title: Antioxidant activity of cleomiscosins A and C isolated from Acer okamotoanum.
abstract: Phytochemical investigation of Acer okamotoanum leaf and twig led to the isolation of two coumarinolignans, cleomiscosin A (1) and cleomiscosin C (2). Here, we found that 2 dose-dependently inhibits LDL oxidation mediated by either catalytic copper ions (Cu2+) or free radicals generated with the azo compound 2,2'-azobis-(2-amidinopropane)dihydro-chloride (AAPH) with IC50s of 29.5 and 11.9 microM, respectively. By electrophoretic analysis, we also observed that 2 protects apolipoprotein B-100 (apoB-100) against Cu2+-induced fragmentation (65.3% inhibition at 5 microM). Furthermore, fluorescence analyses clearly indicated that both 1 and 2 protect against the oxidative modification of apoB-100 induced by either Cu2+ or HOCl (1, IC50s of 13.4 and 8.1 microM, respectively; 2, IC50s of 23.6 and 3.9 microM, respectively). These findings suggest that 1 and 2 could be beneficial in preventing LDL oxidation in atherosclerotic lesions.
authors.affiliation: College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
authors.forename: WenYi
authors.initials: W
authors.lastname: Jin
authors.forename: Phuong Thien
authors.initials: PT
authors.lastname: Thuong
authors.forename: Nguyen Duy
authors.initials: ND
authors.lastname: Su
authors.forename: Byung Sun
authors.initials: BS
authors.lastname: Min
authors.forename: Kun Ho
authors.initials: KH
authors.lastname: Son
authors.forename: Hyeun Wook
authors.initials: HW
authors.lastname: Chang
authors.forename: Hyun Pyo
authors.initials: HP
authors.lastname: Kim
authors.forename: Sam Sik
authors.initials: SS
authors.lastname: Kang
authors.forename: Dai Eun
authors.initials: DE
authors.lastname: Sok
authors.forename: KiHwan
authors.initials: K
authors.lastname: Bae
mesh_terms: D031002:Acer / Q000737:chemistry*; D000975:Antioxidants / Q000302:isolation & purification* / Q000494:pharmacology; D003374:Coumarins / Q000302:isolation & purification* / Q000494:pharmacology; D004146:Dioxanes / Q000302:isolation & purification* / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D008077:Lipoproteins, LDL / Q000378:metabolism; D010084:Oxidation-Reduction
chemical_list: D000975:Antioxidants; D003374:Coumarins; D004146:Dioxanes; D008077:Lipoproteins, LDL; C438427:cleomiscosin C; C041934:cleomiscosin A