Activation of Intestinal HIF2α Ameliorates Iron-Refractory Anemia

Adv Sci (Weinh). 2024 Mar;11(12):e2307022. doi: 10.1002/advs.202307022. Epub 2024 Jan 20.

Abstract

In clinics, hepcidin levels are elevated in various anemia-related conditions, particularly in iron-refractory anemia and in high inflammatory states that suppress iron absorption, which remains an urgent unmet medical need. To identify effective treatment options for various types of iron-refractory anemia, the potential effect of hypoxia and pharmacologically-mimetic drug FG-4592 (Roxadustat) are evaluated, a hypoxia-inducible factor (HIF)-prolyl hydroxylase (PHD) inhibitor, on mouse models of iron-refractory iron-deficiency anemia (IRIDA), anemia of inflammation and 5-fluorouracil-induced chemotherapy-related anemia. The potent protective effects of both hypoxia and FG-4592 on IRIDA as well as other 2 tested mouse cohorts are found. Mechanistically, it is demonstrated that hypoxia or FG-4592 could stabilize duodenal Hif2α, leading to the activation of Fpn transcription regardless of hepcidin levels, which in turn results in increased intestinal iron absorption and the amelioration of hepcidin-activated anemias. Moreover, duodenal Hif2α overexpression fully rescues phenotypes of Tmprss6 knockout mice, and Hif2α knockout in the gut significantly delays the recovery from 5-fluorouracil-induced anemia, which can not be rescued by FG-4592 treatment. Taken together, the findings of this study provide compelling evidence that targeting intestinal hypoxia-related pathways can serve as a potential therapeutic strategy for treating a broad spectrum of anemia, especially iron refractory anemia.

Keywords: FG‐4592; HIF; anemia of inflammation; chemotherapy‐induced anemia; hypoxia; iron‐refractory iron deficiency anemia.

MeSH terms

  • Anemia* / drug therapy
  • Anemia, Refractory* / drug therapy
  • Animals
  • Fluorouracil / therapeutic use
  • Glycine
  • Hepcidins / therapeutic use
  • Hypoxia
  • Iron
  • Isoquinolines / pharmacology
  • Isoquinolines / therapeutic use
  • Mice

Substances

  • Fluorouracil
  • Glycine
  • Hepcidins
  • Iron
  • Isoquinolines
  • endothelial PAS domain-containing protein 1