Hostname: page-component-8448b6f56d-tj2md Total loading time: 0 Render date: 2024-04-24T00:59:00.874Z Has data issue: false hasContentIssue false

Hepatic protein synthesis in the sheep: effect of intake as by use of stable-isotope-labelled glycine, leucine and phenylalanine

Published online by Cambridge University Press:  09 March 2007

A. Connell
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB21 9SB
A. G Calder
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB21 9SB
S. E Anderson
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB21 9SB
G. E Lobley*
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB21 9SB
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Rates of protein synthesis for the liver, plasma albumin and total plasma protein were quantified in sheep either offered a supra-maintenance intake or fasted for 3 d. The technique of continuous infusion over a 12 h period was employed with the simultaneous infusion of [1-13C]glycine, [1-13C]leucine and [2H5]phenylalanine. Blood and plasma samples were removed at timed intervals from the hepatic portal and hepatic veins plus the aorta. Enrichments of the free amino acids (AA) were determined in all blood and plasma samples as was the protein-bound AA in an apolipoprotein B100 extract. Protein-bound phenylalanine enrichments were also measured in albumin and total protein from plasma plus samples from liver biopsies. The apolipoprotein B100 enrichments agreed well with those of the free AA in hepatic (and hepatic portal) plasma but were lower than for arterial free AA and greater than liver homogenate free AA. This adds support to the concept that export proteins may preferentially use AA directly from extracellular sources. Intake had no significant effect on constitutive liver protein synthesis and the values agreed well with those obtained by other isotopic approaches. There were, however, signicant declines, based on hepatic venous free phenylalanine enrichment, at the lower intake in both the fractional (3·4v. 4·7 % per d; P=0·024) and absolute (2·4 v. 4·2 g/d; P=0·011) synthesis rates of albumin, which matched the estimated decrease in total plasma albumin content (52 v. 67 g, P <0·01). In contrast, there was a smaller reduction in total plasma protein mass (145 v. 151 g, P=0·035) with no observed significant difference in kinetic parameters. Albumin synthesis was calculated to account for a maximum of 17 % of total liver protein synthesis in the fed condition and this may fall to 8 % during moderate fasts.

