The antiatherogenic effect of allicin: possible mode of action.
OBJECTIVE
Garlic (Allium sativum) has been suggested to affect several cardiovascular risk factors. Its antiatherosclerotic properties are mainly attributed to allicin that is produced upon crushing of the garlic clove. Most previous studies used various garlic preparations in which allicin levels were not well defined. In the present study, we evaluated the effects of pure allicin on atherogenesis in experimental mouse models.


RESULTS
Daily dietary supplement of allicin, 9 mg/kg body weight, reduced the atherosclerotic plaque area by 68.9 and 56.8% in apolipoprotein E-deficient and low-density lipoprotein (LDL) receptor knockout mice, respectively, as compared with control mice. LDL isolated from allicin-treated groups was more resistant to CuSO(4)-induced oxidation ex vivo than LDL isolated from control mice. Incubation of mouse plasma with (3)H-labeled allicin showed binding of allicin to lipoproteins. By using electron spin resonance, we demonstrated reduced Cu(2+) binding to LDL following allicin treatment. LDL treatment with allicin significantly inhibited both native LDL and oxidized LDL degradation by isolated mouse macrophages.


CONCLUSIONS
By using a pure allicin preparation, we were able to show that allicin may affect atherosclerosis not only by acting as an antioxidant, but also by other mechanisms, such as lipoprotein modification and inhibition of LDL uptake and degradation by macrophages.
Institute of Lipid and Atherosclerosis Research, Sheba Medical Center, Tel Hashomer, Israel.
Ayelet
A
Gonen
Dror
D
Harats
Aharon
A
Rabinkov
Talia
T
Miron
David
D
Mirelman
Meir
M
Wilchek
Lev
L
Weiner
Esfir
E
Ulman
Hana
H
Levkovitz
Dikla
D
Ben-Shushan
Aviv
A
Shaish
D000818:Animals; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D001011:Aorta / Q000473:pathology; D001057:Apolipoproteins E / Q000172:deficiency; D001161:Arteriosclerosis / Q000097:blood / Q000235:genetics* / Q000473:pathology*; D002784:Cholesterol / Q000097:blood; D002853:Chromatography, Liquid; D004220:Disulfides; D004578:Electron Spin Resonance Spectroscopy; D006801:Humans; D000960:Hypolipidemic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D008077:Lipoproteins, LDL / Q000097:blood; D017737:Macrophages, Peritoneal / Q000187:drug effects; D051379:Mice; D018345:Mice, Knockout; D010084:Oxidation-Reduction; D011973:Receptors, LDL / Q000172:deficiency; D013441:Sulfinic Acids / Q000302:isolation & purification / Q000494:pharmacology*
D000975:Antioxidants; D001057:Apolipoproteins E; D004220:Disulfides; D000960:Hypolipidemic Agents; D008077:Lipoproteins, LDL; D011973:Receptors, LDL; D013441:Sulfinic Acids; C006452:allicin; D002784:Cholesterol