title: Inhibitory effect of three C-glycosylflavonoids from Cymbopogon citratus (Lemongrass) on human low density lipoprotein oxidation.
abstract: This study assessed the inhibitory effect of three C-glycosylflavonoids from Cymbopogon citratus leaves--isoorientin (1), swertiajaponin (2) and isoorientin 2"-Orhamnoside (3)--on human LDL oxidation. Isolated LDL was incubated with compounds 1-3 and the kinetics of lipid peroxidation were assessed by conjugated diene and malondialdehyde-thiobarbituric acid reactive substances (MDA-TBARS) formation after addition of copper ions. Significant differences (p < 0.05) between the lag time phase of the control and the lag time phase in the presence of the compounds 1 (0.25 microM) and 2 (0.50 microM) were observed. After five hours of incubation all three compounds showed a significant inhibitory effect on MDA-TBARS formation with respect to the control. After six hours of incubation only compound 1 kept a remarkable antioxidant effect. This study demonstrates that isoorientin (1) is an effective inhibitor of in vitro LDL oxidation. As oxidative damage to LDL is a key event in the formation of atherosclerotic lesions, the use of this natural antioxidant may be beneficial to prevent or attenuate atherosclerosis.
authors.affiliation: Department of Clinical Biochemistry and Immunohematology, University of Talca, Talca, Chile. rorrego@utalca.cl
authors.forename: Roxana
authors.initials: R
authors.lastname: Orrego
authors.forename: Elba
authors.initials: E
authors.lastname: Leiva
authors.forename: José
authors.initials: J
authors.lastname: Cheel
mesh_terms: D000924:Anticholesteremic Agents / Q000737:chemistry / Q000494:pharmacology*; D008078:Cholesterol, LDL / Q000187:drug effects* / Q000378:metabolism; D031743:Cymbopogon / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects*; D047311:Luteolin / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000924:Anticholesteremic Agents; D008078:Cholesterol, LDL; D005419:Flavonoids; C546517:isoorientin 2''-O-rhamnoside; C546516:swertiajaponin; C057912:homoorientin; D047311:Luteolin