Effect of tincture of Crataegus on the LDL-receptor activity of hepatic plasma membrane of rats fed an atherogenic diet.

Tincture of Crataegus, (TCR), is a hypocholesterolemic and antiatherosclerotic drug made from berries of hawthorn, Crataegus oxyacantha. Its main constituents are flavonoids, triterpene saponins and a few cardioactive amines. TCR, when administered simultaneously to rats fed an atherogenic diet, significantly increased the binding of 125I-LDL to the liver plasma membranes, in vitro. Scatchard analysis of the specific binding data revealed that under the influence of TCR treatment the liver membranes bound to a greater number of 125I-LDL molecules indicating an enhancement in the LDL-receptor activity. TCR was also shown to increase bile acid excretion and to depress hepatic cholesterol synthesis in atherogenic diet fed rats. With these observations in view, the hypocholesterolemic action of TCR appears to be due to an upregulation of hepatic LDL-receptors resulting in greater influx of plasma cholesterol into the liver. TCR also prevents the accumulation of cholesterol in the liver by enhancing cholesterol degradation to bile acids and by simultaneously suppressing cholesterol biosynthesis. The various constituents of TCR may act synergistically to bring about the observed effects.