Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020505 (hyperphagia)
 6,116 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We evaluated amount and composition of amino acids in supplementation of hyperalimentation from the standpoint of whether it may improve nutrition and/or reduce the indexes of uremia such as BUN. Rats with established uremia, by 5/6 nephrectomy, were treated with various isocaloric solutions containing different amount of essential amino acids and histidine (EAA) or standard amino acids (SAA) which were formulated to provide Cal/N ratios of 300, 600, and 900. The BUN was lower and the nutritional index was better in rats infused with EAA compared with those administrated SAA, while severe distortion of plasma amino acid concentration, hyperammonemia, and fatty liver were observed at the Cal/N 300 condition. Rats infused with SAA gained positive nitrogen balance at the condition of Cal/N 300; however, plasma amino acid distortion was still observed. These results indicate that administration of EAA alone for treatment of renal failure needs high-calorie and low-nitrogen conditions such as Cal/N 600 for avoiding complications. Administration of standard amino acid solution is safe and nutritionally effective in the Cal/N 300 condition, but there are a few problems concerning nitrogen availability and plasma amino acid pattern.
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PMID:Amino acid supplementation to hyperalimentation in uremic rats: effects of amount and composition of amino acids on nutrition and uremia. 804 60

Diet protein increases whereas carbohydrates decrease urea synthesis. Traditionally, these effects have been explained by changes in substrate supply. Diet protein intake increases whereas carbohydrate decreases blood amino acid concentration. However, glucose also decreases urea synthesis by a hepatic mechanism independent of the decrease in blood amino acid concentration. Whether this is due to an effect of glucose in itself, or whether the fall in glucagon or the rise in insulin is responsible, was not known. This survey deals with the effect of an increase in diet protein intake and of the separate effects of glucose, glucagon and insulin on functional hepatic nitrogen clearance in normal man and in patients with cirrhosis of the liver. The functional hepatic nitrogen clearance is calculated as the slope of the linear regression analysis of alanine-stimulated urea synthesis rate and blood alpha-amino nitrogen concentration, and expresses urea synthesis independent of changes in blood amino acid concentration. In patients with cirrhosis, hepatic nitrogen clearance is reduced in parallel with liver cell mass, despite high glucagon concentration that would normally up-regulate the process. In both healthy subjects and in patients with cirrhosis, an increase in diet protein intake (plus approximately 50 g/day) for 14 days increases hepatic nitrogen clearance by 40%. Thus, in addition to the substrate effect, protein intake increases urea synthesis by an effect in the liver, probably by enzyme formation. What induces this is not clear but high postprandial levels of glucagon may be involved. Although the effect is qualitatively intact in the patients, the response relative to the increase in protein intake is reduced by two-thirds. The effect may be important to control blood amino acid concentration during a high protein diet and may partly explain why patients with cirrhosis usually tolerates protein hyperalimentation without developing hepatic encephalopathy. It is shown that the reduction of hepatic nitrogen clearance by glucose depends on hyperglycaemia, and is accomplished by the additive effects of a direct hormone-independent action of glucose, and indirectly via suppression of glucagon. Insulin is not a direct controller of hepatic nitrogen clearance, but is still considered an important regulator of urea synthesis by its reducing effects on blood amino acid concentration. High experimental glucagon levels overrule the normal suppressive effect of glucose. In contrast, it is shown that the sugar-alcohol xylitol normalises the glucagon induced increase in hepatic nitrogen clearance. During normal glucagon levels xylitol exerts only a very little decrease in hepatic nitrogen clearance. In patients with cirrhosis, glucose does not down-regulate hepatic nitrogen clearance. However, when the spontaneous high glucagon levels are normalised by somatostatin, glucose decreases hepatic nitrogen clearance. This shows that the direct hormone-independent effect of glucose is intact. These findings indicate that the high glucagon levels during spontaneous hormone responses overrule the suppressive effect of glucose. Incomplete glucose suppression of glucagon secretion during alanine infusion contributes to the high glucagon levels. The removal of the high glucagon levels decreases hepatic nitrogen clearance in itself. Thus, the hyperglucagonaemia may be a compensatory mechanism by which the cirrhotic liver to some extent reestablishes its capacity to produce urea. The consequence is the defective down-regulation of hepatic nitrogen clearance by glucose. The reduction in urea synthesis by glucose, i.e. its nitrogen sparing effect, is accomplished by two different mechanisms: A hepatic component (reduction of the hepatic nitrogen clearance) and a peripheral component (reduced substrate availability mediated by the insulin response). This is an extension of former thoughts according to which glucose reduces urea synthesis due solely to
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PMID:Regulation of urea synthesis by diet protein and carbohydrate in normal man and in patients with cirrhosis. Relationship to glucagon and insulin. 923 44

