The newly discovered bacterium that causes gum disease delivers a one-two punch by also triggering normally protective proteins in the mouth to actually destroy more bone, a University of Michigan study found. Scientists and oral health care providers have known for decades that bacteria are responsible for periodontitis, or gum disease. Until now, however, they hadn’t identified the bacterium.
“Identifying the mechanism that is responsible for periodontitis is a major discovery,” said Yizu Jiao, a postdoctoral fellow at the U-M Health System, and lead author of the study appearing in the recent issue of the journal Cell Host and Microbe. …
The study yielded yet another significant finding: the bacterium that causes gum disease, called NI1060, also triggers a normally protective protein in the oral cavity, called Nod1, to turn traitorous and actually trigger bone-destroying cells. Under normal circumstances, Nod1 fights harmful bacterium in the body.
“Nod1 is a part of our protective mechanisms against bacterial infection. It helps us to fight infection by recruiting neutrophils, blood cells that act as bacterial killers,” Inohara said. “It also removes harmful bacteria during infection. However, in the case of periodontitis, accumulation of NI1060 stimulates Nod1 to trigger neutrophils and osteoclasts, which are cells that destroy bone in the oral cavity.”Giannobile, who also chairs the Department of Periodontics and Oral Medicine at the U-M School of Dentistry, said understanding what causes gum disease at the molecular level could help develop personalized therapy for dental patients. …
- Nod1 is critical for immune responses resulting in commensal-induced oral bone resorption
- A Nod1-stimulating commensal, NI1060, accumulates at damaged gingival sites
- NI1060 is related to a human aggressive periodontitis-associated bacterium
- Nod1 stimulation by NI1060 is important to induce bone resorption
Periodontitis is a common disease that is characterized by resorption of the alveolar bone and mediated by commensal bacteria that trigger host immune responses and bone destruction through unidentified mechanisms.
… Nod1, an innate intracellular host receptor for bacterial peptidoglycan-related molecules, is critical for commensal-induced periodontitis in a mouse model. Mice lacking Nod1 exhibit reduced bone resorption as well as impaired recruitment of neutrophils to gingival tissues and osteoclasts to the alveolar bone, which mediate tissue and bone destruction. Further analysis showed that accumulation of a Nod1-stimulating commensal bacterium, NI1060, at gingival sites was sufficient to induce neutrophil recruitment and bone resorption.
… findings provide insight into commensal-host interactions contributing to periodontitis and identify a potential target for preventing this common oral disease.
This is a reminder to take care of your teeth. Use a remineralizing toothpaste or solution and consider probiotics to outcompete any bad bacteria you may have.