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1.
Am J Respir Crit Care Med ; 207(8): 998-1011, 2023 04 15.
Article in English | MEDLINE | ID: mdl-36724365

ABSTRACT

Rationale: Chronic obstructive pulmonary disease (COPD) is a disease characterized by persistent airway inflammation and disordered macrophage function. The extent to which alterations in macrophage bioenergetics contribute to impaired antioxidant responses and disease pathogenesis has yet to be fully delineated. Objectives: Through the study of COPD alveolar macrophages (AMs) and peripheral monocyte-derived macrophages (MDMs), we sought to establish if intrinsic defects in core metabolic processes drive macrophage dysfunction and redox imbalance. Methods: AMs and MDMs from donors with COPD and healthy donors underwent functional, metabolic, and transcriptional profiling. Measurements and Main Results: We observed that AMs and MDMs from donors with COPD display a critical depletion in glycolytic- and mitochondrial respiration-derived energy reserves and an overreliance on glycolysis as a source for ATP, resulting in reduced energy status. Defects in oxidative metabolism extend to an impaired redox balance associated with defective expression of the NADPH-generating enzyme, ME1 (malic enzyme 1), a known target of the antioxidant transcription factor NRF2 (nuclear factor erythroid 2-related factor 2). Consequently, selective activation of NRF2 resets the COPD transcriptome, resulting in increased generation of TCA cycle intermediaries, improved energetic status, favorable redox balance, and recovery of macrophage function. Conclusions: In COPD, an inherent loss of metabolic plasticity leads to metabolic exhaustion and reduced redox capacity, which can be rescued by activation of the NRF2 pathway. Targeting these defects, via NRF2 augmentation, may therefore present an attractive therapeutic strategy for the treatment of the aberrant airway inflammation described in COPD.


Subject(s)
NF-E2-Related Factor 2 , Pulmonary Disease, Chronic Obstructive , Humans , Macrophages/metabolism , NF-E2-Related Factor 2/metabolism , Oxidative Stress , Pulmonary Disease, Chronic Obstructive/metabolism , Pulmonary Disease, Chronic Obstructive/physiopathology , Malate Dehydrogenase/metabolism
3.
Nat Immunol ; 23(6): 927-939, 2022 06.
Article in English | MEDLINE | ID: mdl-35624205

ABSTRACT

Hypoxemia is a defining feature of acute respiratory distress syndrome (ARDS), an often-fatal complication of pulmonary or systemic inflammation, yet the resulting tissue hypoxia, and its impact on immune responses, is often neglected. In the present study, we have shown that ARDS patients were hypoxemic and monocytopenic within the first 48 h of ventilation. Monocytopenia was also observed in mouse models of hypoxic acute lung injury, in which hypoxemia drove the suppression of type I interferon signaling in the bone marrow. This impaired monopoiesis resulted in reduced accumulation of monocyte-derived macrophages and enhanced neutrophil-mediated inflammation in the lung. Administration of colony-stimulating factor 1 in mice with hypoxic lung injury rescued the monocytopenia, altered the phenotype of circulating monocytes, increased monocyte-derived macrophages in the lung and limited injury. Thus, tissue hypoxia altered the dynamics of the immune response to the detriment of the host and interventions to address the aberrant response offer new therapeutic strategies for ARDS.


Subject(s)
Lung Injury , Respiratory Distress Syndrome , Animals , Humans , Hypoxia/etiology , Inflammation/complications , Lung , Lung Injury/complications , Mice
4.
Wellcome Open Res ; 6: 38, 2021.
Article in English | MEDLINE | ID: mdl-33997298

