Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Studies were made on memory of the rhythmic change in activity of duodenal alkaline phosphatase in rats. During starvation, the peak enzyme activity decreased gradually disappearing in 4 days. The peak activity of duodenal alkaline phosphatase was retained by feeding starch diet for 4 days instead of starvation for 4 days, but not by feeding casein diet for the same period. Starvation for one day after feeding casein diet for 4 days resulted in disappearance of the peak activity. However, the peak activity was still retained after one day of starvation after 4 days on starch diet. Therefore, starch feeding appears to be important in the memory of the rhythmic change in activity of duodenal alkaline phosphatase.
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PMID:Memory of the rhythmic change in activity of duodenal alkaline phosphatase in rats. 686 51

Changes in the lobular distribution of liver glycogen were studied during the prolonged fasting of young adult male Sprague-Dawley rats that were previously adapted to a 30% casein diet and to the 2 + 22 controlled feeding and lighting schedule. The optical density of glycogen, revealed in fixed liver cryostat sections by the periodic acid-Schiff procedure, was determined in the periportal (P), midlobular (M), and centrilobular (C) regions of the liver lobule at various times during a 196-hour fasting period. The prolonged fast could be divided into 3 phases with respect to liver glycogen variation: initial glycogen depletion, glycogen resurgence, and final glycogen depletion. Glycogen was lost from all regions of the liver lobule during the initial glycogen depletion phase. During the glycogen resurgence phase, a lobular glycogen concentration gradient formed (P greater than M greater than C). The simultaneous occurrence of increasing liver glycogen, increasing liver tyrosine aminotransferase activity, and decreasing body fat during glycogen resurgence suggests that the young adult rat does not spare body protein during starvation. During the final glycogen depletion phase, liver glycogen was again present in a lobular gradient (P greater than M greater than C) but the absolute amount of glycogen in each region of the lobule was markedly reduced in comparison with rats killed during glycogen resurgence.
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PMID:Changes in liver lobule glycogen zonation during prolonged fasting of rats previously fed a 30% casein diet and adapted to a controlled feeding schedule. 707 24

After adaptation of rats to a 90%-casein diet, hepatic uptake of alanine is strikingly increased in vivo, with concomitant appearance of a concentration of favourable for uptake. With a high-protein diet, uptake of 2-aminoisobutyrate by isolated hepatocytes in the presence of various concentrations of substrates suggested induction of the A system (high-affinity system), whose emergence has been reported during starvation or after glucagon treatment. The other system (ASC, L) were characterized: induction processes only affected the A system. Dibutyryl cyclic AMP addition resulted in an increase in 2-aminoisobutyrate transport at low substrate concentration, the response being greater after adaptation to a high-protein diet. Evidence is presented suggesting that the increased uptake of amino acids by the liver of rats fed on high-protein diets is obtained by developing favourable gradients and enhancing transport capacities. These adaptations allow sufficient amounts of amino acids to enter the liver, where accelerated metabolism plays a decisive role.
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PMID:Stimulation of amino acid transport into liver cells from rats adapted to a high-protein diet. 712 87

Branched-chain alpha-keto and amino acid (BCKA, BCAA) concentrations were measured in blood, plasma, and tissues of rats fed low protein (8% casein) or high protein (60% casein) diets; and in rats fed a stock diet and subjected to 3 days of starvation of chemically-induced diabetes. Concentrations of these amino and ketoacids were also measured in blood from patients with maple syrup urine disease. Valine, isoleucine, and leucine concentrations in blood from rats fed the stock diet were 124 +/- 7, 58 +/- 4 and 99 +/- 5 microM, respectively. Blood BCAA concentrations of rats fed the high protein diet and diabetic rats were elevated 2- to 3-fold; small increases were observed in blood from starved rats. Changes in blood BCAA concentrations paralleled those in tissues, except in starved rats in which the skeletal muscle free BCAA pool increased proportionately more than the circulating pool. Mean blood BCKA concentrations of rats fed the stock diet were low--7.9 +/- 0.5, 7.1 +/- 0.4 and 12.4 +/- 0.7 microM for alpha-ketoisovaleric, alpha-keto-beta-methylvaleric, and alpha ketoisocaproic acids, respectively. All treatments resulted in increases in blood BCKA concentrations of from 1.4 to 2 fold. In liver and heart, concentrations of BCKA, except for that of alpha-ketoisocaproic acid were near the limits of detection (less than 1 nmole/g). There was significant accumulation of all three BCKA in skeletal muscle which was estimated to contain about 80% of the measured body free BCKA pool. Blood BCKA are well regulated. Only in patients with maple syrup urine disease are plasma concentrations of BCKA useful indicators of altered tissue BCAA metabolism. Skeletal muscle, where oxidation of the BCKA is limited by low BCKA dehydrogenase activity, would seem to be the major source of circulating BCKA.
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PMID:Blood and tissue branched-chain amino and alpha-keto acid concentrations: effect of diet, starvation, and disease. 721 22

