scholarly journals PARP Traps Rescue the Pro-Inflammatory Response of Human Macrophages in the In Vitro Model of LPS-Induced Tolerance

2021 ◽  
Vol 14 (2) ◽  
pp. 170
Author(s):  
Julita Pietrzak ◽  
Karolina Gronkowska ◽  
Agnieszka Robaszkiewicz
Keyword(s):  
Intracellular Signaling ◽  
Gene Promoter ◽  
Proinflammatory Response ◽  
Human Macrophages ◽  
Intracellular Signaling Pathway ◽  
Tnf Α ◽  
Cell Pretreatment ◽  
Vitro Model ◽  
Induced Tolerance

Secondary infections cause sepsis that lead to patient disability or death. Contact of macrophages with bacterial components (such as lipopolysaccharide—LPS) activates the intracellular signaling pathway downstream of Toll-like receptors (TLR), which initiate an immune proinflammatory response. However, the expression of nuclear factor-kappa B (NF-κB)-dependent proinflammatory cytokines significantly decreases after single high or multiple LPS stimulations. Knowing that poly(ADP-ribose) polymerase-1 (PARP1) serves as a cofactor of NF-κB, we aimed to verify a hypothesis of the possible contribution of PARP1 to the development of LPS-induced tolerance in human macrophages. Using TNF-α mRNA expression as a readout, we demonstrate that PARP1 interaction with the TNF-α promoter, controls macrophage immunoparalysis. We confirm that PARP1 is extruded from the gene promoter, whereas cell pretreatment with Olaparib maintains macrophage responsiveness to another LPS treatment. Furthermore, cell pretreatment with proteasome inhibitor MG132 completely abrogates the effect of Olaparib, suggesting that PARP1 acts with NF-κB in the same regulatory pathway, which controls pro-inflammatory cytokine transcription. Mechanistically, PARP1 trapping allows for the re-rebinding of p65 to the TNF-α promoter in LPS-stimulated cells. In conclusion, PARP traps prevent PARP1 extrusion from the TNF-α promoter upon macrophage stimulation, thereby maintaining chromatin responsiveness of TLR activation, allowing for the re-binding of p65 and TNF-α transcription.

scholarly journals Antioxidant and Hypolipidemic Activity of Açai Fruit Makes It a Valuable Functional Food

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Anna Virginia Adriana Pirozzi ◽  
Paola Imbimbo ◽  
Antonella D’Agostino ◽  
Virginia Tirino ◽  
Rosario Finamore ◽  
...  
Keyword(s):  
Functional Food ◽  
Subcutaneous Fat ◽  
Cell Models ◽  
Alcoholic Fatty Liver ◽  
Hypoxic Conditions ◽  
Tnf Α ◽  
Different Types ◽  
Vitro Model ◽  
Alcoholic Fatty Liver Disease

Several plant extracts are acquiring increasing value because of their antioxidant activity and hypolipidemic properties. Among them, great interest has been recently paid to açai fruit as a functional food. The aim of this study was to test the ability of açai extract in reducing oxidative stress and modulating lipid metabolism in vitro using different cell models and different types of stress. In fact, lipid peroxidation as evaluated in a HepG2 model was reduced five-fold when using 0.25 µg/mL of extract, and it was further reduced (20-fold) with the concentration increase up to 2.5 µg/mL. With the non alcoholic fatty liver disease (NAFLD)in vitro model, all concentrations tested showed at least a two-fold reduced fat deposit. In addition, primary adipocytes challenged with TNF-α under hypoxic conditions to mimic the persistent subcutaneous fat, treated with açai extract showed an approximately 40% reduction of fat deposit. Overall, our results show that açai is able to counteract oxidative states in all the cell models analysed and to prevent the accumulation of lipid droplets. No toxic effects and high stability overtime were highlighted at the concentrations tested. Therefore, açai can be considered a suitable support in the prevention of different alterations of lipid and oxidative metabolism responsible for fat deposition and metabolic pathological conditions.

scholarly journals Activation of the receptor tyrosine kinase RET improves long-term hematopoietic stem cell outgrowth and potency

Blood ◽  
2020 ◽  
Vol 136 (22) ◽  
pp. 2535-2547 ◽  
Author(s):  
W. Grey ◽  
R. Chauhan ◽  
M. Piganeau ◽  
H. Huerga Encabo ◽  
M. Garcia-Albornoz ◽  
...  
Keyword(s):  
Intracellular Signaling ◽  
Culture Conditions ◽  
Cellular Growth ◽  
Great Promise ◽  
Bone Marrow Niche ◽  
Hematopoietic Stem ◽  
Intracellular Signaling Pathway ◽  
Wide Range

