Newly discovered hormone may be a critical driver of type 1 and type 2 diabetes

A newly identified hormone named fabkin that helps regulate metabolism may play a significant role in the development of both type 1 and type 2 diabetes, according to research led by the Sabri Ülker Center for Metabolic Research at Harvard T.H. Chan School of Public Health.

The study showed blood levels of fabkin were abnormally high in mice and human patients with either type 1 or type 2 diabetes. The researchers found that blocking the activity of fabkin prevented the development of both forms of diabetes in the animals. The research suggests fabkin likely plays a similar role in humans.

Researchers found that fabkin targets the insulin-producing beta cells of the pancreas and is a driving force behind the development of diabetes. When an antibody was used to neutralize fabkin in mice, the animals did not develop diabetes. When the antibody was given to obese, diabetic mice, they reverted to a healthy condition.

Many hormones are involved in the regulation of metabolism, such as insulin and leptin, the researchers said. Fabkin is different in that it is not a single molecule with a single defined receptor. Instead, fabkin is composed of a functional protein complex consisting of multiple proteins, including fatty acid binding protein 4 (FABP4), adenosine kinase (ADK), and nucleoside diphosphate kinase (NDPK).

The researchers determined that fabkin regulates energy signals outside of cells. These signals then act through a family of receptors to control target cell function. In the case of diabetes, fabkin controls the function of beta cells in the pancreas that are responsible for insulin production, the researchers said.

“For many decades, we have been searching for the signal that communicates the status of energy reserves in adipocytes to generate appropriate endocrine responses, such as the insulin production from pancreatic beta cells,” said senior author Gökhan S. Hotamisligil, director of the Sabri Ülker Center, in a statement. “We now have identified fabkin as a novel hormone that controls this critical function through a very unusual molecular mechanism.”