scholarly journals DIET AND TISSUE GROWTH

1927 ◽  
Vol 46 (1) ◽  
pp. 27-41 ◽  
Author(s):  
Theodore S. Moise ◽  
Arthur H. Smith
Keyword(s):  
High Protein Diet ◽  
Experimental Period ◽  
Tissue Growth ◽  
High Protein ◽  
Standard Diet ◽  
Focal Lesions ◽  
Renal Lesions ◽  
White Rats ◽  
Age Factor ◽  
Standard Ration

The effects of the ingestion of diets containing different concentrations of protein on the remaining kidney in adult white rats after a unilateral nephrectomy has been studied. In the animals on the high protein diet (85 per cent casein), actual glomerular and tubular lesions were observed in the kidneys of animals maintained for 90, 120 and 150 days after nephrectomy. In the animals on the standard ration, 18 per cent casein, no significant renal lesions were observed within the experimental period. Spontaneous focal lesions in the kidneys of rats maintained on Sherman's diets "A" and "B" were inconspicuous at the age of 350 days but became progressively more frequent and were commonly observed after 500 days. The animals on the high protein and standard rations were all under 350 days old at the completion of the experiment. It is suggested that the age factor is of importance in that young animals may have greater powers of adaptation in withstanding the injurious effect of high protein rations. The animals on the high protein ration excreted definitely larger quantities of protein in the urine, and showed a higher incidence of casts in periods roughly corresponding to those in which anatomic lesions were observed than did the rats on the standard diet.

Interactions of insulin-like growth factor (IGF)-II and growth hormone in vivo: circulating levels of IGF-I and IGF-binding proteins in transgenic mice

1997 ◽  
pp. 701-708 ◽  
Author(s):  
A Blackburn ◽  
RA Dressendorfer ◽  
WF Blum ◽  
M Erhard ◽  
G Brem ◽  
...  
Keyword(s):  
Transgenic Mice ◽  
Transgene Expression ◽  
High Protein Diet ◽  
High Protein ◽  
Protein Diet ◽  
Standard Diet ◽  
Igf I ◽  
Igf Binding ◽  
B Mice

To study interactions between insulin-like growth factor-II (IGF-II) and growth hormone (GH) in vivo, we crossed hemizygous transgenic mice carrying phosphoenolpyruvate carboxykinase (PEPCK)-IGF-II fusion genes with hemizygous PEPCK-bovine GH (bGH) transgenic mice. Offspring harbouring both transgenes (IB), the IGF-II transgene (I) or the bGH transgene (B), and non-transgenic littermates (C) were obtained. Blood samples were taken before (end of week 12) and after (end of week 14) the mice had received a diet high in protein and low in carbohydrates to stimulate PEPCK promoter-controlled transgene expression. Mean serum GH concentrations of both B and IB mice corresponded to 900 ng/ml and increased more than twofold (P < 0.001) after 1 week of the high-protein diet. GH concentrations in controls and I mice were less than 20 ng/ml. Serum IGF-II concentrations in I and IB mice were three-to fourfold higher than those in C and B mice. Whereas IGF-II concentrations were not changed by the high-protein diet in the last two groups, serum IGF-II increased significantly in I (P < 0.001) and IB mice (P < 0.05). This increase was significantly (P < 0.05) less pronounced in IB than in C and I mice. Circulating IGF-I concentrations were about twofold (P < 0.001) higher in B and IB than in C and I mice, and showed a tendency to be lower in I than in C and in IB than in B mice when animals were maintained on the standard diet. The high-protein diet did not change circulating IGF-I concentrations in controls and B mice, but resulted in a significant reduction of serum IGF-I concentrations in I (P < 0.05) and IB mice (P < 0.001). Consequently, after PEPCK-IGF-II transgene expression was stimulated, serum IGF-I concentrations were significantly (P < 0.05) lower in I than in C and in IB than in B mice. Serum IGF-binding protein (IGFBP)-2 concentrations were significantly (P < 0.05) higher in I mice than in all other groups when mice were maintained on the standard diet, with a tendency to reduced IGFBP-2 concentrations in B mice. After the high-protein diet, serum IGFBP-2 concentrations did not change in C and I mice, but increased by two- to threefold in B and IB mice (P < 0.001). Serum IGFBP-3 concentrations tended to be greater in B and IB than in C and I mice, but these differences were mostly not significant. IGFBP-4 concentrations were significantly (P < 0.001) increased by GH overproduction in B and IB mice. Our data suggest that the reduction in circulating IGF-I concentrations by increased IGF-II is most probably due to the limited serum IGF binding capacity and the short half-life of free IGFs, rather than to a reduction in GH-dependent IGF-I production. Effects of GH overproduction on serum IGFBP-2 concentrations depend on dietary factors and may be both inhibitory and stimulatory.

