Impaired uptake of β-carotene by Caco-2 human intestinal cells in the presence of iron

Abstract

At present, there are conflicting data regarding whether or not β-carotene has a positive effect on iron absorption. This study was undertaken to evaluate possible interactions involved in the uptake of β-carotene and iron in a human intestinal cell model (Caco-2). The Caco-2 cells were incubated with test solutions containing different amounts of ferrous chloride (10–50 µM) and β-carotene (0.3–2.5 µM) incorporated in synthetic micelles. In the absence of iron, cellular accumulation of β-carotene from synthetic micelles was proportional (r²=0.97, P <0.001) to the β-carotene concentration in the test solution. However, with addition of ferrous chloride (30 µM), the β-carotene uptake was significantly reduced (P <0.05), on average by 22%. There was also an inverse relationship between the β-carotene uptake and iron concentration in the test solution (r²=0.93, P <0.05). Iron provided in physiological amounts inhibited the uptake of β-carotene in the in vitro Caco-2 cell system.

• Caco-2 cells
• β-carotene
• iron uptake
• micelles
• ferritin
• high-performance liquid chromatography