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  1. Dexamethasone palmitate ameliorates macrophages-rich graft-versus-host disease by inhibiting macrophage functions.

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    Satoshi Nishiwaki

    Full Text Available Macrophage infiltration of skin GVHD lesions correlates directly with disease severity, but the mechanisms underlying this relationship remain unclear and GVHD with many macrophages is a therapeutic challenge. Here, we characterize the macrophages involved in GVHD and report that dexamethasone palmitate (DP, a liposteroid, can ameliorate such GVHD by inhibiting macrophage functions. We found that host-derived macrophages could exacerbate GVHD in a mouse model through expression of higher levels of pro-inflammatory TNF-α and IFN-γ, and lower levels of anti-inflammatory IL-10 than resident macrophages in mice without GVHD. DP significantly decreased the viability and migration capacity of primary mouse macrophages compared to conventional dexamethasone in vitro. DP treatment on day 7 and day 14 decreased macrophage number, and attenuated GVHD score and subsequent mortality in a murine model. This is the first study to provide evidence that therapy for GVHD should be changed on the basis of infiltrating cell type.

  2. Pirfenidone inhibits macrophage infiltration in 5/6 nephrectomized rats.

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    Chen, Jun-Feng; Ni, Hai-Feng; Pan, Ming-Ming; Liu, Hong; Xu, Min; Zhang, Ming-Hui; Liu, Bi-Cheng

    2013-03-15

    Tubulointerstitial macrophage infiltration is a hallmark of chronic kidney disease involved in the progression of renal fibrosis. Pirfenidone is a newly identified antifibrotic drug, the potential mechanism of which remains unclear. The aim of this study was to investigate the effects of pirfenidone on M1/M2 macrophage infiltration in nephrectomized rats. Nephrectomized rats were treated with pirfenidone by gavage for 12 wk. Twenty-four hour urinary protein, N-acetyl-β-D-glycosaminidase (NAG) activity, systolic blood pressure, and C-reactive protein were determined. Paraffin-embedded sections were stained for CD68, CCR7, and CD163 macrophages. Monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α), as well as M1 and M2 macrophages secretory markers, were evaluated by real-time RT-PCR and Western blotting analysis. Pirfenidone significantly improved the elevated proteinuria and NAG activity from week 2 onward after surgery. Pirfenidone attenuated interstitial fibrosis and decreased expression of fibrotic markers including transforming growth factor-β(1), connective tissue growth factor, α-smooth muscle actin, fibronectin, and fibroblast-specific protein-1. Pirfenidone significantly decreased the infiltrating macrophages. The number of M1 and M2 macrophages was significantly lower after pirfenidone treatment. MCP-1 and MIP-1α were increased in nephrectomized rats at mRNA and protein levels. Pirfenidone treatment significantly inhibited their expression. The TNF-α, IL-6, and nitric oxide synthases-2 expressed by M1 macrophages were increased in nephrectomized rats, and pirfenidone significantly attenuated their expression. Pirfenidone treatment also significantly decreased arginase-1, dectin-1, CD206, and CD86 expressed by M2 macrophages. Thus pirfenidone inhibits M1 and M2 macrophage infiltration in 5/6 nephrectomized rats, which suggests its efficacy in the early and late periods of renal fibrosis.

  3. Ginger extract inhibits LPS induced macrophage activation and function

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    Bruch David

    2008-01-01

    Full Text Available Abstract Background Macrophages play a dual role in host defence. They act as the first line of defence by mounting an inflammatory response to antigen exposure and also act as antigen presenting cells and initiate the adaptive immune response. They are also the primary infiltrating cells at the site of inflammation. Inhibition of macrophage activation is one of the possible approaches towards modulating inflammation. Both conventional and alternative approaches are being studied in this regard. Ginger, an herbal product with broad anti inflammatory actions, is used as an alternative medicine in a number of inflammatory conditions like rheumatic disorders. In the present study we examined the effect of ginger extract on macrophage activation in the presence of LPS stimulation. Methods Murine peritoneal macrophages were stimulated by LPS in presence or absence of ginger extract and production of proinflammatory cytokines and chemokines were observed. We also studied the effect of ginger extract on the LPS induced expression of MHC II, B7.1, B7.2 and CD40 molecules. We also studied the antigen presenting function of ginger extract treated macrophages by primary mixed lymphocyte reaction. Results We observed that ginger extract inhibited IL-12, TNF-α, IL-1β (pro inflammatory cytokines and RANTES, MCP-1 (pro inflammatory chemokines production in LPS stimulated macrophages. Ginger extract also down regulated the expression of B7.1, B7.2 and MHC class II molecules. In addition ginger extract negatively affected the antigen presenting function of macrophages and we observed a significant reduction in T cell proliferation in response to allostimulation, when ginger extract treated macrophages were used as APCs. A significant decrease in IFN-γ and IL-2 production by T cells in response to allostimulation was also observed. Conclusion In conclusion ginger extract inhibits macrophage activation and APC function and indirectly inhibits T cell activation.

  4. Consistent inhibition of cyclooxygenase drives macrophages towards the inflammatory phenotype.

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    Yi Rang Na

    Full Text Available Macrophages play important roles in defense against infection, as well as in homeostasis maintenance. Thus alterations of macrophage function can have unexpected pathological results. Cyclooxygenase (COX inhibitors are widely used to relieve pain, but the effects of long-term usage on macrophage function remain to be elucidated. Using bone marrow-derived macrophage culture and long-term COX inhibitor treatments in BALB/c mice and zebrafish, we showed that chronic COX inhibition drives macrophages into an inflammatory state. Macrophages differentiated in the presence of SC-560 (COX-1 inhibitor, NS-398 (COX-2 inhibitor or indomethacin (COX-1/2 inhibitor for 7 days produced more TNFα or IL-12p70 with enhanced p65/IκB phosphoylation. YmI and IRF4 expression was reduced significantly, indicative of a more inflammatory phenotype. We further observed that indomethacin or NS-398 delivery accelerated zebrafish death rates during LPS induced sepsis. When COX inhibitors were released over 30 days from an osmotic pump implant in mice, macrophages from peritoneal cavities and adipose tissue produced more TNFα in both the basal state and under LPS stimulation. Consequently, indomethacin-exposed mice showed accelerated systemic inflammation after LPS injection. Our findings suggest that macrophages exhibit a more inflammatory phenotype when COX activities are chronically inhibited.

  5. Inhibition of 5-Lipoxygenase Pathway Attenuates Acute Liver Failure by Inhibiting Macrophage Activation

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    Lu Li

    2014-01-01

    Full Text Available This study aimed to investigate the role of 5-lipoxygenase (5-LO in acute liver failure (ALF and changes in macrophage activation by blocking it. ALF was induced in rats by administration of D-galactosamine (D-GalN/lipopolysaccharide (LPS. Rats were injected intraperitoneally with AA-861 (a specific 5-LO inhibitor, 24 hr before D-GalN/LPS administration. After D-GalN/LPS injection, the liver tissue was collected for assessment of histology, macrophage microstructure, macrophage counts, 5-LO mRNA formation, protein expression, and concentration of leukotrienes. Serum was collected for detecting alanine aminotransferase (ALT, aspartate transaminase (AST, total bilirubin (Tbil, and tumor necrosis factor- (TNF-α. Twenty-four hours after injection, compared with controls, ALF rats were characterized by widespread hepatocyte necrosis and elevated ALT, AST, and Tbil, and 5-LO protein expression reached a peak. Liver leukotriene B4 was also significantly elevated. However, 5-LO mRNA reached a peak 8 hr after D-GalN/LPS injection. Simultaneously, the microstructure of macrophages was changed most significantly and macrophages counts were increased significantly. Moreover, serum TNF-α was also elevated. By contrast, AA-861 pretreatment significantly decreased liver necrosis as well as all of the parameters compared with the rats without pretreatment. Macrophages, via the 5-LO pathway, play a critical role in ALF, and 5-LO inhibitor significantly alleviates ALF, possibly related to macrophage inhibition.

  6. Paeoniflorin inhibits macrophage-mediated lung cancer metastasis.

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    Wu, Qi; Chen, Gang-Ling; Li, Ya-Juan; Chen, Yang; Lin, Fang-Zhen

    2015-12-01

    Alternatively activated macrophages are more frequently involved in tumor growth, angiogenesis, and immunosuppression. A previous study showed that paeoniflorin, the major active constituent of Paeonia lactiflora Pallas, can inhibit tumor growth and lung metastases of Lewis lung tumor-bearing mice. This study tried to investigate whether paeoniflorin inhibited lung cancer metastasis by inhibiting the alternative activation of macrophages (M2 macrophage). Using a viability assay, the cytotoxicity of paeoniflorin on Lewis lung cancer cells and peritoneal macrophages were investigated. In vitro scratch wound and in vivo lung metastasis experiments were used to test the ability to inhibit the migration of paeoniflorin and the function of M2 macrophages. Flow cytometry was performed to test the cell cycle of Lewis lung cancer cells, and to test the M2 macrophages in peritoneal macrophages and subcutaneous transplantable tumor. It was found that paeoniflorin showed no inhibitory effect on the growth of Lewis lung cancer cells and peritoneal macrophages of mouse in vitro. Paeoniflorin could attenuate the migration of LLC stimulated by alternatively activated macrophages (stimulated for 24 h and 48 h, paeoniflorin 1, 3, 10, 30, 100 μmol·L(-1), P lung cancer cells (paeoniflorin 100 μmol·L(-1), P lung metastasis of Lewis lung cancer cells xenograft and decrease the numbers of M2 macrophages in subcutaneous xenograft tumour in vivo (paeoniflorin 20, 40 mg·kg(-1), P lung metastasis of Lewis lung cancer cells xenograft partly through inhibiting the alternative activation of macrophages.

  7. Amlodipine inhibits matrix metalloproteinases expression and secretion in mouse macrophage

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    Yamin CAO; Shiwen WANG; Haiyun WU

    2005-01-01

    To investigate whether the calcium channel blocker amlodipine could inhibit macrophage matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) expression and secretion. Methods Peritoneal macrophages were isolated from BALB/C mice and incubated with low (5μg/L), middle (15μg/L) and high (305μg/L) concentrations of amlodipine, or in the medium alone (controls) for 24 hours, and the expression and secretion of MMP-2 and MM-9 of the cells were analyzed by RT-PCR and gelatin zymography. Results Compared with controls, amlodipine at low concentration had no significant effects on the expression and secretion of either MMP-2 and MMP-9 (P>0.05);at middle concentrationit it could inhibited MMP-2 and MMP-9 expressions completely and significantly reduced the secretion of MMP-9 (P<0.05); but it had no effect on the secretion of MMP-2. At high concentration it also inhibited MMP-2 and MMP-9 expression completely. Conclusion Amlodipine at 15 ìg/L inhibited the expression of MMP-2 and MMP-9 and reduced the secretion of MMP-9, suggesting that amlodipine may stabilize atherosclerotic plaque.

  8. Cyclooxygenase-2 inhibition blocks M2 macrophage differentiation and suppresses metastasis in murine breast cancer model.

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    Yi-Rang Na

    Full Text Available Tumor cells are often associated with abundant macrophages that resemble the alternatively activated M2 subset. Tumor-associated macrophages (TAMs inhibit anti-tumor immune responses and promote metastasis. Cyclooxygenase-2 (COX-2 inhibition is known to prevent breast cancer metastasis. This study hypothesized that COX-2 inhibition affects TAM characteristics potentially relevant to tumor cell metastasis. We found that the specific COX-2 inhibitor, etodolac, inhibited human M2 macrophage differentiation, as determined by decreased CD14 and CD163 expressions and increased TNFα production. Several key metastasis-related mediators, such as vascular endothelial growth factor-A, vascular endothelial growth factor-C, and matrix metalloproteinase-9, were inhibited in the presence of etodolac as compared to untreated M2 macrophages. Murine bone marrow derived M2 macrophages also showed enhanced surface MHCII IA/IE and CD80, CD86 expressions together with enhanced TNFα expressions with etodolac treatment during differentiation. Using a BALB/c breast cancer model, we found that etodolac significantly reduced lung metastasis, possibly due to macrophages expressing increased IA/IE and TNFα, but decreased M2 macrophage-related genes expressions (Ym1, TGFβ. In conclusion, COX-2 inhibition caused loss of the M2 macrophage characteristics of TAMs and may assist prevention of breast cancer metastasis.

