Dataset Information

Endotoxemia Induces I?B?/NF-?B-Dependent Endothelin-1 Expression in Hepatic Macrophages.

ABSTRACT: Elevated serum concentrations of the vasoactive protein endothelin-1 (ET-1) occur in the setting of systemic inflammatory response syndrome and contribute to distal organ hypoperfusion and pulmonary hypertension. Thus, understanding the cellular source and transcriptional regulation of systemic inflammatory stress-induced ET-1 expression may reveal therapeutic targets. Using a murine model of LPS-induced septic shock, we demonstrate that the hepatic macrophage is the primary source of elevated circulating ET-1, rather than the endothelium as previously proposed. Using pharmacologic inhibitors, ET-1 promoter luciferase assays, and by silencing and overexpressing NF-?B inhibitory protein I?B expression, we demonstrate that LPS-induced ET-1 expression occurs via an NF-?B-dependent pathway. Finally, the specific role of the cRel/p65 inhibitory protein I?B? was evaluated. Although cytoplasmic I?B? inhibits activity of cRel-containing NF-?B dimers, nuclear I?B? stabilizes NF-?B/DNA binding and enhances gene expression. Using targeted pharmacologic therapies to specifically prevent I?B?/NF-?B signaling, as well as mice genetically modified to overexpress I?B?, we show that nuclear I?B? is both necessary and sufficient to drive LPS-induced ET-1 expression. Together, these results mechanistically link the innate immune response mediated by I?B?/NF-?B to ET-1 expression and potentially reveal therapeutic targets for patients with Gram-negative septic shock.

SUBMITTER: McKenna S

PROVIDER: S-EPMC4730915 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Endotoxemia Induces IκBβ/NF-κB-Dependent Endothelin-1 Expression in Hepatic Macrophages.

McKenna Sarah S Gossling Megan M Bugarini Alejandro A Hill Elizabeth E Anderson Aimee L AL Rancourt Raymond C RC Balasubramaniyan Natarajan N El Kasmi Karim C KC Wright Clyde J CJ

Journal of immunology (Baltimore, Md. : 1950) 20150904 8

Elevated serum concentrations of the vasoactive protein endothelin-1 (ET-1) occur in the setting of systemic inflammatory response syndrome and contribute to distal organ hypoperfusion and pulmonary hypertension. Thus, understanding the cellular source and transcriptional regulation of systemic inflammatory stress-induced ET-1 expression may reveal therapeutic targets. Using a murine model of LPS-induced septic shock, we demonstrate that the hepatic macrophage is the primary source of elevated c ...[more]

PMID: 26342031

Similar Datasets

Project description:Background:Tumor-associated macrophage (TAM) is emerging as one of the important complications in cancer promotion. Interleukin-17 (IL-17), a potent pro-inflammatory cytokine, plays an active role in promoting M2 macrophage differentiation (TAMs are M2-like phenotypes). In this study, we aimed to evaluate that IL-17 stimulates key phenotypic and functional signatures of M2 macrophages associated with cancer progression in non-small-cell lung cancer (NSCLC) patients. Patients and methods:The markers and cytokines of M2 macrophages were detected in THP-1-derived macrophages and mouse peritoneal macrophages treated with IL-17. The activation of nuclear factor kappa B (NF-?B) and nuclear localization of p65 in IL-17-treated cells were investigated. The BAY11-7082 inhibitor and the siRNA of p65 were used to block the NF-?B activation. A total of 85 patients who underwent surgery for histologically verified NSCLC were enrolled in this study. The expression of IL-17 and M2 macrophage markers were assessed by immunostaining. Survivals were estimated using the Kaplan-Meier method. Results:The CD163 and CD206 cell surface markers and transforming growth factor beta (TGF-?), vascular endothelial growth factor (VEGF) and IL-10 of M2 macrophages were significantly increased in IL-17-treated THP-1-derived macrophages in a dose-dependent manner. IL-17 increased the mRNA levels of Arginase I and Fizz1, the phosphorylation of IkB? and nuclear localization of p65 (a subunit of NF-?B). The BAY11-7082 abrogated IL-17-induced CD206 and CD163 expression, TGF-?, VEGF, IL-10, Arginase I and Fizz1 expression and p65 nuclear translocation. Further experiments showed that IL-17 induced the expression of CD206, CD163, Arginase I, Fizz1 and Ym1 in mouse peritoneal macrophages that were inhibited by siRNA of p65. The immunostaining experiments on human NSCLC tissues indicated that high IL-17 expression was significantly correlated with CD163 and c-Maf. The intratumoral IL-17+ CD163+ c-Maf+ cells were associated with NSCLC progression. Conclusion:IL-17 stimulated macrophages to M2-like phenotypes via NF-?B activation. IL-17 may be a potential therapeutic target for NSCLC.

Project description:BackgroundSelenium (Se) levels decrease in the circulation during acute inflammatory states and sepsis, and are inversely associated with morbidity and mortality. A more specific understanding of where selenoproteins and Se processing are compromised during insult is needed. We investigated the acute signaling response in selenoenzymes and Se processing machinery in multiple organs after innate immune activation in response to systemic lipopolysaccharide (LPS).MethodsWild type (WT) adult male C57/B6 mice were exposed to LPS (5 mg/kg, intraperitoneal). Blood, liver, lung, kidney and spleen were collected from control mice as well as 2, 4, 8, and 24 h after LPS. Plasma Se concentration was determined by ICP-MS. Liver, lung, kidney and spleen were evaluated for mRNA and protein content of selenoenzymes and proteins required to process Se.ResultsAfter 8 h of endotoxemia, plasma levels of Se and the Se transporter protein, SELENOP were significantly decreased. Consistent with this timing, the transcription and protein content of several hepatic selenoenzymes, including SELENOP, glutathione peroxidase 1 and 4 were significantly decreased. Furthermore, hepatic transcription and protein content of factors required for the Se processing, including selenophosphate synthetase 2 (Sps2), phosphoseryl tRNA kinase (Pstk), selenocysteine synthase (SepsecS), and selenocysteine lyase (Scly) were significantly decreased. Significant LPS-induced downregulation of these key selenium processing enzymes was observed in isolated hepatocytes. In contrast to the acute and dynamic changes observed in the liver, selenoenzymes did not decrease in the lung, kidney or spleen.ConclusionHepatic selenoenzyme production and Se processing factors decreased after endotoxemia. This was temporally associated with decreased circulating Se. In contrast to these active changes in the regulation of Se processing in the liver, selenoenzymes did not decrease in the lung, kidney or spleen. These findings highlight the need to further study the impact of innate immune challenges on Se processing in the liver and the impact of targeted therapeutic Se replacement strategies during innate immune challenge.

Dataset Information

Endotoxemia Induces I?B?/NF-?B-Dependent Endothelin-1 Expression in Hepatic Macrophages.

Publications

Endotoxemia Induces IκBβ/NF-κB-Dependent Endothelin-1 Expression in Hepatic Macrophages.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets