Proinflammatory Responses of 1-Nitropyrene against RAW264.7 Macrophages through Akt Phosphorylation and NF-κB Pathways

Air pollution is a major environmental and public health problem worldwide. A nitro-polycyclic aromatic hydrocarbon and the most abundant air pollutant in diesel engine exhaust, 1-nitropyrene (1-NP), is caused by the incomplete combustion of carbonaceous organic substances. Macrophages are effector cells of the innate immune cells that provide resistance in the peripheral tissue. The overactivation of macrophages results in inflammation. The generation of proinflammatory cytokines, such as interleukin (IL)-1β, IL-6, and tumour necrosis factor alpha, is induced by 1-NP in a concentration-dependent manner in macrophages. In this study, the production of proinflammatory mediators, such as nitrogen oxide and prostaglandin E2, was induced by 1-NP in a concentration-dependent manner through the expression of iNOS and COX2. The generation of proinflammatory cytokines, iNOS, and COX2 was induced by 1-NP through nuclear factor (NF)-κB p65 phosphorylation and the degradation of its upstream factor, IκB. Finally, Akt phosphorylation was induced by 1-NP in a concentration-dependent manner. These findings suggest that 1-NP exhibits a proinflammatory response through the NF-κB pathway activation due to Akt phosphorylation.

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Tumor necrosis factor alpha activates soluble guanylate cyclase in bovine glomerular mesangial cells via an L-arginine-dependent mechanism.

Journal of Experimental Medicine ◽

10.1084/jem.172.6.1843 ◽

1990 ◽

Vol 172 (6) ◽

pp. 1843-1852 ◽

Cited By ~ 80

Author(s):

P A Marsden ◽

B J Ballermann

Keyword(s):

Guanylate Cyclase ◽

Mesangial Cell ◽

Soluble Guanylate Cyclase ◽

Mesangial Cells ◽

Tnf Alpha ◽

Dependent Manner ◽

Glomerular Mesangial Cells ◽

Concentration Dependent Manner ◽

Necrosis Factor Alpha ◽

Factor Alpha

Endothelium-derived nitric oxide (NO) causes vasodilatation by activating soluble guanylate cyclase, and glomerular mesangial cells respond to NO with elevations of intracellular guanosine 3',5'-cyclic monophosphate (cGMP). We explored whether mesangial cells can be stimulated to produce NO and whether NO modulates mesangial cell function in an autocrine or paracrine fashion. Tumor necrosis factor alpha (TNF-alpha) raised mesangial cell cGMP levels in a time- and concentration-dependent manner (threshold dose 1 ng/ml, IC50 13.8 ng/ml, maximal response 100 ng/ml). TNF-alpha-induced increases in mesangial cGMP content were evident at 8 h and maximal at 18-24 h. The TNF-alpha-induced stimulation of mesangial cell cGMP production was abrogated by actinomycin D or cycloheximide suggesting dependence on new RNA or protein synthesis. Hemoglobin and methylene blue, both known to inhibit NO action, dramatically reduced TNF-alpha-induced mesangial cell cGMP production. Superoxide dismutase, known to potentiate NO action, augmented the TNF-alpha-induced effect. Ng-monomethyl-L-arginine (L-NMMA) decreased cGMP levels in TNF-alpha-treated, but not vehicle-treated mesangial cells in a concentration-dependent manner (IC50 53 microM). L-arginine had no effect on cGMP levels in control or TNF-alpha-treated mesangial cells but reversed L-NMMA-induced inhibition. Interleukin 1 beta and lipopolysaccharide (LPS), but not interferon gamma, also increased mesangial cell cGMP content. Transforming growth factor beta 1 blunted the mesangial cell response to TNF-alpha. TNF-alpha-induced L-arginine-dependent increases in cGMP were also evident in bovine renal artery vascular smooth muscle cells, COS-1 cells, and 1502 human fibroblasts. These findings suggest that TNF-alpha induces expression in mesangial cell of an enzyme(s) involved in the formation of L-arginine-derived NO. Moreover, the data indicate that NO acts in an autocrine and paracrine fashion to activate mesangial cell soluble guanylate cyclase. Cytokine-induced formation of NO in mesangial and vascular smooth muscle cells may be implicated in the pathogenesis of septic shock.