Intravenous hyperalimentation and enteral nutrition are the main surgical nutrition methods. IVH play an active role in therapeutic nutrition, although made rapid progress has been made in enteral nutrition, resulting in its wide clinical application. Branched-chain amino acids are useful in improving the nitrogen balance in patients who have undergone major surgical procedures or significant stress. Furthermore, their superiority over a mixed oral protein diet in patients with hepatic encephalopathy has been confirmed clinically. Medium-chain triglycerides (MCT) are an important energy source. Their advantages include easy absorbtion by the intestinal mucosa, lack of stimulation of insulin excretion, and suppression of the reticuloendothelial system. However, the ratio of long-chain triglyceride (LCT) to MCT should be evaluated in many cases. EPA can prevent various adult diseases. Many nutrients contain EPA and it is clinically used both enterally and parenterally. Glutamine is effective in the repair of small intestinal mucosal damage, since it suppresses bacterial translocation, effects of growth hormone, epidermal growth factor (EGF), and nucleic acid on nutritional status are being evaluated clinically. Home enteral nutrition (HEN) has become more common in the past five years although close, cooperation between medical staff and the family is necessary its success.
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PMID:[Progress of enteral nutrition]. 961 94

Although systemic AA amyloidosis complicating Crohn's disease has been found in 0.5 to 6% in America and Europe, it is relatively rare in Japan. We report a case of systemic AA amyloidosis complicating Crohn's disease. In 1979, a 26-year-old Japanese man presented with diarrhea, melena and perianal abscesses, and was diagnosed as having Crohn's disease. He was treated with oral prednisolone, salazosulfapyridine and diet therapy. However, the gastrointestinal symptoms recurred and he was hospitalized several times. In 1991, his thyroid gland was found to be swollen, but with normal thyroid function, and his thyroid gland became larger subsequently. In October 1995, he showed renal dysfunction (blood urea nitrogen 33.2 mg/dl; serum creatinine 1.5 mg/dl) with proteinuria. His renal function had been deteriorating rapidly. On September 13, 1996, he was admitted to the Tsukuba University Hospital. At the time of admission, his renal function showed a blood urea nitrogen of 129.5 mg/dl with a creatinine of 5.4 mg/dl. The urine contained 0.8 g of protein per 24 hours. He presented with diarrhea for several days before admission and was treated with central venous hyperalimentation. Despite supportive care, he developed end-stage renal failure, then hemodialysis was initiated on October 7. His condition was complicated by a complete auriculoventricular block on October 18. He died of hemoperitoneum on October 25. On postmortem examination, extensive amyloid deposits were found in multiple organs including kidneys, intestine, heart, thyroid gland, lungs, liver, spleen, pancreas, gall bladder, adrenal glands, testis, prostate, bone marrow and parathyroid glands. Analysis of amyloid protein in the autopsy specimens showed type AA.
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PMID:[A case of systemic AA amyloidosis complicating Crohn's disease]. 965 12

We studied the effects of the new amino acid solution MRX-III on the nutritional status and nitrogen metabolism of rats with chronic renal failure (CRF) in comparison with those of a general amino acid solution (MPR-F). The essential amino acids/non-essential amino acids ratio was 3.21 for MRX-III and 1.09 for MPR-F. Rats with CRF, induced by 7/8 renal ablation, were divided into 6 groups of 8 rats each receiving total parenteral nutrition (TPN) containing MRX-III or MPR-F at a non-protein calorie/nitrogen ratio (Cal/N) of 300, 600 or 900 for 7 d. The rats were infused with test solutions containing the same amounts of non-protein calories. The cumulative nitrogen balance, as a nutritional index, in the MRX-III group was significantly higher than that in the MPR-F group at the Cal/N of 600 or 900, and the plasma albumin level at the Cal/N of 300. The plasma transferrin levels at the Cal/N of 900 in the MRX-III groups were significantly higher than those in the corresponding MPR-F groups. At all Cal/N, the MRX-III groups showed low levels of blood urea nitrogen and urinary excretion of ammonia and urea nitrogen as compared with the MPR-F groups at the same Cal/N. The plasma amino acid concentration profiles in the MRX-III groups after TPN showed greater similarity to that in the Normal group as compared with the profiles in the corresponding MPR-F groups. No aggravation of renal failure was observed in any TPN groups during TPN. These results indicate that, in rats with CRF undergoing hyperalimentation, the effects of MRX-III on the nutritional status and nitrogen metabolism are superior to those of the general amino acid solution, MPR-F. It is suggested that MRX-III could safely provide adequate amounts of nitrogen during hyperalimentation.
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PMID:Effect of a new amino acid solution on nutritional status and nitrogen metabolism in rats with chronic renal failure undergoing hyperalimentation. 1068 9