ABSTRACT

Background: Acute respiratory distress syndrome (ARDS) is a severe critical condition with a high mortality that is currently in focus given that it is associated with mortality caused by coronavirus disease 2019 (COVID-19). Neutrophils play a key role in the lung injury characteristic of non-COVID-19 ARDS and there is also accumulating evidence of neutrophil mediated lung injury in patients who succumb to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods: We undertook a functional proteomic and metabolomic survey of circulating neutrophil populations, comparing patients with COVID-19 ARDS and non-COVID-19 ARDS to understand the molecular basis of neutrophil dysregulation. Results: Expansion of the circulating neutrophil compartment and the presence of activated low and normal density mature and immature neutrophil populations occurs in ARDS, irrespective of cause. Release of neutrophil granule proteins, neutrophil activation of the clotting cascade and upregulation of the Mac-1 platelet binding complex with formation of neutrophil platelet aggregates is exaggerated in COVID-19 ARDS. Importantly, activation of components of the neutrophil type I interferon responses is seen in ARDS following infection with SARS-CoV-2, with associated rewiring of neutrophil metabolism, and the upregulation of antigen processing and presentation. Whilst dexamethasone treatment constricts the immature low density neutrophil population, it does not impact upon prothrombotic hyperinflammatory neutrophil signatures. Conclusions: Given the crucial role of neutrophils in ARDS and the evidence of a disordered myeloid response observed in COVID-19 patients, this work maps the molecular basis for neutrophil reprogramming in the distinct clinical entities of COVID-19 and non-COVID-19 ARDS.

5.
PLoS One ; 15(7): e0232307, 2020.
Article in English | MEDLINE | ID: mdl-32667911

ABSTRACT

In the mammalian gut CD103+ve myeloid DCs are known to suppress inflammation threatened by luminal bacteria, but stimuli driving DC precursor maturation towards this beneficial phenotype are incompletely understood. We isolated CD11+ve DCs from mesenteric lymph nodes (MLNs) of healthy mice; CD103+ve DCs were 8-24 fold more likely than CD103-ve DCs to exhibit extensive of prior phagocytosis of apoptotic intestinal epithelial cells. However, CD103+ve and CD103-ve MLN DCs exhibited similar ex vivo capacity to ingest apoptotic cells, indicating that apoptotic cells might drive immature DC maturation towards the CD103+ve phenotype. When cultured with apoptotic cells, myeloid DC precursors isolated from murine bone marrow and characterised as lineage-ve CD103-ve, displayed enhanced expression of CD103 and ß8 integrin and acquired increased capacity to induce T regulatory lymphocytes (Tregs) after 7d in vitro. However, DC precursors isolated from αv-tie2 mice lacking αv integrins in the myeloid line exhibited reduced binding of apoptotic cells and complete deficiency in the capacity of apoptotic cells and/or latent TGF-ß1 to enhance CD103 expression in culture, whereas active TGF-ß1 increased DC precursor CD103 expression irrespective of αv expression. Fluorescence microscopy revealed clustering of αv integrin chains and latent TGF-ß1 at points of contact between DC precursors and apoptotic cells. We conclude that myeloid DC precursors can deploy αv integrin to orchestrate binding of apoptotic cells, activation of latent TGF-ß1 and acquisition of the immunoregulatory CD103+ve ß8+ve DC phenotype. This implies that a hitherto unrecognised consequence of apoptotic cell interaction with myeloid phagocytes is programming that prevents inflammation.


Subject(s)
Antigens, CD/metabolism , Apoptosis , Dendritic Cells/immunology , Gene Expression Regulation , Immunomodulation , Integrin alpha Chains/metabolism , Integrin alphaV/metabolism , Transforming Growth Factor beta1/metabolism , Animals , Dendritic Cells/cytology , Dendritic Cells/metabolism , Female , Mice, Inbred C57BL , Myeloid Cells/cytology , Phagocytosis , T-Lymphocytes, Regulatory/immunology
6.
J Clin Invest ; 130(6): 3221-3237, 2020 06 01.
Article in English | MEDLINE | ID: mdl-32191647

ABSTRACT

Neutrophilic inflammation is central to disease pathogenesis, for example, in chronic obstructive pulmonary disease, yet the mechanisms that retain neutrophils within tissues remain poorly understood. With emerging evidence that axon guidance factors can regulate myeloid recruitment and that neutrophils can regulate expression of a class 3 semaphorin, SEMA3F, we investigated the role of SEMA3F in inflammatory cell retention within inflamed tissues. We observed that neutrophils upregulate SEMA3F in response to proinflammatory mediators and following neutrophil recruitment to the inflamed lung. In both zebrafish tail injury and murine acute lung injury models of neutrophilic inflammation, overexpression of SEMA3F delayed inflammation resolution with slower neutrophil migratory speeds and retention of neutrophils within the tissues. Conversely, constitutive loss of sema3f accelerated egress of neutrophils from the tail injury site in fish, whereas neutrophil-specific deletion of Sema3f in mice resulted in more rapid neutrophil transit through the airways, and significantly reduced time to resolution of the neutrophilic response. Study of filamentous-actin (F-actin) subsequently showed that SEMA3F-mediated retention is associated with F-actin disassembly. In conclusion, SEMA3F signaling actively regulates neutrophil retention within the injured tissues with consequences for neutrophil clearance and inflammation resolution.


