Insulin and incorporation of amino acids into protein of muscle. Cellular amino acid levels and aminoisobutyric acid uptake

1. The preparation of cell suspensions by treatment of chick embryo hearts with collagenase at various stages of development is described. 2. Measurements of oxygen consumption, incorporation of labelled leucine into protein and accumulation of labelled α-aminoisobutyric acid against a concentration gradient indicated a long-lasting viability of the isolated heart cells in vitro; a satisfactory preservation of subcellular structures, including plasma membrane, was assessed by electron-microscopic examination. 3. The rate of α-aminoisobutyric acid accumulation by cardiac cells isolated from hearts at different stages of embryological development decreased with aging; insulin stimulated the intracellular accumulation of this amino acid analogue. 4. Insulin increased the uptake by isolated heart cells of several 14C-labelled naturally occurring amino acids; however, the fraction of amino acid taken up by the cells that was recovered free intracellularly, and therefore the concentration ratio (between intracellular water and medium), was enhanced by the hormone only with glycine, proline, serine, threonine, histidine and methionine. When isolated heart cells were incubated in the presence of a mixture of labelled amino acids, the addition of insulin increased the disappearance of radioactivity from the medium. 5. The general pattern of amino acid transport (in the absence and in the presence of insulin) in isolated cardiac cells was similar to that found in intact hearts, suggesting that the biological preparation described in this paper might be useful for studies of cell permeability and insulin action.

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Puromycin effect on amino acid transport: differential rates of carrier protein turnover

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1975.228.1.23 ◽

1975 ◽

Vol 228 (1) ◽

pp. 23-26 ◽

Cited By ~ 6

Author(s):

JM Phang ◽

DL Valle ◽

L Fisher ◽

A Granger

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Transport ◽

Half Life ◽

Transport Systems ◽

Acid Uptake ◽

Acid Transport ◽

Aminoisobutyric Acid ◽

Fetal Rat ◽

Protein Components

In fetal rat calvaria, puromycin selectively inhibited the uptake of certain groups of amino acids. Puromycin treatment decreased the uptake of glycine, L-proline, and alpha-aminoisobutyric acid but was without effect on the active uptake of all other amino acids tested. In studies of alpha-aminoisobutyric acid uptake, puromycin decreased the maximal transport velocity by 70% but had no effect on the affinity of the transport system for the amino acid. With puromycin treatment, the fall-off in rates of alpha-aminoisobutyric acid uptake was first order with a half-life of 68 min. Insulin treatment increased this half-life to 118 min. These findings suggest that protein components of specific transport systems are degraded at varying rates after puromycin blockade of protein synthesis. Hormones that stimulate amino acid transport (e.g., insulin) may decrease the rate of degradation of these protein components.

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Gamma-Glutamyl-Amino Acids as Signals for the Hormonal Regulation of Amino Acid Uptake by the Mammary Gland of the Lactating Rat

Neonatology ◽

10.1159/000242178 ◽

1985 ◽

Vol 48 (4) ◽

pp. 250-256 ◽

Cited By ~ 8

Author(s):

Juan R. Viña ◽

Inmaculada R. Puertes ◽

Juan B. Montoro ◽

Guillermo T. Saez ◽

José Viña

Keyword(s):

Amino Acids ◽

Mammary Gland ◽

Amino Acid ◽

Hormonal Regulation ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Gamma Glutamyl

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Interrelationship between hepatic ureagenesis and gluconeogenesis in early sepsis

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1991.260.3.e453 ◽

1991 ◽

Vol 260 (3) ◽

pp. E453-E458 ◽

Cited By ~ 3

Author(s):

Y. Ohtake ◽

M. G. Clemens

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Substrate Preference ◽

Hormone Sensitivity ◽

Urea Production ◽

Urea Release ◽

Amino Acid Levels ◽

Early Sepsis ◽

Septic Group

This study was performed to investigate the interrelationship between gluconeogenesis and ureagenesis during sepsis. In isolated perfused livers, gluconeogenesis was assessed using either lactate or a combination of lactate, glutamine, and alanine as substrate. Ureagenesis was assessed using either NH4Cl or glutamine plus alanine as substrate. NH4Cl stimulated urea production in livers from both septic and sham-operated control rats. Urea release was approximately 1.2 and 2.0 mg urea nitrogen.g-1.h-1 for 1 and 5 mM NH4Cl, respectively, and was equal for both groups. With amino acids as substrate, urea production was significantly greater in livers from septic animals compared with controls. Phenylephrine stimulated urea production in the sham-operated group by about twofold, whereas in the septic group urea release was slightly inhibited. Gluconeogenesis from lactate was inhibited by NH4Cl (1 and 5 mM) in both groups, with no difference between groups. In contrast to enhanced ureagenesis from amino acids in septic rats, gluconeogenesis was decreased by approximately 24% (P less than 0.5). Similarly, phenylephrine (1 microM) stimulated gluconeogenesis by 13 +/- 1 mumol.g-1.h-1 in sham-operated rats but only by 9 +/- 1 mumol.g-1.h-1 in septic rats (P less than 0.02). These results suggest that hepatic gluconeogenic and ureagenic pathways are intact in sepsis but that altered substrate preference and hormone sensitivity may result in decreased gluconeogenesis in the presence of elevated amino acid levels.