  9. Kaurane diterpenes protect against apoptosis and inhibition of phagocytosis in activated macrophages.

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    de las Heras, B; Hortelano, S; Girón, N; Bermejo, P; Rodríguez, B; Boscá, L

    2007-09-01

    The kaurane diterpenes foliol and linearol are inhibitors of the activation of nuclear factor kappaB, a transcription factor involved in the inflammatory response. Effects of these diterpenes on apoptosis and phagocytosis have been analysed in cultured peritoneal macrophages and in the mouse macrophage cell line, RAW 264.7. Macrophages were maintained in culture and activated with pro-inflammatory stimuli in the absence or presence of diterpenes. Apoptosis and the phagocytosis in these cells under these conditions were determined. Incubation of macrophages with a mixture of bacterial lipopolysaccharide (LPS)/interferon-gamma (IFN-gamma) induced apoptosis through a NO-dependent pathway, an effect significantly inhibited by foliol and linearol in the low muM range, without cytotoxic effects. Apoptosis in macrophages induced by NO donors was also inhibited. The diterpenes prevented apoptosis through a mechanism compatible with the inhibition of caspase-3 activation, release of cytochrome c to the cytosol and p53 overexpression, as well as an alteration in the levels of proteins of the Bcl-2 family, in particular, the levels of Bax. Cleavage of poly(ADP-ribose) polymerase, a well-established caspase substrate, was reduced by these diterpenes. Treatment of cells with foliol and linearol decreased phagocytosis of zymosan bioparticles by RAW 264.7 cells and to a greater extent by peritoneal macrophages. Both diterpenes protected macrophages from apoptosis and inhibited phagocytosis, resulting in a paradoxical control of macrophage function, as viability was prolonged but inflammatory and phagocytic functions were impaired.

  10. [Significance of macrophage and cytokines in expression of stone matrix].

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    Ito, T

    1996-05-01

    (BACKGROUND). Urinary calculus consists of inorganic substances as a major component and organic substances as a minor component. In this study, the organic substances playing an important role in the formation of calculus, such as osteopontin, calprotectin, macrophage and cytokines, are investigated for their significance in the calculus formation mechanism. (METHODS). Using renal tissues of rats having intraperitoneal glyoxylic acid-induced calculus, mode of the expression of osteopontin was examined by in situ hybridization method, immunohistological staining and northern blot method. Then human renal tissues obtained from the nephrectomy specimen conducted for a renal calculus were subjected to immunohistological staining by an enzyme antibody method using antibodies against osteopontin, calprotectin, macrophage and cytokines. (RESULTS). In rats, while the expression of osteopontin mRNA was observed in renal distal tubular cells, no expression was observed in glomerulus or renal interstitial tissues. The level of osteopontin mRNA expression in calculus forming rats was higher than in control rats by northern blot method. In human tissues, all of osteopontin, calprotectin, macrophage exhibited positive results in the renal distal tubular cells and in the calculus nucleus in the renal distal tubular cavity. Calprotectin and macrophage exhibited positive result also in the renal interstitial tissues. Cytokines exhibited positive results for interleukin-1,6, tumor necrosis factor alpha and transforming growth factor beta. Cytokines exhibited positive results in the distal tubular cells. Negative results were observed for interleukin-2,4 and 5. (CONCLUSION). Based on the findings described above, it is concluded that accumulation of macrophage in the renal interstitial tissues takes place and then one type of cytokines sensitive to macrophage is secreted. Subsequently, in the renal distal tubular cells stimulated with macrophage and cytokines, the expression of

  11. Inhibition of mouse peritoneal macrophage DNA synthesis by infection with the Arenavirus Pichinde. Interim report

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    Friedlander, A.M.; Jahrling, P.B.; Merrill, P.; Tobery, S.

    1983-01-19

    Macrophage DNA synthesis and proliferation occur during the development of cell-mediated immunity and in the early non-specific reaction to infection. Arenaviruses have a predilection for infection of cells of the reticuloendothelial system and in this study we have examined the effect of the arenavirus Pichinde on macrophage DNA synthesis. We have found that infection of mouse peritoneal macrophages with Pichinde caused a profound dose dependent inhibition of the DNA synthesis induced by macrophage growth factor/colony stimulating factor. At a multiplicity of inoculum of five there is a 75-95% inhibition of DNA synthesis. Viable virus is necessary for inhibition since Pichinde inactivated by heat or cobalt irradiation had no effect. Similarly, virus pre-treated with an antiserum to Pichinde was without inhibitory effect. Inhibition was demonstrated by measuring DNA synthesis spectrofluorometrically as well as by 3H-thymidine incorporation. The inhibition of DNA synthesis was not associated with any cytopathology. There was no evidence that the inhibition was due to soluble factors, such as prostaglandins or interferon, released by infected cells. These studies demonstrate, for the first time in vitro, a significant alteration in macrophage function caused by infection with an arenavirus. It is possible that inhibition of macrophage proliferation represents a mechanism by which some microorganisms interfere with host resistance.

  12. Proprotein convertase 1/3 inhibited macrophages: A novel therapeutic based on drone macrophages

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    Marie Duhamel

    2016-06-01

    Full Text Available We demonstrated here thanks to proteomic, that proprotein convertase 1/3 knockdown macrophages present all the characteristic of activated pro-inflammatory macrophages. TLR4 and TLR9 signaling pathways can be enhanced leading to the secretion of pro-inflammatory factors and antitumor factors. We can control their activation by controlling one enzyme, PC1/3. In a tumor context, PC1/3 inhibition in macrophages may reactivate them and lead to a cytokine storm after stimulation “at distance” with a TLR ligand. Therefore, we name these proprotein convertase inhibited macrophages the “drone macrophages”. They constitute an innovative cell therapy to treat efficiently tumors.

  13. Macrophages and lymphocytes differentially modulate the ability of RANTES to inhibit HIV-1 infection.

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    Gross, Eleanore; Amella, Carol A; Pompucci, Lorena; Franchin, Giovanni; Sherry, Barbara; Schmidtmayerova, Helena

    2003-11-01

    The beta-chemokines MIP-1alpha, MIP-1beta, and RANTES inhibit HIV-1 infection of CD4+ T cells by inhibiting interactions between the virus and CCR5 receptors. However, while beta-chemokine-mediated inhibition of HIV-1 infection of primary lymphocytes is well documented, conflicting results have been obtained using primary macrophages as the virus target. Here, we show that the beta-chemokine RANTES inhibits virus entry into both cellular targets of the virus, lymphocytes and macrophages. However, while virus entry is inhibited at the moment of infection in both cell types, the amount of virus progeny is lowered only in lymphocytes. In macrophages, early-entry restriction is lost during long-term cultivation, and the amount of virus produced by RANTES-treated macrophages is similar to the untreated cultures, suggesting an enhanced virus replication. We further show that at least two distinct cellular responses to RANTES treatment in primary lymphocytes and macrophages contribute to this phenomenon. In lymphocytes, exposure to RANTES significantly increases the pool of inhibitory beta-chemokines through intracellular signals that result in increased production of MIP-1alpha and MIP-1beta, thereby amplifying the antiviral effects of RANTES. In macrophages this amplification step does not occur. In fact, RANTES added to the macrophages is efficiently cleared from the culture, without inducing synthesis of beta-chemokines. Our results demonstrate dichotomous effects of RANTES on HIV-1 entry at the moment of infection, and on production and spread of virus progeny in primary macrophages. Since macrophages serve as a reservoir of HIV-1, this may contribute to the failure of endogenous chemokines to successfully eradicate the virus.

  14. Soybean-derived Bowman-Birk inhibitor inhibits neurotoxicity of LPS-activated macrophages

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    Persidsky Yuri

    2011-02-01

    Full Text Available Abstract Background Lipopolysaccharide (LPS, the major component of the outer membrane of gram-negative bacteria, can activate immune cells including macrophages. Activation of macrophages in the central nervous system (CNS contributes to neuronal injury. Bowman-Birk inhibitor (BBI, a soybean-derived protease inhibitor, has anti-inflammatory properties. In this study, we examined whether BBI has the ability to inhibit LPS-mediated macrophage activation, reducing the release of pro-inflammatory cytokines and subsequent neurotoxicity in primary cortical neural cultures. Methods Mixed cortical neural cultures from rat were used as target cells for testing neurotoxicity induced by LPS-treated macrophage supernatant. Neuronal survival was measured using a cell-based ELISA method for expression of the neuronal marker MAP-2. Intracellular reactive oxygen species (ROS production in macrophages was measured via 2', 7'-dichlorofluorescin diacetate (DCFH2DA oxidation. Cytokine expression was determined by quantitative real-time PCR. Results LPS treatment of macrophages induced expression of proinflammatory cytokines (IL-1β, IL-6 and TNF-α and of ROS. In contrast, BBI pretreatment (1-100 μg/ml of macrophages significantly inhibited LPS-mediated induction of these cytokines and ROS. Further, supernatant from BBI-pretreated and LPS-activated macrophage cultures was found to be less cytotoxic to neurons than that from non-BBI-pretreated and LPS-activated macrophage cultures. BBI, when directly added to the neuronal cultures (1-100 μg/ml, had no protective effect on neurons with or without LPS-activated macrophage supernatant treatment. In addition, BBI (100 μg/ml had no effect on N-methyl-D-aspartic acid (NMDA-mediated neurotoxicity. Conclusions These findings demonstrate that BBI, through its anti-inflammatory properties, protects neurons from neurotoxicity mediated by activated macrophages.

  15. microRNA-150 inhibits the formation of macrophage foam cells through targeting adiponectin receptor 2

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    Li, Jing [Department of Geratory, Linzi District People’s Hospital of Zibo City, Zibo, Shandong (China); Zhang, Suhua, E-mail: drsuhuangzhang@qq.com [Department of HealthCare, Qilu Hospital of Shandong University (Qingdao), Qingdao City, Qingdao (China)

    2016-08-05

    Transformation of macrophages into foam cells plays a critical role in the pathogenesis of atherosclerosis. The aim of this study was to determine the expression and biological roles of microRNA (miR)-150 in the formation of macrophage foam cells and to identify its functional target(s). Exposure to 50 μg/ml oxidized low-density lipoprotein (oxLDL) led to a significant upregulation of miR-150 in THP-1 macrophages. Overexpression of miR-150 inhibited oxLDL-induced lipid accumulation in THP-1 macrophages, while knockdown of miR-150 enhanced lipid accumulation. apoA-I- and HDL-mediated cholesterol efflux was increased by 66% and 43%, respectively, in miR-150-overexpressing macrophages relative to control cells. In contrast, downregulation of miR-150 significantly reduced cholesterol efflux from oxLDL-laden macrophages. Bioinformatic analysis and luciferase reporter assay revealed adiponectin receptor 2 (AdipoR2) as a direct target of miR-150. Small interfering RNA-mediated downregulation of AdipoR2 phenocopied the effects of miR-150 overexpression, reducing lipid accumulation and facilitating cholesterol efflux in oxLDL-treated THP-1 macrophages. Knockdown of AdipoR2 induced the expression of proliferator-activated receptor gamma (PPARγ), liver X receptor alpha (LXRα), ABCA1, and ABCG1. Moreover, pharmacological inhibition of PPARγ or LXRα impaired AdipoR2 silencing-induced upregulation of ABCA1 and ABCG1. Taken together, our results indicate that miR-150 can attenuate oxLDL-induced lipid accumulation in macrophages via promotion of cholesterol efflux. The suppressive effects of miR-150 on macrophage foam cell formation are mediated through targeting of AdipoR2. Delivery of miR-150 may represent a potential approach to prevent macrophage foam cell formation in atherosclerosis. -- Highlights: •miR-150 inhibits macrophage foam cell formation. •miR-150 accelerates cholesterol efflux from oxLDL-laden macrophages. •miR-150 suppresses macrophage foam cell

  16. Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor 5 expression.

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    Wei, Zhiquan; Yan, Li; Chen, Yixin; Bao, Chuanhong; Deng, Jing; Deng, Jiagang

    2016-08-01

    Mangiferin is a natural polyphenol and the predominant effective component of Mangifera indica Linn. leaves. For hundreds of years, Mangifera indica Linn. leaf has been used as an ingredient in numerous traditional Chinese medicine preparations for the treatment of bronchitis. However, the pharmacological mechanism of mangiferin in the treatment of bronchitis remains to be elucidated. Macrophage classical activation is important role in the process of bronchial airway inflammation, and interferon regulatory factor 5 (IRF5) has been identified as a key regulatory factor for macrophage classical activation. The present study used the THP‑1 human monocyte cell line to investigate whether mangiferin inhibits macrophage classical activation via suppressing IRF5 expression in vitro. THP‑1 cells were differentiated to macrophages by phorbol 12‑myristate 13‑acetate. Macrophages were polarized to M1 macrophages following stimulation with lipopolysaccharide (LPS)/interferon‑γ (IFN‑γ). Flow cytometric analysis was conducted to detect the M1 macrophages. Reverse transcription‑quantitative polymerase chain reaction was used to investigate cellular IRF5 gene expression. Levels of proinflammatory cytokines and IRF5 were assessed following cell culture and cellular homogenization using enzyme‑linked immunosorbent assay. IRF5 protein and nuclei co‑localization was performed in macrophages with laser scanning confocal microscope immunofluorescence analysis. The results of the present study demonstrated that mangiferin significantly inhibits LPS/IFN‑γ stimulation‑induced classical activation of macrophages in vitro and markedly decreases proinflammatory cytokine release. In addition, cellular IRF5 expression was markedly downregulated. These results suggest that the inhibitory effect of mangiferin on classical activation of macrophages may be exerted via downregulation of cellular IRF5 expression levels.