Subject(s)
Cell Movement/immunology , Membrane Proteins/immunology , Nerve Tissue Proteins/immunology , Neutrophils/immunology , Signal Transduction/immunology , Zebrafish Proteins/immunology , Zebrafish/immunology , Animals , Humans , Inflammation/immunology , Inflammation/pathology , Mice , Neutrophils/pathology , Up-Regulation/immunology
7.
Am J Pathol ; 190(6): 1224-1235, 2020 06.
Article in English | MEDLINE | ID: mdl-32201264

ABSTRACT

Intratracheal instillation of apoptotic cells enhances resolution of experimental lung inflammation by incompletely understood mechanisms. We report that this intervention induces functional regulatory T lymphocytes (Tregs) in mouse lung experimentally inflamed by intratracheal administration of lipopolysaccharide. Selective depletion demonstrated that Tregs were necessary for maximal apoptotic cell-directed enhancement of resolution, and adoptive transfer of additional Tregs was sufficient to promote resolution without administering apoptotic cells. After intratracheal instillation, labeled apoptotic cells were observed in most CD11c+CD103+ myeloid dendritic cells migrating to mediastinal draining lymph nodes and bearing migratory and immunoregulatory markers, including increased CCR7 and ß8 integrin (ITGB8) expression. In mice deleted for αv integrin in the myeloid line to reduce phagocytosis of dying cells by CD103+ dendritic cells, exogenous apoptotic cells failed to induce transforming growth factor-ß1 expression or Treg accumulation and failed to enhance resolution of lipopolysaccharide-induced lung inflammation. We conclude that in murine lung, myeloid phagocytes encountering apoptotic cells can deploy αv integrin-mediated mechanisms to induce Tregs and enhance resolution of acute inflammation.


Subject(s)
Apoptosis/physiology , Integrin alphaV/metabolism , Pneumonia/metabolism , T-Lymphocytes, Regulatory/metabolism , Adoptive Transfer , Animals , Forkhead Transcription Factors/metabolism , Lymphocyte Activation , Lymphocyte Depletion , Mice , Phagocytosis/physiology , Pneumonia/pathology
8.
Oncol Rep ; 43(2): 601-608, 2020 02.
Article in English | MEDLINE | ID: mdl-31894282

ABSTRACT

Receptor tyrosine kinase like orphan receptor 2 (ROR2) regulates Wnt5a-induced cell migration by phosphorylating PI3K/Akt and activating RhoA in osteosarcoma. However, the role of Wnt5a signaling and its corresponding receptors in the regulation of osteosarcoma metastasis remains poorly understood. ROR1 monoclonal antibody (mAb) and short hairpin (sh)RNA targeting ROR2 markedly inhibited the activity of dishevelled associated activator of morphogenesis 1 (DAAM1) and RhoA and retarded cell migration in osteosarcoma. ROR1 mAb and ROR2 shRNA destroyed the microfilament formation of osteosarcoma cells. Silencing of DAAM1 (with DAAM1 shRNA) downregulated RhoA activity and inhibited cell migration. The decrease of cell migration caused by DAAM1 shRNA was rescued by wild-type DAAM1 overexpression. DAAM1 and PI3Kα/Akt were parallel signaling pathways mediating osteosarcoma cell migration in response to Wnt5a. It was concluded that Wnt5a promotes osteosarcoma cell migration via ROR1/2 receptors, and then activates DAAM1 and RhoA.


