Using a murine periodontitis model, a previous study found that infection with Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia for 16 weeks led to significant plasma NO level reduction, NO-related pathway (tetrahydrobiopterin/neuronal nitric oxide synthase/Nuclear factor (erythroid-derived 2)-like 2 (BH4/nNOS/NRF2)) inhibition in the colon and plasma, and atherosclerotic plaque area increase. This evidence concerns the gene NFE2L2 and periodontitis.