scholarly journals Intestinal Recruitment of CCR6-Expressing Th17 Cells By Suppressing miR-681 Alleviates Endotoxemia-Induced Intestinal Injury And Reduces Mortality

2021 ◽  
Author(s):  
Liwen Gu ◽  
Jie Jiang ◽  
Zhigang Liu ◽  
Qiangqiang Liu ◽  
Jinli Liao ◽  
...  
Keyword(s):  
Bacterial Translocation ◽  
Knockout Mice ◽  
Th17 Cells ◽  
Intestinal Inflammation ◽  
Pathological Condition ◽  
Hypoxia Inducible Factor ◽  
Intestinal Injury ◽  
Luciferase Reporter ◽  
Ambiguous Function

Abstract BackgroundSepsis or endotoxemia can induce intestinal dysfunction in the epithelial and immune barrier. Th17 cells, a distinct subset of CD4+ T-helper cells, act as “border patrol” in the intestine under pathological condition and in the previous studies, Th17 cells exhibited an ambiguous function in intestinal inflammation. Our study will explore a specific role of Th17 cells and its relevant mechanism in endotoxemia-induced intestinal injury.MethodsLipopolysaccharide was used to establish mouse model of endotoxemia. miR-681 was analyzed by RT-PCR and northern blot analysis and its regulation by HIF-1α was determined by chromatin immunoprecipitation and luciferase reporter assay. Intestinal Th17 cells isolated from endotoxemic mice were quantitatively evaluated by flow cytometry and its recruitment to the intestine controlled by miR-681/CCR6 pathway was assessed by using anti-miRNA treatment and CCR6 knockout mice. Intestinal histopathology, villus length, intestinal inflammation, intestinal permeability, bacterial translocation and survival were investigated, by histology and TUNEL analysis, ELISA, measurement of diamine oxidase, bacterial culture, with or without anti-miR-681 treatment in endotoxemic wild-type and (or) CCR6 knockout mice.ResultsIn this study, we found that miR-681 was significantly promoted in intestinal Th17 cells during endotoxemia, which was dependent on hypoxia-inducible factor-1α (HIF-1α). Interestingly, miR-681 could directly suppress CCR6, which was a critical modulator for Th17 cell recruitment to the intestines. In vivo, anti-miR-681 enhanced survival, increased number of intestinal Th17 cells, reduced crypt and villi apoptosis, decreased intestinal inflammation and bacterial translocation, resulting in protection against endotoxemia-induced intestinal injury in mice. However, CCR6 deficiency could neutralize the beneficial effect of anti-miR-681 on the intestine during endotoxemia, suggesting that the increment of intestinal Th17 cells caused by anti-miR-681 relies on CCR6 expression. ConclusionThe results of the study indicate that control of intestinal Th17 cells by regulating novel miR-681/CCR6 signaling attenuates endotoxemia-induced intestinal injury.

scholarly journals Preoperative administration of the 5-HT4 receptor agonist prucalopride reduces intestinal inflammation and shortens postoperative ileus via cholinergic enteric neurons

Gut ◽  
2018 ◽  
Vol 68 (8) ◽  
pp. 1406-1416 ◽  
Author(s):  
Nathalie Stakenborg ◽  
Evelien Labeeuw ◽  
Pedro J Gomez-Pinilla ◽  
Sebastiaan De Schepper ◽  
Raymond Aerts ◽  
...  
Keyword(s):  
Knockout Mice ◽  
Postoperative Ileus ◽  
Intestinal Inflammation ◽  
Electrical Field Stimulation ◽  
Enteric Neurons ◽  
Postoperative Treatment ◽  
Wild Type ◽  
Clinical Recovery ◽  
Preoperative Administration

