Preterm pigs fed donor human milk have greater liver beta-carotene concentrations than pigs fed infant formula

Authors: MORAN, NANCY - Children'S Nutrition Research Center (CNRC); WADE, JOSHUA - Children'S Nutrition Research Center (CNRC); STROH, RACHEL - Baylor College Of Medicine; STOLL, BARBARA - Children'S Nutrition Research Center (CNRC); GUTHRIE, GREGORY - Children'S Nutrition Research Center (CNRC); HAIR, AMY - Baylor College Of Medicine; Burrin, Douglas - Doug

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/23/2023
Publication Date: 9/4/2023
Citation: Moran, N.E., Wade, J., Stroh, R., Stoll, B., Guthrie, G., Hair, A.B., Burrin, D.G. 2023. Preterm pigs fed donor human milk have greater liver beta-carotene concentrations than pigs fed infant formula. Journal of Nutrition. https://doi.org/10.1016/j.tjnut.2023.08.026.
DOI: https://doi.org/10.1016/j.tjnut.2023.08.026

Interpretive Summary: Carotenoids are a class of plant compounds that support vitamin A requirements and are associated with healthy functioning. Milk-fed infants receive dietary carotenoids from human milk, human donor milk, and infant formula containing added carotenoids. Infants who consume human milk often have higher amounts of carotenoids in their blood and tissues, but the reasons for this are unclear. We sought to determine if milk carotenoids are well absorbed by a piglet model of infant nutrition and if donor human milk fed piglets have greater blood and tissue concentrations of carotenoids than infant formula fed piglets. Piglets were fed donor human milk or infant formula providing equal amounts of beta-carotene for 5 days. Donor human milk-fed piglets had higher liver concentrations of beta-carotene at the end of the study, but plasma beta-carotene concentrations were equal between groups. Intestinal expression of two genes involved in carotenoid absorption were different between the groups. These findings support the hypothesis that milk carotenoid accumulation is greater with human milk feeding than with formula feeding. Future research may investigate the specific milk components responsible for differences in carotenoid accumulation in tissues.

Technical Abstract: Milk carotenoids may support preterm infant health and neurodevelopment. Infants fed human milk often have higher blood and tissue carotenoid concentrations than infants fed carotenoid-containing infant formula (IF). Donor human milk (DHM) is a supplement to mother's own milk, used to support preterm infant nutrition. We tested whether tissue and plasma beta-carotene concentrations in preterm pigs would be greater when fed pasteurized DHM versus premature infant formula (IF). This is a secondary analysis of samples collected from a study of the effects of enteral diet composition on necrotizing enterocolitis incidence. Preterm pigs received partial enteral feeding of either DHM (n=7) or premature IF (n=7) from 2-7 days of age. The diets provided similar beta-carotene (32 nM), but DHM had greater lutein, zeaxanthin, and lycopene, while IF had greater total vitamin A. Plasma, liver, and jejunum carotenoid and vitamin A concentrations were measured by HPLC-PDA. Jejunal expression of 12 genes associated with carotenoid and lipid metabolism were measured. Liver beta-carotene concentrations were greater in DHM- than IF-fed piglets (23+/-4 vs 16+/-2 ug/g, respectively, P=0.0024), while plasma and jejunal beta-carotene concentrations were similar between diets. Liver vitamin A stores were higher in piglets fed IF than DHM (50.6+/-10.1 vs. 30.9+/-7.2 ug/g, respectively, P=0.0013), however, plasma vitamin A was similar between groups. Plasma, liver, and jejunum concentrations of lutein, zeaxanthin, and lycopene were higher with DHM than IF feeding. Relative to piglets fed DHM, jejunal low density lipoprotein receptor (Ldlr) expression was higher (61%, P=0.018) and cluster determinant 36 (Cd36) expression (-27%, P=0.034) was lower in IF-fed piglets. Preterm pigs fed DHM accumulated more liver beta-carotene than IF-fed pigs. Future studies should further investigate infant carotenoid bioactivity and bioavailability.