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)

New concepts concerning the pathogenesis and therapy of diabetic ketoacidosis are reviewed. The regulation of ketogenesis by intrahepatic enzymic processes and the roles of insulin deficiency or glucagon or other counterregulatory hormone excess are summarized. Major emphasis is placed on an analysis of the use of low-dose insulin regimens for the treatment of ketoacidosis. Most patients with diabetic ketoacidosis will respond to low-dose, hourly, intravenous or intramuscular regular insulin. Low doses of insulin are as effective as high doses and have fewer associated complications of hypoglycemia and hypokalemia. Phosphorus deficiency is common in diabetic ketoacidosis and hypophosphatemia usually becomes manifest within 4 to 12 h of institution of therapy. Phosphorus supplementation is now generally recommended to replete erythrocyte 2,3-diphosphoglycerate and improve oxygen delivery to tissues. Coexistent and biochemically significant lactic acidosis is a relatively infrequent complication of diabetic ketoacidosis and when present is usually due to underlying disorders associated with poor tissue perfusion.
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PMID:Diabetic ketoacidosis: new concepts and trends in pathogenesis and treatment. 41 52

Spontaneous fasting hypoglycemia developed in four nondiabetic patients with end-stage renal failure. All were undergoing long-term maintenance hemodialysis and three patients were anephric. Hypoglycemia was generally accompanied by severe metabolic acidosis and, in three patients, lactic acidemia. Abnormalities of hepatic structure and/or function were present in three patients. In one patient, hypoglycemia was refractory to exogenous glucagon, failed to respond to alanine, glycerol, or galactose, and was associated with suppressed plasma insulin and elevated plasma glucagon levels. Fasting hypoglycemia appeared to result from several mechanisms. In at least two patients, fasting hypoglycemia and lactic acidosis resulted from impaired hepatic gluconeogenesis in association with impaired or absent renal glucose production. Additionally, substrate limitation probably contributed to hypoglycemia in several patients.
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PMID:Spontaneous hypoglycemia in chronic renal failure. 68 26

Eighteen diabetic patients with lactic acidosis (L.A.) were analyzed for possible causal factors, metabolic changes, and efficacy of treatment. An antecedent phenformin therapy was performed in fifteen cases and was associated with renal insufficiency in ten cases and liver disease in eight cases. Tissular anoxia of primary hemodynamic or respiratory origin was absent in all cases. The severe metabolic acidosis (pH m.93 +/- 0,03; HCO3-= 6 +/- 1 MM; PaCO2 = 18 +/- 2 MM. Hg) and hyperlactatemia (14.2 +/- 0.3 mM) were associated with high lactate/pyruvate ration (70 +/- 22). High alanine levels (up to 4.6 mM) were measured in some of these patients. High beta-hydroxybutrate levels were sometimes measured (up to 7.6 mM), and substantial amounts of acetoacetate were also detected in twelve cases. Glucagon level was always increased (1,050 +/- 240 pg./ml.), and insulin/glucagon ratio was low. Cortisol (49 +/- 10 mug./100 ml.) and HGH (10.8 +/- 0.6 ng./ml.) were also elevated. Increased plasma levels of phenformin were measured in five L.A. diabetic subjects (50 +/- 5 mug./ml.) by comparison with other phenformin-treated diabetic subjects. The specificity of the assay was investigated, and phenformin metabolites were characterized by thin-layer chromatography. Por the treatment of L.A., adjunction of dialysis and furosemide improved the efficacy of early and massive sodium bicarbonate infusion. It is suggested that accumulation of phenformin via renal insufficiency plays a determinant role in causing L.A. through an impairment of lactate metabolism in the liver. An accelerated epuration of the drug may be helpful in therapy of L.A. Phenformin treatment should be avoided in case of renal and/or liver insufficiency.
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PMID:Phenformin-induced lactic acidosis in diabetic patients. 80 37

Two weeks after partial resection of the small intestine for an intra-abdominal stenosing centroblastic non-Hodgkin lymphoma, a 65-year-old man began to experience recurrent attacks of hypoglycaemia (down to 30 mg/dl) together with lactic acidosis (lactate 5.13 mmol/l), tachycardia and sensations of heat. Very high parenteral glucose input (up to 750 g/day) was necessary to maintain normal blood sugar levels. There was close correlation between the level of glucose consumption and the degree of lactic acidosis. After chemotherapy the abnormalities improved, but recurred as the neoplasm proliferated once more. An endocrine mechanism for the hypoglycaemic attacks was excluded by the low serum concentrations of insulin and of "insulin-like growth factors" I and II and by the fact that the levels of glucagon, glucocorticoids, growth hormone and thyroid hormone were within the normal ranges. There were pleural and peritoneal effusions containing large numbers of tumour cells. Investigated in vitro, the fluids showed a decline in glucose and a rise in lactate concentration. Studies with an artificial pancreas also showed that glucose utilization rate in vivo was increased to four times the normal and that it could be raised still further by insulin stimulation. These findings provide evidence of direct consumption of glucose by the tumour cells in the form of abnormally increased anaerobic glycolysis.
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PMID:[Recurrent hypoglycemia and lactate acidosis in non-Hodgkin's lymphoma]. 189 54