  17. Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor 5 expression

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    Wei, Zhiquan; Yan, Li; Chen, Yixin; Bao, Chuanhong; Deng, Jing; Deng, Jiagang

    2016-01-01

    Mangiferin is a natural polyphenol and the predominant effective component of Mangifera indica Linn. leaves. For hundreds of years, Mangifera indica Linn. leaf has been used as an ingredient in numerous traditional Chinese medicine preparations for the treatment of bronchitis. However, the pharmacological mechanism of mangiferin in the treatment of bronchitis remains to be elucidated. Macrophage classical activation is important role in the process of bronchial airway inflammation, and interferon regulatory factor 5 (IRF5) has been identified as a key regulatory factor for macrophage classical activation. The present study used the THP-1 human monocyte cell line to investigate whether mangiferin inhibits macrophage classical activation via suppressing IRF5 expression in vitro. THP-1 cells were differentiated to macrophages by phorbol 12-myristate 13-acetate. Macrophages were polarized to M1 macrophages following stimulation with lipopolysaccharide (LPS)/interferon-γ (IFN-γ). Flow cytometric analysis was conducted to detect the M1 macrophages. Reverse transcription-quantitative polymerase chain reaction was used to investigate cellular IRF5 gene expression. Levels of proinflammatory cytokines and IRF5 were assessed following cell culture and cellular homogenization using enzyme-linked immunosorbent assay. IRF5 protein and nuclei co-localization was performed in macrophages with laser scanning confocal microscope immunofluorescence analysis. The results of the present study demonstrated that mangiferin significantly inhibits LPS/IFN-γ stimulation-induced classical activation of macrophages in vitro and markedly decreases proinflammatory cytokine release. In addition, cellular IRF5 expression was markedly downregulated. These results suggest that the inhibitory effect of mangiferin on classical activation of macrophages may be exerted via downregulation of cellular IRF5 expression levels. PMID:27277156

  18. Chlorogenic acid inhibits glioblastoma growth through repolarizating macrophage from M2 to M1 phenotype

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    Xue, Nina; Zhou, Qin; Ji, Ming; Jin, Jing; Lai, Fangfang; Chen, Ju; Zhang, Mengtian; Jia, Jing; Yang, Huarong; Zhang, Jie; Li, Wenbin; Jiang, Jiandong; Chen, Xiaoguang

    2017-01-01

    Glioblastoma is an aggressive tumor that is associated with distinctive infiltrating microglia/macrophages populations. Previous studies demonstrated that chlorogenic acid (5-caffeoylquinic acid, CHA), a phenolic compound with low molecular weight, has an anti-tumor effect in multiple malignant tumors. In the present study, we focused on the macrophage polarization to investigate the molecular mechanisms behind the anti-glioma response of CHA in vitro and in vivo. We found that CHA treatment increased the expression of M1 markers induced by LPS/IFNγ, including iNOS, MHC II (I-A/I-E subregions) and CD11c, and reduced the expression of M2 markers Arg and CD206 induced by IL-4, resulting in promoting the production of apoptotic-like cancer cells and inhibiting the growth of tumor cells by co-culture experiments. The activations of STAT1 and STAT6, which are two crucial signaling events in M1 and M2-polarization, were significantly promoted and suppressed by CHA in macrophages, respectively. Furthermore, In G422 xenograft mice, CHA increased the proportion of CD11c-positive M1 macrophages and decreased the distribution of CD206-positive M2 macrophages in tumor tissue, consistent with the reduction of tumor weight observed in CHA-treated mice. Overall these findings indicated CHA as a potential therapeutic approach to reduce glioma growth through promoting M1-polarized macrophage and inhibiting M2 phenotypic macrophage. PMID:28045028

  19. Atheroprotection through SYK inhibition fails in established disease when local macrophage proliferation dominates lesion progression.

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    Lindau, Alexandra; Härdtner, Carmen; Hergeth, Sonja P; Blanz, Kelly Daryll; Dufner, Bianca; Hoppe, Natalie; Anto-Michel, Nathaly; Kornemann, Jan; Zou, Jiadai; Gerhardt, Louisa M S; Heidt, Timo; Willecke, Florian; Geis, Serjosha; Stachon, Peter; Wolf, Dennis; Libby, Peter; Swirski, Filip K; Robbins, Clinton S; McPheat, William; Hawley, Shaun; Braddock, Martin; Gilsbach, Ralf; Hein, Lutz; von zur Mühlen, Constantin; Bode, Christoph; Zirlik, Andreas; Hilgendorf, Ingo

    2016-03-01

    Macrophages in the arterial intima sustain chronic inflammation during atherogenesis. Under hypercholesterolemic conditions murine Ly6C(high) monocytes surge in the blood and spleen, infiltrate nascent atherosclerotic plaques, and differentiate into macrophages that proliferate locally as disease progresses. Spleen tyrosine kinase (SYK) may participate in downstream signaling of various receptors that mediate these processes. We tested the effect of the SYK inhibitor fostamatinib on hypercholesterolemia-associated myelopoiesis and plaque formation in Apoe(-/-) mice during early and established atherosclerosis. Mice consuming a high cholesterol diet supplemented with fostamatinib for 8 weeks developed less atherosclerosis. Histologic and flow cytometric analysis of aortic tissue showed that fostamatinib reduced the content of Ly6C(high) monocytes and macrophages. SYK inhibition limited Ly6C(high) monocytosis through interference with GM-CSF/IL-3 stimulated myelopoiesis, attenuated cell adhesion to the intimal surface, and blocked M-CSF stimulated monocyte to macrophage differentiation. In Apoe(-/-) mice with established atherosclerosis, however, fostamatinib treatment did not limit macrophage accumulation or lesion progression despite a significant reduction in blood monocyte counts, as lesional macrophages continued to proliferate. Thus, inhibition of hypercholesterolemia-associated monocytosis, monocyte infiltration, and differentiation by SYK antagonism attenuates early atherogenesis but not established disease when local macrophage proliferation dominates lesion progression.

  20. The 5-lipoxygenase inhibitor, zileuton, suppresses prostaglandin biosynthesis by inhibition of arachidonic acid release in macrophages

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    Rossi, A; Pergola, C; Koeberle, A; Hoffmann, M; Dehm, F; Bramanti, P; Cuzzocrea, S; Werz, O; Sautebin, L

    2010-01-01

    BACKGROUND AND PURPOSE Zileuton is the only 5-lipoxygenase (5-LOX) inhibitor marketed as a treatment for asthma, and is often utilized as a selective tool to evaluate the role of 5-LOX and leukotrienes. The aim of this study was to investigate the effect of zileuton on prostaglandin (PG) production in vitro and in vivo. EXPERIMENTAL APPROACH Peritoneal macrophages activated with lipopolysaccharide (LPS)/interferon γ (LPS/IFNγ), J774 macrophages and human whole blood stimulated with LPS were used as in vitro models and rat carrageenan-induced pleurisy as an in vivo model. KEY RESULTS Zileuton suppressed PG biosynthesis by interference with arachidonic acid (AA) release in macrophages. We found that zileuton significantly reduced PGE2 and 6-keto prostaglandin F1α (PGF1α) levels in activated mouse peritoneal macrophages and in J774 macrophages. This effect was not related to 5-LOX inhibition, because it was also observed in macrophages from 5-LOX knockout mice. Notably, zileuton inhibited PGE2 production in LPS-stimulated human whole blood and suppressed PGE2 and 6-keto PGF1α pleural levels in rat carrageenan-induced pleurisy. Interestingly, zileuton failed to inhibit the activity of microsomal PGE2 synthase1 and of cyclooxygenase (COX)-2 and did not affect COX-2 expression. However, zileuton significantly decreased AA release in macrophages accompanied by inhibition of phospholipase A2 translocation to cellular membranes. CONCLUSIONS AND IMPLICATION Zileuton inhibited PG production by interfering at the level of AA release. Its mechanism of action, as well as its use as a pharmacological tool, in experimental models of inflammation should be reassessed. PMID:20880396

  1. Significance of CD163-Positive Macrophages in Proliferative Glomerulonephritis.

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    Li, Jun; Liu, Chang-Hua; Xu, Dao-Liang; Gao, Bo

    2015-11-01

    CD163, a marker of M2 macrophages, possesses anti-inflammatory properties. This study aims to investigate the clinicopathological significance of CD163-positive macrophages in proliferative glomerulonephritis. Renal tissue samples from patients with lupus nephritis (LN, n = 22), antineutrophil cytoplasmic autoantibody (ANCA)-associated pauci-immune necrotizing glomerulonephritis (PNGN, n = 10), type 1 membranoproliferative glomerulonephritis (n = 5), minimal change disease (n = 8) and normal control kidneys (n = 3) were included in this study. The expression of CD163, CD68, CD20 and CD3 in renal tissues was detected by immunohistochemistry or immunofluorescence. The level of urinary neutrophil gelatinase-associated lipocalin (NGAL) was determined by enzyme-linked immunosorbent assay. CD163 was mainly expressed in active crescentic glomerulonephritis, proliferative glomerular lesions and areas of tubulointerstitial injury. Patients with LN-IV and PNGN had numerous CD163-positive cells in glomerular and acute tubulointerstitial lesions. CD163-positive cells in glomeruli positively correlated to proteinuria yet negatively correlated to estimated glomerular filtration rate. There was a positive correlation between the number of CD163 cells in acute tubulointerstitial lesions and NGAL levels, whereas a negative correlation between CD163 numbers and estimated glomerular filtration rate. The number of CD163-positive cells in crescentic glomerulonephritis was more than other groups. In LN, the number of CD163 cells in the tubulointerstitial and glomerular lesions had a positive correlation with activity index. Dual staining showed that CD163-positive cells also expressed CD68, although they did not show any staining for CD20 or CD3. CD163-positive macrophages were involved in the pathogenesis of proliferative glomerular lesions, active crescentic glomerulonephritis and acute tubular injury of patients with PNGN and active LN.

  2. Macrophage PPARγ inhibits Gpr132 to mediate the anti-tumor effects of rosiglitazone

    Science.gov (United States)

    Cheng, Wing Yin; Huynh, HoangDinh; Chen, Peiwen; Peña-Llopis, Samuel; Wan, Yihong

    2016-01-01

    Tumor-associated macrophage (TAM) significantly contributes to cancer progression. Human cancer is enhanced by PPARγ loss-of-function mutations, but inhibited by PPARγ agonists such as TZD diabetes drugs including rosiglitazone. However, it remains enigmatic whether and how macrophage contributes to PPARγ tumor-suppressive functions. Here we report that macrophage PPARγ deletion in mice not only exacerbates mammary tumor development but also impairs the anti-tumor effects of rosiglitazone. Mechanistically, we identify Gpr132 as a novel direct PPARγ target in macrophage whose expression is enhanced by PPARγ loss but repressed by PPARγ activation. Functionally, macrophage Gpr132 is pro-inflammatory and pro-tumor. Genetic Gpr132 deletion not only retards inflammation and cancer growth but also abrogates the anti-tumor effects of PPARγ and rosiglitazone. Pharmacological Gpr132 inhibition significantly impedes mammary tumor malignancy. These findings uncover macrophage PPARγ and Gpr132 as critical TAM modulators, new cancer therapeutic targets, and essential mediators of TZD anti-cancer effects. DOI: http://dx.doi.org/10.7554/eLife.18501.001

  3. Siderocalin inhibits the intracellular replication of Mycobacterium tuberculosis in macrophages

    DEFF Research Database (Denmark)

    Johnson, Erin E; Srikanth, Chittur V; Sandgren, Andreas

    2010-01-01

    Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show that sideroc......Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show...... findings are consistent with an important role for siderocalin in protection against M.tb infection and suggest that exogenously administered siderocalin may have therapeutic applications in tuberculosis....

  4. PGC-1β suppresses saturated fatty acid-induced macrophage inflammation by inhibiting TAK1 activation.

    Science.gov (United States)

    Chen, Hongen; Liu, Yan; Li, Di; Song, Jiayi; Xia, Min

    2016-02-01

    Inflammation of infiltrated macrophages in adipose tissue is a key contributor to the initiation of adipose insulin resistance. These macrophages are exposed to high local concentrations of free fatty acids (FFAs) and can be proinflammatory activated by saturated fatty acids (SFAs). However, the regulatory mechanisms on SFA-induced macrophage inflammation are still elusive. Peroxisome proliferator-activated receptor γ coactivator-1β (PGC-1β) is a member of the PGC-1 family of transcriptional coactivators and has been reported to play a key role in SFAs metabolism and in the regulation of inflammatory signaling. However, it remains unclear whether PGC-1β is involved in SFA-induced macrophage inflammation. In this study, we found that PGC-1β expression was significantly decreased in response to palmitic acid (PA) in macrophages in a dose dependent manner. PGC-1β inhibited PA induced TNFα, MCP-1, and IL-1β mRNA and protein expressions. Furthermore, PGC-1β significantly antagonized PA induced macrophage nuclear factor-κB (NF-κB) p65 and JUN N-terminal kinase activation. Mechanistically, we revealed that TGF-β-activated kinase 1 (TAK1) and its adaptor protein TAK1 binding protein 1 (TAB1) played a dominant role in the regulatory effects of PGC-1β. We confirmed that PGC-1β inhibited downstream inflammatory signals via binding with TAB1 and thus preventing TAB1/TAK1 binding and TAK1 activation. Finally, we showed that PGC-1β overexpression in PA treated macrophages improved adipocytes PI3K-Akt insulin signaling in a paracrine fashion. Collectively, our results uncovered a novel mechanism on how macrophage inflammation induced by SFAs was regulated and suggest a potential target in the treatment of obesity induced insulin resistance.

