Effect of Caseinophosphopeptides from alpha(s)- and beta-Casein on Iron Bioavailability in HuH7 Cells

摘要

Two pools of caseinophosphopeptides (CPPs) obtained from alpha(s)- and beta-casein fractions (alpha-CPPs and beta-CPPs) were characterized. A total of 16 CPPs were identified in the a-CPPs pool, 9 of them derived from alpha(s1)-casein and 7 from alpha(s2)-casein. A total of 18 CPPs were identified in the beta-CPPs pool. Four of the identified CPPs contained the characteristic phosphoseryl-glutamic acid cluster SpSpSpEE. Calcein assay was used to compare the iron-binding capacity of the alpha- and beta-CPPs pools. At the concentration of 12.5 mu M CPPs used in the iron bioavailability assays, beta-CPPs pools show greater iron-binding capacity than alpha-CPPs pools. HuH7 human hepatoma cells show many differentiated functions of liver cells in vivo and can be used to evaluate iron bioavailability (ferritin content and soluble transferrin receptor) from Fe-alpha-CPPs and Fe beta-CPPs complexes. The alpha-CPPs and beta-CPPs pools did not improve ferritin content or soluble transferrin receptor in HuH7 cells.