337 Efficient RFI Bulls Presented Lower Fractional Synthesis Rates of Plasma Proteins When Fed Corn but Not Grass Based Diets

Abstract Protein turnover (PT), the continual synthesis and degradation of body proteins not leading to protein gain, is an essential high energy-demanding process. We assumed that PT might explain the between-animal variations of residual feed intake (RFI). The objective was to measure PT in extreme RFI cattle fed two contrasted diets (grass or corn-based). We conducted a RFI test for 84 days with 100 Charolais bulls and we selected the 32 most extreme (8 per diet and RFI group) for PT measurements using 1) the urinary 3-methyl-histidine to creatinine ratio, as a biomarker of the fractional protein degradation rate (FDR) of skeletal-muscle and 2) the isotopic N turnover rate measured in urine and plasma, as a proxy, respectively, of the whole-body FDR and the fractional protein synthesis rates (FSR) of plasma proteins. The 3-methyl-histidine and creatinine were determined from 10 d total urine collection. Isotopic N turnover in urine and plasma was evaluated by modelling the 15N depletion rate over 112 d following an isotopic N dietary change. Higher plasma FSR and higher skeletal-muscle and whole-body FDR were observed with corn-vs-grass diets (≥11%; P ≤ 0.03), in line with higher metabolizable protein and net energy intakes (≥10%, P = 0.001). Differences between extreme RFI animals were noted with the corn diets only, where efficient animals presented significant lower plasma FSR (-10%; P = 0.04) and numerically lower skeletal-muscle and whole-body FDR (-13% and - 8.9%; P > 0.16 respectively) than non-efficient. Non-significant differences were probably due to an insufficient size of our experimental setup. Plasma FSR is related to the PS of hepatic exportation, hence the lower plasma FSR observed in efficient RFI animals fed corn diets may reflect a lower organs to carcass ratio. Altogether results suggests that efficient RFI bulls fed corn diets had a lower hepatic PT with no-significant changes of whole-body and skeletal muscle PT.

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The isotopic N turnover rate as a proxy to evaluate in the long-term the protein turnover in growing ruminants

10.1101/543116 ◽

2019 ◽

Author(s):

Gonzalo Cantalapiedra-Hijar ◽

Hélène Fouillet ◽

Céline Chantelauze ◽

Nadezda Khodorova ◽

Lahlou Bahloul ◽

...

Keyword(s):

Protein Turnover ◽

Plasma Proteins ◽

Farm Animals ◽

Whole Body ◽

Synthesis Rate ◽

Non Invasive ◽

Depletion Rate ◽

Fractional Synthesis ◽

Large Farm

ABSTRACTProtein turnover is an energy-consuming process essential for ensuring the maintenance of living organisms. Gold standard methods for protein turnover measurement are based on intravenous infusions of stable isotopes. Although accurate they have inherent drawbacks precluding their generalization for large farm animals and during long time periods. We proposed here a non-invasive proxy of the whole-body fractional protein degradation (WBFPDR; protein turnover for a growing animal) in the long term and in a large number of beef cattle. The proxy is based on the rate at which urine-N and plasma proteins are progressively depleted in 15N after a slight decrease in the isotopic N composition of diet (i.e. diet-switch). We aimed to test the ability of this proxy to adequately discriminate the WBFPDR of 36 growing-fattening young bulls assigned to different dietary treatments known to impact the protein turnover rate: the protein content and amino acid profile. To achieve this objective, the experimental diets were enriched with 15N labeled-urea during 35 days while the animals were adapted to diets. After stopping the 15N labeled-urea administration the animals were thereafter sampled for spot urines (n = 13) and blood (n = 10) over 5 months and analyzed for their 15N enrichments in total N and plasma proteins, respectively. Adequately fitting the 15N kinetics in plasma proteins and urines required mono- and bi-exponential models, respectively, and the model parameters were compared across dietary conditions using a non-linear mixed effect model. The single 15N depletion rate found in plasma proteins represented their fractional synthesis rate, whereas the slowest depletion rate found in urines was interpreted as a proxy of the WBFPDR. The proxy here tested in urines suggested different WBFPDR values between Normal vs High protein diets but not between balanced vs unbalanced methionine diets. In contrast, the proxy tested in plasma indicated that both dietary conditions affected the fractional synthesis rate of plasma proteins. We consider that the rate at which urines are progressively 15N-depleted following an isotopic diet-switch could be proposed as a non-invasive proxy of the long-term whole-body fractional protein degradation rate for large farm animals.

