WATER EXTRACTS FROMNELUMBO NUCIFERALEAF REDUCED PLASMA LIPIDS AND ATHEROSCLEROSIS IN CHOLESTEROL-FED RABBITS

ABSTRACT Nelumbo nucifera Gaertn (Nelumbonaceae) leaf was used as food or beverage in Taiwan. Recently, the leaf extract was also found to possess antioxidative ability. Base on the close relationship between antioxidation and atherosclerosis, we investigated the inhibitory activity of the water extract (Nelumbo nucifera leaf extract [NLE]) on hyperlipidemia and atherosclerosis. In rabbits fed with high-cholesterol diet (HCD) plus 0.5% or 1.0% of NLE, the inhibitory level of triglyceride was 30% and 46.6%, and low-density lipoprotein cholesterol (LDL-C) was 45.4 and 45.9% compared with the HCD-fed rabbits. NLE significantly reduced severe atherosclerosis, foam cell formation and smooth muscle cell proliferation and migration in the aorta. In the thiobarituric acid-reacting substances assay, the concentration of NLE higher than 0.05 mg/mL, the inhibitory percentage was about 80%. In the relative electrophoretic mobility assay, NLE inhibited oxidative LDL up to 60%. These results suggest that NLE lowers LDL oxidation and serum lipids, and has cardiovascular protective ability. PRACTICAL APPLICATIONS The water extract of Nelumbo nucifera Gaertn (Nelumbonaceae) leaf can significantly inhibit oxidative low-density lipoprotein in vitro and reduce plasma lipid, atherosclerosis, foam cell formation, and smooth muscle cell proliferation and migration in vivo. These findings point out that the water extract of Nelumbo nucifera Gaertn (Nelumbonaceae) leaf can be applied for preventing cardiovascular diseases.