What is the mechanism by which hepcidin regulates iron metabolism in the body?

A By increasing the expression of transferrin receptors on cell surfaces
B By decreasing the absorption of iron from the gut and increasing iron sequestration in macrophages ✓
C By stimulating the production of erythropoietin, leading to increased red blood cell production
D By inhibiting the synthesis of heme, a key component of hemoglobin

Explanation

Hepcidin plays a central role in iron metabolism by regulating iron absorption from the gut and iron recycling from macrophages. It acts by binding to ferroportin, leading to its internalization and degradation, which results in decreased iron export from cells and thus decreased plasma iron levels.

Source

Molecular Biology of the Cell by Alberts et al.
Hematology Hematology: Anemia Hematology: Anemia Hard MEDICAL Confidence: high