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

Melatonin, or N-acetyl-5-methoxytryptamine, is a compound derived from tryptophan that is found in all organisms from unicells to vertebrates. This indoleamine may act as a protective agent in disease conditions such as Parkinson's, Alzheimer's, aging, sepsis and other disorders including ischemia/reperfusion. In addition, melatonin has been proposed as a drug for the treatment of cancer. These disorders have in common a dysfunction of the apoptotic program. Thus, while defects which reduce apoptotic processes can exaggerate cancer, neurodegenerative disorders and ischemic conditions are made worse by enhanced apoptosis. The mechanism by which melatonin controls cell death is not entirely known. Recently, mitochondria, which are implicated in the intrinsic pathway of apoptosis, have been identified as a target for melatonin actions. It is known that melatonin scavenges oxygen and nitrogen-based reactants generated in mitochondria. This limits the loss of the intramitochondrial glutathione and lowers mitochondrial protein damage, improving electron transport chain (ETC) activity and reducing mtDNA damage. Melatonin also increases the activity of the complex I and complex IV of the ETC, thereby improving mitochondrial respiration and increasing ATP synthesis under normal and stressful conditions. These effects reflect the ability of melatonin to reduce the harmful reduction in the mitochondrial membrane potential that may trigger mitochondrial transition pore (MTP) opening and the apoptotic cascade. In addition, a reported direct action of melatonin in the control of currents through the MTP opens a new perspective in the understanding of the regulation of apoptotic cell death by the indoleamine.
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PMID:Melatonin mitigates mitochondrial malfunction. 1561 31

S-nitrosation of mitochondrial proteins has been proposed to contribute to the pathophysiological interactions of nitric oxide (NO) and its derivatives with mitochondria but has not been shown directly. Furthermore, little is known about the mechanism of formation or the fate of these putative S-nitrosothiols. Here we have determined whether mitochondrial membrane protein thiols can be S-nitrosated on exposure to free NO from 3,3-bis(aminoethyl)-1-hydroxy-2-oxo-1-triazene (DETA-NONOate) by interaction with S-nitrosoglutathione or S-nitroso-N-acetylpenicillamine (SNAP) and by the NO derivative peroxynitrite. S-Nitrosation of protein thiols was measured directly by chemiluminescence detection. S-Nitrosoglutathione and S-nitroso-N-acetylpenicillamine led to extensive protein thiol oxidation, with about 30% of the modified protein thiols persistently S-nitrosated. In contrast, there was no protein thiol oxidation or S-nitrosation on exposure to 3,3-bis (aminoethyl)-1-hydroxy-2-oxo-1-triazene. Peroxynitrite extensively oxidized protein thiols but produced negligible amounts of S-nitrosothiols. Therefore, mitochondrial membrane protein thiols are S-nitrosated by preformed S-nitrosothiols but not by NO or by peroxynitrite. These S-nitrosated protein thiols were readily reduced by glutathione, so S-nitrosation will only persist when the mitochondrial glutathione pool is oxidized. Respiratory chain complex I was S-nitrosated by S-nitrosothiols, consistent with it being an important target for S-nitrosation during nitrosative stress. The S-nitrosation of complex I correlated with a significant loss of activity that was reversed by thiol reductants. S-Nitrosation was also associated with increased superoxide production from complex I. These findings point to a significant role for complex I S-nitrosation and consequent dysfunction during nitrosative stress in disorders such as Parkinson disease and sepsis.
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PMID:Persistent S-nitrosation of complex I and other mitochondrial membrane proteins by S-nitrosothiols but not nitric oxide or peroxynitrite: implications for the interaction of nitric oxide with mitochondria. 1648 25

Critically ill patients treated for multiple organ failure often develop muscle dysfunction. Here we test the hypothesis that mitochondrial and energy metabolism are deranged in leg and intercostal muscle of critically ill patients with sepsis-induced multiple organ failure. Ten critically ill patients suffering from sepsis-induced multiple organ failure and requiring mechanical ventilation were included in the study. A group (n = 10) of metabolically healthy age- and sex-matched patients undergoing elective surgery were used as controls. Muscle biopsies were obtained from the vastus lateralis (leg) and intercostal muscle. The activities of citrate synthase and mitochondrial respiratory chain complexes I and IV and concentrations of ATP, creatine phosphate, and lactate were analyzed. Morphological evaluation of mitochondria was performed by electron microscopy. Activities of citrate synthase and complex I were 53 and 60% lower, respectively, in intercostal muscle of the patients but not in leg muscle compared with controls. The activity of complex IV was 30% lower in leg muscle but not in intercostal muscle. Concentrations of ATP and creatine phosphate were, respectively, 40 and 34% lower, and lactate concentrations were 43% higher in leg muscle but not in intercostal muscle. We conclude that both leg and intercostal muscle show a twofold decrease in mitochondrial content in intensive care unit patients with multiple organ failure, which is associated with lower concentrations of energy-rich phosphates and an increased anaerobic energy production in leg muscle but not in intercostal muscle.
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PMID:Derangements in mitochondrial metabolism in intercostal and leg muscle of critically ill patients with sepsis-induced multiple organ failure. 1680 54

