Porphyromonas gingivalis infection and cell death in human aortic endothelial cells

Porphyromonas gingivalis is a periodontal pathogen that promotes a proatherogenic response in endothelial cells. Cell death responses of human aortic endothelial cells to P. gingivalis at various multiplicities of infection (MOI) were investigated by assessment of cell detachment, histone-associated DNA fragmentation, lactate dehydrogenase release and ADP:ATP ratio. Porphyromonas gingivalis at MOI 1 : 10-1 : 100 did not have a cytotoxic effect, but induced apoptotic cell death at MOI 1 : 500 and 1 : 1000. Monocyte chemoattractant protein-1 production was significantly enhanced by P. gingivalis at MOI 1 : 100. At higher MOI, at least in vitro, P. gingivalis mediates endothelial apoptosis, thereby potentially amplifying proatherogenic mechanisms in the perturbed vasculature.