Histological Indicators of Aging at the Cellular Level: Cellular Senescence, Fibrosis, and Regenerative Capacity

Abstract Aging is a complex and multifaceted process characterized by a gradual deterioration of cells and tissue functions. Histological markers such as cellular senescence, fibrosis, and reduced regenerative capacity are key features of aging. Senescent cells accumulation in different tissues is a feature of this senescence, which is linked to chronic inflammation and organ dysfunction. Fibrosis, marked by increasing deposition of extracellular matrix, occurs in aging organs like the liver, heart, and lungs, impairing their function. Aging also declines the regeneration of the tissue, primarily as a result of the depletion of tissue-resident stem cells. This study highlights the histological changes associated with aging, offering insights into how aging influences cellular mechanisms and predisposes individuals to age-related diseases that are related to age, like cardiovascular lesions, neurodegeneration, and metabolic disorders. Understanding these indicators could guide the development of therapeutic approaches to reduce age-related tissue degeneration.