Ten years after starting my pediatric career at the Japanese Red Cross Central Hospital (now Japanese Red Cross Medical Center) in Tokyo, I examined on January 5, 1961, a 4 year-3 month old boy, with curious clinical symptom-complex I had never experienced. This patient was a typical Kawasaki disease patient. But at that time I was unable to make a diagnosis. In February 1962, a case of suspected sepsis was referred to me from a neighboring doctor. After admitting the child into the hospital, the patient had a similar clinical course as the previous patient. I realized that there were 2 patients with similar unique clinical symptom complexes that did not exist in any medical reference book. From March to September 1962, I was able to see 5 patients who fell into the same category. In 1967, I published my original article entitled, "Infantile Acute febrile Muco-cutaneous lymph node syndrome: clinical observations of 50 cases".
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PMID:[Recognition of KD]. 1826 54

The mechanisms responsible to the development of brain dysfunction during sepsis are not well understood. The objective of this study is to evaluate mitochondrial respiratory chain and creatine kinase activities in the brain after cecal ligation and perforation (CLP) in rats. We performed a prospective, controlled experiment in male Wistar rats. Rats were subjected to CLP (sepsis group) with saline resuscitation (at 50mL/kg immediately and 12h after cecal ligation and perforation) or sham operation (control group). Several times (0, 6, 12, 24, 48 and 96h) after CLP six rats were killed by decapitation, and brain structures (cerebellum, hippocampus, striatum and cortex) were isolated. Mitochondrial respiratory chain and creatine kinase activity were then measured. It was observed that animals submitted to CLP presented decreased mitochondrial respiratory chain activity in complex I, but not in complex II, III and IV, 24, 48 and 96h in all analyzed structures. Activity of succinate dehydrogenase was decreased in 48 and 96h in all analyzed structures. Creatine kinase activity increased after CLP in cerebellum, hippocampus and cortex (after 0h) and striatum (after 6h). Sepsis associated brain injury may include dysfunction in the mitochondrial respiratory chain activity.
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PMID:Mitochondrial respiratory chain and creatine kinase activities in rat brain after sepsis induced by cecal ligation and perforation. 1865 32

The aims of this work were to study the mitochondrial function and to evaluate (a) the oxidative stress in real time in an acute model of endotoxemia and (b) the effect of alpha-lipoic acid (LA, 100 mg/kg) as a therapeutic strategy to be considered. In rats treated with lipopolisaccharide (LPS, 10 mg/kg), a 1.4-fold increase was observed in in situ skeletal muscle chemiluminescence. Experimental sepsis increased oxygen consumption in tissue cubes (1 mm(3)) by 30% for heart and diaphragm and impaired state 3 mitochondrial respiration rate in the three organs (liver, diaphragm and heart) studied. Only complex I activity in heart and diaphragm and complex IV activity in diaphragm were found impaired in this septic model. The production of NO by submitochondrial membranes was found increased by 80% in the diaphragm and by 35% in the heart of septic rats. The treatment with LA prevented the oxidative stress and mitochondrial dysfunction observed in this model.
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PMID:The oxidative stress and the mitochondrial dysfunction caused by endotoxemia are prevented by alpha-lipoic acid. 1905 Oct 79

Melatonin prevents mitochondrial failure in models of sepsis through its ability to inhibit the expression and activity of both cytosolic (iNOS) and mitochondrial (i-mtNOS) inducible nitric oxide synthases. Because Parkinson's disease (PD), like sepsis, is associated with iNOS induction, we assessed the existence of changes in iNOS/i-mtNOS and their relation with mitochondrial dysfunction in the MPTP model of PD, which also displays increased iNOS expression. We also evaluated the role of melatonin (aMT) and its brain metabolite, N(1)-acetyl-5-methoxykynuramine (AMK), in preventing i-mtNOS induction and mitochondrial failure in this model of PD. Mitochondria from substantia nigra (SN) and, to a lesser extent, from striatum (ST) showed a significant increase in i-mtNOS activity, nitrite levels, oxidative stress, and complex I inhibition after MPTP treatment. MPTP-induced i-mtNOS was probably related to mitochondrial failure, because its prevention by aMT and AMK reduced oxidative/nitrosative stress and restored complex I activity. These findings represent the first experimental evidence of a potential role for i-mtNOS in the mitochondrial failure of PD and support a novel mechanism in the neuroprotective effects of aMT and AMK.
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PMID:Melatonin and its brain metabolite N(1)-acetyl-5-methoxykynuramine prevent mitochondrial nitric oxide synthase induction in parkinsonian mice. 1943 46

