Effects of dietary supplemented amino acids on endogenous hypercholesterolemia in rats.
Effects of additions of amino acids to a 20% casein diet on serum cholesterol (Ch) were studied in hypothyroid and hepatoma-bearing rats with endogenous hypercholesterolemia as well as in normal rats. In normal Wistar rats, methionine (Met) was hypercholesterolemic at the "nutritional" level (0.2-0.4%), but hypocholesterolemic at the "excess" level (1.2-2.4%). In Wistar rats with hypothyroidism induced by thiouracil, the addition of excess (1.2%) Met to the 20% casein diet reduced an endogenous hypercholesterolemia due to hypothyroidism by suppressing an elevation in (VLDL + LDL)-Ch with no significant influence on HDL-Ch. In Donryu rats received a subcutaneous implantation of AH109A cells (an ascites hepatoma line), either 1.2% Met, 1.2% cystine (Cys), or 1.2% Met and 2.5% glycine (Gly) in combination improved a hepatoma-induced hypercholesterolemia and abnormal serum lipoprotein profiles by suppressing a hepatoma-induced increase in (VLDL + LDL)-Ch. From Ch turnover studies in hepatoma-bearing rats, an impaired catabolism of Ch in the liver was suggested to be one cause for the hepatoma-induced elevation in (VLDL + LDL)-Ch. One of the dietary manipulations. met and Gly in combination (Met + Gly), was found to improve the impaired Ch catabolism, this leading to a reduction of the (VLDL + LDL)-Ch level by Met + Gly in hepatoma-bearing rats.
Yagasaki
K
K
Department of Agricultural Chemistry, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Japan.
Funabiki
R
R
D000596:Amino Acids / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D002364:Caseins / Q000008:administration & dosage / Q000494:pharmacology; D003553:Cystine / Q000008:administration & dosage / Q000494:pharmacology; D004044:Dietary Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D005998:Glycine / Q000008:administration & dosage / Q000494:pharmacology; D006937:Hypercholesterolemia / Q000097:blood* / Q000209:etiology; D007037:Hypothyroidism / Q000097:blood / Q000139:chemically induced / Q000150:complications; D008114:Liver Neoplasms, Experimental / Q000150:complications; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013889:Thiouracil
D000596:Amino Acids; D002364:Caseins; D004044:Dietary Proteins; D003553:Cystine; D013889:Thiouracil; D008715:Methionine; D005998:Glycine