Impact of a cholesterol enriched diet on maternal and fetal plasma lipids and fetal deposition in pregnant rabbits

Pregnancy is associated with a hypercholesterolemic and a hyperlipidemic st ate. The totality of the essential fatty acids and 50% of the lipids needed by the fetus are transferred by the placenta from the maternal circulation . The hypothesis of this study is that an augmentation of the maternal plas matic cholesterol is modifying the fetal lipids accumulation and developmen t during rabbit pregnancy. To demonstrate the impact of a cholesterol enric hed diet on plasma lipids during rabbit's pregnancy and on their fetus, we have established two groups: control and hypercholesterolemic rabbits (fed with a 0,2% cholesterol diet). Blood samples were collected before mating a nd at each trimester of pregnancy for analysis of lipid fractions and their lipoproteins. Plasma analysis shows that starting the 10(th) day of pregna ncy the concentration of total-cholesterol and lipoproteins decreases for b oth groups. We have demonstrated that for the hypercholesterolemic group, c oncentrations of total-cholesterol (631%) and lipoproteins are significantl y higher at the end of pregnancy than those for the control group. For both groups, after 20 days of pregnancy, triglycerides metabolism was biphasic showing a significant increase followed by a diminution in their concentrat ion. In both groups, free fatty acids increases significantly at the end of the pregnancy (537.5% for the control group and 462.5% for the hypercholes terolemic group). Furthermore, the offsprings of hypercholesterolemic dams manifest a lower birth weight (15.5%) than those of control group. Our resu lts demonstrate that a cholesterol enriched diet modifies greatly the fetal development and lipid metabolism during rabbit's pregnancy. These modifica tions could be useful for the understanding of the interaction between diet and fetal development in rabbit and probably during human pregnancy.