Phospholipid, Oleic Acid Micelles and Dietary Olive Oil Influence the Lutein Absorption and Activity of Antioxidant Enzymes in Rats

This study reports on the results of repeated
gavages and dietary feeding of lutein dispersed either in
phospholipids or fatty acid micelles or vegetable oils and
the effects on lutein bioavailability and antioxidant
enzymes in rats. For the gavage study, rats (n = 5/group)
were intubated with lutein solubilized either in oleic acid
(OLA, 18:1n-9) or linoleic acid (LNA, 18:2n-6) or phosphatidylcholine
(PC) or lysophosphatidylcholine (LPC) or
no phospholipid (NoPL) micelles for 10 days. For the
dietary study, rats (n = 5/group) were fed a diet containing
fenugreek leaf (lutein source), either with olive (OO) or
sunflower (SFO) or groundnut (GNO, control) oil or
L-a-lecithin (PL) for 4 weeks. The gavage study showed
that the plasma, liver and eye lutein levels in OLA and LPC
groups were higher by 23.9, 20.8 and 25.5% and 16.1, 28.5
and 14.0% than LNA and PC groups, respectively. The
dietary study showed the plasma (35.0 and 43.5%) and eye
(18.5 and 37.0%) lutein levels in OO were higher than SFO
and GNO groups. The plasma and eye lutein levels in the
PL group were higher by 20 and 31.3% than in the control.
It is evident that OO and PL modulate lutein absorption,
which in turn modulates antioxidant enzymes and fatty
acids in plasma and tissues compared to SFO. Hence,
selection of the fat source may be vital to enhancing the
lutein bioavailability.