Phospholipids Affect the Intestinal Absorption of Carotenoids in Mice

Previously, we have shown that uptake of carotenoids
solubilized with mixed micelles by human intestinal
Caco-2 cells is enhanced by lysophosphatidylcholine (lysoPC)
and suppressed by PC. This study determined the effect of PC
and lysoPC in mixed micelles on the accumulation of β-carotene
and lutein in mice in order to elucidate the roles of micellar
phospholipid in the intestinal uptake of carotenoids in vivo.
Mixed micelles were composed of 2.5 mM monooleoylglycerol,
7.5 mM oleic acid, 12 mM sodium taurocholate, 200 μM
carotenoid, and 3 mM phospholipid in PBS. The mice were fed
single doses of β-carotene or lutein solubilized in PC (PC group),
lysoPC (LPC group), and no phospholipid (NoPL group) micelles.
The β-carotene responses in the plasma and liver of the PC group
were markedly lower than those of the other two groups,
whereas no differences were noticed between the LPC and NoPL
groups. The average level of lutein in the plasma of the PC group
after administration was significantly (P < 0.05) lower than those
of the other groups. Moreover, the average level of lutein in the
liver was significantly (P < 0.05) different among the groups in
the order of LPC > NoPL >PC. Thus, the results clearly indicate
that PC suppressed the accumulation of β-carotene and lutein in
plasma and liver and that lysoPC enhanced the accumulation of
lutein in liver. These results suggest that the hydrolysis of PC to
lysoPC plays an important role in the intestinal uptake of
carotenoids solubilized in mixed micelles.