title: Low and high dietary protein:carbohydrate ratios during pregnancy affect materno-fetal glucose metabolism in pigs.
abstract: Inadequate dietary protein during pregnancy causes intrauterine growth retardation. Whether this is related to altered maternal and fetal glucose metabolism was examined in pregnant sows comparing a high-protein:low-carbohydrate diet (HP-LC; 30% protein, 39% carbohydrates) with a moderately low-protein:high-carbohydrate diet (LP-HC; 6.5% protein, 68% carbohydrates) and the isoenergetic standard diet (ST; 12.1% protein, 60% carbohydrates). During late pregnancy, maternal and umbilical glucose metabolism and fetal hepatic mRNA expression of gluconeogenic enzymes were examined. During an i.v. glucose tolerance test (IVGTT), the LP-HC-fed sows had lower insulin concentrations and area under the curve (AUC), and higher glucose:insulin ratios than the ST- and the HP-LC-fed sows (P < 0.05). Insulin sensitivity and glucose clearance were higher in the LP-HC sows compared with ST sows (P < 0.05). Glucagon concentrations during postabsorptive conditions and IVGTT, and glucose AUC during IVGTT, were higher in the HP-LC group compared with the other groups (P < 0.001). (13)C glucose oxidation was lower in the HP-LC sows than in the ST and LP-HC sows (P < 0.05). The HP-LC fetuses were lighter and had a higher brain:liver ratio than the ST group (P < 0.05). The umbilical arterial inositol concentration was greater in the HP-LC group (P < 0.05) and overall small fetuses (230-572 g) had higher values than medium and heavy fetuses (≥573 g) (P < 0.05). Placental lactate release was lower in the LP-HC group than in the ST group (P < 0.05). Fetal glucose extraction tended to be lower in the LP-HC group than in the ST group (P = 0.07). In the HP-LC and LP-HC fetuses, hepatic mRNA expression of cytosolic phosphoenolpyruvate carboxykinase (PCK1) and glucose-6-phosphatase (G6PC) was higher than in the ST fetuses (P < 0.05). In conclusion, the HP-LC and LP-HC sows adapted by reducing glucose turnover and oxidation and having higher glucose utilization, respectively. The HP-LC and LP-HC fetuses adapted via prematurely expressed hepatic gluconeogenic enzymes.
authors.affiliation: Institute of Nutritional Physiology.
authors.forename: Cornelia C
authors.initials: CC
authors.lastname: Metges
authors.forename: Solvig
authors.initials: S
authors.lastname: Görs
authors.forename: Iris S
authors.initials: IS
authors.lastname: Lang
authors.forename: Harald M
authors.initials: HM
authors.lastname: Hammon
authors.forename: Klaus-Peter
authors.initials: KP
authors.lastname: Brüssow
authors.forename: Joachim M
authors.initials: JM
authors.lastname: Weitzel
authors.forename: Gerd
authors.initials: G
authors.lastname: Nürnberg
authors.forename: Charlotte
authors.initials: C
authors.lastname: Rehfeldt
authors.forename: Winfried
authors.initials: W
authors.lastname: Otten
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D019540:Area Under Curve; D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D004032:Diet; D050528:Diet, Carbohydrate-Restricted; D018753:Diet, Protein-Restricted; D004040:Dietary Carbohydrates / Q000008:administration & dosage* / Q000494:pharmacology; D004044:Dietary Proteins / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D047109:Fetal Development; D005317:Fetal Growth Retardation / Q000209:etiology*; D005333:Fetus / Q000378:metabolism; D005934:Glucagon / Q000097:blood; D005943:Gluconeogenesis; D005947:Glucose / Q000378:metabolism*; D005951:Glucose Tolerance Test; D007294:Inositol / Q000097:blood; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D019344:Lactic Acid / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D011248:Pregnancy Complications; D039401:Prenatal Nutritional Physiological Phenomena; D011488:Protein Deficiency / Q000150:complications*; D013552:Swine; D014472:Umbilicus
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D007328:Insulin; D019344:Lactic Acid; D007294:Inositol; D005934:Glucagon; D005947:Glucose