IIT-Kanpur researchers discover how immune cells stop insulin release

Researchers at the Indian Institute of Technology-Kanpur have found a new way that immune cells in the pancreas can quickly stop insulin release. This discovery points to a possible new target for making drugs to protect insulin production in people with obesity and Type-2 diabetes. The study shows that immune cells called macrophages can turn off insulin made by nearby beta cells within minutes. This happens much faster than the slow damage caused by inflammation over months or years. Simran Singh and Ashish Kumar led the study as co-first authors under the guidance of Sai Prasad Pydi, an assistant professor in the department of biological sciences and bioengineering at IIT-Kanpur. Pydi stated that they found immune cells next to beta cells can switch off insulin release very quickly. The process uses fats called sphingolipids, which are released by macrophages instead of the inflammatory proteins usually linked to obesity-related pancreas damage. The team tracked the trigger to a receptor on macrophages named GPR18. When this receptor is activated, the immune cells release sphingolipids. Nearby beta cells take up these fats through a surface transporter, which interferes with how they make insulin. Using a precise genetic method, the researchers found that turning on this pathway lowered insulin secretion in mouse models. Turning it off improved insulin release. Blocking GPR18 or other steps in the pathway also brought back insulin secretion.

Results And Context

The team worked with the Indiana Biosciences Research Institute in the US to confirm that this same pathway exists and works in human pancreatic tissue. Activating it in donated human tissue also blocked insulin secretion. While this study does not provide an immediate cure or treatment for diabetes, the findings give researchers a clear target for developing future drugs to help people with obesity and Type-2 diabetes keep their insulin production safe.

Context

Type-2 diabetes and obesity are major health concerns linked to how the body handles sugar and insulin. Beta cells in the pancreas are responsible for producing insulin, a hormone that controls blood sugar levels. Understanding the exact cellular pathways involved in insulin suppression helps researchers design targeted treatments for metabolic conditions.