The Effects of Low-Protein Diet and Uraemia upon Urea-Cycle Enzymes and Transaminases in Rats

1972 ◽  
Vol 43 (3) ◽  
pp. 371-376 ◽  
Author(s):  
C. L. Brown ◽  
B. J. Houghton ◽  
R. L. Souhami ◽  
P. Richards
Keyword(s):  
Protein Intake ◽  
Urea Cycle ◽  
Essential Amino Acids ◽  
Normal Diet ◽  
Protein Restriction ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Low Protein ◽  
Branched Chain Amino Acid ◽  
Branched Chain

1. Activities of arginine synthetase system enzymes, alanine aminotransferase (AlT) and branched-chain amino acid transaminase (BATase) were measured in control and uraemic rats after 2 weeks on a free protein intake and after 10 days on a low-protein diet. 2. Protein restriction alone reduced the activity of all three enzymes. 3. Uraemia alone increased the activity of arginine synthetase system enzymes and AlT. BATase was not altered. 4. After protein restriction the BATase activity in uraemic rats decreased to the same extent as in controls. The activity of arginine synthetase system enzymes and AlT were significantly higher than in protein-restricted controls and were the same as in control rats on a normal diet. 5. Practical consequences of the finding that uraemia prevented the decrease of AlT but not of BATase activity in response to a low-protein diet are discussed, with particular reference to reutilization of urea-nitrogen for the synthesis of non-essential and essential amino acids.

Effect of High-Salt, High-Carbohydrate, Low-Protein Diet on Hypertension in the Rat

1973 ◽  
Vol 45 (s1) ◽  
pp. 99s-102s
Author(s):  
Hideo Ueda
Keyword(s):  
Blood Pressure ◽  
High Protein Diet ◽  
Normal Diet ◽  
High Salt ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Heart Weight ◽  
Hypertensive Rats ◽  
High Carbohydrate ◽  
Low Protein

1. High-salt, high-carbohydrate and low-protein diet induces remarkable elevation of blood pressure in spontaneous hypertensive rats (SHR). 2. These animals have low serum potassium, low blood urea nitrogen and high blood sugar. 3. Heart weight is increased in proportion to the elevation of blood pressure. 4. Kidney weight of rats receiving the high-salt, high-carbohydrate and low-protein diet was, by contrast, smaller than SHR receiving a normal diet. 5. The kidneys of SHR receiving a high-salt, high-protein diet were twice as heavy as the kidneys of normal rats. 6. Similar dietary modifications in Goldblatt hypertensive rats to those in SHR produced similar changes in blood pressure and heart weight.

scholarly journals Survival on dialysis among chronic renal failure patients treated with a supplemented low-protein diet before dialysis.

1995 ◽  
Vol 6 (5) ◽  
pp. 1379-1385
Author(s):  
J Coresh ◽  
M Walser ◽  
S Hill
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Mortality Rate ◽  
Serum Creatinine ◽  
Dietary Treatment ◽  
Mortality Rates ◽  
Protein Restriction ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Low Protein

Concerns have been raised about the possibility of protein restriction resulting in malnutrition and poor subsequent survival on dialysis. However, no studies have examined patients treated with protein restriction to determine their subsequent survival on dialysis. This study prospectively monitored 67 patients with established chronic renal failure (mean initial serum creatinine of 4.3 mg/dL) who were treated with a very low-protein diet (0.3 g/kg per day) supplemented with either essential amino acids or a ketoacid-amino acid mixture and observed closely for clinical complications. Forty-four patients required dialysis. Once dialysis was started, dietary treatment was no longer prescribed. The cumulative mortality rate during the first 2 yr after starting dialysis was 7% (95% confidence interval, 0 to 16%). During this period, only two deaths occurred compared with 11.5 deaths expected on the basis of national mortality rates adjusted for age, sex, race, and cause of renal disease (P = 0.002). However, the protective effect was limited to the first 2 yr on dialysis. Thereafter, mortality rates increased, resulting in a total of 10 deaths during 96.4 person-years of follow-up, which was not significantly lower than the 14.9 deaths expected (P = 0.25). Extrapolation of sequential serum creatinine measurements made before dietary treatment suggests that the improved survival cannot be due to the early initiation of dialysis. Although the lack of an internal control group and data on dialysis lends uncertainty, the large difference in mortality rate between these patients and the nationwide experience indicates that protein restriction and close clinical monitoring predialysis does not worsen and may substantially improve survival during the first 2 yr on dialysis. These findings point out the importance of studying predialysis treatments as a means for lowering mortality on dialysis.