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The effects of breed and level of nutrition on whole-body and muscle protein metabolism in pure-bred Aberdeen Angus and Charolais beef steers

British Journal Of Nutrition ◽

10.1017/s0007114500001550 ◽

2000 ◽

Vol 84 (3) ◽

pp. 275-284 ◽

Cited By ~ 18

Author(s):

G. E. Lobley ◽

K. D. Sinclair ◽

C. M. Grant ◽

L. Miller ◽

D. Mantle ◽

...

Keyword(s):

Skeletal Muscle ◽

Protein Metabolism ◽

Muscle Protein ◽

Live Weight ◽

Whole Body ◽

Synthesis Rate ◽

Eating Quality ◽

Eye Muscle ◽

Fractional Synthesis Rate ◽

Fractional Synthesis

Eighteen pure-bred steers (live weight 350 kg) from each of two breeds, Aberdeen Angus (AA) and Charolais (CH), were split into three equal groups (six animals each) and offered three planes of nutrition during a 20-week period. The same ration formulation was offered to all animals with amounts adjusted at 3-week intervals to give predicted average weight gains of either 1·0 kg/d (M/M group) or 1·4 kg/d (H/H group). The remaining group (M/H) were offered the same amount of ration as the M/M group until 10 weeks before slaughter when the ration was increased to H. Data on animal performance, carcass characteristics and fibre-type composition in skeletal muscle are presented elsewhere (; ). On three occasions (17, 10 and 2 weeks before slaughter) the animals were transferred to metabolism stalls for 1 week, during which total urine collection for quantification of Nτ-methylhistidine (Nτ-MeH) elimination was performed for 4 d. On the last day, animals were infused for 11 h with [2H5] phenylalanine with frequent blood sampling (to allow determination of whole-body phenylalanine flux) followed by biopsies from m. longissimus lumborum and m. vastus lateralis to determine the fractional synthesis rate of mixed muscle protein. For both breeds, the absolute amount of Nτ-MeH eliminated increased with animal age or weight (P < 0·001) and was significantly greater for CH steers, at all intake comparisons, than for AA (P < 0·001). Estimates of fractional muscle breakdown rate (FBR; calculated from Nτ-MeH elimination and based on skeletal muscle as a fixed fraction of live weight) showed an age (or weight) decline for M/M and H/H groups of both breeds (P < 0·001). FBR was greater for the H/H group (P = 0·044). The M/H group also showed a lower FBR for the first two measurement periods (both at M intake) but increased when intake was raised to H. When allowance was made for differences in lean content (calculated from fat scores and eye muscle area in carcasses at the end of period 3), there were significant differences in muscle FBR with intake (P = 0·012) but not between breed. Whole-body protein flux (WBPF; g/d) based on plasma phenylalanine kinetics increased with age or weight (P < 0·001) and was similar between breeds. The WBPF was lower for M/M compared with H/H (P < 0·001) based on either total or per kg live weight0·75. Muscle protein fractional synthesis rate (FSR) declined with age for both breeds and tended to be higher at H/H compared with M intakes (intake × period effects, P < 0·05). Changing intake from M to H caused a significant increase (P < 0·001) in FSR. The FSR values for AA were significantly greater than for CH at comparable ages (P = 0·044). Although FSR and FBR responded to nutrition, these changes in protein metabolism were not reflected in differences in meat eating quality (Sinclair et al. 2000).

