scholarly journals NF-κB Signaling Pathway in Controlling Intervertebral Disk Cell Response to Inflammatory and Mechanical Stressors

2016 ◽  
Vol 96 (5) ◽  
pp. 704-711 ◽  
Author(s):  
Robert Tisherman ◽  
Paulo Coelho ◽  
David Phillibert ◽  
Dong Wang ◽  
Qing Dong ◽  
...  
Keyword(s):  
Gene Expression ◽  
Signaling Pathway ◽  
Mechanical Stimulation ◽  
Cell Response ◽  
Annulus Fibrosus ◽  
Nuclear Translocation ◽  
Intervertebral Disk ◽  
Immunofluorescent Staining ◽  
Matrix Synthesis

Background Intervertebral disk degeneration (IDD) has a greater than 90% lifetime incidence and is one of the leading causes of chronic back pain in the United States. Despite the high societal cost of IDD, there is limited understanding of the biological effects of mechanical overloading on further degeneration. The transcription factor NF-κB (nuclear factor κB) has been implicated as a key mediator of disk cell response to inflammatory and mechanical stresses and represents a potential control point. Objective The study objective was to measure the effect of NF-κB signaling pathway inhibition on annulus fibrosus (AF) cell matrix synthesis and gene expression under conditions of combined inflammatory and mechanical stimulation. Methods Annulus fibrosus cells were harvested from rabbit intervertebral disks and grown in vitro on flexible plates. The cells were exposed to inflammatory and mechanical stimulation for 24 hours with and without NF-κB inhibition. Nuclear translocation of NF-κB was measured via immunofluorescent staining. Intervertebral disk cell homeostasis was assessed via inflammatory, anabolic, and catabolic gene expression and via matrix synthetic ability. Results NF-κB nuclear translocation in response to interleukin-1 beta (IL-1β) was reversed with exposure to NF-κB inhibition. NF-κB inhibition decreased matrix metalloproteinase-3, inducible nitric oxide synthase, and cyclooxygenase-2 gene expression and prostaglandin E2 production response to combined inflammatory and mechanical stimulation. Proteoglycan and collagen synthesis were decreased by combined stimulation, but this effect was not reversed by NF-κB inhibition. Limitations In vitro modeling of conditions within the disk may not fully reflect the response that AF cells have in native matrix. Conclusions NF-κB signaling mediates catabolic and inflammatory responses to inflammatory and mechanical stimulation but does not mediate the decrease in matrix synthesis under combined harmful stimulation. Identification of key control points in the cellular responses to inflammatory and mechanical stimuli will facilitate rational design of exercise-based therapies and facilitate synergistic treatments of novel biochemical treatments with rehabilitation regimens.

scholarly journals Pentamethylquercetin Attenuates Cardiac Remodeling via Activation of the Sestrins/Keap1/Nrf2 Pathway in MSG-Induced Obese Mice

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Jingxia Du ◽  
Wei He ◽  
Cai Zhang ◽  
Jianzhao Wu ◽  
Zhi Li ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Cardiac Remodeling ◽  
Metabolic Disorders ◽  
Cardiac Fibrosis ◽  
Nuclear Translocation ◽  
Monosodium Glutamate ◽  
Immunofluorescent Staining ◽  
Obese Mice ◽  
Nrf2 Signaling Pathway ◽  
Obesity Cardiomyopathy

Objective. Obesity causes a variety of metabolic alterations that may contribute to abnormalities of the cardiac structure and function (obesity cardiomyopathy). In previous works, we have shown that pentamethylquercetin (PMQ) significantly improved metabolic disorders in obese mice and it inhibited pressure overload-induced cardiac remodeling in mice. However, its potential benefit in obesity cardiomyopathy remains unclear. The aim of this study was to investigate the effects of PMQ on cardiac remodeling in obese mice. Methods. We generated a monosodium glutamate-induced obese (MSG-IO) model in mice, which were treated with PMQ (5, 10, and 20 mg/kg) for 16 weeks consecutively. We examined the metabolic parameters and observed cardiac remodeling by performing cardiac echocardiography and Masson’s staining. The expression levels of molecules associated with the endogenous antioxidant system, including the sestrins/kelch-like ECH-associated protein 1 (Keap1)/Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) signaling pathway, were analyzed by western blotting and immunofluorescent staining. Results. We found that PMQ treatment significantly ameliorated obesity phenotypes and improved metabolic disorders in MSG-IO mice. PMQ decreased the heart wall thickness and attenuated cardiac fibrosis. Further study revealed that the protective effects of PMQ might be mediated by promoting Keap1 degradation and augmenting sestrins expression and Nrf2 nuclear translocation. Conclusion. Our findings indicated that PMQ ameliorated cardiac remodeling in obese mice by targeting the sestrins/Keap1/Nrf2 signaling pathway.

