scholarly journals Effect of Estragole on Leukocyte Behavior and Phagocytic Activity of Macrophages

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Francielli Maria de Souza Silva-Comar ◽  
Luiz Alexandre Marques Wiirzler ◽  
Saulo Euclides Silva-Filho ◽  
Raquel Kummer ◽  
Raissa Bocchi Pedroso ◽  
...  
Keyword(s):  
Phagocytic Activity ◽  
Neutrophil Migration ◽  
Chemical Constituent ◽  
No Production ◽  
Aromatic Plants ◽  
Food Industries ◽  
Adherent Leukocytes ◽  
Peritonitis Model

Estragole, a chemical constituent of the essential oils of many aromatic plants, is used as flavoring in beverage and food industries.In vivoandin vitroexperimental assays have shown that EST has sedative, anticonvulsant, antioxidant, antimicrobial, and anesthetic activity. In this work, we evaluate the effect of EST on leukocyte behavior and phagocytic activity of macrophages. In the peritonitis model, EST (500 and 750 mg/kg) decreased the infiltration of peritoneal exudate leukocytes.In vitrochemotaxis assay showed that EST (3, 10, 30, and 60 μg/mL) inhibited neutrophil migration toward fMLP. In thein vivomicrocirculation assay, EST at doses of 250, 500, and 750 mg/kg significantly reduced the number of rolling and adherent leukocytes and at doses of 250 and 500 mg/kg decreased number of leukocyte migrated to perivascular tissue. The results showed that EST (3, 10, and 30 μg/mL) was able to stimulate the macrophages phagocytosis but only at concentration of 10 μg/mL promoted an increase in nitric oxide (NO) production. In conclusion, this study showed that EST had potential anti-inflammatory effects, likely by inhibiting leukocyte migration and by stimulating macrophages phagocytosis.

ICAM-2 mediates neutrophil transmigration in vivo: evidence for stimulus specificity and a role in PECAM-1–independent transmigration

Blood ◽  
2006 ◽  
Vol 107 (12) ◽  
pp. 4721-4727 ◽  
Author(s):  
Miao-Tzu Huang ◽  
Karen Y. Larbi ◽  
Christoph Scheiermann ◽  
Abigail Woodfin ◽  
Nicole Gerwin ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Leukocyte Adhesion ◽  
Neutrophil Migration ◽  
Selective Reduction ◽  
Leukocyte Transmigration ◽  
Tnf Α ◽  
Peritonitis Model ◽  
Deficient Mice

AbstractICAM-2 has been implicated in leukocyte transmigration in vitro, but there is little in vivo evidence to support this. To address this, neutrophil migration was investigated in ICAM-2–deficient mice (KO) and in wild-type (WT) mice treated with an anti–ICAM-2 blocking monoclonal antibody (mAb) (3C4). In a peritonitis model, IL-1β–induced accumulation of neutrophils was significantly reduced in mice treated with 3C4 (51% inhibition) and in KO mice (41% inhibition). In contrast, TNF-α– or thioglycolate-induced responses were not suppressed in KO mice. Analysis of IL-1β–induced leukocyte responses in cremasteric venules of KO animals by intravital microscopy indicated a defect in transmigration (44% inhibition) but not rolling or adhesion. As found before, TNF-α–induced leukocyte transmigration was unaltered in the KO mice. WT mice treated with the anti–ICAM-2 mAb also exhibited a selective reduction in leukocyte transmigration in response to IL-1β while an anti–ICAM-1 mAb inhibited both leukocyte adhesion and transmigration. Interestingly, mAb 3C4 significantly suppressed IL-1β–induced neutrophil transmigration in PE-CAM-1 KO animals in the peritonitis model but not in the cremaster muscle. The findings provide direct evidence for the involvement of ICAM-2 in neutrophil transmigration in vivo, though this role appears to be stimulus specific. Furthermore, ICAM-2 appears capable of mediating PECAM-1–independent leukocyte transmigration.

scholarly journals BTK Inhibition Reverses MDSC-Mediated Immunosuppression and Enhances Response to Anti-PDL1 Therapy in Neuroblastoma

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 817
Author(s):  
Mehreen Ishfaq ◽  
Timothy Pham ◽  
Cooper Beaman ◽  
Pablo Tamayo ◽  
Alice L. Yu ◽  
...  
Keyword(s):  
T Cell ◽  
Tumor Growth ◽  
Checkpoint Inhibitors ◽  
No Production ◽  
Free Survival ◽  
T Cell Infiltration ◽  
Car T ◽  
Checkpoint Inhibitor Therapy

