Northern analysis of hepcidin mRNA expression in mouse models of anemia.

Northern analysis of hepcidin (A) and β-actin (B) expression in mouse liver tissue. Quantitative measurements of nonheme liver iron are recorded for each mouse at the bottom of panel A. We determined β-actin expression to normalize for RNA loading. Hepcidin mRNA expression in livers of C57BL/6J mice (lane 1) was less than that of 129/SvEvTac mice (lane 2). This result is consistent with the observation that wild-type 129/SvEvTac mice generally have higher iron stores than wild-type C57BL/6J mice. Anemic sla/Y mice (lane 3) have low liver iron stores and low hepcidin levels when compared with wild-type mice of the same background strain (C57BL/6J; lane 1). Nonanemic mk/+ mice (lane 4) have more liver iron and express more hepcidin than anemic mk/mk homozygotes (lane 5), which have low iron stores and microcytic anemia. Homozygoushpx/hpx mice cannot efficiently deliver iron to developing red blood cells, resulting in severe anemia despite tissue iron overload (1594 μg iron per gram of liver). These mice have decreased hepcidin mRNA expression (lane 7) when compared with nonanemic littermates (lane 6). These results are representative of 2 experiments without significant variation between experiments.