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United States Department of Agriculture

Agricultural Research Service

Research Project: KNOWLEDGE OF SOIL-PLANT-HUMAN FOOD SYSTEMS TO ENHANCE IRON AND ZINC BIOAVAILABILITY IN PLANT FOODS Title: Milk peptides increase iron solubility in water but do not affect DMT-1 expression in Caco-2 cells

Authors
item Argyri, Konstantina -
item Tako, Elad -
item Miller, Dennis -
item Glahn, Raymond
item Komaitis, Michael -
item Kapsokefalou, Maria -

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 12, 2008
Publication Date: February 28, 2009
Citation: Argyri, K., Tako, E., Miller, D., Glahn, R.P., Komaitis, M., Kapsokefalou, M. 2009. Milk peptides increase iron solubility in water but do not affect DMT-1 expression in Caco-2 cells. Journal of Agricultural and Food Chemistry. 57(4):1538-1543.

Interpretive Summary: A model for digestion has been developed in our lab that uses a simulated digestion and Caco-2 epithelial tissue cell culture monolayer to imitate the intestinal lining and absorption of minerals into our bodies. In previous studies we showed that peptide fractions isolated from milk during the simulated digestion increased iron absorption by the Caco-2 cells. These peptides may be considered when formulating foods for children. This study was to investigate how adding peptides fractions isolated from the digested milk to food or drinks would increase iron uptake. Milk peptide fractions enhanced iron dialyzability from water by more than two fold, but not from milk or a vegetable or fruit meal. Lyophilized peptide fractions enhanced iron dialyzability from milk. Our results indicate that milk peptide fractions do not affect expression of DMT-1. Milk peptide fractions preserved their enhancing properties after in vitro digestion but did not increase iron dialyzability from milk or infant meals. Concentrated milk peptide fractions increased iron dialyzability from milk.

Technical Abstract: In vitro digestion of milk produces peptide fractions that enhance iron uptake by Caco-2 cells. Our objectives were to investigate whether these fractions a) exert their effect by increasing relative gene expression of DMT-1 in Caco-2 cells b) enhance iron dialyzability when added in meals. Peptide fractions from an in vitro digest of cow’s milk, separated by gel filtration, did not affect relative gene expression of DMT-1 when incubated with Caco-2 cells for 2 or 48 hours. Milk peptide fractions enhanced iron dialyzability from water by more than two fold, but not from milk or a vegetable or fruit meal. Lyophilized peptide fractions enhanced iron dialyzability from milk. Our results indicate that milk peptide fractions do not affect expression of DMT-1. Milk peptide fractions preserved their enhancing properties after in vitro digestion but did not increase iron dialyzability from milk or infant meals. Concentrated milk peptide fractions increased iron dialyzability from milk.

Last Modified: 10/24/2014