A common oral pathogen Porphyromonas gingivalis induces myocarditis in rats

Aim To evaluate whether Porphyromonas gingivalis ( P. gingivalis ) inoculation could induce cardiac remodelling in rats. Materials and Methods The study was conducted on 33 Wistar rats, which were distributed in the following experimental groups: not inoculated; inoculated with 1 × 10 8 CFU/ml of bacteria; inoculated with 3 × 10 8 CFU/ml of bacteria. The animals were inoculated at baseline and on the 15th day of follow‐up. Blood collection was performed at baseline and 60 min after each inoculation. At 29 days, the animals were subjected to echocardiography and at 30 days to haemodynamic studies before sacrificing them. Results Impact of the bacteria was more evident in rats that received higher P. gingivalis concentration. Thus, 3 × 10 8 CFU/ml of bacteria increased the rectal temperature and water content in the lung as well as myocardial necrosis and fibrosis. P. gingivalis induced the intensification of DNA fragmentation and increased the levels of malondialdehyde, oxidized proteins, and macrophage expression in the myocardium. These findings were associated with lower LV isovolumetric relaxation time, +d P /d t , –d P /d t , and higher end‐diastolic pressure. Conclusions P. gingivalis bacteraemia is significantly associated with adverse cardiac remodelling and may play a biological role in the genesis of heart failure.