The role of cellular lipid metabolism in aging

Lipid and energy metabolism plays an important role in regulating longevity and cellular aging process. Many of the biological pathways that regulate longevity involve lipid biology and metabolism. As two essential organelles for energy storage and production, triglyceride-lipid droplets (TG-LDs) and mitochondria have been increasingly appreciated in aging and age-related diseases. Their dysfunction contributes to ectopic TG accumulation, altered fatty acid utilization, and elevated oxidative stress associated with human aging. In the past few decades, numerous efforts have focused on discoveries and characterizations of senescent cells, their roles in tissue aging and dysfunction, and age-related diseases. In the process of senescence, cells undergo significant remolding of lipid and energy metabolism and alterations of bioactive lipids. In this chapter, we focus on the general concepts of TG storage versus mobilization, the role of mitochondria in lipid and energy metabolism, and how lipid and mitochondrial metabolism regulates longevity and aging process at the whole-body as well as cellular levels.