The present study was performed to determine whether alterations in fuel reserves or energy substrate utilization might explain the performance decrements that occur in bacterial infections. Male Fisher-Dunning rats were studied at 24, 48, and 72 h after inoculation with Streptococcus pneumoniae. Rats were either sedentary or subjected to a 2-h swimming session at these three time points (N = 10 in each group). A more than 60% reduction (P less than 0.01) in performance capacity was observed on day 3 of infection compared with that in noninfected controls. This infection in the rat is characterized by fever (P less than 0.01), depression of plasma zinc (P less than 0.01) and free fatty acid (FFA) levels (P less than 0.01), inhibition of the two- to threefold increase in fasting ketonemia, and a decreased (NS) insulin:glucagon ratio, indicating a catabolic state. Glycogen stores were reduced in the heart (47%), liver (43%), and skeletal muscles (39%) but not in the carcass. Superimposed exercise resulted in a further reduction but not depletion of liver, muscle, and carcass glycogen stores, a less pronounced lactic acid accumulation, and a lower oxygen debt. However, plasma FFA and ketone body levels were still maintained or even elevated, suggesting that fat is supplied as fuel during swimming exercise in this infection. Thus, results indicate that unavailability of energy substrates or lactacidosis is not limiting for performance capacity during this severe infection.
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PMID:Metabolic responses to swimming exercise in Streptococcus pneumoniae infected rats. 205 98

Seizures are a documented complication to cerebral ischemia. After 10 min of forebrain ischemia in rats, preischemic hyperglycemia invariably leads to severe, most often fatal epileptic attacks. This outcome is related to the exaggerated lactic acidosis, which has been suggested as a possible contributor to severe membrane changes and widespread edema. To find out if circulating hormones or plasma energy substrates modulate this additive damage caused by the hyperglycemia, plasma concentrations of of corticosterone, epinephrine, norepinephrine, dopamine, glucagon, insulin, glucose, free fatty acids (FFA), 3-hydroxybutyrate, and acetoacetate were measured before and in the early recirculation period after 15 min of forebrain ischemia in the rat. Plasma corticosterone levels did not differ between the normo- and hyperglycemic groups. Although not significantly different from control, the catecholamine levels showed a tendency to be higher in the hyperglycemic groups. Therefore, because catecholamines have been reported to have a protective effect during ischemia the present result cannot explain why hyperglycemia aggravates the ischemic damage. Insulin levels seemed to increase during ischemia but not significantly. Levels quickly returned to normal after 30 min of recirculation. FFA concentrations were reduced after the induction of ischemia and appeared lower in all hyperglycemic groups. The level of one of the ketone bodies, 3-hydroxybutyrate, showed a significant decrease in hyperglycemic ischemia in all groups compared with normoglycemic ischemia. The same tendency was seen for acetoacetate. Results are compatible with a protective role of ketone bodies in ischemia. It is concluded that among the hormones and substrates studied only the ketone body concentrations qualify as a modulator of the exaggerated brain damage after ischemia in hyperglycemic subjects.
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PMID:Ischemia in normoglycemic and hyperglycemic rats: plasma energy substrates and hormones. 211 Apr 23

A 31-year-old male patient with type Ia glycogen storage disease was admitted to our department complaining of general fatigue and right hypochondriac pain. He exhibited massive hepatomegaly with systemic hypoglycemia, lactic acidosis, hyperuricemia, hyperpyruvatemia and hyperlipemia. The failure of blood glucose levels to increase after a glucagon loading test, and a reduced lactate level on glucose tolerance test were also observed. Various imaging techniques suggested hepatic adenoma with hemorrhage in the tumor, which was confirmed histologically. There was a complete absence of glucose 6-phosphatase activity, as determined by an enzyme assay on resected liver specimens, which proved the case to be type Ia glycogen storage disease. We also reviewed all previously reported cases of hepatic tumor and glycogen storage diseases. We conclude that, since hepatic adenoma is not rare in this disease, and is complicated by hemorrhage, rupture and malignancy, careful follow-ups are necessary.
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PMID:A case of type Ia glycogen storage disease complicated by hepatic adenoma. 217 Feb 59

