Work by University at Buffalo researchers has identified a link between obesity and gum disease. As gum disease escalates, it degrades the bone tissue around teeth, elevating the risk of tooth loss.
Obese individuals are more at risk of having gum disease; they also experience heightened levels of systemic inflammation.
In the study, featured in the Journal of Dental Research, the scientists pinpointed the immune culprits responsible for the surge in chronic inflammatory flare-ups: cells called myeloid-derived suppressor cells, or MDSC. These cells originate from bone marrow stem cells, and their numbers explode in pathological situations such as cancer and infections.
MDSCs were of particular interest in the context of periodontal (gum) disease as they can change into a bone-guzzling cell called an osteoclast. Previously, researchers had mapped a triad of factors that culminate in tooth loss—gum disease spikes inflammation, which ramps up osteoclast activity.
Now, the team led by Keith Kirkwood from the University at Buffalo School of Dental Medicine fills in the blanks of how obesity fits into the picture.
“This research promotes the concept that MDSC expansion during obesity to become osteoclasts during periodontitis is tied to increased alveolar bone destruction,” commented Kyuhwan Kwack, one of the scientists on Kirkwood’s team.
In a series of animal studies, Kirkwood and colleagues took a closer look at how different diets influenced the risk of alveolar bone loss. This is the bone tissue that sits at the interface of teeth and jawbones.
One group of mice was given a low-fat diet, while the other received a high-fat diet, f which nearly half of their calories came from fat. Unsurprisingly, the animals in the high-fat diet group experienced higher rates of obesity and inflammation due to their diet. On a cellular level, the researchers observed that obese animals had an uptick in osteoclast activity around the alveolar bone.
A panel of 27 genes linked to osteoclast development was also significantly upregulated in the high-fat diet group.
These findings serve as a jumping-off point for future investigations into how other bone diseases such as osteoporosis tend to develop parallel to obesity-related chronic inflammation.