Prolonged, low dose alpha-tocopherol therapy counteracts intercellular cell adhesion molecule-1 activation

Area of Science:

• Cardiovascular Research
• Nutritional Science
• Vascular Biology

Background:

• Intercellular Adhesion Molecule-1 (ICAM-1) up-regulation promotes atherosclerosis development.
• Soluble ICAM-1 (sICAM-1) is a biomarker for endothelial activation.
• Understanding factors influencing sICAM-1 in healthy individuals is crucial for preventive cardiology.

Purpose of the Study:

• To investigate the effect of low-dose alpha-tocopherol on circulating sICAM-1 levels in healthy subjects.
• To determine if alpha-tocopherol supplementation can modulate endothelial activation markers.

Main Methods:

• A randomized, double-blind, placebo-controlled trial was conducted.
• 39 healthy male volunteers received either alpha-tocopherol (50 I.U./day) or placebo for 20 weeks.
• Plasma sICAM-1 and alpha-tocopherol concentrations were measured at baseline and after 20 weeks.

Main Results:

• Baseline sICAM-1 levels were inversely correlated with alpha-tocopherol concentrations.
• Alpha-tocopherol supplementation significantly decreased sICAM-1 levels (p<0.004) and increased alpha-tocopherol levels (p<0.003).
• No significant changes were observed in the placebo group; changes in sICAM-1 correlated inversely with changes in alpha-tocopherol (r=-0.597, p=0.005).

Conclusions:

• Plasma sICAM-1 concentrations are stable in healthy individuals over 20 weeks.
• Low-dose alpha-tocopherol effectively reduces circulating sICAM-1 levels in healthy men.
• Antioxidant vitamins like alpha-tocopherol may counteract endothelial changes contributing to atherogenesis.