  5. Siderocalin inhibits the intracellular replication of Mycobacterium tuberculosis in macrophages

    DEFF Research Database (Denmark)

    Johnson, Erin E; Srikanth, Chittur V; Sandgren, Andreas;

    2010-01-01

    Siderocalin is a secreted protein that binds to siderophores to prevent bacterial iron acquisition. While it has been shown to inhibit the growth of Mycobacterium tuberculosis (M.tb) in extracellular cultures, its effect on this pathogen within macrophages is not clear. Here, we show...... findings are consistent with an important role for siderocalin in protection against M.tb infection and suggest that exogenously administered siderocalin may have therapeutic applications in tuberculosis....

  6. Interleukin 27 inhibits atherosclerosis via immunoregulation of macrophages in mice.

    Science.gov (United States)

    Hirase, Tetsuaki; Hara, Hiromitsu; Miyazaki, Yoshiyuki; Ide, Noriko; Nishimoto-Hazuku, Ai; Fujimoto, Hirokazu; Saris, Christiaan J M; Yoshida, Hiroki; Node, Koichi

    2013-08-01

    Chronic inflammation in arterial wall that is driven by immune cells and cytokines plays pivotal roles in the development of atherosclerosis. Interleukin 27 (IL-27) is a member of the IL-12 family of cytokines that consists of IL-27p28 and Epstein-Barr virus induced gene 3 (EBI3) and has anti-inflammatory properties that regulate T cell polarization and cytokine production. IL-27-deficient (Ldlr-/-Ebi3-/-) and IL-27 receptor-deficient (Ldlr-/-WSX-1-/-) Ldlr-/- mice were generated and fed with a high-cholesterol diet to induce atherosclerosis. Roles of bone marrow-derived cells in vivo and macrophages in vitro were studied using bone marrow reconstitution by transplantation and cultured peritoneal macrophages, respectively. We demonstrate that mice lacking IL-27 or IL-27 receptor are more susceptible to atherosclerosis compared with wild type due to enhanced accumulation and activation of macrophages in arterial walls. The number of circulating proinflammatory Ly6C(hi) monocytes showed no significant difference between wild-type mice and mice lacking IL-27 or IL-27 receptor. Administration of IL-27 suppressed the development of atherosclerosis in vivo and macrophage activation in vitro that was indicated by increased uptake of modified low-density lipoprotein and augmented production of proinflammatory cytokines. These findings define a novel inhibitory role for IL-27 in atherosclerosis that regulates macrophage activation in mice.

  7. Piperine inhibits ABCA1 degradation and promotes cholesterol efflux from THP-1-derived macrophages

    Science.gov (United States)

    Wang, Limei; Palme, Veronika; Rotter, Susanne; Schilcher, Nicole; Cukaj, Malsor; Wang, Dongdong; Ladurner, Angela; Heiss, Elke H.; Stangl, Herbert; Dirsch, Verena M.; Atanasov, Atanas G.

    2017-01-01

    Scope Increased macrophage cholesterol efflux (ChE) is considered to have anti-atherosclerotic effect counteracting cardiovascular disease. The principle pungent ingredient of the fruits of Piper nigrum, piperine, is identified in this study as a ChE inducer in THP-1-derived macrophages, and mechanisms underlying this effect are explored. Methods and results Without affecting cell viability, piperine concentration-dependently enhances ChE in THP-1-derived macrophages from 25 to 100 μM. The expression level of the key cholesterol transporter protein ATP-binding cassette transporter A1 (ABCA1) is significantly upregulated by piperine, as revealed by western blot analyses. However, two other ChE-mediating transporter proteins, ATP-binding cassette transporter G1 (ABCG1) and scavenger receptor class B member 1 (SR-B1), remain unaffected. Piperine exerts no influence on ABCA1 mRNA levels, but significantly inhibits the degradation of ABCA1, as evident by an increased half-life of the protein in the presence of cycloheximide. Furthermore, it is found that piperine likely interferes with the calpain-mediated ABCA1 degradation pathway and exhibits significant inhibition of calpain activity. Conclusion Our findings suggest that piperine promotes ChE in THP-1-derived macrophages by upregulation of ABCA1, which might be mediated by inhibition of calpain activity. This novel bioactivity makes the dietary constituent piperine a good candidate to be further explored for therapeutic or preventive applications in the context of atherosclerosis. PMID:27862930

  8. Inhibition of M1 macrophage activation in adipose tissue by berberine improves insulin resistance.

    Science.gov (United States)

    Ye, Lifang; Liang, Shu; Guo, Chao; Yu, Xizhong; Zhao, Juan; Zhang, Hao; Shang, Wenbin

    2016-12-01

    Insulin resistance is associated with a chronic inflammation in adipose tissue which is propagated by a phenotypic switch in adipose tissue macrophage (ATM) polarization. This study aimed to investigate whether berberine, the major alkaloid of rhizoma coptidis, can improve insulin resistance through inhibiting ATM activation and inflammatory response in adipose tissue. High-fat-diet induced obese mice were administered oral with berberine (50mg/kg/day) for 14days. ATMs were analysed using FACS and insulin resistance was evaluated. Expressions of pro-inflammatory cytokines and activation of inflammatory pathways were detected. The chemotaxis of macrophages was measured. Glucose consumption and insulin signalling of adipocytes were examined. Berberine significantly decreased F4/80(+)/CD11c(+)/CD206(-) cells in the stromal vascular fraction from adipose tissue and improved glucose tolerance in obsess mice. In addition, berberine reduced the elevated levels of serum TNF-α, IL-6 and MCP-1 and the expressions of TNF-α, IL-6 and MCP-1 and attenuated the phosphorylation of JNK and IKKβ and the expression of NF-κB p65 in the obese adipose tissue, Raw264.7 macrophages and 3T3-L1 adipocytes, respectively. The phosphorylation of IRS-1 (Ser307) was inhibited by berberine in adipose tissue and cultured adipocytes. The phosphorylation of AKT (Ser473) was increased in berberine-treated adipose tissue. Conditioned medium from adipocytes treated with berberine reduced the number of infiltrated macrophages. Berberine partly restored the impaired glucose consumption and the activation of IRS-1 (Ser307) in adipocytes induced by the activation of macrophages. Our findings imply that berberine improves insulin resistance by inhibiting M1 macrophage activation in adipose tissue. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Dehydroepiandrosterone inhibits the spontaneous release of superoxide radical by alveolar macrophages in vitro in asbestosis

    Energy Technology Data Exchange (ETDEWEB)

    Rom, W.N.; Harkin, T. (New York Univ. Medical Center, New York (United States))

    1991-08-01

    Asbestosis is characterized by an alveolar macrophage alveolitis with injury and fibrosis of the lower respiratory tract. Alveolar macrophages recovered by bronchoalveolar lavage spontaneously release exaggerated amounts of oxidants including superoxide anion and hydrogen peroxide that may mediate alveolar epithelial cell injury. Dehydroepiandrosterone (DHEA) is a normally occurring adrenal androgen that inhibits glucose-6-phosphate dehydrogenase, the initial enzyme in the pentose phosphate shunt necessary for NADPH generation and superoxide anion formation. In this regard, the authors hypothesized that DHEA may reduce asbestos-induced oxidant release. DHEA added in vitro to alveolar macrophages lavaged from 11 nonsmoking asbestos workers significantly reduced superoxide anion release. DHEA is an antioxidant and potential anticarcinogenic agent that may have a therapeutic role in reducing the increased oxidant burden in asbestos-induced alveolitis of the lower respiratory tract.

  10. l-Cystathionine Inhibits the Mitochondria-Mediated Macrophage Apoptosis Induced by Oxidized Low Density Lipoprotein

    Science.gov (United States)

    Zhu, Mingzhu; Du, Junbao; Chen, Siyao; Liu, Angie Dong; Holmberg, Lukas; Chen, Yonghong; Zhang, Chunyu; Tang, Chaoshu; Jin, Hongfang

    2014-01-01

    This study was designed to investigate the regulatory role of l-cystathionine in human macrophage apoptosis induced by oxidized low density lipoprotein (ox-LDL) and its possible mechanisms. THP-1 cells were induced with phorbol 12-myristate 13-acetate (PMA) and differentiated into macrophages. Macrophages were incubated with ox-LDL after pretreatment with l-cystathionine. Superoxide anion, apoptosis, mitochondrial membrane potential, and mitochondrial permeability transition pore (MPTP) opening were examined. Caspase-9 activities and expression of cleaved caspase-3 were measured. The results showed that compared with control group, ox-LDL treatment significantly promoted superoxide anion generation, release of cytochrome c (cytc) from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and cell apoptosis, in addition to reduced mitochondrial membrane potential as well as increased MPTP opening. However, 0.3 and 1.0 mmol/L l-cystathionine significantly reduced superoxide anion generation, increased mitochondrial membrane potential, and markedly decreased MPTP opening in ox-LDL + l-cystathionine macrophages. Moreover, compared to ox-LDL treated-cells, release of cytc from mitochondrion into cytoplasm, caspase-9 activities, cleavage of caspase-3, and apoptosis levels in l-cystathionine pretreated cells were profoundly attenuated. Taken together, our results suggested that l-cystathionine could antagonize mitochondria-mediated human macrophage apoptosis induced by ox-LDL via inhibition of cytc release and caspase activation. PMID:25514411

  11. The inhibition of macrophage foam cell formation by tetrahydroxystilbene glucoside is driven by suppressing vimentin cytoskeleton.

    Science.gov (United States)

    Yao, Wenjuan; Huang, Lei; Sun, Qinju; Yang, Lifeng; Tang, Lian; Meng, Guoliang; Xu, Xiaole; Zhang, Wei

    2016-10-01

    Macrophage foam cell formation triggered by oxLDL is an important event that occurs during the development of atherosclerosis. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-d-glucoside (TSG) exhibits significant anti-atherosclerotic activity. Herein we used U937 cells induced by PMA and oxLDL in vitro to investigate the inhibitory effects of TSG on U937 differentiation and macrophage foam cell formation. TSG pretreatment markedly inhibited cell differentiation induced by PMA, macrophage apoptosis and foam cell formation induced by oxLDL. The inhibition of vimentin expression and cleavage was involved in these inhibitory effects of TSG. The suppression of vimentin by siRNA in U937 significantly inhibited cell differentiation, apoptosis and foam cell formation. Using inhibitors for TGFβR1 and PI3K, we found that vimentin production in U937 cells is regulated by TGFβ/Smad signaling, but not by PI3K-Akt-mTOR signaling. Meanwhile, TSG pretreatment inhibited both the expression of TGFβ1 and the phosphorylation of Smad2 and Smad3, and TSG suppressed the nuclear translocation of Smad4 induced by PMA and oxLDL. Furthermore, TSG attenuated the induced caspase-3 activation and adhesion molecules levels by PMA and oxLDL. PMA and oxLDL increased the co-localization of vimentin with ICAM-1, which was attenuated by pretreatment with TSG. These results suggest that TSG inhibits macrophage foam cell formation through suppressing vimentin expression and cleavage, adhesion molecules expression and vimentin-ICAM-1 co-localization. The interruption of TGFβ/Smad pathway and caspase-3 activation is responsible for the downregulation of TSG on vimentin expression and degradation, respectively.

  12. Lipopolysaccharide enhances the inhibition of NF-κB expression in NNK-mediated peritoneal macrophages

    Institute of Scientific and Technical Information of China (English)

    Bin Li; Mei Wu; Xiaoping Liu

    2014-01-01

    The aim of the study was to investigate the efect of lipopolysaccharide (LPS) on the expression of nuclear factor kappa B (NF-κB) in 4-(methylitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-mediated primary mouse peritoneal macrophagesin vitro.Methods: The activity of peritoneal macrophages treated with diferent concentrations of LPS was de-tected by MTT assay in rider to find the optimal concentration. Peritoneal macrophages were also treated with NNK (100-500μM), with or without LPS for 9 h. The expression of NF-κB was demonstrated via immunocytochemistry (ICC) and Western-blot, respectively.Results:The concentration of LPS at 25 μg/mL was found to be the optimal concentration to improve the activity of peritoneal macrophages (P < 0.01). Simultaneously, LPS (25 μg/mL) increased the expression of NF-κB in both the nucleus and cytoplasm and facilitated transfer of NF-κB to the nucleus. NNK treatment significantly inhibited the expression of NF-κB in a concentration-dependent manner, among the LPS-stimulated or unstimulated peritoneal macrophages, espe-cialy when cotreated with LPS (25 μg/mL,P < 0.01 ). Furthermore, NNK treatment (500 μM) with LPS yielded a significant decrease in NF-κB translocation to nucleus and inhibited the expression of NF-κB (P < 0.005).Conclusion: LPS enhances the suppression of NF-κB expression in NNK-mediated mouse peritoneal macrophages, which may provide a theoretical basis for the inhibition of cancer.

  13. Inhibition of P-glycoprotein by HIV protease inhibitors increases intracellular accumulation of berberine in murine and human macrophages.