In rats kept under starvation for 25 h after bilateral nephrectomy VO2 is reduced to about 50% of the normal value. The body temperature is conspicuously low (33--34 degrees C), the blood pH about 7.1. Raising the body temperature to normal values by keeping the rats in a thermostat does not influence the low metabolic rate. The prevention of acidosis by repeated application of bicarbonate in the postoperative period has no effect on VO2. Tube feeding with glucose + oil or glucose + oil + casein does not improve the metabolic rate. However, the total glycerol plasma levels, already high in the state of starvation, are still more elevated. It is considered that the primary effect of acute uremia is to suppress the metabolism, as a consequence of which the body temperature is lowered.
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PMID:Energy metabolism in acute uremic rats. 738 38

The present study was carried out to compare the effects of four isoenergetic and isonitrogenous diets on the N utilization, total serum protein concentration and serum amino acid profile in starved rats at weaning. These diets differed only in the molecular form of two milk proteins (whey protein and casein), which were either native or partly hydrolysed. Male Wistar rats at weaning were fasted for 3 d and then refed with one of the four diets for 48 h. No differences were observed in the body weight gain, protein digestibility and total serum protein concentration between groups after the refeeding period and all the N balances were positive. N retention was higher in the two groups of rats given the protein-hydrolysate-based diets compared with those given the intact-protein-based diets. This was associated with a lower urinary N excretion in rats, given the whey-protein-hydrolysate and the casein-hydrolysate diets. Despite this fact, the serum amino acid pattern of rats given the hydrolysed protein diet was very similar to that of those given the corresponding native protein diet. In conclusion, we have proved that enzymic hydrolysates from milk proteins have equivalent effects to native proteins in recovery after starvation in rats at weaning, on N absorption, total serum protein concentration and serum amino acid profile, and even give a higher N retention. We did not observe any harmful effect in using protein hydrolysates instead of native proteins.
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PMID:Protein v. enzymic protein hydrolysates. Nitrogen utilization in starved rats. 785 16

The present study examined whether different proteins have different effects on whole-body protein turnover in adult rats. The rats were either starved, given a protein-free but energy-sufficient diet (1 MJ/kg body weight (BW) per d) or a diet containing intact casein, hydrolysed casein, or hydrolysed soya-bean protein at a level of 9.1 g/kg BW per d. The diets, which were isoenergetic with the same carbohydrate: fat ratio, were given as a continuous intragastric infusion for at least 4 d. During the last 19 h 15N-glycine (a primed continuous infusion) was given intragastrically and 15N was recovered from urinary ammonia and urea during isotope steady state for measurement of protein synthesis and protein degradation. Compared with starvation the protein-free diet decreased N excretion by 75%, probably by increasing the rate of reutilization of amino acids from endogenous proteins for protein synthesis. The protein diets produced a positive N balance which was independent of the protein source. Intact and hydrolysed casein increased protein synthesis 2.6- and 2.0-fold respectively, compared with the protein-free diet. Protein degradation increased 1.4- and 1.2-fold respectively. Hydrolysed soya-bean protein did not increase protein synthesis but decreased protein degradation by 35% compared with the protein-free diet. Compared with the hydrolysed soya-bean protein, intact casein resulted in 2.2- and 2.8-fold higher rates of protein synthesis and degradation respectively. These results are not easily explained by known sources of misinterpretation associated with the 15N-glycine method. Hydrolysed casein and hydrolysed soya-bean protein produced similar concentrations of insulin-like growth factor-1, insulin, glucagon, and corticosterone. The difference in amino acid composition between the dietary proteins was reflected in plasma amino acid composition and this is suggested to be responsible for the different effect on protein turnover. Preliminary results from this study have previously been published in abstract form (Nielsen et al. 1991).
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PMID:Casein and soya-bean protein have different effects on whole body protein turnover at the same nitrogen balance. 791 30

