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Query: UMLS:C0243026 (sepsis)
 52,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The plasma concentration of various catabolic hormones, including glucagon and catecholamines, is elevated in sepsis. Furthermore, the infusion of these hormones into control animals increases the rate of glucose production. Previous studies by our laboratory have demonstrated that adrenergic blockade alone is not able to reverse or prevent the sepsis-induced increase in glucose metabolism. Therefore, the purpose of the present study was to determine whether the sepsis-induced hyperglucagonemia was important to maintain the elevation in glucose metabolism. Hypermetabolic sepsis was produced in chronically catheterized conscious rats by repeated subcutaneous injections of Escherichia coli. Glucose kinetics, assessed by the constant i.v. infusion of [6-3H]- and [U-14C]-glucose, were determined in septic and nonseptic rats prior to and for 3-4 hr after the infusion of somatostatin with or without insulin replacement. Sepsis increased the rate of glucose appearance (80%), recycling (276%), and metabolic clearance (88%), as well as the plasma lactate concentration (140%), compared to nonseptic rats. Lowering both the insulin and glucagon concentration with somatostatin did not attenuate the sepsis-induced increases in glucose metabolism. However, when the hyperglucagonemia was selectively reduced by replacing insulin, and euglycemia was maintained by a glucose infusion, the elevated rate of endogenous glucose production returned to levels not different from nonseptic animals. In contrast, the sepsis-induced elevation of glucose clearance was unaltered under these conditions. These results indicate that during hypermetabolic sepsis the elevated glucagon level is an important mediator of the enhanced rate of gluconeogenesis.
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PMID:Importance of hyperglucagonemia in eliciting the sepsis-induced increase in glucose production. 257 79

To assess the effect of sepsis on ketone body (KB) kinetics in humans, we measured in normal and septic subjects KB appearance rate (Ra) before (initial state) and during a rise of free fatty acids (FFA) level (intravenous infusion of a triglycerides emulsion). We studied normal subjects in postabsorptive state and septic patients when receiving an hypocaloric intravenous infusion of glucose and amino acids or 12 h after its interruption. When receiving glucose and amino acids infusion, septic patients had higher glucose and insulin levels than normal subjects, and despite lower FFA concentrations (255 +/- 44 vs. 480 +/- 51 mumol/l, P less than 0.05) comparable initial KB Ra (2.50 +/- 0.10 vs. 2.48 +/- 0.30 mumol.kg-1.min-1). Triglyceride infusion increased FFA to comparable values (septic 780 +/- 130, normal 730 +/- 45 mumol/l), but KB Ra rose in septic patients only to 3.7 +/- 1.1 instead of 7.7 +/- 1.1 mumol.kg-1.min-1 as in normal subjects (P less than 0.05). Somatostatin infusion decreased the hyperinsulinemia of septic patients but did not restore a normal ketogenesis. After interruption of nutriment infusion, septic patients had normal FFA levels and only mild hyperglycemia and hyperinsulinemia. Their initial KB Ra was not modified. However, their response of KB Ra (increase to 6.27 +/- 2.0 mumol.kg-1.min-1) to raised FFA levels (842 +/- 170 mumol/l) was comparable to the response of normal subjects. In conclusion, although septic patients receiving an hypocaloric parenteral nutrition had a depressed ketogenesis they were able to restore a normal ketogenic capacity after a short-time caloric deprivation. Glucose and/or insulin appears to have a major role in this modulation of hepatic ketogenesis.
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PMID:Regulation of ketone body flux in septic patients. 259 97

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

1. Sepsis induced by caecal ligation and puncture increased the rates of hepatic cholesterogenesis and fatty acid synthesis in vivo compared with sham-operated rats. These changes were accompanied by higher concentrations of lactate and pyruvate in blood and liver and an increase in plasma insulin. 2. The total activity of hydroxymethylglutaryl-coenzyme A (HMG-CoA) reductase (EC 1.1.1.88) in liver was increased by sepsis, but there was no significant change in the expressed activity. Short-term insulin deficiency (induced by mannoheptulose or streptozotocin) decreased the rates of cholesterogenesis and fatty acid synthesis in livers of septic rats but did not alter the expressed/total activity of HMG-CoA reductase. 3. It is concluded that the increased rate of hepatic cholesterogenesis in septic rats is in part a result of the higher plasma insulin, the hormone acting to maintain the total activity of HMG-CoA reductase and to stimulate a step before the formation of HMG-CoA. 4. These changes may contribute to the hypertriacylglycerolaemia associated with sepsis.
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PMID:Increased rates of hepatic cholesterogenesis and fatty acid synthesis in septic rats in vivo: evidence for the possible involvement of insulin. 264 66