scholarly journals Adaptive changes in the capacity of systems used for the synthesis of citrulline in rat liver mitochondria in response to high- and low-protein diets

1974 ◽  
Vol 142 (2) ◽  
pp. 359-364 ◽  
Author(s):  
J. D. McGivan ◽  
Norah M. Bradford ◽  
J. B. Chappell
Keyword(s):  
Nitrogen Source ◽  
High Protein Diet ◽  
Liver Mitochondria ◽  
High Protein ◽  
Protein Diet ◽  
Rat Liver Mitochondria ◽  
Standard Diet ◽  
Adaptive Changes ◽  
Low Protein ◽  
Citrulline Synthesis

1. Citrulline synthesis was measured in mitochondria from rats fed on a standard diet, a high-protein diet, or on glucose. 2. With NH4Cl as the nitrogen source the rate of citrulline synthesis was higher in mitochondria from rats fed on a high-protein diet than in those from rats fed on a standard diet. When rats were fed solely on glucose the rate of synthesis of citrulline from NH4Cl was very low. 3. With glutamate as the nitrogen source the relative rates of citrulline synthesis were much lower than when NH4Cl was present, but similar adaptive changes occurred. 4. The activity of the mitochondrial glutamate-transporting system increased two to three times on feeding rats on a high-protein diet, but the Km for glutamate was unchanged. 5. Adaptive changes in certain intramitochondrial enzymes were also measured. 6. The results were interpreted to indicate that when an excess of substrate was present, citrulline synthesis from NH4Cl was rate-limited by the intramitochondrial concentration of N-acetyl-glutamate, but citrulline synthesis from glutamate was rate-limited primarily by the activity of the glutamate-transporting system.

Glomerular size selectivity in nephrotic rats exposed to diets with different protein content

1987 ◽  
Vol 253 (2) ◽  
pp. F318-F327
Author(s):  
A. Remuzzi ◽  
C. Battaglia ◽  
L. Rossi ◽  
C. Zoja ◽  
G. Remuzzi
Keyword(s):  
High Protein Diet ◽  
Urinary Protein Excretion ◽  
Urinary Protein ◽  
High Protein ◽  
Protein Diet ◽  
Standard Diet ◽  
Size Selectivity ◽  
Protein Excretion ◽  
Fractional Clearance ◽  
Glomerular Size

Glomerular size-selective properties in animals made nephrotic by adriamycin (ADR) injection and fed standard (20% protein) or high-protein (35% protein) diets were investigated using dextran fractional clearances. To interpret filtration and dextran-sieving data, a theoretical approach previously developed for analysis of experimental data in healthy and nephrotic humans was used. Four types of hypothetical pore-radius distributions were compared in order to establish the best tool for describing membrane pore structure in normal and nephrotic rats. This analysis revealed that a spread distribution of pores, the lognormal probability distribution, is the most adequate in representing membrane intrinsic characteristics. ADR animals on standard diet developed massive proteinuria and a lower glomerular filtration rate (GFR) than control animals. High-protein feeding in ADR rats induced a further increase in urinary protein excretion and in GFR. Dextran fractional clearance was more elevated for larger dextran fractions (greater than 46 A) in ADR animals on the standard diet than in control rats. No differences were observed in dextran-sieving curves between ADR rats on the standard and high-protein diet. Theoretical analysis of filtration and fractional clearance data revealed comparable changes in the intrinsic parameters of glomerular size selectivity in the two groups of nephrotic animals. These observations indicate that increased traffic of plasma proteins through the glomerular capillary wall does not imply, in our experimental condition, a further loss of glomerular size-selective properties. The greater urinary protein excretion of ADR animals on high-protein diet than ADR animals on a standard diet cannot be explained by further impairment of glomerular size selectivity but more likely reflects hemodynamic changes.