scholarly journals Bone Marrow-Derived CD44+Cells Migrate to Tissue-Engineered Constructs via SDF-1/CXCR4-JNK Pathway and Aid Bone Repair

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Yanzhu Lu ◽  
Junchao Xing ◽  
Xiaolong Yin ◽  
Xiaobo Zhu ◽  
Aijun Yang ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Signaling Pathway ◽  
Bone Repair ◽  
Bone Marrow Cells ◽  
Complex Model ◽  
Host Cells ◽  
Immunofluorescent Staining ◽  
Jnk Pathway

Background and Aims.Host-derived cells play crucial roles in the regeneration process of tissue-engineered constructs (TECs) during the treatment of large segmental bone defects (LSBDs). However, their identity, source, and cell recruitment mechanisms remain elusive.Methods.A complex model was created using mice by combining methods of GFP+bone marrow transplantation (GFP-BMT), parabiosis (GFP+-BMT and wild-type mice), and femoral LSBD, followed by implantation of TECs or DBM scaffolds. Postoperatively, the migration of host BM cells was detected by animal imaging and immunofluorescent staining. Bone repair was evaluated by micro-CT. Signaling pathway repressors including AMD3100 and SP600125 associated with the migration of BM CD44+cells were further investigated.In vitro, transwell migration and western-blotting assays were performed to verify the related signaling pathway.In vivo, the importance of the SDF-1/CXCR4-JNK pathway was validated by ELISA, fluorescence-activated cell sorting (FACS), immunofluorescent staining, and RT-PCR.Results.First, we found that host cells recruited to facilitate TEC-mediated bone repair were derived from bone marrow and most of them express CD44, indicating the significance of CD44 in the migration of bone marrow cells towards donor MSCs. Then, the predominant roles of SDF-1/CXCR4 and downstream JNK in the migration of BM CD44+cells towards TECs were demonstrated.Conclusion.Together, we demonstrated that during bone repair promoted by TECs, BM-derived CD44+cells were essential and their migration towards TECs could be regulated by the SDF-1/CXCR4-JNK signaling pathway.

Integrin signaling's potential for mediating gene expression in hypertrophying skeletal muscle

2000 ◽  
Vol 88 (1) ◽  
pp. 337-343 ◽  
Author(s):  
James A. Carson ◽  
Lei Wei
Keyword(s):  
Gene Expression ◽  
Skeletal Muscle ◽  
Signaling Pathway ◽  
Mechanical Load ◽  
Integrin Signaling ◽  
Mechanical Forces ◽  
Growth Factor Signaling ◽  
Muscle Gene

Overloaded skeletal muscle undergoes dramatic shifts in gene expression, which alter both the phenotype and mass. Molecular biology techniques employing both in vivo and in vitro hypertrophy models have demonstrated that mechanical forces can alter skeletal muscle gene regulation. This review's purpose is to support integrin-mediated signaling as a candidate for mechanical load-induced hypertrophy. Research quantifying components of the integrin-signaling pathway in overloaded skeletal muscle have been integrated with knowledge regarding integrins role during development and cardiac hypertrophy, with the hope of demonstrating the pathway's importance. The role of integrin signaling as an integrator of mechanical forces and growth factor signaling during hypertrophy is discussed. Specific components of integrin signaling, including focal adhesion kinase and low-molecular-weight GTPase Rho are mentioned as downstream targets of this signaling pathway. There is a need for additional mechanistic studies capable of providing a stronger linkage between integrin-mediated signaling and skeletal muscle hypertrophy; however, there appears to be abundant justification for this type of research.

Enhancing Cytotoxicity of Autologous T Cells in AML By Blockade of CTLA-4 and PD-1

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4057-4057 ◽  
Author(s):  
Kirsten Marie Boughan ◽  
Xiaohua Chen ◽  
Paul Szabolcs
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Response ◽  
Conflicts Of Interest ◽  
Expression Profiles ◽  
T Cell Response ◽  
Inhibitory Receptors

