Immunosenescence and immune–organ axis dysfunction: Potential of algal bioactives and nutritional interventions for healthy ageing

Aging-associated immunosenescence disrupts various immune pathways-signaling, cellular, metabolic, epigenetic, and inflammatory mechanisms-leading to impaired bidirectional interactions between the immune system and organs. This dysfunction exacerbates geriatric conditions, including neurodegenerative disorders, chronic inflammation, and metabolic syndromes. This review introduces the concept of the immune-organ axis, an underexplored framework connecting immune dysregulation to organ-specific dysfunction. Nutritional interventions, including bioactive compounds, essential nutrients, functional foods, and phytochemicals, are highlighted for their ability to modulate these pathways by inducing autophagy, resolving inflammation, and promoting cellular repair. Furthermore, stabilization and delivery systems are proposed as technological solutions to enhance the efficacy of these interventions. This review emphasizes the need for integrative approaches to mitigate immune dysfunction and improve health outcomes in aging populations, while outlining future research directions to advance this field.