MDSCs are immune cells of myeloid lineage that plays a key role in promoting tumor growth. The expansion of MDSCs in tumor-bearing hosts reduces the efficacy of checkpoint inhibitors and CAR-T therapies, and hence strategies that deplete or block the recruitment of MDSCs have shown benefit in improving responses to immunotherapy in various cancers, including NB. Ibrutinib, an irreversible molecular inhibitor of BTK, has been widely studied in B cell malignancies, and recently, this drug is repurposed for the treatment of solid tumors. Herein we report that BTK is highly expressed in both granulocytic and monocytic murine MDSCs isolated from mice bearing NB tumors, and its increased expression correlates with a poor relapse-free survival probability of NB patients. Moreover, in vitro treatment of murine MDSCs with ibrutinib altered NO production, decreased mRNA expression of Ido, Arg, Tgfβ, and displayed defects in T-cell suppression. Consistent with these findings, in vivo inhibition of BTK with ibrutinib resulted in reduced MDSC-mediated immune suppression, increased CD8+ T cell infiltration, decreased tumor growth, and improved response to anti-PDL1 checkpoint inhibitor therapy in a murine model of NB. These results demonstrate that ibrutinib modulates immunosuppressive functions of MDSC and can be used either alone or in combination with immunotherapy for augmenting antitumor immune responses in NB.

scholarly journals Effects of chitosan on nitric oxide production and inducible nitric oxide synthase activity and mRNA expression in weaned piglets

2018 ◽  
Vol 60 (No. 8) ◽  
pp. 359-366
Author(s):  
J. Li ◽  
B. Shi ◽  
S. Yan ◽  
L. Jin ◽  
Y. Guo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Mrna Expression ◽  
Inducible Nitric Oxide Synthase ◽  
No Production ◽  
Weaned Piglets ◽  
Inos Activity ◽  
Oxide Synthase ◽  
Inducible Nitric Oxide

The effects of chitosan on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity and gene expression in vivo or vitro were investigated in weaned piglets. In vivo, 180 weaned piglets were assigned to five dietary treatments with six replicates. The piglets were fed on a basal diet supplemented with 0 (control), 100, 500, 1000, and 2000 mg chitosan/kg feed, respectively. In vitro, the peripheral blood mononuclear cells (PBMCs) from a weaned piglet were cultured respectively with 0 (control), 40, 80, 160, and 320 µg chitosan/ml medium. Results showed that serum NO concentrations on days 14 and 28 and iNOS activity on day 28 were quadratically improved with increasing chitosan dose (P < 0.05). The iNOS mRNA expressions were linearly or quadratically enhanced in the duodenum on day 28, and were improved quadratically in the jejunum on days 14 and 28 and in the ileum on day 28 (P < 0.01). In vitro, the NO concentrations, iNOS activity, and mRNA expression in unstimulated PBMCs were quadratically enhanced by chitosan, but the improvement of NO concentrations and iNOS activity by chitosan were markedly inhibited by N-(3-[aminomethyl] benzyl) acetamidine (1400w) (P < 0.05). Moreover, the increase of NO concentrations, iNOS activity, and mRNA expression in PBMCs induced by lipopolysaccharide (LPS) were suppressed significantly by chitosan (P < 0.05). The results indicated that the NO concentrations, iNOS activity, and mRNA expression in piglets were increased by feeding chitosan in a dose-dependent manner. In addition, chitosan improved the NO production in unstimulated PBMCs but inhibited its production in LPS-induced cells, which exerted bidirectional regulatory effects on the NO production via modulated iNOS activity and mRNA expression.

A novel vasculo-angiogenic effect of cilostazol mediated by cross-talk between multiple signalling pathways including the ERK/p38 MAPK signalling transduction cascade

2012 ◽  
Vol 123 (3) ◽  
pp. 147-159 ◽  
Author(s):  
Ting-Hsing Chao ◽  
Shih-Ya Tseng ◽  
Yi-Heng Li ◽  
Ping-Yen Liu ◽  
Chung-Lung Cho ◽  
...  
Keyword(s):  
Protein Kinase ◽  
P38 Mapk ◽  
Umbilical Vein ◽  
Tube Formation ◽  
Mitogen Activated Protein Kinase ◽  
Signalling Pathways ◽  
No Production ◽  
Angiogenic Effect