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Action of growth hormone in vitro on the net uptake and incorporation into protein of amino acids in muscle from intact rabbits given protein-deficient diets

British Journal Of Nutrition ◽

10.1079/bjn19760003 ◽

1976 ◽

Vol 35 (1) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

M. R. Turner ◽

P. J. Reeds ◽

K. A. Munday

Keyword(s):

Amino Acids ◽

Growth Hormone ◽

Protein Synthesis ◽

Amino Acid ◽

De Novo ◽

Amino Acid Uptake ◽

Acid Uptake ◽

Amino Acid Incorporation ◽

Acid Incorporation

1. Net amino acid uptake, and incorporation into protein have been measured in vitro in the presence and absence of porcine growth hormone (GH) in muscle from intact rabbits fed for 5 d on low-protein (LP), protein-free (PF) or control diets.2. In muscle from control and LP animals GH had no effect on the net amino acid uptake but stimulated amino acid incorporation into protein, although this response was less in LP animals than in control animals.3. In muscle from PF animals, GH stimulated both amino acid incorporation into protein and the net amino acid uptake, a type of response which also occurs in hypophysectomized animals. The magnitude of the effect of GH on the incorporation of amino acids into protein was reduced in muscle from PF animals.4. The effect of GH on the net amino acid uptake in PF animals was completely blocked by cycloheximide; the uptake effect of GH in these animals was dependent therefore on de novo protein synthesis.5. It is proposed that in the adult the role of growth hormone in protein metabolism is to sustain cellular protein synthesis when there is a decrease in the level of substrate amino acids, similar to that which occurs during a short-term fast or when the dietary protein intake is inadequate.

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The uptake of amino acids by mouse cells (strain LS) during growth in batch culture and chemostat culture: the influence of cell growth rate

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1967.0073 ◽

1967 ◽

Vol 168 (1013) ◽

pp. 421-438 ◽

Cited By ~ 46

Keyword(s):

Amino Acids ◽

Growth Rate ◽

Amino Acid ◽

Cell Growth ◽

Glutamic Acid ◽

Batch Culture ◽

Amino Acid Uptake ◽

Essential Amino Acids ◽

Growth Yields ◽

Acid Uptake

The uptake of thirteen essential amino acids by mouse LS cells in suspension culture was determined by bacteriological assay methods. Chemostat continuous-flow cultures were used to determine the effect of different cell growth rates on the quantitative amino acid requirements for growth. The growth yields of the cells ( Y = g cell dry weight produced/g amino acid utilized) were calculated for each of the essential amino acids. A mixture of the non-essential amino acids, serine, alanine and glycine increased the cell yield from the essential amino acids. The growth yields from nearly all the essential amino acids in batch culture were increased when glutamic acid was substituted for the glutamine in the medium. The growth yields from the amino acids in batch culture were much less at the beginning than at the end of the culture. The highest efficiencies of conversion of amino acids to cell material were obtained by chemostat culture. When glutamic acid largely replaced the glutamine in the medium the conversion of amino acid nitrogen to cell nitrogen was 100 % efficient (that is, the theoretical yield was obtained) at the optimum growth rate (cell doubling time, 43 h). The maximum population density a given amino acid mixture will support can be calculated from the data. It is concluded that in several routinely used tissue culture media the cell growth is limited by the amino acid supply. In batch culture glutamine was wasted by (1) its spontaneous decomposition to pyrrolidone carboxylic acid and ammonia, and (2) its enzymic breakdown to glutamic acid and ammonia, but also glutamine was used less efficiently than glutamic acid. Study of the influence of cell growth rate on amino acid uptake rates per unit mass of cells indicated that a marked change in amino acid metabolism occurred at a specific growth rate of 0.4 day -1 (cell doubling time, 43 h). With decrease in specific growth rate below 0.4 day -1 there was a marked stimulation of amino acid uptake rate per cell and essential amino acids were consumed increasingly for functions other than synthesis of cell material.

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Amino acids whose intracellular levels change most during aging alter chronological lifespan of fission yeast

10.1101/2020.08.18.256164 ◽

2020 ◽

Author(s):

Charalampos Rallis ◽

Michael Mülleder ◽

Graeme Smith ◽

Yan Zi Au ◽

Markus Ralser ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Fission Yeast ◽

Yeast Cells ◽

Total Amino Acid ◽

Wild Type ◽

Chronological Lifespan ◽

Biomarkers Of Aging ◽

Concentration Changes ◽

Amino Acid Levels

AbstractAmino acid deprivation or supplementation can affect cellular and organismal lifespan, but we know little about the role of concentration changes in free, intracellular amino acids during aging. Here, we determine free amino-acid levels during chronological aging of non-dividing fission yeast cells. We compare wild-type with long-lived mutant cells that lack the Pka1 protein of the protein kinase A signalling pathway. In wild-type cells, total amino-acid levels decrease during aging, but much less so in pka1 mutants. Two amino acids strongly change as a function of age: glutamine decreases, especially in wild-type cells, while aspartate increases, especially in pka1 mutants. Supplementation of glutamine is sufficient to extend the chronological lifespan of wild-type but not of pka1Δ cells. Supplementation of aspartate, on the other hand, shortens the lifespan of pka1Δ but not of wild-type cells. Our results raise the possibility that certain amino acids are biomarkers of aging, and their concentrations during aging can promote or limit cellular lifespan.

