Ma, S. et al. Cell 180, 984–1001 (2020)

Aging elicits different responses across cell types, tissues and organs, which hampers our understanding of this process. Caloric restriction (CR) consistently increases lifespan across multiple species, but the mechanisms through which CR exerts this effect are also not well understood. In a new study published in Cell, investigators compared the transcriptomic profile of 210,000 single cells and nuclei across nine types of tissues from young and old rats (Rattus Norvegicus) subjected to ad libitum feeding, and old rats subjected to CR. The transcriptomic atlas uncovered age-associated features at the molecular, cellular, tissue, and organismal levels, which were rescued by CR. These findings enhance our understanding of aging, confirm the powerful effects CR, and could inform new geroprotective interventions.