Casein kinase II of Saccharomyces cerevisiae is composed of two distinct catalytic subunits, alpha and alpha', and two distinct regulatory subunits, beta and beta' (Padmanabha, R. and Glover, C. V. C. (1987) J. Biol. Chem. 262, 1829-1835; Bidwai, A. P., Reed, J. C., and Glover, C. V. C. (1994) Arch. Biochem. Biophys. 309, 348-355). We report here the cloning, sequencing, and disruption of the CKB2 gene encoding the beta'-subunit. The deduced amino acid sequence of Ckb2 displays only 40-45% identity to other beta-subunit sequences reported to date, allowing a better definition of conserved features of this protein. Most notable is the conservation of a cysteine-containing sequence, CPX3C-X22-CPXC, which may constitute a novel metal-binding motif. The degree of sequence divergence of Ckb2 is comparable to that of the Drosophila Stellate protein, a testis-specific protein of unknown function, suggesting that the latter may function as a second beta-subunit in Drosophila. CKB2 is located on the right arm of chromosome XV between the HIR2 and WHI2 loci and has not been previously identified genetically. Haploid and homozygous diploid cells harboring a ckb2 null allele are viable, demonstrating that the beta'-subunit does not have an essential function distinct from that of beta. Strains lacking a functional CKB2 gene appear to grow normally on both fermentable and non-fermentable carbon sources, mate and sporulate normally, and display normal resistance to nitrogen starvation and heat shock. However, haploid strains harboring disruptions of both the beta' gene and either of the catalytic subunit genes exhibit a synthetic phenotype consisting of slow growth and flocculation in rich glucose medium. The occurrence of this synthetic phenotype implies that the beta'-subunit interacts physically and/or functionally with both the alpha- and alpha'-subunits in vivo.
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PMID:Cloning and disruption of CKB2, the gene encoding the 32-kDa regulatory beta'-subunit of Saccharomyces cerevisiae casein kinase II. 802 80

Butyrolactone I is a selective inhibitor of the cyclin-dependent kinase (cdk) family. It inhibits both cdk2 and cdc2 kinase, but scarcely affects C-kinase, A-kinase, casein kinases, MAP kinase or EGF receptor-tyrosine kinase (Kitagawa et al., 1993, Oncogene, 8, 2425-2432). We studied the effects of butyrolactone I on the cell cycle as well as on phosphorylation of retinoblastoma protein (pRB). Butyrolactone I inhibited phosphorylation of pRB catalyzed by cyclin A-cdk2 produced by baculovirus in vitro. Furthermore, it inhibited phosphorylation of pRB and cell cycle progression from G1 to S phase in WI38 cell cultures. WI38 cells arrested at the G0 phase by serum starvation progressed in the cell cycle after serum stimulation. pRB was phosphorylated after 10 h serum stimulation. Incorporation of [3H]thymidine into the cells began to increase after 16 h serum stimulation. These processes were inhibited by butyrolactone I. Flow cytometric analysis showed that exposure to butyrolactone I inhibited progression of the cell cycle from G1 to S phase. These data suggested that initiation of DNA synthesis was inhibited by butyrolactone I and that the cell cycle was arrested in the G1 phase. Butyrolactone I also inhibited H1 histone phosphorylation in human WI38 cells and their G2/M progression. tsFT210 cells, a temperature-sensitive cdc2 mutant cell line, were synchronized at G2/M at a nonpermissive temperature, butyrolactone I inhibited the cell cycle progression of these cells at G2/M at the permissive temperature. Thus butyrolactone I, a cyclin-dependent kinase family inhibitor, which prevented the phosphorylations of the cell cycle-regulating proteins pRB and H1 histone, inhibited the cell cycle at G1/S and G2/M, respectively. These results suggest that the phosphorylations of pRB and H1 histone may play crucial roles in G1/S and G2/M progression, respectively, although it is possible that phosphorylations of other proteins by cdks are involved in G1/S and G2/M progression.
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PMID:A cyclin-dependent kinase inhibitor, butyrolactone I, inhibits phosphorylation of RB protein and cell cycle progression. 805 18

The present study was performed to determine the stage of the erythropoietic pathway which is affected by starvation or protein deprivation and whose manifestation is a depressed response to exogenous erythropoietin (EPO). The response to recombinant human EPO was measured in post-hypoxic polycythemic mice by determination of 59Fe uptake into red cells, spleen and femur and/or erythroid colony forming units (CFU-E) and erythroid precursor cell concentrations in femoral marrow. Experimental mice were either starved or fed one of seven different diets whose protein (casein) content ranged from 0 to 20%. All diets were isocaloric. The response of mice maintained on the standard diet (Purina Lab chow) was taken as the normal one. Starvation during the 48-hour period immediately before EPO injection had no effect on the response to the hormone. Starvation, and protein deprivation to a lesser extent, during the 48-hour period following EPO, on the other hand, significantly reduced the response. There was a progressive increase in the response as the casein content of the diet was increased. A normal response was observed when dietary casein concentration was 10%. These findings indicate that nutritional deprivation or dietary protein alterations during the period immediately following EPO injection in polycythemic mice can have detrimental effects on the erythroid response in a model in which nutritional deprivation was relatively short and acute. They also indicate that the subnormal response is not due to a decreased size of the erythroid progenitor pool available for differentiation but to deficient rates of differentiation of erythropoietic units.
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PMID:Impaired response of polycythemic mice to erythropoietin induced by protein starvation imposed after hormone administration. 840 Dec 52


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