Core B: Project Summary: The objective of Core B (Mouse Aging Analysis Core ) is to provide a centralized core facility for the PPG at the Yale School of Medicine that will generate and analyze transgenic mouse models to determine the roles of local adipose FGF21 on lifespan extension and age-related functional decline across multiple systems. The Core B will allow the PPG to gain mechanistic insights into the pro-longevity effects of local FGF21 and role of augmentor-α-ALK signaling, across multiple organ systems (adipose tissue, liver, bone, CNS and the immune system) using measures of functional decline in aging, longevity and burden of disease as primary endpoints. The Aim 1 of Core B is be work closely with the leader of the Administrative Core and leaders of the research projects, to assist in the experimental design and execution of the animal research phase of the individual projects, and to assure efficiency and standardization of procedures. Aim 2: To complete the omnibus study with male and female mice examining the effect of adipose specific inducible overexpression of FGF21 on lifespan. Aim 3: To determine the impact of FGF-21 superagonist (FGF21SA) on lifespan, inflammaging and healthspan. Aim 4: To perform healthspan analyses of mice with overexpression of FGF21 mouse in augmentor-α knockout models.