P. gingivalis LPS Upregulates IL-6 and IL-8 in HCAECs

Objectives: Porphyromonas gingivalis as a key periodontopathogen has been associated with cardiovascular disease, possibly through metastatic infection and inflammation pathways. The purpose of this study was to evaluate the effect of P. gingivalis lipopolysaccharide (LPS) on the expression of pro- and anti-inflammatory cytokines in human coronary endothelial cells. Methods: Human coronary artery endothelial cells (HCAECs) (Sciencell, USA) were cultured to confluence in 12-well plates with endothelial cell medium (Sciencell). The cells were treated with P. gingivalis LPS (Invivogen, USA) at concentrations of 1ng/mL, 10ng/mL, 100ng/mL, 1ug/mL and 10µg/mL for 12 hr. The levels of IL-1β, IL-1ra, IL-6, IL-8 and IL-10 in the culture media (pg) were measured by enzyme-linked immunosorbent assay (ELISA), and normalized to the total protein quantity (µg). Results: The expression levels of IL-6 and IL-8 in HCAECs were significantly upregulated by P. gingivalis LPS at 10µg/mL (p<0.01). On the other hand, P. gingivalis LPS did not significantly affect the expression of IL-1β and IL-10. IL-1ra was not detectable. Conclusion: This preliminary study suggests that P. gingivalis LPS may upregulate the expression of pro-inflammatory cytokines in HCAEs, and it could potentially increase the risk of coronary artery dysfunction. Further study is required to confirm the current findings and the underlying molecular mechanisms involved.