Cilostazol is an anti-platelet agent with vasodilatory activity that acts by increasing intracellular concentrations of cAMP. Recent reports have suggested that cilostazol may promote angiogenesis. In the present study, we have investigated the effect of cilostazol in promoting angiogenesis and vasculogenesis in a hindlimb ischaemia model and have also examined its potential mechanism of action in vitro and in vivo. We found that cilostazol treatment significantly increased colony formation by human early EPCs (endothelial progenitor cells) through a mechanism involving the activation of cAMP/PKA (protein kinase A), PI3K (phosphoinositide 3-kinase)/Akt/eNOS (endothelial NO synthase) and ERK (extracellular-signal-regulated kinase)/p38 MAPK (mitogen-activated protein kinase) signalling pathways. Cilostazol also enhanced proliferation, chemotaxis, NO production and vascular tube formation in HUVECs (human umbilical vein endothelial cells) through activation of multiple signalling pathways downstream of PI3K/Akt/eNOS. Cilostazol up-regulated VEGF (vascular endothelial growth factor)-A165 expression and secretion of VEGF-A in HUVECs through activation of the PI3K/Akt/eNOS pathway. In a mouse hindlimb ischaemia model, recovery of blood flow ratio (ipsilateral/contralateral) 14 days after surgery was significantly improved in cilostazol-treated mice (10 mg/kg of body weight) compared with vehicle-treated controls (0.63±0.07 and 0.43±0.05 respectively, P<0.05). Circulating CD34+ cells were also increased in cilostazol-treated mice (3614±670 compared with 2151±608 cells/ml, P<0.05). Expression of VEGF and phosphorylation of PI3K/Akt/eNOS and ERK/p38 MAPK in ischaemic muscles were significantly enhanced by cilostazol. Our data suggest that cilostazol produces a vasculo-angiogenic effect by up-regulating a broad signalling network that includes the ERK/p38 MAPK, VEGF-A165, PI3K/Akt/eNOS and cAMP/PKA pathways.

Abstract 12231: PECAM1 is Essential for Flow-mediated Gab1 Tyrosine Phosphorylation and Signaling in vitro and in vivo

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
Suowen Xu ◽  
Marina Koroleva ◽  
Keigi Fujiwara ◽  
Zheng Gen Jin
Keyword(s):  
Tyrosine Phosphorylation ◽  
Wheel Running ◽  
Tyrosine Phosphatase ◽  
Common Mechanism ◽  
Membrane Localization ◽  
No Production ◽  
Voluntary Wheel Running ◽  
Voluntary Wheel

Introduction: Impaired activation of endothelial nitric oxide (NO) synthase (eNOS) and ensued NO production is a common mechanism of various cardiovascular pathologies, including hypertension and atherosclerosis. Specific signaling cascades, generated by vascular endothelial cells (ECs) in response to laminar flow, modulate EC structure and functions, NO production in particular. We have previously shown that flow-stimulated Gab1 (Grb2-associated binder-1) tyrosine phosphorylation mediates eNOS activation. However, the upstream mechanism that regulates Gab1 tyrosine phosphorylation remains unclear. Hypothesis: We hypothesized that platelet endothelial cell adhesion molecule-1 (PECAM1), a key molecule in an endothelial mechanosensing complex, specifically mediates Gab1 tyrosine phosphorylation and its downstream Akt and eNOS activation in ECs upon flow rather than hepatocyte growth factor (HGF) stimulation. Methods: Western blot, en face staining and voluntary wheel running. Results: Small interfering RNA (siRNA) targeting PECAM1 abolished flow- but not HGF-induced Gab1 tyrosine phosphorylation and Akt, eNOS activation as well as Gab1 membrane translocation. Protein-tyrosine phosphatase SHP2, which has been shown to interact with Gab1, was involved in a flow signaling pathway as well as HGF-induced signaling, as SHP2 siRNA diminished the flow- and HGF-induced Gab1 tyrosine phosphorylation, membrane localization and downstream signaling. Pharmacological inhibition of PI3K by LY294002 decreased flow, but not HGF-mediated Gab1 phosphorylation and membrane localization as well as eNOS activation. Finally, we observed that flow-mediated Gab1 and eNOS phosphorylation in vivo induced by voluntary wheel running was reduced in PECAM1 knockout mice. Conclusions: These results demonstrate a specific role of PECAM1 in flow-mediated Gab1 tyrosine phosphorylation and eNOS signaling in ECs

scholarly journals Effects of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans on phagocytic response of Eisenia andrei coelomocytes

