A new molecular signaling pathway in fat cells that suppresses harmful inflammation has been identified by Harvard School of Public Health researchers. The pathway prevents the fat cells — called adipocytes — from over-reacting to inflammation-causing stimulants such as fatty acids in the diet.

However, the researchers also found that obesity-related cellular stress can override the protective function and turn the pathway into a trigger of chronic inflammation, leading to increased risk of insulin resistance, diabetes and other metabolic disorders.

In lean people, the newly identified signaling pathway acts as a natural counterbalance to a parallel signaling pathway that promotes inflammation and can lead to health problems.

“Overt obesity eventually overwhelms the protective effect of this pathway and flips it into the pro-inflammatory pathway,” senior author Chih-Hao Lee, assistant professor of genetics and complex diseases, said in a prepared statement.

Lee and colleagues also pinpointed the molecular switch that determines which pathway is activated under different conditions. They said it may be possible to develop drugs designed to increase the protective effect to more strongly suppress inflammation and reduce the risk of insulin resistance, diabetes and other health problems.

The study was published in the journal Cell Metabolism.