A MEDICATION that is usually used to treat depression and anxiety disorders has the potential to prevent heart failure, say US scientists.

Dr John Tesmer, pharmacology professor at the University of Michigan Medical School, and his research team, found that paroxetine, a selective serotonin reuptake inhibitor (SSRI), inhibits a protein kinase that becomes over-expressed when people have heart failure.

Although so-called "off target" effects are known for many commonly used drugs, this is the first report that identifies a direct link between a specific SSRI and a protein target in the body’s signal system, say the researchers.

Their paper is published online in the journal Chemical Biology.

The discovery almost did not happen, and was "serendipitous", the team says. Before doing a larger search for compounds that would inhibit the protein, known as G protein-coupled receptor kinase 2, the researchers screened a small library of approximately 2,000 compounds, containing many approved drugs, as a test of their screening procedure.

Paroxetine is approved by the US regulatory body, the Food and Drug Administration, and has been clinically used as an SSRI for nearly 30 years; at prescribed doses it appears not to inhibit the identified protein sufficiently to treat heart failure.

If the researchers can identify modifications to the chemical structure of paroxetine, that improve potency while decreasing SSRI activity, they hope to develop the compounds into therapeutic leads, Tesmar says.

Newswise