Lipid profile interactions in subjects with atherosclerosis

While widely known for its provitamin A activity and role in vision, beta-carotene also serves as a potent lipophilic antioxidant.

Scope of the Study

This trial specifically enrolled 60 subjects with documented early-stage atherosclerosis and elevated baseline oxidized LDL (oxLDL) levels.

Participants consumed a daily dosage of natural mixed carotenoids for 12 weeks.

Findings

1. oxLDL Reduction: A statistically significant reduction in circulating oxLDL levels was observed by week 8, sustained through week 12 (p < 0.05).
2. Lipid Profile Shift: While total cholesterol levels remained largely unaffected, there was a minor but consistent increase in the HDL to LDL ratio.
3. Endothelial Function: Flow-mediated dilation (FMD) showed a positive trending improvement, though it did not reach definitive statistical significance within the 12-week timeframe.

Discussion

The presence of the 9-cis stereoisomer appears to offer enhanced protection to lipid membranes against free radical attack, likely due to its unique structural conformation, which spans the phospholipid bilayer differently than the rigid all-trans molecule.