HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map 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 Raguso, C. A Articles by Young, V. R Search for Related Content PubMed PubMed Citation Articles by Raguso, C. A Articles by Young, V. R Agricola Articles by Raguso, C. A Articles by Young, V. R

Cysteine kinetics and oxidation at different intakes of methionine and cystine in young adults^1,2,3

¹ From the Laboratory of Human Nutrition, School of Science and Clinical Research Center, Massachusetts Institute of Technology, Cambridge, MA, and Shriners Burns Hospital, Boston.

Background: We previously studied methionine kinetics and oxidation with the tracer L-[1-¹³C, methyl-²H₃]methionine.

Objectives: We sought to explore methionine-cysteine interrelations in adults by using L-[1-¹³C]cysteine under different dietary conditions.

Design: In experiment 1, 12 adults consumed a protein-free diet for 6 d. On day 7, methionine (n = 6) or cysteine (n = 6) oxidation rates were measured during an 8-h continuous infusion of L-[1-¹³C, methyl-²H₃]methionine or L-[1-¹³C]cysteine, respectively. In experiment 2, 6 young men consumed 3 diets for 6 d each before a tracer study on day 7 with L-[1-¹³C]cysteine. The amounts (in mg•kg^-1•d^-1) of methionine and cysteine, respectively, were: high-methionine (HM) diet, 13 and 0; low-methionine (LM) diet, 6.5 and 0; and methionine-plus-cystine (MC) diet, 6.5 and 5.6. Cysteine flux and oxidation rates were determined and sulfur amino acid (SAA, methionine plus cysteine) balances were estimated.

Results: In experiment 1, rates of methionine and cysteine oxidation were similar to losses predicted from obligatory nitrogen losses. In experiment 2, SAA balance was less negative when subjects consumed the HM diet than the LM and MC diets (interaction, P = 0.034), largely because of a difference in fed-state balance (HM compared with LM, P < 0.01; HM compared with MC, P < 0.05). There was no evidence of a sparing effect of dietary cystine on the methionine requirement.

Conclusion: These studies support use of [1-¹³C]cysteine for studying whole-body SAA oxidation and conclusions that maintenance of SAA balance is best achieved by supplying methionine at approximately the FAO/WHO/UNU recommendations for total SAA intake (13 mg•kg^-1•d^-1).

Key Words: Cysteine oxidation • cysteine kinetics • sulfur amino acid metabolism • obligatory oxidative losses • obligatory nitrogen losses • young adults • methionine • cystine

This article has been cited by other articles:

				D. P. Jones Radical-free biology of oxidative stress Am J Physiol Cell Physiol, October 1, 2008; 295(4): C849 - C868. [Abstract] [Full Text] [PDF]

				R. A Blanco, T. R Ziegler, B. A Carlson, P.-Y. Cheng, Y. Park, G. A Cotsonis, C. J. Accardi, and D. P Jones Diurnal variation in glutathione and cysteine redox states in human plasma Am. J. Clinical Nutrition, October 1, 2007; 86(4): 1016 - 1023. [Abstract] [Full Text] [PDF]

				M. A Humayun, J. M Turner, R. Elango, M. Rafii, V. Langos, R. O Ball, and P. B Pencharz Minimum methionine requirement and cysteine sparing of methionine in healthy school-age children. Am. J. Clinical Nutrition, November 1, 2006; 84(5): 1080 - 1085. [Abstract] [Full Text] [PDF]

				M. Reid, A. Badaloo, T. Forrester, and F. Jahoor In vivo rates of erythrocyte glutathione synthesis in adults with sickle cell disease Am J Physiol Endocrinol Metab, July 1, 2006; 291(1): E73 - E79. [Abstract] [Full Text] [PDF]

				N. K. Fukagawa Sparing of Methionine Requirements: Evaluation of Human Data Takes Sulfur Amino Acids Beyond Protein J. Nutr., June 1, 2006; 136(6): 1676S - 1681S. [Abstract] [Full Text] [PDF]

				S. Mercier, D. Breuille, C. Buffiere, J. Gimonet, I. Papet, P. P. Mirand, and C. Obled Methionine kinetics are altered in the elderly both in the basal state and after vaccination Am. J. Clinical Nutrition, February 1, 2006; 83(2): 291 - 298. [Abstract] [Full Text] [PDF]