Abstract Background: AML remains a disease diagnosed in the aging population with chemotherapy followed by bone marrow transplant in some cases being the standard of care. Although response rates remain around 50-60%, treatment related mortality and disease relapse remain high. Adoptive immunotherapy, especially those targeting T cell co-inhibitory receptors, has proven successful in solid malignancies however, AML remains less explored. Our laboratory has previously demonstrated the feasibility to generate autologous AML reactive T cells in vitro (Mehta/Szabolcs; Immunotherapy 2016). It was noted that "resistant" AML blasts over expressed a number of genes associated with immunosuppressive characteristics. Over expression of these genes may induce T cell functional exhaustion. Therefore, we hypothesized that blocking PD-1 and/or CTLA-4 during co-culture with IFNg activated AML blasts, may enhance T cell activation and cytotoxicity. To test this hypothesis, we tested CTL responses against AML blasts and IFNg ELISpot formation after blocking with PD-1, CTLA-4 or both receptors, and compared the response in untreated T cells. Gene expression profiles of co-stimulatory/co-inhibitory receptors were also monitored to test for correlation. Methods: We evaluated 12 patients with newly diagnosed AML under an IRB approved protocol with written informed consent of patients. Mononuclear cell preparation was generated from fresh marrow samples or drawn from a biorepository of previously cryopreserved leukophereses. T cells were then purified using immunomagnetic CD3/CD28 beads (Life technologies) and cultivated in media with IL-2 and IL-7 for 2 weeks. AML blasts were cultured over a supporting layer of mesenchymal stromal cells (MSCs) derived from healthy BM donors for 1 week and then cryopreserved. T cells were then co-cultured with restored and irradiated autologous AML cells at an effector: target (E: T) ratio of 5:1 to 40:1. AML and T cells were co-cultured in the presence of Ipilimumab (anti-CTLA-4), or Nivolumab (anti-PD-1), or a combination of both drugs. T cells and AML were re stimulated in X-vivo 15 with IL-12, IL-15 and IL-2 weekly x 3weeks. T cell response to AML was quantitated by IFNg ELISpot assay and Europium TDA (EuTDA) CTL assays independently. Co-stimulatory/co-inhibitory expression on T cells was examined with RT-q PCR assay. Paired-sample student t test was used for statistical analysis with p<0.05. Results and Discussion: Out of 12 samples, 10 (83%) yielded viable AML cells available for cytotoxicity assay. One third (33%) of co-cultures exhibited a positive T cell response in CTL assays ("killers"). There was no difference in CTL activity by blockade of either PD-1 or CTL-4 (Fig 1). IFN-ɣ spot formation in ELISpot was observed in 4/10 samples (40%) with statistical significance noted in cells blocked with PD-1 as compared to all other blockade types (Fig 2). The results indicated that in vitro priming with autologous AML blasts or together with blocking PD-1 can enhance T cell response in 33-40%. By gene expression analysis, the ratio of co-stimulatory to co-inhibitory genes was calculated. In PD-1 blocked cells, the ratio of activation/inhibition was not impacted in T cells from "killers" (0.9; p=0.1), however, T cells from "non-killer cells" had a diminished ratio due to higher expression of co-inhibitory molecules (0.4; p=0.04) (Fig 3). This trend was also present in CTLA-4 blocked cells (0.85; p=0.4 in killers vs 0.54; p=0.03 in non-killers) (data not shown). Interestingly, dual blockage failed to influence gene expression ratio, data not shown. Conclusion: The above studies demonstrate that cytotoxicity can be achieved in T cells when primed against autologous AML. PD-1 blockade can enhance IFNg production and cytotoxic responses, but CTLA-4 and dual blockade failed to enhance T cell function. The upregulation of an inhibitory pattern of genes in T cells that did not express cytotoxicity (non-killers) could allude to an "inhibitory phenotype" that may be resistant to immunotherapy drug blockade and requires further study. Disclosures No relevant conflicts of interest to declare.

Icariin Promotes Extracellular Matrix Synthesis and Gene Expression of Chondrocytes In Vitro

2012 ◽  
Vol 26 (9) ◽  
pp. 1385-1392 ◽  
Author(s):  
Lei Zhang ◽  
Xuan Zhang ◽  
Kui-Feng Li ◽  
Dong-Xiao Li ◽  
Yu-Mei Xiao ◽  
...  
Keyword(s):  
Gene Expression ◽  
Extracellular Matrix ◽  
Matrix Synthesis

scholarly journals Glaucocalyxin A Attenuates Allergic Responses by Inhibiting Mast Cell Degranulation through p38MAPK/NrF2/HO-1 and HMGB1/TLR4/NF-κB Signaling Pathways

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Yihua Piao ◽  
Jingzhi Jiang ◽  
Zhiguang Wang ◽  
Chongyang Wang ◽  
Shan Jin ◽  
...  
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Signaling Pathway ◽  
Nuclear Translocation ◽  
Calcium Influx ◽  
Mast Cell Degranulation ◽  
Therapeutic Drug ◽  
High Mobility Group Protein

