• Title, Summary, Keyword: fractional synthesis rate

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Inhibition of Corticosterone-induced Muscle Protein Synthesis by the Anabolic Steroid Nandrolone Phenylpropionate in Female Rats (아나보릭스테로이드인 Nandrolone Phenylpropionate가 암컷 쥐에서 코티코스테론에 의해 야기된 근육단백질 쇠퇴와 근육단백질 합성율 감소에 미치는 영향)

  • 주종재
    • Journal of Nutrition and Health
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    • v.29 no.8
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    • pp.867-873
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    • 1996
  • This study was undertaken to determine whether the anabolic steroid nandrolone phenylpropionate(NPP) can inhibit the muscle atrophy and reduction in muscle protein synthesis caused by glucocorticoids in female rates. Daily injections of 50mg/kg of corticosterone for eight days induced significant reductions in body weight gain and protein without affecting food intake. The mass, protein and RNA content, ratio of RNA to protein, and fractional rate of protein synthesis, measured in vivo, of gastrocnemius muscle were all significantly reduced by corticosterone treatement. Simultaneous administration of NPP at a dose of 10mg/kg with corticosteorne (50mg/kg) fully inhibited the reductions in the mass, protein and RNA content of gastrocnemius muscle, and body weight gain and protein with no alteration in food intake but the reduction in fractional rate of muscle protein syntheis was only partially prevented. The results indicate that the anabolic steroid nandrolone phenylpropionate is capable of preventing muscle atrophy in female rats treated with excess corticosterion.

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Measurement of Age-Related Changes in Bone Matrix Using 2H2O Labeling

  • Lee, Jeong-Ae;Kim, Yoo-Kyeong
    • Preventive Nutrition and Food Science
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    • v.10 no.1
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    • pp.40-45
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    • 2005
  • Age-related changes in bone metabolism are well established by biochemical markers of bone matrix in serum and urine, but analysis of the residual bone matrix, which is still turning over, has not been investigated. In the present study, we measured in vivo rates of bone protein synthesis using a precursor-product method based on the exchange of ²H from ²H₂O into amino acids. Four percent ²H₂O was administered to mice in drinking water after intraperitonial (i.p) bolus injection of 99.9% ²H₂O. Mice were divided into the two groups: growing young mice were administered 4% ²H₂O for 12 weeks after an i.p bolus injection at 5 week of age, whereas weight stable adult mice started drinking 4% ²H₂O 8 weeks later than the growing group and continued 4% ²H₂O drinking for 8 weeks. Mass isotopomer abundance in alanine from bone protein was analyzed by gas chromatography/mass spectrometry. Body ²H₂O enrichments were in the range of 1.88-2.41% over the labeling period. The fractional synthesis rates (ks) of bone protein were 2.000±0.071%/d for growing mice and 0.243±0.014%/d for adult mice. These results demonstrate that the bone protein synthesis rate decreases with age and present direct evidence of age-related changes in bone protein synthesis.

The Effects of Dietary Lysine Deficiency on Muscle Protein Turnover in Postweanling Pigs

  • Chang, Yi-Ming;Wei, Hen-Wei
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.9
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    • pp.1326-1335
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    • 2005
  • The main purpose of this study is to investigate the effects of dietary lysine deficiency on protein turnover of porcine muscles. There were 18 LYD three-breed-crossing postweanling barrows from six litters cannulated with gastric tubes through the esophagus at approximate 10 kg of body weight and allocated into three treatment groups. When their body weights reached over 12 kg, one group was sacrificed for determining the initial protein masses of m. masseter, m. longissimus dorsi, m. adductor and m. biceps femoris from the right body side. The others received a diet containing 100% or 61.4% (calculated values) of the lysine requirement (NRC, 1998) multiplied by 1.103 for a period of 17 days. Daily feed provision was computed for each pig according to body weight at the same day. All pigs were infused a flooding dose of $^2$H$_5$-phenylalanine to determine the fractional protein synthesis rates (FSR) of the aforementioned muscles in the end. Their four muscles from the right body side were also dissected for measuring the fractional rates of protein accretion (FAR). As for protein degradation, fractional rates (FDR) were calculated by differences between synthesis and accretion. Results showed that the lysine deficiency resulted in, significantly (p<0.05), lighter body weights, smaller muscles and a slower growth rate. The protein mass, accreted by the muscles, of the deficient group was only 54% averaged of the pigs fed adequately (p<0.05). The FAR of these muscles in the deficient group was significantly lower (p<0.05) and only achieved 61.1% averaged of the control; there was no significant difference (p>0.05), nevertheless, in the amino-acid composition of muscles between two groups. The lysine deficiency reduced significantly (p<0.05) the FSR of m. longissimus dorsi but did not influence its FDR. The m. biceps femoris also presented an inhibited FSR while its FDR reduced only exhibited a very high tendency (p = 0.055) compared to the adequately-fed pigs. As for the m. masseter and m. adductor, both of the FSR and FDR were depressed significantly (p<0.05) by the lysine deficiency, and changes in the FSR were severer than those in the FDR, so that their FAR were significantly slower (p<0.05) in comparison with the control group. The lysine deficiency also inhibited the RNA translation activity of the muscles while the effects on RNA capacity were not significant (p>0.05). In conclusion, the FAR of muscle protein was changed by the current lysine deficiency through the alterations in the FSR and/or FDR.

Short-term protein intake increases fractional synthesis rate of muscle protein in the elderly: meta-analysis

  • Gweon, Hyun-Soo;Sung, Hee-Ja;Lee, Dae-Hee
    • Nutrition Research and Practice
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    • v.4 no.5
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    • pp.375-382
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    • 2010
  • The precise effects of protein intake on fractional synthesis rate (FSR) of muscle protein are still under debate. The sample size of these studies was small and the conclusions in young and elderly subjects were inconsistent. To assess the effect of dietary protein intake on the FSR level, we conducted a meta-analysis of controlled protein intake trials. Random-effects models were used to calculate the weighted mean differences (WMDs). Ten studies were included and effects of short-term protein intake were evaluated. In an overall pooled estimate, protein intake significantly increased the FSR (20 trials, 368 participants; WMD: 0.025%/h; 95%CI: 0.019-0.031; P < 0.0001). Meta-regression analysis suggested that the protein dose was positively related to the effect size (regression coefficient = 0.108%/h; 95%CI: 0.035, 0.182; P = 0.009). A subgroup analysis indicated that protein intake significantly increased FSR when the protein dose was ${\leq}$ 0.80 g/kg BW (16 trials, 308 participants; WMD: 0.027%/h; 95%CI: 0.019-0.031; P < 0.0001), but did not affect FSR when the protein dose was > 0.80 g/kg BW (4 trials, 60 participants; WMD: 0.016%/h; 95%CI: 0.004-0.029; P = 0.98). In conclusion, this study is the first integrated results showing that a short-term protein intake is effective at improving the FSR of muscle protein in the healthy elderly as well as young subjects. This beneficial effect seems to be dose-dependent when the dose levels of protein range from 0.08 to 0.80 g/kg BW.

Effects of the Anabolic Steroid, Nandrolone Pheylpropionate, on Growth and Muscle Protein Metabolism in ACTH-treated Rats (ACTH를 투여한 흰쥐에서 아나보릭스테로이드인 Nandrolone Phenylpropionate가 성장한 근육단백질 대사에 미치는 영향)

  • 주종재
    • Journal of Nutrition and Health
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    • v.29 no.8
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    • pp.874-880
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    • 1996
  • The effects of an anabolic steroid, nandrolone phenylpropionate(NPP), on body weight gain and body protein, and muscle protein metabolism were inestigated in adrenocorticotrophic hormone(ACTH)-treated male and female rats. Daily injections of 100ug/day of ACTH for 7-8 days caused a cessation of growth in females and a net loss of body weight in males which were associated with significant reductions in body protein content. However, food intake was not affected by ACTH in either sex. The weight, protein content and fractional rate of protein synthesis, measured in vivo, of gastrocnemius muscle were all significantly reduced in both sexes. NPP at a dose of 4mg/kg body weight prevented the reduction in body weight gain in ACTH-treate females but not in males. However, boy protein content was increased by NPP in both sexes which was associated with increases in the weight, protein content and fractional rate of protein synthesis of gastrocnemius muscle. ACTH treatment caused a marked increase in plasma concentrations of corticosterone in both sexes. NPP suppressed much of the increases in corticosterone concentrations in both sexes. The results of the present study suggest that NPP exerts at least part of its anabolic effect by reducing plasma concentrations of catabolic glucocorticoid hormones, through suppressing the response of the adrenals to ACTH.

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Response of Muscle Protein Synthesis to the Infusion of Insulin-like Growth Factor-I and Fasting in Young Chickens

  • Kita, K.;Shibata, T.;Aman Yaman, M.;Nagao, K.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.12
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    • pp.1760-1764
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    • 2002
  • In order to elucidate the physiological function of circulating IGF-I on muscle protein synthesis in the chicken under malnutritional conditions, we administrated recombinant chicken IGF-I using a osmotic mini pump to fasted young chickens and measured the rate of muscle protein synthesis and plasma metabolite. The pumps delivered IGF-I at the rate of $22{\mu}g/d\{300{\mu}g{\cdot}(kg\;body\;weight{\cdot}d)^{-1}\}$. Fractional rate of protein synthesis in the muscle was measured using a large dose injection of L-[$2,6-^3H$]phenylalanine. Constant infusion of chicken IGF-I did not affect plasma glucose level. Significant interaction between dietary treatment and IGF-I infusion was observed in plasma NEFA and total cholesterol concentrations. When chicks were fasted, IGF-I infusion decreased plasma NEFA and total cholesterol concentrations. On the other hand, IGF-I administration did not affect plasma levels of both metabolites. Fasting reduced plasma triglyceride concentration significantly. IGF-I infusion also decreased the level of plasma triglyceride. Plasma IGF-I concentration of young chickens was halved by fasting for 1 d. IGF-I infusion using an osmotic minipump for 1 d increased plasma IGF-I concentration in fasted chicks to the level of fed chicks. Fasting decreased body weight and the loss of body weight was significantly ameliorated by IGF-I infusion. There was a significant interaction between dietary treatment and IGF-I infusion in the fractional rate of breast muscle protein synthesis. There was no effect of IGF-I infusion on muscle protein synthesis in fed chicks. Muscle protein synthesis reduced by fasting was ameliorated by IGF-I infusion, but did not reach to the level of fed control. Muscle weight of fasted chicks infused with IGF-I was similar to fasted birds without IGF-I infusion, which suggests that muscle protein degradation would be increased by IGF-I infusion as well as protein synthesis in fasted chicks.

Thermal Characteristics of LaMnO3 Non-isothermal Synthesis Reaction (LaMnO3 비등온 합성반응의 열적특성)

  • Jeon, Jong Seol;Lee, Jung Hun;Yoon, Chang Hyeok;Yoo, Dong Jun;Lim, Dae Ho;Kang, Yong
    • Korean Chemical Engineering Research
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    • v.54 no.3
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    • pp.404-409
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    • 2016
  • Thermal Characteristics and kinetic parameters of $LaMnO_3$ synthesis reaction were investigated by means of TGA (Thermogravimetric analysis) at non-isothermal heating conditions (5.0, 10.0, 15.0 and 20.0 K/min). The reaction was occurred rapidly at 450~600K (X=0.4~0.7) depending on the heating rate. Activation energy for the synthesis of $LaMnO_3$ from the precursor, which was determined by different method such as Friedman, Ozawa-Flynn-Wall and Vyazovkin methods, was in the range of 23~243 kJ/g-mol depending on the fractional conversion level and estimation method. The reaction order decreased with increasing heating rate and fractional conversional level. The average reaction order was 4.50 in case of X=0.1~0.3, while it was 1.87 in case of X=0.7~0.9, respectively. The value of frequency factor of reaction rate increased with inceasing heating rate and fractional conversion level. The aveage value of frequency factor was 205.6 ($min^{-1}$) when X=0.1~0.3, while it was 475.2 ($min^{-1}$) when X=0.7~0.9, respectively.

MUSCLE PROTEIN SYNTHESIS IN VITRO IN CHICKS FED A LOW-PROTEIN DIET

  • Kita, K.;Kuzuya, Y.;Matsunami, S.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.9 no.2
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    • pp.171-174
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    • 1996
  • Muscle protein synthesis in vitro was measured in chicks fed low-protein(10% CP) and control(20% CP) diets. Right leg muscles (M. gastrocnemius) were mounted on a support made of stainless steel to stretch in constant tension, whereas left leg muscles were unmounted. Both leg muscles were incubated in Dulbecco's modified Eagle's medium including L-[$4-^3H$] phenylalanine for 60 min to measure in vitro protein synthesis. There was no significant difference in fractional synthesis rate(FSR) of muscle protein between both dietary protein levels, whereas FSR with stretch in constant tension was significantly higher than that without constant tension due to an increase in the absolute synthesis rate(ASR) per unit RNA(the efficiency of RNA to synthesize protein). The ASR of muscle protein in chicks fed the control diet was significantly higher than that in the low-protein diet group.

EFFECT OF CIMATEROL ON GROWTH AND 3-METHYLHISTIDINE EXCRETION IN RATS

  • Kim, Y.S.;Lee, Y.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.3 no.4
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    • pp.313-318
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    • 1990
  • Forty-two outbred female Sprague-Dawley rats weighing 145 g were used to study the effects of a beta-agonist, cimaterol, on growth, body composition and urinary excretion of 3-methylhistidine (MH) at 3, 6 and 18 d. Cimaterol (CIM) was administered in the feed at 10 mg/kg. The growth promoting effect of CIM was most evident during the initial part of the feeding period, followed by a gradual decrease in the magnitude of the response with no significant effect at 18 d. The action of CIM was confined to skeletal and cardiac muscles with no stimulating effect on other organs. The amount of urine excretion and urinary MH excretion was reduced (p<.01) at 3 d in the CIM group. No difference was found at 6 d, followed by an increased urine excretion (p<.05) and MH excretion (p<.01) at 18 d. An inverse relationship between growth rate and urinary MH excretion suggested that the increased growth rate of CIM-fed rats during the initial part of the feeding period is primarily attributed to the decreased protein degradation rate. It was further suggested that both fractional synthesis rate and fractional degradation rate increased during the later part of the feeding period.

DIETARY MEDIUM CHAIN TRIGLYCERIDE INCREASE LIVER PROTEIN SYNTHESIS IN CHICKS

  • Kita, Kazumi;Mabayo, R.T.;Furuse, M.;Okumura, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.3
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    • pp.339-342
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    • 1993
  • This influence of dietary medium chain triglyceride on liver protein synthesis in chicks was investigated using a large dose injection of $L-[4-^3H]$ phenylalanine. Dietary medium chain triglyceride increased liver weight and liver fat content of chicks compared to the long chain triglyceride group. Fractional synthesis rate of liver protein was increased by dietary medium chain triglyceride, which was accounted for not by elevating protein synthesized per unit RNA but by enhancing RNA: protein ratio.