Inhibition of human low density lipoprotein and high density lipoprotein oxidation by oligostilbenes from rhubarb.
The objective of the present study was to elucidate the beneficial properties of ampelopsine B (1) and epsilon-Viniferin (2), two oligostilbenes isolated from rhubarb, toward cardiovascular disease by protecting human lipoproteins against lipid peroxidation. In low density lipoprotein (LDL) oxidation, both 1 and 2 exert an inhibitory activity against Cu(2+)-, 2,2'-azobis-(2-amidinopropane) hydrochloride (AAPH)-induced, as exhibited by prolongation of lag time from 52 to 118 and 136 min, respectively, and also increasing the lag time 38 to 105 and 128 min in high density lipoprotein (HDL) oxidation for 1 and 2, respectively, at the concentration of 3.0 microM. In generation of thiobarbituric acid reactive substances (TBARS), compounds 1 and 2 inhibited LDL oxidation mediated by either catalytic Cu(2+) or thermo-labile radical initiator (AAPH) in a dose-dependent manner with IC(50) values of 3.6 and 6.0 microM for 1, and 1.7 and 3.2 microM for 2, respectively. In addition, compounds 1-2 also showed strong ability to protect HDL oxidation induced by both Cu(2+) and AAPH with low IC(50) values. The results suggest that oligostilbenes 1-2 may have a role in preventing lipoprotein oxidation.
Ngoc
Tran Minh
TM
College of Pharmacy, Chungnam National University, Daejeon, Korea.
Hung
Tran Manh
TM
Thuong
Phuong Thien
PT
Na
MinKyun
M
Kim
HongJin
H
Ha
Do Thi
do T
Min
Byung-Sun
BS
Minh
Pham Thi Hong
PT
Bae
KihWan
K