Type
Animal Nutrition
Copyright
Copyright © The Nutrition Society 1997

References

REFERENCES

Abbott, E. M., Parkins, J. J. & Holmes, P. H. (1985). Influence of dietary protein on the pathophysiology of ovine haemonchosis in Finn Dorset and Scottish Blackface lambs given a single moderate infection. Research in Veterinary Science 38, 5460.CrossRefGoogle Scholar
Attaix, D., Aurousseau, E., Bayle, G., Manghebati, A. & Arnal, M. (1987). Protein synthesis and degradation in growing lambs. In 5th International Symposium on Protein Metabolism and Nutrition, EAAP Publication no. 35, pp 24-27,Rostock, Germany:Wilhelm-Pieck University.Google Scholar
Ballevre, O., Cadenhead, A., Calder, A. G., Rees, W. D., Lobley, G. E., Fuller, M. F. & Garlick, P. J. (1990). Quantitative partition of threonine oxidation in pigs: effect of dietary threonine. American Journal of Physiology 259, E483E491.Google ScholarPubMed
Ballmer, P. E., McNurlan, M. A., Essen, P., Anderson, S. E. & Garlick, P. J. (1995). Albumin synthesis rates measured with [2H5 ring]phenylalanine are not responsive to short-term intravenous nutrients in healthy humans. Journal of Nutrition 125, 512519.Google Scholar
Blanco-Vaca, F., Gaubatz, J. W., Bren, N., Kottke, B. A., Morrisett, J. D. & Guevara, J. Jr (1994). Indentification and quantification of apolipoproteins in addition to apo [a] and apo b-100 in human lipoprotein [a]. Chemistry and Physics of Lipids 67/68, 3542.CrossRefGoogle Scholar
Burrin, D. G., Ferrell, C. L., Britton, R. A. & Bauer, M. (1990). Level of nutrition and visceral organ size and metabolic activity in sheep. British Journal of Nutrition 64, 439448.CrossRefGoogle ScholarPubMed
Calder, A. G., Anderson, S. E., Grant, I., McNurlan, M. A. & Garlick, P. J. (1992). The determination of low d5phenylalanine enrichment (0·002-0·09 Atom Percent Excess) after conversion to phenylethylamine, in relation to protein turnover studies by gas chromatography (electron ionisation) mass spectrometry. Rapid Communications in Mass Spectrometry 6, 421424.CrossRefGoogle ScholarPubMed
Calder, A. G. & Smith, A. (1988). Stable isotope ratio analysis of leucine and ketoisocaproic acid in blood plasma by gas chromatography/mass spectrometry. Rapid Communications in Mass Spectrometry 2, 1416.CrossRefGoogle ScholarPubMed
Cayol, M., Capitan, P., Prugnaud, J., Genest, M., Beaufrere, B & Obled, C. (1995). Cation-exchange resins release amino acids: consequences for tracer studies. Analytical Biochemistry 227, 392394.CrossRefGoogle ScholarPubMed
Chalmers, M. I., Grant, I. & White, F. (1982). Free amino-nitrogen exchange across the hindquarters of fed and fasted sheep and pigs. Journal of Agricultural Science, Cambridge 99, 91104.CrossRefGoogle Scholar
Elwyn, D. M., Parikk, H. C. & Shoemaker, W. C. (1968). Amino acid movements between gut, liver and periphery in unanaesthetized dog. American Jouml of Physiology 215, 12601275.CrossRefGoogle Scholar
Fern, E. B. & Garlick, P. J. (1976). Compartmentation of albumin and ferritin synthesis in rat liver in vivo. Biochemical Journal 156, 189192.CrossRefGoogle ScholarPubMed
Fleck, A., Raines, G., Hawker, F., Trotter, J., Wallace, P. I., Ledingham, I. McA. & Calman, K. C. (1985). Increased vascular permeability: a major cause of hypoalbuminaemia in disease and injury. Lancet 1, 781784.CrossRefGoogle Scholar
Ford, G. D., Cheng, K. N. & Halliday, D. (1985). Analysis of [l-13C]leucine and [13C]KIC in plasma by capillary gas chromatography/mass spectrometry in protein turnover studies. Biomedical Mass Spectrometry 12, 432436.CrossRefGoogle ScholarPubMed
Garfinkel, D. & Lajtha, A. (1963). A metabolic inhomogeneity of glycine in vivo. 1. Experimental determination. Journal of Biological Chemistry 238, 24292439.CrossRefGoogle Scholar
Garlick, P. J., McNurlan, M. A., Essen, P. & Wernerman, J. (1994). Measurement of tissue protein synthesis rates in vivo: a critical analysis of contrasting methods. American Journal of Physiology 266, 287297.Google ScholarPubMed
Gornall, A. G., Bardawill, C. J. & David, M. M. (1949). Determination of serum proteins by means of the biuret reaction. Journal of Biological Chemistry 177, 751766.CrossRefGoogle ScholarPubMed
Harris, P. M., Lobley, G. E., Skene, P. A., Buchan, V., Calder, A. G., Anderson, S. E. & Connell, A. (1992). Effect of food intake on hind-limb and whole-body protein metabolism in young growing sheep: chronic studies based on arterio-venous techniques. British Journal of Nutrition 68, 388407.CrossRefGoogle ScholarPubMed