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Action of insulin and growth hormone on protein synthesis in muscle from non-hypophysectomized rabbits

Biochemical Journal ◽

10.1042/bj1250515 ◽

1971 ◽

Vol 125 (2) ◽

pp. 515-520 ◽

Cited By ~ 13

Author(s):

P. J. Reeds ◽

K. A. Munday ◽

M. R. Turner

Keyword(s):

Amino Acids ◽

Growth Hormone ◽

Protein Synthesis ◽

Amino Acid ◽

Incubation Medium ◽

Amino Acid Uptake ◽

Diaphragm Muscle ◽

Acid Uptake

The separate effects of insulin and growth hormone on the uptake and incorporation of five amino acids into diaphragm muscle from non-hypophysectomized rabbits has been examined. Both growth hormone and insulin, when present in the medium separately, stimulated the incorporation into protein of the amino acids, leucine, arginine, valine, lysine and histidine. Insulin also stimulated amino acid uptake, but growth hormone did not. When insulin and growth hormone were present in the incubation medium together, the uptake and incorporation of valine, the only amino acid studied under these conditions, tended to be greater than the sum of the separate effects of the two hormones.

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Amino acid uptake systems in Bacteroides ruminicola

Canadian Journal of Microbiology ◽

10.1139/m79-180 ◽

1979 ◽

Vol 25 (10) ◽

pp. 1161-1168 ◽

Cited By ~ 15

Author(s):

Roselynn M. W. Stevenson

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Nitrogen Sources ◽

Amino Acid Uptake ◽

Defined Medium ◽

High Rate ◽

Transport Systems ◽

Acid Uptake ◽

Chemical Structures ◽

Kinetic Inhibition

Uptake of amino acids by Bacteroides ruminicola was observed in cells grown in a complete defined medium, containing ammonia as the nitrogen source. A high rate of uptake occurred only in fresh medium, as an inhibitory substance, possibly acetate, apparently accumulated during growth. All amino acids except proline were taken up and incorporated into cold trichloroacetic acid precipitable material. Different patterns of incorporation and different responses to 2,4-dinitrophenol and potassium ferricyanide indicated multiple uptake systems were involved. Kinetic inhibition patterns suggested six distinct systems were present for amino acid uptake, with specificities related to the chemical structures of the amino acids. Thus, the failure of free amino acids to act as sole nitrogen sources for growth of B. ruminicola is not due to the absence of transport systems for these compounds.

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Rhizobium leguminosarum Has a Second General Amino Acid Permease with Unusually Broad Substrate Specificity and High Similarity to Branched-Chain Amino Acid Transporters (Bra/LIV) of the ABC Family

Journal of Bacteriology ◽

10.1128/jb.184.15.4071-4080.2002 ◽

2002 ◽

Vol 184 (15) ◽

pp. 4071-4080 ◽

Cited By ~ 76

Author(s):

A. H. F. Hosie ◽

D. Allaway ◽

C. S. Galloway ◽

H. A. Dunsby ◽

P. S. Poole

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Rhizobium Leguminosarum ◽

Binding Protein ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Amino Acid Permease ◽

Branched Chain Amino Acid ◽

General Amino Acid Permease ◽

Branched Chain

ABSTRACT Amino acid uptake by Rhizobium leguminosarum is dominated by two ABC transporters, the general amino acid permease (Aap) and the branched-chain amino acid permease (BraRl). Characterization of the solute specificity of BraRl shows it to be the second general amino acid permease of R. leguminosarum. Although BraRl has high sequence identity to members of the family of hydrophobic amino acid transporters (HAAT), it transports a broad range of solutes, including acidic and basic polar amino acids (l-glutamate, l-arginine, and l-histidine), in addition to neutral amino acids (l-alanine and l-leucine). While amino and carboxyl groups are required for transport, solutes do not have to be α-amino acids. Consistent with this, BraRl is the first ABC transporter to be shown to transport γ-aminobutyric acid (GABA). All previously identified bacterial GABA transporters are secondary carriers of the amino acid-polyamine-organocation (APC) superfamily. Also, transport by BraRl does not appear to be stereospecific as d amino acids cause significant inhibition of uptake of l-glutamate and l-leucine. Unlike all other solutes tested, l-alanine uptake is not dependent on solute binding protein BraCRl. Therefore, a second, unidentified solute binding protein may interact with the BraDEFGRl membrane complex during l-alanine uptake. Overall, the data indicate that BraRl is a general amino acid permease of the HAAT family. Furthermore, BraRl has the broadest solute specificity of any characterized bacterial amino acid transporter.

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