Enhanced lutein bioavailability by lyso-phosphatidylcholine in rats

Area of Science:

• Nutritional biochemistry
• Gastrointestinal physiology
• Lutein bioavailability

Background:

• Lutein, a vital carotenoid, requires solubilization for optimal absorption.
• Mixed micelles are essential delivery vehicles for lipophilic compounds like lutein.
• The role of specific phospholipids, phosphatidylcholine (PC) and lysophosphatidylcholine (lysoPC), in lutein micellar solubilization and absorption is not fully understood.

Purpose of the Study:

• To evaluate the impact of phosphatidylcholine (PC) versus lysophosphatidylcholine (lysoPC) on lutein bioavailability in male rats.
• To determine the influence of single versus repeated dosing on lutein absorption mediated by different micellar compositions.

Main Methods:

• Male rats were administered lutein solubilized in mixed micelles containing either PC, lysoPC, or no phospholipids (NoPL).
• Single and repeated dose experiments were conducted over 9 hours and 10 days, respectively.
• Lutein levels in plasma and liver, as well as urinary and fecal excretion, were measured.

Main Results:

• In single-dose studies, PC significantly suppressed lutein uptake, with absorption order: lysoPC > NoPL > PC.
• Repeated dosing showed a different pattern: lysoPC > PC > NoPL, indicating PC's suppressive effect diminished over time.
• Higher lutein excretion was observed in the PC group, and lysoPC consistently enhanced plasma and liver lutein levels.

Conclusions:

• Lysophosphatidylcholine (lysoPC) enhances lutein absorption from mixed micelles.
• Phosphatidylcholine (PC) can suppress lutein intestinal uptake, particularly after a single dose.
• Luminal hydrolysis of PC to lysoPC appears necessary for efficient lutein intestinal uptake from mixed micelles.