Effects of new combinative antioxidant FeAOX-6 and alpha-tocotrienol on macrophage atherogenesis-related functions.
Pivotal role in atherogenesis is played by macrophages, which are early site for lipid accumulation and mediate the inflammatory and immune response in the intima. Epidemiological evidence indicates that natural antioxidants reduce the risk of heart disease, but, so far, supplementation studies have failed to confirm any protective effects of these compounds against cardiovascular disease. This study evaluated the effects of the natural antioxidant alpha-tocotrienol and of the newly designed compound, FeAOX-6, which combines antioxidant structural features of both tocopherols and carotenoids into a single molecule, on macrophage functions involved in foam cell formation. FeAOX-6 or alpha-tocotrienol induce a strong dose-dependent reduction of cholesterol and reduce cholesterol accumulation in human macrophages. The extent of the reduction found with alpha-tocotrienol was greater than that induced by FeAOX-6 and did not correlate with their respective antioxidant capacities. Treatment of HMDM with alpha-tocotrienol or FeAOX-6 enhanced also tumor necrosis factor-alpha secretion. These results are consistent with a reduction in scavenger receptor activity, but we found that antioxidant treatment did not affect cholesterol uptake from modified LDL. The effects on release on pro-inflammatory prostanoid precursors, PGE(2) and cytokine suggest a variety of metabolic responses that are both dependent on antioxidant compounds and macrophages activation status.
Napolitano
Mariarosaria
M
Department of Haematology, Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161 Rome, Italy.
Avanzi
Luca
L
Manfredini
Stefano
S
Bravo
Elena
E
D000975:Antioxidants / Q000494:pharmacology*; D016718:Arachidonic Acid / Q000378:metabolism; D050197:Atherosclerosis / Q000378:metabolism*; D002478:Cells, Cultured; D002784:Cholesterol / Q000378:metabolism; D002788:Cholesterol Esters / Q000378:metabolism; D002839:Chromans / Q000494:pharmacology*; D016207:Cytokines / Q000378:metabolism; D015237:Dinoprost / Q000031:analogs & derivatives / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005487:Foam Cells / Q000187:drug effects / Q000378:metabolism; D005609:Free Radicals / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D051116:Receptors, Scavenger / Q000187:drug effects / Q000378:metabolism; D024508:Tocotrienols; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000494:pharmacology
D000975:Antioxidants; D002788:Cholesterol Esters; D002839:Chromans; D016207:Cytokines; C480763:FeAOX-6; D005609:Free Radicals; D051116:Receptors, Scavenger; D024508:Tocotrienols; D014810:Vitamin E; C075750:8-epi-prostaglandin F2alpha; D016718:Arachidonic Acid; D002784:Cholesterol; C082032:tocotrienol, alpha; D015237:Dinoprost; D015232:Dinoprostone