DIET AND TISSUE GROWTH

The relative toxicity of chloroform given subcutaneously to rats fed on two diets deficient in respect to their nitrogenous components, the sole sources of protein in which were, respectively, gliadin and gelatin and to rats without food, is as follows: gelatin diet > fasting > gliadin diet. The rate of regeneration of liver cells after chloroform poisoning in rats fed a diet in which gliadin is the only protein is about as rapid as that in animals fed a diet containing casein as the source of nitrogen. The rate of regeneration on a food containing its nitrogen as gelatin and also during fasting is definitely slower than that in animals fed the gliadin food. The results of these experiments indicate that the requirement for the essential amino acids for growth of individual organs of the body is less than that for correlated growth of the whole body.

Download Full-text

Penambahan Lisin pada Pakan Komersial terhadap Retensi Protein dan Retensi Energi Ikan Bawal Air Tawar (Colossoma macropomum) [Lysine Addition on Commercial Feed to the Protein Retention and Energy Retention Colossoma macropomum]

Jurnal Ilmiah Perikanan dan Kelautan ◽

10.20473/jipk.v9i2.7637 ◽

2017 ◽

Vol 9 (2) ◽

pp. 98 ◽

Cited By ~ 2

Author(s):

Afifa Khalida ◽

Agustono Agustono ◽

Widya Paramita

Keyword(s):

Amino Acids ◽

Essential Amino Acids ◽

Quality Parameters ◽

The Body ◽

Colossoma Macropomum ◽

Protein Retention ◽

Body Tissues ◽

Commercial Feed ◽

Energy Retention ◽

Range Test

AbstrakAsam amino adalah komponen terkecil yang menyusun protein. Sejumlah asam amino akan dihubungkan satu sama lain melalui perantara ikatan peptida untuk membentuk protein. Asam amino telah dibagi menjadi dua; yaitu asam amino esensial dan asam amino non-esensial. Asam amino esensial adalah asam amino yang tidak dapat disintesis oleh tubuh ikan; karena itu asam amino esensial harus ada dalam pakan. Lisin adalah salah satu dari sepuluh asam amino esensial, fungsi lisin adalah untuk pertumbuhan dan perbaikan jaringan tubuh. Penelitian ini bertujuan untuk mengetahui pengaruh lisin dalam pakan komersial terhadap retensi protein dan retensi energi ikan bawal air tawar. Metode yang digunakan adalah desain eksperimen rancangan acak lengkap. Perlakuan yang digunakan adalah kadar lisin yang berbeda, yaitu P0 (0%), P1 (0,6%), P2 (1,2%), P3 (2,4%), P4 (4,8%) dan perlakuan diulang 4 kali. Parameter utama yang diamati adalah retensi protein dan retensi energi pada air tawar bawal. Parameter yang diukur didukung oleh parameter kualitas air. Analisis data menggunakan Analisis Varian (ANOVA) dan untuk menentukan perlakuan terbaik digunakan Duncan's multiple range test. Hasil penelitian menunjukkan perbedaan yang signifikan (p <0,05) dalam retensi protein dan energi adalah daging ikan bawal air tawar. Retensi protein dan retensi energi dalam pengobatan P1 (0,6% lisin), P2 (1,2% lisin), P3 (2,4% lisin) dan P4 (4,8% lisin) berbeda secara signifikan dengan perlakuan P0 (kontrol). Kualitas air selama 40 hari perlakuan ditetapkan pada suhu 27-300 C, pH 7,5-8,5, amonia 4 mg / l dan oksigen terlarut 4 mg / l. AbstractAmino acids are the smallest components that compose proteins. A number of amino acids will be conducted to one another through the intermediary of peptide bonds to form proteins. Amino acids have divided into two; those are essential amino acids and non-essential amino acids. The essential amino acids are amino acids that can not be synthesized by the body of fish; therefore the essential amino acids must be in feed. Lysine is one of the ten essentials amino acids , the function of lysine are for the growth and repair body tissues. This research was aimed to determine the effect of lysine in commercial feed on protein retention and energy retention of freshwater Bawal.The method used is experiment with a completely randomized design as an experimental design. The treatment used is different lysine levels , namely P0 ( 0 % ) , P1 ( 0.6 % ) , P2 ( 1.2 % ) , P3 ( 2.4 % ) , P4 (4.8 % ) and treatment was repeated 4 times. The main parameters were observed protein retention and energy retention on Bawal fresh water. Parameters measured were supported by water quality parameters. Analysis of the data using Analysis of Varian ( ANOVA ) and to determine the best treatment used Duncan 's multiple range test. The results showed the significant differences ( p < 0.05 ) in protein retention and energy were freshwater pomfret fish meat. Retention of protein and energy retention in treatment P1 ( 0.6 % lysine ) , P2 ( 1.2 % lysine ) , P3 ( 2.4 % lysine ) and P4 ( 4.8 % lysine ) was significantly different with treatment P0 ( control ). The quality of water for 40 days treatment was set to temperature 27-300 C, pH 7.5-8.5, ammonia 4 mg/l and dissolved oxygen 4 mg/l.

