Effects of Glycyrrhizin and Cortisone on Cholesterol Metabolism in the Rat

Abstract

Effects of glycyrrhizin, an active principle of liquorice, on cholesterol metabolism, and its correlation with cortisone action were investigated using adrenalectomized rats. (1) Incorporation of acetate-1-14C and mevalonate-5-3H into cholesterol of liver slices was greatly stimulated by glycyrrhizin pretreatment, i. e., 1-10 mg esp. 1mg per 100g body weight per day intramuscularly for 5 days. Combined administration of glycyrrhizin with cortisone even weakened the stimulatory action of glycyrrhizin, although cortisone itself had a stimulatory action on cholesterogenesis. (2) Direct addition of glycyrrhizin in vitro to the incubation media containing liver slices of normal rats also increased cholesterogenesis at the concentration of 10-5-10-3M. (3) Excretion of intravenously injected cholesterol-4-14C into bile of bile duct-cannulated rats was much accelerated by glycyrrhizin pretreatment, 2 mg per 100g body weight per day intramuscularly for 5 days. Rates of increase of radioactivities excreted into bile by glycyrrhizin pretreatment were 4.5 times, taurocholic acid; 2.8 times, taurochenodeoxycholic acid; 2.7 times, cholesterol; and 3.7 times, total 14C, respectively. (4) Fecal excretion of intraperitoneally injected cholesterol-4-14C was also stimulated by glycyrrhizin pretreatment. Total 14C and total bile acids-14C were increased up to about 2 times, while non-saponifiable materials-14C and 3β-OH-sterols-14C remained within 1.5 times. (5) Elimination of intravenously injected cholesterol-4-14C from plasma was accelerated by glycyrrhizin injection. (6) Glycyrrhizin treatment reduced plasma cholesterol and triglycerides levels of cholesterol diet fed rats. © 1970, The Japan Endocrine Society. All rights reserved.