed to identify the molecular cross-talks between periodontitis and atherosclerosis using bioinformatics approaches and validate their roles using siRNA-mediated in vitro experiments.

METHODS

Transcriptomic datasets related to periodontitis and atherosclerosis were extracted from the Gene expression omnibus based on specific criteria. Weighted gene co-expression network analysis was performed using the iDEP 2.0 to identify gene co-expression modules associated with disease phenotypes. Functional enrichment analysis was used to select hub genes linking the two diseases, which were then validated experimentally. Selected hub genes were evaluated for foam cell formation by Oil red O staining (qualitative and quantitative), and gene expression using qPCR in RAW264.7 murine macrophages treated with lipopolysaccharide- P.gingivalis and ox-LDL transfected with siRNAs targeting selected genes.

RESULTS

The analysis using iDEP 2.0 revealed 2,574 co-expressed genes within the turquoise module, significantly enriched in immune system activation, cell adhesion, chemokine signaling and cytokine receptor interactions. Network analysis identified BTK, ITGAL and PTX3 as key hub genes. siRNA-mediated knockdown of these genes revealed a significant reduction in foam cell formation. qPCR analysis showed downregulation of iNOS and overexpression of Arg1 and IL10, indicating a shift of macrophages from M1 to M2 phenotype.

CONCLUSION

This study identified BTK, ITGAL and PTX3 as key hub genes playing central roles in immune cell recruitment, activation, and foam cell formation, thereby suggesting their role as molecular mediators linking chronic periodontal inflammation to atherogenesis.