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Epigallocatechin gallate inhibits endothelial exocytosis

Biological Chemistry ◽

10.1515/bc.2008.095 ◽

2008 ◽

Vol 389 (7) ◽

Cited By ~ 22

Author(s):

Munekazu Yamakuchi ◽

Clare Bao ◽

Marcella Ferlito ◽

Charles J. Lowenstein

Keyword(s):

Endothelial Cells ◽

Green Tea ◽

Umbilical Vein ◽

Vascular Inflammation ◽

Epigallocatechin Gallate ◽

Initial Step ◽

No Production ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Akt Phosphorylation

Abstract Consumption of green tea is associated with a decrease in cardiovascular mortality. The beneficial health effects of green tea are attributed in part to polyphenols, organic compounds found in tea that lower blood pressure, reduce body fat, decrease LDL cholesterol, and inhibit inflammation. We hypothesized that epigallocatechin gallate (EGCG), the most abundant polyphenol in tea, inhibits endothelial exocytosis, the initial step in leukocyte trafficking and vascular inflammation. To test this hypothesis, we treated human umbilical-vein endothelial cells with EGCG and other polyphenols, and then measured endothelial exocytosis. We found that EGCG decreases endothelial exocytosis in a concentration-dependent manner, with the effects most prominent after 4 h of treatment. Other catechin polyphenols had no effect on endothelial cells. By inhibiting endothelial exocytosis, EGCG decreases leukocyte adherence to endothelial cells. In searching for the mechanism by which EGCG affects endothelial cells, we found that EGCG increases Akt phosphorylation, eNOS phosphorylation, and nitric oxide (NO) production. NOS inhibition revealed that NO mediates the anti-inflammatory effects of EGCG. Our data suggest that polyphenols can decrease vascular inflammation by increasing the synthesis of NO, which blocks endothelial exocytosis.

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Methanol Extract ofArtemisia apiaceaHance Attenuates the Expression of Inflammatory Mediators via NF-κB Inactivation

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/494681 ◽

2013 ◽

Vol 2013 ◽

pp. 1-12 ◽

Cited By ~ 9

Author(s):

Ji Choul Ryu ◽

Sang Mi Park ◽

Min Hwangbo ◽

Sung Hui Byun ◽

Sae Kwang Ku ◽

...

Keyword(s):

Nitric Oxide ◽

Therapeutic Potential ◽

Interleukin 1 ◽

Dependent Manner ◽

Nuclear Factor ◽

Paw Edema ◽

Concentration Dependent Manner ◽

Proinflammatory Mediators ◽

Inducible Nitric Oxide

Artemisia apiaceaHance is one of the most widely used herbs for the treatment of malaria, jaundice, and dyspeptic complaint in oriental medicine. This study investigated the effects of methanol extracts ofA. apiaceaHance (MEAH) on the induction of inducible nitric oxide synthase (iNOS) and proinflammatory mediators by lipopolysaccharide (LPS) in Raw264.7 macrophage cells and also evaluated thein vivoeffect of MEAH on carrageenan-induced paw edema in rats. MEAH treatment in Raw264.7 cells significantly decreased LPS-inducible nitric oxide production and the expression of iNOS in a concentration-dependent manner, while MEAH (up to 100 μg/mL) had no cytotoxic activity. Results from immunoblot analyses and ELISA revealed that MEAH significantly inhibited the expression of cyclooxygenase-2, tumor necrosis factor-α, interleukin-1β, and interleukin-6 in LPS-activated cells. As a plausible molecular mechanism, increased degradation and phosphorylation of inhibitory-κBαand nuclear factor-κB accumulation in the nucleus by LPS were partly blocked by MEAH treatment. Finally, MEAH treatment decreased the carrageenan-induced formation of paw edema and infiltration of inflammatory cells in rats. These results demonstrate that MEAH has an anti-inflammatory therapeutic potential that may result from the inhibition of nuclear factor-κB activation, subsequently decreasing the expression of proinflammatory mediators.

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Morphine promotes microglial activation by upregulating the EGFR/ERK signaling pathway

PLoS ONE ◽

10.1371/journal.pone.0256870 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0256870

Author(s):

Yaqiong Yang ◽

Yu Sun ◽

Rong Hu ◽

Jia Yan ◽

Ziheng Wang ◽

...

