Absorption of lactoferrin-iron in suckling pigs

Abstract

Lactoferrin is the major iron-binding protein in human milk, and is believed to be of importance in the mechanism of iron absorption. The absorption and retention of iron from iron-saturated bovine lactoferrin was studied in suckling pigs using 59Fe, and compared to absorption and retention of FeSO 4. Lactoferrin bound iron was absorbed and incorporated into red blood cells to the same extent that sulphate iron. Net iron retention, measured by whole body counting of radioactivity one week after administration of a tracer dose, also showed a similar uptake of lactoferrin bound iron and sulphate iron. The results demonstrate that the iron-deficient suckling pig utilizes iron from lactoferrin at least as well as from an inorganic salt. Uptake data give rise to the hypothesis that the mechanisms for transfer of iron from mucosa to serosa and the incorporation of iron into red blood cells, may differ for the two compounds.