Inhibitory effects of an aqueous extract of Apocynum venetum leaves and its constituents on Cu(2+)-induced oxidative modification of low density lipoprotein.
An aqueous extract of Apocynum venetum leaves and its constituents inhibited thiobarbituric acid reactive substances (TBARS) and conjugated-diene formation in the Cu(2+)-induced oxidation of low density lipoprotein (LDL) in vitro. The TBARS formation was most strongly inhibited by chlorogenic acid with an IC(50) value of 1.9 microM, but other constituents were in a range of 2.3-23.3 microM. On the other hand, the lag time in the conjugated-diene formation was dose-dependently prolonged by addition of the aqueous extract. Catechin prolonged the lag time more than 300 min and other constituents such as chlorogenic acid, epicatechin, epigallocatechin, hyperoside and isoquercitrin led to no conjugated-diene formation within 700 min under the experimental conditions.
Kim
D W
DW
Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan.
Yokozawa
T
T
Hattori
M
M
Kadota
S
S
Namba
T
T
D008078:Cholesterol, LDL / Q000187:drug effects* / Q000378:metabolism; D019327:Copper Sulfate / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006801:Humans; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D015227:Lipid Peroxidation / Q000187:drug effects; D010084:Oxidation-Reduction / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
D008078:Cholesterol, LDL; D004365:Drugs, Chinese Herbal; D000960:Hypolipidemic Agents; D010936:Plant Extracts; D017392:Thiobarbituric Acid Reactive Substances; D019327:Copper Sulfate