STAT3 regulates NF-κB recruitment to the IL-12p40 promoter in dendritic cells

Blood ◽  
2005 ◽  
Vol 105 (2) ◽  
pp. 689-696 ◽  
Author(s):  
Frank Hoentjen ◽  
R. Balfour Sartor ◽  
Michitaka Ozaki ◽  
Christian Jobin
Keyword(s):  
Gene Expression ◽  
Dendritic Cells ◽  
Molecular Mechanisms ◽  
Intestinal Inflammation ◽  
Nuclear Translocation ◽  
Green Fluorescence Protein ◽  
Interleukin 10 ◽  
Mrna Accumulation ◽  
Stat3 Phosphorylation ◽  
Regulatory Effects

Abstract Interleukin-10-deficient (IL-10-/-) mice develop an IL-12-mediated intestinal inflammation in the absence of endogenous IL-10. The molecular mechanisms of the dysregulated IL-12 responses in IL-10-/- mice are poorly understood. In this study, we investigated the role of nuclear factor-κ B (NF-κB) and signal transducers and activators of transcription 3 (STAT3) in lipopolysaccharide (LPS)-induced IL-12p40 gene expression in bone marrow derived-dendritic cells (BMDCs) isolated from wild-type (WT) and IL-10-/- mice. We report higher IL-12p40 mRNA accumulation and protein secretion in LPS-stimulated BMDCs isolated from IL-10-/- compared with WT mice. LPS-induced NF-κB signaling is similar in IL-10-/- and WT BMDCs as measured by IκBα phosphorylation and degradation, RelA phosphorylation and nuclear translocation, and NF-κB transcriptional activity, with no down-regulatory effects of exogenous IL-10. Chromatin immunoprecipitation demonstrated enhanced NF-κB (cRel, RelA) binding to the IL-12p40 promoter in IL-10-/- but not WT BMDCs. Interestingly, LPS induced STAT3 phosphorylation in WT but not IL-10-/- BMDCs, a process blocked by IL-10 receptor blocking antibody. Adenoviral gene delivery of a constitutively active STAT3 but not control green fluorescence protein (GFP) virus blocked LPS-induced IL-12p40 gene expression and cRel recruitment to the IL-12p40 promoter. In conclusion, dysregulated LPS-induced IL-12p40 gene expression in IL-10-/- mice is due to enhanced NF-κB recruitment to the IL-12p40 promoter in the absence of activated STAT3.

scholarly journals A Novel Regulatory Axis, CHD1L-MicroRNA 486-Matrix Metalloproteinase 2, Controls Spermatogonial Stem Cell Properties

2018 ◽  
Vol 39 (4) ◽  
Author(s):  
Shan-Shan Liu ◽  
Eithne Margaret Maguire ◽  
Yin-Shan Bai ◽  
Li Huang ◽  
Yurong Liu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Stem Cell ◽  
Matrix Metalloproteinase ◽  
Molecular Mechanisms ◽  
Nuclear Translocation ◽  
Expression Profiles ◽  
Matrix Metalloproteinase 2 ◽  
Small Rna Sequencing ◽  
Growth Properties ◽  
The Matrix

ABSTRACT Spermatogonial stem cells (SSCs) are unipotent germ cells that are at the foundation of spermatogenesis and male fertility. However, the underlying molecular mechanisms governing SSC stemness and growth properties remain elusive. We have recently identified chromodomain helicase/ATPase DNA binding protein 1-like (Chd1l) as a novel regulator for SSC survival and self-renewal, but how these functions are controlled by Chd1l remains to be resolved. Here, we applied high-throughput small RNA sequencing to uncover the microRNA (miRNA) expression profiles controlled by Chd1l and showed that the expression levels of 124 miRNA transcripts were differentially regulated by Chd1l in SSCs. KEGG pathway analysis shows that the miRNAs that are differentially expressed upon Chd1l repression are significantly enriched in the pathways associated with stem cell pluripotency and proliferation. As a proof of concept, we demonstrate that one of the most highly upregulated miRNAs, miR-486, controls SSC stemness gene expression and growth properties. The matrix metalloproteinase 2 (MMP2) gene has been identified as a novel miR-486 target gene in the context of SSC stemness gene regulation and growth properties. Data from cotransfection experiments showed that Chd1l, miR-486, and MMP2 work in concert in regulating SSC stemness gene expression and growth properties. Finally, our data also revealed that MMP2 regulates SSC stemness gene expression and growth properties through activating β-catenin signaling by cleaving N-cadherin and increasing β-catenin nuclear translocation. Our data demonstrate that Chd1l–miR-486–MMP2 is a novel regulatory axis governing SSC stemness gene expression and growth properties, offering a novel therapeutic opportunity for treating male infertility.