Download Full-text

Nutritional components of the sea cucumber Holothuria scabra

Functional Foods in Health and Disease ◽

10.31989/ffhd.v7i3.303 ◽

2017 ◽

Vol 7 (3) ◽

pp. 168 ◽

Cited By ~ 3

Author(s):

Morakot Sroyraya ◽

Peter J. Hanna ◽

Tanapan Siangcham ◽

Ruchanok Tinikul ◽

Prapaporn Jattujan ◽

...

Keyword(s):

Amino Acids ◽

Fatty Acids ◽

Stearic Acid ◽

Sea Cucumber ◽

Body Wall ◽

Essential Fatty Acids ◽

Essential Amino Acids ◽

Whole Body ◽

Holothuria Scabra ◽

Arachidonic Acids

Background: Holothuria scabra is one of the most commercially important species found in the Pacific region. The sea cucumber extracts have been widely reported to have beneficial health effects. The aim of this study was to determine the nutritional compositions of H. scabra, and compare its important nutritional contents with that of other species.Methods: The sea cucumbers were dissected, sliced into small pieces, and then freeze-dried. The nutritional compositions, including proximate composition, amino acids, fatty acids, collagen, GABA, Vitamin A, C, and E of the whole body and body wall of H. scabra, were analyzed.Results: H. scabra contained a high quantity of protein (22.50% in whole body and 55.18% in body wall) and very low lipids (1.55% in whole body and 1.02% in body wall). The three most abundant amino acids found in both the whole body and body wall were glycine, glutamic acid, and proline. The main fatty acids found in the whole body were stearic acid and nervonic acid, and in the body wall were arachidonic acid and stearic acid. The whole body and body wall also contained high levels of essential amino acids, essential fatty acids, and collagen, in addition to moderate amounts of vitamin E and low amounts of GABA and vitamin C.Conclusions: The sea cucumber, H. scabra, contained high quantity of protein and very low lipid. It contained high essential amino acids, essential fatty acids, nervonic and arachidonic acids, and collagen, which also contained GABA, vitamin C, and vitamin E.Keywords: sea cucumber; Holothuria scabra; nutrition components; functional food

Download Full-text

Nonessential amino acid usage for protein replenishment in humans: a method of estimation

American Journal of Clinical Nutrition ◽

10.1093/ajcn/nqz039 ◽

2019 ◽

Vol 110 (2) ◽

pp. 255-264 ◽

Cited By ~ 4

Author(s):