Glaucocalyxin A (GLA) has various pharmacological effects like antioxidation, immune regulation, and antiatherosclerosis. Here, in this study, the effect and mechanism of GLA on mast cell degranulation were studied. The results of the anti-DNP IgE-mediated passive cutaneous anaphylaxis (PCA) showed that GLA dramatically inhibited PCA in vivo, as evidenced by reduced Evans blue extravasation and decreased ear thickness. In addition, GLA significantly reduced the release of histamine and β-hexosaminidase, calcium influx, cytokine (IL-4, TNF-α, IL-1β, IL-13, and IL-8) production in the RBL-2H3 (rat basophilic leukemia cells), and RPMCs (peritoneal mast cells) in vitro. Moreover, we further investigated the regulatory mechanism of GLA on antigen-induced mast cells by Western blot, which showed that GLA inhibited FcεRI-mediated signal transduction and invalidated the phosphorylation of Syk, Fyn, Lyn, Gab2, and PLC-γ1. In addition, GLA inhibited the recombinant mouse high mobility group protein B1- (HMGB1-) induced mast cell degranulation through limiting nuclear translocation of NF-κBp65. Treatment of mast cells with siRNA-HMGB1 significantly inhibited HMGB1 levels, as well as MyD88 and TLR4, decreased intracellular calcium levels, and suppressed the release of β-hexosaminidase. Meanwhile, GLA increased NrF2 and HO-1 levels by activating p38MAPK phosphorylation. Consequently, these data suggest that GLA regulates the NrF2/HO-1 signaling pathway through p38MAPK phosphorylation and inhibits HMGB1/TLR4/NF-κB signaling pathway to reduce mast cell degranulation and allergic inflammation. Our findings could be used as a promising therapeutic drug against allergic inflammatory disease.

Transcriptional gene expression profile in hepatocarcinoma cells induced by acetylsalicylic acid (ASA) in hepatitis C virus (HCV)-subgenomic replicon system.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e22016-e22016
Author(s):  
Clara Patricia Rios Ibarra ◽  
Barbara Verduzco Garza ◽  
Rocio Ortiz Lopez ◽  
Yohann Grondin ◽  
Sonia Lozano Sepulveda ◽  
...  
Keyword(s):  
Gene Expression ◽  
Signaling Pathway ◽  
Expression Profile ◽  
Molecular Mechanisms ◽  
Antiviral Effect ◽  
Subgenomic Replicon ◽  
Expression Of Genes ◽  
Antioxidant Agents ◽  
Hepatocarcinoma Cells

e22016 Background: It has been demonstrated that ASA treatment could down-regulate in vitro HCV expression in hepatocarcinoma cells (~50%, p 0.05). However, the signaling pathway induced during ASA antiviral effect has not been elucidated. We analyzed the transcriptional expression profile of Huh-7-HCV-subgenomic replicon cells in presence or absence of ASA in order to identify the signaling pathway and the molecular mechanisms involved in the antiviral effect induced by ASA on HCV expression. Methods: Huh-7-HCV-replicon cells (hepatocarcinoma) were exposed to 4 mM ASA from 24 to 72 hours. Total RNA was isolated, quantified and validated by capillary electrophoresis. After that, we performed a retrotranscription in vitro. Synthesized transcripts were marked with biotin, purified, fragmentized and hybridized in HG-U133 Plus 2 Gene Expression. Hybridization signals were captured with Gen Chip 3000 7G Scanner and analyzed by Expression Console and Dchit Software. Results: After normalization, we obtained hierarchical maps with differentially-expressed genes. Among genetic targets over-expressed, the following stood out CCAAT-enhancer-binding proteins (C/EBP), interleukine-8 (IL-8), cytochrome P450 (CyP450) and methallothioneins (MT) genes were found. Among down-regulated genes we identified ribonucleotide reductase (RR) and superoxide dismutase (SOD) genes. Some of these genes have been previously associated with oxidative stress regulation. All results were validated by real time PCR. Conclusions: We observed that ASA modulates the expression of genes associated with antioxidant role as SOD and methallothioneins. Antioxidant agents can inhibit virus proliferation. HCV decreased antioxidant defense, which promotes the development of hepatic complications caused by HCV infection, including liver cancer. Therefore, ASA could be inducing an antioxidant environment regulating HCV replication. This study provides a tool for identifying novel host factors in hepatocarcinoma cells involved in the antiviral effect regulated by ASA against HCV and improves our understanding of the regulatory mechanism of HCV replication.