scholarly journals Telmisartan improves myocardial remodeling by inhibiting leptin autocrine activity and activating PPARγ

2020 ◽  
Vol 245 (7) ◽  
pp. 654-666
Author(s):  
Hui Chen ◽  
Min Li ◽  
Lei Liu ◽  
Danjun Zhu ◽  
Gang Tian
Keyword(s):  
Molecular Mechanisms ◽  
Nuclear Translocation ◽  
Cardiac Fibroblasts ◽  
Left Ventricular ◽  
Collagen Metabolism ◽  
Myocardial Remodeling ◽  
Ang Ii ◽  
Metabolism Disorder ◽  
Ppar Γ ◽  
Stat3 Phosphorylation

The mechanism responsible for myocardial remodeling in hypertensive left ventricular hypertrophy (LVH) is complex. This study was designed to investigate the role of telmisartan in improving myocardial remodeling in hypertensive LVH and to explore the molecular mechanisms underlying the effects of telmisartan on hypertensive LVH. Hypertensive LVH was established in eight-week-old male Sprague–Dawley (SD) rats by abdominal aortic constriction. Telmisartan was intragastrically administered six weeks after surgery. Telmisartan improved cardiac dysfunction and myocardial fibrosis and reduced myocardial renin-angiotensin-aldosterone system (RAAS) activity and leptin levels in hypertensive LVH rats. To assess the mechanism underlying hypertensive LVH, cardiac fibroblasts were treated in vitro with angiotensin II (Ang II) or leptin, plus various inhibitors. Ang II stimulated leptin synthesis and secretion in cardiac fibroblasts by promoting AP-1 nuclear translocation via the AT1R-ROS-ERK1/2 pathway. Leptin induced collagen metabolism disorder in cardiac fibroblasts via the JAK2/STAT3 pathway. Telmisartan improved collagen metabolism disorder by inhibiting leptin induced by local Ang II in an autocrine manner. Telmisartan also improved Ang II-induced collagen metabolism disorder by inhibiting STAT3 phosphorylation, a leptin downstream signal, by activating PPAR-γ. Telmisartan therefore improved myocardial remodeling in hypertensive LVH rats by acting as an AT1R antagonist, inhibiting leptin autocrine activity induced by local Ang II and by acting as a PPAR-γ agonist, inhibiting downstream leptin activation of STAT3 phosphorylation. These findings indicate the crosstalk between local myocardial RAAS and leptin and suggest a molecular mechanism by which telmisartan improves myocardial remodeling in hypertensive LVH. Impact statement This study shows the crosstalk between local myocardial RAAS and leptin in hypertensive LVH rats; that Ang II induces myocardial remodeling by stimulating leptin autocrine activity by promoting AP-1 nuclear translocation via the AT1R-ROS-ERK1/2 pathway; and that telmisartan improves myocardial remodeling by inhibiting local Ang II-induced leptin autocrine activity and by inhibiting the leptin downstream signal STAT3 phosphorylation by activating PPAR-γ. These findings reveal novel molecular mechanisms by which telmisartan improves myocardial remodeling and could help to identify therapeutic targets for hypertensive LVH.

Probiotic modulation of dendritic cells and T cell responses in the intestine

2010 ◽  
Vol 1 (4) ◽  
pp. 317-326 ◽  
Author(s):  
M. Meijerink ◽  
J. Wells
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
Lamina Propria ◽  
Molecular Mechanisms ◽  
Intestinal Inflammation ◽  
T Cell Subsets ◽  
Host Recognition ◽  
Beneficial Effects ◽  
Immune Assays

Over the past decade it has become clear that probiotic and commensal interactions with mucosal dendritic cells in the lamina propria or epithelial cells lining the mucosa can modulate specific functions of the mucosal immune system. Innate pattern-recognition receptors such as TLRs, NLRs and CLRs play a crucial role in the host recognition of probiotics and other microorganism. Signalling via these receptors directly influences the chemokine and cytokine response of dendritic cells as well as the crosstalk between the epithelium and the immune cells in the lamina propria. This can influence the population of effector and regulatory T cell subsets in the mucosa. Immune assays with probiotics have shown that the in vitro immune response is both species and strain-specific. Such assays may be useful for the selection of probiotic strains that have beneficial effects on the regulation of intestinal inflammation but more comparative studies are needed to confirm recent findings. A better understanding of the molecular mechanisms of probiotics, the effect of dose, and frequency of administration on microbial sampling by mucosal APC will also help to clarify the value of immune assays as selection criteria for probiotics.

