Section 9
Chapter 8,529

Effect of dietary supplementation of beta-carotene on human monocyte-macrophage-mediated oxidation of low density lipoprotein

Levy, Y.; Kaplan, M.; Ben-Amotz, A.; Aviram, M.

Israel Journal of Medical Sciences 32(6): 473-478


ISSN/ISBN: 0021-2180
PMID: 8682654
Accession: 008528960

Download citation:  

Oxidative modification of low density lipoprotein (LDL), a key step in early atherosclerosis, is protected by the lipoprotein-associated antioxidants. The present study analyzes the effect of beta-carotene in plasma, in LDL and in monocyte-macrophages, on macrophage-mediated oxidation of LDL. We investigated the effect of dietary supplementation of beta-carotene on plasma lipid peroxidation (induced by AAPH (2,2-Azobis-2-amidinopropane hydrochloride)) and on cell-free and cell-mediated oxidation of LDL by human monocyte-derived macrophages (HMDM) in the presence of CuSO-4. Significant enrichment with beta-carotene was noted in plasma (twofold), in LDL (2.6-fold) and in HMDM (1.6-fold) 2 weeks after dietary supplementation with 180 mg/day of beta-carotene. Plasma lipid peroxidation analyzed by conjugated dienes generation decreased by 22% (P lt 0.01) and LDL susceptibility to oxidation analyzed by malondialdehyde generation decreased by 40% (P lt 0.01). After beta-carotene supplementation, beta-carotene-enrichment of HMDM did not affect HMDM capacity to oxidize native LDL, whereas beta-carotene enrichment of LDL significantly reduced LDL oxidation. In conclusion, then, our results suggest that beta-carotene content of LDL, but not that of the macrophages, is responsible for the inhibition of oxidation of LDL.

PDF emailed within 1 workday: $29.90