Intrahepatic STAT-3 activation and acute phase gene expression predict outcome after CLP sepsis in the rat

1998 ◽  
Vol 275 (6) ◽  
pp. G1423-G1429 ◽  
Author(s):  
Kenneth M. Andrejko ◽  
Jodi Chen ◽  
Clifford S. Deutschman
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Acute Phase ◽  
Interleukin 6 ◽  
Cecal Ligation ◽  
Cecal Ligation And Puncture ◽  
Signal Transducer ◽  
Lethal Sepsis

Interleukin-6 (IL-6) regulates hepatic acute phase responses by activating the transcription factor signal transducer and activator of transcription (STAT)-3. IL-6 also may modulate septic pathophysiology. We hypothesize that 1) STAT-3 activation and transcription of α2-macroglobulin (A2M) correlate with recovery from sepsis and 2) STAT-3 activation and A2M transcription reflect intrahepatic and not serum IL-6. Nonlethal sepsis was induced in rats by single puncture cecal ligation and puncture (CLP) and lethal sepsis via double-puncture CLP. STAT-3 activation and A2M transcription were detected at 3–72 h and intrahepatic IL-6 at 24–72 h following single-puncture CLP. All were detected only at 3–16 h following double-puncture CLP and at lower levels than following single-puncture CLP. Loss of serum and intrahepatic IL-6 activity after double-puncture CLP correlated with mortality. Neither intrahepatic nor serum IL-6 levels correlated with intrahepatic IL-6 activity. STAT-3 activation following single-puncture CLP inversely correlated with altered transcription of gluconeogenic, ketogenic, and ureagenic genes. IL-6 may have both beneficial and detrimental effects in sepsis. Fulminant sepsis may decrease the ability of hepatocytes to respond to IL-6.

scholarly journals Contribution of gene expression to metabolic fluxes in hypermetabolic livers induced through burn injury and cecal ligation and puncture in rats

2007 ◽  
Vol 97 (1) ◽  
pp. 118-137 ◽  
Author(s):  
Scott Banta ◽  
Murali Vemula ◽  
Tadaaki Yokoyama ◽  
Arul Jayaraman ◽  
François Berthiaume ◽  
...  
Keyword(s):  
Gene Expression ◽  
Burn Injury ◽  
Cecal Ligation ◽  
Cecal Ligation And Puncture ◽  
Metabolic Fluxes

scholarly journals Signal Transducer and Activator of Transcription (Stat) 5b-Mediated Inhibition of Insulin-Like Growth Factor Binding Protein-1 Gene Transcription: A Mechanism for Repression of Gene Expression by Growth Hormone

2007 ◽  
Vol 21 (6) ◽  
pp. 1443-1457 ◽  
Author(s):  
Mitsuru Ono ◽  
Dennis J. Chia ◽  
Roxana Merino-Martinez ◽  
Amilcar Flores-Morales ◽  
Terry G. Unterman ◽  
...  
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Gene Transcription ◽  
Binding Protein ◽  
Critical Role ◽  
Somatic Growth ◽  
Transcript Profiling ◽  
Signal Transducer ◽  
Igf Binding ◽  
Igf Binding Protein

Abstract GH plays a central role in controlling somatic growth, tissue regeneration, and intermediary metabolism in most vertebrate species through mechanisms dependent on the regulation of gene expression. Recent studies using transcript profiling have identified large cohorts of genes whose expression is induced by GH. Other results have demonstrated that signal transducer and activator of transcription (Stat) 5b, a latent transcription factor activated by the GH receptor-associated protein kinase, Jak2, is a key agent in the GH-stimulated gene activation that leads to somatic growth. By contrast, little is known about the steps through which GH-initiated signaling pathways reduce gene expression. Here we show that Stat5b plays a critical role in the GH-regulated inhibition of IGF binding protein-1 gene transcription by impairing the actions of the FoxO1 transcription factor on the IGF binding protein-1 promoter. Additional observations using transcript profiling in the liver indicate that Stat5b may be a general mediator of GH-initiated gene repression. Our results provide a model for understanding how GH may simultaneously stimulate and inhibit the expression of different cohorts of genes via the same transcription factor, potentially explaining how GH action leads to integrated biological responses in the whole organism.

scholarly journals Inhibition of iNOS protects against the deleterious effects of sub-lethal sepsis and ethanol in the cardiorenal system

2021 ◽  
Author(s):  
Arthur H. Sousa ◽  
Gabriel T. Do Vale ◽  
Jose A Nascimento ◽  
Wanessa Mayumi Carvalho Awata ◽  
Carla Brigagão Pacheco da Silva ◽  
...  
Keyword(s):  
Biochemical Analysis ◽  
Molecular Mechanisms ◽  
Renal Cortex ◽  
Cecal Ligation ◽  
Selective Inhibitor ◽  
Oxygen Species ◽  
Cecal Ligation And Puncture ◽  
Post Surgery ◽  
Lethal Sepsis ◽  
Pro Inflammatory Cytokines