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    Weibin Zha

    Full Text Available BACKGROUND: HIV protease inhibitor (PI-induced inflammatory response in macrophages is a major risk factor for cardiovascular diseases. We have previously reported that berberine (BBR, a traditional herbal medicine, prevents HIV PI-induced inflammatory response through inhibiting endoplasmic reticulum (ER stress in macrophages. We also found that HIV PIs significantly increased the intracellular concentrations of BBR in macrophages. However, the underlying mechanisms of HIV PI-induced BBR accumulation are unknown. This study examined the role of P-glycoprotein (P-gp in HIV PI-mediated accumulation of BBR in macrophages. METHODOLOGY AND PRINCIPAL FINDINGS: Cultured mouse RAW264.7 macrophages, human THP-1-derived macrophages, Wild type MDCK (MDCK/WT and human P-gp transfected (MDCK/P-gp cells were used in this study. The intracellular concentration of BBR was determined by HPLC. The activity of P-gp was assessed by measuring digoxin and rhodamine 123 (Rh123 efflux. The interaction between P-gp and BBR or HIV PIs was predicated by Glide docking using Schrodinger program. The results indicate that P-gp contributed to the efflux of BBR in macrophages. HIV PIs significantly increased BBR concentrations in macrophages; however, BBR did not alter cellular HIV PI concentrations. Although HIV PIs did not affect P-gp expression, P-gp transport activities were significantly inhibited in HIV PI-treated macrophages. Furthermore, the molecular docking study suggests that both HIV PIs and BBR fit the binding pocket of P-gp, and HIV PIs may compete with BBR to bind P-gp. CONCLUSION AND SIGNIFICANCE: HIV PIs increase the concentration of BBR by modulating the transport activity of P-gp in macrophages. Understanding the cellular mechanisms of potential drug-drug interactions is critical prior to applying successful combinational therapy in the clinic.

  14. Iron oxide nanoparticles inhibit tumour growth by inducing pro-inflammatory macrophage polarization in tumour tissues

    Science.gov (United States)

    Zanganeh, Saeid; Hutter, Gregor; Spitler, Ryan; Lenkov, Olga; Mahmoudi, Morteza; Shaw, Aubie; Pajarinen, Jukka Sakari; Nejadnik, Hossein; Goodman, Stuart; Moseley, Michael; Coussens, Lisa Marie; Daldrup-Link, Heike Elisabeth

    2016-11-01

    Until now, the Food and Drug Administration (FDA)-approved iron supplement ferumoxytol and other iron oxide nanoparticles have been used for treating iron deficiency, as contrast agents for magnetic resonance imaging and as drug carriers. Here, we show an intrinsic therapeutic effect of ferumoxytol on the growth of early mammary cancers, and lung cancer metastases in liver and lungs. In vitro, adenocarcinoma cells co-incubated with ferumoxytol and macrophages showed increased caspase-3 activity. Macrophages exposed to ferumoxytol displayed increased mRNA associated with pro-inflammatory Th1-type responses. In vivo, ferumoxytol significantly inhibited growth of subcutaneous adenocarcinomas in mice. In addition, intravenous ferumoxytol treatment before intravenous tumour cell challenge prevented development of liver metastasis. Fluorescence-activated cell sorting (FACS) and histopathology studies showed that the observed tumour growth inhibition was accompanied by increased presence of pro-inflammatory M1 macrophages in the tumour tissues. Our results suggest that ferumoxytol could be applied 'off label' to protect the liver from metastatic seeds and potentiate macrophage-modulating cancer immunotherapies.

  15. IFN-λ3 inhibits HIV infection of macrophages through the JAK-STAT pathway.

    Directory of Open Access Journals (Sweden)

    Man-Qing Liu

    Full Text Available BACKGROUND: Interferon lambda 3 (IFN-λ3 is a newly identified cytokine with antiviral activity, and its single nucleotide polymorphisms are strongly associated with the treatment effectiveness and development of chronic hepatitis C virus infection. We thus examined the potential of IFN-λ3 to inhibit HIV replication and the possible mechanisms of the anti-HIV action by IFN-λ3 in human macrophages. PRINCIPAL FINDINGS: Under different conditions (before, during, and after HIV infection, IFN-λ3 significantly inhibited viral replication in macrophages, which was associated with the induction of multiple antiviral cellular factors (ISG56, MxA, OAS-1, A3G/F and tetherin and IFN regulatory factors (IRF-1, 3, 5, 7 and 9. This anti-HIV action of IFN-λ3 could be compromised by the JAK-STAT inhibitor. In addition, IFN-λ3 treatment of macrophages induced the expression of toll-like receptor 3 (TLR3 and two key adaptors (MyD88 and TRIF in type I IFN pathway activation. However, HIV infection compromised IFN-λ3-mediated induction of the key elements in JAK-STAT signaling pathway. CONCLUSIONS: These data indicate that IFN-λ3 exerts its anti-HIV function by activating JAK-STAT pathway-mediated innate immunity in macrophages. Future in vivo studies are necessary in order to explore the potential for developing IFN-λ3-based therapy for HIV disease.

  16. Bioactive Extract from Moringa oleifera Inhibits the Pro-inflammatory Mediators in Lipopolysaccharide Stimulated Macrophages

    Science.gov (United States)

    Fard, Masoumeh Tangestani; Arulselvan, Palanisamy; Karthivashan, Govindarajan; Adam, Siti Khadijah; Fakurazi, Sharida

    2015-01-01

    Introduction: Inflammation is a well-known physiological response to protect the body against infection and restore tissue injury. Nevertheless, the chronic inflammation can trigger various inflammatory associated diseases/disorder. Moringa oleifera is a widely grown plant in most tropical countries and it has been recognized traditionally for several medicinal benefits. Objectives: The objective of this study was to investigate the anti-inflammatory properties of M. oleifera extract on lipopolysaccharide (LPS) - stimulated macrophages. Materials and Methods: The anti-inflammatory effect of M. oleifera hydroethanolic bioactive leaves extracts was evaluated by assessing the inhibition of nitric oxide (NO) production during Griess reaction and the expression of pro-inflammatory mediators in macrophages. Results: Interestingly, we found that M. oleifera hydroethanolic bioactive leaves extract significantly inhibited the secretion of NO production and other inflammatory markers such as prostaglandin E2, tumor necrosis factor alpha, interleukin (IL)-6, and IL-1β. Meanwhile, the bioactive extract has induced the production of IL-10 in a dose-dependent manner. In addition, M. oleifera hydroethanolic bioactive leaves extract effectively suppressed the protein expression of inflammatory markers inducible NO synthase, cyclooxygenase-2, and nuclear factor kappa-light-chain-enhancer of activated B-cells p65 in LPS-induced RAW264.7 macrophages in a dose-dependent manner. Conclusion: These findings support the traditional use of M. oleifera plant as an effective treatment for inflammation associated diseases/disorders. SUMMARY Hydroethanolic extracts of Moringa oleifera effectively inhibit the NO production in LPS induced inflammatory model.M. oleifera crude extracts successfully modulate the production of pro-inflammatory mediators in LPS stimulated macrophages.M. oleifera extracts suppressed the expression of inflammatory mediators in LPS stimulated macrophages. PMID:27013794

  17. Bioactive Extract from Moringa oleifera Inhibits the Pro-inflammatory Mediators in Lipopolysaccharide Stimulated Macrophages.

    Science.gov (United States)

    Fard, Masoumeh Tangestani; Arulselvan, Palanisamy; Karthivashan, Govindarajan; Adam, Siti Khadijah; Fakurazi, Sharida

    2015-10-01

    Inflammation is a well-known physiological response to protect the body against infection and restore tissue injury. Nevertheless, the chronic inflammation can trigger various inflammatory associated diseases/disorder. Moringa oleifera is a widely grown plant in most tropical countries and it has been recognized traditionally for several medicinal benefits. The objective of this study was to investigate the anti-inflammatory properties of M. oleifera extract on lipopolysaccharide (LPS) - stimulated macrophages. The anti-inflammatory effect of M. oleifera hydroethanolic bioactive leaves extracts was evaluated by assessing the inhibition of nitric oxide (NO) production during Griess reaction and the expression of pro-inflammatory mediators in macrophages. Interestingly, we found that M. oleifera hydroethanolic bioactive leaves extract significantly inhibited the secretion of NO production and other inflammatory markers such as prostaglandin E2, tumor necrosis factor alpha, interleukin (IL)-6, and IL-1β. Meanwhile, the bioactive extract has induced the production of IL-10 in a dose-dependent manner. In addition, M. oleifera hydroethanolic bioactive leaves extract effectively suppressed the protein expression of inflammatory markers inducible NO synthase, cyclooxygenase-2, and nuclear factor kappa-light-chain-enhancer of activated B-cells p65 in LPS-induced RAW264.7 macrophages in a dose-dependent manner. These findings support the traditional use of M. oleifera plant as an effective treatment for inflammation associated diseases/disorders. Hydroethanolic extracts of Moringa oleifera effectively inhibit the NO production in LPS induced inflammatory model.M. oleifera crude extracts successfully modulate the production of pro-inflammatory mediators in LPS stimulated macrophages.M. oleifera extracts suppressed the expression of inflammatory mediators in LPS stimulated macrophages.

  18. Sulforaphane Inhibits HIV Infection of Macrophages through Nrf2.

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    Andrea Kinga Marias Furuya

    2016-04-01

    Full Text Available Marburg virus, the Kaposi's sarcoma-associated herpesvirus (KSHV and Dengue virus all activate, and benefit from, expression of the transcription regulator nuclear erythroid 2-related factor 2 (Nrf2. The impact of Nrf2 activation on human immunodeficiency virus (HIV infection has not been tested. Sulforaphane (SFN, produced in cruciferous vegetables after mechanical damage, mobilizes Nrf2 to potently reprogram cellular gene expression. Here we show for the first time that SFN blocks HIV infection in primary macrophages but not in primary T cells. Similarly SFN blocks infection in PMA-differentiated promonocytic cell lines, but not in other cell lines tested. siRNA-mediated depletion of Nrf2 boosted HIV infectivity in primary macrophages and reduced the anti-viral effects of SFN treatment. This supports a model in which anti-viral activity is mediated through Nrf2 after it is mobilized by SFN. We further found that, like the type I interferon-induced cellular anti-viral proteins SAMHD1 and MX2, SFN treatment blocks infection after entry, but before formation of 2-LTR circles. Interestingly however, neither SAMHD1 nor MX2 were upregulated. This shows for the first time that Nrf2 action can potently block HIV infection and highlights a novel way to trigger this inhibition.

  19. Curcumin Modulates Macrophage Polarization Through the Inhibition of the Toll-Like Receptor 4 Expression and its Signaling Pathways

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    Yaoyao Zhou

    2015-05-01

    Full Text Available Background: Curcumin, the active ingredient in curcuma rhizomes, has a wide range of therapeutic effects. However, its atheroprotective activity in human acute monocytic leukemia THP-1 cells remains unclear. We investigated the activity and molecular mechanism of action of curcumin in polarized macrophages. Methods: Phorbol myristate acetate (PMA-treated THP-1 cells were differentiated to macrophages, which were further polarized to M1 cells by lipopolysaccharide (LPS; 1 µg/ml and interferon (IFN-γ (20 ng/ml and treated with varying curcumin concentrations. [3H]thymidine (3H-TdR incorporation assays were utilized to measure curcumin-induced growth inhibition. The expression of tumor necrosis factor-a (TNF-a, interleukin (IL-6, and IL-12B (p40 were measured by quantitative real-time polymerase chain reaction (PCR and enzyme-linked immunosorbent assay (ELISA. Macrophage polarization and its mechanism were evaluated by flow cytometry and western blot. Additionally, toll-like receptor 4 (TLR4 small interfering RNA and mitogen-activated protein kinase (MAPK inhibitors were used to further confirm the molecular mechanism of curcumin on macrophage polarization. Results: Curcumin dose-dependently inhibited M1 macrophage polarization and the production of TNF-a, IL-6, and IL-12B (p40. It also decreased TLR4 expression, which regulates M1 macrophage polarization. Furthermore, curcumin significantly inhibited the phosphorylation of ERK, JNK, p38, and nuclear factor (NF-γB. In contrast, SiTLR4 in combination with p-JNK, p-ERK, and p-p38 inhibition reduced the effect of curcumin on polarization. Conclusions: Curcumin can modulate macrophage polarization through TLR4-mediated signaling pathway inhibition, indicating that its effect on macrophage polarization is related to its anti-inflammatory and atheroprotective effects. Our data suggest that curcumin could be used as a therapeutic agent in atherosclerosis.

  20. Allosteric Inhibition of Macrophage Migration Inhibitory Factor Revealed by Ibudilast

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Y.; Crichlow, G; Vermeire, J; Leng, L; Du, X; Hodsdon, M; Bucala, R; Cappello, M; Gross, M; et al.

