Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
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Homeostasis of the internal environment in mammals is accomplished by a series of feedback mechanisms in a variety of tissues. Homeostasis of cell structure and function during marked changes in the environment is equally important. Both types of homeostasis are dependent on adjustments in endocrine function and changes in enzyme activity. In some instances the intracellular servomechanisms required for homeostasis match in vigor and range the perturbations of the external environment. The regulation of cell metabolism is accomplished by enzymatic, membranous and genetic mechanisms. Most peptide hormones act by combining with a specific receptor in the membrane of sensitive cells, which activates adenyl cyclase to produce cyclic AMP which in turn has selective second messenger functions. Insulin and somatotropin appear to be exceptions and may act via cyclic GMP. Steroid hormones, on the other hand, pass through the cell membrane and combine with a specific receptor protein in the cytoplasm of sensitive cells. This receptor then serves as a transport system for movement of the hormone to the nucleus where it stimulates specific protein synthesis. Nutritional effects on enzyme synthesis are partially direct and partially mediated by the endocrine system. Trace nutrients, especially the fat-soluble vitamins, appear to act directly to modify specific protein syntheses, whereas the bulkier constituents of the diet (carbohydrate, fat protein) exert their effects principally through altered rates of secretion of insulin, glucagon, and the glucocortioids. Protein-calorie malnutrition is the result of a massive assault on homeostatic and adaptive mechanisms designed to conserve nutrients and preserve life. The pathogenesis of marasmus and kwashiorkor is discussed in the light of these adaptive mechanisms.
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PMID:Introductory remarks: nutrient, hormone, enzyme interactions. 80 21

The prevalence of diabetes due to chronic pancreatitis would appear to be increasing. In western countries this is associated with the known increase in alcohol consumption and AIP. Malnutrition may be etiologic in tropical areas. The incidence of diabetes in chronic pancreatitis is dependent on a number of factors. It is more common in alcohol-induced pancreatitis, rarely occurs after the first attack but tends to increase with time and rises markedly in calcific pancreatitis. Abnormal glucose tolerance occurred in 91% of patients with calcific pancreatitis and 70% of patients with noncalific AIP in our follow up of five to 12 years. This stresses the importance of serial regular glucose tolerance tests in these patients (Table I). The insulin-reserve is severely depleted in most patients who do not yet demonstrate abnormal glucose tolerance, indicating that pancreatitis regularly affects the islets and that nearly all patients are potential diabetics. The beta cells appear to respond better to oral glucose, glucagon or secretin than to i.v. glucose suggesting a selective glucose receptor loss or block to hyperglycemia in chronic pancreatitis. The alpha cells seem to be more resistant to the effects of chronic pancreatitis but true hypoglucagonemia was found in 16% of patients. In addition, stimulated growth hormone secretion may be deficient in pancreatic diabetes. These last two factors, among others, may be responsible for the protracted and even fatal hypoglycemia to which some patients with AIP on insulin therapy are liable. The danger of drug-induced hypoglycemia, coupled with the infrequency of vasculopathy, retinopathy and nephropathy in pancreatic diabetes has induced us to keep these patients hyperglycemic and glycosuric rather than in a sugar-free state, as long as symptoms are contained. Recurrent abdominal pain, marked weight loss and associated steatorrhea often raise special problems in the management of the pancreatic diabetic.
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PMID:Clinical and hormonal aspects of pancreatic diabetes. 80 21

The salient information regarding the effects of uremia and dialysis on each of the metabolic fuels and hormones presented in the preceding sections is summarized in three tables. Tables 1 and 2 provide data on plasma levels, metabolism, dialysance, and literature references for each substance. Table 3 organizes the data according to the general mechanisms by which uremia and chronic dialysis may affect biological substances. Together these tables provide a reasonably complete summary of the information presently available. The pathophysiology of the uremic syndrome is still incompletely understood. The numerous metabolic and endocrine alterations associated with uremia and chronic dialytic therapy underscore the complexity of the problem and identify several specific areas for future research. One which deserves emphasis is the poolic and endocrine abnormalities found in uremia. A recent review by Chantler and Holliday (63) stressed in the importance of protein-calorie deficiency in the pathogensis of growth retardation and disturbed hormonal metabolism in children with chronic renal failure. The importance of this factor in adult patients with chronic uremia has been less well appreciated. However, striking similarities exist between the metabolic and endocrine abnormalities found in protein-calorie malnutrition and those found in uremia. These include, for example, altered albumin and amino acid metabolism, decreased levels of serum transferrin, peripheral insulin resistance and carbohydrate intolerance, elevated levels of glucagon, cortisol and growth hormone, and possibly diminished secretion of thyrotropin and thyroxine. Although not absolutely identical, the similarities between these two clinical syndromes suggest intriguing possible approaches to a better understanding of the pathophysiology of the uremic syndrome and its treatment.
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PMID:Endocrinology and metabolism in uremia and dialysis: a clinical review. 80 79