Keyword(s):

Signaling Pathway ◽

Proinflammatory Cytokines ◽

Microglial Activation ◽

Morphine Tolerance ◽

Erk Signaling ◽

Dependent Manner ◽

Migration Ability ◽

Necrosis Factor Alpha ◽

Egfr Signaling Pathway ◽

Egfr Expression

Although they represent the cornerstone of analgesic therapy, opioids, such as morphine, are limited in efficacy by drug tolerance, hyperalgesia and other side effects. Activation of microglia and the consequent production of proinflammatory cytokines play a key pathogenic role in morphine tolerance, but the exact mechanisms are not well understood. This study aimed to investigate the regulatory mechanism of epidermal growth factor receptor (EGFR) on microglial activation induced by morphine in mouse microglial BV-2 cells. In this research, BV-2 cells were stimulated with morphine or pretreated with AG1478 (an inhibitor of EGFR). Expression levels of cluster of differentiation molecule 11b (CD11b), EGFR, and phospho-EGFR were detected by immunofluorescence staining. Cell signaling was assayed by Western blot. The migration ability of BV-2 cells was tested by Transwell assay. The production of interleukin-1beta (IL-1β) and tumor necrosis factor-alpha (TNF-α) in the cell supernatant was determined by ELISA. We observed that the expression of CD11b induced by morphine was increased in a dose- and time- dependent manner in BV-2 cells. Phosphorylation levels of EGFR and ERK1/2, migration of BV-2 cells, and production of IL-1β and TNFα were markedly enhanced by morphine treatment. The activation, migration, and production of proinflammatory cytokines in BV-2 cells were inhibited by blocking the EGFR signaling pathway with AG1478. The present study demonstrated that the EGFR/ERK signaling pathway may represent a novel pharmacological strategy to suppress morphine tolerance through attenuation of microglial activation.

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Bioactive Diarylheptanoids from Alpinia coriandriodora

Natural Products and Bioprospecting ◽

10.1007/s13659-020-00264-y ◽

2020 ◽

Author(s):

Xiao-Li Cheng ◽

Han-Xiang Li ◽

Juan Chen ◽

Ping Wu ◽

Jing-Hua Xue ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Spectroscopic Analysis ◽

Raw 264.7 Cells ◽

Raw 264.7 ◽

Dependent Manner ◽

Oxygen Species ◽

Edible Plant ◽

Concentration Dependent Manner ◽

Raw264.7 Macrophages ◽

No Release

Abstract Eight new diarylheptanoids, coriandralpinins A–H (1–8), were isolated from the rhizomes of Alpinia coriandriodora, an edible plant of the ginger family. Their structures, including the absolute configurations, were established by extensive spectroscopic analysis and ECD calculations. Compounds 1–8 have a 1,5-O-bridged diarylheptanoid structure featuring polyoxygenated aryl units. When evaluated for intracellular antioxidant activity using t-BHP stressed RAW264.7 macrophages, all these compounds scavenged reactive oxygen species (ROS) in a concentration-dependent manner. Compounds 3 and 5 also showed inhibitory activity against NO release in LPS-induced RAW 264.7 cells. Six known flavonols, 7,4′-di-O-methylkaempferol, 7-O-methylquercetin, 7,4′-di-O-methylquercetin, 7,3′,4′-tri-O- methylquercetin, kaempferol 3-O-β-d-(6-O-α-l-rhamnopyranosyl)glucopyranoside, and 3-O-β-d-glucopyranuronosylquercetin were also isolated and characterized from the rhizomes.

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Topical Anti-Inflammatory Activity of Essential Oils of Alpinia calcarata Rosc., Its Main Constituents, and Possible Mechanism of Action

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2020/2035671 ◽

2020 ◽

Vol 2020 ◽

pp. 1-19

Author(s):

Madhuvanthi Chandrakanthan ◽

Shiroma M. Handunnetti ◽

Galbada Sirimal Arachchige Premakumara ◽

Selvaluxmy Kathirgamanathar

Keyword(s):

Skin Inflammation ◽

Inflammatory Activity ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Proinflammatory Mediators ◽

Mouse Ear ◽

Anti Inflammatory ◽

Dose Dependent ◽

Topical Analgesic

This study aimed at investigating the anti-inflammatory potential of essential oil from rhizome and leaf of Alpinia calcarata Rosc. (ACEO) with the focus of its topical anti-inflammatory activity along with its dominant compounds 1,8-cineole and α-terpineol using mouse ear edema model. ACEOs were analyzed by GC-MS. The anti-inflammatory activity was determined by studying the inhibition of overproduction of proinflammatory mediators—nitric oxide, reactive oxygen species, prostaglandins, cyclooxygenases, and cytokines induced by lipopolysaccharides in murine macrophages. Topical anti-inflammatory and antinociceptive activity was studied by 12-O-tetradecanoylphorbol-13-acetate (TPA) induced skin inflammation and formalin-induced pain model in mice, respectively. Rhizome oil has 1,8-cineole (31.08%), α-terpineol (10.31%), and fenchyl acetate (10.73%) as major compounds whereas the ACEO from leaves has 1,8-cineole (38.45%), a-terpineol (11.62%), and camphor (10%). ACEOs reduced the production of inflammatory mediators in vitro in a concentration-dependent manner. Further, ACEO and its major compounds reduced ear thickness, weight, myeloperoxidase, and cytokines significantly (p<0.01) in mouse ear. Dose-dependent reduction in flinching and licking in both the phases of pain sensation concludes the topical analgesic effect. Our findings suggest the potency of topical use of ACEOs for inflammatory disease conditions.