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The isotopic nitrogen turnover rate as a proxy to evaluate in the long-term the protein turnover in growing ruminants

The Journal of Agricultural Science ◽

10.1017/s0021859620000118 ◽

2019 ◽

Vol 157 (9-10) ◽

pp. 701-710

Author(s):

Gonzalo Cantalapiedra-Hijar ◽

Hélène Fouillet ◽

Céline Chantelauze ◽

Nadezda Khodorova ◽

Lahlou Bahloul ◽

...

Keyword(s):

Protein Turnover ◽

Plasma Proteins ◽

Farm Animals ◽

Synthesis Rate ◽

Fractional Synthesis Rate ◽

Non Invasive ◽

Depletion Rate ◽

Fractional Synthesis ◽

Large Farm ◽

Diet Switch

AbstractProtein turnover is an energy-consuming process that is essential for ensuring the maintenance of living organisms. Gold standard methods for whole-body protein turnover (WBPT) measurement have inherent drawbacks precluding their generalization for large farm animals and use during long periods. Here, we proposed a non-invasive proxy for the WBPT over a long period of time and in a large number of beef cattle. The proxy is based on the rate at which urine-N and plasma proteins are progressively depleted in terms of 15N after a slight decrease in the isotopic N composition of the diet (i.e. diet switch). We aimed to test the ability of this proxy to adequately discriminate the WBPT of 36 growing-fattening young bulls assigned to different dietary treatments known to impact the WBPT rate, with different protein contents (normal v. high) and amino acid profiles (balanced v. unbalanced in methionine). The 15N depletion rate found in plasma proteins represented their fractional synthesis rate, whereas the slow depletion rate found in urine was interpreted as a proxy of the WBPT. The proxy tested in urine suggested different WBPT values between the normal- and high-protein diets but not between the balanced and unbalanced methionine diets. In contrast, the proxy tested in plasma indicated that both dietary conditions affected the fractional synthesis rate of plasma proteins. We considered that the rate at which urine is progressively 15N-depleted following an isotopic diet switch could be proposed as a non-invasive proxy of the WBPT rate in large farm animals.

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Carbohydrate ingestion augments l-carnitine retention in humans

Journal of Applied Physiology ◽

10.1152/japplphysiol.01011.2006 ◽

2007 ◽

Vol 102 (3) ◽

pp. 1065-1070 ◽

Cited By ~ 31

Author(s):

Francis B. Stephens ◽

Claire E. Evans ◽

Dumitru Constantin-Teodosiu ◽

Paul L. Greenhaff

Keyword(s):

Skeletal Muscle ◽

Serum Insulin ◽

Area Under The Curve ◽

Whole Body ◽

Lower Plasma ◽

Carbohydrate Ingestion ◽

Glucose Syrup ◽

Flavored Water ◽

The Difference ◽

Total Carnitine

Maintaining hyperinsulinemia (∼150 mU/l) during steady-state hypercarnitinemia (∼550 μmol/l) increases skeletal muscle total carnitine (TC) content by ∼15% within 5 h. The present study aimed to investigate whether an increase in whole body carnitine retention can be achieved through l-carnitine feeding in conjunction with a dietary-induced elevation in circulating insulin. On two randomized visits ( study A), eight men ingested 3 g/day l-carnitine followed by 4 × 500-ml solutions, each containing flavored water (Con) or 94 g simple sugars (glucose syrup; CHO). In addition, 14 men ingested 3 g/day l-carnitine followed by 2 × 500 ml of either Con or CHO for 2 wk ( study B). Carbohydrate ingestion in study A resulted in a fourfold greater serum insulin area under the curve when compared with Con ( P < 0.001) and in a lower plasma TC concentration throughout the CHO visit ( P < 0.05). Twenty-four-hour urinary TC excretion in the CHO visit was lower than in the Con visit in study A (155.0 ± 10.7 vs. 212.1 ± 17.2 mg; P < 0.05). In study B, daily urinary TC excretion increased after 3 days (65.9 ± 18.0 to 281.0 ± 35.0 mg; P < 0.001) and remained elevated throughout the Con trial. During the CHO trial, daily urinary TC excretion increased from a similar basal value of 53.8 ± 9.2 to 166.8 ± 17.3 mg after 3 days ( P < 0.01), which was less than during the Con trial ( P < 0.01), and it remained lower over the course of the study (P < 0.001). The difference in plasma TC concentration in study A and 24-h urinary TC excretion in both studies suggests that insulin augmented the retention of carnitine in the CHO trials.