Paolo Tessari

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Protein Quality ◽

Essential Amino Acids ◽

World Health ◽

Whole Body ◽

Published Data ◽

Total Proteins ◽

Body Protein ◽

Amino Acid Turnover

ABSTRACT Background Essential amino acids (EAAs) are key factors in determining dietary protein quality. Their RDAs have been estimated. However, although nonessential amino acids (NEAAs) are utilized for protein synthesis too, no estimates of their usage for body protein replenishment have been proposed so far. Objective The aim of this study was to provide minimum, approximate estimates of NEAA usage for body protein replenishment/conservation in humans. Methods A correlation between the pattern of both EAAs and NEAAs in body proteins, and their usage, was assumed. In order to reconstruct an “average” amino acid pattern/composition of total body proteins (as grams of amino acid per gram of protein), published data of relevant human organs/tissues (skeletal muscle, liver, kidney, gut, and collagen, making up ∼74% of total proteins) were retrieved. The (unknown) amino acid composition of residual proteins (∼26% of total proteins) was assumed to be the same as for the sum of the aforementioned organs excluding collagen. Using international EAA RDA values, an average ratio of EAA RDA to the calculated whole-body EAA composition was derived. This ratio was then used to back-calculate NEAA usage for protein replenishment. The data were calculated also using estimated organ/tissue amino acid turnover. Results The individual ratios of World Health Organization/Food and Agriculture Organization/United Nations University RDA to EAA content ranged between 1.35 (phenylalanine + tyrosine) and 3.68 (leucine), with a mean ± SD value of 2.72 ± 0.81. In a reference 70-kg subject, calculated NEAA usage for body protein replenishment ranged from 0.73 g/d for asparagine to 3.61 g/d for proline. Use of amino acid turnover data yielded similar results. Total NEAA usage for body protein replenishment was ∼19 g/d (45% of total NEAA intake), whereas ∼24 g/d was used for other routes. Conclusion This method may provide indirect minimum estimates of the usage of NEAAs for body protein replacement in humans.

Download Full-text

Amino acids suppress proteolysis independent of insulin throughout the neonatal period

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1997.272.4.e592 ◽

1997 ◽

Vol 272 (4) ◽

pp. E592-E599 ◽

Cited By ~ 10

Author(s):

B. B. Poindexter ◽

C. A. Karn ◽

J. A. Ahlrichs ◽

J. Wang ◽

C. A. Leitch ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Neonatal Period ◽

Essential Amino Acids ◽

Whole Body ◽

Amino Acid Availability ◽

Dose Dependent Fashion ◽

Term Newborns ◽

Dose Dependent ◽

Acid Administration

To determine how increased amino acid availability alters rates of whole body proteolysis and the irreversible catabolism of the essential amino acids leucine and phenylalanine throughout the neonatal period, leucine and phenylalanine kinetics were measured under basal conditions and in response to intravenous amino acids in two separate groups of healthy, full-term newborns (at 3 days and 3 wk of age). The endogenous rates of appearance of leucine and phenylalanine (reflecting proteolysis) were suppressed equally in both groups and in a dose-dependent fashion (by approximately 10% with 1.2 g x kg(-1) x day(-1) and by approximately 20% with 2.4 g x kg(-1) x day(-1)) in response to intravenous amino acid delivery. Insulin concentrations remained unchanged from basal values during amino acid administration. The irreversible catabolism of leucine and phenylalanine increased in a stepwise fashion in response to intravenous amino acids; again, no differences were observed between the two groups. This study clearly demonstrates that the capacity to acutely increase rates of leucine oxidation and phenylalanine hydroxylation is fully present early in the neonatal period in normal newborns. Furthermore, these data suggest that amino acid availability is a primary regulator of proteolysis in normal newborns throughout the neonatal period.

Download Full-text

In vivo Determination of Amino Acid Bioavailability in Humans and Model Animals

Journal of AOAC International ◽

10.1093/jaoac/88.3.923 ◽

2005 ◽

Vol 88 (3) ◽

pp. 923-934 ◽

Cited By ~ 36

Author(s):

Malcolm F Fuller ◽

Daniel Tomé

Keyword(s):

