What are the molecular mechanisms driving cellular senescence, telomere shortening, and epigenetic alterations associated with aging-related diseases and degenerative conditions, and how can advances in regenerative medicine, stem cell therapies, and rejuvenation strategies mitigate age-related decline and extend healthspan to enhance quality of life and promote healthy aging?How do social determinants of health, including poverty, education, employment, and access to healthcare, shape health outcomes and health disparities across diverse populations, and what community-based interventions, policy reforms, and advocacy efforts are needed to address structural inequities and foster health equity in underserved communities, particularly among marginalized and vulnerable populations?