Molecular Regulation and Clinical Implications of Iron Homeostasis in Human Health and Disease

Iron is an essential micronutrient critical for numerous biological processes, including oxygen transport, mitochondrial respiration, DNA synthesis, and enzymatic reactions. However, its redox activity also renders it potentially toxic, necessitating precise regulation of its absorption, transport, storage, and recycling. This review explores the molecular mechanisms that govern iron homeostasis at both systemic and cellular levels, highlighting the pivotal roles of hepcidin, ferroportin, transferrin, divalent metal transporter 1 (DMT1), and iron regulatory proteins (IRPs). Dysregulation in these pathways can lead to either iron deficiency or iron overload, both of which are associated with significant morbidity. The paper categorizes iron metabolism disorders into primary and secondary iron overload disorders—such as hereditary hemochromatosis, ferroportin disease, aceruloplasminemia, and transfusional siderosis—as well as iron deficiency syndromes including iron deficiency anemia, anemia of inflammation, and iron-refractory iron deficiency anemia. Emphasis is placed on the genetic basis, pathophysiology, diagnostic biomarkers, and current treatment strategies for each condition. Furthermore, the review discusses the clinical implications of misregulated iron metabolism in systemic diseases such as neurodegeneration, cardiomyopathy, endocrine dysfunction, and malignancy. By integrating recent advances in molecular biology with clinical data, this work underscores the necessity of early diagnosis and tailored therapeutic approaches to mitigate complications arising from iron imbalance. Understanding these intricate regulatory networks provides a foundation for improved management and the development of targeted interventions for iron-related disorders.