Green tea extract intake during lactation modified cardiac macrophage infiltration and AMP-activated protein kinase phosphorylation in weanling rats from undernourished mother during gestation and lactation

2016 ◽  
Vol 8 (2) ◽  
pp. 178-187 ◽  
Author(s):  
E. Matsumoto ◽  
S. Kataoka ◽  
Y. Mukai ◽  
M. Sato ◽  
S. Sato
Keyword(s):  
Protein Kinase ◽  
Green Tea ◽  
Control Diet ◽  
Protein Restriction ◽  
Protein Diet ◽  
Macrophage Infiltration ◽  
Low Protein Diet ◽  
Low Protein ◽  
Tea Extract ◽  
Amp Activated Protein Kinase

Maternal dietary restriction is often associated with cardiovascular disease in offspring. The aim of this study was to investigate the effect of green tea extract (GTE) intake during lactation on macrophage infiltration, and activation of adenosine monophosphate (AMP)-activated protein kinase (AMPK) and serine-threonine kinase Akt (Akt) in the hearts of weanlings exposed to maternal dietary protein restriction. Pregnant Wistar rats were fed control (C) or low-protein diets (LP) throughout gestation. Following delivery, the dams received a control or a GTE-containing control diet during lactation: control diet during gestation and lactation (CC), low-protein diet during gestation and lactation (LPC), low-protein diet during gestation and 0.12% GTE-containing low-protein diet during lactation (LPL), and low-protein diet during gestation and 0.24% GTE-containing low-protein diet during lactation (LPH). The female offspring were sacrificed at day 22. Biochemical parameters in the plasma, macrophage infiltration, degree of fibrosis and expression levels of AMPK and Akt were examined. The plasma insulin level increased in LPH compared with LPC. Percentage of the fibrotic areas and the number of macrophages in LPC were higher than those in CC. Conversely, the fibrotic areas and the macrophage number in LPH were smaller (21 and 56%, respectively) than those in LPC. The levels of phosphorylated AMPK in LPL and LPH, and Akt in LPH were greater than those in LPC. In conclusion, maternal protein restriction may induce macrophage infiltration and the decrease of insulin levels. However, GTE intake during lactation may suppress macrophage infiltration and restore insulin secretion function via upregulation of AMPK and insulin signaling in weanlings.

scholarly journals The relative effects of a low-protein-high-carbohydrate diet on the free amino acid composition of liver and muscle

1976 ◽  
Vol 36 (2) ◽  
pp. 219-230
Author(s):  
P. G. Lunn ◽  
R. G. Whitehead ◽  
B. A. Baker
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Acid Concentration ◽  
Free Amino ◽  
Essential Amino Acids ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Total Amino Acid ◽  
Low Protein

1. Free amino acid concentrations in the plasma have been compared with those in liver and quadriceps muscle, in rats fed on diets containing 209 (control) and 31 (low-protein) g protein/kg. The effects of the low-protein diet on diurnal variations in these values were also measured.2. In the plasma, the total amino acid concentration was significantly lower in animals given the low-protein diet, at all times of day except 12.00 hours. In the liver, and to a lesser extent the muscle, total amino acid concentration was maintained.3. In the control animals, diurnal variation in the concentrations of both essential and non-essential amino acids was very similar in plasma, liver and muscle. In animals given the low-protein diet, although the same diurnal pattern was maintained for non-essential amino acids, that occurring among the essential amino acids had virtually disappeared.4. In plasma, the mean 24 h concentration of essential amino acids decreased from 24· mmol/l in control animals to only 1·29 mmol/l in the low-protein-fed animals. Concentrations in muscle and liver were reduced by a similar proportion (from 8·6 to 5·56 μmol/g and from 8·67 to 5·05 μmol/g respectively). Conversely the concentrations of non-essential amino acids in animals given the low-protein diet were increased in plasma (from 1·53 to 2·00 mmol/l), muscle (from 12·5 to 14·3 μmol/g), and liver (from 16·8 to 20·5 μmol/g), muscle showing the lowest increase.5. With the exceptions of lysine, threonine, cystine and tyrosine, the concentrations of all other essential amino acids were reduced more in liver than in muscle. The relationship between this and the failure to maintain plasma albumin concentrations is discussed.