The present study was performed to determine whether hypermetabolic sepsis alters peripheral and hepatic insulin sensitivity and/or responsiveness. Nonlethal sepsis was produced in chronically catheterized conscious rats by repeated subcutaneous injections of live Escherichia coli. Basal glucose metabolism was determined using a primed-constant infusion of [3-3H]glucose initiated 20 hr after the first injection of bacteria. Thereafter, in vivo insulin action was assessed using the euglycemic hyperinsulinemic clamp technique. Insulin was infused at various rates in separate groups of animals for 3 hr to produce steady-state insulin levels of approximately 60, 120, 400, 2,500, and 25,000 microU/ml, and euglycemia was maintained by varying the glucose infusion rate. The sepsis-induced hyperglucagonemia was not significantly altered by the infusion of insulin and glucose. In septic rats, the dose-response curve for the insulin-induced increment in glucose utilization was shifted downward and to the right. As a result, septic rats showed a twofold increase in the ED50 value (380 vs. 190 microU/ml) and a 50% reduction in the maximal responsiveness compared with control animals, indicating peripheral insulin resistance. Septic and nonseptic animals, however, had a similar reduction in the endogenous glucose production rate as the plasma insulin concentration was increased, suggesting that there was no hepatic insulin resistance. The plasma lactate concentration increased in a dose-dependent manner in both septic and nonseptic rats as the plasma insulin concentration was raised. However, the increment in steady-state lactate concentration was consistently higher (75-220%) in septic animals at each insulin infusion rate. These results indicate that nonlethal hypermetabolic sepsis in the rat is associated with peripheral insulin resistance.
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PMID:In vivo insulin resistance during nonlethal hypermetabolic sepsis. 266 Oct 48

Proteolysis is increased in sepsis, but it is not known whether myofibrillar and non-myofibrillar proteins are broken down in the same fashion, or respond to the same regulatory forces as in non-septic muscle. In this study, therefore, the effect of sepsis on total and myofibrillar protein breakdown in incubated rat extensor digitorum longus (EDL) and soleus (SOL) muscles was determined, and the response in vitro to different concentrations of insulin (10 to 10(5) microU/mL) of protein degradation was studied in incubated EDL muscles from control and septic rats. Sepsis was induced in rats weighing 40 to 60 g by cecal ligation and puncture (CLP). Control animals were sham operated. Sixteen hours after CLP or sham operation, intact EDL and SOL muscles were incubated for two hours in oxygenated Krebs-Henseleit bicarbonate buffer containing glucose (10 mmol/L) and cycloheximide (0.5 mmol/L), and total and myofibrillar protein breakdown was assessed from release into incubation medium of tyrosine and 3-methylhistidine (3-MH), respectively. Tyrosine and 3-MH were determined fluorometrically by high performance liquid chromatography (HPLC). Tissue levels of tyrosine and 3-MH remained stable both in control and septic muscles during incubation for two hours. The rate of tyrosine release was increased during sepsis by 58% (P less than .001) and 15% (NS) in EDL and SOL muscle, respectively. The corresponding figures for 3-MH were 103% (P less than .001) and 21% (NS). Tyrosine release was reduced by insulin at a concentration of 10(3) microU/mL in control muscle and at a concentration of 10(4) microU/mL in septic muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Total and myofibrillar protein breakdown in different types of rat skeletal muscle: effects of sepsis and regulation by insulin. 266 65

The effects of exogenous insulin on oxidation of glucose and fatty acid were investigated in septic (n = 20) and control rats (n = 20). Sepsis was induced by ligation and puncture of the caecum. The rats received intravenous nutrition with glucose as a non-protein calorie for 27 hours. Ten rats in each group received insulin intravenously at a rate of 0.64U/kg/hr during the last 6 hours of the intravenous nutrition, U-14C-glucose or 1-14C-linoleic acid at a dose of 1.563 microCi each was injected as a bolus at the 21st hour of the intravenous nutrition. Cumulative 14CO2 production was measured for 6 hours after the injection of the radioactive substrates. 14CO2 production from both glucose and linoleic acid was inhibited by the sepsis. 14CO2 production from glucose was accelerated by exogenous insulin in the control rats, while it was not accelerated in the septic rats. Exogenous insulin did not affect 14CO2 production from linoleic acid in both the control and the septic rats. These results indicate that, under the condition of sepsis, lowering blood sugar level with exogenous insulin does not refLect an increase in oxidation of glucose.
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PMID:[Effects of exogenous insulin on oxidation of glucose and fatty acid in septic rats]. 266 30

