Cell Senescence and the Aging Liver.

The liver has an enormous functional reserve, including a regenerative capacity that remains remarkable into old age, helping maintain liver function during physiological aging in the absence of specific disease processes. However, significant morphological and functional changes still occur in the aging liver, including the emergence and accumulation of senescent cells. While cell senescence is sometimes equated with aging at the cellular level, its precise role and significance in shaping the aged phenotype in tissues and the whole organism remain debated. Current evidence suggests that each cell type in the liver may contribute specifically to aging and age-associated morbidities. This review focuses on the "heterogeneity of senescence" and highlights the multifaceted role of cell senescence and its associated secretory patterns in aging. However, a better understanding of the complex interplay among cell types is essential for modulating the positive impact of senescence and delaying the emergence of age-associated changes.