scholarly journals Tau‐induced brain atrophy and neuroinflammation accelerated by low‐protein diet and decelerated by selected essential amino acids in a murine model of tauopathies

2020 ◽  
Vol 16 (S2) ◽  
Author(s):  
Yuhei Takado ◽  
Hideaki Sato ◽  
Masako Tsukamoto‐Yasui ◽  
Keiichiro Minatohara ◽  
Manami Takahashi ◽  
...  
Keyword(s):  
Amino Acids ◽  
Murine Model ◽  
Brain Atrophy ◽  
Essential Amino Acids ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Low Protein

Effects of low protein diet and low protein diet supplemented with synthetic essential amino acids on meat quality of broiler chickens

2012 ◽  
Vol 84 (6) ◽  
pp. 489-495 ◽  
Author(s):  
Hiroyuki Kobayashi ◽  
Kazuki Nakashima ◽  
Aiko Ishida ◽  
Akane Ashihara ◽  
Masaya Katsumata
Keyword(s):  
Amino Acids ◽  
Meat Quality ◽  
Broiler Chickens ◽  
Essential Amino Acids ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Low Protein

scholarly journals Serum metabolites associated with dietary protein intake: results from the Modification of Diet in Renal Disease (MDRD) randomized clinical trial

2019 ◽  
Vol 109 (3) ◽  
pp. 517-525 ◽  
Author(s):  
Casey M Rebholz ◽  
Zihe Zheng ◽  
Morgan E Grams ◽  
Lawrence J Appel ◽  
Mark J Sarnak ◽  
...  
Keyword(s):  
Glomerular Filtration Rate ◽  
Amino Acid ◽  
Dietary Protein ◽  
Protein Intake ◽  
Filtration Rate ◽  
Protein Diet ◽  
Low Protein Diet ◽  
Dietary Protein Intake ◽  
Low Protein ◽  
P 16

ABSTRACT Background Accurate assessment of dietary intake is essential, but self-report of dietary intake is prone to measurement error and bias. Discovering metabolic consequences of diets with lower compared with higher protein intake could elucidate new, objective biomarkers of protein intake. Objectives The goal of this study was to identify serum metabolites associated with dietary protein intake. Methods Metabolites were measured with the use of untargeted, reverse-phase ultra-performance liquid chromatography–tandem mass spectrometry quantification in serum specimens collected at the 12-mo follow-up visit in the Modification of Diet in Renal Disease (MDRD) Study from 482 participants in study A (glomerular filtration rate: 25–55 mL · min−1 · 1.73 m−2) and 192 participants in study B (glomerular filtration rate: 13–24 mL · min−1 · 1.73 m−2). We used multivariable linear regression to test for differences in log-transformed metabolites (outcome) according to randomly assigned dietary protein intervention groups (exposure). Statistical significance was assessed at the Bonferroni-corrected threshold: 0.05/1193 = 4.2 × 10−5. Results In study A, 130 metabolites (83 known from 28 distinct pathways, including 7 amino acid pathways; 47 unknown) were significantly different between participants randomly assigned to the low-protein diet compared with the moderate-protein diet. In study B, 32 metabolites (22 known from 8 distinct pathways, including 4 amino acid pathways; 10 unknown) were significantly different between participants randomly assigned to the very-low-protein diet compared with the low-protein diet. A total of 11 known metabolites were significantly associated with protein intake in the same direction in both studies A and B: 3-methylhistidine, N-acetyl-3-methylhistidine, xanthurenate, isovalerylcarnitine, creatine, kynurenate, 1-(1-enyl-palmitoyl)-2-arachidonoyl-GPE (P-16:0/20:4), 1-(1-enyl-stearoyl)-2-arachidonoyl-GPE (P-18:0/20:4), 1-(1-enyl-palmitoyl)-2-arachidonoyl-GPC (P-16:0/20:4), sulfate, and γ-glutamylalanine. Conclusions Among patients with chronic kidney disease, an untargeted serum metabolomics platform identified multiple pathways and metabolites associated with dietary protein intake. Further research is necessary to characterize unknown compounds and to examine these metabolites in association with dietary protein intake among individuals without kidney disease. This trial was registered at clinicaltrials.gov as NCT03202914.

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