scholarly journals High Protein Diet Induces Oxidative Stress in Rat Cerebral Cortex and Hypothalamus

2019 ◽  
Vol 20 (7) ◽  
pp. 1547 ◽  
Author(s):  
Ewa Żebrowska ◽  
Mateusz Maciejczyk ◽  
Małgorzata Żendzian-Piotrowska ◽  
Anna Zalewska ◽  
Adrian Chabowski
Keyword(s):  
Oxidative Stress ◽  
Cerebral Cortex ◽  
Oxidative Damage ◽  
Antioxidant Defense ◽  
High Protein Diet ◽  
Brain Structures ◽  
High Protein ◽  
Protein Diet ◽  
Standard Diet ◽  
The Impact

This is the first study to analyze the impact of high protein diet (HPD) on antioxidant defense, redox status, as well as oxidative damage on both a local and systemic level. Male Wistar rats were divided into two equal groups (n = 9): HPD (44% protein) and standard diet (CON; 24.2% protein). After eight weeks, glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase-1 (SOD-1), reduced glutathione (GSH), uric acid (UA), total antioxidant (TAC)/oxidant status (TOS) as well as advanced glycation end products (AGE), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) were analyzed in the serum/plasma, cerebral cortex, and hypothalamus of HPD and CON rats. HPD resulted in higher UA concentration and activity of GPx and CAT in the hypothalamus, whereas in the cerebral cortex these parameters remained unchanged. A significantly lower GSH content was demonstrated in the plasma and hypothalamus of HPD rats when compared to CON rats. Both brain structures expressed higher content of 4-HNE and MDA, whereas AGE was increased only in the hypothalamus of HPD animals. Despite the enhancement in antioxidant defense in the hypothalamus, this mechanism does not protect the hypothalamus from oxidative damage in rats. Hypothalamus is more susceptible to oxidative stress caused by HPD.

scholarly journals High-Protein Dietary Supplementation and Nutritional Status Improvement of Malnourished Patients in Hospital Care

2021 ◽  
Vol 22 (2) ◽  
pp. 147-153
Author(s):  
Marcellus Simadibrata ◽  
Fiastuti Witjaksono ◽  
Yohannessa Wulandari ◽  
Raja Mangatur Haloho ◽  
Rabbinu Rangga Pribadi ◽  
...  
Keyword(s):  
Hospital Care ◽  
Healthcare Providers ◽  
High Protein Diet ◽  
High Protein ◽  
Food Supplementation ◽  
Standard Diet ◽  
Liquid Form ◽  
Protein Food ◽  
Suitable Alternative ◽  
Hospital Malnutrition

Hospital malnutrition is common in Indonesia and other developing countries. In Asia, the prevalence of hospital malnutrition ranges between 27-39%. The causes of malnutrition in hospital care include insufficient food intake and increased catabolic processes due to underlying causes such as metabolic disease, infection, and malignancy. Several studies have demonstrated that malnutrition increases the morbidity and mortality of hospitalized patients, prolongs hospital stay, and delays recovery. Therefore, healthcare providers must recognize malnutrition early by conducting nutritional screening and assessment to prevent worsening of malnutrition and administer the optimal nutritional therapy to patients. Apart from giving a standard diet, high-protein food supplementation in liquid form remains a suitable alternative for patients, especially since it is easily digestible. A high protein diet is associated with a better mortality rate, better weight gain, and improved SGA score in patients.

scholarly journals Stability of the mRNA encoding some pancreatic hydrolases is modulated by dietary protein intake in the rat

1997 ◽  
Vol 78 (5) ◽  
pp. 833-843 ◽  
Author(s):  
Suzanne Carreira ◽  
Christian Fueri ◽  
Jean-Claude Chaix ◽  
Antoine Puigserver
Keyword(s):  
Dietary Protein ◽  
Actinomycin D ◽  
Blot Hybridization ◽  
High Protein Diet ◽  
High Protein ◽  
Standard Diet ◽  
Dot Blot ◽  
Pancreatic Cells ◽  
The Stability ◽  
Protein Free Diet