				A. V Kurpad, M. M Regan, S. Varalakshmi, J. Gnanou, A. Lingappa, and V. R Young Effect of cystine on the methionine requirement of healthy Indian men determined by using the 24-h indicator amino acid balance approach Am. J. Clinical Nutrition, December 1, 2004; 80(6): 1526 - 1535. [Abstract] [Full Text] [PDF]

				W. Kriengsinyos, L. J. Wykes, L. A. Goonewardene, R. O. Ball, and P. B. Pencharz Phase of menstrual cycle affects lysine requirement in healthy women Am J Physiol Endocrinol Metab, September 1, 2004; 287(3): E489 - E496. [Abstract] [Full Text] [PDF]

				B. Rakotoambinina, L. Marks, A. M. Badran, F. Igliki, F. Thuillier, P. Crenn, B. Messing, and D. Darmaun Taurine kinetics assessed using [1,2-13C2]taurine in healthy adult humans Am J Physiol Endocrinol Metab, August 1, 2004; 287(2): E255 - E262. [Abstract] [Full Text] [PDF]

				P. B. Soeters, M. C. G. van de Poll, W. G. van Gemert, and C. H. C. Dejong Amino Acid Adequacy in Pathophysiological States J. Nutr., June 1, 2004; 134(6): 1575S - 1582S. [Abstract] [Full Text] [PDF]

				A. K. Shoveller, J. A. Brunton, J. D. House, P. B. Pencharz, and R. O. Ball Dietary Cysteine Reduces the Methionine Requirement by an Equal Proportion in Both Parenterally and Enterally Fed Piglets J. Nutr., December 1, 2003; 133(12): 4215 - 4224. [Abstract] [Full Text] [PDF]

				A. V Kurpad, M. M Regan, S. Varalakshmi, J. Vasudevan, J. Gnanou, T. Raj, and V. R Young Daily methionine requirements of healthy Indian men, measured by a 24-h indicator amino acid oxidation and balance technique Am. J. Clinical Nutrition, May 1, 2003; 77(5): 1198 - 1205. [Abstract] [Full Text] [PDF]

				M. Di Buono, L. J. Wykes, D. E. C. Cole, R. O. Ball, and P. B. Pencharz Regulation of Sulfur Amino Acid Metabolism in Men in Response to Changes in Sulfur Amino Acid Intakes J. Nutr., March 1, 2003; 133(3): 733 - 739. [Abstract] [Full Text] [PDF]

				V. R Young Got some amino acids to spare? Am. J. Clinical Nutrition, December 1, 2001; 74(6): 709 - 711. [Full Text]

				M. Di Buono, L. J Wykes, R. O Ball, and P. B Pencharz Dietary cysteine reduces the methionine requirement in men Am. J. Clinical Nutrition, December 1, 2001; 74(6): 761 - 766. [Abstract] [Full Text]

				M. J. MacCoss, N. K. Fukagawa, and D. E. Matthews Measurement of intracellular sulfur amino acid metabolism in humans Am J Physiol Endocrinol Metab, June 1, 2001; 280(6): E947 - E955. [Abstract] [Full Text] [PDF]

				F. Mariotti, M. E Pueyo, D. Tomé, S. Bérot, R. Benamouzig, and S. Mahé The Influence of the Albumin Fraction on the Bioavailability and Postprandial Utilization of Pea Protein Given Selectively to Humans J. Nutr., June 1, 2001; 131(6): 1706 - 1713. [Abstract] [Full Text]

				D. W. Jacobsen Hyperhomocysteinemia and Oxidative Stress : Time for a Reality Check? Arterioscler. Thromb. Vasc. Biol., May 1, 2000; 20(5): 1182 - 1184. [Full Text] [PDF]

				J. Lyons, A. Rauh-Pfeiffer, Y. M. Yu, X.-M. Lu, D. Zurakowski, R. G. Tompkins, A. M. Ajami, V. R. Young, and L. Castillo Blood glutathione synthesis rates in healthy adults receiving a sulfur amino acid-free diet PNAS, May 9, 2000; 97(10): 5071 - 5076. [Abstract] [Full Text] [PDF]