Abstract
Caloric restriction (CR) has been applied as a powerful tool in aging research. CR is accepted as a robust, reproducible and simple experimental manipulation known to extend both median and maximum lifespans, and to retard and suppress a broad spectrum of pathophysiological changes in a variety of mammals. In general, CR delays skeletal and sexual maturation, reduces body size with less adiposity, lowers body temperature, modulates hyperglycemia and insulinemia, alters lipid and energy metabolisms, protects against internal oxidative and environmental stresses, and activates mitochondrial biogenesis and sirtuins. Based on the adaptive response hypothesis against food shortage, I propose that CR promotes adipose tissue remodeling and modulates energy metabolism via sterol regulatory element binding protein (SREBP) 1c, a master transcriptional factor of fatty acid biosynthesis. Activation of de novo fatty acid biosynthesis regulated by SREBP1c might play an important role in the anti-aging and lifespan extension by caloric restriction.