Wistar rats fed on either a high-protein or a protein-free diet were examined to determine their pancreatic hydrolase mRNA stabilities in comparison with those of control animals receiving a standard diet. Actinomycin D was used to inhibit transcription and, after isolating the pancreatic RNA, the specific messengers were quantified by performing dot-blot hybridization with cDNA probes. In the rats fed on a high-protein diet, only the half-lives of anionic trypsinogen I and elastase I (EC 3.4.21.36) were affected. Interestingly, when rats were fed on the protein-free diet, most of the hydrolase mRNA half-lives showed changes, except that corresponding to lipase. In these rats, the half-life values of the mRNA coding for anionic trypsinogen I, chymotrypsinogen and procarboxypeptidase B increased, in sharp contrast with those of the amylase and elastase I mRNA, which decreased. These results strongly suggest that the mechanism whereby the biosynthesis of pancreatic hydrolases is regulated, depending on the presence or absence of proteins in the diet, is not unique and provide evidence that the stability of mRNA encoding most, if not all, the hydrolases in pancreatic cells is modulated by the dietary protein content.

scholarly journals High-protein diet accelerates diabetes and kidney disease in the BTBRob/ob mouse

2020 ◽  
Vol 318 (3) ◽  
pp. F763-F771 ◽  
Author(s):  
Anna Björnson Granqvist ◽  
Anette Ericsson ◽  
José Sanchez ◽  
Pernilla Tonelius ◽  
Lena William-Olsson ◽  
...  
Keyword(s):  
Kidney Disease ◽  
Mouse Model ◽  
Interstitial Fibrosis ◽  
High Protein Diet ◽  
Human Kidney ◽  
Fold Change ◽  
High Protein ◽  
Protein Diet ◽  
Standard Diet ◽  
Chronic Injury

There is a need for improved animal models that better translate to human kidney disease to predict outcome of pharmacological effects in the patient. The diabetic BTBR ob/ob mouse model mimics key features of early diabetic nephropathy in humans, but with chronic injury limited to glomeruli. To explore if we could induce an accelerated and more advanced disease phenotype that closer translates to human disease, we challenged BTBR ob/ob mice with a high-protein diet (HPD; 30%) and followed the progression of metabolic and renal changes up to 20 wk of age. Animals on the HPD showed enhanced metabolic derangements, evidenced by further increased levels of glucose, HbA1C, cholesterol, and alanine aminotransferase. The urinary albumin-to-creatinine ratio was markedly increased with a 53-fold change compared with lean controls, whereas BTBR ob/ob mice on the standard diet only presented an 8-fold change. HPD resulted in more advanced mesangial expansion already at 14 wk of age compared with BTBR ob/ob mice on the standard diet and also aggravated glomerular pathology as well as interstitial fibrosis. Gene expression analysis revealed that HPD triggered expression of markers of fibrosis and inflammation in the kidney and increased oxidative stress markers in urine. This study showed that HPD significantly aggravated renal injury in BTBR ob/ob mice by further advancing albuminuria, glomerular, and tubulointerstitial pathology by 20 wk of age. This mouse model offers closer translation to humans and enables exploration of new end points for pharmacological efficacy studies that also holds promise to shorten study length.

scholarly journals Mammary sensitivity to protein restriction and re-alimentation

1996 ◽  
Vol 76 (3) ◽  
pp. 423-434 ◽  
Author(s):  
M. G. Goodwill ◽  
N. S. Jessop ◽  
J. D Oldham
Keyword(s):  
Cell Activity ◽  
High Protein Diet ◽  
Experimental Period ◽  
Dry Mass ◽  
High Protein ◽  
Protein Diet ◽  
Synthetase Activity ◽  
Lactation Period ◽  
Sprague Dawley ◽  
Ad Libitum

