Does calorie restriction induce mitochondrial biogenesis? A reevaluation.
It has been reported that 30% calorie restriction (CR) for 3 mo results in large increases in mitochondrial biogenesis in heart, brain, liver, and adipose tissue, with concomitant increases in respiration and ATP synthesis. We found these results surprising, and performed this study to determine whether 30% CR does induce an increase in mitochondria in heart, brain, liver, adipose tissue, and/or skeletal muscle. To this end, we measured the levels of a range of mitochondrial proteins, and mRNAs. With the exception of long-chain acyl-CoA dehydrogenase protein level, which was increased ∼60% in adipose tissue, none of the mitochondrial proteins or mRNAs that we measured were increased in rats subjected to 30% CR for 14 wk. There was also no increase in citrate synthase activity. Because it is not possible to have an increase in mitochondria without any increase in key mitochondrial proteins, we conclude that 30% CR does not induce an increase in mitochondria in heart, brain, liver, adipose tissue, or skeletal muscle in laboratory rodents.
Washington University School of Medicine, Division of Geriatrics and Nutritional Sciences, 4566 Scott Ave., Campus Box 8113, St. Louis, MO 63110, USA.
Chad R
CR
Hancock
Dong-Ho
DH
Han
Kazuhiko
K
Higashida
Sang Hyun
SH
Kim
John O
JO
Holloszy
D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism; D031204:Caloric Restriction; D005786:Gene Expression Regulation / Q000502:physiology*; D008099:Liver / Q000378:metabolism; D008297:Male; D008928:Mitochondria / Q000145:classification / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D024101:Mitochondrial Proteins; D012333:RNA, Messenger