Bleeding gums can lead to lung disease, a study suggests.
Researchers in China found that mice were infected with the oral bacteria Porphyromonas gingivalis, which can lead to gum disease.
This worsened the progression of chronic obstructive pulmonary disease (COPD) in mice that already had the condition.
The findings suggested that Treating gum disease could act as a potential treatment for COPD, which affects 16 million American adults and is the sixth leading cause of death worldwide.
About 40 percent of American adults over 30 have gum disease — and the problem has been linked to serious, chronic health problems like lung cancer
Dr. Yan Li, co-lead study author and microbiologist at the West China Hospital of Stomatology at Sichuan University, said: ‘Our findings could lead to a potential new strategy for treating COPD.’
Periodontal disease results from the untreated build-up of plaque, a sticky film composed primarily of bacteria.
Over time, plaque can harden into tartar and cause irritation and inflammation of the gums. This causes deep gaps between the teeth and gums where bacteria thrive, resulting in bleeding or swollen gums, bad breath and tooth loss.
Previous studies have shown that gum disease is a risk factor for many diseases, including diabetes, high blood pressure and some cancers.
This is because gum disease increases inflammation, which signals to the body that something is wrong. This triggers an immune response, and if that response is too strong, it can increase the risk of chronic disease.
Additional studies, including some led by Dr. Li and co-lead author Dr. Boyu Tang, have shown that the bacterium Porphyromonas gingivalis plays an important role in gum disease by destroying tissues that support the teeth.
For the new work, the researchers infected mice with both the bacteria and COPD. The animals became infected with COPD through exposure to cigarette smoke.
By testing lung tissue from mice, they found that Porphyromonas gingivalis activated the production of immune cells called gamma-delta T cells and M2 macrophages.
This created cytokines, which in excess can increase inflammation in the body, leading to worsening conditions such as COPD.
Dr. Tang said: ‘By improving periodontal therapy and targeting the inhibition of gamma-delta T cells and M2 macrophages, we may be able to help control the progression of COPD.’
COPD is a chronic inflammatory lung disease that causes obstructed airflow.
According to the Mayo Clinic, this leads to difficulty breathing, as well as wheezing, chest tightness, chronic cough, frequent respiratory infections, lack of energy, unintentional weight loss and swelling in the ankles, feet or legs.
Smoking is the most important risk factor for COPD. When it progresses, it can increase the risk of heart problems, high blood pressure and lung cancer.
According to the World Health Organization, COPD is the sixth leading cause of death in the world. It affects 16 million Americans.
Meanwhile, about 40 percent of Americans over the age of 30 have gum disease.
The researchers plan to conduct further experiments on humans.
Dr. Li said: ‘If exposure to cigarette smoke could be extended for a longer period, these changes could be more obvious.
‘We will further conduct additional studies on human subjects to confirm the mechanism.’
The team plans to recruit patients with both conditions and offer periodontal disease treatment, then compare lung function and immune cell counts before and after.
The research was published in the journal on Friday mSystems.