Scientists at the University of Pittsburgh School of Medicine have identified a novel mechanism by which the body may combat insulin resistance and diabetes. This discovery involves enhancing a specific type of "good" immune cell within fat tissue. These preclinical findings suggest a potential pathway for developing medications to treat and prevent type 2 diabetes, potentially serving as an alternative or supplement to GLP-1 weight maintenance drugs.
"The discovery could be key to reversing insulin resistance and addressing type 2 diabetes, given the increasing rates of obesity and associated chronic diseases."
— Partha Dutta, Ph.D., D.V.M., senior author and director of the Center for Cardiovascular Inflammation
The Role of Inflammation in Diabetes
Research indicates that inflammation, driven by immune signals from excess fat surrounding abdominal organs, contributes to the insulin resistance leading to type 2 diabetes. Dutta's team investigated this process through studies on mice and human tissue.
Uncovering "Good" Immune Cells
Their findings show that a subset of immune cells, called resident macrophages, located in fat tissue are beneficial. These cells are not inflammatory but rather suppress the inflammation that causes insulin resistance. Resident macrophages are essential for clearing dead cells, fighting infections, and maintaining tissue health.
SerpinB2: A Key to Macrophage Survival
SerpinB2, a protein, aids in the survival of resident macrophages. The research highlights that when excess visceral fat accumulates, leading to overweight or obesity, inflammation increases, and SerpinB2 levels decrease. This reduction causes resident macrophages to die, allowing fat tissue to expand and become more inflamed. This process ultimately impairs the body's insulin response, leading to the development of diabetes.
Preclinical Evidence: Antioxidants Show Promise
In experiments, overweight mice with insulin resistance demonstrated improved insulin sensitivity and increased levels of resident macrophages after receiving antioxidant supplements. This finding supports the concept that protecting these beneficial cells can improve metabolic health.
Future Directions: Towards a New Medication
Dutta's team is currently working to identify a small molecule that improves SerpinB2 levels, with the aim of developing a medication for clinical trials. This medication is intended to protect resident macrophages and halt the fat accumulation and inflammation associated with type 2 diabetes. It is also expected to aid individuals already diagnosed with type 2 diabetes, potentially in conjunction with GLP-1 medications, to address instances where GLP-1 effectiveness plateaus.