Chronic pancreatitis is defined by a persistent destruction of the pancreatic parenchyma replaced by fibrosis. The lesions generally start in the exocrine gland, islets being attacked later in the fibrosis. The two most frequent forms are: 1. Chronic calcifying pancreatitis which is a pancreatic lithiasis responsible for more than 95% of chronic pancreatitis. In its most frequent form, calculi are built up of more than 98% calcium salts together with fibres of a degraded residue of lithostathine, a secretory protein. This disease is related (i) in most countries to alcohol, protein, fat and tobacco and (ii) in certain tropical countries to malnutrition (low-fat, low-protein diet) for some generations. A causative role for cassava and kwashiorkor is improbable. The mechanism of calcium precipitation is partly explained by the calcium-saturation of pancreatic juice and the decreased biosynthesis of lithostathine S, the secretory protein preventing crystallization. As a rule, diabetes (and steatorrhoea) appear after a clinical evolution characterized by recurrent attacks of upper abdominal pain, generally lasting some days with transiently increased concentrations of pancreatic enzymes in serum. When diabetes appears, pain frequently disappears. Complications are mostly observed in the first 10 years of clinical evolution. 2. Obstructive pancreatitis is due to an obstacle (tumours, scars) in the pancreatic duct. It is rarely a cause of diabetes. Diabetes due to chronic pancreatitis is characterized by the low incidence of ketosis and the high incidence of insulin-induced hypoglycaemia. Patients are generally thin. Serum insulin levels, either basal or stimulated, are decreased. Glucagon is less affected. Angiopathies and retinopathies are less frequent than in non-insulin-dependent diabetes. Neural complications are fairly frequent. The diagnosis is generally easy because diabetes appears at a late stage of the disease. The treatment generally requires insulin.
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PMID:Chronic pancreatitis and diabetes. 144 67

Immunological implications are important in every surgical operation, specially when it is necessary to remove the spleen. She plays an important role in immunological aspecific (filter, phagocytosis) and specific processes (production of IgM and regulation of T- and B-lymphocytic system). Splenectomy causes an immunodeficiency with frequent post-operative complications (the most important is OPSI). Each operated patient is considered generically immunodeficient because surgical trauma and anesthesiologic practice are at the base of immunological alterations (biological barriers, aspecific immunity, A.P.P., complement, specific immunity, NK cells). It's indispensable to know pathological situations that make "critical" the immunological state: caloric-proteic malnutrition, elderly (greater than 70 years old), immunosuppressive therapy, sepsis, shock, neoplasms. I. e.: a patient about seventy years old presents a reduced endocrine secretion of thymic hormone and, probably, a low synthesis of immunoglobulins. Besides the corticosteroids modify the answer of T-lymphocytes and NK cells. Sepsis induces metabolic and immunological alterations after early activation of humoral mediators, modified quantity and life of A.P.P., activation of complement, inhibition of cell-mediate immunity, modification of number and activity of haematic lymphocytes. Trauma induces a hypersecretion of corticosteroid, adrenalin, noradrenaline, glucagon with consequent hypercatabolism that causes malnutrition. The hormonal hypersecretion is a determining factor of reduced phagocytic activity (inhibited migration of neutrophils and monocytes), quantitative and qualitative alterations of complement, deficit of T-cells, hyporeactivity to skin test, depressed answer of antibodies to bacterial and viral antigens. Progressive neoplasms are characterized by modification of T-lymphocytes number, depressed macrophagic activity, hyporeactivity to skin tests.
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PMID:[Immunological implications of surgical intervention in critical and noncritical patients]. 175 43

