The MeOH extract of Pleurospermum kamtschaticum and its active component buddlejasaponin (IV) inhibits intrinsic and extrinsic hyperlipidemia and hypercholesterolemia in the rat

Abstract

The inhibitory effect of the MeOH extract of Pleurospermum kamtschaticum (Umbelliferase) and its fractions were tested in hyperlipidemic and hypercholesterolemic rats using four animal models induced using poloxamer-407 or using Triton WR-1339 as intrinsic inducers and by 30% corn oil or high cholesterol diet as extrinsic inducers. We measured serum triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol levels as measures of its hypocholesterolemic or hypolipidemic effects. Since the MeOH extract and the BuOH fraction of Pleurospermum kamtschaticum were found to be active using these four hypolipidemic assays, its major saponin buddlejasaponin IV {BS(IV)} isolated from the BuOH fraction were also tested to demonstrate the active components. BS(IV) was found to significantly inhibit hypercholesterolemia and hyperlipidemia by extrinsic and intrinsic inducers. In particular, BS(IV) reduced the blood thiobarbituric acid reactive substance (TBARS) and hydroxy radical levels, and increased superoxide dismutase activity in high cholesterol diet-induced rats, thus suggesting that BS(IV) reduces oxidative stress caused by a high cholesterol diet. Moreover, these effects of BS(IV) were comparable to probucol, which was used as a positive control. These results suggested that Pleurospermum kamtschaticum which is traditionally used to treat atherosclerosis and its active major saponin BS(IV) could be used to treat hypercholesterolemia or hyperlipidemia.