DHEA (dehydroepiandrosterone), the popular hormone widely sold as a nutritional supplement to fight conditions from cancer to aging, does in fact have a beneficial effect on the vascular function of the heart, a new University of California San Francisco study shows.
Though there has been limited scientific basis for claims that DHEA is a potent anti-disease and anti-aging drug, the new study, which will be presented today (Nov. 10) at the American Heart Association Scientific Sessions in Dallas, shows that DHEA does protect the heart against some cardiovascular diseases.
Scientists suspect DHEA -- which is synthesized by our own bodies, is converted into the hormones estrogen and testosterone and decreases sharply with age -- does indeed have a link to conditions including aging, heart disease and cancer, said UCSF cardiology research fellow Christian Zellner, MD, who conducted the study under the direction of UCSF Stanford Health Care cardiologists Tony Chou, MD, UCSF assistant professor of medicine, and Kanu Chatterjee, MD, UCSF professor of medicine, at UCSF's Vascular Lab.
Researchers at medical centers across the country are investigating a number of DHEA-related issues, including DHEA?s role in brain diseases, including Alzheimer's disease, and autoimmune diseases, such as lupus. Some of the lingering questions also include why only humans and primates manufacture the hormone and why it diminishes sharply with age.
This study, part of UCSF's continuing research of DHEA's effects on cardiovascular health, is an important step in giving scientific credence to the role and benefits of DHEA, Zellner said. The research is also a step in understanding any possible untoward effects on individuals who take the drug with high hopes of beating aging and disease, Zellner said. That is important, he said, because an increasing number of people are taking DHEA, yet its sale is unregulated by the FDA.
The animal study, conducted on pigs, shows that DHEA can reverse the effects of Endothelin-1, or ET-1, a peptide that is elevated in most heart diseases, including heart attacks and high blood pressure.
A balance between ET-1 and nitric oxide is essential for maintaining vascular tone, which is necessary for controlling blood pressure, maintaining the tone of coronary arteries and regulating blood flow to the heart and other parts of the body, Zellner said. When ET-1 is elevated the heart's vessels constrict, meaning the flow of blood is hampered and the heart's tissue does not get the oxygen and nutrients it needs to perform well and stay healthy.
The study, however, found that DHEA reversed that vascular constriction and re-established bloodflow.
This year marks the third year in a row that UCSF's Vascular Lab, one of the few groups in the country researching DHEA's effects on heart disease, will present findings on the topic at the AHA conference. The UCSF group showed previously that DHEA dilates the coronary arteries in a similar way to anti-anginal drugs like nitroglycerin and increases the function of the endothelial cells, which create the inner lining of the arteries and offer protection against a wide range of cardiovascular disorders, including atherosclerosis.
Though DHEA has become increasingly popular as a nutritional supplement, there is still a lot of scientific work that needs to be done to make sure the hormone is both safe and beneficial, Zellner said. No human studies examining the cardiac effects of DHEA have been completed, which is essential before any recommendations involving the drug can be made, Zellner said.
The study was funded by the UCSF Foundation for Cardiac Research. Other researchers include: Amanda Browne, BS, Dorina Gheorghevici, MD, Alice Guh, BS, UCSF Vascular Lab; Krishnankutty Sudhir, MD, Baker Medical Institute, Melbourne, Australia; Kanu Chatterjee, MD, Tony Chou, MD, UCSF.