Choline supplementation increases tissue concentrations of carnitine and lowers body fat in guinea pigs

James W. Daily, Nobuko Hongu, Randall L. Mynatt, Dileep S. Sachan

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

It has been documented that choline supplementation results in urinary conservation of carnitine in both humans and guinea pigs. This conservation in guinea pigs is associated with increased concentrations of carnitine in skeletal muscle for which no functional consequences have been reported. The objective of this study was to evaluate changes in fat metabolism and body composition as a consequence of the increased tissue carnitine in choline-supplemented guinea pigs. Guinea pigs were given free access to commercial diet without or with 3 g choline/kg diet. Using indirect calorimetry, the respiratory exchange ratios (RER) of the animals were determined under normal, exercise, and unfed conditions. There were no differences in RER between supplemented and nonsupplemented groups under any of the conditions. The RER data lead to the conclusion that choline-carnitine did not promote oxidation of fat over carbohydrates for energy. However, proximate analysis of carcass revealed significantly lower total body fat and higher body proteins in the choline-supplemented animals compared with the nonsupplemented animals. These apparently contradictory results are explained by the hypothesis that the acetates generated by the β-oxidation of fatty acids are transferred to carnitine and not oxidized to carbon dioxide, resulting in little or no shift in RER. Copyright (C) 1998 Elsevier Science Inc.

Original languageEnglish (US)
Pages (from-to)464-470
Number of pages7
JournalJournal of Nutritional Biochemistry
Volume9
Issue number8
DOIs
StatePublished - Aug 1998
Externally publishedYes

Fingerprint

Carnitine
Choline
Adipose Tissue
Guinea Pigs
Fats
Tissue
Animals
Nutrition
Conservation
Diet
Oxidation
Indirect Calorimetry
Calorimetry
Body Composition
Metabolism
Carbon Dioxide
Muscle
Skeletal Muscle
Acetates
Fatty Acids

Keywords

  • Body fat
  • Choline-carnitine
  • Energy fuels
  • Guinea pigs
  • RER

ASJC Scopus subject areas

  • Biochemistry
  • Endocrinology, Diabetes and Metabolism

Cite this

Choline supplementation increases tissue concentrations of carnitine and lowers body fat in guinea pigs. / Daily, James W.; Hongu, Nobuko; Mynatt, Randall L.; Sachan, Dileep S.

In: Journal of Nutritional Biochemistry, Vol. 9, No. 8, 08.1998, p. 464-470.

Research output: Contribution to journalArticle

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