We tested the hypothesis that ethanol would aggravate the deleterious effects of sub-lethal cecal ligation and puncture (SL-CLP) sepsis in the cardiorenal system and that inhibition of iNOS would prevent such response. Male C57BL/6 mice were treated with ethanol for 12 weeks. One hour before SL-CLP surgery, mice were treated with N6-(1-Iminoethyl)-lysine (L-NIL, 5 mg/kg, i.p), a selective inhibitor of iNOS. A second dose of L-NIL was administered 24 h after SL-CLP surgery. Mice were killed 48 h post-surgery and blood, the renal cortex and left ventricle (LV) were collected for biochemical analysis. L-NIL attenuated the increase in serum creatinine levels induced by ethanol, but not by SL-CLP. Ethanol, but not SL-CLP increased creatine kinase (CK)-MB activity and L-NIL did not prevent this response. In the renal cortex, L-NIL prevented the redox imbalance induced by ethanol and SL-CLP. Inhibition of iNOS also decreased lipoperoxidation induced by ethanol and SL-CLP in the LV. L-NIL prevented the increase of pro-inflammatory cytokines and reactive oxygen species (ROS) induced by ethanol and/or SL-CLP in the cardiorenal system, suggesting that iNOS modulated some of the molecular mechanisms that underlie the deleterious effects of both conditions in the cardiorenal system.

Involvement of a NF-kappa B-like transcription factor in the activation of the interleukin-6 gene by inflammatory lymphokines

1990 ◽  
Vol 10 (2) ◽  
pp. 561-568
Author(s):  
H Shimizu ◽  
K Mitomo ◽  
T Watanabe ◽  
S Okamoto ◽  
K Yamamoto
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcriptional Activation ◽  
Interleukin 6 ◽  
Interleukin 1 ◽  
Tnf Alpha ◽  
Nuclear Factor ◽  
Nf Kappa B ◽  
Necrosis Factor Alpha ◽  
Mediators Of Inflammation

Interleukin-6 (IL-6) is one of the major mediators of inflammation, and its expression is inducible by the other inflammatory lymphokines, interleukin-1 (IL-1) and tumor necrosis factor alpha (TNF-alpha). We demonstrate that a common IL-6 promoter element, termed inflammatory lymphokine-responsive element (ILRE), is important for induction of IL-6 gene expression by IL-1 and TNF-alpha despite possible differences in the mechanisms of action of these lymphokines. Remarkably, the ILRE sequence, located between -73 to -63 relative to the mRNA cap site, is highly homologous to NF-kappa B transcription factor-binding motifs and binds an IL-1-TNF-alpha-inducible nuclear factor; the sequence specificities, binding characteristics, and subcellular localizations of this factor are indistinguishable from those of NF-kappa B. In addition, mutations of the ILRE sequence which impair the binding of this nuclear factor abolished the induction of IL-6 gene expression by IL-1 and TNF-alpha in vivo. These results indicate that a nuclear factor indistinguishable from NF-kappa B is involved in the transcriptional activation of the IL-6 gene by IL-1 and TNF-alpha.

scholarly journals Mutational analysis of acute-phase response factor/Stat3 activation and dimerization.

1997 ◽  
Vol 17 (8) ◽  
pp. 4677-4686 ◽  
Author(s):  
J Sasse ◽  
U Hemmann ◽  
C Schwartz ◽  
U Schniertshauer ◽  
B Heesel ◽  
...  
Keyword(s):  
Tyrosine Phosphorylation ◽  
Acute Phase ◽  
Interleukin 6 ◽  
Acute Phase Response ◽  
Phase Response ◽  
Response Factor ◽  
Transactivation Domain ◽  
Signal Transducer ◽  
Amino Terminal ◽  
Carboxy Terminal

Signal transducer and transcription (STAT) factors are activated by tyrosine phosphorylation in response to a variety of cytokines, growth factors, and hormones. Tyrosine phosphorylation triggers dimerization and nuclear translocation of these transcription factors. In this study, the functional role of carboxy-terminal portions of the STAT family member acute-phase response factor/Stat3 in activation, dimerization, and transactivating potential was analyzed. We demonstrate that truncation of 55 carboxy-terminal amino acids causes constitutive activation of Stat3 in COS-7 cells, as is known for the Stat3 isoform Stat3beta. By the use of deletion and point mutants, it is shown that both carboxy- and amino-terminal portions of Stat3 are involved in this phenomenon. Dimerization of Stat3 was blocked by point mutations affecting residues both in the vicinity of the tyrosine phosphorylation site (Y705) and more distant from this site, suggesting that multiple interactions are involved in dimer formation. Furthermore, by reporter gene assays we demonstrate that carboxy-terminally truncated Stat3 proteins are incapable of transactivating an interleukin-6-responsive promoter in COS-7 cells. In HepG2 hepatoma cells, however, these truncated Stat3 forms transmit signals from the interleukin-6 signal transducer gp130 equally well as does full-length Stat3. We conclude that, dependent on the cell type, different mechanisms allow Stat3 to regulate target gene transcription either with or without involvement of its putative carboxy-terminal transactivation domain.

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