Moderately low levels of dietary protein are associated with increased food intake and body fat. We propose that the generation of this feeding signal is dependent on the level of dietary protein relative to the protein requirement of the animal, that is, that protein-dependent feeding is maximized when the level of dietary protein is around the animal's protein requirement. One of the factors that affects an animal's protein requirement is age. We predict that young, growing animals are more responsive to a moderately low level of dietary protein than are mature animals. The feeding response to moderately low dietary protein (10% casein) was determined in young ( approximately 190 g) and more mature ( approximately 340 g) Sprague-Dawley rats for 12 days. As an index of amino acid deamination, serum urea nitrogen concentrations were determined, as was the in vitro release of neuropeptide Y (NPY) from hypothalamic tissue containing the paraventricular nucleus. Young rats were more responsive to the feeding effects of moderately low dietary protein than mature animals. In young rats, cumulative food intake was inversely correlated with serum urea nitrogen concentration. No correlation was found in mature animals. Although the amount of NPY remaining in hypothalamic tissue after incubation was significantly greater (p = 0.04) in young rats fed 10% casein as compared with rats fed the standard 20% casein diet, no dietary difference in K(+)-stimulated NPY release was observed. We hypothesize that the signal for low-protein-induced hyperphagia is a reduction in a compound whose production is coupled to the level of amino acid deamination in the brain.
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PMID:Effects of age on the feeding response to moderately low dietary protein in rats. 1076 97

The study population in this report by Lin et al. was ob/ob mice that have an inherited genetic deficiency of the appetite-suppressing hormone leptin. These mice develop hyperinsulinemia, insulin resistance, and fatty livers. Compared with their lean littermates and wild-type C57BL-6 mice, ob/ob mice have hepatomegaly. In this study, the authors compared three different groups of adult mice (aged 8-10 wk), including male ob/ob C57BL-6 mice, their lean littermates, and wild-type C57BL-6 mice of the same age and sex. The primary purpose of this study was to test the efficacy of metformin for treatment of fatty liver disease in obese, ob/ob mice that develop hyperinsulinemia or insulin resistance and fatty livers. Metformin therapy was found to eliminate fatty liver disease in this model. The potential mechanisms of the action of metformin were the inhibition of hepatic tumor necrosis factor (TNF)alpha and several TNF-inducible responses, which are likely to promote hepatic steatosis and necrosis. In these experiments, ob/ob mice were divided into three treatment groups. Group 1 consisted of eight mice that were treated with metformin and permitted to consume a nutritiously replete liquid mouse diet ad libitum. Mice in group 2 (n = 8) did not receive metformin but were pair-fed the same volume of liquid diet that the mice in the metformin-treated group had consumed on the previous day. Obese ob/ob mice in group 3 (n = 4) and lean mice received no metformin, as with the mice in group 2, but were permitted to consume the liquid diet ad libitum. Liquid diet was given to facilitate accurate daily comparison of food intake among the various treatment groups. All mice were weighed at the beginning of the study and weekly thereafter until killed and then sera, fat, and liver tissues were collected. Tissues were either fixed in buffered formalin and processed from the deceased mice for histology or snap frozen in liquid nitrogen and stored until RNA and proteins were isolated. The feeding protocol was repeated with a second group of 18 ob/ob mice. After 4 wk, hepatocytes were obtained by in situ liver perfusion with collagenase and assayed for cellular adenosine triphosphate (ATP) content. In each experiment, hepatocytes isolated from 3 mice from each treatment group were suspended in a medium and pooled for subsequent analysis to evaluate cell viability, determine the number of obtained cells, and to assay cellular ATP content. These experiments were repeated using another 3 mice from each treatment group, so that analysis of hepatocytes took place from six ob/ob mice in each feeding group.Hepatic steatosis was decreased significantly only in the metformin-treated group. The authors found that metformin's beneficial effect on the fatty liver disease of mice was not due to its ability to constrain hyperphagia, nor due to decreased caloric ingestion, because the daily caloric intakes of the metformin-treated mice and the pair-fed control mice were virtually identical. These caloric intakes were consistently approximately 20% less than that of another obese control group that was permitted to consume diet ad libitum. The authors also observed no significant effect of metformin on serum glucose concentration from fed, ob/ob mice. Metformin is known to reduce hyperinsulinemia by about 40% in both of these obese hyperinsulinemic and insulin-resistant rodent strains. In conclusion, Lin et al. documented that metformin improves fatty liver disease and reverses hepatomegaly, steatosis, and aminotransferase abnormalities in mice. In addition, the authors suggest that metformin might inhibit dieting-induced redistribution of lipid from the liver to adipose tissue depots. In summary, this study identifies a potential treatment for fatty liver disease in humans.
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PMID:Current biochemical studies of nonalcoholic fatty liver disease and nonalcoholic steatohepatitis suggest a new therapeutic approach. 1449 93

