Effect of ketogenic diets in gestation on some characteristics of carbohydrate metabolism in fetal pig brain and liver.

Maternal ketosis was induced in sows by feeding 20% of the dietary energy as 1,3-butylene glycol (BG), medium-chain triglycerides (MCT), or a combination of the two. Brain development and hepatic glycogen synthetase and phosphorylase were assessed in 105-day-old fetuses as a function of maternal diets. Butylene glycol was more ketogenic than MCT. Furthermore, maternal ketosis induced by BG increased fetal brain weight, protein content, and cell size. Maternal ketosis also increased fetal liver glycogen possibly by causing the accumulation of glucose residues in the liver by suppressing liver glycolysis. In addition, glycogen synthetase alpha was increased by maternal ketosis. A fetal form of synthetase was noted in the liver which was stimulated by glucose-6-phosphate (G6P) in the presence of Na2SO4, an inhibitor of the G6P-dependent form of the enzyme.