Indoleamine 2,3-dioxgenase-transfected mesenchymal stem cells suppress heart allograft rejection by increasing the production and activity of dendritic cells and regulatory T cells

2019 ◽  
Vol 68 (3) ◽  
pp. 728-737 ◽  
Author(s):  
Ji-Gang He ◽  
Bei-Bei Li ◽  
Liang Zhou ◽  
Dan Yan ◽  
Qiao-Li Xie ◽  
...  
Keyword(s):  
Stem Cells ◽  
T Cells ◽  
Mesenchymal Stem Cells ◽  
Dendritic Cells ◽  
Transforming Growth Factor Beta ◽  
Allograft Rejection ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Interleukin 10 ◽  
Heart Allograft

Expression of indoleamine 2,3-dioxygenase (IDO) in mesenchymal stem cells (MSC) is thought to contribute to MSC-mediated immunosuppression. A lentiviral-based transgenic system was used to generate bone marrow stem cells (BMSC) which stably expressed IDO (IDO-BMSCs). Coculture of IDO-BMSCs with dendritic cells (DC) or T cells was used to evaluate the immunomodulatory effect of IDO-BMSCs. A heterotopic heart transplant model in rats was used to evaluate allograft rejection after IDO-BMSC treatment. Mechanisms of IDO-BMSC-mediated immunosuppression were investigated by evaluating levels of proinflammatory and anti-inflammatory cytokines, and production of Tregs. A significant decrease in DC marker-positive cells and a significant increase in Tregs were observed in IDO-BMSC cocultured. Treatment of transplanted rats with IDO-BMSCs was associated with significantly prolonged graft survival. Compared with the control groups, transplanted animals treated with IDO-BMSCs had a (1) significantly higher ejection fraction and fractional shortening, (2) significantly lower expression of CD86, CD80, and MHCII, and significantly higher expression in CD274, and Tregs, and (3) significantly higher levels of interleukin-10 (IL-10), transforming growth factor beta-1 (TGF-β1), TGF-β2, and TGF-β3, and significantly lower levels of IL-2 and interferon gamma. Our results expand our understanding of the molecular mechanisms underlying suppression of heart allograft rejection via IDO-expressing BMSCs.

Differential effects of deoxycholic acid and taurodeoxycholic acid on NF-κB signal transduction and IL-8 gene expression in colonic epithelial cells

2004 ◽  
Vol 286 (6) ◽  
pp. G1000-G1008 ◽  
Author(s):  
M. Mühlbauer ◽  
B. Allard ◽  
A. K. Bosserhoff ◽  
S. Kiessling ◽  
H. Herfarth ◽  
...  
Keyword(s):  
Gene Expression ◽  
Signal Transduction ◽  
Epithelial Cells ◽  
Molecular Mechanisms ◽  
Deoxycholic Acid ◽  
Nuclear Translocation ◽  
Binding Activity ◽  
Dominant Negative ◽  
Dependent Manner ◽  
Colonic Epithelial Cells

Several effects of bile acids (BAs) on colonic epithelial cells (CECs) have been described, including induction of proliferation and apoptosis. Some of these effects are mediated through activation of the NF-κB transcriptional system. In this study, we investigated the molecular mechanisms underlying the BA-induced gene expression in CECs. The human CEC line HT-29 and primary human CECs were treated with dilutions of salts of deoxycholic acid (DCA) and taurodeoxycholic acid (TDCA). NF-κB binding activity was analyzed with EMSA, RelA translocation with immunofluorescence, and IκBα- and RelA-phosphorylation with Western blot analysis. IL-8 mRNA and protein expression were assessed by quantitative PCR and ELISA. Functional impact of NF-κB activation was determined by blocking the proteasome activity with MG132 or by preventing IKK activity with a dominant-negative IKKβ delivered by adenoviral dominant-negative (dn) IKKβ (Ad5dnIKKβ). DCA and TDCA induced IL-8 expression in a dose- and time-dependent manner. It is interesting that DCA but not TDCA induced IκBα-phophorylation, RelA translocation, and NF-κB binding activity. Accordingly, the proteasome inhibitor MG132 blocked DCA- but not TDCA-induced IL-8 gene expression. In contrast, TDCA-induced IL-8 gene expression correlated with enhanced RelA phosphorylation, which was blocked by Ad5dnIKKβ. Our data suggest that DCA-induced signal transduction mainly utilized the IκB degradation and RelA nuclear translocation pathway, whereas TDCA primarily induced IL-8 gene expression through RelA phosphorylation. These differences may have implications for the understanding of the pathophysiology of inflammation and carcinogenesis in the gut.