    2010-01-01

    AV411 (ibudilast; 3-isobutyryl-2-isopropylpyrazolo-[1,5-a]pyridine) is an antiinflammatory drug that was initially developed for the treatment of bronchial asthma but which also has been used for cerebrovascular and ocular indications. It is a nonselective inhibitor of various phosphodiesterases (PDEs) and has varied antiinflammatory activity. More recently, AV411 has been studied as a possible therapeutic for the treatment of neuropathic pain and opioid withdrawal through its actions on glial cells. As described herein, the PDE inhibitor AV411 and its PDE-inhibition-compromised analog AV1013 inhibit the catalytic and chemotactic functions of the proinflammatory protein, macrophage migration inhibitory factor (MIF). Enzymatic analysis indicates that these compounds are noncompetitive inhibitors of the p-hydroxyphenylpyruvate (HPP) tautomerase activity of MIF and an allosteric binding site of AV411 and AV1013 is detected by NMR. The allosteric inhibition mechanism is further elucidated by X-ray crystallography based on the MIF/AV1013 binary and MIF/AV1013/HPP ternary complexes. In addition, our antibody experiments directed against MIF receptors indicate that CXCR2 is the major receptor for MIF-mediated chemotaxis of peripheral blood mononuclear cells.

  1. Leishmania eukaryotic initiation factor (LeIF inhibits parasite growth in murine macrophages.

    Directory of Open Access Journals (Sweden)

    Olga Koutsoni

    Full Text Available The leishmaniases constitute neglected global public health problems that require adequate control measures, prophylactic clinical vaccines and effective and non-toxic drug treatments. In this study, we explored the potential of Leishmania infantum eukaryotic initiation factor (LieIF, an exosomal protein, as a novel anti-infective therapeutic molecule. More specifically, we assessed the efficacy of recombinant LieIF, in combination with recombinant IFN-γ, in eliminating intracellular L. donovani parasites in an in vitro macrophage model. J774A.1 macrophages were initially treated with LieIF/IFN-γ prior to in vitro infection with L. donovani stationary phase promastigotes (pre-infection treatment, and resistance to infection was observed 72 h after infection. J774A.1 macrophages were also treated with LieIF/IFN-γ after L. donovani infection (post-infection treatment, and resistance to infection was also observed at both time points tested (19 h and 72 h after infection. To elucidate the LieIF/IFN-γ-induced mechanism(s that mediate the reduction of intracellular parasite growth, we examined the generation of potent microbicidal molecules, such as nitric oxide (NO and reactive oxygen species (ROS, within infected macrophages. Furthermore, macrophages pre-treated with LieIF/IFN-γ showed a clear up-regulation in macrophage inflammatory protein 1α (MIP-1α as well as tumor necrosis factor alpha (TNF-α expression. However, significant different protein levels were not detected. In addition, macrophages pre-treated with LieIF/IFN-γ combined with anti-TNF-α monoclonal antibody produced significantly lower amounts of ROS. These data suggest that during the pre-treatment state, LieIF induces intramacrophage parasite growth inhibition through the production of TNF-α, which induces microbicidal activity by stimulating NO and ROS production. The mechanisms of NO and ROS production when macrophages are treated with LieIF after infection are probably

  2. Perivascular adipose tissue-derived adiponectin inhibits collar-induced carotid atherosclerosis by promoting macrophage autophagy.

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    Changlong Li

    Full Text Available Adiponectin (APN secreted from perivascular adipose tissue (PVAT is one of the important anti-inflammatory adipokines to inhibit the development of atherosclerosis, but the underlying mechanism has not been clarified. In this study, we aimed to elucidate how APN regulates plaque formation in atherosclerosis.To assess the role of APN secreted by PVAT in atherosclerosis progression, we performed PVAT transplantation experiments on carotid artery atherosclerosis model: ApoE knockout (ApoE-/- mice with a perivascular collar placement around the left carotid artery in combination with a high-fat diet feeding. Our results show that the ApoE-/- mice with PVAT derived from APN knockout (APN-/- mice exhibited accelerated plaque volume formation compared to ApoE-/- mice transplanted with wild-type littermate tissue. Conversely, autophagy in macrophages was significantly attenuated in ApoE-/- mice transplanted with APN-/- mouse-derived PVAT compared to controls. Furthermore, in vitro studies indicate that APN treatment increased autophagy in primary macrophages, as evidenced by increased LC3-I processing and Beclin1 expression, which was accompanied by down-regulation of p62. Moreover, our results demonstrate that APN promotes macrophage autophagy via suppressing the Akt/FOXO3a signaling pathway.Our results indicate that PVAT-secreted APN suppresses plaque formation by inducing macrophage autophagy.

  3. Brucella infection inhibits macrophages apoptosis via Nedd4-dependent degradation of calpain2.

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    Cui, Guimei; Wei, Pan; Zhao, Yuxi; Guan, Zhenhong; Yang, Li; Sun, Wanchun; Wang, Shuangxi; Peng, Qisheng

    2014-11-07

    The calcium-dependent protease calpain2 is involved in macrophages apoptosis. Brucella infection-induced up-regulation of intracellular calcium level is an essential factor for the intracellular survival of Brucella within macrophages. Here, we hypothesize that calcium-dependent E3 ubiquitin ligase Nedd4 ubiquitinates calpain2 and inhibits Brucella infection-induced macrophage apoptosis via degradation of calpain2.Our results reveal that Brucella infection induces increases in Nedd4 activity in an intracellular calcium dependent manner. Furthermore, Brucella infection-induced degradation of calpain2 is mediated by Nedd4 ubiquitination of calpain2. Brucella infection-induced calpain2 degradation inhibited macrophages apoptosis. Treatment of Brucella infected macrophages with calcium chelator BAPTA or Nedd4 knock-down decreased Nedd4 activity, prevented calpain2 degradation, and resulted in macrophages apoptosis.

  4. Bioactive extract from moringa oleifera inhibits the pro-inflammatory mediators in lipopolysaccharide stimulated macrophages

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    Masoumeh Tangestani Fard

    2015-01-01

    Full Text Available Introduction: Inflammation is a well-known physiological response to protect the body against infection and restore tissue injury. Nevertheless, the chronic inflammation can trigger various inflammatory associated diseases/disorder. Moringa oleifera is a widely grown plant in most tropical countries and it has been recognized traditionally for several medicinal benefits. Objectives: The objective of this study was to investigate the anti-inflammatory properties of M. oleifera extract on lipopolysaccharide (LPS - stimulated macrophages. Materials and Methods: The anti-inflammatory effect of M. oleifera hydroethanolic bioactive leaves extracts was evaluated by assessing the inhibition of nitric oxide (NO production during Griess reaction and the expression of pro-inflammatory mediators in macrophages. Results: Interestingly, we found that M. oleifera hydroethanolic bioactive leaves extract significantly inhibited the secretion of NO production and other inflammatory markers such as prostaglandin E 2 , tumor necrosis factor alpha, interleukin (IL-6, and IL-1b. Meanwhile, the bioactive extract has induced the production of IL-10 in a dose-dependent manner. In addition, M. oleifera hydroethanolic bioactive leaves extract effectively suppressed the protein expression of inflammatory markers inducible NO synthase, cyclooxygenase-2, and nuclear factor kappa-light-chain-enhancer of activated B-cells p65 in LPS-induced RAW264.7 macrophages in a dose-dependent manner. Conclusion: These findings support the traditional use of M. oleifera plant as an effective treatment for inflammation associated diseases/disorders.

  5. Inhibition of HIV-1 replication in human monocyte-derived macrophages by parasite Trypanosoma cruzi.

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    Guadalupe Andreani

    Full Text Available BACKGROUND: Cells of monocyte/macrophage lineage are one of the major targets of HIV-1 infection and serve as reservoirs for viral persistence in vivo. These cells are also the target of the protozoa Trypanosoma cruzi, the causative agent of Chagas disease, being one of the most important endemic protozoonoses in Latin America. It has been demonstrated in vitro that co-infection with other pathogens can modulate HIV replication. However, no studies at cellular level have suggested an interaction between T. cruzi and HIV-1 to date. METHODOLOGY/PRINCIPAL FINDINGS: By using a fully replicative wild-type virus, our study showed that T. cruzi inhibits HIV-1 antigen production by nearly 100% (p99% being stronger than HIV-T. cruzi (approximately 90% for BaL and approximately 85% for VSV-G infection. In MDM with established HIV-1 infection, T. cruzi significantly inhibited luciferate activity (p<0.01. By quantifying R-U5 and U5-gag transcripts by real time PCR, our study showed the expression of both transcripts significantly diminished in the presence of trypomastigotes (p<0.05. Thus, T. cruzi inhibits viral post-integration steps, early post-entry steps and entry into MDM. Trypomastigotes also caused a approximately 60-70% decrease of surface CCR5 expression on MDM. Multiplication of T. cruzi inside the MDM does not seem to be required for inhibiting HIV-1 replication since soluble factors secreted by trypomastigotes have shown similar effects. Moreover, the major parasite antigen cruzipain, which is secreted by the trypomastigote form, was able to inhibit viral production in MDM over 90% (p<0.01. CONCLUSIONS/SIGNIFICANCE: Our study showed that T. cruzi inhibits HIV-1 replication at several replication stages in macrophages, a major cell target for both pathogens.

  6. Tumor-Associated Macrophages Provide Significant Prognostic Information in Urothelial Bladder Cancer.

    Directory of Open Access Journals (Sweden)

    Minna M Boström

    Full Text Available Inflammation is an important feature of carcinogenesis. Tumor-associated macrophages (TAMs can be associated with either poor or improved prognosis, depending on their properties and polarization. Current knowledge of the prognostic significance of TAMs in bladder cancer is limited and was investigated in this study. We analyzed 184 urothelial bladder cancer patients undergoing transurethral resection of a bladder tumor or radical cystectomy. CD68 (pan-macrophage marker, MAC387 (polarized towards type 1 macrophages, and CLEVER-1/Stabilin-1 (type 2 macrophages and lymphatic/blood vessels were detected immunohistochemically. The median follow-up time was 6.0 years. High macrophage counts associated with a higher pT category and grade. Among patients undergoing transurethral resection, all studied markers apart from CLEVER-1/Stabilin-1 were associated with increased risk of progression and poorer disease-specific and overall survival in univariate analyses. High levels of two macrophage markers (CD68/MAC387+/+ or CD68/CLEVER-1+/+ groups had an independent prognostic role after transurethral resection in multivariate analyses. In the cystectomy cohort, MAC387, alone and in combination with CD68, was associated with poorer survival in univariate analyses, but none of the markers were independent predictors of outcome in multivariate analyses. In conclusion, this study demonstrates that macrophage phenotypes provide significant independent prognostic information, particularly in bladder cancers undergoing transurethral resection.

  7. Systemic and Cardiac Depletion of M2 Macrophage through CSF-1R Signaling Inhibition Alters Cardiac Function Post Myocardial Infarction.

    Science.gov (United States)

    Leblond, Anne-Laure; Klinkert, Kerstin; Martin, Kenneth; Turner, Elizebeth C; Kumar, Arun H; Browne, Tara; Caplice, Noel M

    2015-01-01

    The heart hosts tissue resident macrophages which are capable of modulating cardiac inflammation and function by multiple mechanisms. At present, the consequences of phenotypic diversity in macrophages in the heart are incompletely understood. The contribution of cardiac M2-polarized macrophages to the resolution of inflammation and repair response following myocardial infarction remains to be fully defined. In this study, the role of M2 macrophages was investigated utilising a specific CSF-1 receptor signalling inhibition strategy to achieve their depletion. In mice, oral administration of GW2580, a CSF-1R kinase inhibitor, induced significant decreases in Gr1lo and F4/80hi monocyte populations in the circulation and the spleen. GW2580 administration also induced a significant depletion of M2 macrophages in the heart after 1 week treatment as well as a reduction of cardiac arginase1 and CD206 gene expression indicative of M2 macrophage activity. In a murine myocardial infarction model, reduced M2 macrophage content was associated with increased M1-related gene expression (IL-6 and IL-1β), and decreased M2-related gene expression (Arginase1 and CD206) in the heart of GW2580-treated animals versus vehicle-treated controls. M2 depletion was also associated with a loss in left ventricular contractile function, infarct enlargement, decreased collagen staining and increased inflammatory cell infiltration into the infarct zone, specifically neutrophils and M1 macrophages. Taken together, these data indicate that CSF-1R signalling is critical for maintaining cardiac tissue resident M2-polarized macrophage population, which is required for the resolution of inflammation post myocardial infarction and, in turn, for preservation of ventricular function.

  8. BZ-26, a novel GW9662 derivate, attenuated inflammation by inhibiting the differentiation and activation of inflammatory macrophages.

    Science.gov (United States)

    Bei, Yuncheng; Chen, Jiajia; Zhou, Feifei; Huang, Yahong; Jiang, Nan; Tan, Renxiang; Shen, Pingping

    2016-12-01

    Peroxisome proliferator-activated receptor-gamma (PPARγ) is considered to be an important transcriptional factor in regulation of macrophages differentiation and activation. We have synthesized a series of novel structural molecules based on GW9662's structure (named BZ-24, BZ-25 and BZ-26), and interaction activity was calculated by computational docking. BZ-26 had shown stronger interaction with PPARγ and had higher transcriptional inhibitory activity of PPARγ with lower dosage compared with GW9662. BZ-26 was proved to inhibit inflammatory macrophage differentiation. LPS-induced acute inflammation mouse model was applied to demonstrate its anti-inflammatory activity. And the results showed that BZ-26 administration attenuated plasma tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) secretion, which are vital cytokines in acute inflammation. The anti-inflammatory activity was examined in THP-1 cell line, and TNF-α, IL-6 and MCP-1, were significantly inhibited. The results of Western blot and luciferase reporter assay indicated that BZ-26 not only inhibited NF-κB transcriptional activity, but also abolished LPS-induce nuclear translocation of P65. We also test BZ-26 action in tumor-bearing chronic inflammation mouse model, and BZ-26 was able to alter macrophages phenotype, resulting in antitumor effect. All our data revealed that BZ-26 modulated LPS-induced acute inflammation via inhibiting inflammatory macrophages differentiation and activation, potentially via inhibition of NF-κB signal pathway.