ObjectivesVagus nerve stimulation (VNS), most likely via enteric neurons, prevents postoperative ileus (POI) by reducing activation of alpha7 nicotinic receptor (α7nAChR) positive muscularis macrophages (mMφ) and dampening surgery-induced intestinal inflammation. Here, we evaluated if 5-HT4 receptor (5-HT4R) agonist prucalopride can mimic this effect in mice and human.DesignUsing Ca2+ imaging, the effect of electrical field stimulation (EFS) and prucalopride was evaluated in situ on mMφ activation evoked by ATP in jejunal muscularis tissue. Next, preoperative and postoperative administration of prucalopride (1–5 mg/kg) was compared with that of preoperative VNS in a model of POI in wild-type and α7nAChR knockout mice. Finally, in a pilot study, patients undergoing a Whipple procedure were preoperatively treated with prucalopride (n=10), abdominal VNS (n=10) or sham/placebo (n=10) to evaluate the effect on intestinal inflammation and clinical recovery of POI.ResultsEFS reduced the ATP-induced Ca2+ response of mMφ, an effect that was dampened by neurotoxins tetrodotoxin and ω-conotoxin and mimicked by prucalopride. In vivo, prucalopride administered before, but not after abdominal surgery reduced intestinal inflammation and prevented POI in wild-type, but not in α7nAChR knockout mice. In humans, preoperative administration of prucalopride, but not of VNS, decreased Il6 and Il8 expression in the muscularis externa and improved clinical recovery.ConclusionEnteric neurons dampen mMφ activation, an effect mimicked by prucalopride. Preoperative, but not postoperative treatment with prucalopride prevents intestinal inflammation and shortens POI in both mice and human, indicating that preoperative administration of 5-HT4R agonists should be further evaluated as a treatment of POI.Trial registration numberNCT02425774.

scholarly journals Hypoxia Preconditioning of Human MSCs: a Direct Evidence of HIF-1α and Collagen Type XV Correlation

2018 ◽  
Vol 51 (5) ◽  
pp. 2237-2249 ◽  
Author(s):  
Elisabetta Lambertini ◽  
Letizia Penolazzi ◽  
Marco Angelozzi ◽  
Leticia Scussel Bergamin ◽  
Cristina Manferdini ◽  
...  
Keyword(s):  
Collagen Type ◽  
Therapeutic Potential ◽  
Hypoxia Inducible Factor ◽  
Culture Conditions ◽  
Luciferase Reporter ◽  
Osteogenic Potential ◽  
Human Mscs ◽  
Short Period ◽  
Hypoxia Preconditioning

Background/Aims: Mesenchymal stromal cells (MSCs) hold considerable promise in bone tissue engineering, but their poor survival and potency when in vivo implanted limits their therapeutic potential. For this reason, the study on culture conditions and cellular signals that can influence the potential therapeutic outcomes of MSCs have received considerable attention in recent years. Cell maintenance under hypoxic conditions, in particular for a short period, is beneficial for MSCs, as low O2 tension is similar to that present in the physiologic niche, however the precise mechanism through which hypoxia preconditioning affects these cells remains unclear. Methods: In order to explore what happens during the first 48 h of hypoxia preconditioning in human MSCs (hMSCs) from bone marrow, the cells were exposed to 1.5% O2 tension in the X3 Hypoxia Hood and Culture Combo – Xvivo System device. The expression modulation of critical genes which could be good markers of increased osteopotency has been investigated by Western blot, immunufluorescence and ELISA. Luciferase reporter assay and Chromatin immunoprecipitation was used to investigate the regulation of the expression of Collagen type XV (ColXV) gene. Results: We identified ColXV as a new low O2 tension sensitive gene, and provided a novel mechanistic evidence that directly HIF-1α (hypoxia-inducible factor-1 alpha) mediates ColXV expression in response to hypoxia, since it was found specifically in vivo recruited at ColXV promoter, in hypoxia-preconditioned hMSCs. This finding, together the evidence that also Runx2, VEGF and FGF-2 expression increased in hypoxia preconditioned hMSCs, is consistent with the possibility that increased ColXV expression in response to hypoxia is mediated by an early network that supports the osteogenic potential of the cells. Conclusion: These results add useful information to understand the role of a still little investigated collagen such as ColXV, and identify ColXV as a marker of successful hypoxia preconditioning. As a whole, our data give further evidence that hypoxia preconditioned hMSCs have greater osteopotency than normal hMSCs, and that the effects of hypoxic regulation of hMSCs activities should be considered before they are clinically applied.

