scholarly journals Effect of metabolizable protein intake on rates of plasma leucine turnover and protein synthesis in heifers

2007 ◽  
Vol 146 (3) ◽  
pp. 343-349 ◽  
Author(s):  
H. SANO ◽  
M. KAJITA ◽  
M. ITO ◽  
T. FUJITA ◽  
A. TAKAHASHI
Keyword(s):  
Protein Synthesis ◽  
Soybean Meal ◽  
Open Circuit ◽  
Metabolizable Energy ◽  
Whole Body ◽  
Isotope Dilution Method ◽  
Dilution Method ◽  
Body Protein ◽  
Oxidation Rates ◽  
Metabolizable Protein

SUMMARYAn isotope dilution method using [1-13C]leucine (Leu) infusion together with open-circuit calorimetry was applied to determine the effect of metabolizable protein (MP) intake on rates of plasma Leu turnover and whole body protein synthesis (WBPS) in six heifers. WBPS rate was estimated from rate of plasma Leu turnover and Leu oxidation to carbon dioxide. The experiment consisted of three levels of MP intake and was conducted in a two 3×3 Latin square designs of three 21-day periods. The experimental diet consisted of mixed hay, maize and soybean meal. Dietary MP intake of each dietary treatment was 4·3, 4·5 and 4·9 g/kg BW0·75/day by changing maize and soybean meal weights. Metabolizable energy (ME) intake was similar for all dietary treatments. When plasma α-[1-13C]keto-isocaproic acid enrichments were used as markers indicating intracellular Leu enrichments, plasma Leu turnover rate (LeuTR) increased (P=0·012) and WBPS tended to increase (P=0·091) as MP intake increased. In contrast, plasma LeuTR and WBPS were not influenced if plasma [1-13C]Leu was taken to indicate intracellular Leu enrichments. Total and plasma Leu oxidation rates did not change but intracellular Leu oxidation increased (P=0·044) with increasing MP intake. In heifers, it is suggested that rates of plasma Leu turnover and WBPS are influenced by dietary MP intake, independent of ME intake, although the change in MP intake was relatively small.

Effects of diet and cold exposure on rates of plasma leucine turnover and protein synthesis in sheep

2008 ◽  
Vol 147 (1) ◽  
pp. 91-97 ◽  
Author(s):  
H. SANO ◽  
H. SAWADA ◽  
A. TAKENAMI ◽  
M. AL-MAMUN
Keyword(s):  
Protein Synthesis ◽  
Cold Exposure ◽  
Open Circuit ◽  
Metabolizable Energy ◽  
Whole Body ◽  
Environment Interaction ◽  
Body Protein ◽  
Intake Level ◽  
Metabolizable Energy Intake ◽  
Diet Intake

SUMMARYDilution of [1-13C]leucine (Leu) and open-circuit calorimetry were used to determine the effects of diet and cold exposure on rates of plasma Leu turnover, Leu oxidation, and whole body protein synthesis (WBPS) in sheep. The experiment was designed as a crossover design for two 23-day periods. Six adult sheep were assigned to two dietary treatments, medium (Me-diet) and high (Hi-diet) intake, and were fed either 515 or 830 kJ/kg BW0·75per day of metabolizable energy intake, respectively. The temperature in the chamber was changed from a thermoneutral environment (23°C) to a cold environment (2–4°C) for 5 days (the 18th to 23rd day of the experiment). Turnover rate of both plasma Leu and WBPS were greater (P<0·01) for the Hi-diet compared with the Me-diet and increased (P<0·01) during cold exposure. Leucine oxidation rate was numerically greater (P=0·10) for the Hi-diet compared with the Me-diet and increased (P=0·03) during cold exposure. No significant diet×environment interaction was detected in the rates of plasma Leu turnover, Leu oxidation or WBPS. It is concluded that plasma Leu kinetics and WBPS were influenced by intake level and increased during cold exposure, but the responses to cold exposure were not modified by intake level in sheep under the conditions of the present experiment.

Epidural Ropivacaine versus  Epidural Morphine and the Catabolic Response to Colonic Surgery

2004 ◽  
Vol 100 (4) ◽  
pp. 973-978 ◽  
Author(s):  
Thomas Schricker ◽  
Linda Wykes ◽  
Leopold Eberhart ◽  
Ralph Lattermann ◽  
Franco Carli
Keyword(s):  
Protein Synthesis ◽  
Epidural Analgesia ◽  
Protein Oxidation ◽  
Glucose Production ◽  
Whole Body ◽  
Protein Breakdown ◽  
Body Protein ◽  
Oxidation Rates ◽  
Metabolic Substrates ◽  
Catabolic Response

