Increased serum and liver lipid mass and hepatic 3-hydroxy-3-methylglutaryl CoA reductase activities in rabbits fed soy protein saturated fat diets.
Male New Zealand white rabbits were pair-fed high fat, soy protein-dextrose diets containing either hydrogenated coconut oil (HC) or safflower oil (SA) for 155 days. A third group was fed a low fat, soy protein-dextrose-corn oil diet (SD) previously shown to be normocholesterolemic in the rabbit. All animals gained similar amounts of weight during the feeding period. The HC group became significantly hypercholesterolemic after 28 days with peak elevations at 58 days. Although some adaptation in the response occurred thereafter, serum cholesterol concentrations remained significantly elevated. Serum triglyceride concentrations were similarly elevated in this group. Rabbits fed either the SD or SA diets remained normocholesterolemic. At the end of the feeding period significant elevations of serum total phospholipid and phosphatidyl inositol concentrations were seen in the HC group. Elevations of all other phospholipid classes were also observed but were not statistically significant. Lipid analysis of HC livers revealed significant elevations of free and esterified cholesterol and hepatic microsomal HMG-CoA reductase activities. Increased serum and hepatic cholesterol and sterol biosynthesis in rabbits can thus be induced solely as a result of dietary coconut oil. The elevation of certain serum phospholipids may reflect tissue changes and is consistent with either increased biosynthesis or the impairment of phospholipase activities. Whether dietary fatty acids can affect cell signaling through inhibition of phospholipid turnover remains to be elucidated.
Bauer
J E
JE
J. Hillis Miller Health Sciences Center, Department of Physiological Sciences, University of Florida, Gainesville 32610.
D000818:Animals; D001835:Body Weight; D002784:Cholesterol / Q000032:analysis / Q000097:blood; D004041:Dietary Fats / Q000008:administration & dosage*; D004044:Dietary Proteins / Q000008:administration & dosage*; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism*; D008055:Lipids / Q000032:analysis* / Q000097:blood; D008099:Liver / Q000032:analysis* / Q000033:anatomy & histology / Q000201:enzymology; D008297:Male; D009929:Organ Size; D010743:Phospholipids / Q000032:analysis / Q000097:blood; D011817:Rabbits; D013025:Glycine max; D014280:Triglycerides / Q000032:analysis / Q000097:blood
D004041:Dietary Fats; D004044:Dietary Proteins; D008055:Lipids; D010743:Phospholipids; D014280:Triglycerides; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases