Porphyromonas gingivalis lipopolysaccharide inhibits trophoblast invasion in the presence of nicotine

•LPS purified from Porphyromonas gingivalis hardly suppressed trophoblastic invasion in vitro.•The suppression was significantly enhanced by nicotine treatment.•The synergic effect was p38 MAPK dependent.

IntroductionPeriodontitis is a chronic infectious disease associated with Gram-negative subgingival microflora. In pregnant women, periodontitis is thought to be associated with adverse pregnancy outcomes, although the pathophysiology is unknown. Additionally, smoking is an established risk factor for adverse pregnancy outcomes. In the present study, we examined the direct effects of Porphyromonas gingivalis lipopolysaccharides (PGLPS) and nicotine on a trophoblast cell line.MethodsHTR-8/SVneo cells were plated on Matrigel chambers with or without PGLPS and nicotine. The invasive activity of the cells was directly evaluated using microscopy.ResultsPGLPS alone did not reduce the invasive activity of the HTR-8/SVneo cells. The co-administration of nicotine with PGLPS significantly reduced the invasive activity of the cells.DiscussionOur results suggest that although the direct pathogenic effects of P. gingivalis alone on trophoblast invasion may be limited, concurrent smoking reduces trophoblast invasion into the myometrium and inhibits maternal vascular reconstruction.