1. University of Florida, Biochemistry of Aging Laboratory, College of Health and Human Performance, Center for Exercise Science, Gainesville, Florida 32611;
2. Complutense University, Department of Animal Biology-II, Madrid 28040, Spain; and
3. Department of Biochemistry and Molecular Biology, University of Bari, Center of Study on Mitochondria and Energetic Metabolism, National Council of Research, 70125 Bari, Italy