Subject(s)
Bone Neoplasms/metabolism , Microfilament Proteins/metabolism , Osteosarcoma/metabolism , Receptor Tyrosine Kinase-like Orphan Receptors/metabolism , Wnt-5a Protein/metabolism , rho GTP-Binding Proteins/metabolism , Cell Line, Tumor , Cell Movement , Class Ia Phosphatidylinositol 3-Kinase/metabolism , Gene Expression Regulation, Neoplastic , Humans , Signal Transduction
9.
Oncoimmunology ; 8(8): 1608106, 2019.
Article in English | MEDLINE | ID: mdl-31413918

ABSTRACT

Immunization of patients with autologous, ex vivo matured dendritic cell (DC) preparations, in order to prime antitumor T-cell responses, is the focus of intense research. Despite progress and approval of clinical approaches, significant enhancement of these personalized immunotherapies is urgently needed to improve efficacy. We show that immunotherapeutic murine and human DC, generated in the presence of the antimicrobial host defense peptide LL-37, have dramatically enhanced expansion and differentiation of cells with key features of the critical CD103+/CD141+ DC subsets, including enhanced cross-presentation and co-stimulatory capacity, and upregulation of CCR7 with improved migratory capacity. These LL-37-DC enhanced proliferation, activation and cytokine production by CD8+ (but not CD4+) T cells in vitro and in vivo. Critically, tumor antigen-presenting LL-37-DC increased migration of primed, activated CD8+ T cells into established squamous cell carcinomas in mice, and resulted in tumor regression. This advance therefore has the potential to dramatically enhance DC immunotherapy protocols.

10.
Biosci Rep ; 39(5)2019 05 31.
Article in English | MEDLINE | ID: mdl-30967498

ABSTRACT

Objective: The senescence of nucleus pulposus (NP) cells induced by oxidative stress is one of the important causes of intervertebral disc degeneration (IDD). Herein, we investigated the role and action mechanism of silent information regulator 1 (SIRT1) in oxidative stress-induced senescence of rat NP cell.Methods: Premature senescence of rat NP cells was induced by sublethal concentration of hydrogen peroxide (H2O2) (100 µM). SIRT1 was activated with SRT1720 (5 µM) to explore its effect on NP cells senescence. FoxO1 and Akt were inhibited by AS1842856 (0.2 µM) and MK-2206 (5 µM), respectively, to explore the role of Akt-FoxO1-SIRT1 axis in rat NP cells. Pretreatment with the resveratrol (20 µM), a common antioxidant and indirect activator of SIRT1, was done to investigate its role in senescent rat NP cells.Results: The mRNA and protein levels of SIRT1 were decreased in H2O2-induced senescent rat NP cells, and that specific activation of SIRT1 suppresses senescence. And the Akt-FoxO1 pathway, as the upstream of SIRT1, might be involved in the regulation of H2O2-induced senescence of rat NP cells by affecting the expression of SIRT1. In addition, the resveratrol played an anti-senescence role in rat NP cells, which might affect the Akt-FoxO1-SIRT1 axis.Conclusion: SIRT1 ameliorated oxidative stress-induced senescence of rat NP cell which was regulated by Akt-FoxO1 pathway, and resveratrol exerted anti-senescence effects by affecting this signaling axis.


Subject(s)
Chondrocytes/drug effects , Hydrogen Peroxide/pharmacology , Nerve Tissue Proteins/genetics , Proto-Oncogene Proteins c-akt/genetics , Sirtuin 1/genetics , Animals , Antioxidants/pharmacology , Cell Cycle/drug effects , Cell Cycle/genetics , Cellular Senescence/drug effects , Chondrocytes/cytology , Chondrocytes/metabolism , Gene Expression Regulation , Heterocyclic Compounds, 4 or More Rings/pharmacology , Hydrogen Peroxide/antagonists & inhibitors , Nerve Tissue Proteins/antagonists & inhibitors , Nerve Tissue Proteins/metabolism , Nucleus Pulposus/cytology , Nucleus Pulposus/metabolism , Oxidative Stress , Primary Cell Culture , Proto-Oncogene Proteins c-akt/metabolism , Quinolones/pharmacology , Rats , Rats, Sprague-Dawley , Resveratrol/pharmacology , Signal Transduction , Sirtuin 1/metabolism
11.
Exp Mol Med ; 51(2): 1-14, 2019 02 13.
Article in English | MEDLINE | ID: mdl-30760699

ABSTRACT

Acute kidney injury (AKI) following ischemia-reperfusion injury (IRI) has a high mortality and lacks specific therapies. Here, we report that mice lacking kynurenine 3-monooxygenase (KMO) activity (Kmonull mice) are protected against AKI after renal IRI. We show that KMO is highly expressed in the kidney and exerts major metabolic control over the biologically active kynurenine metabolites 3-hydroxykynurenine, kynurenic acid, and downstream metabolites. In experimental AKI induced by kidney IRI, Kmonull mice had preserved renal function, reduced renal tubular cell injury, and fewer infiltrating neutrophils compared with wild-type (Kmowt) control mice. Together, these data confirm that flux through KMO contributes to AKI after IRI, and supports the rationale for KMO inhibition as a therapeutic strategy to protect against AKI during critical illness.


