scholarly journals Corticotropin-Releasing Hormone Augments Proinflammatory Cytokine Production from Macrophages In Vitro and in Lipopolysaccharide-Induced Endotoxin Shock in Mice

2002 ◽  
Vol 70 (11) ◽  
pp. 6068-6074 ◽  
Author(s):  
Sofia Agelaki ◽  
Christos Tsatsanis ◽  
Achille Gravanis ◽  
Andrew N. Margioris
Keyword(s):  
Proinflammatory Cytokine ◽  
Cytokine Production ◽  
Endotoxin Shock ◽  
Proinflammatory Cytokine Production ◽  
Corticotropin Releasing Hormone ◽  
Necrosis Factor Alpha ◽  
Releasing Hormone ◽  
Tnf Α

ABSTRACT Corticotropin-releasing hormone (CRH) exerts an anti-inflammatory effect indirectly, via cortisole production, and a proinflammatory effect directly on immune cells. The aim of the present work was to examine the effect of CRH on macrophage-derived cytokines both in vitro and in vivo. For the in vitro experiments we used two types of macrophages: (i) the RAW264.7 monocyte/macrophage cell line and (ii) thioglycolate-elicited peritoneal macrophages from BALB/c mice. We have found that CRH enhanced lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 production. For the in vivo experiments we have used the LPS-induced endotoxin shock model in BALB/c mice, an established model for systemic inflammation in which macrophages are the major source of the proinflammatory cytokines responsible for the development of the shock. Administration of antalarmin, a synthetic CRH receptor 1 (CRHR1) antagonist, prior to LPS prolonged survival in a statistically significant manner. The effect was more evident at the early stages of endotoxin shock. CRHR1 blockade suppressed LPS-induced elevation of the macrophage-derived cytokines TNF-α, IL-1β, and IL-6, confirming the role of CRH signals in cytokine expression. In conclusion, our data suggest that CRH signals play an early and crucial role in augmenting LPS-induced proinflammatory cytokine production by macrophages. Our data suggest that the diffuse neuroendocrine system via CRH directly affects the immune system at the level of macrophage activation and cytokine production.

Modulatory effects of ozone on THP-1 cells in response to SP-A stimulation

2005 ◽  
Vol 288 (2) ◽  
pp. L317-L325 ◽  
Author(s):  
Branislava Janic ◽  
Todd M. Umstead ◽  
David S. Phelps ◽  
Joanna Floros
Keyword(s):  
Immune Cells ◽  
Cytokine Production ◽  
Cell Damage ◽  
Surfactant Protein ◽  
Proinflammatory Cytokine Production ◽  
Tnf Α ◽  
In Vitro Systems ◽  
Alveolar Proteinosis

Ozone (O3), a major component of air pollution and a strong oxidizing agent, can lead to lung injury associated with edema, inflammation, and epithelial cell damage. The effects of O3on pulmonary immune cells have been studied in various in vivo and in vitro systems. We have shown previously that O3exposure of surfactant protein (SP)-A decreases its ability to modulate proinflammatory cytokine production by cells of monocyte/macrophage lineage (THP-1 cells). In this report, we exposed THP-1 cells and/or native SP-A obtained from bronchoalveolar lavage of patients with alveolar proteinosis to O3and studied cytokine production and NF-κB signaling. The results showed 1) exposure of THP-1 cells to O3significantly decreased their ability to express TNF-α in response to SP-A; TNF-α production, under these conditions, was still significantly higher than basal (unstimulated) levels in filtered air-exposed THP-1 cells; 2) exposure of both THP-1 cells and SP-A to O3did not result in any significant differences in TNF-α expression compared with basal levels; 3) O3exposure of SP-A resulted in a decreased ability of SP-A to activate the NF-κB pathway, as assessed by the lack of significant increase and decrease of the nuclear p65 subunit of NF-κB and cytoplasmic IκBα, respectively; and 4) O3exposure of THP-1 cells resulted in a decrease in SP-A-mediated THP-1 cell responsiveness, which did not seem to be mediated via the classic NF-κB pathway. These findings indicate that O3exposure may mediate its effect on macrophage function both directly and indirectly (via SP-A oxidation) and by involving different mechanisms.