The intrinsic processes involved in the initiation and arrest of seizures are not completely understood. Cortical and cerebellar inhibitory mechanisms, accumulation of metabolic products, and glial uptake of extracellular potassium (K+o), anions, and released neurotransmitters are all important processes that limit focal firing and terminate a seizure once it has been initiated. Of these, the intrinsic cortical inhibitory mechanisms--i.e., recurrent and surround inhibition--appear to be the most important. Active cation and anion transport processes are two metabolic events that have yet to be elucidated but clearly could be involved in terminating a seizure discharge. For example, without an active mechanism to transport chloride, opening of the chloride channel by the inhibitory transmitter GABA would not result in increased chloride permeability. The transient hypoxia and hypercapnia and lactic acidosis that follows a severe tonic-clonic seizure produces a mixed systemic metabolic and respiratory acidosis. In experimental animals, the hypercapnia that results is sufficient to block seizure discharges. Increasing the CO2 concentration significantly reduces the extension to flexion (E/F) ratio of mice given maximal electroshock seizures (MES) and increases the time required for 50% of the animals to recover sufficiently from a first MES to be able to have another MES. The decreased E/F ratio and the increased recovery time (RT50) are both indicative of a decrease in seizure activity. Since the extent to which CO2 is allowed to accumulate in the brain is regulated by the glial specific enzyme carbonic anhydrase (CA), it follows that the glial cell has an integral role in the mechanisms involved in arresting seizure activity. In contrast, hypoxia increased the E/F ratio and decreased the RT50, evidence that seizure activity was enhanced. Another metabolic factor affecting duration of seizure activity, susceptibility to seizures, and recovery from seizures is glucose. Recovery from seizures depends in part on an adequate supply of this energy source. An inverse correlation (R = 0.95) between RT50 and blood sugar was found when the blood sugar was altered experimentally by treatments that altered the endocrine status (pancreatectomy, treatment with alloxan, cortisol, insulin, glucagon, and dextrose). Since glial cells contain (as glycogen) the small amount of glucose present in the brain, they probably hasten the ability of the brain to recover normal function following a seizure.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Role of glial cation and anion transport mechanisms in etiology and arrest of seizures. 370 23

An 8-month-old female, maintained on breast feeding for 6 months, experienced numerous attacks of hyperventilation when weaned to baby food and was admitted with severe lactic acidosis (20 mM) and hypoglycemia. Physical examination was negative except for hepatomegaly. Fasting (18 hr) after stabilization on a high carbohydrate diet resulted in hypoglycemia (plasma glucose 40 mg/100 ml), lactic acidosis (6-10 mM), and a rise in plasma alanine. Glucagon produced a glycemic response after 6 hr, but not after 18 hr fasting. Intravenous galactose increased plasma glucose (Delta 45 mg/100 ml) but intravenous fructose, glycerol, and alanine caused a 40-50% fall in plasma glucose and a significant rise in lactate (Delta 3-4 mM). Liver biopsy showed fatty infiltration. Liver slices incubated with galactose, lactate, fructose, alanine, or glycerol converted only galactose to glucose. Hepatic glycolytic intermediates were increased below the level of fructose-1,6-diphosphate and decreased above. Hepatic phosphorylase, glucose-6-phosphatase, amylo-1,6-glucosidase, phosphofructokinase, fructose-1-phosphate aldolase, and fructose-1,6-diphosphate aldolase levels were normal, but no fructose-1,6-diphosphatase (FDPase) activity was detected. Further studies on the liver homogenate of this patient revealed the presence of an acid-precipitable activator of FDPase. Normal plasma glucose and lactate levels were maintained on an 800 cal diet of 66% carbohydrate (sucrose and fructose excluded). 5% protein, and 20% fat. When carbohydrate was reduced to 35% and protein or fat increased to 23 and 53% respectively, lactic acidosis and hypoglycemia recurred. These studies show that a deficiency of FDPase produced infantile lactic acidosis and hypoglycemia and can be controlled by an appropriate diet.
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PMID:Hepatic fructose-1,6-diphosphatase deficiency. A cause of lactic acidosis and hypoglycemia in infancy. 434 Oct 15

1. GSD-I is described in a child with partial deficiency of hepatic glucose-6-phosphatase. 2. Growth retardation and hepatosplenomegaly were major clinical features. 3. Hyperlipidaemia, lactic acidaemia, hyperuricaemia and reduced uric acid clearance were major biochemical findings. 4. Although the glucose response to glucagon and galactose was impaired, there was a striking absence of hypoglycaemia which may be attributable to residual catalytic activity of the enzyme. 5. Preliminary studies of the crude liver enzyme showed it to have a normal pH inactivation profile and apparent Km with a reduced Vmax. 6. No evidence of increased PP-ribose-P availability in fresh liver tissue was detected. 7. Continuous glucose feeding resulted in accelerated growth without complete correction of lactic acidosis or hyperuricaemia. 8. GSD-I with partial deficiency of hepatic glucose-6-phosphatase should be considered in patients with gout or hyperuricaemia associated with hypertriglyceridaemia and lactic acidaemia even in the absence of hypoglycaemia.
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PMID:Clinical and enzymological studies in a child with type I glycogen storage disease associated with partial deficiency of hepatic glucose-6-phosphatase. 615 47


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