Subject(s)
Kidney Diseases/etiology , Kidney Diseases/metabolism , Kynurenine 3-Monooxygenase/genetics , Kynurenine 3-Monooxygenase/metabolism , Reperfusion Injury/etiology , Reperfusion Injury/metabolism , Animals , Chromatography, Liquid , Epithelial Cells/metabolism , Kidney Diseases/pathology , Kidney Tubules/cytology , Kidney Tubules/metabolism , Kynurenine/metabolism , Metabolic Networks and Pathways , Metabolomics/methods , Mice , Mice, Knockout , Neutrophil Infiltration , Reperfusion Injury/pathology , Tandem Mass Spectrometry , Tryptophan/metabolism
12.
J Biol Chem ; 293(26): 10172-10185, 2018 06 29.
Article in English | MEDLINE | ID: mdl-29752407

ABSTRACT

The formin protein dishevelled-associated activator of morphogenesis 1 (DAAM1) polymerizes straight actin filaments and mediates migration of cancer cells. However, how DAAM1 governs cell haptotaxis in response to collagen remains unexplored in breast cancer cells. We hypothesized that DAAM1 mediates invadopodia extension and cell haptotaxis in response to type IV collagen in association with integrin receptors. Using Boyden chamber membranes coated with type IV collagen, we show here that type IV collagen activates both DAAM1 and Ras homolog family member A (RHOA) and promotes haptotaxis of MDA-MB-231 and MDA-MB-453 breast cancer cells, a process abolished by treatment with the integrin αvß3 inhibitor cyclo(-RGDfK). shRNA-mediated knockdown of DAAM1 or a dominant-negative DAAM1 mutation (N-DAAM1) significantly decreased collagen-induced RHOA activity and the assembly of stress fibers, invadopodia extension, and cell haptotaxis. Immunoprecipitation and pulldown assays revealed that integrin αvß3 is associated with, but only indirectly binds to, the C-terminal DAD domain of DAAM1 in mammalian cells. Blockade of RHOA activation with a specific inhibitor (CCG-1423) or via a dominant-negative RHOA mutation (RHOA-N19) suppressed collagen-induced invadopodia extension and haptotaxis of the MDA-MB-231 and MDA-MB-453 cells. Immunoblotting and immunofluorescence assays indicated high DAAM1 and RHOA expression in invadopodia, which was abolished by cyclo(-RGDfK) treatment or DAAM1 knockdown. These findings have uncovered an integrin αvß3/DAAM1/RHOA signaling pathway for type IV collagen-induced invadopodia extension and haptotaxis in breast cancer cells. Targeting this pathway may be a means for reducing invasiveness and metastasis of breast cancer.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Breast Neoplasms/pathology , Chemotaxis/drug effects , Collagen/pharmacology , Integrin alphaVbeta3/metabolism , Podosomes/drug effects , Podosomes/metabolism , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , Microfilament Proteins , Signal Transduction/drug effects , Stress Fibers/drug effects , Stress Fibers/metabolism , rho GTP-Binding Proteins , rhoA GTP-Binding Protein/metabolism
13.
Cancer Cell Int ; 17: 112, 2017.
Article in English | MEDLINE | ID: mdl-29213214

