Immune cells of diabetes patients interact with fat from the diet, causing chronic inflammation and leading to diabetes complications.
Diabetes is a chronic condition that often leads to multiple complications, such as decreased kidney function, heart attacks and strokes. Chronic inflammation observed in diabetes patients is one of the leading causes of these complications. What causes chronic inflammation, however, has largely been a mystery until now. A team of researchers led by Dr. Semenkovich at the Washington University School of Medicine discovered that the immune system may play a role.
A diet high in fat promotes chronic inflammation. Using mice as their models, the researchers found that when specific immune cells, called macrophages, are unable to manufacture their own fat, the chance of chronic inflammation and diabetes is reduced, even if mice eat a high-fat diet. Synthesis of fats inside macrophages is mediated by an enzyme fatty acid synthase (FAS). When it is active, FAS promotes specific changes on the membranes of macrophages, which makes them responsive to fat consumed from the diet and activates chronic inflammation. Using genetic tools, the researchers knocked down the activity of FAS in macrophages of mice and discovered that these mice did not develop chronic inflammation, even when they consumed a diet rich in fats.
The number of diabetes patients keeps increasing, and despite major advances made in the last few decades for the control of blood sugar, patients still suffer from numerous diabetes complications. Recent research shows that even those patients, who are able to control their blood glucose with medication very well, still develop complications, such as kidney and vision problems, heart attacks, and strokes. This suggests that high blood sugar is not the whole story. Inflammation that accompanies diabetes seems to be doing a lot of damage, independently of sugar.
The findings published by Dr. Semenovich’s team in the journal Nature have important implications for the treatment of diabetes, and perhaps even other conditions, such as cancer, that involve chronic inflammation. Although this research is still in its infancy and has only been performed on mice, it provides direction for further studies. The scientific community can now look into medications that could affect FAS in macrophages and subsequently curb inflammation as potential treatment for diabetes.
Although this treatment may be promising, completely blocking inflammation is problematic, as inflammatory response is used by the body to fight off infections. New treatment strategies may need to look into ways to block FAS to curb chronic inflammation, without affecting the immune response to pathogens.
Written By: Valeriya Laskova, MSc