Amino Acids ◽

Amino Acid ◽

The Body ◽

Whole Body ◽

Intestinal Lumen ◽

Stable Isotope Labelling ◽

Ileal Digestibility ◽

Hydrolyzed Protein ◽

Protein Free Diet

Abstract Because the digestion of many dietary proteins is incomplete, and because there is a continuous (but variable) entry into the intestinal lumen of endogenous protein and amino acid nitrogen that is also subject to digestion, the fluxes of nitrogen, amino acids, and protein in the gut exhibit a rather complicated pattern. Methods to distinguish and quantitate the endogenous and dietary components of nitrogen and amino acids in ileal chyme or feces include the use of a protein-free diet, the enzyme-hydrolyzed protein method, different levels of protein intake, multiple regression methods, and stable-isotope labelling of endogenous or exogenous amino acids. Assessment of bioavailability can be made, with varying degrees of difficulty, in man directly but, for routine evaluation of foods, the use of model animals is attractive for several reasons, the main ones being cost and time. Various animals and birds have been proposed as models for man but, in determining their suitability as a model, their physiological, enzymological, and microbiological differences must be considered. Fecal or ileal digestibility measurements, as well as apparent and true nitrogen and amino acid digestibility measurements, have very different nutritional significance and can, thus, be used for different objectives. Measurements at the ileal level are critical for determining amino acid losses of both dietary and endogenous origin, whereas measurements at the fecal level are critical in assessing whole-body nitrogen losses. A complementary and still unresolved aspect is to take into account the recycling of intestinal nitrogen and bacterial amino acids to the body.

Download Full-text

The case for regulating indispensable amino acid metabolism: the branched-chain α-keto acid dehydrogenase kinase-knockout mouse

Biochemical Journal ◽

10.1042/bj20061506 ◽

2006 ◽

Vol 400 (1) ◽

Cited By ~ 15

Author(s):

Susan M. Hutson

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Essential Amino Acids ◽

The Body ◽

Keto Acid ◽

Acid Dehydrogenase ◽

Indispensable Amino Acid ◽

Branched Chain

BCAAs (branched-chain amino acids) are indispensable (essential) amino acids that are required for body protein synthesis. Indispensable amino acids cannot be synthesized by the body and must be acquired from the diet. The BCAA leucine provides hormone-like signals to tissues such as skeletal muscle, indicating overall nutrient sufficiency. BCAA metabolism provides an important transport system to move nitrogen throughout the body for the synthesis of dispensable (non-essential) amino acids, including the neurotransmitter glutamate in the central nervous system. BCAA metabolism is tightly regulated to maintain levels high enough to support these important functions, but at the same time excesses are prevented via stimulation of irreversible disposal pathways. It is well known from inborn errors of BCAA metabolism that dysregulation of the BCAA catabolic pathways that leads to excess BCAAs and their α-keto acid metabolites results in neural dysfunction. In this issue of Biochemical Journal, Joshi and colleagues have disrupted the murine BDK (branched-chain α-keto acid dehydrogenase kinase) gene. This enzyme serves as the brake on BCAA catabolism. The impaired growth and neurological abnormalities observed in this animal show conclusively the importance of tight regulation of indispensable amino acid metabolism.

Download Full-text

Response of adult rats to deficiencies of different essential amino acids

British Journal Of Nutrition ◽

10.1079/bjn19740007 ◽

1974 ◽

Vol 31 (1) ◽

pp. 47-57 ◽

Cited By ~ 18

Author(s):