ABSTRACT

BACKGROUND: We have reported that the phosphatidylinositol-3 kinase (PI3K)/Akt/RhoA signaling pathway mediates Wnt5a-induced cell migration of osteosarcoma cells. However, the specific receptors responding to Wnt5a ligand remain poorly defined in osteosarcoma metastasis. METHODS: Wound healing assays were used to measure the migration rate of osteosarcoma cells transfected with shRNA or siRNA specific against ROR2 or indicated constructs. We evaluated the RhoA activation in osteosarcoma MG-63 and U2OS cells with RhoA activation assay. A panel of inhibitors of PI3K and Akt treated osteosarcoma cells and blocked kinase activity. Western blotting assays were employed to measure the expression and activation of Akt. Clonogenic assays were used to measure the cell proliferation of ROR2-knockdown or ROR2-overexpressed osteosarcoma cells. RESULTS: Wnt5a-induced osteosarcoma cell migration was largely abolished by shRNA or siRNA specific against ROR2. Overexpression of RhoA-CA (GFP-RhoA-V14) was able to rescue the Wnt5a-induced cell migration blocked by ROR2 knockdown. The Wnt5a-induced activation of RhoA was mostly blocked by ROR2 knockdown, and elevated by ROR2 overexpression, respectively. Furthermore, we found that Wnt5a-induced cell migration was significantly retarded by RhoA-siRNA transfection or pretreatment of HS-173 (PI3Kα inhibitor), MK-2206 (Akt inhibitor), A-674563 (Akt1 inhibitor), or CCT128930 (Akt2 inhibitor). The activation of Akt was upregulated or downregulated by transfected with ROR2-Flag or ROR2-siRNA, respectively. Lastly, Wnt5a/ROR2 signaling does not alter the cell proliferation of MG-63 osteosarcoma cells. CONCLUSIONS: Taken together, we demonstrate that ROR2 receptor responding to Wnt5a ligand activates PI3K/Akt/RhoA signaling and promotes the migration of osteosarcoma cells.

14.
Oncotarget ; 8(57): 96935-96944, 2017 Nov 14.
Article in English | MEDLINE | ID: mdl-29228583

ABSTRACT

BACKGROUND: Recently, nomograms have been used as models for risk prediction in malignant tumor because they can predict the outcome of interest for a certain individual based on many variables. This study aimed to establish an effective prognostic nomogram for osteosarcoma based on the clinicopathological factors and microRNA-203. RESULTS: The results showed that miR-203 expression was significantly lower in osteosarcoma tissues compared with the corresponding adjacent tissues (P < 0.001). Patients with low miR-203 expression had poor overall survival (OS) in osteosarcoma. The histological type, tumor size, AJCC stage and miR-203 expression were integrated in the nomogram. The nomogram showed significantly better prediction of OS than for patients with non-metastatic osteosarcoma. The ROC curve also showed higher specificity and sensitivity for predicting 3- and 5-year osteosarcoma patients' survival compared with AJCC stage. The decision curve analysis also indicated more potential of clinical application of the nomogram compared with AJCC staging system. Moreover, our findings were supported by the validation cohort. MATERIALS AND METHODS: We retrospectively investigated 301 patients with non-metastatic osteosarcoma. Data from primary cohort (n = 198) were used to develop multivariate nomograms. This nomogram was internally validated for discrimination and calibration with bootstrap samples and was externally validated with an independent patient cohort (n = 103). CONCLUSIONS: Our proposed nomogram showed more accurate prognostic prediction for patients with non-metastatic osteosarcoma.

15.
Neural Regen Res ; 12(2): 283-289, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28400812

ABSTRACT

We previously found that oxygen-glucose-serum deprivation/restoration (OGSD/R) induces apoptosis of spinal cord astrocytes, possibly via caspase-12 and the integrated stress response, which involves protein kinase R-like endoplasmic reticulum kinase (PERK), eukaryotic initiation factor 2-alpha (eIF2α) and activating transcription factor 4 (ATF4). We hypothesized that edaravone, a low molecular weight, lipophilic free radical scavenger, would reduce OGSD/R-induced apoptosis of spinal cord astrocytes. To test this, we established primary cultures of rat astrocytes, and exposed them to 8 hours/6 hours of OGSD/R with or without edaravone (0.1, 1, 10, 100 µM) treatment. We found that 100 µM of edaravone significantly suppressed astrocyte apoptosis and inhibited the release of reactive oxygen species. It also inhibited the activation of caspase-12 and caspase-3, and reduced the expression of homologous CCAAT/enhancer binding protein, phosphorylated (p)-PERK, p-eIF2α, and ATF4. These results point to a new use of an established drug in the prevention of OGSD/R-mediated spinal cord astrocyte apoptosis via the integrated stress response.