Abstract Expansion of human hematopoietic stem cells (HSCs) is a rapidly advancing field showing great promise for clinical applications. Recent evidence has implicated the nervous system and glial family ligands (GFLs) as potential drivers of hematopoietic survival and self-renewal in the bone marrow niche; how to apply this process to HSC maintenance and expansion has yet to be explored. We show a role for the GFL receptor, RET, at the cell surface of HSCs in mediating sustained cellular growth, resistance to stress, and improved cell survival throughout in vitro expansion. HSCs treated with the key RET ligand/coreceptor complex, glial-derived neurotrophic factor and its coreceptor, exhibit improved progenitor function at primary transplantation and improved long-term HSC function at secondary transplantation. Finally, we show that RET drives a multifaceted intracellular signaling pathway, including key signaling intermediates protein kinase B, extracellular signal-regulated kinase 1/2, NF-κB, and p53, responsible for a wide range of cellular and genetic responses that improve cell growth and survival under culture conditions.

scholarly journals Inhibition of the phosphoinositide 3-kinase-AKT-cyclic GMP-c-Jun N-terminal kinase signaling pathway attenuates the development of morphine tolerance in a mouse model of neuropathic pain

2021 ◽  
Vol 17 ◽  
pp. 174480692110033
Author(s):  
Travis Okerman ◽  
Taylor Jurgenson ◽  
Madelyn Moore ◽  
Amanda H Klein
Keyword(s):  
Spinal Cord ◽  
Sciatic Nerve ◽  
Signaling Pathway ◽  
Intracellular Signaling ◽  
Morphine Tolerance ◽  
Spinal Nerve ◽  
Intracellular Signaling Pathway ◽  
Spinal Cord Dorsal ◽  
Phosphoinositide 3 Kinase ◽  
Induced Tolerance

Research presented here sought to determine if opioid induced tolerance is linked to activity changes within the PI3Kγ-AKT-cGMP-JNK intracellular signaling pathway in spinal cord or peripheral nervous systems. Morphine or saline injections were given subcutaneously twice a day for five days (15 mg/kg) to male C57Bl/6 mice. A separate cohort of mice received spinal nerve ligation (SNL) one week prior to the start of morphine tolerance. Afterwards, spinal cord, dorsal root ganglia, and sciatic nerves were isolated for quantifying total and phosphorylated- JNK levels, cGMP, and gene expression analysis of Pik3cg, Akt1, Pten, and nNos1. This pathway was downregulated in the spinal cord with increased expression in the sciatic nerve of morphine tolerant and morphine tolerant mice after SNL. We also observed a significant increase in phosphorylated- JNK levels in the sciatic nerve of morphine tolerant mice with SNL. Pharmacological inhibition of PI3K or JNK, using thalidomide, quercetin, or SP600125, attenuated the development of morphine tolerance in mice with SNL as measured by thermal paw withdrawal. Overall, the PI3K/AKT intracellular signaling pathway is a potential target for reducing the development of morphine tolerance in the peripheral nervous system. Continued research into this pathway will contribute to the development of new analgesic drug therapies.

scholarly journals Ureaplasma urealyticum Modulates Endotoxin-Induced Cytokine Release by Human Monocytes Derived from Preterm and Term Newborns and Adults

2001 ◽  
Vol 69 (6) ◽  
pp. 3906-3915 ◽  
Author(s):  
Winston M. Manimtim ◽  
Jeffrey D. Hasday ◽  
Lisa Hester ◽  
Karen D. Fairchild ◽  
Judith C. Lovchik ◽  
...  
Keyword(s):  
Proinflammatory Cytokines ◽  
Ureaplasma Urealyticum ◽  
Human Monocytes ◽  
Cytokine Release ◽  
Proinflammatory Response ◽  
Pediatr Infect ◽  
High Inoculum ◽  
Tnf Α ◽  
Adult Cells

