Dietary Requirements for Indispensable Amino Acids in Adult Humans: New Concepts, Methods of Estimation, Uncertainties and Challenges

Metges, C. C.; Petzke, K. J.; Young, Vernon R.

doi:10.1159/000012794

Cited by 8 publications

(4 citation statements)

References 32 publications

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“…Concerning the N balance, it is known that increased energy intake at a constant N intake increases the N balance [11] and that carbohydrates or fat modulate splanchnic retention and peripheral availability of dietary N [12] . However, branched-chain AA are especially potent modulators of the protein turnover [13] .…”

Section: Discussionmentioning

confidence: 99%

Effects of Various Dietary Amino Acid Preparations for Phenylketonuric Patients on the Metabolic Profiles along with Postprandial Insulin and Ghrelin Responses

et al. 2007

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Aim: We investigated the metabolic profiles along with insulin and ghrelin responses following ingestion of various amino acid (AA) substitutes commonly used in the treatment of phenylketonuria to study the effects of added macronutrients. Methods: Twenty healthy and 6 phenylketonuric adults ingested AA mixtures with or without carbohydrates and fat (Anamix, Easiphen, or p-am 3; 0.35 g AA/kg body weight); milk powder shakes were used for control purposes. Serum AA, glucose, urea, insulin, and ghrelin were measured over 5 h. Results: Peak AA concentrations were achieved at around 60 min postprandially for supplemented AA powders and control shakes, significantly later than for pure AA. Of interest, the mean Phe/Tyr ratio declined by 40–50% in phenylketonuric patients following intake of Easiphen, Anamix, or p-am 3. The insulin peaks, up to 500% as compared with baseline, occurred at 30 min and were approximately 100% higher after intake of AA plus macronutrients. Glucose and urea remained constant. Ghrelin showed a nadir at 60 min, followed by a rise leading to a 30% increase of initial concentrations for pure AA as compared with more constant levels for preparations with macronutrients. Conclusion: An oral AA bolus together with macronutrients retards hyperaminoacidemia, displays a higher insulin secretion, normoglycemia, and more stable ghrelin concentrations, whereas the pure AA tested here exerted weaker anabolic effects.

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Section: Discussionmentioning

confidence: 99%

Effects of Various Dietary Amino Acid Preparations for Phenylketonuric Patients on the Metabolic Profiles along with Postprandial Insulin and Ghrelin Responses

et al. 2007

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“…It is difficult to find a reasonable explanation for the high efficiency of utilization of histidine. Histidine is considered essential for most mammalian species ( Fuller and Garthwaite , 1993), including human adults ( Metges et al, 1999) and there seems to be no reason to suspect that it is synthesized de novo in the body. A high marginal efficiency of histidine utilization was also found in our previous experiments with rats ( Heger and Frydrych , 1985).…”

Section: Discussionmentioning

confidence: 99%

Efficiency of amino acid utilization in the growing pig at suboptimal levels of intake: branched‐chain amino acids, histidine and phenylalanine + tyrosine

Heger¹,

Phung²,

Křížová³

et al. 2003

Animal Physiology Nutrition

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Five balance experiments on growing pigs were carried out to study the marginal efficiency of utilization of isoleucine, leucine, valine, histidine and phenylalanine + tyrosine and to estimate their requirements for maintenance. Purified diets based on casein and crystalline amino acids as the sole source of N contained graded levels of each amino acid, corresponding to protein accretion rates of 0, 33, 66, 99 and 132 g/day, respectively. All other essential amino acids were given in a 30% excess. N retention increased linearly (p < 0.01) as the dietary concentration of the limiting amino acid increased. Based on linear regression equations relating amino acid deposition in body protein to amino acid intake, marginal efficiencies of ileal digestible amino acid utilization were calculated to be isoleucine - 0.81, leucine - 0.81, valine - 0.82, histidine - 1.17 and phenylalanine + tyrosine - 0.67. Extrapolating the regression equations to zero N retention, the daily requirements of amino acids for N equilibrium were estimated to be (mg/kg0.75) isoleucine - 18, leucine - 33, valine - 23, histidine - 14 and phenylalanine + tyrosine - 43.

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“…The release of histidine mainly from carnosine and hemoglobin allows experimental animals to maintain nitrogen equilibrium even on histidine-deficient diets (Fuller and Garlick, 1994). Nowadays histidine has been recognized as an essential amino acid for human adults (Metges et al, 1999). One mysterious thing is that in spite of the long-term argument with regard to the essentiality of histidine for human adults, there have been no reports on the activity of histidinol dehydrogenase in animal tissues which had already been revealed in microorganisms (Andorn and Aronovitch, 1982) and plants (Nagai and Scheidegger, 1991), although incorporations of 15 N from 15 NH 4 Cl and 15 N-urea in human adults and 14 C from H 14 COOH into histidine in human fetal liver (Levy and Coon, 1952) were examined.…”

Section: Human Beingsmentioning

confidence: 99%

“…In this regard, we have recently achieved a strong suggestion that especially 'histidine' among ten EAAs for immature rats could be synthesized on a large scale by cattle organs (Wadud et al, 2001b;Wadud et al, 2002), which had been hinted in the course of the experiments on amino acid metabolism by (Wadud et al, 2001a) and on evaluation of nutritive values of rumen microorganisms (Onodera and Koga, 1987). Incidentally, histidine is the only amino acid on which disputes have continued for as long a period as nearly 25 years especially with regard to its essentiality in adult human (Fuller and Garlick, 1994;Metges et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Essentiality of Histidine in Ruminant and Other Animals Including Human Beings

Onodera¹

2003

Asian Australas. J. Anim. Sci

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Concept and establishment of essential amino acids in animals and human beings rendered immeasurable contributions to animal production and human health. In ruminant animals, however, essential amino acids have never been completely established. The present review proposes a hypothesis that histidine may not be an essential amino acid for normal growing cattle (Japanese black) at least at the growing stage after about 450 kg of body weight on the basis of the experimental results of histidinol dehydrogenase activities in some tissues of the cattle together with hints from which the hypothesis was derived. At the same time, histidinol dehydrogenase activities in liver, kidney and muscle of swine, mouse, fowl and wild duck will be shown and the essentiality of histidine in these animals will be discussed. Finally, the essentiality of histidine for adult human will briefly be discussed.

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Dietary Requirements for Indispensable Amino Acids in Adult Humans: New Concepts, Methods of Estimation, Uncertainties and Challenges

Cited by 8 publications

References 32 publications

Effects of Various Dietary Amino Acid Preparations for Phenylketonuric Patients on the Metabolic Profiles along with Postprandial Insulin and Ghrelin Responses

Effects of Various Dietary Amino Acid Preparations for Phenylketonuric Patients on the Metabolic Profiles along with Postprandial Insulin and Ghrelin Responses

Efficiency of amino acid utilization in the growing pig at suboptimal levels of intake: branched‐chain amino acids, histidine and phenylalanine + tyrosine

Essentiality of Histidine in Ruminant and Other Animals Including Human Beings

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