OBJECTIVETo investigate of antiatherogenic effect and possible mechanisms of piper longuminine.

METHODThe atherosclerotic model was established by the hypercholesterol feeding rabbits. Male Mew Zealand rabbits were randomly divided into five groups: normal group, model group, the high-dose (5 mg x kg(-1) x d(-1)) and low-dose (2.5 mg x kg(-1) x d(-1) group of piperlonguminine, and simvastatin group (5 mg x kg(-1) x d(-1)). All the rabbits were fed for 60 days. Blood samples were taken from the ear edge vein of rabbits in the day before the experiment, and in the days of 20, 40 and 60 days after the experiment, respectively. All the rabbits were fasted for at least twelve hours before the blood was taken. The blood serum were analyzed for total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The blood serum of the 60th day were also analyzed for superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO). At last, the pathological observation of aorta and heart samples were carried out.

RESULTCompared with those in model group, the TC, TG and LDL-C levels were reduced (P < 0.05) and the HDL-C was raised in the piperlonguminine group; also, the serum SOD and NO level was raised (P < 0.05), MDA level was reduced in the piperlonguminine group (P < 0.05). Area percentage of aorta plaque was reduced (P < 0.01) in the piperlonguminine group. The aorta and heart injury was abated and coronary artery angusty extent was markedly abatement (P < 0.01). The results of observation through transmission electron microscope (TEM) indicated that the fine structure of aortal pathological degree was markedly abated.

CONCLUSIONThe piperlonguminine could inhibit the atherogenesis formation and development, which might be due to regulating the lipid metabolism and enhancing the antioxidation.