ABSTRACT We previously observed that Ureaplasma urealyticumrespiratory tract colonization in infants with a birth weight of ≤1,250 g was associated with increases in the tracheal aspirate proinflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8) relative to the counterregulatory cytokine IL-6 during the first week of life (A. M. Patterson, V. Taciak, J. Lovchik, R. E. Fox, A. B. Campbell, and R. M. Viscardi, Pediatr. Infect. Dis. J. 17:321–328, 1998). We hypothesized thatU. urealyticum alters the host immune response in the presence of a coinflammatory stimulus (e.g., bacterial infection or hyperoxia) by shifting the balance of cytokine expression towards the proinflammatory cytokines. To test this hypothesis, we compared the release of TNF-α, IL-8, IL-6, and IL-10 in vitro by unstimulated andU. urealyticum (with or without lipopolysaccharide [LPS])-stimulated human monocytes from adult peripheral blood and from term and preterm cord blood. U. urealyticum alone and in combination with LPS induced concentration- and development-dependent changes in cytokine release. In vitro inoculation with low-inoculum U. urealyticum (103color-changing units [CCU]) (i) partially blocked the LPS-stimulated IL-6 release by all cells and reduced LPS-stimulated IL-10 release by preterm cells, (ii) stimulated TNF-α and IL-8 release by preterm cells, and (iii) augmented LPS-stimulated TNF-α release in all cells. In preterm cells, high-inoculum U. urealyticum(106 CCU) (i) stimulated TNF-α and IL-8, but not IL-6 or IL-10, release and (ii) augmented LPS-stimulated TNF-α and IL-8 release. High-inoculum U. urealyticum (i) stimulated release of all four cytokines in term cells and IL-8 release in adult cells and (ii) augmented LPS-induced TNF-α, IL-10, and IL-8 release in term cells but did not significantly affect LPS-induced cytokine release in adult cells. We speculate that U. urealyticum enhances the proinflammatory response to a second infection by blocking expression of counterregulatory cytokines (IL-6 and IL-10), predisposing the preterm infant to prolonged and dysregulated inflammation, lung injury, and impaired clearance of secondary infections.

scholarly journals Effect of the proinflammatory cytokine TNF-α on intestinal riboflavin uptake: inhibition mediated via transcriptional mechanism(s)

2018 ◽  
Vol 315 (5) ◽  
pp. C653-C663 ◽  
Author(s):  
Kasin Yadunandam Anandam ◽  
Omar A. Alwan ◽  
Veedamali S. Subramanian ◽  
Padmanabhan Srinivasan ◽  
Rubina Kapadia ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Significant Inhibition ◽  
Mrna Levels ◽  
In Vivo Models ◽  
Uptake Inhibition ◽  
Tnf Α ◽  
Vitro Model ◽  
Factor Α

Riboflavin (RF), is essential for normal cellular metabolism/function. Intestinal RF absorption occurs via a specific carrier-mediated process that involves the apical transporter RFVT-3 ( SLC52A3) and the basolateral RFVT-1 (SLC52A1). Previously, we characterized different cellular/molecular aspects of the intestinal RF uptake process, but nothing is known about the effect of proinflammatory cytokines on the uptake event. We addressed this issue using in vitro, ex vivo, and in vivo models. First, we determined the level of mRNA expression of the human (h)RFVT-3 and hRFVT-1 in intestinal tissue of patients with inflammatory bowel disease (IBD) and observed a markedly lower level compared with controls. In the in vitro model, exposing Caco-2 cells to tumor necrosis factor-α (TNF-α) led to a significant inhibition in RF uptake, an effect that was abrogated upon knocking down TNF receptor 1 (TNFR1). The inhibition in RF uptake was associated with a significant reduction in the expression of hRFVT-3 and -1 protein and mRNA levels, as well as in the activity of the SLC52A3 and SLC52A1 promoters. The latter effects appear to involve Sp1 and NF-κB sites in these promoters. Similarly, exposure of mouse small intestinal enteroids and wild-type mice to TNF-α led to a significant inhibition in physiological and molecular parameters of intestinal RF uptake. Collectively, these findings demonstrate that exposure of intestinal epithelial cells to TNF-α leads to inhibition in RF uptake and that this effect is mediated, at least in part, via transcriptional mechanism(s). These findings may explain the significantly low RF levels observed in patients with IBD.

Differential expression and regulation of ADAM17 and TIMP3 in acute inflamed intestinal epithelia

2009 ◽  
Vol 296 (6) ◽  
pp. G1332-G1343 ◽  
Author(s):  
Annabelle Cesaro ◽  
Abakar Abakar-Mahamat ◽  
Patrick Brest ◽  
Sandra Lassalle ◽  
Eric Selva ◽  
...  
Keyword(s):  
High Activity ◽  
Early Phase ◽  
Active Form ◽  
Tissue Inhibitor Of Metalloproteinase ◽  
Intestinal Epithelial ◽  
T84 Cells ◽  
Intestinal Epithelia ◽  
Tnf Α ◽  
Vitro Model

