(PHILADELPHIA) Scientists at the Center for Translational Medicine at Thomas Jefferson University in Philadelphia have staved off heart failure in animals by using gene therapy to shut down the adrenal glands excessive output of fight or flight hormones such as epinephrine and norepinephrine. By blocking GRK2, an important regulatory enzyme, they cut the hormone production that forces the heart to pump too hard, leading to heart failure. Such a novel approach targeting the adrenal gland in addition to the heart provides a potential new strategy against heart failure, and could lead to a new class of drugs.
The researchers, led by Walter Koch, Ph.D., W.W. Smith Professor of Medicine and director of the Center for Translational Medicine in the Department of Medicine at Jefferson Medical College, report their findings February 18, 2007, in an advance online publication in the journal Nature Medicine.
The emphasis has always been in treating right at the heart, says Stephen B. Liggett, M.D., director of the cardiopulmonary genomics program at the University of Maryland School of Medicine, who has written an accompanying editorial. Despite our best efforts, about half of all heart failure patients die within five years of diagnosis, so clearly something new is needed. These results add a completely new dimension to the way physicians might be able to intervene to improve heart failure therapy. When an individuals heart begins to fail, the sympathetic nervous system, attempting to compensate for the weakened heart, goes into overdrive, pumping out increasing levels of stimulants catecholamines such as epinephrine and norepinephrine, making a bad situation worse. The typical treatment beta blockers inhibit the beta adrenergic receptors on the heart, blocking the hormones that force the heart to work overtime.
Dr. Kochs group focused instead on the source of catecholamines the adrenal gland. It discovered that in heart failure,
Contact: Steve Benowitz
Thomas Jefferson University