16.
J Pain Res ; 10: 375-382, 2017.
Article in English | MEDLINE | ID: mdl-28243141

ABSTRACT

Lumbar disc herniation (LDH) is an important cause of radiculopathy, but the underlying mechanisms are incompletely understood. Many studies suggested that local inflammation, rather than mechanical compression, results in radiculopathy induced by LDH. On the molecular and cellular level, nuclear factor-kappa B (NF-κB) and nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome have been implicated in the regulation of neuroinflammation formation and progression. In this study, the autologous nucleus pulposus (NP) was implanted in the left L5 dorsal root ganglion (DRG) to mimic LDH in rats. We investigated the expression of NF-κB and the components of NLRP3 inflammasome in the DRG neurons in rats. Western blotting and immunofluorescence for the related molecules, including NLRP3, apoptosis-associated speck-like protein containing caspase-1 activator domain (ASC), caspase-1, interleukin (IL)-1ß, IL-18, IκBα, p-IκBα, p65, p-p65, and calcitonin gene-related peptide (CGRP) were examined. In the NP-treated group, the activations of NLRP3, ASC, caspase-1, IL-1ß, IL-18, p-IκBα, and p-p65 in DRG neurons in rats were elevated at 1 day after surgery, and the peak occurred at 7 days. Treatment with Bay11-7082, an inhibitor of the actions of IKK-ß, was able to inhibit expression and activation of the molecules (NLRP3, ASC, caspase-1, IL-1ß, IL-18, p-IκBα, and p-p65) and relieve the pain in rats. Our study shows that NF-κB and NLRP3 inflammasome are involved in the maintenance of NP-induced pain, and that Bay11-7082 could alleviate mechanical allodynia and thermal hyperalgesia by inhibiting NF-κB and NLRP3 inflammasome activation.

17.
Cancer Cell Int ; 17: 27, 2017.
Article in English | MEDLINE | ID: mdl-28289332

ABSTRACT

BACKGROUND: We have reported that the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway mediated Wnt5a-induced osteosarcoma cell migration. However, the signaling pathways regulating Wnt5a/PI3K/Akt-mediated cell migration remains poorly defined in osteosarcoma cells. METHODS: We evaluated the activations of RhoA, Rac1 and Cdc42 in osteosarcoma MG-63 and U2OS cells with small G-protein activation assay. Boyden chamber assays were used to confirm the migration of cells transfected indicated constructs or siRNA specific against RhoA. A panel of inhibitors of PI3K and Akt treated osteosarcoma cells and blocked kinase activity. Western blotting and RhoA activation assay were employed to measure the effect of kinase inhibitors and activations of RhoA and Akt. RESULTS: We found that Wnt5a had a potent stimulatory effect on RhoA activation, but not on Rac1 and Cdc42 activations. Wnt5a-induced cell migration was largely abolished by siRNA specific against RhoA. DN-RhoA (GFP-RhoA-N19) was also capable of retarding Wnt5a-induced cell migration, but the overexpression of CA-RhoA (GFP-RhoA-V14) was not able to accelerate cell migration. The Wnt5a-induced activation of RhoA was mostly blocked by pretreatment of LY294002 (PI3K inhibitor) and MK-2206 (Akt inhibitor). Furthermore, we found that the Wnt5a-induced activation of RhoA was mostly blocked by pretreatment of HS-173 (PI3Kα inhibitor). Lastly, the phosphorylation of Akt (p-Ser473) was not altered by transfection with siRNA specific against RhoA or DN-RhoA (GFP-RhoA-N19). CONCLUSIONS: Taken together, we demonstrate that RhoA acts as the downstream of PI3K/Akt signaling (specific PI3Kα, Akt1 and Akt2 isoforms) and mediated Wnt5a-induced the migration of osteosarcoma cells.