scholarly journals Induction of Redox-Active Gene Expression by CoCl2 Ameliorates Oxidative Stress-Mediated Injury of Murine Auditory Cells

Antioxidants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 399 ◽  
Author(s):  
Jhang Ho Pak ◽  
Junyeong Yi ◽  
Sujin Ryu ◽  
In Ki Kim ◽  
Jung-Woong Kim ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Ganglion Cells ◽  
Stria Vascularis ◽  
Hypoxia Inducible Factor ◽  
Spiral Ganglion ◽  
Organ Of Corti ◽  
Luciferase Reporter ◽  
Related Factor ◽  
Redox Active

Free radicals formed in the inner ear in response to high-intensity noise, are regarded as detrimental factors for noise-induced hearing loss (NIHL). We reported previously that intraperitoneal injection of cobalt chloride attenuated the loss of sensory hair cells and NIHL in mice. The present study was designed to understand the preconditioning effect of CoCl2 on oxidative stress-mediated cytotoxicity. Treatment of auditory cells with CoCl2 promoted cell proliferation, with increases in the expressions of two redox-active transcription factors (hypoxia-inducible factor 1α, HIF-1α, nuclear factor erythroid 2-related factor 2; Nrf-2) and an antioxidant enzyme (peroxiredoxin 6, Prdx6). Hydrogen peroxide treatment resulted in the induction of cell death and reduction of these protein expressions, reversed by pretreatment with CoCl2. Knockdown of HIF-1α or Nrf-2 attenuated the preconditioning effect of CoCl2. Luciferase reporter analysis with a Prdx6 promoter revealed transactivation of Prdx6 expression by HIF-1α and Nrf-2. The intense immunoreactivities of HIF-1α, Nrf-2, and Prdx6 in the organ of Corti (OC), spiral ganglion cells (SGC), and stria vascularis (SV) of the cochlea in CoCl2-injected mice suggested CoCl2-induced activation of HIF-1α, Nrf-2, and Prdx6 in vivo. Therefore, we revealed that the protective effect of CoCl2 is achieved through distinctive signaling mechanisms involving HIF-1α, Nrf-2, and Prdx6.

scholarly journals Activin-A limits Th17 pathogenicity and autoimmune neuroinflammation via CD39 and CD73 ectonucleotidases and Hif1-α–dependent pathways

2020 ◽  
Vol 117 (22) ◽  
pp. 12269-12280 ◽  
Author(s):  
Ioannis Morianos ◽  
Aikaterini I. Trochoutsou ◽  
Gina Papadopoulou ◽  
Maria Semitekolou ◽  
Aggelos Banos ◽  
...  
Keyword(s):  
Th17 Cell ◽  
Th17 Cells ◽  
Hypoxia Inducible Factor ◽  
Activin A ◽  
Autoimmune Encephalomyelitis ◽  
Cns Inflammation ◽  
Functional Studies ◽  
Aryl Hydrocarbon ◽  
And Control

In multiple sclerosis (MS), Th17 cells are critical drivers of autoimmune central nervous system (CNS) inflammation and demyelination. Th17 cells exhibit functional heterogeneity fostering both pathogenic and nonpathogenic, tissue-protective functions. Still, the factors that control Th17 pathogenicity remain incompletely defined. Here, using experimental autoimmune encephalomyelitis, an established mouse MS model, we report that therapeutic administration of activin-A ameliorates disease severity and alleviates CNS immunopathology and demyelination, associated with decreased activation of Th17 cells. In fact, activin-A signaling through activin-like kinase-4 receptor represses pathogenic transcriptional programs in Th17-polarized cells, while it enhances antiinflammatory gene modules. Whole-genome profiling and in vivo functional studies revealed that activation of the ATP-depleting CD39 and CD73 ectonucleotidases is essential for activin-A–induced suppression of the pathogenic signature and the encephalitogenic functions of Th17 cells. Mechanistically, the aryl hydrocarbon receptor, along with STAT3 and c-Maf, are recruited to promoter elements onEntpd1andNt5e(encoding CD39 and CD73, respectively) and other antiinflammatory genes, and control their expression in Th17 cells in response to activin-A. Notably, we show that activin-A negatively regulates the metabolic sensor, hypoxia-inducible factor-1α, and key inflammatory proteins linked to pathogenic Th17 cell states. Of translational relevance, we demonstrate that activin-A is induced in the CNS of individuals with MS and restrains human Th17 cell responses. These findings uncover activin-A as a critical controller of Th17 cell pathogenicity that can be targeted for the suppression of autoimmune CNS inflammation.