A. K. Said ◽

D. M. Hegsted ◽

K. C. Hayes

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Nutritive Value ◽

Plasma Concentrations ◽

Essential Amino Acids ◽

The Body ◽

Adult Rats ◽

Short Period ◽

Body Weights ◽

Fatty Livers

1. Adult rats were fed on diets free of either lysine, methionine, threonine or protein. The threonine- and protein-deficient animals lost weight at approximately the same rate, about 100 g in 14 weeks, at which time several were moribund. In contrast, lysine-deficient animals lost only about 30 g in 14 weeks and had lost only 46 g after 22 weeks, when they were killed. Methionine-deficient animals showed an intermediate response. Losses in weight of several tissues – kidney, heart and two muscles – were related to, but not necessarily proportional to, the loss of body-weight. Liver weights relative to body-weights were large in lysine- and threonine-deficient animals and smallest in methionine-deficient animals.2. Adult rats were fed on diets containing zero, a moderate amount (about twice the estimated minimal requirement) or an excess (about four times the estimated requirement) of lysine or threonine in all combinations (3 × 3 design). Analysis of variance of the body-weights, tissue weights and tissue nitrogen contents indicated, in general, a significant effect of each amino acid, as expected, but also, in most instances, a significant interaction. Plasma concentrations of lysine and threonine were affected by the intakes of the respective amino acids, but plasma lysine concentrations were also affected by the threonine intake.3. Liver histology also suggested significant interactions between the two amino acids. Animals given no lysine but moderate amounts of threonine developed severely fatty livers; next most severely affected were animals receiving excess of both amino acids. Threonine deficiency, in the presence or absence of lysine, produced moderately fatty livers similar to those seen in protein-deficient animals.4. Since animals have varying ability to conserve body nitrogen when they are fed on diets limiting in different essential amino acids, measurements of biological value (BV) and net protein utilization by conventional methods, over a short period of time, over-estimate nutritive value relative to amino acid score and probably over-estimate the true nutritive value of poor-quality proteins, particularly those limiting in lysine. If so, this is a serious error, since it leads to underestimates of the protein requirements if BV is used. The fact that certain tissues, particularly the liver, do not necessarily lose nitrogen in proportion to total body nitrogen and may show specific pathological effects depending on the limiting amino acid or the proportions of amino acids in the diet also indicates that general measures of nitrogen economy may not be sufficiently discriminating tests of the nutritive value of proteins.

Download Full-text

Leucine as a regulator of whole body and skeletal muscle protein metabolism in humans

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1992.263.5.e928 ◽

1992 ◽

Vol 263 (5) ◽

pp. E928-E934 ◽

Cited By ~ 50

Author(s):

K. S. Nair ◽

R. G. Schwartz ◽

S. Welle

Keyword(s):

Amino Acids ◽

Protein Degradation ◽

Protein Metabolism ◽

Muscle Protein ◽

Plasma Concentrations ◽

Essential Amino Acids ◽

Whole Body ◽

Skeletal Muscle Protein ◽

Muscle Protein Metabolism

Leucine has been proposed as an in vivo regulator of protein metabolism, although the evidence for this in humans remains inconclusive. To test this hypothesis, we infused either L-leucine (154 +/- 1 mumol.kg-1 x h-1) or saline intravenously in six healthy men in two separate studies. L-Leucine infusion increased plasma concentrations of leucine and alpha-ketoisocaproate from 112 +/- 6 and 38 +/- 3 mumol/l to 480 +/- 27 (P < 0.001) and 94 +/- 13 mumol/l (P < 0.001), respectively, without any significant change in circulating insulin or C peptide levels. Leucine infusion decreased plasma concentrations of several amino acids and decreased whole body valine flux and valine oxidation (using L-[1-13C]valine as a tracer) and phenylalanine flux (using [2H5]-phenylalanine as a tracer). According to arteriovenous differences across the leg, the net balance of phenylalanine, valine, and lysine shifted toward greater retention during leucine infusion, whereas alanine balance did not change. Valine release and phenylalanine release from the leg (estimated from the dilution of respective tracers) decreased, indicating inhibition of protein degradation by leucine infusion. We conclude that leucine decreases protein degradation in humans and that this decreased protein degradation during leucine infusion contributes to the decrease in plasma essential amino acids. This study suggests a potential role for leucine as a regulator of protein metabolism in humans.

Download Full-text

Advantages and limitations of the protein digestibility-corrected amino acid score (PDCAAS) as a method for evaluating protein quality in human diets

British Journal Of Nutrition ◽

10.1017/s0007114512002541 ◽

2012 ◽

Vol 108 (S2) ◽

pp. S333-S336 ◽

Cited By ~ 38

Author(s):