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Regional Sympathetic Nervous Activation after a Large Meal in Humans

Clinical Science ◽

10.1042/cs0890145 ◽

1995 ◽

Vol 89 (2) ◽

pp. 145-154 ◽

Cited By ~ 62

Author(s):

Helen S. Cox ◽

David M. Kaye ◽

Jane M. Thompson ◽

Andrea G. Turner ◽

Garry L. Jennings ◽

...

Keyword(s):

Skeletal Muscle ◽

Oxygen Consumption ◽

Sympathetic Nerve ◽

Muscle Sympathetic Nerve Activity ◽

Nervous Activity ◽

High Energy ◽

Whole Body ◽

Sympathetic Nervous Activity ◽

Sympathetic Nervous ◽

Large Meal

1. To investigate the link between post-prandial thermogenesis and sympathetic nervous activation we have studied the effects of a single large meal on regional sympathetic nervous activity in healthy, lean subjects. 2. In nine male subjects, noradrenaline spillover was measured from the heart, kidney and liver using isotope dilution, both while fasting and after consumption of a high-energy liquid meal of composition 53% carbohydrate, 32% fat and 15% protein (energy value 2.64–3.51 MJ). Regional oxygen consumption, whole-body oxygen consumption and, in a subset of subjects, muscle sympathetic nerve firing (microneurography) were also measured. 3. Both whole-body oxygen consumption (P < 0.03) and total body spillover of noradrenaline (P < 0.01) rose after the meal, with peak increases of 24% and 56% respectively. Spillover of noradrenaline from the heart was unchanged, that from the hepatosplanchnic circulation increased marginally (0.377 nmol/min to 0.480 nmol/min, P = 0.09), while renal noradrenaline spillover more than doubled (0.440 nmol/min to 0.937 nmol/min, P < 0.05). Skeletal muscle sympathetic nerve activity (peroneal nerve) increased from 7.7 bursts/min at rest to peak at 17.9 bursts/min 60 min after the meal in the three subjects in whom stable recordings were obtained. 4. The meal increased oxygen consumption in the kidneys and liver significantly, from 11.5 ± 1.6 ml/min to 14.5 ± 1.1 ml/min and from 46 ± 7 ml/min to 57 ± 6 ml/min respectively (P < 0.05), but not in the heart. 5. Consumption of a large meal produces a substantial and relatively selective increase in sympathetic outflow to the kidneys and skeletal muscle. While resting regional oxygen consumptions and noradrenaline spillovers were related, the changes that occurred in each were unrelated, so that no direct relationship could be demonstrated between post-prandial thermogenesis and sympathetic activity.

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Neural control of glucose uptake by skeletal muscle after central administration of NMDA

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1995.268.2.r492 ◽

1995 ◽

Vol 268 (2) ◽

pp. R492-R497 ◽

Cited By ~ 1

Author(s):

C. H. Lang ◽

M. Ajmal ◽

A. G. Baillie

Keyword(s):

