title: Low availability of carnitine precursors as a possible reason for the diminished plasma carnitine concentrations in pregnant women.
abstract: BACKGROUND
  It has been shown that plasma carnitine concentrations decrease markedly during gestation. A recent study performed with a low number of subjects suggested that this effect could be due to a low iron status which leads to an impairment of carnitine synthesis. The present study aimed to confirm this finding in a greater number of subjects. It was moreover intended to find out whether low carnitine concentrations during pregnancy could be due to a reduced availability of precursors of carnitine synthesis, namely trimethyllysine (TML) and gamma-butyrobetaine (BB).
  
  
  METHODS
  Blood samples of 79 healthy pregnant women collected at delivery were used for this study.
  
  
  RESULTS
  There was only a weak, non-significant (P > 0.05), correlation between plasma concentration of ferritin and those of free and total carnitine. There was no correlation between other parameters of iron status (plasma iron concentration, hemoglobin, MCV, MCH) and plasma concentration of free and total carnitine. There were, however, significant (P < 0.05) positive correlations between concentrations of TML and BB and those of free and total carnitine in plasma.
  
  
  CONCLUSIONS
  The results of this study suggest that an insufficient iron status is not the reason for low plasma carnitine concentrations observed in pregnant women. It is rather indicated that low plasma carnitine concentrations are caused by a low availability of precursors for carnitine synthesis during gestation.
authors.affiliation: Institute of Animal Nutrition and Nutrition Physiology, Justus-Liebig-University, Giessen, Germany.
authors.forename: Robert
authors.initials: R
authors.lastname: Ringseis
authors.forename: Nicole
authors.initials: N
authors.lastname: Hanisch
authors.forename: Gregor
authors.initials: G
authors.lastname: Seliger
authors.forename: Klaus
authors.initials: K
authors.lastname: Eder
mesh_terms: D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000097:blood; D001622:Betaine / Q000031:analogs & derivatives* / Q000378:metabolism; D002331:Carnitine / Q000172:deficiency / Q000378:metabolism* / Q000502:physiology; D004909:Erythrocyte Indices / Q000502:physiology; D005260:Female; D005293:Ferritins / Q000097:blood; D005858:Germany; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D016014:Linear Models; D008239:Lysine / Q000031:analogs & derivatives* / Q000378:metabolism; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000097:blood; D011263:Pregnancy Trimester, Third / Q000502:physiology
chemical_list: D006454:Hemoglobins; D001622:Betaine; C003712:trimethyllysine; C002889:gamma-butyrobetaine; D005293:Ferritins; D008239:Lysine; D002331:Carnitine