GAINESVILLE --- It's mid-morning on Cape Cod and the thermometer has barely climbed above 50 degrees, but 72-year-old Joseph Sullivan is out walking. Every day he puts his headphones on and walks two or three miles around Cape Cod's Kelley Park.
"I love to go out and get some fresh air," Sullivan said "It also helps me to stay in relatively decent shape."
But Sullivan is doing more than just staying physically fit. He is generating in his heart a protein called Heat Shock Protein 72, or HSP72, which protects against injury in the event of a heart attack.
According to a recent study by University of Florida researchers, less than a week's worth of walking, jogging or cycling can help the heart produce enough HSP72 to protect it against the damage done during a heart attack.
"We've done studies that indicate that as little as three days of exercise can provide protection," said Scott Powers, a professor in UF's department of exercise and sport sciences. In rats tested at UF, as few as five days of exercise produced almost the maximum amount of HSP72 that cells can hold.
"It raises the possibility that this could be true of humans, too, and we think that this is very exciting," Powers said.
HSP72 is in a family of proteins that form in the cells and protect organs in the body, such as the heart, against the type of extreme stress that a heart attack can cause. During stress, scientists believe, HSP72 can stabilize and refold damaged proteins, which is vital to preserving the heart if blood circulation is cut off.
"The whole problem of a heart attack is that if cells die, they're gone forever," Powers said. "What this heat shock protein does is to prevent the cell from dying from stress that would kill cells that didn't have the same level of stress protein. You're wounded, but you don't die."
Funded by the American Heart Association-Florida Affiliate, the series
Contact: Scott Powers
University of Florida