A protein targeted by some diabetes drugs might also help to regulate daily cycles in blood pressure and heart rate.
Thiazolidinediones are widely prescribed for the treatment of type 2 diabetes, and work by activating a protein called PPAR-γ. Tianxin Yang of the University of Utah in Salt Lake City and his colleagues investigated the cardiovascular role of this protein using mice that lacked expression of the gene that encodes PPAR-γ in vascular smooth-muscle cells.
Rhythmic variations in blood pressure and heart rate, as well as in the expression of several body-clock genes in blood vessels, were diminished in these mice. Furthermore, normal mice treated with a thiazolidinedione called rosiglitazone showed increased expression of Bmal1, a clock gene.