Influence of cholesterol and fat feeding on hepatic lysosomal enzymes in guinea pigs.

The activity of four lysosomal enzymes have been examined in liver cytoplasmic extract from guinea pigs fed three different diets: a) an ordinary diet, low in fat, high in carbohydrates; b) a semisynthetic diet containing 10% cottonseed oil (by weight) without and c) with 1% cholesterol. The cholesterol content in the liver was similar in control-fed and fat-fed animals, while there was a 10-fold increase in cholesterol + fat-fed animals, and most of this cholesterol was present as ester. We observed increased activity of beta-glucuronidase, beta-acetyl-glucosaminidase and cathepsin D during fat cholesterol feeding (diet c) while the activity of acid phosphatase decreased compared to control-fed animals. These findings probably mirror the increased hepatic accumulation of lipids and lipoproteins observed in cholesterol + fat-fed guinea pigs.