EFFECT OF THE PURIFIED UNSAPONIFIABLE FRACTION OF SOYBEAN ON THE LIPID METABOLISM AND GALLSTONE IN MICE

The influences of the purified unsaponifiable fraction of soybean (PUFS) on gallstone formation and dissolution and related lipid metabolism were investigated in mice fed lithogenic diet in comparison with soybean sterols (SBST).　　In experiment I, the effect of each drug on gallstone formation was studied during 8 weeks. All of mice fed lithogenic diet had a large number of gallstones in gallbladder but PUFS treatment inhibited markedly the stone production. The influence of SBST alone was weaker than PUFS itself. In this experiment, the serum and liver cholesterol levels were parallel to the degree of gallstone production. The liver enlarged three times as large as control under the lithogenic condition was improved with PUFS or SBST. In experiment II, the effect of drugs on gallstone dissolution was investigated. The mice already having gallstone after feeding a lithogenic diet for 8 weeks were kept on the normal chow with or without PUFS for further 5 weeks. The tendency to dissolve gallstone was not observed in both groups but serum and liver cholesterol contents and liver weight returned more rapidly to normal level in the PUFS treated group. As experiment III, the mice already having gallstone were continuously maintained on the lithogenic diet with or without PUFS during 6 weeks. No effect on gallstone dissolution was found but the desirable influences on lipid metabolism were also clearly observed.