Haythorn, P. & Sheehan, M. (1979). Improved centrifugal analyzer assay of albumin. Clinical Chemistry 25, 194.CrossRefGoogle ScholarPubMed
Heitmann, R. N. & Bergman, E. N. (1980). Transport of amino acids in whole blood and plasma of sheep. American Journal of Physiology 239, E242E247.Google ScholarPubMed
Hesketh, J. (1994). Translation and the cytoskeleton: a mechanism for targeted protein synthesis. Molecular Biology Reports 19, 233243.CrossRefGoogle ScholarPubMed
Hunter, K. A., Ballmer, P. E.Anderson, S. E., Broom, J., Garlick, P. J. & McNurlan, M. A. (1995). Acute stimulation of albumin synthesis rate with oral meal feeding in healthy subjects measured with [ring-2H5]phenylalanine. Clinical Science 88, 235242.CrossRefGoogle ScholarPubMed
Kesaniemi, Y. A., Vega, G. L. & Grundy, S. M. (1982). Kinetics of apolipoprotein B in normal and hyperlipidemic man: review of current data. In Lipoprotein Kinetics and Modelling, pp. 181205. [Berman, M., Grundy, S. M. and Howard, B. V., editors]. New York: Academic Press.CrossRefGoogle Scholar
Krahenbuhl, S., Marti, U., Grant, I., Garlick, P. J. & Ballmer, P. E. (1995). Characterization of mechanisms causing hypoalbuminaemia in rats with long-term bile duct ligation. Journal of Hepatology 23, 7986.CrossRefGoogle ScholarPubMed
Laemli, U. K. (1970). Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227, 680685.CrossRefGoogle Scholar
Le Floc'h, N., Obled, C. & Seve, B. (1995). In vivo threonine oxidation rate is dependent on threonine dietary supply in growing pigs fed low to adequate levels. Journal of Nutrition 125, 25502562.Google ScholarPubMed
Lobley, G. E., Connell, A., Lomax, M. A., Brown, D. S., Milne, E., Calder, A. G. & Farningham, D. A. H. (1995). Hepatic detoxification of ammonia in the ovine liver: possible consequences for amino acid catabolism. British Journal of Nutrition 73, 667685.CrossRefGoogle ScholarPubMed
Lobley, G. E., Connell, A., Milne, E., Newman, A. M. & Ewing, T. A. (1994). Protein synthesis in splanchnic tissues of sheep offered two levels of intake. British Journal of Nutrition 71, 312.CrossRefGoogle ScholarPubMed
Lobley, G. E., Connell, A., Revell, D. K., Brown, D. S. & Calder, A. G. (1996). Splanchnic-bed transfers of amino acids in sheep blood and plasma, as monitored through use of a multiple U-13C-labelled amino acid mixture. British Journal of Nutrition 75, 217235.CrossRefGoogle ScholarPubMed
MacKenzie, S. L. & Tenaschuk, D. (1979). Quantitative formation of N(O,S)-heptalluorobutyryl isobutyl amino acids for gas chromatographic analysis. II. Acylation. Journal of Chromatography 173, 5463.CrossRefGoogle Scholar
McNurlan, M. A., Tomkins, A. M. & Garlick, P. J. (1979). The effect of starvation on the rate of protein synthesis in rat liver and small intestine. Biochemical Journal 178, 373379.CrossRefGoogle ScholarPubMed
MacRae, J. C., Walker, A., Brown, D. & Lobley, G. E. (1993). Accretion of total protein and individual amino acids by organs and tissues of growing lambs and the ability of nitrogen balance techniques to quantitate protein retention. Animal Production 57, 237245.Google Scholar
Merry, B. J., Holehan, A. M., Lewis, S. E. M. & Goldspink, D. F. (1987). The effects of ageing and chronic dietary restriction on in vivo hepatic protein synthesis in the rat. Mechanisms of Ageing and Development 39, 189199.CrossRefGoogle ScholarPubMed
Milano, G. D. (1994). Consequences of ammonia metabolism across splanchnic tissues in fasted sheep. MSc Thesis, University of Aberdeen.Google Scholar
Mortimore, G. E. & Sunmacz, C. A. (1984). Liver perfusion: an in vitro technique for the study of intracellular protein turnover and its regulation in vivo. Proceedings of the Nutrition Society 43, 161167.CrossRefGoogle Scholar
Motil, K. J., Opekun, A. R., Montandon, C. M., Berhold, H. K., Davis, T. A., Klein, P. D. & Reeds, P. J. (1994). Leucine oxidation changes rapidly after dietary protein intake is altered in adult women but lysine flux is unchanged as is lysine incorporation into VLDL-apolipoprotein B-100. Journal of Nutrition 124, 4151.CrossRefGoogle ScholarPubMed
Papet, I., Glomot, F., Grizard, J. & Arnal, M. (1992). Leucine excess under conditions of low or compensated aminoacidemia does not change skeletal muscle and whole body protein synthesis in suckling lambs during postprandial period. Journal of Nutrition 122, 23072315.CrossRefGoogle Scholar