The acute phase of Crohn's disease (CD) is characterized by a large afflux of polymorphonuclear leukocytes (PMNL) into the mucosa and by the release of TNF-α. Conversion of inactive TNF-α into an active form requires the cleavage of a transmembrane TNF-α precursor by the TNF-α-converting enzyme (ADAM17), a protease mainly regulated by the tissue inhibitor of metalloproteinase 3 (TIMP3). The aim of the present study was to investigate in an in vitro model of PMNL transepithelial migration and in the intestinal mucosa of patients with CD the expression and regulation of ADAM17 and TIMP3 in intestinal epithelial cells (IEC). ADAM17 and TIMP3 expression was analyzed by Western blotting, RT-PCR, confocal microscopy, and immunohistochemistry by using the T84 model and digestive biopsies. ADAM17 expression in IEC was increased at a posttranscriptional level during the early phase (from 2 to 4 h) of PMNL transepithelial migration whereas TIMP3 was only increased 24 h later. TNF-α induced an early upregulation of ADAM17 in T84 cells, whereas PMNL adhesion, H2O2, or epithelial tight junction opening alone did not affect the amount of ADAM17. Immunohistochemistry of intestinal biopsies revealed that strong expression of ADAM17 was associated with a high activity of CD. In contrast, TIMP3 was very poorly expressed in these biopsies. ADAM17 and TIMP3 profiling did not correlated with the NOD2/CARD15 status. The ADAM17 activity was higher both in the early phase of PMNL transepithelial migration and in active CD. These results showed early posttranscriptional upregulation of ADAM17 in IEC linked to PMNL transepithelial migration and a high activity of CD.

scholarly journals Akt Inhibitor Akt-IV Blocks Virus Replication through an Akt-Independent Mechanism

2009 ◽  
Vol 83 (22) ◽  
pp. 11665-11672 ◽  
Author(s):  
Ewan F. Dunn ◽  
Rachel Fearns ◽  
John H. Connor
Keyword(s):  
Signaling Pathway ◽  
Virus Replication ◽  
Intracellular Signaling ◽  
Akt Pathway ◽  
Akt Inhibitor ◽  
Antiviral Compound ◽  
Intracellular Signaling Pathway ◽  
Cytopathic Effects ◽  
Syncytial Virus

ABSTRACT Many viruses activate the phosphatidylinositol 3′-kinase (PI3k)/Akt intracellular signaling pathway to promote viral replication. We have analyzed whether a rapidly replicating rhabdovirus, vesicular stomatitis virus (VSV), requires the PI3k/Akt signaling pathway for its replication. Through the use of chemical inhibitors of PI3k and Akt, we show that VSV replication and cytopathic effects do not require activation of these kinases. Inhibitors that block the activating phosphorylations of Akt at threonine 308 (Thr308) and serine 473 (Ser473) did not inhibit VSV protein expression or the induction of the cytopathic effects of VSV. One compound, Akt inhibitor Akt-IV, inhibited the replication of VSV, respiratory syncytial virus, and vaccinia virus but increased the phosphorylation of Akt at positions Thr308 and Ser473 and did not inhibit Akt kinase activity in vitro. Together, our data suggest that the PI3k/Akt pathway is of limited relevance to the replication of VSV but that Akt inhibitor Akt-IV is a novel broad-spectrum antiviral compound with a mechanism differing from that of its previously reported effect on the PI3k/Akt pathway. Identification of other targets for this compound may define a new approach for blocking virus replication.

scholarly journals A Novel Lactic Acid Bacteria Mixture: Macrophage-Targeted Prophylactic Intervention in Colorectal Cancer Management

2020 ◽  
Vol 8 (3) ◽  
pp. 387
Author(s):  
Petra Hradicka ◽  
Jane Beal ◽  
Monika Kassayova ◽  
Andrew Foey ◽  
Vlasta Demeckova
Keyword(s):  
Colorectal Cancer ◽  
Male Rats ◽  
Cancer Management ◽  
Immune Parameters ◽  
Chemically Induced ◽  
Tnf Α ◽  
Vitro Model ◽  
Macrophage Subsets