  9. Short Communication: HIV Controller T Cells Effectively Inhibit Viral Replication in Alveolar Macrophages.

    Science.gov (United States)

    Walker-Sperling, Victoria E; Merlo, Christian A; Buckheit, Robert W; Lambert, Allison; Tarwater, Patrick; Kirk, Greg D; Drummond, M Bradley; Blankson, Joel N

    Macrophages are targets of HIV-1 infection, and control of viral replication within these cells may be an important component of a T-cell-based vaccine. Although several studies have analyzed the ability of CD8(+) T cells to inhibit viral replication in monocyte-derived macrophages, the effect of T cells on HIV-1-infected tissue macrophages is less clear. We demonstrate here that both CD4(+) and CD8(+) T-cell effectors from HIV controllers are capable of suppressing viral replication in bronchoalveolar lavage-derived alveolar macrophages. These findings have implications for HIV-1 vaccine and eradication strategies.

  10. Inhibition of transglutaminase 2 reduces efferocytosis in human macrophages: Role of CD14 and SR-AI receptors.

    Science.gov (United States)

    Eligini, S; Fiorelli, S; Tremoli, E; Colli, S

    2016-10-01

    Transglutaminase 2 (TGM2), a member of the transglutaminase family of enzymes, is a multifunctional protein involved in numerous events spanning from cell differentiation, to signal transduction, apoptosis, and wound healing. It is expressed in a variety of cells, macrophages included. Macrophage TGM2 promotes the clearance of apoptotic cells (efferocytosis) and emerging evidence suggests that defective efferocytosis contributes to the consequences of inflammation-associated diseases, including atherosclerotic lesion progression and its sequelae. Of interest, active TGM2 identified in human atherosclerotic lesions plays critical roles in plaque stability through effects on matrix cross-linking and TGFβ activity. This study explores the mechanisms by which TGM2 controls efferocytosis in human macrophages. Herein we show that TGM2 increases progressively during monocyte differentiation towards macrophages and controls their efferocytic potential as well as morphology and viability. Two experimental approaches that took advantage of the inhibition of TGM2 activity and protein silencing give proof that TGM2 reduction significantly impairs macrophage efferocytosis. Among the mechanisms involved we highlighted a role of the receptors CD14 and SR-AI whose levels were markedly reduced by TGM2 inhibition. Conversely, CD36 receptor and αvβ3 integrin levels were not influenced. Of note, lipid accumulation and IL-10 secretion were reduced in macrophages displaying defective efferocytosis. Overall, our data define a crucial role of TGM2 activity during macrophage differentiation via mechanisms involving CD14 and SR-AI receptors and show that TGM2 inhibition triggers a pro-inflammatory phenotype. Copyright © 2016 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

  11. Tim-3 inhibits macrophage control of Listeria monocytogenes by inhibiting Nrf2

    Science.gov (United States)

    Wang, Zhiding; Sun, Dejun; Chen, Guojiang; Li, Ge; Dou, Shuaijie; Wang, Renxi; Xiao, He; Hou, Chunmei; Li, Yan; Feng, Jiannan; Shen, Beifen; Han, Gencheng

    2017-01-01

    T cell immunoglobulin mucin-3 (Tim-3) is an immune checkpoint inhibitor and its dysregulation has been related to T cell tolerance and many immune disorders, such as tumors and infection tolerance. However, the physiopathology roles of Tim-3 in innate immunity remain elusive. Here, we demonstrate that Tim-3 inhibits macrophage phagocytosis of L. monocytogenes by inhibiting the nuclear erythroid 2-related factor 2 (Nrf2) signaling pathway and increases bacterial burden. Tim-3 signaling promotes Nrf2 degradation by increasing its ubiquitination and, as a result, decreasing its nuclear translocation. CD36 and heme oxygenase-1 (HO-1), two downstream molecules in the Tim-3-Nrf2 signaling axis, are involved in the Tim-3- mediated immune evasion of L. monocytogenes both in vitro and in vivo. We here identified new mechanisms by which Tim-3 induces infection tolerance. By modulating the Tim-3 pathway, we demonstrate the feasibility of manipulating macrophage function as a potent tool for treating infectious diseases, such as Listeria infection. PMID:28205579

  12. Leishmania-mediated inhibition of iron export promotes parasite replication in macrophages.

    Directory of Open Access Journals (Sweden)

    Rym Ben-Othman

    2014-01-01

    Full Text Available Leishmania parasites infect macrophages, cells that play an important role in organismal iron homeostasis. By expressing ferroportin, a membrane protein specialized in iron export, macrophages release iron stored intracellularly into the circulation. Iron is essential for the intracellular replication of Leishmania, but how the parasites compete with the iron export function of their host cell is unknown. Here, we show that infection with Leishmania amazonensis inhibits ferroportin expression in macrophages. In a TLR4-dependent manner, infected macrophages upregulated transcription of hepcidin, a peptide hormone that triggers ferroportin degradation. Parasite replication was inhibited in hepcidin-deficient macrophages and in wild type macrophages overexpressing mutant ferroportin that is resistant to hepcidin-induced degradation. Conversely, intracellular growth was enhanced by exogenously added hepcidin, or by expression of dominant-negative ferroportin. Importantly, dominant-negative ferroportin and macrophages from flatiron mice, a mouse model for human type IV hereditary hemochromatosis, restored the infectivity of mutant parasite strains defective in iron acquisition. Thus, inhibition of ferroportin expression is a specific strategy used by L. amazonensis to inhibit iron export and promote their own intracellular growth.

  13. Nimbolide Inhibits Nuclear Factor-КB Pathway in Intestinal Epithelial Cells and Macrophages and Alleviates Experimental Colitis in Mice.

    Science.gov (United States)

    Seo, Ji Yeon; Lee, Changhyun; Hwang, Sung Wook; Chun, Jaeyoung; Im, Jong Pil; Kim, Joo Sung

    2016-10-01

    Nimbolide is a limonoid extracted from neem tree (Azadirachta indica) that has antiinflammatory properties. The effect of nimbolide on the nuclear factor-kappa B (NF-κB) pathway in intestinal epithelial cells (IECs), macrophages and in murine colitis models was investigated. The IEC COLO 205, the murine macrophage cell line RAW 264.7, and peritoneal macrophages from interleukin-10-deficient (IL-10(-/-) ) mice were preconditioned with nimbolide and then stimulated with tumor necrosis factor-α (TNF-α) or lipopolysaccharide. Dextran sulfate sodium-induced acute colitis model and chronic colitis model in IL-10(-/-) mice were used for in vivo experiments. Nimbolide significantly suppressed the expression of inflammatory cytokines (IL-6, IL-8, IL-12, and TNF-α) and inhibited the phosphorylation of IκBα and the DNA-binding affinity of NF-κB in IECs and macrophages. Nimbolide ameliorated weight loss, colon shortening, disease activity index score, and histologic scores in dextran sulfate sodium colitis. It also improved histopathologic scores in the chronic colitis of IL-10(-/-) mice. Staining for phosphorylated IκBα was significantly decreased in the colon tissue after treatment with nimbolide in both models. Nimbolide inhibits NF-κB signaling in IECs and macrophages and ameliorates experimental colitis in mice. These results suggest nimbolide could be a potentially new treatment for inflammatory bowel disease. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  14. Chloroquine inhibits Rhodococcus equi replication in murine and foal alveolar macrophages by iron-starvation.

    Science.gov (United States)

    Gressler, Leticia T; Bordin, Angela I; McQueen, Cole M; Cohen, Noah D; de Vargas, Agueda Castagna

    2016-05-30

    Rhodococcus equi preferentially infects macrophages causing pyogranulomatous pneumonia in young foals. Both the vapA and rhbC genes are up-regulated in an iron (Fe)-deprived environment, such as that found within macrophages. Chloroquine (CQ) is a drug widely used against malaria that suppresses the intracellular availability of Fe in eukaryotic cells. The main objective of this study was to evaluate the ability of CQ to inhibit replication of virulent R. equi within murine (J774A.1) and foal alveolar macrophages (AMs) and to verify whether the mechanism of inhibition could be Fe-deprivation-dependent. CQ effect on R. equi extracellular survival and toxicity to J774A.1 were evaluated. R. equi survival within J774A.1 and foal AMs was evaluated under CQ (10 and 20μM), bovine saturated transferrin (bHTF), and bovine unsaturated transferrin (bATF) exposure. To explore the action mechanism of CQ, the superoxide anion production, the lysozyme activity, as well as the relative mRNA expression of vapA and rhbC were examined. CQ at≤20μM had no effect on R. equi extracellular multiplication and J774A.1 viability. Exposure to CQ significantly and markedly reduced survival of R. equi within J774A.1 and foal AMs. Treatment with bHTF did not reverse CQ effect on R. equi. Exposure to CQ did not affected superoxide anion production or lysozyme activity, however vapA and rhbC expression was significantly increased. Our results reinforce the hypothesis that intracellular availability of Fe is required for R. equi survival, and our initial hypothesis that CQ can limit replication of R. equi in J774A.1 and foal AMs, most likely by Fe starvation. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Inhibition of CDKS by roscovitine suppressed LPS-induced *NO production through inhibiting NFkappaB activation and BH4 biosynthesis in macrophages.

    Science.gov (United States)

    Du, Jianhai; Wei, Na; Guan, Tongju; Xu, Hao; An, Jianzhong; Pritchard, Kirkwood A; Shi, Yang

    2009-09-01

    In inflammatory diseases, tissue damage is critically associated with nitric oxide ((*)NO) and cytokines, which are overproduced in response to cellular release of endotoxins. Here we investigated the inhibitory effect of roscovitine, a selective inhibitor of cyclin-dependent kinases (CDKs) on (*)NO production in mouse macrophages. In RAW264.7 cells, we found that roscovitine abolished the production of (*)NO induced by lipopolysaccharide (LPS). Moreover, roscovitine significantly inhibited LPS-induced inducible nitric oxide synthase (iNOS) mRNA and protein expression. Our data also showed that roscovitine attenuated LPS-induced phosphorylation of IkappaB kinase beta (IKKbeta), IkappaB, and p65 but enhanced the phosphorylation of ERK, p38, and c-Jun NH(2)-terminal kinase (JNK). In addition, roscovitine dose dependently inhibited LPS-induced expression of cyclooxygenase-2 (COX)-2, IL-1beta, and IL-6 but not tumor necrosis factor (TNF)-alpha. Tetrahydrobiopterin (BH(4)), an essential cofactor for iNOS, is easily oxidized to 7,8-dihydrobiopterin (BH(2)). Roscovitine significantly inhibited LPS-induced BH(4) biosynthesis and decreased BH(4)-to-BH(2) ratio. Furthermore, roscovitine greatly reduced the upregulation of GTP cyclohydrolase-1 (GCH-1), the rate-limiting enzyme for BH(4) biosynthesis. Using other CDK inhibitors, we found that CDK1, CDK5, and CDK7, but not CDK2, significantly inhibited LPS-induced (*)NO production in macrophages. Similarly, in isolated peritoneal macrophages, roscovitine strongly inhibited (*)NO production, iNOS, and COX-2 upregulation, activation of NFkappaB, and induction of GCH-1 by LPS. Together, our data indicate that roscovitine abolishes LPS-induced (*)NO production in macrophages by suppressing nuclear factor-kappaB activation and BH(4) biosynthesis, which might be mediated by CDK1, CDK5, and CDK7. Our results also suggest that roscovitine may inhibit inflammation and that CDKs may play important roles in the mechanisms by which

  16. Metformin reduces lipid accumulation in macrophages by inhibiting FOXO1-mediated transcription of fatty acid-binding protein 4

    Energy Technology Data Exchange (ETDEWEB)

    Song, Jun [Qilu Hospital, Shandong University, Jinan, Shandong (China); Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Ren, Pingping; Zhang, Lin [Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Wang, Xing Li [Qilu Hospital, Shandong University, Jinan, Shandong (China); Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States); Chen, Li [Qilu Hospital, Shandong University, Jinan, Shandong (China); Shen, Ying H., E-mail: hyshen@bcm.edu [Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, TX (United States); Texas Heart Institute at St. Luke' s Episcopal Hospital, Houston, TX (United States)

    2010-02-26

    Objective: The accumulation of lipids in macrophages contributes to the development of atherosclerosis. Strategies to reduce lipid accumulation in macrophages may have therapeutic potential for preventing and treating atherosclerosis and cardiovascular complications. The antidiabetic drug metformin has been reported to reduce lipid accumulation in adipocytes. In this study, we examined the effects of metformin on lipid accumulation in macrophages and investigated the mechanisms involved. Methods and results: We observed that metformin significantly reduced palmitic acid (PA)-induced intracellular lipid accumulation in macrophages. Metformin promoted the expression of carnitine palmitoyltransferase I (CPT-1), while reduced the expression of fatty acid-binding protein 4 (FABP4) which was involved in PA-induced lipid accumulation. Quantitative real-time PCR showed that metformin regulates FABP4 expression at the transcriptional level. We identified forkhead transcription factor FOXO1 as a positive regulator of FABP4 expression. Inhibiting FOXO1 expression with FOXO1 siRNA significantly reduced basal and PA-induced FABP4 expression. Overexpression of wild-type FOXO1 and constitutively active FOXO1 significantly increased FABP4 expression, whereas dominant negative FOXO1 dramatically decreased FABP4 expression. Metformin reduced FABP4 expression by promoting FOXO1 nuclear exclusion and subsequently inhibiting its activity. Conclusions: Taken together, these results suggest that metformin reduces lipid accumulation in macrophages by repressing FOXO1-mediated FABP4 transcription. Thus, metformin may have a protective effect against lipid accumulation in macrophages and may serve as a therapeutic agent for preventing and treating atherosclerosis in metabolic syndrome.

