title: Intestinal apolipoprotein B-48 synthesis and lymphatic cholesterol transport are lower in swine fed high fat, high cholesterol diet with soy protein than with casein.
abstract: Effects of dietary proteins on intestinal lipoproteins were studied in 8 Yorkshire swine fed a high fat, high cholesterol diet with either casein or soy protein. After 5 weeks of feeding, the casein group exhibited moderately elevated levels of serum cholesterol (334 +/- 46 mg/dl). The soy protein group showed significantly less hypercholesterolemia as compared to the casein group (122 +/- 8 mg/dl). Swine were subjected to cannulation of mesenteric lymph duct under halothane anesthesia. A single dose of 250 microCi [14C]cholesterol and 10 mCi [3H]leucine was infused into the upper jejunum 2 h after one-fifth of daily food was given. The 3-h lymphatic transport of cholesterol in casein-fed swine was significantly higher than in those fed soy protein. Triglyceride transport values were similar in the 2 groups. The [3H]leucine incorporation study revealed that transport of apo B-48 bore a significant positive relationship to transport of cholesterol in both chylomicron and VLDL fractions of mesenteric lymph. A greater apo B-48 secretion with higher specific activity was probably responsible for the greater transport of cholesterol in chylomicrons in casein-fed than in soy protein-fed swine. Similarly, the transport of lymph VLDL cholesterol in swine fed casein or soy protein paralleled the amount of accompanying apo B-48. Dietary proteins probably influence the intestinal synthesis of apo B-48 which in turn affects cholesterol transport into the lymphatics.
authors.affiliation: Department of Pathology, Neil Hellman Medical Research Building, Albany Medical College, NY 12208.
authors.forename: H T
authors.initials: HT
authors.lastname: Ho
authors.forename: D N
authors.initials: DN
authors.lastname: Kim
authors.forename: K T
authors.initials: KT
authors.lastname: Lee
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D053283:Apolipoprotein B-48; D001055:Apolipoproteins B / Q000096:biosynthesis*; D001692:Biological Transport; D002364:Caseins / Q000494:pharmacology; D002791:Cholesterol, Dietary / Q000008:administration & dosage; D015243:Cholesterol, VLDL / Q000378:metabolism*; D004041:Dietary Fats / Q000008:administration & dosage*; D004044:Dietary Proteins / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D006937:Hypercholesterolemia / Q000378:metabolism; D007408:Intestinal Absorption; D008208:Lymphatic System / Q000378:metabolism*; D008297:Male; D014674:Plant Proteins, Dietary / Q000494:pharmacology; D030262:Soybean Proteins; D013025:Glycine max; D013552:Swine
chemical_list: D000596:Amino Acids; D053283:Apolipoprotein B-48; D001055:Apolipoproteins B; D002364:Caseins; D002791:Cholesterol, Dietary; D015243:Cholesterol, VLDL; D004041:Dietary Fats; D004044:Dietary Proteins; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins