Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0036690 (sepsis)
 59,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Low arterial blood pH and sustained nitric oxide (NO) production are critical parameters in inflammatory events such as sepsis, and appropriate treatment is still under debate. Because the stability of nitrogen and oxygen intermediates is dependent on the surrounding pH, we investigated whether the relationship among NO, peroxynitrite (ONOO-), and reactive oxygen species production also depends on the pH value, particularly with respect to their effects on hepatocellular damage. Our studies demonstrate that the extracellular pH influences NO and hydroxyl radical (OH) production in hepatocytes. Acidification (pH 7.0) of the medium revealed a significant increase (P < 0.05) of OH-like radicals, enhanced hepatocellular damage, and a sharp drop in cellular glutathione (GSH) content compared with levels measured at physiological or alkaline pH conditions. Furthermore, inhibition of NO synthesis at all pH conditions resulted in decreased NO production and cellular GSH levels but a simultaneous increase of OH-like radicals and hepatocellular damage with a maximum seen at pH 7.0. Our results suggest that hepatocellular damage is in part regulated by the surrounding pH and that inhibition of NO synthesis at acidic conditions (e.g., in sepsis) leads to increased reactive oxygen-mediated cell injury.
 ...
PMID:pH-dependent changes of nitric oxide, peroxynitrite, and reactive oxygen species in hepatocellular damage. 937 10

In vivo cysteine metabolism during the inflammatory state has been studied minimally. We investigated cysteine metabolism (i.e. taurine, sulfate and glutathione formation) using a single dose of [35S] cysteine in septic rats that had been injected with live Escherichia coli into the tail vein and in control, pair-fed rats. Cysteine metabolites were separated by ion exchange chromatography, and radioactivity was counted in the different fractions. Radioactivity incorporated in tissue proteins was also measured after protein precipitation. [35S]Sulfate production was significantly lower in septic rats than in pair-fed rats. [35S]Taurine contents were significantly lower only in kidneys, spleen and gastrointestinal tract of septic rats. The higher production of [35S] taurine in the livers (the major site of taurine production) of septic rats could have a protective effect against oxidation. Glutathione concentrations were also significantly greater in liver, spleen, kidneys and gastrocnemius muscle of septic rats, presumably in order to combat oxidative stress induced by sepsis. [35S]Cysteine incorporation in glutathione was significantly higher in spleen and kidneys but not in liver of septic rats compared to pair-fed rats. This could be explained by the fact that, in liver, a greater amount of labeled glutathione had been utilized for host defense, or by a high level in glutathione turnover. Finally, [35S]cysteine incorporation into protein, in septic rats, was significantly greater than in pair-fed rats in spleen, lung and particulary in whole plasma proteins other than albumin, which mainly represent the acute-phase proteins. These data suggest an increased requirement for cysteine during sepsis in rats.
 ...
PMID:Metabolism of cysteine is modified during the acute phase of sepsis in rats. 943 Jun 9

Reactive oxygen species, formed in various biochemical reactions, are normally scavenged by antioxidants. Glutathione in its reduced form (GSH) is the most powerful intracellular antioxidant, and the ratio of reduced to oxidised glutathione (GSH:GSSG) serves as a representative marker of the antioxidative capacity of the cell. Several clinical conditions are associated with reduced GSH levels which as a consequence can result in a lowered cellular redox potential. GSH and the redox potential of the cell are components of the cell signaling system influencing the translocation of the transcription factor NF kappa B which regulates the synthesis of cytokines and adhesion molecules. Therefore, one possibility to protect cells from damage caused by reactive oxygen species is to restore the intracellular glutathione levels. Cellular GSH concentration can be influenced by exogenous administration of GSH (as intravenous infusion or as aerosol), of glutathione esters or of GSH precursors such as glutamine or cysteine (in form of N-acetyl-L-cysteine, alpha-lipoic acid). The modulation of GSH metabolism might present a useful adjuvant therapy in many pathologies such as intoxication, diabetes, uremia, sepsis, inflammatory lung processes, coronary disease, cancer and immunodeficiency states.
 ...
PMID:Therapeutic potential of glutathione. 1100 22

Heme oxygenase (HO)-1, the rate-limiting enzyme in heme degradation, is induced by oxidative stress and its major end product, bilirubin, is a potent physiological antioxidant. We studied the induction of HO-1 and bilirubin production in intestinal mucosa using a rat model of sepsis. E. coli lipopolysaccharide was administered intraperitonealy to male Wistar rats and intestinal mucosa was harvested. Intestinal lipid peroxides increased significantly at 1 hr and peaked at 170% of the control value at 5 hr. GSH significantly decreased at 3 hr, reaching the nadir of 50% of the control value at 5 hr. HO-1 mRNA was maximally induced fivefold at 3 hr and HO-1 protein maximally increased to 10 times the control value at 7.5 hr. Both bilirubin and bilirubin oxidative metabolites were maximally increased at 10 hr, to 4.3 and 3.7 times the control value, respectively. These data suggest that oxidative stress in sepsis quickly induces HO-1 in intestinal mucosa and that subsequent production of bilirubin works as an antioxidant. The small intestinal mucosa is an active participant in the general response to sepsis.
 ...
PMID:Administration of bacterial lipopolysaccharide to rats induces heme oxygenase-1 and formation of antioxidant bilirubin in the intestinal mucosa. 1125 50

In septic patients, chronic alcohol abuse increases the incidence of the acute respiratory distress syndrome (ARDS). Because alveolar type II cell viability is critical for epithelial repair, our objective was to determine if chronic ethanol ingestion increased the sensitivity of type II cells to the inflammatory mediators upregulated during sepsis. In rats chronically fed ethanol, type II cell mitochondrial GSH was depleted, and tumor necrosis factor-alpha (TNF-alpha)-induced generation of mitochondrial reactive oxygen species (ROS) and apoptosis were potentiated. When added to the ethanol diet, the GSH precursor (-)-2-oxo-4-thiazolidinecarboxylic acid (Procysteine; Pro) but not N-acetylcysteine (NAC) normalized type II cell mitochondrial GSH. Likewise, Pro but not NAC normalized TNF-alpha-induced mitochondrial ROS and apoptosis. This suggested that chronic ethanol ingestion potentiated TNF-alpha-induced apoptosis in type II cells via mitochondrial GSH depletion. This may be particularly relevant in ARDS when type II cell viability is critical to repair of the damaged alveolar epithelium and may have important ramifications for the treatment of ARDS patients with a history of alcohol abuse.
 ...
PMID:Chronic ethanol ingestion potentiates TNF-alpha-mediated oxidative stress and apoptosis in rat type II cells. 1143 12

Neutrophils have a dual role in sepsis-defending against infection and mediating organ failure. Because glutathione (GSH) is lower in sepsis, the hypothesis that GSH depletion might impair the migratory response of neutrophils to infection was tested. In a mouse model of polymicrobial sepsis induced by cecal ligation and puncture, GSH depletion inhibited peritoneal neutrophil infiltration, increased bacterial colonies, augmented pulmonary neutrophil infiltrate, and worsened survival. The reduced peritoneal influx of neutrophils was explained by a reduced in vivo neutrophil migration in response to locally administered chemokines and by reduced chemotactic activity and chemokine levels in peritoneal lavage fluid. Conversely, the GSH precursor N-acetyl-l-cysteine augmented neutrophil infiltration in the peritoneum but not in the lung, decreased bacterial colonies, and improved survival. Thus, migration of neutrophils to a site of infection and to a distant site is differently regulated, and optimal GSH levels are important for an efficient response to sepsis.
 ...
PMID:Glutathione protects mice from lethal sepsis by limiting inflammation and potentiating host defense. 1193 Mar 21

The diet of industrialised countries is usually rich in amino acids, which are in part used as a source of calories. However, metabolic alterations are observed in diseased patients and a preferential retention of Sulphurated Amino Acids (SAA) occurs during the inflammatory response. Moreover, it has been demonstrated in a model of an acute sepsis phase of rats that the metabolism of Cysteine is modified. The liver converts Cysteine at a different ratio of Sulphate to Taurine (Tau) i.e. the sulphate production decreases while the Tau conversion increases. The Glutathione (GSH) concentration is greater in the liver, kidneys and other organs and the Cysteine incorporation into proteins is higher in the spleen, lungs and plasma (Acute Phase Proteins) while the Albumin level decreases. The pro-inflammatory cytokines such as Interleukin-1, Interleukin-6 and TNF- alpha are the main initiators that alter protein and amino acid metabolism. Another important phenomenon is the impairment of Methionine conversion to Cysteine during stress. For example, premature infants or AIDS patients are capable of synthesizing Cysteine from Methionine at a much lower rate. Thus, the metabolic flow through the trans-sulphuration path may be inadequate to meet the Cysteine demand under critical conditions. In this complex picture, an SAA supply may contribute to an immune system regulation.
 ...
PMID:The regulation of sulphurated amino acid junctions: fact or fiction in the field of inflammation? 1243 3

We investigated the combined effect of glutamine (GLN) and growth hormone (GH) on bacterial translocation (BT) in sepsis. After single intraperitoneal injection of lipopolysaccharide (10 mg/kg), 48 rats were divided randomly into four groups of 12 animals each: the control group received chow orally; the GLN group received chow plus 10% GLN; GH group received chow plus GH; and the GLN/GH group received chow, 10% GLN, and GH. Twenty-four and 96 hr later, rats were sacrificed. Portal blood culture, bacterial colony counts of cultured mesenteric lymph nodes, mucosal thickness, malondialdehyde (MDA), and glutathione (GSH) levels in the gut mucosa were measured. There was no significant change of the rate of portal blood culture between all treatment groups at 24 and 96 hr. At 24 hr, the rats receiving combined treatment of GLN and GH showed lower bacterial colony counts and mucosal MDA levels than the control rats, and higher mucosal GSH levels than the control and GLN-treated rats. At 96 hr, rats treated with both GLN and GH exhibited lower bacterial colony counts and mucosal MDA levels, and higher mucosal thickness and GSH levels than control, GLN, or GH-treated rats. This study suggests that the combination of GLN and GH may synergistically reduce BT over time in sepsis.
 ...
PMID:Combined administration of glutamine and growth hormone synergistically reduces bacterial translocation in sepsis. 1258 81

Glutathione is quantitatively the most important endogenous scavenger system. Glutathione depletion in skeletal muscle is pronounced following major trauma and sepsis in intensive care unit patients. Also, following elective surgery, glutathione depletion occurs in parallel with a progressive decline in muscle glutamine concentration. The present study was designed to test the hypothesis that glutamine supplementation may counteract glutathione depletion in a human trauma model. A homogeneous group of patients (n = 17) undergoing a standardized surgical procedure were prospectively randomly allocated to receive glutamine (0.56 g x day(-1) x kg(-1)) or placebo as part of isonitrogenous and isocaloric nutrition. Percutaneous muscle biopsies and blood samples were taken pre-operatively and at 24 and 72 h after surgery. The concentrations of muscle glutathione and related amino acids were determined in muscle tissue and plasma. In the control (unsupplemented) subjects, total muscle glutathione had decreased by 47+/-8% and 37+/-11% and reduced glutathione had decreased by 53+/-10% and 45+/-16% respectively at 24 and 72 h after surgery (P < 0.05). In contrast, in the glutamine-supplemented group, no significant post-operative decreases in total or reduced glutathione were seen following surgery. Muscle free glutamine had decreased at 72 h after surgery in both groups, by 41.4+/-14.8% (P < 0.05) in the glutamine-supplemented group and by 46.0+/-14.3% (P < 0.05) in the control group. In conclusion, the present study demonstrates that intravenous glutamine supplementation attenuates glutathione depletion in skeletal muscle in humans following standardized surgical trauma.
 ...
PMID:Glutamine attenuates post-traumatic glutathione depletion in human muscle. 1260 86

Obstructive jaundice is associated with high morbidity and mortality. Major complications such as pulmonary dysfunction, renal failure and sepsis are frequently encountered. Recent studies and observations suggest that the free oxygen radicals (FORs) produced in obstructive jaundice may play a significant role in the etiopathogenesis of acute renal failure (ARF). Thirty rats were divided into three groups, as sham, control and treatment groups containing 10 rats each. Laparatomy was performed on each animal in the control and treatment groups and common bile ducts were ligated. Common bile duct was observed but was not ligated for the rats in the sham group. Saline solution injection was begun on the first day of surgical procedure and repeated once a day during the following 5 days. The same procedure was performed with oxygen radical scavenger dimethyl sulfoxide (1.5 mg/kg/day i.p.) instead of saline in the treatment group. The rats were sacrificed on the 7th postoperative day. On the 7th postoperative day, the bilirubin, urea and creatinine levels of the control and treatment groups were significantly higher in comparison with the sham group (p < 0.01). Although there was no statistically significant difference between the bilirubin levels of the control and treatment groups (p > 0.05), the urea and creatinine levels in the treatment group were significantly lower (p < 0.01). On the 7th postoperative day, the erythrocyte superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels of the control and treatment groups were significantly lower than those of the sham group (p < 0.01), whereas renal and erythrocyte malondialdehyde (MDA) levels were significantly higher (p < 0.01). Although SOD and GSH-Px levels did not differ significantly between the treatment and control groups (p > 0.05), renal and erythrocyte MDA levels of the treatment group were significantly lower than those of the control group (p < 0.01). The histopathological scores were significantly higher in the control and treatment groups (p < 0.01); there was no significant difference between the control and treatment groups (p > 0.05). FORs seem to play a significant role in the etiopathogenesis of renal failure in obstructive jaundice. Antioxidant treatment may decrease oxidative damage due to FORs and may prevent renal failure.
 ...
PMID:Role of oxygen free radical scavengers in acute renal failure complicating obstructive jaundice. 1274 May 34


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>