The present study tested the influence of protein undernutrition and re-alimentation on mammary gland size and secretory cell activity in lactating rats. During gestation, female Sprague-Dawley rats were offered a high-protein diet (215 g crude protein (N x 625; CP)/kg DM; H); litters were standardized to twelve pups at parturition. During lactation, two diets were offered ad libitum, diet H and a low- protein diet (90 g CP/kg DM; L). Lactational dietary treatments were the supply ad libitum of either diet H (HHH) or diet L (LLL) for the first 12 d of lactation, or diet L transferring to diet H on either day 6 (LHH) or 9 (LLH) of lactation. On days 1, 6, 9 and 12 of lactation, rats from each group (n > 6) were used to estimate mammary dry mass, fat, protein, DNA and RNA; the activities of lactose synthetase (EC 2.4.1.22) enzyme and Na+, K+-ATPase (EC 3.6.1.37) were also measured. Rats offered a diet considered protein sufficient (H) from day 1 of lactation showed a decrease in mammary dry mass and fat but an increase in DNA, RNA and protein on day 6, after which there was no further change, except for mammary protein which continued to increase. However, rats offered diet L showed a steady loss in mammary mass and fat throughout the 12 d lactation period and no change in mammary DNA, RNA or protein. Rats previously protein restricted for either the first 6 or 9 d of lactation had their mammary dry mass and mammary fat loss halted and showed a rapid increase in mammary DNA, RNA and protein on re-alimentation. Lactose production in group HHH, as measured by lactose synthetase activity, was similar on days 1 and 6 of lactation, after which a significant increase was seen. Protein- restricted rats showed no change in lactose synthetase activity during the 12 d experimental period. Changing from diet L to diet H led to a significant increase in lactose synthetase activity to levels comparable with those offered diet H from day 1. These results show that rats offered a protein-restricted diet during lactation suffer mammary underdevelopment, but this may be rapidly reversed by re-alimentation with a high-protein diet

Urea-salt block supplementation of adult Merino wethers grazing wheat stubble in Western South Australia

1971 ◽  
Vol 11 (49) ◽  
pp. 153
Author(s):  
JJ Messenger ◽  
IM Donald ◽  
DC Brown
Keyword(s):  
South Australia ◽  
High Protein Diet ◽  
Experimental Period ◽  
High Protein ◽  
Protein Diet ◽  
Wool Production ◽  
Wheat Stubble ◽  
Ad Libitum

Blocks containing 30 and 35 per cent urea were offered to adult Merino wethers grazing wheat stubble during summer and autumn of 1965. Two groups of sheep were supplemented with two different urea-salt blocks while a third group had no supplement. Urea consumption from the two blocks was 5.3 and 7.2 g per sheep per day. Supplemented sheep had a significantly higher (P<0.05) apparent herbage consumption, but showed less selectivity in grazing for a high protein diet. Supplemented sheep had significantly higher (Pt0.05) liveweights, but four months after the experimental period there were no significant liveweight differences. Supplementation had no effect on wool production. Although the sheep had ad libitum access to the blocks no cases of urea toxicity were reported.

Growth and carcass traits in pigs after selection for lean tissue growth rate on low and high protein diets

1995 ◽  
Vol 61 (2) ◽  
pp. 341-346 ◽  
Author(s):  
S. Stern ◽  
N. Lundeheim ◽  
K. Andersson
Keyword(s):  
Growth Rate ◽  
High Protein Diet ◽  
Tissue Growth ◽  
High Protein ◽  
Protein Diet ◽  
Lean Tissue ◽  
Commercial Diet ◽  
Low Protein ◽  
Selection For ◽  
High Protein Diets

AbstractTwo lines of pigs that had been selected for five generations for lean tissue growth rate (LTGR) on a high (HP) or low (LP) protein diet were evaluated on a commercial diet (165 g crude protein per kg diet). The growth characteristics of 534 animals were measured, and carcass data were obtained on 405 animals. Differences between lines were tested for significance taking genetic drift into account. The animals from the HP-line grew faster both before and during the test and were 6·5 days younger at slaughter than the LP-line pigs. The HP-line pigs had a higher lean content (587 v. 558 g/kg) and a thinner backfat layer (17·8 v. 22·7 mm) than the LP-line. LTGR was higher in the HP-line (374 v. 347 g/day). No significant differences between lines were found in meat quality or in the incidence of osteochondrosis in elbow or knee. The realized differences between lines confirm that selection for LTGR on a high protein diet was more effective in improving both leanness and growth rate compared with selection for LTGR on a low protein diet.

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