The present study examined whether sepsis exacerbates the diabetes-induced peripheral and hepatic insulin resistance. Vascular catheters were placed in diabetic (70 mg/kg streptozotocin, 4-wk duration) and nondiabetic rats, and sepsis was produced by subcutaneous injections of live Escherichia coli. Basal glucose metabolism was determined with the use of [3-3H]glucose initiated 18 h after the first injection of bacteria. Thereafter, in vivo insulin action was assessed with the use of the euglycemic hyperinsulinemic clamp technique. Sepsis in nondiabetic rats produced a 57% reduction in the maximal responsiveness for the insulin-induced increase in total glucose utilization compared with nondiabetic nonseptic animals. Diabetes alone decreased both insulin sensitivity and responsiveness. When the septic insult was superimposed on the diabetic condition, the maximum responsiveness was unchanged compared with non-septic diabetic rats, but the 50% maximally efficient dose was reduced from 817 to 190 microU/ml, suggesting an improvement in insulin sensitivity. Sepsis did not alter the insulin-induced suppression of hepatic glucose output in either nondiabetic or diabetic animals. Sepsis increased the plasma concentrations of epinephrine, norepinephrine, glucagon, and corticosterone in both nondiabetic and diabetic rats; however, the elevation in catecholamines and glucagon was 65 to 250% greater in the diabetic animals. These results indicate that hypermetabolic sepsis produces peripheral insulin resistance in nondiabetic rats but does not worsen the preexisting insulin resistance in diabetic animals, despite the higher prevailing blood levels of glucagon and catecholamines.
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PMID:Sepsis-induced changes in in vivo insulin action in diabetic rats. 267 27

We have investigated the responsiveness of protein kinetics to insulin and the role of glucose oxidation rate as a mediator of the protein catabolic response to burn injury and sepsis by assessing the response of leucine and urea kinetics to a 5-h hyperinsulinemic euglycemic clamp with and without the simultaneous administration of dichloroacetate (DCA) (to further increase glucose oxidation via stimulation of pyruvate dehydrogenase activity) in eight severely burned and eight septic patients. Leucine and urea kinetics were measured by the primed-constant infusions of [1(-13)C]leucine and [15N2]urea. Compared with controls, basal leucine kinetics (flux and oxidation) were significantly elevated (P less than 0.01) in both groups of patients. Hyperinsulinemia elicited significant (P less than 0.05) decreases in leucine kinetics in both groups of patients. Consistent with this observation, hyperinsulinemia caused urea production to decrease significantly (P less than 0.05) in both patient groups. The administration of DCA to patients during hyperinsulinemia elicited a significant increase in glucose oxidation rate compared with the clamp rate (P less than 0.05), and the percent of glucose uptake oxidized increased from 45.5 +/- 5.5 to 53.5 +/- 4.8%; yet the response of leucine and urea kinetics to the clamp plus DCA was not different from the response to the clamp alone. These results suggest that the maximal effectiveness of insulin to suppress protein breakdown is not impaired and that a deficit in glucose oxidation or energy supply is probably not playing a major role in mediating the protein catabolic response to severe burn injury and sepsis.
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PMID:Role of insulin and glucose oxidation in mediating the protein catabolism of burns and sepsis. 267 28

The effect of sterile inflammation and sepsis on the release of lactate and amino acids by peripheral tissues was investigated in rats by removing the splanchnic organs (liver + small intestines) from the circulation and monitoring changes in blood metabolites over 30 min. Functional hepatectomy was performed in rats 5-7 days following the intraperitoneal introduction of a fecal-agar pellet (sterile vs. Bacteroides fragilis + E. coli). Lactate was significantly (P less than .05) increased in each of the conditions following hepatectomy but was raised to a significantly greater extent in sepsis (P less than .05). A similar response was observed for glutamine while alanine was only significantly (P less than .05) increased in sepsis following hepatectomy. Branched chain amino acids (BCAA) showed differential changes in sepsis compared to control. In control and sterile inflammation, functional hepatectomy was associated with significant decreases (P less than .05) in BCAA. In sepsis, BCAA were not decreased following hepatectomy and were significantly (P less than .05) elevated relative to control or sterile inflammation. Phenylalanine concentrations were not altered in control or sterile inflammation but were significantly elevated in sepsis (P less than .05). Insulin attenuated the accumulation of lactate and amino acids in fed control animals, following functional hepatectomy. However, in septic animals, insulin failed to prevent the rise in plasma lactate following hepatectomy.
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PMID:Role of extra-splanchnic organs in the metabolic response to sepsis: effect of insulin. 267 32


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