Alpha tocopherol supplementation elevates plasma apolipoprotein A1 isoforms in normal healthy subjects

Area of Science:

• Nutritional Science
• Proteomics
• Cardiovascular Health

Background:

• Plasma alpha-tocopherol (AT) concentrations correlate inversely with cardiovascular (CV) risk.
• Previous AT intervention studies have not consistently demonstrated CV disease (CVD) benefits.
• Proteomics can reveal novel effects of AT on protein expression and physiological roles.

Purpose of the Study:

• To investigate the impact of AT supplementation on the plasma proteome in healthy individuals.
• To explore the dose- and time-dependent effects of AT on specific plasma proteins.
• To understand the physiological mechanisms underlying AT's potential CV effects.

Main Methods:

• A double-blind, randomized, parallel-design study involving 32 healthy subjects.
• Administration of AT supplements (134 or 268 mg/day) or placebo for up to 28 days.
• Plasma proteome analysis using 2-DE and MALDI-MS, with validation by Western blotting and ELISA.

Main Results:

• Semiquantitative proteomics identified altered proapolipoprotein A1 levels (at least two-fold change).
• Quantitative ELISA confirmed a significant, time- and dose-dependent increase in plasma apolipoprotein A1 concentration with AT supplementation.
• The increase in apolipoprotein A1 was statistically significant (p < 0.01) after 28 days with 268 mg/day AT.

Conclusions:

• Plasma proteome is sensitive to AT supplementation in a time- and dose-dependent manner.
• AT supplementation significantly increases plasma apolipoprotein A1 levels in healthy adults.
• These findings provide insights into the physiological roles of AT and its potential impact on cardiovascular health.