SLC40A1 and hemochromatosis: Beyond anemia and hemochromatosis [113], FPN dysregulation contributes to multisystem pathologies: its deficiency induces memory impairment by promoting ferroptosis in Alzheimer disease [114]; while hepatic FPN downregulation drives proliferation and M2-like polarization of macrophages and leading to hepatic fibrosis through increased the levels of the M2 markers CD206, TGF-β, VEGF, MMP-9, Laminin, Collagen, IL-4 and IL-10 [115], etc. So as the sole iron exporter, FPN is strictly regulated.