2011 ◽  
Vol 1 (1) ◽  
pp. 6 ◽  
Author(s):  
Hayet Belmeskine ◽  
Pauline Brousseau ◽  
Sami Haddad ◽  
Louise Vandelac ◽  
Michel Fournier
Keyword(s):  
Flow Cytometry ◽  
Phagocytic Activity ◽  
Cytotoxic Effect ◽  
Polychlorinated Dibenzofurans ◽  
Eisenia Andrei ◽  
Phagocytic Capacity ◽  
Excessive Secretion ◽  
Phagocytic Response

The immunotoxicological effects of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) mixtures on <em>Eisenia andrei </em>earthworms have never been studied. In this work we investigated these effects both for <em>in vitro </em>and <em>in vivo</em> exposure, using the viability and the phagocytic activity of coelomocytes as immunological biomarkers and the flow cytometry was used for analysis. The <em>in vitro </em>exposure revealed a cytotoxic effect of PCDD/Fs mixture (C2) containing 50&yen;10-3 ng/mL of 2, 3, 7, 8-TCDD and an induction of the phagocytic capacity at the mixture (C1) containing 25&yen;10-3 ng/mL of 2, 3, 7, 8-TCDD. In the <em>in vivo </em>filter paper exposure, the immunocompetence of earthworms was assessed after 3 h-exposure to mixtures of PCDD/Fs at the levels of C1, C2, C3 and C4 containing about; 0.05, 0.3, 0.5 and 0.83 ng of 2, 3, 7, 8-TCDD/cm&sup2;, respectively. Morphological observations showed an excessive secretion of mucus and body surface lesions in worms exposed to higher concentrations (C3 and C4), which revealed that these organisms were affected by PCDD/Fs either through skin and/or by feeding. The levels of the extruded cell yield decreased significantly at all the concentrations tested. However, the cell viability was shown to be unaffected by PCDD/Fs concentrations. It was also shown, that exposure to the highest PCDD/Fs concentrations; C2, C3 and C4 inhibited both phagocytic activity and efficiency.

scholarly journals Assessment of phagocytic activity in live macrophages-tumor cells co-cultures by Confocal and Nomarski Microscopy

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Dalia Martinez-Marin ◽  
Courtney Jarvis ◽  
Thomas Nelius ◽  
Stéphanie Filleur
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Phagocytic Activity ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Functional Assay ◽  
Loss Of Function ◽  
Multiple Cancer

Abstract Macrophages have been recognized as the main inflammatory component of the tumor microenvironment. Although often considered as beneficial for tumor growth and disease progression, tumor-associated macrophages have also been shown to be detrimental to the tumor depending on the tumor microenvironment. Therefore, understanding the molecular interactions between macrophages and tumor cells in relation to macrophages functional activities such as phagocytosis is critical for a better comprehension of their tumor-modulating action. Still, the characterization of these molecular mechanisms in vivo remains complicated due to the extraordinary complexity of the tumor microenvironment and the broad range of tumor-associated macrophage functions. Thus, there is an increasing demand for in vitro methodologies to study the role of cell–cell interactions in the tumor microenvironment. In the present study, we have developed live co-cultures of macrophages and human prostate tumor cells to assess the phagocytic activity of macrophages using a combination of Confocal and Nomarski Microscopy. Using this model, we have emphasized that this is a sensitive, measurable, and highly reproducible functional assay. We have also highlighted that this assay can be applied to multiple cancer cell types and used as a selection tool for a variety of different types of phagocytosis agonists. Finally, combining with other studies such as gain/loss of function or signaling studies remains possible. A better understanding of the interactions between tumor cells and macrophages may lead to the identification of new therapeutic targets against cancer.

scholarly journals In Vitro Study of Nitric Oxide Metabolites Effects on Human Hydatid ofEchinococcus granulosus

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
Razika Zeghir-Bouteldja ◽  
Manel Amri ◽  
Saliha Aitaissa ◽  
Samia Bouaziz ◽  
Dalila Mezioug ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Hydatid Cyst ◽  
Echinococcus Granulosus ◽  
In Vitro Study ◽  
No Production ◽  
In Vitro Effects ◽  
Nitric Oxide Metabolites

Hydatidosis is characterized by the long-term coexistence of larvaEchinococcus granulosusand its host without effective rejection. Previous studies demonstrated nitric oxide (NO) production (in vivo and in vitro) during hydatidosis. In this study, we investigated the direct in vitro effects of NO species: nitrite (NO2−), nitrate (NO3−) and peroxynitrite (ONOO−) on protoscolices (PSCs) viability and hydatid cyst layers integrity for 24 hours and 48 hours. Our results showed protoscolicidal activity ofNO2−andONOO−24 hours and 3 hours after treatment with 320 μM and 80 μM respectively. Degenerative effects were observed on germinal and laminated layers. The comparison of the in vitro effects of NO species on the PSCs viability indicated thatONOO−is more cytotoxic thanNO2−. In contrast,NO3−has no effect. These results suggest possible involvement ofNO2−andONOO−in antihydatic action and point the efficacy of these metabolites as scolicidal agents.

