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)

Apoptosis is a key pathogenic mechanism in sepsis that induces extensive death of lymphocytes and dendritic cells, thereby contributing to the immunosuppression that characterizes the septic disorder. Numerous animal studies indicate that prevention of apoptosis in sepsis improves survival and may represent a potential therapy for this highly lethal disorder. Recently, novel cell-penetrating peptide constructs such as HIV-1 TAT basic domain and related peptides have been developed to deliver bioactive cargoes and peptides into cells. In the present study, we investigated the effects of sepsis-induced apoptosis in Bcl-x(L) transgenic mice and in wild-type mice treated with an antiapoptotic TAT-Bcl-x(L) fusion protein and TAT-BH4 peptide. Lymphocytes from Bcl-x(L) transgenic mice were resistant to sepsis-induced apoptosis, and these mice had a approximately 3-fold improvement in survival. TAT-Bcl-x(L) and TAT-BH4 prevented Escherichia coli-induced human lymphocyte apoptosis ex vivo and markedly decreased lymphocyte apoptosis in an in vivo mouse model of sepsis. In conclusion, TAT-conjugated antiapoptotic Bcl-2-like peptides may offer a novel therapy to prevent apoptosis in sepsis and improve survival.
 ...
PMID:TAT-BH4 and TAT-Bcl-xL peptides protect against sepsis-induced lymphocyte apoptosis in vivo. 1662 15

Myocardial dysfunction is a major consequence of septic shock and contributes to the high mortality of sepsis. We have previously reported that glucan phosphate (GP) significantly increased survival in a murine model of cecal ligation and puncture (CLP)-induced sepsis. In the present study, we examined the effect of GP on cardiac dysfunction in CLP-induced septic mice. GP was administered to ICR/HSD mice 1 h before induction of CLP. Sham surgically operated mice served as control. Cardiac function was significantly decreased 6 h after CLP-induced sepsis compared with sham control. In contrast, GP administration prevented CLP-induced cardiac dysfunction. Macrophage migration inhibitory factor (MIF) has been implicated as a major factor in cardiomyocyte apoptosis and cardiac dysfunction during septic shock. CLP increased myocardial MIF expression by 88.3% (P < 0.05) and cardiomyocyte apoptosis by 7.8-fold (P < 0.05) compared with sham control. GP administration, however, prevented CLP-increased MIF expression and decreased cardiomyocyte apoptosis by 51.2% (P < 0.05) compared with untreated CLP mice. GP also prevented sepsis-caused decreases in phospho-Akt, phospho-GSK-3beta, and Bcl-2 levels in the myocardium of septic mice. These data suggest that GP treatment attenuates cardiovascular dysfunction in fulminating sepsis. GP administration also activates the phosphoinositide 3-kinase/Akt pathway, decreases myocardial MIF expression, and reduces cardiomyocyte apoptosis.
 ...
PMID:Glucan phosphate attenuates cardiac dysfunction and inhibits cardiac MIF expression and apoptosis in septic mice. 1676 37

The objective of the present study was to investigate the effects of recombinant human growth hormone (rhGH) on the intestinal mucosa barrier of septic rats and explore its possible mechanism. Female Sprague-Dawley rats were randomized into three groups: control, Escherichia coli-induced sepsis (S) and treatment (T) groups. Groups S and T were subdivided into subgroups 1d and 3d, respectively. Expression of liver insulin-like growth factor-1 (IGF-1) mRNA, Bcl-2 and Bax protein levels and the intestinal Bax/Bcl-2 ratio, and plasma GH and IGF-1 levels were determined. Histological examination of the intestine was performed and bacterial translocation was determined. rhGH significantly attenuated intestinal mucosal injuries and bacterial translocation in septic rats, markedly decreased Bax protein levels, inhibited the decrease of Bcl-2 protein expression and maintained the Bax/Bcl-2 ratio in the intestine. rhGH given after sepsis significantly improved levels of plasma GH (T1d: 1.28 +/- 0.24; T3d: 2.14 +/- 0.48 microg/L vs S1d: 0.74 +/- 0.12; S3d: 0.60 +/- 0.18 microg/L; P < 0.05) and IGF-1 (T1d: 168.94 +/- 65.67; T3d: 201.56 +/- 64.98 microg/L vs S1d: 116.72 +/- 13.96; S3d: 107.50 +/- 23.53 microg/L; P < 0.05) and expression of liver IGF-1 mRNA (T1d: 0.98 +/- 0.20; T3d: 1.76 +/- 0.17 vs S1d: 0.38 +/- 0.09; S3d: 0.46 +/- 0.10; P < 0.05). These findings indicate that treatment with rhGH had beneficial effects on the maintenance of the integrity of the intestinal mucosa barrier in septic rats.
 ...
PMID:Beneficial effect of recombinant human growth hormone on the intestinal mucosa barrier of septic rats. 1722 95

The current comparative investigation analyses markers of inflammation and apoptosis in peripheral blood of intensive care unit (ICU) patients with postoperative/posttraumatic SIRS (systemic inflammatory response syndrome), sepsis, severe sepsis, or septic shock. Inflammatory markers (C-reactive protein [CRP], cytokines, metalloproteinases [MMPs]) and soluble FAS-Ligand (sCD178) were determined in plasma, and apoptosis-relevant antigens such as active caspase-3, Bcl-2, and sCD178 were quantified in whole-blood cell lysates. These parameters were analyzed daily in 20 postoperative/posttraumatic patients: 2 patients had SIRS, 5 suffered from sepsis (2 died), and 13 had septic shock (5 died). Active caspase-3, Bcl-2, and sCD178 were determined by ELISA and by fluorescence-activated cell sorting (FACS)-array kits using bead-assisted flow cytometry. Cytokines and MMPs were quantified by Luminex-assisted Beadlyte assays. Active caspase-3 was identified in defined samples of whole-blood lysates covering, for example, 5/7, 8/18, and 6/11 consecutive days during the patients' stay on the ICU. Also, sCD178 was detected on successive days. Peaks of active caspase-3 antigen contents in whole blood occurred independently of CRP and inflammatory cytokines such as tumor necrosis factor (TNF)-alpha and IL-6. In addition, high MMPs 1-3, 7-10, and 13 concentrations were detected. Interestingly, active caspase-3 and cell-associated sCD178 were either elevated simultaneously or in a close time window. The same was true for Bcl-2. In conclusion, activation of apoptosis can be determined in whole blood of postoperative/posttraumatic patients by active caspase-3 and by Bcl-2. Pro- and antiapoptotic effects during sepsis may occur independently of peaks in inflammatory markers. Apoptosis could explain modeling and remodeling of leukocyte subpopulations.
 ...
PMID:Caspase-3 activation, Bcl-2 contents, and soluble FAS-ligand are not related to the inflammatory marker profile in patients with sepsis and septic shock. 1738 59

Recent research has yielded many interesting and potentially important therapeutic targets in sepsis. Specifically, the effects of antagonistic anti-cytokine therapies (tumor necrosis factor-alpha [TNF-alpha], interleukin-1 [IL-1]) and anti-endotoxin strategies utilizing antibodies against endotoxin or endotoxin receptor/carrier molecules (anti-CD14 or anti-LPS-binding protein) have been studied. Unfortunately, these approaches often failed clinically, and in many cases, the efficacy of these treatments was dependent on the severity of sepsis. Recently, clinical trials using insulin to lock blood glucose levels and activated protein C treatment have showed that while they provided some survival benefit, their efficacy does not appear to be predicated solely upon anti-inflammatory effects. Here, we will review work done in animal models of polymicrobial sepsis and clinical findings that support the hypothesis that apoptosis in the immune system is a pathologic event in sepsis that can be a therapeutic target. In this respect, experimental studies looking at the septic animal suggest that loss of lymphocytes during sepsis may be due to dysregulated apoptosis and that this appears to be brought on by a variety of mediators effecting 'intrinsic' as well as 'extrinsic' cell death pathways. From a therapeutic perspective this has provided a number of novel targets for clinically successful current, as well as future therapies, such as caspases (caspase inhibition/protease inhibition), pro-apoptotic protein-expression (via administration and/or over-expression of Bcl-2) and the death receptor family Fas-FasL (via. FasFP [fas fusion protein] and the application of siRNA against a number pro-apoptotic factors).
 ...
PMID:The apoptotic pathway as a therapeutic target in sepsis. 1743 Jan 19

