A high protein:low carbohydrate (HP‐LC) diet during pregnancy affects glucose metabolism in last trimester sows and fetuses and leads to intrauterine growth restriction (IUGR)

Abstract

An HP‐LC diet is effective to lose weight but its impact during pregnancy is unclear. Since obesity during pregnancy is an issue in programming of metabolic disorders in offspring we first investigated effects of HP‐LC diet in a porcine pregnancy model. Throughout pregnancy primiparous sows were fed an HP‐LC diet with 30% protein or an adequate control (C) diet (12% protein) made isoenergetic by protein exchange (n=9/group). We performed an i.v. glucose (G) tolerance test (IVGTT) at 89 days post conception (dpc), measured G, insulin (INS) and glucagon (GLG) levels, and also INS sensitivity by RQUICKI. At 94 dpc we analyzed umbilical vein plasma G, fructose (FRC) and inositol (ISL) concentrations as well as fetal hepatic mRNA levels of cytosolic phosphoenolpyruvate carboxykinase (PEPCKc) and glucose 6 phosphatase (G6P). During IVGTT plasma G AUC and GLG of HP‐LC sows were higher while INS sensitivity was lower (P<0.05). HP‐LC fetuses were lighter but brain to liver ratio was higher than in C (P<0.05). Umbilical plasma G and FRC did not differ among groups but ISL tended to be higher in HP‐LC (P<0.1). Hepatic PEPCKc mRNA was higher in HP‐LC than in C fetuses (P<0.05), whereas G6Pase expression did not differ. In conclusion, in the HP‐LC group in spite of low maternal G intake, G supply to the fetuses seemed to be favored whereas ISL signaled IUGR, and PEPCKc indicated premature maturation of fetal gluconeogenesis.Supported by DFG