Cases of malnutrition-related diabetes mellitus conforming to the description of the protein deficient pancreatic diabetes type in Ethiopian patients were compared with Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetic. Fourteen of 39 malnutrition-related diabetes mellitus patients had fat malabsorption compared with only two of ten Type 1 diabetic patients and one of nine control subjects. Xylose absorption was normal favouring a pancreatic cause for the malabsorption. Plasma C-peptide during oral glucose tolerance test was significantly lower than that in Type 2 diabetic patients and normal control subjects (p less than 0.01 to 0.001) and was also consistently but not significantly higher than in Type 1 diabetic patients. Glucagon secretion patterns were similar in malnutrition-related and Type 1 diabetic patients. Of 23 new malnutrition-related diabetic patients treated with glibenclamide after nutritional rehabilitation and insulin treatment, only three responded, 14 were unresponsive but remained ketosis free for over eight days while another six developed ketoacidosis or significant ketonuria within two to six days during the trial. Sixteen unselected Type 1 diabetic patients who discontinued their insulin therapy all developed frank ketoacidosis after a mean of 5.5 days. The similarity of the malnutrition-related and Type 1 diabetes mellitus in age of onset, insulin requirement for diabetic control and appearance of ketosis-proneness in some cases, together with the similarity of C-peptide and glucagon secretion patterns suggest that the protein deficient pancreatic diabetes variant of malnutrition-related diabetes mellitus may be Type 1 diabetes mellitus modified by the background of malnutrition rather than an aetiologically separate entity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The clinical and hormonal (C-peptide and glucagon) profile and liability to ketoacidosis during nutritional rehabilitation in Ethiopian patients with malnutrition-related diabetes mellitus. 211

To determine the frequency and outcome of hypoglycemia during diarrhea in childhood, we screened 2003 consecutive patients less than 15 years of age who were admitted to a diarrhea treatment center in Dhaka, Bangladesh. Hypoglycemia, defined as a blood glucose concentration less than 2.2 mmol per liter, was found in 91 patients (4.5 percent), 39 (42.9 percent) of whom died. We also measured the plasma concentrations of glucoregulatory hormones and gluconeogenetic substrates in 46 of the patients with hypoglycemia who were 2 to 15 years old and in 25 normoglycemic patients matched with them for age and weight. The patients with hypoglycemia had had diarrhea for less time than the normoglycemic patients (median, 12 vs. 72 hours; P less than 0.05), and their last feeding had been 18 hours before admission, as compared with 9 hours for the normoglycemic patients (P less than 0.05). The groups were similar in terms of nutritional status, the proportion of patients who had fever, and the types of pathogens recovered from stool samples. The plasma C-peptide concentrations were low (less than 0.30 nmol per liter) in all the hypoglycemic patients. As compared with the normoglycemic patients, the patients with hypoglycemia had elevated median plasma concentrations of glucagon (44 vs. 11 pmol per liter; P = 0.001), epinephrine (3400 vs. 1500 pmol per liter; P = 0.012), norepinephrine (7500 vs. 2900 pmol per liter; P = 0.002), and lactate (3.5 vs. 2.1 mmol per liter; P = 0.020) and similar alanine and beta-hydroxybutyrate concentrations. Eighteen hypoglycemic patients with severe malnutrition had been ill longer than 26 better-nourished patients with hypoglycemia (median duration of illness, 18 vs. 10 hours; P = 0.023) and had lower median plasma concentrations of lactate (1.9 vs. 3.9 mmol per liter; P = 0.021) and alanine (173 vs. 293 micromol per liter; P = 0.040). We conclude that hypoglycemia is a major cause of death in association with diarrhea. Because the glucose counterregulatory hormones were appropriately elevated in the children with diarrhea and hypoglycemia, whereas the gluconeogenetic substrates were inappropriately low, we further conclude that the hypoglycemia observed in such patients is most often due to the failure of gluconeogenesis.
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PMID:Hypoglycemia during diarrhea in childhood. Prevalence, pathophysiology, and outcome. 232 37

