Effect of Elastase on Cholesterol Metabolism

Abstract

Elastase (30% or 50%, namely 12 or 20 unit/mg by Sachar's method) and mice were used. The following results were obtained.
A. Blood total cholesterol: When normal animals were injected at a rate of 1mg/kg/day for 15 days, no changes were seen, while cholesterol or puromycin induced hypercholesterolemia were inhibited by the joint usage of administration of elastase.
B. Biosynthesis of liver cholesterol in vitro and in vivo: Addition of elastase to liver homogenate inhibited the incorporation of both acetate-¹⁴C and mevalonate-¹⁴C into cholesterol. As regards the biosynthesis of liver cholesterol in the case of injection of elastase, the incorporation of acetate-¹⁴C increased, while the incorporation into cholesterol from mevalonate-¹⁴C showed no changes.
C. The decrease of cholesterol induced liver oxygen consumption was inhibited by the administration of elastase.
D. The intestinal absorption of cholesterol-4-¹⁴C showed no changes by the administration of elastase.
E. Total activity in bile comming from cholesterol-4-¹⁴C administration increased in animals injected with elastase at a rate of 4mg/kg/day for 5 days.
F. The oxidation of cholesterol-26-¹⁴C by liver mitochondria increased by administration of elastase.
G. The excretion of total bile acid-¹⁴C in faeces after cholesterol-4-¹⁴C administration increased in both normal and cholesterol fed animals by administration of elastase.
From the above data it may be said that the blood cholesterol-lowering act of elastase appers to be due mainly the increase of the catabolism of cholesterol and fecal excretion of bile acids.