Macrophage Iron Metabolism Mediates Immunometabolic Reprogramming and Tissue Homeostasis: From Molecular Mechanisms to Clinical Translation

BACKGROUND: Macrophages were long regarded as passive executors of erythrophagocytosis responsible for systemic iron recycling. However, increasing evidence has reframed them as immunometabolic hubs that sense diverse environmental cues to modulate systemic iron homeostasis. MAIN BODY: This review examines the molecular architecture underlying macrophage iron metabolism and outlines how iron metabolic processes are dynamically regulated across spatial and temporal scales through the integration of mechanotransductive, mitochondrial, and epigenetic signaling pathways. Across disease contexts, macrophage iron handling displays marked heterogeneity, exemplified by contact-dependent iron transfer in tumors and ferroptosis-driven instability in cardiovascular disease. In cardiovascular pathologies, iron overload is associated with enhanced ferroptosis-related cascades that contribute to atherosclerotic plaque instability. Furthermore, at mucosal interfaces, host-pathogen competition over nutritional immunity highlights epigenetic strategies by which pathogens perturb host iron machinery. CONCLUSIONS: Linking these mechanistic insights to clinical translation, emerging therapeutic strategies are discussed that move beyond non-specific systemic iron chelation toward more targeted interventions. These include engineering macrophages for targeted drug delivery, exploiting nanomedicine-based redox modulation to influence macrophage phenotypes, and non-invasive regulation via the gut microbiota-epigenetic axis. Collectively, elucidating macrophage iron metabolic networks provides a conceptual framework for the development of precision approaches to inflammatory, metabolic, and malignant diseases.