Abstract
Anemia is often observed in protein-energy malnutrition, and one of the major reasons for this is thought to be iron deficiency. It is now known that hepcidin-25 plays a critical role in iron metabolism. However, no reported studies have yet investigated the relationship between hepcidin-25 and nutritional conditions. From this viewpoint, we investigated the relationship between hepcidin-25-related iron metabolism and protein-energy malnutrition using rats fed a protein-free diet during their growth period. In addition, we investigated how the presence and absence of iron in a protein-free diet affects iron metabolism. Our findings suggested that anemia observed in protein-energy malnutrition during the growth period was attributable to functional iron deficiency, i.e. impairment of iron metabolism due to an increase of hepcidin-25 synthesis, and not to absolute iron deficiency. The iron supply would incur a risk of inducing an excess of iron, since the stored iron was increased in protein-energy malnutrition and no iron deficiency was observed even in the absence of an iron supply. Thus, it appears that the best way to overcome this disease condition is to rectify the nutritional deficiency.
