Iron Chlorophyllin Bio-efficacy and Metabolites Following Simulated Digestion and Incubation with Caco-2 cells

Developing countries rely on poorly bioavailable plant-based sources of iron (i.e.FeSO4), leading to iron deficiency anemia. Heme iron is more bioavailable, but predominantly found in red meat. Iron chlorophyllin (IC) utilizes the porphyrin ring of plant-based chlorophyll to bind iron. IC has previously been shown to deliver iron to cells. However, the dose-response of IC treatment has not been assessed.
We hypothesized that increasing IC concentrations would increase cellular iron in a dose dependent manner. We also hypothesized that novel IC metabolites would be observed following in vitro digestion and incubation with Caco-2 cells.
In vitro digestion was performed using FeSO4 and hemoglobin as positive controls, deionized water as a negative control, and IC as the treatment. Digested chyme was centrifuged and filtered before incubation with differentiated Caco-2 human intestinal cells for 4 h. Iron concentrations in the chyme, micelles and harvested cells were tested using furnace atomic absorption spectrometry, and concentrations compared using one-way ANOVA, followed by Tukey’s post-hoc test (P < 0.05). Metabolites of IC following digestion and cell incubation were tested using UHPLC-DAD-HRMS.
IC delivered as much iron to the cells as heme, and trended toward increased iron delivery relative to FeSO4 (P = 0.068) when comparing across the low dose concentrations. Following digestion, Fe-chlorin e4 and e6 were totally converted to IC derivatives. Dehydrogenated and demethylated IC metabolites were detected in the cell. Results suggest that IC may better deliver iron to Caco-2 cells as compared to FeSO4, and should be further explored for iron supplementation.