LPS has been implicated in the pathogenesis of endothelial cell death associated with Gram-negative bacterial sepsis. The binding of LPS to the TLR-4 on the surface of endothelial cells initiates the formation of a death-inducing signaling complex at the cell surface. The subsequent signaling pathways that result in apoptotic cell death remain unclear and may differ among endothelial cells in different organs. We sought to determine whether LPS and cycloheximide-induced cell death in human lung microvascular endothelial cells (HmVECs) was dependent upon activation of the intrinsic apoptotic pathway and the generation of reactive oxygen species. We found that cells overexpressing the anti-apoptotic protein Bcl-X(L) were resistant to LPS and cycloheximide-induced death and that the proapoptotic Bcl-2 protein Bid was cleaved following treatment with LPS. The importance of Bid was confirmed by protection of Bid-deficient (bid(-/-)) mice from LPS-induced lung injury. Neither HmVECs treated with the combined superoxide dismutase/catalase mimetic EUK-134 nor HmVECs depleted of mitochondrial DNA (rho(0) cells) were protected against LPS and cycloheximide-induced death. We conclude that LPS and cycloheximide-induced death in HmVECs requires the intrinsic cell death pathway, but not the generation of reactive oxygen species.
 ...
PMID:The intrinsic apoptotic pathway is required for lipopolysaccharide-induced lung endothelial cell death. 1764 Oct 50

The recombinant human activated protein C (rhAPC) has been reported to reduce mortality in patients with severe sepsis. An anti-apoptotic effect of rhAPC in sepsis is known, but the mechanism through which it acts on the apoptotic pathway is still unclear. Therefore, immunopositivity of the apoptosis-related proteins Bcl-2, an anti-apoptotic protein, c-myc, a proliferative protein, p-21 and p-53, two apoptotic proteins, was determined after rhAPC treatment in a mouse sepsis model. Sepsis was induced by Escherichia coli endotoxin injection. Increased neutrophil infiltration and immunoreactivity to p53 and p21 were observed in the group with sepsis and these immunoreactivities were decreased by rhAPC treatment. In the sepstic group; immunopositivity of Bcl-2 and c-myc was mild and moderate, respectively. In conclusion; p21- and p53-mediated apoptosis was increased in the sepsis model, and for the first time it has been shown that rhAPC decreases sepsis-induced apoptosis resulting from increased p21 and p53 proteins.
 ...
PMID:Effect of recombinant human activated protein C on apoptosis-related proteins. 1766 60

To assess the degree of lymphocyte apoptosis and survival in mice treated with small interfering RNA (siRNA) targeted to Bim, a proapoptotic molecule from the Bcl-2 family, within a clinically relevant model of sepsis. C57BL/6 mice were treated with a single dose of Bim siRNA complexed in cationic liposomes via tail vein injection. Approximately 24 h later, mice were subjected to either cecal ligation and puncture (CLP) or sham surgery. Animals were killed at 20 h postsurgery, and spleens were harvested for fluorescence-activated cell sorting analysis using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling as a marker for apoptosis. A second cohort of mice was followed for survival for 7 days. The degree of lymphocyte apoptosis in Bim siRNA-treated mice was markedly decreased compared with controls. Fluorescent activated cell sorter analysis demonstrated 13.1% +/- 1.2% B-cell apoptosis and 11.5% +/- 1.5% T-cell apoptosis in control mice compared with 2.7% +/- 0.4% B-cell apoptosis and 3.9% +/- 0.3% T-cell apoptosis in Bim siRNA-treated mice after CLP (P < 0.001 and P < 0.01, respectively). This striking difference in lymphocyte apoptosis correlated with a significant survival advantage in Bim siRNA-treated mice. At 7 days, there was 90% overall survival in Bim siRNA-treated septic mice compared with 50% overall survival in control septic mice (P < 0.05). Treatment with Bim siRNA in vivo has the potential to be an effective therapy in the treatment of sepsis.
 ...
PMID:Bim siRNA decreases lymphocyte apoptosis and improves survival in sepsis. 1819 42

