Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

A study was designed to investigate the hypoglycaemia of severe kwashiorkor. The findings of significant stores of hepatic glycogen suggests that glycogenolysis was impaired. Plasma glucagon levels were relatively low, and it is suggested that this might be secondary to either a pancreatic alpha-cell defect, or inadequate sympathetic stimulation.
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PMID:Hypoglycaemia associated with severe kwashiorkor. 97 62

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