scholarly journals A CRISPR/Cas9 vector system for neutrophil-specific gene disruption in zebrafish

2020 ◽  
Author(s):  
Yueyang Wang ◽  
Alan Y. Hsu ◽  
Eric M. Walton ◽  
Ramizah Syahirah ◽  
Tianqi Wang ◽  
...  
Keyword(s):  
Cell Motility ◽  
Neutrophil Migration ◽  
Transgenic Fish ◽  
Subcellular Location ◽  
Vector System ◽  
Specific Gene ◽  
Tissue Specific ◽  
Biological Studies

AbstractTissue-specific knockout techniques are widely applied in biological studies to probe the tissue-specific roles of specific genes in physiology, development, and disease. CRISPR/Cas9 is a widely used technology to perform fast and efficient genome editing in vitro and in vivo. Here, we report a robust CRISPR-based gateway system for tissue-specific gene inactivation in zebrafish. A transgenic fish line expressing Cas9 under the control of a neutrophil-restricted promoter was constructed. As proof of principle, we transiently disrupted rac2 or cdk2 in neutrophils using plasmids driving the expression of sgRNAs from U6 promoters. Loss of the rac2 or cdk2 gene in neutrophils resulted in significantly decreased cell motility, which could be restored by re-expressing Rac2 or Cdk2 in neutrophils in the corresponding knockout background. The subcellular location of Rac activation and actin structure and stress in the context of neutrophil migration was determined in both the wild-type and rac2 knockout neutrophils in vivo. In addition, we evaluated an alternative approach where the Cas9 protein is ubiquitously expressed while the sgRNA is processed by ribozymes and expressed in a neutrophil-restricted manner. Cell motility was also reduced upon rac2 sgRNA expression. Together, our work provides a potent tool that can be used to advance the utility of zebrafish in identification and characterization of gene functions in neutrophils.

scholarly journals Hexarelin exerts neuroprotective and antioxidant effects against hydrogen peroxide-induced toxicity through the modulation of MAPK and PI3K/Akt patways in Neuro-2A cells

2020 ◽  
Author(s):  
Ramona Meanti ◽  
Laura Rizzi ◽  
Elena Bresciani ◽  
Laura Molteni ◽  
Vittorio Locatelli ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Apoptotic Cell ◽  
Neuroblastoma Cell ◽  
Neuroblastoma Cell Line ◽  
Inhibitory Influence ◽  
No Production ◽  
Mrna Levels

AbstractHexarelin, a synthetic hexapeptide, protects cardiac and skeletal muscles by inhibiting apoptosis, both in vitro and in vivo. Moreover, evidence suggests that hexarelin could have important neuroprotective bioactivity.Oxidative stress and the generation of free radicals has been implicated in the etiologies of several neurodegenerative diseases, including amyotrophic lateral sclerosis, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and multiple sclerosis. In addition to direct oxidative stress, exogenous hydrogen peroxide (H2O2) can penetrate biological membranes and enhance the formation of other reactive oxygen species.The aim of this study was to examine the inhibitory influence of hexarelin on H2O2-induced apoptosis in Neuro-2A cells, a mouse neuroblastoma cell line. Our results indicate that H2O2 reduced the viability of Neuro-2A cells in a dose-related fashion. Furthermore, H2O2 induced significant changes in the morphology of Neuro-2A cells, reflected in the formation of apoptotic cell bodies, and an increase of nitric oxide (NO) production. Hexarelin effectively antagonized H2O2 oxidative damage to Neuro-2A cells as indicated by improved cell viability, normal morphology and reduced nitrite (NO2−) release. Hexarelin treatment of Neuro-2A cells also reduced mRNA levels of caspases−3 and −7 and those of the pro-apoptotic molecule Bax; by contrast, hexarelin treatment increased anti-apoptotic Bcl-2 mRNA levels. Hexarelin also reduced MAPKs phosphorylation induced by H2O2 and concurrently increased p-Akt protein expression.In conclusion, our results identify several neuroprotective and anti-apoptotic effects of hexarelin. These properties suggest that further investigation of hexarelin as a neuroprotective agent in an investigational and therapeutic context are merited.

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