18.
J Immunol ; 197(5): 1968-78, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27481847

ABSTRACT

Activation of TGF-ß by dendritic cells (DCs) expressing αvß8 integrin is essential for the generation of intestinal regulatory T cells (Tregs) that in turn promote tolerance to intestinal Ags. We have recently shown that αvß8 integrin is preferentially expressed by CD103(+) DCs and confers their ability to activate TGF-ß and generate Tregs. However, how these DCs become specialized for this vital function is unknown. In this study, we show that ß8 expression is controlled by a combination of factors that include DC lineage and signals derived from the tissue microenvironment and microbiota. Specifically, our data demonstrate that TGF-ß itself, along with retinoic acid and TLR signaling, drives expression of αvß8 in DCs. However, these signals only result in high levels of ß8 expression in cells of the cDC1 lineage, CD8α(+), or CD103(+)CD11b(-) DCs, and this is associated with epigenetic changes in the Itgb8 locus. Together, these data provide a key illustrative example of how microenvironmental factors and cell lineage drive the generation of regulatory αvß8-expressing DCs specialized for activation of TGF-ß to facilitate Treg generation.


Subject(s)
Cell Lineage , Cellular Microenvironment , Dendritic Cells/immunology , Integrin beta Chains/metabolism , Intestines/cytology , Transforming Growth Factor beta/metabolism , Animals , Antigens, CD/genetics , Antigens, CD/immunology , Cell Differentiation , Dendritic Cells/physiology , Integrin alpha Chains/genetics , Integrin alpha Chains/immunology , Integrin beta Chains/genetics , Integrin beta Chains/immunology , Intestines/immunology , Mice , T-Lymphocytes, Regulatory/physiology , Toll-Like Receptors/immunology , Toll-Like Receptors/metabolism , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/immunology , Tretinoin/metabolism
19.
Cancer Cell Int ; 14(1): 15, 2014 Feb 14.
Article in English | MEDLINE | ID: mdl-24524196

ABSTRACT

Wnt5a is classified as a non-transforming Wnt family member and plays complicated roles in oncogenesis and cancer metastasis. However, Wnt5a signaling in osteosarcoma progression remains poorly defined. In this study, we found that Wnt5a stimulated the migration of human osteosarcoma cells (MG-63), with the maximal effect at 100 ng/ml, via enhancing phosphorylation of phosphatidylinositol-3 kinase (PI3K)/Akt. PI3K and Akt showed visible signs of basal phosphorylation and elevated phosphorylation at 15 min after stimulation with Wnt5a. Pharmaceutical inhibition of PI3K with LY294002 significantly blocked the Wnt5a-induced activation of Akt (p-Ser473) and decreased Wnt5a-induced cell migration. Akt siRNA remarkably inhibited Wnt5a-induced cell migration. Additionally, Wnt5a does not alter the total expression and phosphorylation of ß-catenin in MG-63 cells. Taken together, we demonstrated for the first time that Wnt5a promoted osteosarcoma cell migration via the PI3K/Akt signaling pathway. These findings could provide a rationale for designing new therapy targeting osteosarcoma metastasis.

20.
Ying Yong Sheng Tai Xue Bao ; 25(10): 3017-22, 2014 Oct.
Article in Chinese | MEDLINE | ID: mdl-25796914

ABSTRACT

The sex pheromone gland extracts collected from calling females of Apamea apameoides (Lepidoptera: Noctuidae) were analyzed with GC-MS, the electrophysiological and behavioral responses of the male adults to serial dilutions of sex pheromone components and their synthetic blends were investigated with Y-tube olfactometer in laboratory and in bamboo forest field. The results indicated that (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol were the functional components in the sex pheromone gland extracts. Electroantennogram (EAG) recordings showed that sex pheromone gland extracts, (Z)-11-hexadecenyl acetate, (Z)-11-hexadecen-1-ol and the mixture of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol all could elicit strong EAG responses, and the average EAG values increased with the increasing concentration of the sex pheromone. The blends of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol at the ratio of 57:43 elicited a higher EAG value than each singular component did. The results of behavioral assay by Y-tube olfactometer accorded with those of EAG responses on the whole, and the mixture of (Z)-11-hexadecenyl acetate and (Z)-11-hexadecen-1-ol at the ratio of 57:43 was more attractive than each component alone. In field tests with silicone rubber as pheromone dispensers (concentration = 10(4) ng · uL(-1)), the average number of male adults captured per trap by the mixture was (48.5 ± 6.7).


Subject(s)
Electrophysiological Phenomena , Moths/physiology , Sex Attractants/chemistry , Sexual Behavior, Animal , Acetates/chemistry , Animals , Female , Gas Chromatography-Mass Spectrometry , Male
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