PDGFR-Mediated Cytomegalovirus Infection of Megakaryocytes Induces Thrombocytopenia Via Demethylation of AML1 and IEX-1 in the TPO/c-Mpl Signaling Pathway Following Allo-HSCT

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3937-3937
Author(s):  
Xiao-Hui Zhang ◽  
Feng Fei-er ◽  
Qian-ming Wang ◽  
Xiao-lu Zhu ◽  
Lan-ping Xu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Bone Marrow ◽  
Signaling Pathway ◽  
Cell Apoptosis ◽  
Hcmv Infection ◽  
Treated Group ◽  
In Vitro Studies ◽  
Significant Difference

Abstract Introduction: Human cytomegalovirus (HCMV) infection is a common complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), which is associated with high morbidity and mortality. Thrombocytopenia is one of the major hematological complications of HCMV infection. Possible causes include direct HCMV injury to hematopoietic progenitor cells and the microenvironment, as well as HCMV-related immune thrombocytopenia. Previous in vitro studies demonstrate that HCMV could directly infect megakaryocytes(MKs) and their progenitors, resulting in decreased CFU-MK and increased apoptosis, but the underlying mechanisms remain uncertain. It remains unknown whether HCMV can directly target MKs in vivo, how MK function changes after infection, why HCMV selectively infects certain patients and what inhibits MK maturation and results in apoptosis. It has been reported that patients with HCMV-related thrombocytopenia showed poor response to rhTPO, implying blockage of the TPO/c-Mpl signaling pathway. Our previous research indicated that PDGFR+CXCR4lowCCR5lowMKs are correlated with HCMV infection.We hypothesized that PDGFR+CXCR4lowCCR5lowMKs are more susceptible to HCMV infection. HCMV could directly target MKs both in vitro and in vivo, resulting in increased apoptosis and decreased MK ploidy. HCMV infection could possibly disturb the downstream TPO/c-Mpl signaling pathway, thereby inhibiting MK differentiation and maturation. Methods: We collected bone marrow from HCMV DNAemia patients post allo-HSCT for in vivo study. Transmission electron microscopy(TEM) was used to detect HCMV particles inside MKs. MKs were identified as CD41+vWF+cells by flow cytometry(FCM). To analyze the susceptibility of MKs to HCMV, expression levels of PDGFR, αvβ3, TLR2, CCR5 and CXCR4 in different groups were tested. Cell apoptosis was measured by Annexin V. MK ploidy was determined by FCM for propidium iodide (PI) staining. We also measured c-Mpl expression in MKs.In vitro study, we used plasma from HCMV-infected patients post allo-HSCT to infect MKs cultured from bone marrow CD34+ cells. We validated cell susceptibility with the same markers used in vivo. Next, inhibitors of the positive markers were co-cultured with MKs. We analyzed pp65 expression in the inhibitor-treated group and control group to explore potential prevention of HCMV infection. We investigated AML1 and IEX-1 in the downstream TPO/c-Mpl signaling pathway by PCR and Western Blot. We used bisulfite sequencing PCR (BSP) to study the methylation status in different gene expression profiles of AML1 and IEX-1. 5-ara-dC is a type of DNA methylation inhibitor. After incubation with MKs, we analyzed changes in gene expression and MKs function. Results: Using TEM, we managed to find HCMV particles in MKs from HCMV-infected patient bone marrow samples. The proportion of apoptosis markedly increased compared with HCMV-negative MKs, whereas the mean ploidy slightly decreased. C-Mpl expression showed no significant difference between the two groups. Pp65 positive cells showed elevated expression in PDGFR and reduced expression in CXCR4 and CCR5. In vitro studies revealed similar results. After treating with the PDGFR inhibitor IMC-3G3, the pp65 positive cell population was slightly decreased, but the Gleevec-treated group showed no difference. We found a decrease in both IEX-1 and AML1 on both the molecular and protein levels. Both gene promoters were hypermethylated in the HCMV-infected group. After demethylation with 5-ara-dC, IEX-1 and AML1expression levels were both up-regulated, and cell apoptosis was reduced. Conclusion: (1)HCMV inhibited megakaryocytic differentiation and maturation and reduced MKs polyploidy both in vivo and in vitro. (2)MKs positive for PDGFR and low in CXCR4 and CCR5 were more susceptible to HCMV infection. The PDGFR inhibitor IMC-3G3 protected MKs from HCMV infection. (3)The mechanism of HCMV-associated thrombocytopenia may be a disturbance of the TPO/c-Mpl signaling pathway in MKs through hypermethylation of the AML1 and IEX-1 promoters. Demethylation with 5-ara-dC could reverse cell apoptosis. Therefore, we illustrated the possible mechanism of HCMV-induced thrombocytopenia, highlighting new insights for future potential therapeutic approaches. Disclosures No relevant conflicts of interest to declare.

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