Prevention of cholesterol cholelithiasis by dietary unsaturated fats in hormone-treated female hamsters.
We examined the effect of diet on gallstone incidence and the composition of biliary phosphatidylcholines in methyltestosterone-treated female hamsters. These hamsters were fed a nutritionally adequate purified lithogenic diet containing 2% corn oil, 4% butterfat, 0.3% cholesterol, and 0.05% methyltestosterone, resulting in a cholesterol gallstone incidence of 86%. This incidence was lowered when mono- and polyunsaturated fats or fatty acids were added to the diet: 2.5% oleic acid resulted in total prevention of cholesterol cholelithiasis, 2.5% linoleic acid, and 4% safflower oil (78% linoleic acid content) reduced gallstone incidence to 26 and 8%, respectively. An additional 4% butterfat (29% oleic acid content) produced gallstones in 50% of the animals. At the end of the 6-wk feeding period, the bile of all hamsters was supersaturated with cholesterol. The major biliary phosphatidylcholine species in all groups were (sn-1-sn-2): 16:0-18:2, 16:0-18:1, 18:0-18:2, 16:0-20:4, and 18:2-18:2. The safflower oil- and linoleic acid-fed hamsters exhibited an enrichment of 16:0-18:2 (16-18%); added butterfat or oleic acid increased the proportion of 16:0-18:1 (9 and 25%, respectively). We conclude that the phosphatidylcholine molecular species in female hamster bile can be altered by dietary fats/fatty acids and that mono- and polyunsaturated fatty acids play a role in suppressing the induced cholelithiasis.
Ayyad
N
N
Department of Surgery, Beth Israel Medical Center, New York, New York 10003, USA.
Cohen
B I
BI
Ohshima
A
A
Mosbach
E H
EH
D000821:Animal Feed; D000818:Animals; D001647:Bile Acids and Salts / Q000737:chemistry; D002769:Cholelithiasis / Q000737:chemistry / Q000453:epidemiology / Q000517:prevention & control*; D002784:Cholesterol / Q000032:analysis / Q000097:blood; D015331:Cohort Studies; D006224:Cricetinae; D004042:Dietary Fats, Unsaturated / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000627:therapeutic use*; D005260:Female; D005526:Food, Formulated; D015994:Incidence; D008099:Liver / Q000378:metabolism; D008647:Mesocricetus; D008777:Methyltestosterone / Q000494:pharmacology; D045165:Testosterone Congeners / Q000494:pharmacology
D001647:Bile Acids and Salts; D004042:Dietary Fats, Unsaturated; D005231:Fatty Acids, Unsaturated; D045165:Testosterone Congeners; D002784:Cholesterol; D008777:Methyltestosterone