scholarly journals 15-Deoxy-△12,14-Prostaglandin J2 Promotes Resolution of Experimentally Induced Colitis

2021 ◽  
Vol 12 ◽  
Author(s):  
Wonki Kim ◽  
Jeong-Hoon Jang ◽  
Xiancai Zhong ◽  
Hyungseok Seo ◽  
Young-Joon Surh
Keyword(s):  
Arachidonic Acid ◽  
Colonic Mucosa ◽  
Molecular Mechanisms ◽  
Intestinal Inflammation ◽  
M1 Macrophages ◽  
Murine Colitis ◽  
Stat3 Phosphorylation ◽  
Prostaglandin D Synthase ◽  
Inflammatory Bowel ◽  
Experimentally Induced

Uncontrolled macrophage functions cause failure to resolve gut inflammation and has been implicated in the pathogenesis of inflammatory bowel disease (IBD). 15-Deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2), one of endogenous lipid mediators formed from arachidonic acid during the inflammatory process, has been reported to terminate inflammation. However, the pro-resolving effect of 15d-PGJ2 on intestinal inflammation and underlying molecular mechanisms remain largely unknown. In the present study, we examined the effects of 15d-PGJ2 on the resolution of dextran sulfate sodium (DSS)-induced murine colitis that mimics human IBD. Pharmacologic inhibition of prostaglandin D synthase (PGDS) responsible for the synthesis of 15d-PGJ2 hampered resolution of inflammation in the colonic mucosa of mice treated with DSS. Notably, intraperitoneal injection of 15d-PGJ2 accelerated the resolution of experimentally induced colitis. 15d-PGJ2 treatment reduced the number of neutrophils and M1 macrophages, while it increased the proportion of M2 macrophages. Moreover, 15d-PGJ2 treated mice exhibited the significantly reduced proportion of macrophages expressing the pro-inflammatory cytokine, IL-6 with concomitant suppression of STAT3 phosphorylation in the colonic mucosa of mice administered 2.5% DSS in drinking water. Taken together, these findings clearly indicate that 15d-PGJ2, endogenously generated from arachidonic acid by cyclooxygenase-2 and PGDS activities in inflamed tissue, promotes resolution of intestinal colitis.

scholarly journals Matrix Metalloproteinase-9 (MMP-9) induced disruption of intestinal epithelial tight junction barrier is mediated by NF-κB activation

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249544
Author(s):  
Rana Al-Sadi ◽  
Jessica Engers ◽  
Mohammad Haque ◽  
Steven King ◽  
Deemah Al-Omari ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Tight Junction ◽  
Intestinal Permeability ◽  
Barrier Function ◽  
Molecular Mechanisms ◽  
Intestinal Inflammation ◽  
Nuclear Translocation ◽  
Matrix Metalloproteinase 9 ◽  
Intestinal Epithelial ◽  
Metalloproteinase 9

Background Matrix Metalloproteinase-9 (MMP-9) has been shown to play a key role in mediating inflammation and tissue damage in inflammatory bowel disease (IBD). In patients with IBD, the intestinal tight junction (TJ) barrier is compromised as characterized by an increase in intestinal permeability. MMP-9 is elevated in intestinal tissue, serum and stool of patients with IBD. Previous studies from our laboratory showed that MMP-9 causes an increase in intestinal epithelial TJ permeability and that the MMP-9 induced increase in intestinal permeability is an important pathogenic factor contributing to the development of intestinal inflammation in IBD. However, the intracellular mechanisms that mediate the MMP-9 modulation of intestinal barrier function remain unclear. Aims The main aim of this study was to further elucidate the molecular mechanisms involved in MMP-9 induced increase in intestinal epithelial TJ permeability using Caco-2 monolayers as an in-vitro model system. Results MMP-9 induced increase in Caco-2 TJ permeability was associated with activation and cytoplasmic-to-nuclear translocation of NF-κB p65. Knocking-down NF-κB p65 by siRNA transfection prevented the MMP-9 induced expression of the NF-κB target gene IL-8, myosin light chain kinase (MLCK) protein expression, and subsequently prevented the increase in Caco-2 TJ permeability. In addition, the effect of MMP-9 on Caco-2 intestinal epithelial TJ barrier function was not mediated by apoptosis or necrosis. Conclusion Our data show that the MMP-9 induced disruption of Caco-2 intestinal epithelial TJ barrier function is regulated by NF-κB pathway activation of MLCK.

