title: Intermediate metabolism in association with the amino acid profile during the third trimester of normal pregnancy and diet-controlled gestational diabetes.
abstract: OBJECTIVE
  The aim of this study was to investigate the levels of fasting maternal plasma amino acids in normal pregnant women and compare them with those in gestational diabetes controlled by diet only. We also wished to delineate the alterations occurring in intermediate metabolic pathways in gestational diabetes.
  
  
  METHODS
  Forty-six (64.7%) pregnant women with uncomplicated pregnancy (NP group) and 25 (35.2%) women with gestational diabetes mellitus (GDM group) at 30-33 weeks of gestation participated in the study. Fasting maternal plasma carnitine (total, free, and acyl-carnitine), beta-hydroxybutyrate, free fatty acids, glycosylated hemoglobin, and 21 amino acids were assayed.
  
  
  RESULTS
  Fasting carnitine esters exhibited lower levels in the GDM group (P = .03). Higher levels of fasting beta-hydroxybutyrate and free fatty acids (P < .001 and .02, respectively) were observed in the GDM group. Of the 21 amino acids, only methionine, glycine, alanine, citrulline, and ornithine levels were found at significantly higher levels in the NP group (P = .03, P < .001, P = .01, P < .001, and P < .001, respectively).
  
  
  CONCLUSIONS
  In gestational diabetes, ketogenic amino acids and the branched-chain amino acid isoleucine are released at low rates from skeletal muscle and are mostly catabolized in the liver rather than in peripheral tissues. In contrast, in normal pregnancy proteinolysis is enhanced, and the ketogenic amino acids along with branched-chain amino acids are catabolized in both the liver and peripheral tissues. As a result, ketogenic amino acids are fully oxidized and gluconeogenesis becomes more efficient, whereas urea cycle operates at a higher rate.
authors.affiliation: First Department of Obstetrics and Gynecology, University of Athens School of Medicine, Alexandra University Hospital, Athens, Greece. kpappa@imbb.forth.gr
authors.forename: Kalliopi I
authors.initials: KI
authors.lastname: Pappa
authors.forename: George
authors.initials: G
authors.lastname: Vlachos
authors.forename: Marianna
authors.initials: M
authors.lastname: Theodora
authors.forename: Maria
authors.initials: M
authors.lastname: Roubelaki
authors.forename: Konstantina
authors.initials: K
authors.lastname: Angelidou
authors.forename: Aris
authors.initials: A
authors.lastname: Antsaklis
mesh_terms: D000328:Adult; D000596:Amino Acids / Q000097:blood* / Q000378:metabolism; D016640:Diabetes, Gestational / Q000178:diet therapy* / Q000378:metabolism*; D005215:Fasting; D005260:Female; D006801:Humans; D011247:Pregnancy; D011263:Pregnancy Trimester, Third / Q000378:metabolism*
chemical_list: D000596:Amino Acids