scholarly journals Vitamin D receptor pathway is required for probiotic protection in colitis

2015 ◽  
Vol 309 (5) ◽  
pp. G341-G349 ◽  
Author(s):  
Shaoping Wu ◽  
Sonia Yoon ◽  
Yong-Guo Zhang ◽  
Rong Lu ◽  
Yinglin Xia ◽  
...  
Keyword(s):  
Vitamin D ◽  
Vitamin D Receptor ◽  
Knockout Mice ◽  
Target Genes ◽  
Lactobacillus Rhamnosus ◽  
Luciferase Reporter ◽  
Transcriptional Level ◽  
Probiotic Treatment

Low expression of vitamin D receptor (VDR) and dysfunction of vitamin D/VDR signaling are reported in patients with inflammatory bowel disease (IBD); therefore, restoration of VDR function to control inflammation in IBD is desirable. Probiotics have been used in the treatment of IBD. However, the role of probiotics in the modulation of VDR signaling to effectively reduce inflammation is unknown. We identified a novel role of probiotics in activating VDR activity, thus inhibiting inflammation, using cell models and VDR knockout mice. We found that the probiotics Lactobacillus rhamnosus strain GG (LGG) and Lactobacillus plantarum (LP) increased VDR protein expression in both mouse and human intestinal epithelial cells. Using the VDR luciferase reporter vector, we detected increased transcriptional activity of VDR after probiotic treatment. Probiotics increased the expression of the VDR target genes, such as antimicrobial peptide cathelicidin, at the transcriptional level. Furthermore, the role of probiotics in regulating VDR signaling was tested in vivo using a Salmonella-colitis model in VDR knockout mice. Probiotic treatment conferred physiological and histologic protection from Salmonella-induced colitis in VDR+/+mice, whereas probiotics had no effects in the VDR−/−mice. Probiotic treatment also enhanced numbers of Paneth cells, which secrete AMPs for host defense. These data indicate that the VDR pathway is required for probiotic protection in colitis. Understanding how probiotics enhance VDR signaling and inhibit inflammation will allow probiotics to be used effectively, resulting in innovative approaches to the prevention and treatment of chronic inflammation.

scholarly journals Roxadustat (FG4592) alleviates Radiation-Induced Intestinal Injury by facilitating recovery of intestinal stem cell and reducing damage of intestinal epithelial cell

2020 ◽  
Author(s):  
Penglin Xia ◽  
Yajie Yang ◽  
Ruling Liu ◽  
Haibo Tang ◽  
Jicong Du ◽  
...  
Keyword(s):  
Hypoxia Inducible Factor ◽  
Protective Role ◽  
Intestinal Injury ◽  
Intestinal Epithelial ◽  
Brdu Label ◽  
Retroperitoneal Tumors ◽  
Radiation Induced ◽  
Proliferation Potential

Abstract Background: Radiation induced-intestinal injury (RIII) is a common complication after radiation therapy in patients with pelvic, abdominal or retroperitoneal tumors. The mechanism of RIII includes radiation-induced death of intestinal epithelial cells (IECs) and damage of intestinal stem cells (ISCs), among which damage of ISCs is main cause. Most recently, hypoxia Inducible factor (HIF) has been found to have effect on maintaining stemness and promoting proliferation of ISCs, which suggests a protective role of HIF in the RIII. In this study, we investigated the effect of FG4592, a novel up-regulator of HIF, on the protection of RIII, and further researched its function on ISCs.Methods: With/without FG4592 treatment, the abdomen of mice was radiated at dose of 25Gy, and then the degree of intestinal injury was assessed by H&E staining and Brdu label. By intestinal organoid culture, the multiplication capacity and differentiation features of ISCs were detected. Besides, the effects of FG4592 on the radiated IECs were also evaluated by detecting cell viability, apoptosis, and proliferation potential.Results: FG4592 could effectively up-regulate the expression of HIF-1α and HIF-2α in vivo. An abdominal radiation of 25Gy established the RIII model of mice, by which FG4592 was verified to have protective effect on the intestine from radiation. Morphology and Brdu test of intestinal organoid showed that FG4592 could promote regeneration and differentiation in ISCs after radiation, which were mediated by up-regulating HIF-2 rather than HIF-1.Conclusion: FG4592, a novel up-regulator of HIF could remit RIII and promote regeneration and differentiation of ISCs after radiation, which were depend on HIF-2 rather than HIF-1.

scholarly journals A Potential Probiotic for Diarrhea: Clostridium tyrobutyricum Protects Against LPS-Induced Epithelial Dysfunction via IL-22 Produced By Th17 Cells in the Ileum

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhiping Xiao ◽  
Lujie Liu ◽  
Xun Pei ◽  
Wanjing Sun ◽  
Yuyue Jin ◽  
...  
Keyword(s):  
Th17 Cells ◽  
Intestinal Inflammation ◽  
Flow Cytometric Analysis ◽  
Protective Role ◽  
Regulatory Function ◽  
Clostridium Tyrobutyricum ◽  
Dependent Manner ◽  
Protective Function

Probiotics are clinically used for diarrhea and inflammatory bowel diseases in both humans and animals. Previous studies have shown that Clostridium tyrobutyricum (Ct) protects against intestinal dysfunction, while its regulatory function in the gut needs further investigation and the related mechanisms are still not fully elucidated. This study aims to further verify the protective function of Ct and reveal its underlying mechanisms in alleviating diarrhea and intestinal inflammation. Ct inhibited LPS-induced diarrhea and intestinal inflammation in the ileum. IL-22 was identified and the protective role of Ct in the ileum presented an IL-22-dependent manner according to the transcriptomic analysis and in vivo interference mice experiments. The flow cytometric analysis of immune cells in the ileum showed that Ct enhanced the proportions of Th17 cells in response to LPS. The results of in situ hybridization further verified that Ct triggered Th17 cells to produce IL-22, which combined with IL-22RA1 expressed in the epithelial cells. Moreover, Ct was unable to enhance the levels of short-chain fatty acids (SCFAs) in the ileum, suggesting that the protective role of Ct in the ileum was independent of SCFAs. This study uncovered the role of Ct in alleviating diarrhea and inflammation with the mechanism of stimulating Th17 cells in the lamina propria to produce IL-22, highlighting its potential application as a probiotic for diarrhea and inflammation in the ileum.

Erythroid Kruppel-Like Factor Regulates E2F4 and the G1 Cdk Inhibitor, p18.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1357-1357
Author(s):  
Andrew C. Perkins ◽  
Janelle R. Keys ◽  
Denise J. Hodge ◽  
Michael R. Tallack
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Transcription Factor ◽  
Knockout Mice ◽  
Fetal Liver ◽  
Transcriptional Profiling ◽  
Globin Gene ◽  
Luciferase Reporter ◽  
Cdk Inhibitor