scholarly journals Micrococcus luteus Teichuronic Acids Activate Human and Murine Monocytic Cells in a CD14- and Toll-Like Receptor 4-Dependent Manner

2001 ◽  
Vol 69 (4) ◽  
pp. 2025-2030 ◽  
Author(s):  
Shuhua Yang ◽  
Shunji Sugawara ◽  
Toshihiko Monodane ◽  
Masahiro Nishijima ◽  
Yoshiyuki Adachi ◽  
...  
Keyword(s):  
Lipid A ◽  
Micrococcus Luteus ◽  
Dependent Manner ◽  
Toll Like Receptor ◽  
Toll Like Receptor 4 ◽  
Necrosis Factor Alpha ◽  
Monocytic Cells ◽  
Tnf Α

ABSTRACT Teichuronic acid (TUA), a component of the cell walls of the gram-positive organism Micrococcus luteus (formerlyMicrococcus lysodeikticus), induced inflammatory cytokines in C3H/HeN mice but not in lipopolysaccharide (LPS)-resistant C3H/HeJ mice that have a defect in the Toll-like receptor 4 (TLR4) gene, both in vivo and in vitro, similarly to LPS (T. Monodane, Y. Kawabata, S. Yang, S. Hase, and H. Takada, J. Med. Microbiol. 50:4–12, 2001). In this study, we found that purified TUA (p-TUA) induced tumor necrosis factor alpha (TNF-α) in murine monocytic J774.1 cells but not in mutant LR-9 cells expressing membrane CD14 at a lower level than the parent J774.1 cells. The TNF-α-inducing activity of p-TUA in J774.1 cells was completely inhibited by anti-mouse CD14 monoclonal antibody (MAb). p-TUA also induced interleukin-8 (IL-8) in human monocytic THP-1 cells differentiated to macrophage-like cells expressing CD14. Anti-human CD14 MAb, anti-human TLR4 MAb, and synthetic lipid A precursor IVA, an LPS antagonist, almost completely inhibited the IL-8-inducing ability of p-TUA, as well as LPS, in the differentiated THP-1 cells. Reduced p-TUA did not exhibit any activities in J774.1 or THP-1 cells. These findings strongly suggested that M. luteus TUA activates murine and human monocytic cells in a CD14- and TLR4-dependent manner, similar to LPS.

scholarly journals Metabolic Profiling of Buddleia indica Leaves using LC/MS and Evidence of their Antioxidant and Hepatoprotective Activity Using Different In Vitro and In Vivo Experimental Models

Antioxidants ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 412
Author(s):  
Fadia S. Youssef ◽  
Mohamed L. Ashour ◽  
Hesham A. El-Beshbishy ◽  
Abdel Nasser B. Singab ◽  
Michael Wink
Keyword(s):  
Antioxidant Properties ◽  
Lipid Peroxide ◽  
Hepatoprotective Activity ◽  
Experimental Models ◽  
Ionization Mass ◽  
Necrosis Factor Alpha ◽  
Stress Markers ◽  
Tnf Α