Background The authors examined the hypothesis that epidural administration of local anesthetic, in contrast to epidural analgesia with morphine, inhibits postoperative protein oxidation during administration of glucose. Methods Fourteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding with 4 mg.kg(-1).min(-1) glucose) on the second day after colorectal surgery using epidural analgesia with either continuous ropivacaine or intermittent morphine. Protein synthesis, breakdown and oxidation, and glucose production were measured by L-[L-13C]leucine and [6,6-2H2]glucose. Substrate oxidation rates were determined by indirect calorimetry. Plasma concentrations of metabolic substrates and hormones were also measured. Results Whole body protein breakdown, oxidation, synthesis, and glucose production in the fasted state were similar between the two groups. Glucose administration decreased protein breakdown (P = 0.01), protein synthesis (P = 0.001), and glucose production (P = 0.001) to the same extent in both groups, whereas protein oxidation was not significantly affected. The type of epidural analgesia did not significantly influence the circulating concentrations of metabolic substrates and hormones in the fasted or in the fed state. Carbohydrate oxidation rate in the ropivacaine group was greater than in patients receiving morphine (P = 0.04), regardless of whether glucose was infused. Conclusion Epidural analgesia achieved with ropivacaine or morphine does not suppress the catabolic response to surgery, either under fasting conditions or in the presence of an energy supply.

Impact of protein coingestion on muscle protein synthesis during continuous endurance type exercise

2011 ◽  
Vol 300 (6) ◽  
pp. E945-E954 ◽  
Author(s):  
Milou Beelen ◽  
Antoine Zorenc ◽  
Bart Pennings ◽  
Joan M. Senden ◽  
Harm Kuipers ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Muscle Protein ◽  
Protein Hydrolysate ◽  
Muscle Protein Synthesis ◽  
Whole Body ◽  
Body Protein ◽  
Oxidation Rates ◽  
Breakdown Rates ◽  
The Impact ◽  
Muscle Biopsies

This study investigates the impact of protein coingestion with carbohydrate on muscle protein synthesis during endurance type exercise. Twelve healthy male cyclists were studied during 2 h of fasted rest followed by 2 h of continuous cycling at 55% Wmax. During exercise, subjects received either 1.0 g·kg−1·h−1 carbohydrate (CHO) or 0.8 g·kg−1·h−1 carbohydrate with 0.2 g·kg−1·h−1 protein hydrolysate (CHO+PRO). Continuous intravenous infusions with l-[ ring-13C6]phenylalanine and l-[ ring-2H2]tyrosine were applied, and blood and muscle biopsies were collected to assess whole body protein turnover and muscle protein synthesis rates at rest and during exercise conditions. Protein coingestion stimulated whole body protein synthesis and oxidation rates during exercise by 22 ± 3 and 70 ± 17%, respectively ( P < 0.01). Whole body protein breakdown rates did not differ between experiments. As a consequence, whole body net protein balance was slightly negative in CHO and positive in the CHO+PRO treatment (−4.9 ± 0.3 vs. 8.0 ± 0.3 μmol Phe·kg−1·h−1, respectively, P < 0.01). Mixed muscle protein fractional synthetic rates (FSR) were higher during exercise compared with resting conditions (0.058 ± 0.006 vs. 0.035 ± 0.006%/h in CHO and 0.070 ± 0.011 vs. 0.038 ± 0.005%/h in the CHO+PRO treatment, respectively, P < 0.05). FSR during exercise did not differ between experiments ( P = 0.46). We conclude that muscle protein synthesis is stimulated during continuous endurance type exercise activities when carbohydrate with or without protein is ingested. Protein coingestion does not further increase muscle protein synthesis rates during continuous endurance type exercise.

Coingestion of carbohydrate with protein does not further augment postexercise muscle protein synthesis

2007 ◽  
Vol 293 (3) ◽  
pp. E833-E842 ◽  
Author(s):  
René Koopman ◽  
Milou Beelen ◽  
Trent Stellingwerff ◽  
Bart Pennings ◽  
Wim H. M. Saris ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Plasma Glucose ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Whole Body ◽  
Synthesis Rate ◽  
Vastus Lateralis Muscle ◽  
Body Protein ◽  
Oxidation Rates ◽  
The Impact