Skeletal Muscle ◽

Blood Flow ◽

Glucose Uptake ◽

Neural Control ◽

Plasma Insulin ◽

Regional Blood Flow ◽

Muscle Blood Flow ◽

Whole Body ◽

Glucose Disposal ◽

Central Administration

Intracerebroventricular injection of N-methyl-D-aspartate (NMDA) produces hyperglycemia and increases whole body glucose uptake. The purpose of the present study was to determine in rats which tissues are responsible for the elevated rate of glucose disposal. NMDA was injected intracerebroventricularly, and the glucose metabolic rate (Rg) was determined for individual tissues 20-60 min later using 2-deoxy-D-[U-14C]glucose. NMDA decreased Rg in skin, ileum, lung, and liver (30-35%) compared with time-matched control animals. In contrast, Rg in skeletal muscle and heart was increased 150-160%. This increased Rg was not due to an elevation in plasma insulin concentrations. In subsequent studies, the sciatic nerve in one leg was cut 4 h before injection of NMDA. NMDA increased Rg in the gastrocnemius (149%) and soleus (220%) in the innervated leg. However, Rg was not increased after NMDA in contralateral muscles from the denervated limb. Data from a third series of experiments indicated that the NMDA-induced increase in Rg by innervated muscle and its abolition in the denervated muscle were not due to changes in muscle blood flow. The results of the present study indicate that 1) central administration of NMDA increases whole body glucose uptake by preferentially stimulating glucose uptake by skeletal muscle, and 2) the enhanced glucose uptake by muscle is neurally mediated and independent of changes in either the plasma insulin concentration or regional blood flow.

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Association between hand muscle thickness and whole-body skeletal muscle mass in healthy adults: a pilot study

Journal of Physical Therapy Science ◽

10.1589/jpts.29.1644 ◽

2017 ◽

Vol 29 (9) ◽

pp. 1644-1648 ◽

Cited By ~ 6

Author(s):

Akio Morimoto ◽

Tadashi Suga ◽

Nobuaki Tottori ◽

Michio Wachi ◽

Jun Misaki ◽

...

Keyword(s):

Skeletal Muscle ◽

Pilot Study ◽

Muscle Mass ◽

Skeletal Muscle Mass ◽

Muscle Thickness ◽

Healthy Adults ◽

Whole Body ◽

Hand Muscle

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Slow skeletal muscle myosin-binding protein-C (MyBPC1) mediates recruitment of muscle-type creatine kinase (CK) to myosin

Biochemical Journal ◽

10.1042/bj20102007 ◽

2011 ◽

Vol 436 (2) ◽

pp. 437-445 ◽

Cited By ~ 31

Author(s):

Zhe Chen ◽

Tong-Jin Zhao ◽

Jie Li ◽

Yan-Song Gao ◽

Fan-Guo Meng ◽

...

Keyword(s):

Skeletal Muscle ◽

Creatine Kinase ◽

Muscle Contraction ◽

Binding Protein ◽

High Energy ◽

Functional Coupling ◽

Muscle Type ◽

Myosin Binding Protein ◽

Slow Skeletal Muscle ◽

Myosin Binding

Muscle contraction requires high energy fluxes, which are supplied by MM-CK (muscle-type creatine kinase) which couples to the myofibril. However, little is known about the detailed molecular mechanisms of how MM-CK participates in and is regulated during muscle contraction. In the present study, MM-CK is found to physically interact with the slow skeletal muscle-type MyBPC1 (myosin-binding protein C1). The interaction between MyBPC1 and MM-CK depended on the creatine concentration in a dose-dependent manner, but not on ATP, ADP or phosphocreatine. The MyBPC1–CK interaction favoured acidic conditions, and the two molecules dissociated at above pH 7.5. Domain-mapping experiments indicated that MM-CK binds to the C-terminal domains of MyBPC1, which is also the binding site of myosin. The functional coupling of myosin, MyBPC1 and MM-CK is further corroborated using an ATPase activity assay in which ATP expenditure accelerates upon the association of the three proteins, and the apparent Km value of myosin is therefore reduced. The results of the present study suggest that MyBPC1 acts as an adaptor to connect the ATP consumer (myosin) and the regenerator (MM-CK) for efficient energy metabolism and homoeostasis.

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