LC-ESI-MS (Liquid Chromatography coupled with Electrospray Ionization Mass Spectrometry profiling of a methanol extract from Buddleia indica (BIM) leaves revealed 12 main peaks in which verbascoside and buddlenoid B represent the major compounds. The antioxidant and hepatoprotective activities of BIM were investigated using different in vitro and in vivo experimental models. BIM exhibited substantial in vitro antioxidant properties in DPPH· and HepG2 assays. Regarding CCl4 (carbon tetrachloride) induced hepatotoxicity in a rat model, oxidative stress markers became significantly ameliorated after oral administration of BIM. Lipid peroxide levels showed a 51.85% decline relative to CCl4-treated rats. Super oxide dismutase (SOD), total antioxidant status (TAS), and catalase (CAT) revealed a marked increase by 132.48%, 187.18%, and 114.94% relative to the CCl4 group. In a tamoxifen-induced hepatotoxicity model, BIM showed a considerable alleviation in liver stress markers manifested by a 46.06% and 40% decline in ALT (Alanine Transaminase) and AST (Aspartate Transaminase) respectively. Thiobarbituric acid reactive substances (TBARS) were reduced by 28.57% and the tumor necrosis factor alpha (TNF-α) level by 50%. A virtual screening of major secondary metabolites of BIM to TNF-alpha employing the C-docker protocol showed that gmelinoside H caused the most potent TNF- α inhibition as indicated from their high fitting scores. Thus, BIM exhibited a potent hepatoprotective activity owing to its richness in antioxidant metabolites.

scholarly journals Human Cytomegalovirus MicroRNAs miR-US5-1 and miR-UL112-3p Block Proinflammatory Cytokine Production in Response to NF-κB-Activating Factors through Direct Downregulation of IKKα and IKKβ

mBio ◽  
2017 ◽  
Vol 8 (2) ◽  
Author(s):  
Meaghan H. Hancock ◽  
Lauren M. Hook ◽  
Jennifer Mitchell ◽  
Jay A. Nelson
Keyword(s):  
Human Cytomegalovirus ◽  
Proinflammatory Cytokines ◽  
Proinflammatory Cytokine ◽  
Hcmv Infection ◽  
Cytokine Production ◽  
Lytic Infection ◽  
Wild Type Virus ◽  
Proinflammatory Cytokine Production ◽  
Iκb Kinase ◽  
Tnf Α

ABSTRACTEmerging evidence indicates that human cytomegalovirus (HCMV) manipulates host cell signaling pathways using both proteins and noncoding RNAs. Several studies have shown that HCMV induces NF-κB signaling early in infection, resulting in the induction of antiviral proinflammatory cytokines with a subsequent reduction of these cytokines late in infection. The mechanism for late cytokine reduction is unknown. In this study, we show that HCMV microRNAs (miRNAs) miR-US5-1 and miR-UL112-3p target the IκB kinase (IKK) complex components IKKα and IKKβ to limit production of proinflammatory cytokines in response to interleukin 1β (IL-1β) and tumor necrosis factor alpha (TNF-α). Transfection of miR-UL112-3p and miR-US5-1 mimics reduced endogenous IKKα and IKKβ protein levels, and site-directed mutagenesis of the 3′ untranslated regions (UTRs) identified the binding sites for each miRNA. Infection with mutant viruses lacking these miRNAs resulted in increased levels of IKKα and IKKβ proteins, an impaired ability to control NF-κB signaling at late times of lytic infection, and increased production of proinflammatory cytokines compared to wild-type virus in cell types relevant to HCMV infectionin vivo. These phenotypes were rescued by preexpression of miR-US5-1 and miR-UL112-3p in infected cells or by a miR-US5-1/miR-UL112-3p double mutant virus that expresses short hairpin RNAs (shRNAs) targeting IKKα and IKKβ, demonstrating the gene specificity of the miRNAs. These observations describe a mechanism through which HCMV miRNAs expressed late in the infectious cycle downregulate proinflammatory cytokine production to create a cellular proviral environment.IMPORTANCEHuman cytomegalovirus (HCMV) is a significant cause of morbidity and mortality in transplant recipients and causes hearing loss and mental retardation when acquired congenitally. Initial events during HCMV infection result in the activation of NF-κB signaling, which culminates in the production of IL-6, CCL5, and TNF-α. Several viruses have developed mechanisms to block the antiviral effects of these cytokines. We show here that two HCMV miRNAs, miR-US5-1 and miR-UL112-3p, specifically downregulate IKKα and IKKβ signaling factors necessary to propagate NF-κB signaling and subsequent IL-6, CCL5, and TNF-α production. Regulation of these proinflammatory cytokines during lytic infection and during latency is critical to viral survival in the host.

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