Retinal Carotenoid Supplementation Increases HDL Cholesterol in Humans and Mice

Area of Science:

• Ophthalmology
• Nutritional Science
• Cardiovascular Health

Background:

• Age-related macular degeneration (AMD) risk is linked to HDL cholesterol levels.
• Carotenoids are dietary nutrients transported via HDL complexes to the retina.
• Understanding carotenoid effects on lipids is crucial for AMD prevention.

Purpose of the Study:

• To investigate the impact of carotenoid supplementation on circulating HDL cholesterol.
• To assess changes in other serum lipid profiles (total cholesterol, LDL, TG).
• To explore the dose-response relationship of individual carotenoids on lipid profiles.

Main Methods:

• Human trial (L-ZIP): 40 pregnant women, half received lutein/zeaxanthin, half placebo.
• Serum lipid profiles measured in pregnant women during the third trimester.
• Animal study: Macular pigment transgenic mice fed lutein, zeaxanthin, or beta-carotene for one month.

Main Results:

• Carotenoid supplementation significantly increased HDL cholesterol in pregnant women.
• No significant changes in total cholesterol, LDL cholesterol, or triglycerides were observed in the human trial.
• In mice, lutein, zeaxanthin, and beta-carotene all increased HDL cholesterol and decreased TG levels, with zeaxanthin showing the greatest effect.

Conclusions:

• Carotenoid supplementation positively modulates serum lipid profiles by increasing HDL cholesterol and decreasing TG.
• These lipid-modulating effects may contribute to the protective role of carotenoids against AMD.
• Findings support the potential of carotenoids in managing lipid-associated diseases.