scholarly journals Distinct Functions of the Mitogen-activated Protein Kinase-activated Protein (MAPKAP) Kinases MK2 and MK3

2011 ◽  
Vol 286 (27) ◽  
pp. 24113-24124 ◽  
Author(s):  
Christian Ehlting ◽  
Natalia Ronkina ◽  
Oliver Böhmer ◽  
Ute Albrecht ◽  
Konrad A. Bode ◽  
...  
Keyword(s):  
Gene Expression ◽  
Protein Kinase ◽  
Nuclear Translocation ◽  
Interferon Regulatory Factor ◽  
Mitogen Activated Protein Kinase ◽  
Regulatory Factor ◽  
Interferon Regulatory Factor 3 ◽  
Downstream Signaling ◽  
Enhanced Expression ◽  
Regulatory Effects

In LPS-treated macrophages, activation of STAT3 is considered to be crucial for terminating the production of inflammatory cytokines. By analyzing the role of MAPK-activated protein kinase (MK) 2 and MK3 for LPS-induced STAT3 activation in macrophages, the present study provides evidence that MK2 is crucial for STAT3 activation in response to LPS because it prevents MK3 from impeding IFNβ gene expression. Accordingly, LPS-induced IFNβ gene expression is down-regulated in MK2-deficient macrophages and can be reconstituted by additional ablation of the MK3 gene in MK2/3−/− macrophages. This is in contrast to LPS-induced IL-10 expression, which essentially requires the presence of MK2. Further analysis of downstream signaling events involved in the transcriptional regulation of IFNβ gene expression suggests that, in the absence of MK2, MK3 impairs interferon regulatory factor 3 protein expression and activation and inhibits nuclear translocation of p65. This inhibition of p65 nuclear translocation coincides with enhanced expression and delayed degradation of IκBβ, whereas expression of IκBα mRNA and protein is impaired in the absence of MK2. The observation that siRNA directed against IκBβ is able to reconstitute IκBα expression in MK2−/− macrophages suggests that enhanced expression and delayed degradation of IκBβ and impaired NFκB-dependent IκBα expression are functionally linked. In summary, evidence is provided that MK2 regulates LPS-induced IFNβ expression and downstream STAT3 activation as it restrains MK3 from mediating negative regulatory effects on NFκB- and interferon regulatory factor 3-dependent LPS signaling.

scholarly journals CD83 increases MHC II and CD86 on dendritic cells by opposing IL-10–driven MARCH1-mediated ubiquitination and degradation

2011 ◽  
Vol 208 (1) ◽  
pp. 149-165 ◽  
Author(s):  
Lina E. Tze ◽  
Keisuke Horikawa ◽  
Heather Domaschenz ◽  
Debbie R. Howard ◽  
Carla M. Roots ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Mhc Class Ii ◽  
Molecular Mechanisms ◽  
Costimulatory Molecule ◽  
Class Ii ◽  
Interleukin 10 ◽  
Effective Vaccine ◽  
Vaccine Adjuvants ◽  
Mhc Ii ◽  
Tm Domain

Effective vaccine adjuvants must induce expression of major histocompatability (MHC) class II proteins and the costimulatory molecule CD86 on dendritic cells (DCs). However, some adjuvants elicit production of cytokines resulting in adverse inflammatory consequences. Development of agents that selectively increase MHC class II and CD86 expression without triggering unwanted cytokine production requires a better understanding of the molecular mechanisms influencing the production and degradation of MHC class II and CD86 in DCs. Here, we investigate how CD83, an immunoglobulin protein expressed on the surface of mature DCs, promotes MHC class II and CD86 expression. Using mice with an N-ethyl-N-nitrosourea–induced mutation eliminating the transmembrane (TM) region of CD83, we found that the TM domain of CD83 enhances MHC class II and CD86 expression by blocking MHC class II association with the ubiquitin ligase MARCH1. The TM region of CD83 blocks interleukin 10–driven, MARCH1-dependent ubiquitination and degradation of MHC class II and CD86 in DCs. Exploiting this posttranslational pathway for boosting MHC class II and CD86 expression on DCs may provide an opportunity to enhance the immunogenicity of vaccines.

Sign in / Sign up

Export Citation Format

Share Document