Protein found to aid heart function in old age

A protein called vinculin helps in sustaining the performance of cardiac muscle cells as we grow old, new research says.

Human heart makes precious few new cells but manages to generate billions of life-sustaining beats as it grows old.

"The heart is an amazingly resilient organ but one that generally doesn't regenerate and its ability to pump invariably declines with age," said Anthony Cammarato, co-principal investigator and an assistant professor of medicine and physiology at Johns Hopkins University School of Medicine.

"Our findings reveal that vinculin fuels beneficial structural and physiologic changes in aging heart cells, and it can be an important therapeutic target to slow down the heart muscle's inevitable demise," Cammarato said.

The new findings about the role of vinculin could pave the way to treatments that extend the lives of patients afflicted by heart failure.

The protein's presence in organisms of various physiologic complexity is a sure sign of its conservation among species and its evolutionary importance.

In an initial set of experiments, researchers analyzed levels of vinculin in the heart muscle of adult and aging fruit flies, rats and monkeys.

In all three, vinculin levels rose steadily with age. Next, researchers analyzed biopsies from rat hearts.

Compared with cardiac cells obtained from younger rats, tissue from old animals showed notable clustering of vinculin in the cell junctions.

That pattern allows vinculin to boost transmission of mechanical force from cell to cell and enhance overall heart contraction.

"Encircling the cell like a rubber band, vinculin appears to keep its interior impeccably arranged and in doing so ensures that form and performance remain intact," Cammarato said.

"Vinculin appears to be at the heart of a natural defence mechanism that reinforces the aging heart cell and helps it better sense and respond to age-related changes," said senior author Adam Engler, associate professor of bioengineering at University of California, San Diego.

The study appeared in the journal Science Translational Medicine.