Background /Aims: Expression of Hamp1, the gene encoding the iron regulatory peptide hepcidin, is inappropriately low in HFE-associated hereditary hemochromatosis and Hfe knockout mice (Hfe−/−). Since chronic alcohol consumption is also associated with disturbances in iron metabolism, we investigated the effects of alcohol consumption on hepcidin mRNA expression in Hfe−/− mice.
Methods: Hfe−/− and C57BL/6 (wild-type) mice were pair-fed either an alcohol liquid diet or control diet for up to 8 weeks. The mRNA levels of hepcidin and ferroportin were measured at the mRNA level by RT-PCR and protein expression of hypoxia inducible factor-1 alpha (HIF-1α) was measured by western blot.
Results: Hamp1 mRNA expression was significantly decreased and duodenal ferroportin expression was increased in alcohol-fed wild-type mice at 8 weeks. Time course experiments showed that the decrease in hepcidin mRNA was not immediate, but was significant by 4 weeks. Consistent with the genetic defect, Hamp1 mRNA was decreased and duodenal ferroportin mRNA expression was increased in Hfe−/− mice fed on the control diet compared with wild-type animals and alcohol further exacerbated these effects. HIF-1α protein levels were elevated in alcohol-fed wild-type animals compared with controls.
Conclusion: Alcohol may decrease Hamp1 gene expression independently of the HFE pathway possibly via alcohol-induced hypoxia.