Biosynthesis of glycoproteins in the intestinal mucosa. II. Influence of diets.
To determine the effect of diets on the biosynthesis of glycoproteins in the intestinal mucosa, male Sprague-Dawley rats were fed, ad libitum, high-carbohydrate high-fat and high-protein diets. In in vivo methodology, the animals from each dietary group received an intraperitoneal injection of [14C]-fucose, or [14C]-galactose or [14C]-glucosamine. Incorporated radioactivity was detected in the different subcellular fractions. In in vitro methodology, five glycosyl-transferases were studied on microsomes and cell sap. In vivo, only the high-fat diet induces a decrease in the incorporation of [14C]-glucosamine in the macromolecules. In vitro, only the fucosyl-transferase activity is modified by several diets: as compared with an increase in the activity of the control with the age of the animals, high-protein diet induces a slight activation after 2 weeks of diet, while high-carbohydrate and particularly high-fat diets inhibit the enzyme activity. The inhibition is the same when high-fat diet consists of either oil mixture or triolein or oleic acid or linoleic acid and becomes significant with a supplementation rate of 10%.
D000818:Animals; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D005647:Fucosyltransferases / Q000032:analysis; D006023:Glycoproteins / Q000096:biosynthesis*; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D008861:Microsomes / Q000201:enzymology; D051381:Rats; D011919:Rats, Inbred Strains
D004040:Dietary Carbohydrates; D004041:Dietary Fats; D006023:Glycoproteins; D005647:Fucosyltransferases