Molecular analysis of chronological lifespan increase of Saccharomyces cerevisiae by intermittent fasting and intermittent calorie restriction

초록

Caloric restriction (CR) is the most well studied non-genetic factor known to extend the health and lifespan of a wide range of species. Although the benefits of CR have been widely studied and well known, it is difficult to practice CR for a prolonged period of time. Many researchers have devoted considerable efforts to identifying approaches that could be used to mimic the anti-aging effects of CR. Intermittent fasting (IF) and intermittent CR (ICR) are among such CR-based strategies that have been demonstrated to provide beneficial effects similar to those CR. However, little is known regarding the molecular mechanisms whereby IF and ICR promote lifespan extension. To elucidate the beneficial effects of these CR mimetics, we examined the molecular phenotypes and chronological life span (CLS) of yeast cells following IF and ICR treatments. We observed that although both IF and ICR efficiently prolonged yeast CLS, ICR was more effective in promoting CLS extension. Further molecular analyses revealed that both IF and ICR induce CLS extension via mechanisms similar to those revealed for CR. CLS and Cox2p levels were increased by either IF or ICR treatment. CLS extension and Cox2p levels of ICR-treated cells were comparable to the CR-treated cells. The effects of ICR treatment in CLS extension and Cox2p level increase were more pronounced than IF treatment. It is presumed that these results are because, unlike IF, nutritional deficiencies are not experienced during ICR. Our findings in this study revealed that the effects of ICR on yeast CLS are more pronounced than those of IF, and that repetitive ICR can be as effective as continuous CR in promoting yeast CLS extension.