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Abstract 323: A Peptide Inhibitor of PTEN Improves Mouse Survival After Cardiac Arrest

Circulation ◽

10.1161/circ.138.suppl_2.323 ◽

2018 ◽

Vol 138 (Suppl_2) ◽

Author(s):

Xiangdong Zhu ◽

Jing Li ◽

Huashan Wang ◽

Chunpei Lee ◽

Zhiyi Zhu ◽

...

Keyword(s):

Cardiac Arrest ◽

Mouse Model ◽

Glucose Utilization ◽

Polyol Pathway ◽

Treated Group ◽

Inhibitory Effect ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Akt Phosphorylation ◽

Akt Activation

Introduction: Prior works from our laboratory found that cooling protection after cardiac arrest is mediated by enhanced Akt activation and in cardiomyocyte the cooling protection can be reproduced using PTEN chemical inhibitor. The current study extend these works by designing a cell-permeable peptide, TAT-PTEN9c, which is more specific for PTEN. Hypothesis: We hypothesized that TAT-PTEN9c interferes with endogenous PTEN binding to cell membrane adaptor resulting in increased Akt activation, enhanced glucose utilization and improved mouse survival after cardiac arrest. Methods: Mouse cardiomyocytes were isolated from 1-3 day old mouse pups. Western blot was used to determine the efficacy of TAT-PTEN9c for Akt activation. The effect of TAT-PTEN9c on mouse survival after cardiac arrest was determined in a mouse model. TAT-PTEN9c (7.5 mg/kg) was given intravenously (IV) after CPR. As a measure of impaired glucose utilization, sorbitol content in heart and brain was determined by a fluorescence assay of NADH formation using sorbitol dehydrogenase and NAD + . Results: TAT-PTEN9c peptide enhanced Akt activation in mouse cardiomyocytes in a concentration-dependent manner. Akt phosphorylation was observed at 1 μM and further increased with 10 μM TAT-PTEN9c. TAT-PTEN9c blocked the binding of endogenous PTEN to MAGI2 in a co-immunoprecipitation assay, while TAT-PTEN3a control had no inhibitory effect. In a mouse model of cardiac arrest, survival was significantly increased in the TAT-PTEN9c treated group compared to saline controls at 4 h (10/15, 67% vs. 6/15, 40%, P < 0.05) after CPR. TAT-PTEN9c improved MAP at both R30 min and R2h. The treated mice had increased Akt phosphorylation at R15 min in both heart and brain tissues with significantly decreased sorbitol content and reduced release of taurine and glutamate into blood, suggesting improved metabolic recovery and glucose utilization. Conclusion: TAT-PTEN9c can be used after CPR in a mouse SCA model to rapidly enhance Akt activation and decrease glucose shunting to the polyol pathway in critical organs, preventing osmotic injury and early cardiovascular collapse and death.

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Infiltrating Macrophages Are Key to the Development of Seizures following Virus Infection

Journal of Virology ◽

10.1128/jvi.02747-12 ◽

2012 ◽

Vol 87 (3) ◽

pp. 1849-1860 ◽

Cited By ~ 62

Author(s):

Matthew F. Cusick ◽

Jane E. Libbey ◽

Dipan C. Patel ◽

Daniel J. Doty ◽

Robert S. Fujinami

Keyword(s):

Proinflammatory Cytokines ◽

Neuronal Excitability ◽

Viral Infections ◽

Cell Types ◽

Proinflammatory Response ◽

Necrosis Factor Alpha ◽

Antiviral Immune Response ◽

Acute Seizures ◽

Tnf Α ◽

The Central Nervous System

ABSTRACTViral infections of the central nervous system (CNS) can trigger an antiviral immune response, which initiates an inflammatory cascade to control viral replication and dissemination. The extent of the proinflammatory response in the CNS and the timing of the release of proinflammatory cytokines can lead to neuronal excitability. Tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), two proinflammatory cytokines, have been linked to the development of acute seizures in Theiler's murine encephalomyelitis virus-induced encephalitis. It is unclear the extent to which the infiltrating macrophages versus resident CNS cells, such as microglia, contribute to acute seizures, as both cell types produce TNF-α and IL-6. In this study, we show that following infection a significantly higher number of microglia produced TNF-α than did infiltrating macrophages. In contrast, infiltrating macrophages produced significantly more IL-6. Mice treated with minocycline or wogonin, both of which limit infiltration of immune cells into the CNS and their activation, had significantly fewer macrophages infiltrating the brain, and significantly fewer mice had seizures. Therefore, our studies implicate infiltrating macrophages as an important source of IL-6 that contributes to the development of acute seizures.

