QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Emmert, J. L. Articles by Baker, D. H. Search for Related Content PubMed PubMed Citation Articles by Emmert, J. L. Articles by Baker, D. H.

Hepatic Betaine-Homocysteine Methyltransferase Activity in the Chicken Is Influenced by Dietary Intake of Sulfur Amino Acids, Choline and Betaine^1,2,

Departments of Animal Sciences ^* Food Science and Human Nutrition and Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801

There is much interest in the metabolism of homocysteine, because elevated plasma homocysteine [hyperhomocyst(e)inemia] is an independent risk factor for the development of cardiovascular disease. Four chick assays were conducted to determine the effects of varying dietary sulfur amino acids, choline and betaine on the activity of hepatic betaine-homocysteine methyltransferase (BHMT), an enzyme likely to be important in modulating plasma homocysteine. In Experiment 1, chicks were fed a purified crystalline amino acid diet containing adequate sulfur amino acids and choline. Excess dietary methionine, or the combination of excess cystine with choline or betaine, caused a small increase (P < 0.05) in BHMT activity. In Experiment 2, use of a methionine-deficient purified diet resulted in a threefold increase (P < 0.05) in BHMT activity, and addition of choline or betaine further increased (P < 0.05) BHMT activity. In Experiment 3, use of a methionine-deficient corn-peanut meal diet increased BHMT (P < 0.05) relative to that of chicks supplemented with adequate methionine, and addition of surfeit choline to the methionine-deficient basal diet caused a further increase (P < 0.05). In Experiment 4, addition of both surfeit choline and surfeit betaine to the methionine-deficient corn-peanut meal diet caused an increase (P < 0.05) in BHMT activity relative to that observed in chicks fed the methionine-deficient basal diet. These assays show that large increases in BHMT activity can be produced under methionine-deficient conditions, especially in the presence of excess choline or betaine.

KEY WORDS: • betaine-homocysteine methyltransferase • methionine • choline • betaine • chicks

¹ Presented in part at the Annual Meeting of the Poultry Science Association, August 1995, Edmonton, Alberta, Canada [Emmert, J. L., Garrow, T. A. & Baker, D. H. (1995) Betaine-homocysteine methyltransferase: effects of varying levels of dietary cystine, methionine, choline, and betaine in chicks. Poult. Sci. 74 (suppl. 1): 104].

² The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 USC section 1734 solely to indicate this fact.

³ To whom correspondence should be addressed at: 290 ASL, 1207 West Gregory Drive, Urbana, IL 61801.

Manuscript received 13 February 1996. Revision accepted 1 May 1996.

This article has been cited by other articles:

				R. N. Dilger, T. A. Garrow, and D. H. Baker Betaine Can Partially Spare Choline in Chicks but Only When Added to Diets Containing a Minimal Level of Choline J. Nutr., October 1, 2007; 137(10): 2224 - 2228. [Abstract] [Full Text] [PDF]

				P. B. Pillai, A. C. Fanatico, M. E. Blair, and J. L. Emmert Homocysteine remethylation in broilers fed surfeit choline or betaine and varying levels and sources of methionine from eight to twenty-two days of age. Poult. Sci., October 1, 2006; 85(10): 1729 - 1736. [Abstract] [Full Text] [PDF]

				C. A. Loest, E. C. Titgemeyer, G. S.-J. D. C. Van Metre, and J. S. Smith Methionine as a methyl group donor in growing cattle J Anim Sci, August 1, 2002; 80(8): 2197 - 2206. [Abstract] [Full Text] [PDF]