Artery, Or Vein – That Is The Question

During embryonic development, endothelial progenitor cells that will become the body’s first artery and vein (the aorta and the cardinal vein) mingle in a single vascular structure. The signals that make some of the cells choose to become artery and some to become vein are not well understood.

Tao Zhong, Ph.D., and colleagues have now clarified the role of the Hedgehog (Hh) signaling pathway in artery-vein cell decisions during early zebrafish development.

They report in the May 1 issue of Developmental Biology that endothelial progenitor cells must receive Hh signals to form the aorta – without Hh signaling, the cells become venous cells instead. Time-lapse imaging in vivo revealed two waves of migrating endothelial progenitor cells – the first wave formed the aorta, the second formed the cardinal vein. In embryos lacking Hh signaling, only the second wave occurred, with expansion of the cardinal vein.

Understanding Hh-dependent mechanisms that regulate artery-vein cell specification could lead to novel therapeutic strategies for coronary heart disease and cancer.

For other research highlights from Vanderbilt University Medical Center laboratories, see ‘Aliquots‘ in the VUMC Reporter.