The present study was designed to assess the impact of coingestion of various amounts of carbohydrate combined with an ample amount of protein intake on postexercise muscle protein synthesis rates. Ten healthy, fit men (20 ± 0.3 yr) were randomly assigned to three crossover experiments. After 60 min of resistance exercise, subjects consumed 0.3 g·kg−1·h−1 protein hydrolysate with 0, 0.15, or 0.6 g·kg−1·h−1 carbohydrate during a 6-h recovery period (PRO, PRO + LCHO, and PRO + HCHO, respectively). Primed, continuous infusions with l-[ ring-13C6]phenylalanine, l-[ ring-2H2]tyrosine, and [6,6-2H2]glucose were applied, and blood and muscle samples were collected to assess whole body protein turnover and glucose kinetics as well as protein fractional synthesis rate (FSR) in the vastus lateralis muscle over 6 h of postexercise recovery. Plasma insulin responses were significantly greater in PRO + HCHO compared with PRO + LCHO and PRO (18.4 ± 2.9 vs. 3.7 ± 0.5 and 1.5 ± 0.2 U·6 h−1·l−1, respectively, P < 0.001). Plasma glucose rate of appearance (Ra) and disappearance (Rd) increased over time in PRO + HCHO and PRO + LCHO, but not in PRO. Plasma glucose Ra and Rd were substantially greater in PRO + HCHO vs. both PRO and PRO + LCHO ( P < 0.01). Whole body protein breakdown, synthesis, and oxidation rates, as well as whole body protein balance, did not differ between experiments. Mixed muscle protein FSR did not differ between treatments and averaged 0.10 ± 0.01, 0.10 ± 0.01, and 0.11 ± 0.01%/h in the PRO, PRO + LCHO, and PRO + HCHO experiments, respectively. In conclusion, coingestion of carbohydrate during recovery does not further stimulate postexercise muscle protein synthesis when ample protein is ingested.

scholarly journals Effect of dietary protein on energy metabolism including protein synthesis in the spiny lobster Sagmariasus verreauxi

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuangyao Wang ◽  
Chris G. Carter ◽  
Quinn P. Fitzgibbon ◽  
Basseer M. Codabaccus ◽  
Gregory G. Smith
Keyword(s):  
Protein Synthesis ◽  
Energy Metabolism ◽  
Dietary Protein ◽  
Spiny Lobster ◽  
Ammonia Excretion ◽  
Metabolic Energy ◽  
Whole Body ◽  
Body Protein ◽  
Energy Substrate ◽  
Sagmariasus Verreauxi

AbstractThis is the first study in an aquatic ectotherm to combine a stoichiometric bioenergetic approach with an endpoint stochastic model to explore dietary macronutrient content. The combination of measuring respiratory gas (O2 and CO2) exchange, nitrogenous (ammonia and urea) excretion, specific dynamic action (SDA), metabolic energy substrate use, and whole-body protein synthesis in spiny lobster, Sagmariasus verreauxi, was examined in relation to dietary protein. Three isoenergetic feeds were formulated with varying crude protein: 40%, 50% and 60%, corresponding to CP40, CP50 and CP60 treatments, respectively. Total CO2 and ammonia excretion, SDA magnitude and coefficient, and protein synthesis in the CP60 treatment were higher compared to the CP40 treatment. These differences demonstrate dietary protein influences post-prandial energy metabolism. Metabolic use of each major energy substrate varied at different post-prandial times, indicating suitable amounts of high-quality protein with major non-protein energy-yielding nutrients, lipid and carbohydrate, are critical for lobsters. The average contribution of protein oxidation was lowest in the CP50 treatment, suggesting mechanisms underlying the most efficient retention of dietary protein and suitable dietary inclusion. This study advances understanding of how deficient and surplus dietary protein affects energy metabolism and provides approaches for fine-scale feed evaluation to support sustainable aquaculture.

Effect of dietary protein on bed-rest-related changes in whole-body-protein synthesis

1990 ◽  
Vol 52 (3) ◽  
pp. 509-514 ◽  
Author(s):  
C A Stuart ◽  
R E Shangraw ◽  
E J Peters ◽  
R R Wolfe
Keyword(s):  
Protein Synthesis ◽  
Dietary Protein ◽  
Bed Rest ◽  
Whole Body ◽  
Body Protein

scholarly journals Comprehensive assessment of post-prandial protein handling by the application of intrinsically labelled protein in vivo in human subjects

2021 ◽  
pp. 1-9
Author(s):  
Jorn Trommelen ◽  
Andrew M. Holwerda ◽  
Philippe J. M. Pinckaers ◽  
Luc J. C. van Loon
Keyword(s):  
Protein Synthesis ◽  
Amino Acid ◽  
Stable Isotope ◽  
Dietary Protein ◽  
Protein Metabolism ◽  
Muscle Protein ◽  
Human Subjects ◽  
Whole Body ◽  
Body Protein

All human tissues are in a constant state of remodelling, regulated by the balance between tissue protein synthesis and breakdown rates. It has been well-established that protein ingestion stimulates skeletal muscle and whole-body protein synthesis. Stable isotope-labelled amino acid methodologies are commonly applied to assess the various aspects of protein metabolism in vivo in human subjects. However, to achieve a more comprehensive assessment of post-prandial protein handling in vivo in human subjects, intravenous stable isotope-labelled amino acid infusions can be combined with the ingestion of intrinsically labelled protein and the collection of blood and muscle tissue samples. The combined application of ingesting intrinsically labelled protein with continuous intravenous stable isotope-labelled amino acid infusion allows the simultaneous assessment of protein digestion and amino acid absorption kinetics (e.g. release of dietary protein-derived amino acids into the circulation), whole-body protein metabolism (whole-body protein synthesis, breakdown and oxidation rates and net protein balance) and skeletal muscle metabolism (muscle protein fractional synthesis rates and dietary protein-derived amino acid incorporation into muscle protein). The purpose of this review is to provide an overview of the various aspects of post-prandial protein handling and metabolism with a focus on insights obtained from studies that have applied intrinsically labelled protein under a variety of conditions in different populations.

