Figure 2. Cellular changes in adipose and skeletal muscle with aging.

In adipose tissue, aged progenitor cells have reduced proliferative capacity and undergo more cellular senescence, and adipocytes’ ability to undergo lipolysis is diminished. Immune cell infiltration increases with age, and accumulation of aging-dependent regulatory cells is seen. In skeletal muscle, mitochondrial function is decreased with aging, satellite cells lose ability to maintain quiescence, and myocytes undergo atrophy.