The 15N/14N signature of animal proteins is now commonly used to understand their physiology and quantify the flows of nutrient in trophic webs. These studies assume that animals are predictably 15N-enriched relative to their food, but the isotopic mechanism which accounts for this enrichment remains unknown. We developed a box model of the nitrogen isotope cycle in mammals in order to predict the 15N/14N ratios of body reservoirs as a function of time, N intake and body mass. Results of modeling show that a combination of kinetic isotope fractionation during the N transfer between amines and equilibrium fractionation related to the reversible conversion of N-amine into ammonia is required to account for the well-established approximately 4 per thousand 15N-enrichment of body proteins relative to the diet. This isotopic enrichment observed in proteins is due to the partial recycling of 15N-enriched urea and the urinary excretion of a fraction of the strongly 15N-depleted ammonia reservoir. For a given body mass and diet delta15N, the isotopic compositions are mainly controlled by the N intake. Increase of the urea turnover combined with a decrease of the N intake lead to calculate a delta15N increase of the proteins, in agreement with the observed increase of collagen delta15N of herbivorous animals with aridity. We further show that the low delta15N collagen values of cave bears cannot be attributed to the dormancy periods as it is commonly thought, but inversely to the hyperphagia behavior. This model highlights the need for experimental investigations performed with large mammals in order to improve our understanding of natural variations of delta15N collagen.
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PMID:Box-modeling of 15N/14N in mammals. 1632 53

Diabetic ketoacidosis is characterized by a serum glucose level greater than 250 mg per dL, a pH less than 7.3, a serum bicarbonate level less than 18 mEq per L, an elevated serum ketone level, and dehydration. Insulin deficiency is the main precipitating factor. Diabetic ketoacidosis can occur in persons of all ages, with 14 percent of cases occurring in persons older than 70 years, 23 percent in persons 51 to 70 years of age, 27 percent in persons 30 to 50 years of age, and 36 percent in persons younger than 30 years. The case fatality rate is 1 to 5 percent. About one-third of all cases are in persons without a history of diabetes mellitus. Common symptoms include polyuria with polydipsia (98 percent), weight loss (81 percent), fatigue (62 percent), dyspnea (57 percent), vomiting (46 percent), preceding febrile illness (40 percent), abdominal pain (32 percent), and polyphagia (23 percent). Measurement of A1C, blood urea nitrogen, creatinine, serum glucose, electrolytes, pH, and serum ketones; complete blood count; urinalysis; electrocardiography; and calculation of anion gap and osmolar gap can differentiate diabetic ketoacidosis from hyperosmolar hyperglycemic state, gastroenteritis, starvation ketosis, and other metabolic syndromes, and can assist in diagnosing comorbid conditions. Appropriate treatment includes administering intravenous fluids and insulin, and monitoring glucose and electrolyte levels. Cerebral edema is a rare but severe complication that occurs predominantly in children. Physicians should recognize the signs of diabetic ketoacidosis for prompt diagnosis, and identify early symptoms to prevent it. Patient education should include information on how to adjust insulin during times of illness and how to monitor glucose and ketone levels, as well as information on the importance of medication compliance.
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PMID:Diabetic ketoacidosis: evaluation and treatment. 2354 50

Development and characterization of animal models of depression are essential for fully understanding the pathogenesis of depression in humans. We made and analyzed a mouse model exhibiting social deficit and hyperphagia-like behavior using a subchronic and mild social defeat stress (sCSDS) paradigm. The body weight, food and water intake of mice were monitored during a test period, and their behaviors and serum components were analyzed at two stages: immediately after the sCSDS period and 1 month after the sCSDS. The body weight and food intake of defeated mice were significantly higher than control mice at the sCSDS period, and these differences were sustained until 1 month after the sCSDS, whereas the water intake of defeated mice was significantly higher than control mice for the period of sCSDS only. Behavioral analyses revealed that the defeated mice exhibit significant social aversion to unfamiliar mice in a social interaction test and a trend of anxiety-like behavior in an elevated-plus maze test. Possibly due to polydipsia-like symptoms, defeated mice had significantly lower levels of albumin and blood urea nitrogen than control mice immediately after the sCSDS period but not at 1 month after sCSDS. The present study revealed that our sCSDS mice keep much more water in their body than control mice. This study reports the first step toward an understanding of the mechanisms of stress-induced overhydration, over-eating and resultant weight gain.
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PMID:Subchronic and mild social defeat stress accelerates food intake and body weight gain with polydipsia-like features in mice. 2487 70


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