Abstract Erythroid Kruppel-Like Factor (EKLF) is a zinc finger transcription factor which is essential for β-globin gene expression. Knockout mice die from anemia at E15, but restoration of globin chain imbalance does not rescue anemia or increase survival. Cell lines derived from EKLF null mice undergo proliferation arrest upon reactivation of a conditional EKLF-ER fusion protein, suggesting a role in cell cycle control. A transcriptional profiling experiment comparing the global gene expression in EKLF null and wild type fetal liver identified many differentially expressed genes, a number of which function in G1 and at the G1/S checkpoint of the cell cycle. The Cyclin dependent kinase (Cdk) inhibitor, p18, and the S phase transcription factor E2F4 were both found to be significantly down regulated in EKLF null mice and this result was confirmed by real-time PCR. Interestingly, E2F4 knockout mice have a similar phenotype to EKLF knockout mice. Bioinformatic searches of the p18 and E2F4 genes shows that each contains phylogenetically conserved CACC box motifs capable of binding EKLF within longer regions of conservation in promoter and intron regions. The p18 gene contains two conserved CACCC sites upstream of the start of transcription, which are required for EKLF dependent promoter activity in luciferase reporter assays. The transcription factor E2F4 contains a conserved EKLF-binding CACC site within an intron that is closely associated with two conserved GATA1 binding sites. We show by a chromatin immunoprecipitation (ChIP) assays that the E2F4 intron and p18 promoter are occupied by EKLF in vivo. Together, these results suggest that EKLF is likely to directly regulate expression of key cell cycle genes in vivo to drive the switch from proliferation to differentiation of erythrocytes. The loss of EKLF is likely to result in aberrant proliferation and predisposition to leukemia.

scholarly journals Circular RNA CircMAP3K5 Acts as a MicroRNA-22-3p Sponge to Promote Resolution of Intimal Hyperplasia via TET2-Mediated SMC Differentiation

Circulation ◽  
2020 ◽  
Author(s):  
Zhi Zeng ◽  
Luoxing Xia ◽  
Shunyang Fan ◽  
Junmeng Zheng ◽  
Jinhong Qin ◽  
...  
Keyword(s):  
Rna Sequencing ◽  
Knockout Mice ◽  
Intimal Hyperplasia ◽  
Neointimal Hyperplasia ◽  
Circular Rna ◽  
Luciferase Reporter ◽  
Sequencing Data ◽  
Aberrant Expression ◽  
Proliferative Effect

Background: Aberrant expression of circular RNA (CircRNA) contributes to human diseases. CircRNAs regulate gene expression by sequestering specific microRNAs (miRNAs). In this study, we investigated whether CircMAP3K5 could act as a competing endogenous miR-22-3p sponge and regulate neointimal hyperplasia. Methods: CircRNA profiling from genome-wide RNA sequencing data was compared between human coronary artery smooth muscle cells (HCASMCs) treated with or without PDGF. Expression levels of circular MAP3K5 (CircMAP3K5) was assessed in human coronary arteries from autopsies on patients with dilated cardiomyopathy (DCM) or coronary heart disease (CHD). The role of CircMAP3K5 in intimal hyperplasia was further investigated in mice with AAV9-mediated CircMAP3K5 transfection. SMC-specific Tet2 knockout mice and global miR-22-3p knockout mice were used to delineate the mechanism by which CircMAP3K5 attenuated neointimal hyperplasia using the femoral arterial wire injury model. Results: RNA sequencing demonstrated that treatment with PDGF-BB significantly reduced expression of CircMAP3K5 in HCASMCs. Wire-injured mouse femoral arteries and diseased arteries from CHD patients (where PDGF-BB is increased) confirmed in vivo downregulation of CircMAP3K5 associated with injury and disease. Lentivirus-mediated overexpression of CircMAP3K5 inhibited the proliferation of HCASMCs. In vivo AAV9-mediated transfection of CircMap3k5 specifically inhibited SMC proliferation in the wire-injured mouse arteries, resulting in reduced neointima formation. Using a luciferase reporter assay and RNA pull-down, CircMAP3K5 was found to sequester miR-22-3p, which in turn inhibited the expression of TET2. Both in vitro and in vivo results demonstrate that the loss of miR-22-3p recapitulated the anti-proliferative effect of CircMap3k5 on VSMCs. In SMC-specific Tet2 knockout mice, loss of Tet2 abolished the CircMap3k5-mediated anti-proliferative effect on VSMCs. Conclusions: We identify CircMAP3K5 as a master regulator of TET2-mediated VSMC differentiation. Targeting the CircMAP3K5/miR-22-3p/TET2 axis may provide a potential therapeutic strategy for diseases associated with intimal hyperplasia including restenosis and atherosclerosis.

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