Dephosphorylation of myo-inositol phosphates in the in vitro intestinal Caco-2 cell model.

International journal of food sciences and nutrition

PubMedID: 28554270

Briviba K, Schollenberger M, Rodehutscord M, Greiner R. Dephosphorylation of myo-inositol phosphates in the in vitro intestinal Caco-2 cell model. Int J Food Sci Nutr. 2017;1-6.
Plant and microbial phytases present in raw materials can cause a dephosphorylation of phytate (myo-inositol hexakisphosphate) (InsP6)) during food processing resulting in a broad range of different myo-inositol phosphates such as pentakisphosphate (InsP5) and tetrakisphosphate (InsP4) in foods. Here, we investigated whether the human intestinal epithelium is able to dephosphorylate myo-inositol phosphates (InsP6, InsP5-, InsP4-, InsP3-isomers) using an in vitro model with differentiated human Caco-2 cells cultured on semipermeable inserts. Incubation of InsP6 and an InsP5-isomer with cells for 3?h showed no dephosphorylation of both InsPs. Treatment of cells with a mixture of different InsP4-isomers, however, caused a formation of about 3. 5% of an InsP3-isomer (Ins(1,5,6)P3) and treatment with a mixture of different InsP3-isomers caused about 20% formation of InsP2-isomers, respectively. Thus, human intestinal cells can contribute to the dephosphorylation of myo-inositol phosphates of partly dephosphorylated forms such as InsP3 and InsP4.