Contribution of Skin to Whole-Body Protein Synthesis in Rats at Different Stages of Maturity

1992 ◽  
Vol 122 (11) ◽  
pp. 2167-2173 ◽  
Author(s):  
Christiane Obled ◽  
Maurice Arnal
Keyword(s):  
Protein Synthesis ◽  
Whole Body ◽  
Body Protein

Measurement of protein turnover in the small intestine of lambs. 2. Effects of feed intake

1997 ◽  
Vol 128 (2) ◽  
pp. 233-246 ◽  
Author(s):  
S. A. NEUTZE ◽  
J. M. GOODEN ◽  
V. H. ODDY
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Small Intestine ◽  
Experimental Model ◽  
Feed Intake ◽  
Protein Turnover ◽  
Jugular Vein ◽  
Specific Radioactivity ◽  
Whole Body ◽  
Body Protein

This study used an experimental model, described in a companion paper, to examine the effects of feed intake on protein turnover in the small intestine of lambs. Ten male castrate lambs (∼ 10 months old) were offered, via continuous feeders, either 400 (n = 5) or 1200 (n = 5) g/day lucerne chaff, and mean experimental liveweights were 28 and 33 kg respectively. All lambs were prepared with catheters in the cranial mesenteric vein (CMV), femoral artery (FA), jugular vein and abomasum, and a blood flow probe around the CMV. Cr-EDTA (0·139 mg Cr/ml, ∼ 0·2 ml/min) was infused abomasally for 24 h and L-[2,6-3H]phenylalanine (Phe) (420±9·35 μCi into the abomasum) and L-[U-14C]phenylalanine (49·6±3·59 μCi into the jugular vein) were also infused during the last 8 h. Blood from the CMV and FA was sampled during the isotope infusions. At the end of infusions, lambs were killed and tissue (n = 4) and digesta (n = 2) samples removed from the small intestine (SI) of each animal. Transfers of labelled and unlabelled Phe were measured between SI tissue, its lumen and blood, enabling both fractional and absolute rates of protein synthesis and gain to be estimated.Total SI mass increased significantly with feed intake (P < 0·05), although not on a liveweight basis. Fractional rates of protein gain in the SI tended to increase (P = 0·12) with feed intake; these rates were −16·2 (±13·7) and 23·3 (±15·2) % per day in lambs offered 400 and 1200 g/day respectively. Mean protein synthesis and fractional synthesis rates (FSR), calculated from the mean retention of 14C and 3H in SI tissue, were both positively affected by feed intake (0·01 < P < 0·05). The choice of free Phe pool for estimating precursor specific radioactivity (SRA) for protein synthesis had a major effect on FSR. Assuming that tissue free Phe SRA represented precursor SRA, mean FSR were 81 (±15) and 145 (±24) % per day in lambs offered 400 and 1200 g/day respectively. Corresponding estimates for free Phe SRA in the FA and CMV were 28 (±2·9) and 42 (±3·5) % per day on 400 g/day, and 61 (±2·9) and 94 (±6·0) on 1200 g/day. The correct value for protein synthesis was therefore in doubt, although indirect evidence suggested that blood SRA (either FA or CMV) may be closest to true precursor SRA. This evidence included (i) comparison with flooding dose estimates of FSR, (ii) comparison of 3H[ratio ]14C Phe SRA in free Phe pools with this ratio in SI protein, and (iii) the proportion of SI energy use associated with protein synthesis.Using the experimental model, the proportion of small intestinal protein synthesis exported was estimated as 0·13–0·27 (depending on the choice of precursor) and was unaffected by feed intake. The contribution of the small intestine to whole body protein synthesis tended to be higher in lambs offered 1200 g/day (0·21) than in those offered 400 g/day (0·13). The data obtained in this study suggested a role for the small intestine in modulating amino acid supply with changes in feed intake. At high intake (1200 g/day), the small intestine increases in mass and CMV uptake of amino acids is less than absorption from the lumen, while at low intake (400 g/day), this organ loses mass and CMV uptake of amino acids exceeds that absorbed. The implications of these findings are discussed.

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