The Yale Undergraduate Research Journal


While prior studies have identified recurring genetic patterns, gaps of knowledge still remain in existing aging mechanisms; where they originate, and how they offer insight to environmental disruptions that dictate health over time. Given the inescapability of age-related deterioration and pathology, stitching together current literature may help demystify the biological process common to all living mammals. The physiological disruption of aged tissue reflects a cellular dependence on environmental cues and historical wear. Retaining the capacity to differentiate into any cell type, a stem cell best parallels a call-and-response relationship between organ and cell. As the longest living proliferative cell in multicellular organisms, stem cells respond to environmental cues through genomic or proteomic shifts. Aging tends to disrupt this capability, as stem cells lose functionality over time. This review will focus on the genetic mechanisms associated with stem cell depletion and skin tissue degeneration. By concentrating on genetic pathways common in studies comparing caloric restriction models in young and old species, this review will highlight commonalities that generate age-related stem cell depletion and tissue degeneration.