Lutein supplementation leads to decreased soluble complement membrane attack complex sC5b-9 plasma levels

PurposeThe purpose of this study was to investigate the effect of lutein on systemic complement activation in elderly individuals. MethodsSeventy patients with signs of early age-related macular degeneration (AMD) were included in this study. All subjects were randomly assigned to receive a 10mg daily dose of lutein or a placebo for a time period of 1year. EDTA blood was collected before and at various time-points during the study (0, 4, 8 and 12months). The plasma level of the soluble complement membrane attack complex sC5b-9 was measured by ELISA. ResultsWe found a significant 1.1ng/ml monthly decrease in the plasma sC5b-9 concentration in the lutein group (p<0.001), resulting in a decrease from 60.3ng/ml at baseline to 46.3ng/ml at 12months. For the placebo group, we found a significant 0.6ng/ml monthly increase in plasma sC5b-9 concentration (p=0.001), resulting in an increase from 51.6ng/ml at baseline to 58.4ng/ml at 12months. ConclusionsLutein supplementation inhibits the systemic activation of the complement system, which provides further functional evidence for the reported beneficial effects of this carotenoid in the management of AMD.