Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast.
The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.
Division of Biotechnology, College of Life Sciences & Biotechnology, Korea University, Seoul 136-701, Republic of Korea.
Joon-Seok
JS
Choi
Cheol-Koo
CK
Lee
D000255:Adenosine Triphosphate / Q000737:chemistry*; D003470:Culture Media; D004247:DNA / Q000378:metabolism*; D004579:Electron Transport; D004734:Energy Metabolism; D005434:Flow Cytometry; D053078:Membrane Potential, Mitochondrial; D008928:Mitochondria / Q000378:metabolism*; D018384:Oxidative Stress; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism; D013997:Time Factors
D003470:Culture Media; D013481:Superoxides; D000255:Adenosine Triphosphate; D004247:DNA
2′,7′-dichlorodihydrofluorescein diacetate; 3,3′-dihexyloxacarbocyanine iodide; 8-OHdG; 8-hydroxydeoxyguanosine; ATP; Aging; Budding yeast; CLS; CR; Caloric restriction; Chronological lifespan; DNPH; DiOC(6); ETC; H2DCFDA; RLS; ROS; caloric restriction; chronological lifespan; dinitrophenylhydrazine; electron transport chain; reactive oxygen species; replicative lifespan