Interpretive Summary: H-ferritin in sows’ colostrum- and milk-derived extracellular vesicles: a novel iron delivery concept

By: Kondaiah Palsa, James R Connor, John Flanagan, Elizabeth A Hines

Colostrum and milk are the primary sources of nutrition for lactating mammals. Iron is an essential nutrient for nursing mammals. Piglets are routinely iron deficient and do not obtain adequate iron from sows’ milk further contributing to anemia observed in young pigs. Additional information about the proteins that carry iron from the sow’s breast milk to understand the bioavailability of iron and potential routes for reducing the incidence of anemia in offspring are clearly needed. We have discovered that H-ferritin (FTH1) is a potent iron transport protein and is not limited to iron storage as previously thought. Therefore, our objective was to determine whether the FTH1 is present in the sow’s colostrum and milk. Furthermore, there are extracellular vesicles released from cells that are known to transport FTH1 and are reportedly present in sows’ milk. Our study showed that FTH1 was present in the colostrum and milk and enriched in the milk-derived EVs. This study reveals a new protein and mechanism for iron delivery during lactation in sows that may be targeted to decrease iron deficiency in piglets.