Hypoglycemia associated with renal failure is more common than generally thought. Its occurrence is often a marker of multisystem failure and has an ominous prognostic implication. Its pathogenesis is frequently complex and involves one or several mechanisms. In the evaluation of uremic hypoglycemia, the first step should be the exclusion of obvious causes such as insulin, oral hypoglycemic agent therapy, and the use of drugs known to cause hypoglycemia. Propranolol, salicylates, and disopyramide are among the most commonly implicated agents. Additional triggering events are alcohol consumption, sepsis, chronic malnutrition, acute caloric deprivation, concomitant liver disease, congestive heart failure, and an associated endocrine deficiency. When no obvious cause can be demonstrated, the hypoglycemia is referred to as spontaneous. Spontaneous uremic hypoglycemia has been attributed to deficiency of precursors of gluconeogenesis, that is, alanine, deficient gluconeogenesis, impaired glycogenolysis, diminished renal gluconeogenesis and impaired renal insulin degradation and clearance, poor nutrition, and, in a few cases, deficiency in an immediate counterregulatory hormone such as catecholamine and glucagon. However, the mechanism(s) seems to differ from one patient to the other. Dialysis also predisposes to hypoglycemia in uremia, possibly because of the chronic state of malnutrition. Postdialysis hypoglycemia is secondary to glucose-induced hyperinsulinemia, which is caused by the high glucose content in the dialysate. In uremic hypoglycemia, neuroglycopenic manifestations predominate because of frequent autonomic nervous system dysfunction and lack of catecholamine release in response to hypoglycemia. Its severity and duration are variable. Hypoglycemia should be suspected in any patient with renal failure who exhibits any change in mental or neurologic status. Detection of hypoglycemia should rely on frequent and careful glucose determinations in any patient with uremia.
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PMID:Hypoglycemia associated with renal failure. 264 22

Blood glucose, plasma insulin and glucagon, as well as pancreatic insulin, glucagon and somatostatin contents, were measured in control (C group, 18% casein), deprived (D group, 5% casein) and pair-fed (PF) rats at seven intervals during 23 wk after weaning (wk 0). In C rats, plasma and pancreatic insulin showed parallel variations, in D rats, plasma insulin increased normally until wk 3 after weaning, dropped from wk 3 to 8 and was higher in wk 16 and 23 than in wk 8, while pancreatic insulin increased linearly after a significant drop between wk 0 and 1. Insulin variations in D rats were related to protein deficiency until wk 5, but only to energy deficiency thereafter. Circulating and pancreatic glucagon dropped identically for the three groups until wk 5: its role in adaptation to malnutrition is quite irrelevant, although a dysregulation of its secretion was noted. Protein-energy malnutrition induced an increase of pancreatic somatostatin content that was due to the energy deficiency. On the basis of the insulin-to-glucagon ratio, three phases of adaptation to protein-energy malnutrition appeared. From wk 0 to 3, the metabolic priority was growth, whereas glucose homeostasis was secondary, accounting for the early hypoglycemia. From wk 3 to 8 survival was the main priority. After wk 8, the various biochemical parameters stabilized, and growth was parallel to that of normal animals. Protein-energy malnutrition was responsible for a dissociated adaptation of pancreatic hormones.
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PMID:Progressive adaptation of the endocrine pancreas during long-term protein deficiency in rats: effects on blood glucose homeostasis and on pancreatic insulin, glucagon and somatostatin concentrations. 286 38

Food was restricted in pregnant and nursing rats in order to evaluate the effect of malnutrition on insulin and glucagon metabolism in fetal and suckling rats. Food restriction of the mothers induced a loss of body and liver weights in their offspring, which was more pronounced in suckling than in fetal rats. A significant decrease of circulating insulin and glucagon levels in fetal and suckling rats from food restricted mothers (FRM) was also observed. In liver membranes insulin binding was higher in control, fetal and suckling rats than in adult animals, but maternal food restriction decreased insulin binding to liver membranes of suckling rats, and no changes between control and fetuses from FRM were observed. By contrast, glucagon binding was higher in adult than in younger control animals; however maternal food restriction had no effect on glucagon binding to liver membranes of fetal rats, although they produced an increase in 10 day-old suckling rats. The modifications in insulin and glucagon binding reflect changes in the number of receptors, but not in the affinity constants. The time courses of insulin and glucagon association to liver membranes were unaffected by the development or by the nutritional status of the animals. Degradation of insulin and glucagon by liver membranes was significantly lower in young rats and in rats from FRM, but this does not seem to be responsible for the differences observed in binding. No significant differences in the degradation of insulin and glucagon receptors between different groups of liver membranes were found.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of maternal food restriction on circulating insulin and glucagon levels and on liver insulin and glucagon binding sites of fetal and suckling rats. 302 80


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