The lipid metabolism in normal and diabetic pregnancy

In order to study the lipid metabolism in normal and diabetic pregnancy, the serum obtained in the third trimester and postpartum was fractionated into VLDL, LDL, and HDL by ultracentrifugation. The lipid concentrations in each lipoprotein fraction were determined. The hyperlipidemia induced by pregnancy was mainly due to the increase in the amount of VLDL-triglyceride, which was enhanced in diabetic pregnancy. Each lipid in the VLDL fraction was increased, but compositionally unchanged from that observed in non-pregnant women. On the contrary, the percentage of triglyceride in the LDL and HDL increased with reciprocal percentage reductions in cholesterol and phospholipid. This tendency was more prominent in diabetic pregnancy than in normal pregnancy. PHLA, which was determined to study the catabolism of triglyceride, was suppressed in the third trimester in normal and diabetic pregnancy, compared to that in non-pregnant women. Moreover, the ratio of apo C II/C III1 + C III2 in the VLDL was investigated and found to be significantly lower in the third trimester in normal and diabetic pregnancy than than in non-pregnant women. The impaired removal of VLDL-triglyceride was one of the factors which caused hyperlipidemia during pregnancy. In addition, the overproduction of VLDL-triglyceride affected hyperlipidemia in diabetic pregnancy.