Carvedilol shown to have unique characteristics among beta blockers

Nov 20, 2009

In a new study, researchers report that a class of heart medications called beta-blockers can have a helpful, or harmful, effect on the heart, depending on their molecular activity.

The study, which appears in the journal Circulation Research, found that that target both the alpha- and beta-receptors on the muscle offer the most benefit to cardiac patients, while those that target only the beta-receptors can actually undermine the structure and function of the heart.

Circulation Research is published by the American Heart Association.

Heart disease is the leading cause of death in the United States. Patients with heart disease usually have higher levels of catecholamines - hormones that activate the beta-adrenergic receptors to stimulate cardiac muscle contraction. In this process, the heart initially grows to become a more efficient pump. Unfortunately, the researchers found, this growth also predisposes the heart to eventual failure.

Traditionally, beta-blockers targeting the beta-adrenergic receptors have been utilized as a long-term therapy for heart failure.

Interestingly, blocking adrenergic receptors has been widely used clinically for nearly 50 years without a full understanding of the molecular consequences of these drugs, said co-author and graduate student David Cervantes. Kevin Xiang, a professor of molecular and integrative physiology at the University of Illinois led the study. The research team also included researcher Catherine Crosby.

A previous study in 2003 showed that the beta-blocker carvedilol produced a greater survival benefit than another drug, metoprolol tartrate. Carvedilol targets both the beta- and alpha-adrenergic receptors.

The new study unveiled an elegant intracellular signaling system in which beta-receptor activation modulates alpha-adrenergic signaling. It showed that blocking the beta-receptor alone promotes cardiac remodeling via growth of cardiac fibroblasts induced by alpha-adrenergic receptor signaling. The growth of fibroblasts in the heart further damages the integrity and function of the heart.

This observation suggests that the use of carvedilol in combination with inhibitors of angiotensin-converting enzyme (ACE inhibitors) may be of the greatest benefit to cardiac patients, and has significant clinical implications on which beta-blockers patients should take.

"I think this is really good stuff," Xiang says. "It's a surprise project. It's not what we initially intended looking into. But it's a very nice, elegant study and a very beautiful cellular mechanism. It definitely will help people along the way to understand how to further manipulate this system. Beta blockers are still the most commonly used drug for heart disease."

Source: University of Illinois at Urbana-Champaign (news : web)

Explore further: Flu vaccine may hold key to preventing heart disease

add to favorites email to friend print save as pdf

Related Stories

Two beta blockers found to also protect heart tissue

Sep 15, 2008

(PhysOrg.com) -- A newly discovered chemical pathway that helps protect heart tissue can be stimulated by two of 20 common beta-blockers, drugs that are prescribed to millions of patients who have experienced heart failure.

Heart failure treated 'in the brain'

Mar 25, 2008

Beta-blockers heal the heart via the brain when administered during heart failure, according to a new study by UCL (University College London). Up to now, it was thought that beta-blockers work directly on the heart, but ...

Beta-blockers given the boot in Britain

Jun 28, 2006

British doctors are being advised not to prescribe beta-blockers and to ease most current users off them and onto new treatment for high blood pressure.

Recommended for you

Supercomputers link proteins to drug side effects

Oct 20, 2014

New medications created by pharmaceutical companies have helped millions of Americans alleviate pain and suffering from their medical conditions. However, the drug creation process often misses many side ...

No added benefit proven for umeclidinium/vilanterol in COPD

Oct 20, 2014

The drug combination umeclidinium/vilanterol (trade name Anoro) has been approved since May 2014 for adults with chronic obstructive pulmonary disease (COPD). In an early benefit assessment pursuant to the Act on the Reform ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

HeartSisters
not rated yet Nov 24, 2009
I was unable to find any conflict of interest disclosures on this study. Who funded Dr. Xiang's carvedilol study? Could it possibly have been GlaxoSmithKline(manufacturer of Coreg)? or Roche (Dilatrend and Eucardic)? or maybe its generic drugmaker Cipla?

Carolyn Thomas
http://www.ethicalnag.org