Effect of Dietary Sucrose and Cholesterol on Atherosclerosis, Liver Malate Dehydrogenase and Plasma Lipoprotein Lipase Levels in Pigeons

Abstract

Eight-week old atherosclerosis-resistant Show Racer (SR) and -susceptible White Carneau (WC) pigeons were fed one of four puri fied diets as follows: a basal (dextrin) diet (B), a basal-cholesterol diet ( BC ), a sucrose diet ( S), or a sucrose-cholesterol diet ( SC ). Blood choles terol and triglycA©ride concentrations, liver malate dehydrogenase activity (MDHA), liver cholesterol and triglycA©rideconcentrations, liver protein and total lipid levels, and plasma lipoprotein lipase activity (LPLA) were assayed and evaluated statistically to determine their relationships to dietary modification and their significance in the pathogenesis of aortic athero sclerosis. Cholesterol supplementation increased the prevalence of fatty streaking in the aortas of the WC over those of the SR, and it also increased the severity of fatty streaking in both the WC (with one exception) and SR pigeons compared to their counterparts fed diets without cholesterol. Sucrose feeding did not consistently alter the levels of blood cholesterol and triglycA©rides. The MDHA of all the SR, when expressed on the basis of g of liver protein were significantly higher than those of the WC fed the same diet except those fed the basal diet. No significant differences were found in LPLA between the two breeds fed the various diets. All tissue lipid levels were positively correlated while the liver MDHA negatively correlated with the severity of the disease. For the SR, MDHA was also negatively correlated with the prevalence of fatty streaking. A larger num ber of SR developed the disease when subjected to elevated blood triglyc A©ride levels while a larger number of WC developed the disease when subjected to elevated blood cholesterol levels. J. Nutr. 108: 944-953, 1978.