UF scientists studied 22 young and old rats, comparing those allowed to eat freely with those fed a low-calorie, nutritious diet.
The stress of a low-calorie diet was enough to boost cellular cleaning in the hearts of older rats by 120 percent over levels seen in rats that were allowed to eat what they wanted. The diet had little or no effect on younger rats.
Autophagy is a housekeeping mechanism that keeps cells free of damaged and thereby detrimental mitochondria and other toxic materials while recycling their building blocks nutrients needed by the cell, said Stephanie Wohlgemuth, Ph.D., a lecturer in UFs department of aging and geriatrics and the studys lead author. So if that process is maintained with age or even increased that can only be beneficial.
To determine how dietary restriction boosted cells ability to reduce the toxic trash, the scientists studied how the amount of certain proteins changed with the rats age and diet. They found that some proteins responsible for degrading the damaged parts of the cell by autophagy were more abundant in older, calorie-restricted mice.
Boosting autophagy is especially important in the heart, a vital organ packed with mitochondria, Wohlgemuth said. Swift disposal of damaged cellular components is essential to maintaining an abundance of healthy heart cells as we age.
Cardiac cells have lost the capability to divide readily to replace dying cells. So the maintenance of the cells survival mechanisms is crucial for the heart, said Wohlgemuth.
Now that some of these proteins have been identified, UF researchers say the next s
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University of Florida