Impaired mitochondrial activity has been linked to increased risk for clinical complications after injury. Furthermore, variant mitochondrial alleles have been identified and are thought to result in decreased mitochondrial activity. These include a nonsynonymous mitochondrial polymorphism (T4216C) in the nicotinamide adenine dinucleotide dehydrogenase 1 gene (ND1), encoding a key member of complex I within the electron transport chain, which is found almost exclusively among Caucasians. We hypothesized that burn patients carrying ND1 4216C are less able to generate the cellular energy necessary for an effective immune response and are at increased risk for infectious complications. The association between 4216C and outcome after burn injury was evaluated in a cohort of 175 Caucasian patients admitted to the Parkland Hospital with burns covering greater than or equal to 15% of their total body surface area or greater than or equal to 5% full-thickness burns under an institutional review board-approved protocol. To remove confounding unrelated to burn injury, individuals were excluded if they presented with significant non-burn-related trauma (Injury Severity Score > or =16), traumatic or anoxic brain injury, spinal cord injury, were HIV/AIDS positive, had active malignancy, or survived less than 48 h postadmission. Within this cohort of patients, carriage of the 4216C allele was significantly associated by unadjusted analysis with increased risk for sepsis-related organ dysfunction or septic shock (P = 0.011). After adjustment for full-thickness burn size, inhalation injury, age, and sex, carriage of the 4216C allele was associated with complicated sepsis (adjusted odds ratio = 3.7; 95% confidence interval, 1.5-9.1; P = 0.005), relative to carriers of the T allele.
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PMID:Association of mitochondrial allele 4216C with increased risk for sepsis-related organ dysfunction and shock after burn injury. 1948 83

Catecholamines are frequently used in sepsis, but their interaction with mitochondrial function is controversial. We incubated isolated native and endotoxin-exposed swine liver mitochondria with either dopamine, dobutamine, noradrenaline or placebo for 1 h. Mitochondrial State 3 and 4 respiration and their ratio (RCR) were determined for respiratory chain complexes I, II and IV. All catecholamines impaired glutamate-dependent RCR (p = 0.046), predominantly in native mitochondria. Endotoxin incubation alone induced a decrease in glutamate-dependent RCR compared to control samples (p = 0.002). We conclude that catecholamines and endotoxin impair the efficiency of mitochondrial complex I respiration in vitro.
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PMID:Effects of endotoxin and catecholamines on hepatic mitochondrial respiration. 1960 62

NO has been implicated in the pathogenesis of septic shock. However, the role of NO synthase 3 (NOS3) during sepsis remains incompletely understood. Here, we examined the impact of NOS3 deficiency on systemic inflammation and myocardial dysfunction during peritonitis-induced polymicrobial sepsis. Severe polymicrobial sepsis was induced by colon ascendens stent peritonitis (CASP) in wild-type (WT) and NOS3-deficient (NOS3KO) mice. NOS3KO mice exhibited shorter survival time than did WT mice after CASP. NOS3 deficiency worsened systemic inflammation assessed by the expression of inflammatory cytokines in the lung, liver, and heart. Colon ascendens stent peritonitis markedly increased the number of leukocyte infiltrating the liver and heart in NOS3KO but not in WT mice. The exaggerated systemic inflammation in septic NOS3KO mice was associated with more marked myocardial dysfunction than in WT mice 22 h after CASP. The detrimental effects of NOS3 deficiency on myocardial function after CASP seem to be caused by impaired Ca handling of cardiomyocytes. The impaired Ca handling of cardiomyocytes isolated from NOS3KO mice subjected to CASP was associated with depressed mitochondrial ATP production, a determinant of the Ca cycling capacity of sarcoplasmic reticulum Ca-ATPase. The NOS3 deficiency-induced impairment of the ability of mitochondria to produce ATP after CASP was at least in part attributable to reduction in mitochondrial respiratory chain complex I activity. These observations suggest that NOS3 protects against systemic inflammation and myocardial dysfunction after peritonitis-induced polymicrobial sepsis in mice.
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PMID:Nos3 protects against systemic inflammation and myocardial dysfunction in murine polymicrobial sepsis. 1999 49


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