Circadian Protein Linked to Vascular Calcification in Diabetes, finds study

A study published in Arteriosclerosis, Thrombosis, and Vascular Biology has identified Bmal1 as a potential key driver of vascular calcification in Diabetes Mellitus. Upregulation of Bmal1 in diabetic arteries was found to activate RUNX2, promoting arterial calcification. These findings suggest a novel mechanistic link between circadian regulation, diabetes, and vascular disease.

Vascular calcification is a major contributor to cardiovascular mortality in diabetes and is driven in part by osteogenic reprogramming of vascular smooth muscle cells. Diabetes is also associated with vascular rhythm disruption, but how circadian regulators contribute to vascular calcification is poorly understood.

A new study from the University of Alabama at Birmingham addressing this mechanism has been selected as one of only two feature articles in the April 2026 issue of Arteriosclerosis, Thrombosis, and Vascular Biology, a journal of the American Heart Association.

The study identified an unexpected role for Bmal1, a core circadian protein, in diabetes-related vascular calcification. Using diabetic mouse models, human arterial tissues and vascular smooth muscle cells, the researchers found the Bmal1 is selectively upregulated in diabetic arteries and directly activates RUNX2, a protein-coding gene and master regulator of osteogenic reprogramming. This drives vascular smooth muscle cells toward a bone-like state, promoting arterial calcification and stiffness.

An accompanying editorial piece highlighted the conceptual importance of the study, noting that the findings reframe Bmal1 from a traditional circadian clock regulator to an active driver of diabetic vascular calcification. The editorial emphasized the potential of this work to open new therapeutic avenues for diabetic vascular disease.

“Our study reveals a novel mechanism linking diabetes, circadian signaling and vascular disease,” said Ming He, M.D., Ph.D., who led the study and is an assistant professor in the Department of Pathology Division of Molecular and Cellular Pathology. “This work identifies Bmal1 as a promising target for future discovery.”