To examine the influence of inositol phosphates on the uptake and absorption of Fe and Zn, Caco-2 cells were grown on either plastic (uptake studies) or porous membranes in bicameral chambers (transport/absorption studies). Caco-2, a human colon adenocarcinoma cell line, was selected as the test cell because it spontaneously differentiates into polarized enterocyte-like cells at confluency. Uptake of Fe (added as Fe-nitrilotriacetate complex) from a calcium-free solution by fully differentiated cells was 37 pmol/cm2. Addition of 10-fold molar excess of individual inositol phosphates (IP3, IP4, IP5 or IP6) decreased Fe solubility by 13 to 25% and reduced Fe uptake by 50 to 65%. The rate of transport of Fe from the apical solution into the basolateral chamber [1.4 +/- 0.1 pmol/(h.cm2)] decreased (34-96%) in proportion to the degree of phosphorylation of the inositol derivative in the apical compartment. Uptake and transepithelial transport of Zn were 246 +/- 5 pmol/cm2 and 23 +/- 1 pmol/(h.cm2), respectively. The solubility, uptake and rate of transport of Zn also decreased in proportion to the degree of phosphorylation of inositol. These results demonstrate the inhibitory influence of IP3-IP6 on the uptake and transport of Fe and Zn and support the usefulness of the Caco-2 human cell line as an appropriate model for evaluating the effects of specific dietary factors on trace metal bioavailability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.