Patterson, B. W., Hachey, D. L., Cook, G. I., Amann, J. M. & Klein, P. D. (1991). Incorporation of a stable isotopically labelled amino acid into multiple human apolipoproteins. Journal of Lipid Research 32, 10631072.CrossRefGoogle ScholarPubMed
Pell, J. M., Calderone, E. M. & Bergman, E. N. (1986). Leucine and α-ketoisocaproate metabolism and interconversions in fed and fasted sheep. Metabolism 35, 10051016.CrossRefGoogle ScholarPubMed
Peters, T. P. & Peters, J. C. (1972). The biosynthesis of rat serum albumin. VI. Intracellular transport of albumin and rates of albumin and liver protein synthesis in vivo under various physiological conditions. Journal of Biological Chemistry 247, 38583863.CrossRefGoogle ScholarPubMed
Pinnel, A. E. & Northam, B. E. (1978). New automated dye-binding method for serum albumin determination with bromocresol purple. Clinical Chemistry 24, 8086.CrossRefGoogle Scholar
Pownall, M. J. & Gotto, A. M. (1992). Lipid metabolism and the plasma lipoproteins. In The Heart and the Cardiovascular System, 2nd ed., pp. 197205 [Fozzard, H. A., Haber, E., Jennings, R. B., Katz, A. M. and Morgan, H. E. editors]. New York: Raven.Google Scholar
Preedy, V. R., Paska, L., Sugden, P.H.Schofield, P.S. & Sugden, M.C. (1988). The effects of surgical stress and short-term fasting on protein synthesis in vivo in diverse tissues of the mature rat. Biochemical Journal 250, 179188.CrossRefGoogle ScholarPubMed
Reeds, P. J., Hachey, D. L., Patterson, B. W., Motil, K. J. & Klein, P. D. (1992). VLDL apolipoprotein B-100, a potential indicator of the isotopic labelling of the hepatic protein synthetic precursor pool in humans: studies with multiple stable isotopically labelled amino acids. Journal of Nutrition 122, 475–466.CrossRefGoogle Scholar
Rennie, M. J., Smith, K. & Watt, P. W. (1994). Measurement of human tissue protein synthesis: an optimal approach. American Journal of Physiology 266, E298E307.Google ScholarPubMed
Rérat, A., Simoes-Nuñes, C., Mendy, F., Vaissade, P. & Vaugelade, P. (1992). Splanchnic fluxes of amino acids after duodenal infusion of carbohydrate solutions containing free amino acids or oligopeptides in the non-anaesthetized pig. British Journal of Nutrition 68, 111138.CrossRefGoogle ScholarPubMed
Reynolds, C. K., Tyrrell, H. F. & Reynolds, P. J. (1991). Effects of diet forage-to-concentrate ratio and intake on energy metabolism in growing beef heifers: net nutrient metabolism by visceral tissues. Journal of Nutrition 121, 10041015.CrossRefGoogle ScholarPubMed
Rothschild, M. A., Oratz, M., Mongelli, J. & Schreiber, S. S. (1968). Effects of a short-term fast on albumin synthesis studied in vivo in the perfused liver and on amino acid incorporation by hepatic microsomes. Journal of Clinical Investigation 47, 25912599.CrossRefGoogle ScholarPubMed
Schirmer, M. D. & Harper, A. E. (1970). Adaptive response of mammalian histidine-degrading enzymes. Journal of Biological Chemistry 245, 12041211.CrossRefGoogle ScholarPubMed
Smith, C. B. & Sun, Y. (1995). Influence of valine flooding on channelling of valine into tissue pools and on protein synthesis. American Journal of Physiology 268, E735E744.Google ScholarPubMed
Smith, K., Barua, J. M., Watt, P. W., Scrimgeour, C. M. & Rennie, M. (1992). Flooding with L-[l-13C]leucine stimulates human muscle protein incorporation of continuously infused L-[l-13C]valine. American Journal of Physiology 266, E372E376.Google Scholar
Tauveron, I., Larbaud, D., Champredon, C., Debras, E., Tesseraud, S., Bayle, G., Bonnet, Y., Thieblot, P. & Grizard, J. (1994). Effect of hyperinsulinemia and hyperaminoacidemia on muscle and liver protein synthesis in lactating goats. American Journal of Physiology 267, E877E885.Google ScholarPubMed
Yap, S. J. & Hafkenscheid, J. C. M. (1981). Effect of starvation on the synthesis rate of albumin in vivo and its relation to the concentrations of amino acids in the peripheral blood, the portal circulation and in the liver cytosolic fraction. Annals of Nutrition and Metabolism 25, 158164.CrossRefGoogle Scholar
Young, V. R., Gucalp, C., Rand, W. M., Matthews, D. E. & Bier, D. M. (1987). Leucine kinetics during three weeks at submaintenance-to-maintenance intakes of leucine in man: adaptation and accommodation. Human Nutrition: Clinical Nutrition 41C, 118.Google Scholar