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Porphyromonas gingivalis RgpA-Kgp Proteinase-Adhesin Complexes Penetrate Gingival Tissue and Induce Proinflammatory Cytokines or Apoptosis in a Concentration-Dependent Manner

Infection and Immunity ◽

10.1128/iai.01038-08 ◽

2008 ◽

Vol 77 (3) ◽

pp. 1246-1261 ◽

Cited By ~ 65

Author(s):

Neil M. O'Brien-Simpson ◽

Rishi D. Pathirana ◽

Glenn D. Walker ◽

Eric C. Reynolds

Keyword(s):

Connective Tissue ◽

Porphyromonas Gingivalis ◽

Intercellular Adhesion Molecule ◽

Gingival Tissue ◽

Dependent Manner ◽

Intercellular Adhesion Molecule 1 ◽

Concentration Dependent Manner ◽

Proinflammatory Mediators ◽

Low Concentrations ◽

High Concentrations

ABSTRACT The RgpA-Kgp proteinase-adhesin complexes of Porphyromonas gingivalis were observed, using immunostaining, in human gingival tissue associated with periodontitis but not in healthy tissue. The staining pattern suggested a concentration gradient from the subgingival plaque into the subjacent gingival connective tissue. Intense immunostaining was observed in areas displaying gross disturbance of tissue architecture. P. gingivalis cells and the RgpA-Kgp complexes at low concentrations were shown to stimulate secretory intercellular adhesion molecule 1, interleukin-8 (IL-8), IL-6, and macrophage chemoattractant protein secretion from cultured human epithelial (KB) and fibroblast (MRC-5) cells. However, at high concentrations a reduction in the level of these mediators was observed. In contrast, macrophage inflammatory protein 1α and IL-1α were stimulated only at high P. gingivalis cell concentrations. P. gingivalis cells and the RgpA-Kgp complexes were shown to induce apoptosis in KB and MRC-5 cells in a time- and dose-dependent manner. These data suggest that the RgpA-Kgp complexes penetrate the gingival connective tissue; at low concentrations distal from the plaque the complexes stimulate the secretion of proinflammatory mediators, while at high concentrations proximal to the plaque they induce apoptosis and attenuate the secretion of proinflammatory mediators.

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Effect of Moxifloxacin on Production of Proinflammatory Cytokines from Human Peripheral Blood Mononuclear Cells

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.12.3704-3707.2003 ◽

2003 ◽

Vol 47 (12) ◽

pp. 3704-3707 ◽

Cited By ~ 27

Author(s):

Jung-Hyun Choi ◽

Min-Jin Song ◽

Seung-Han Kim ◽

Su-Mi Choi ◽

Dong-Gun Lee ◽

...

Keyword(s):

Proinflammatory Cytokines ◽

Peripheral Blood Mononuclear Cells ◽

Peripheral Blood ◽

Mononuclear Cells ◽

Human Peripheral Blood ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Peripheral Blood Mononuclear ◽

Tnf Α ◽

Blood Mononuclear Cells

ABSTRACT The effects of moxifloxacin, a new methoxyfluoroquinolone, on the production of proinflammatory cytokines from human peripheral blood mononuclear cells (PBMCs) were evaluated. Moxifloxacin inhibited the production of tumor necrosis factor alpha (TNF-α) and/or interleukin-6 (IL-6) by PBMCs stimulated with lipopolysaccharide (LPS), lipoteichoic acid (LTA), and heat-killed bacteria in a concentration-dependent manner without cytotoxic effects. The addition of moxifloxacin reduced the population of cells positive for CD-14 and TNF-α and for CD-14 and IL-6 among the LPS- or LTA-stimulated PBMCs. By Western blot analysis, moxifloxacin pretreatment reduced the degradation of IκBα in LPS-stimulated PBMCs. In conclusion, moxifloxacin could interfere with NF-κB activation by inhibiting the degradation of IκBα and reduce the levels of production of proinflammatory cytokines.

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