Darbepoetin alpha (DA), a long-acting erythropoietin derivative stimulating erythropoiesis, can, by antiapoptotic effects, mitigate myocardial I/R injury. We tested the hypothesis that DA treatment improves left ventricular function (LV) in LPS evoked cardiomyopathy and alters gene expression of apoptosis-regulating proteins (Bcl-XL, Bcl-2, Bax, and Bcl-Xs) and TNF-alpha. In a prospective, controlled, randomized study in Lewis rats (n = 56; 8 groups), myocardial depression was evoked by LPS administration (serotype O127:B8; 10 mg/kg, i.p.). Darbepoetin alpha or vehicle was injected either 24 h before (pretreatment) or 2 h after LPS injection (treatment). Hearts were isolated 8 h after LPS injection, perfused (Krebs-Henseleit solution) in a Langendorff apparatus, and LV developed pressure and its derivatives were measured. For gene expression analysis, real-time polymerase chain reaction of LV specimen was performed. LPS decreased LV developed pressure (-64.6 +/- 7.9 mmHg) and its derivates by more than 60% in comparison to vehicle (P < 0,01), but this effect was not attenuated by DA pretreatment or DA treatment. LPS administration increased gene expression of Bcl-Xs, Bax, and TNF-alpha, but this was not altered by DA pretreatment. Furthermore, there was no effect on Bcl-Xl and Bcl-2 expression by DA alone. Whereas proapoptotic genes of the myocardium are up-regulated in LPS-induced cardiomyopathy, neither DA pretreatment nor treatment has significant effects on LV function or gene expression. This may suggest cardiac resistance to darbepoetin in LPS-mediated sepsis.
 ...
PMID:Darbepoetin alpha, a long-acting erythropoeitin derivate, does not alter LPS evoked myocardial depression and gene expression of Bax, Bcl-Xs, Bcl-XL, Bcl-2, and TNF-alpha. 1849 5

This study examined the fate of dendritic cells (DCs) and macrophages (M Phi) in vivo in a murine model of sepsis. Wild-type, knockout, and transgenic mice were used to examine the role of Bcl-2 family members on the regulation of splenic DCs and M Phi survival. Bim knockout (Bim) mice and mice overexpressing Bcl-2 in selected hematopoietic cells were used: (a) overexpression of Bcl-2 in all hematopoietic cells using a vav promoter (Vav-Bcl-2) and (b) overexpression of Bcl-2 in all Major histocompatibility complex (MHC) class I cells (H-2K-Bcl-2). Mice underwent sham surgery or cecal ligation and puncture, and absolute numbers of splenic DCs and M Phi were determined. Importantly, two distinct M Phi populations, that is, well-differentiated "mature" M Phi population and a less differentiated "immature," "monocyte-like" (IM Phi) population were identified that demonstrated differential susceptibility to apoptosis. In wild-type mice, sepsis induced a 64% +/- 7% and a 77% +/- 3% decrease in absolute cell numbers of splenic DCs and IM Phi, respectively (n = 7, P < 0.05). Mature M Phi were not depleted in sepsis. No significant cell depletion was evident in Vav-Bcl-2, H-2K-Bcl-2, or Bim mice. We conclude that sepsis induces a major depletion of developing M Phi as well as DCs, and this depletion may be an important mechanism of immune suppression in sepsis.
 ...
PMID:Modulation of the Bcl-2 family blocks sepsis-induced depletion of dendritic cells and macrophages. 1883 43


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