Colorectal cancer (CRC) is one of the most common forms of cancer. Its onset from chronic inflammation is widely accepted. Moreover, dysbiosis plays an undeniable role, thus the use of probiotics in CRC has been suggested. They exhibit both anti- and pro-inflammatory properties and restore balance in the microbiota. The aim of this study was to investigate the immunomodulatory properties of six lactobacilli with probiotic features in an in vitro model of macrophage-like cells and to test these pooled probiotics for their anti-tumour properties in a chemically induced CRC model using Wistar male rats. Upon co-culture of M1- and M2-like macrophages with lactobacilli, cytokine release (TNF-α, IL-1β, IL-18, IL-23) and phagocytic activity using fluorescent-labelled bacteria were tested. The effects of orally administered probiotics on basic cancer and immune parameters and cytokine concentration (TNF-α, IL-1β, IL-18) in colon tumours were studied. Tested lactobacilli exhibited both pro- and anti-inflammatory properties in in vitro conditions. In vivo study showed that the administration of probiotics was able to decrease multiplicity, volume and total tumour numbers, restore colon length (p < 0.05) and increase IL-18 production (p < 0.05) in tumour tissue. These data indicate both an immunomodulatory effect of probiotics on distinct macrophage subsets and a protective effect against chemically-induced CRC.

scholarly journals Quercetin Induces Apoptosis of Trypanosoma brucei gambiense and Decreases the Proinflammatory Response of Human Macrophages

2004 ◽  
Vol 48 (3) ◽  
pp. 924-929 ◽  
Author(s):  
Maria Mamani-Matsuda ◽  
Jérôme Rambert ◽  
Denis Malvy ◽  
Hélène Lejoly-Boisseau ◽  
Sylvie Daulouède ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Trypanosoma Brucei ◽  
Annexin V ◽  
Proinflammatory Response ◽  
Human Macrophages ◽  
Trypanosoma Brucei Gambiense ◽  
Tnf Α ◽  
Normal Human Cell ◽  
Normal Human ◽  
Dose Dependent

ABSTRACT In addition to parasite spread, the severity of disease observed in cases of human African trypanosomiasis (HAT), or sleeping sickness, is associated with increased levels of inflammatory mediators, including tumor necrosis factor (TNF)-α and nitric oxide derivatives. In the present study, quercetin (3,3′,4′,5,7-pentahydroxyflavone), a potent immunomodulating flavonoid, was shown to directly induce the death of Trypanosoma brucei gambiense, the causative agent of HAT, without affecting normal human cell viability. Quercetin directly promoted T. b. gambiense death by apoptosis as shown by Annexin V binding. In addition to microbicidal activity, quercetin induced dose-dependent decreases in the levels of TNF-α and nitric oxide produced by activated human macrophages. These results highlight the potential use of quercetin as an antimicrobial and anti-inflammatory agent for the treatment of African trypanomiasis.

Beneficial effects of nontoxic ozone on H2O2-induced stress and inflammation

2016 ◽  
Vol 94 (6) ◽  
pp. 577-583 ◽  
Author(s):  
Altug Kucukgul ◽  
Suat Erdogan ◽  
Ramazan Gonenci ◽  
Gonca Ozan
Keyword(s):  
Cell Loss ◽  
Alveolar Cells ◽  
Sod Activity ◽  
Beneficial Effects ◽  
Tnf Α ◽  
Ozone Pretreatment ◽  
Anti Oxidant ◽  
Anti Inflammatory ◽  
Vitro Model

In this study, the anti-oxidant and anti-inflammatory efficacy of ozone oxidative preconditioning (OOP) were investigated on hydrogen peroxide (H2O2)-induced human lung alveolar cells. In MTT and trypan blue viability tests, while 100 μmol/L H2O2caused a 17.3% and 21.9% decrease in the number of living cells, respectively, ozone at 20 μmol/L regenerated cell proliferation and prevented 9.6% and 11.0% of cell loss, respectively. In addition, H2O2decreased the transcription levels of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) 5.43-, 2.89-, and 5.33-fold, respectively, while it increased Bax, NF-κβ, TNF-α, and iNOS expression 1.57-, 1.32-, 1.40-, and 1.41-fold, respectively. Ozone pretreatment, however, increased CAT, GPx, and SOD transcription levels 7.08-, 5.17-, and 6.49-fold and decreased Bax, NF-κβ, TNF-α, and iNOS transcriptions by 1.25-, 0.76-, 3.63-, and 7.91-fold, respectively. Moreover, intracellular glutathione (GSH) level and SOD activity were decreased by 46.2% and 45.0% in the H2O2treatment group, and OOP recovered 58.5% and 20.1% of the decreases caused by H2O2. H2O2also increased nitrite levels 7.84-fold, and OOP reduced this increase by half. Consequently, OOP demonstrated potent anti-oxidant and anti-inflammatory effects on in vitro model of oxidative stress-induced lung injury.

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