Gertjan Schaafsma

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Protein Quality ◽

Protein Digestibility ◽

Essential Amino Acids ◽

Tissue Growth ◽

Biological Efficiency ◽

Amino Acid Supplementation ◽

Reference Pattern ◽

Plant Protein Sources

PDCAAS is a widely used assay for evaluating protein quality. It is a chemical score, which is derived from the ratio between the first limiting amino acid in a test protein and the corresponding amino acid in a reference amino acid pattern and corrected for true faecal N digestibility. Chemical scores exceeding 100 % are truncated to 100 %. The advantages of the PDCAAS are its simplicity and direct relationship to human protein requirements. The limitations are as follows: the reference pattern is based on the minimum amino acid requirements for tissue growth and maintenance and does not necessarily reflect the optimum intake. Truncated PDCAAS of high-quality proteins do not give any information about the power of these proteins to compensate, as a supplement, for low levels of dietary essential amino acids in low-quality proteins. It is likely that faecal N digestibility does not take into account the loss from the colon of indispensable amino acids that were not absorbed in the ileum. Anti-nutritional factors, such as lectins and trypsin inhibitors, in several plant protein sources can cause heightened endogenous losses of amino acids, an issue which is particularly relevant in animal feedstuffs. The assumption that amino acid supplementation can completely restore biological efficiency of the protein source is incorrect since the kinetics of digestion and absorption between supplemented free amino acids and amino acids present in dietary proteins, are different.

Download Full-text

The fate of absorbed and exogenous ammonia as influenced by forage or forage–concentrate diets in growing sheep

British Journal Of Nutrition ◽

10.1079/bjn19960028 ◽

1996 ◽

Vol 76 (2) ◽

pp. 231-248 ◽

Cited By ~ 41

Author(s):

G. E. Lobley ◽

P. J. M. Weijs ◽

A. Connell ◽

A. G. Calder ◽

D. S. Brown ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Ammonium Salt ◽

Free Amino ◽

Essential Amino Acids ◽

Whole Body ◽

Minor Role ◽

N Removal ◽

A Minor ◽

Branched Chains

Changes in splanchnic energy and N metabolism were studied in sheep, prepared with vascular catheters across the portal-drained viscera (PDV) and the Liver, and maintained on supramaintenance intakes of either grass or grass + barley pellets. The animals were challenged, on both diets, with 4 d intra- mesenteric vein infusions of NH4CI (25 µmol/min) plus NH4HCO3(at either 0 or 125 µmol/min). On the final day of each treatment the natural abundance NH4Cl was replaced with15NH4Cl over a 10 h infusion while over the same period [l-13C]leucine was infused via a jugular vein. Measurements were made of blood flow plus mass transfers of NH3, urea, free amino acids and O2, across the PDV and liver. Enrichments of [14N15N]urea and [15N15N]urea plus [15N]glutamine, aspartate and glutamate were also monitored. Whole-body urea flux was determined by infusion of [14C]urea. At the end of the study the animals were infused for 3 h with15NH4CI, killed and liver samples assayed for intracellular free amino acid enrichments and concentrations. Blood flows across the splanchnic region were unaffected by either diet or level of ammonium salt infusion. At the lower ammonium salt infusion there was a trend for greater absorption of NH3across the PDV (P<0·10) with grass + barley than with the grass diet, while removal of urea was unaltered. At the higher ammonium salt infusions there was a significantly greater appearance of NH, across the PDV and this exceeded the extra infused. Urea-N removal, however, was also elevated and by more than that required to account for the additional NH3. The PDV contributed 19–28% to whole-body O2consumption and the liver 23–32%. Hepatic extraction of absorbed NH3was complete on all treatments and systemic pH remained constant. The fractions of urea-N apparently derived from NH3, were similar on the grass (0·59–0·64) and grass + barley (0·64–0·67) diets. Hepatic production of urea agreed well with urea flux measurements. Between the two levels of ammonium salt infusion and within diets the additional NH3removed across the PDV was accounted for by the increased urea-N production. The [14N15N]: [15N15N] ratio of the urea produced was 97:3, while the enrichment of hepatic intracellular free aspartate was lower than that of [14N15N]urea. Glutamine enrichments were 0·23–0·37 those of [14N15N]urea, indicating a minor role for those hepatocytes (probably perivenous) which contain glutamine synthetase (EC6.3.1.2). Leucine kinetics, either for the whole body or splanchnic tissues, were not different between diets or level of ammonium salt infusion, except for oxidation which was less on the grassfbarley ration. Amino acid concentrations were lower on the grass + barley diet but net PDV absorptions were similar. The pattern of essential amino acids absorbed into the PDV showed good agreement with the published composition of mixed rumen microbial protein. Fractional disappearances of absorbed free essential amino acids across the liver varied from 0·4 (branched chains) to near unity (histidine, phenylalanine)

Download Full-text