NAD+ Biosynthesis Enzyme Protects Aortic Smooth Muscle Cells: Preclinical Findings

Synopsis

The walls of the aorta weaken with age and stress, risking serious damage. Smooth muscle cells (SMCs) in the aorta need NAD+, made by the enzyme NAMPT, for health. In humans with aortic disease, lower NAMPT in SMCs correlated with larger aortic size. Mice lacking NAMPT in SMCs had less NAD+, mild aortic dilation, and were prone to aortic injury from stress. These cells showed DNA damage and signs of early aging, which improved when NAD+ was restored using nicotinamide riboside. In diseased human aortas, low NAMPT was linked to DNA damage and gene silencing by DNA methylation. This suggests that maintaining NAD+ production in SMCs protects against DNA damage and premature aging of the aorta.

Journal

Circulation Research