  17. Compound C inhibits macrophage chemotaxis through an AMPK-independent mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngyi [College of Pharmacy, Woosuk University, Wanju, Jeonbuk 55338 (Korea, Republic of); Department of Biochemistry, Chonbuk National University Medical School, Jeonju, Jeonbuk 54896 (Korea, Republic of); Park, Byung-Hyun, E-mail: bhpark@jbnu.ac.kr [Department of Biochemistry, Chonbuk National University Medical School, Jeonju, Jeonbuk 54896 (Korea, Republic of); Bae, Eun Ju, E-mail: ejbae@woosuk.ac.kr [College of Pharmacy, Woosuk University, Wanju, Jeonbuk 55338 (Korea, Republic of)

    2016-01-15

    Macrophage infiltration in adipose tissue is a well-established cause of obesity-linked insulin resistance. AMP-activated protein kinase (AMPK) activation in peripheral tissues such as adipose tissue has beneficial effects on the protection against obesity-induced insulin resistance, which is mainly mediated by prevention of adipose tissue macrophage infiltration and inflammation. In examining the role of AMPK on adipose tissue inflammation, we unexpectedly found that compound C (CC), despite its inhibition of AMPK, robustly inhibited macrophage chemotaxis in RAW 264.7 cells when adipocyte conditioned medium (CM) was used as a chemoattractant. Here, we report that CC inhibition of macrophage migration occurred independently of AMPK. Mechanistically, this inhibitory effect of cell migration by CC was mediated by inhibition of the focal adhesion kinase, AKT, nuclear factor κB pathways. Moreover, the expression of chemokine monocyte chemoattractant protein-1 and pro-inflammatory genes such as tumor necrosis factor α and inducible nitric oxide synthase were prevented by CC treatment in RAW 264.7 cells stimulated with either adipocyte CM or lipopolysaccharide. Lastly, in accord with the findings of the anti-inflammatory effect of CC, we demonstrated that CC functioned as a repressor of macrophage CM-mediated insulin resistance in adipocytes. Taken together, our results suggest that CC serves as a useful inhibitory molecule against macrophage chemotaxis into adipose tissue and thus might have therapeutic potential for the treatment of obesity-linked adipose inflammation. - Highlights: • Compound C (CC) inhibits macrophage chemotaxis regardless of AMPK suppression. • CC enhances insulin sensitivity in adipocytes. • CC inhibits focal adhesion kinase, AKT, and NF-κB signaling in RAW 264.7 cells.

  18. Fibronectin inhibits cytokine production induced by CpG DNA in macrophages without direct binding to DNA.

    Science.gov (United States)

    Yoshida, Hiroyuki; Nishikawa, Makiya; Yasuda, Sachiyo; Toyota, Hiroyasu; Kiyota, Tsuyoshi; Takahashi, Yuki; Takakura, Yoshinobu

    2012-10-01

    Fibronectin (FN) is known to have four DNA-binding domains although their physiological significance is unknown. Primary murine peritoneal macrophages have been shown to exhibit markedly lower responsiveness to CpG motif-replete plasmid DNA (pDNA), Toll-like receptor-9 (TLR9) ligand, compared with murine macrophage-like cell lines. The present study was conducted to examine whether FN having DNA-binding domains is involved in this phenomenon. The expression of FN was significantly higher in primary macrophages than in a macrophage-like cell line, RAW264.7, suggesting that abundant FN might suppress the responsiveness in the primary macrophages. However, electrophoretic analysis revealed that FN did not bind to pDNA in the presence of a physiological concentration of divalent cations. Surprisingly, marked tumor necrosis factor - (TNF-)α production from murine macrophages upon CpG DNA stimulation was significantly reduced by exogenously added FN in a concentration-dependent manner but not by BSA, laminin or collagen. FN did not affect apparent pDNA uptake by the cells. Moreover, FN reduced TNF-α production induced by polyI:C (TLR3 ligand), and imiquimod (TLR7 ligand), but not by LPS (TLR4 ligand), or a non-CpG pDNA/cationic liposome complex. The confocal microscopic study showed that pDNA was co-localized with FN in the same intracellular compartment in RAW264.7, suggesting that FN inhibits cytokine signal transduction in the endosomal/lysosomal compartment. Taken together, the results of the present study has revealed, for the first time, a novel effect of FN whereby the glycoprotein modulates cytokine signal transduction via CpG-DNA/TLR9 interaction in macrophages without direct binding to DNA through its putative DNA-binding domains.

  19. Human lung-resident macrophages express CB1 and CB2 receptors whose activation inhibits the release of angiogenic and lymphangiogenic factors.

    Science.gov (United States)

    Staiano, Rosaria I; Loffredo, Stefania; Borriello, Francesco; Iannotti, Fabio Arturo; Piscitelli, Fabiana; Orlando, Pierangelo; Secondo, Agnese; Granata, Francescopaolo; Lepore, Maria Teresa; Fiorelli, Alfonso; Varricchi, Gilda; Santini, Mario; Triggiani, Massimo; Di Marzo, Vincenzo; Marone, Gianni

    2016-04-01

    Macrophages are pivotal effector cells in immune responses and tissue remodeling by producing a wide spectrum of mediators, including angiogenic and lymphangiogenic factors. Activation of cannabinoid receptor types 1 and 2 has been suggested as a new strategy to modulate angiogenesis in vitro and in vivo. We investigated whether human lung-resident macrophages express a complete endocannabinoid system by assessing their production of endocannabinoids and expression of cannabinoid receptors. Unstimulated human lung macrophage produce 2-arachidonoylglycerol,N-arachidonoyl-ethanolamine,N-palmitoyl-ethanolamine, and N-oleoyl-ethanolamine. On LPS stimulation, human lung macrophages selectively synthesize 2-arachidonoylglycerol in a calcium-dependent manner. Human lung macrophages express cannabinoid receptor types 1 and 2, and their activation induces ERK1/2 phosphorylation and reactive oxygen species generation. Cannabinoid receptor activation by the specific synthetic agonists ACEA and JWH-133 (but not the endogenous agonist 2-arachidonoylglycerol) markedly inhibits LPS-induced production of vascular endothelial growth factor-A, vascular endothelial growth factor-C, and angiopoietins and modestly affects IL-6 secretion. No significant modulation of TNF-α or IL-8/CXCL8 release was observed. The production of vascular endothelial growth factor-A by human monocyte-derived macrophages is not modulated by activation of cannabinoid receptor types 1 and 2. Given the prominent role of macrophage-assisted vascular remodeling in many tumors, we identified the expression of cannabinoid receptors in lung cancer-associated macrophages. Our results demonstrate that cannabinoid receptor activation selectively inhibits the release of angiogenic and lymphangiogenic factors from human lung macrophage but not from monocyte-derived macrophages. Activation of cannabinoid receptors on tissue-resident macrophages might be a novel strategy to modulate macrophage-assisted vascular remodeling

  20. Inhibition of IRF8 Negatively Regulates Macrophage Function and Impairs Cutaneous Wound Healing.

    Science.gov (United States)

    Guo, Yuanyuan; Yang, Zhiyin; Wu, Shan; Xu, Peng; Peng, Yinbo; Yao, Min

    2017-02-01

    The inflammatory response is essential for normal cutaneous wound healing. Macrophages, as critical inflammatory cells, coordinate inflammation and angiogenesis phases during wound healing. It has been reported that the transcription factor interferon regulatory factor 8 (IRF8), a member of the IRF family, plays a critical role in the development and function of macrophages and is associated with inflammation. However, the role of IRF8 in cutaneous wound healing and its underlying mechanism remain elusive. Through immunohistochemical (IHC) staining, we showed that IRF8 is involved in the wound repair process in mice and patients. Furthermore, we ascertain that the repression of IRF8 by small interfering RNA (siRNA) leads to delayed wound healing. To explore the mechanism by which IRF8 impacts wound healing, we observed its effect on macrophage-related mediators by IHC or real-time PCR. The results demonstrated that the inhibition of IRF8 decreases the mRNA expression of inflammatory mediators associated with M1 macrophage (il-1b, il-6, inos, and tnf-a) but no impact on M2 macrophage-related mediators (arg-1, mrc-1, and il-10) and the number of macrophages in the wounds. Furthermore, the inhibition of IRF8 induced apoptosis in the wounds. In summary, this study demonstrates that the down-regulation of IRF8 in the wound leads to impaired wound healing possibly through the regulation of macrophage function and apoptosis in skin wound.

  1. Tim-3 promotes intestinal homeostasis in DSS colitis by inhibiting M1 polarization of macrophages.

    Science.gov (United States)

    Jiang, Xingwei; Yu, Jiahui; Shi, Qingzhu; Xiao, Yan; Wang, Wei; Chen, Guojiang; Zhao, Zhi; Wang, Renxi; Xiao, He; Hou, Chunmei; Feng, Jiannan; Ma, Yuanfang; Shen, Beifen; Wang, Lili; Li, Yan; Han, Gencheng

    2015-10-01

    Tim-3 is involved in the physiopathology of inflammatory bowel disease (IBD), but the underlying mechanism is unknown. Here, we demonstrated that, in mouse with DSS colitis, Tim-3 inhibited the polarization of pathogenic pro-inflammatory M1 macrophages, while Tim-3 downregulation or blockade resulted in an increased M1 response. Adoptive transfer of Tim-3-silenced macrophages worsened DSS colitis and enhanced inflammation, while Tim-3 overexpression attenuated DSS colitis by decreasing the M1 macrophage response. Co-culture of Tim-3-overexpressing macrophages with intestinal lymphocytes decreased the pro-inflammatory response. Tim-3 shaped intestinal macrophage polarization may be TLR-4 dependent since Tim-3 blockade failed to exacerbate colitis or increase M1 macrophage response in the TLR-4 KO model. Finally, Tim-3 signaling inhibited phosphorylation of IRF3, a TLR-4 downstream transcriptional factor regulating macrophage polarization. A better understanding of this pathway may shed new light on colitis pathogenesis and result in a new therapeutic strategy.

  2. β-elemene inhibits tumor-promoting effect of M2 macrophages in lung cancer.

    Science.gov (United States)

    Yu, Xiaomu; Xu, Maoyi; Li, Na; Li, Zongjuan; Li, Hongye; Shao, Shujuan; Zou, Kun; Zou, Lijuan

    2017-08-19

    Macrophages in tumor are mostly M2-polarized and have been reported to promote tumorigenesis, which are also defined as tumor-associated macrophages (TAMs). β-elemene has therapeutic effects against several cancers, however, it remains unknown whether β-elemene could inhibit cancer by targeting TAMs. Herein, we examined the effect of β-elemene on macrophages to elucidate a novel mechanism of β-elemene in tumor therapy. We showed that the conditioned medium of M2 macrophages promoted lung cancer cells to migration, invasion and epithelial mesenchymal transition, which could be inhibited by β-elemene. Moreover, β-elemene regulated the polarization of macrophages from M2 to M1. β-elemene also inhibited the proliferation, migration, invasion of lung cancer cells and enhanced its radiosensitivity. These results indicate β-elemene suppresses lung cancer by regulating both macrophages and lung cancer cells, it is a promising drug for combination with chemotherapy or radiotherapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Curcumin ameliorates macrophage infiltration by inhibiting NF-κB activation and proinflammatory cytokines in streptozotocin induced-diabetic nephropathy

    Directory of Open Access Journals (Sweden)

    Suzuki Kenji

    2011-06-01

    Full Text Available Abstract Background Chronic inflammation plays an important role in the progression of diabetic nephropathy (DN and that the infiltration of macrophages in glomerulus has been implicated in the development of glomerular injury. We hypothesized that the plant polyphenolic compound curcumin, which is known to exert potent anti-inflammatory effect, would ameliorate macrophage infiltration in streptozotocin (STZ-induced diabetic rats. Methods Diabetes was induced with STZ (55 mg/kg by intraperitoneal injection in rats. Three weeks after STZ injection, rats were divided into three groups, namely, control, diabetic, and diabetic treated with curcumin at 100 mg/kg/day, p.o., for 8 weeks. The rats were sacrificed 11 weeks after induction of diabetes. The excised kidney was used to assess macrophage infiltration and expression of various inflammatory markers. Results At 11 weeks after STZ injection, diabetic rats exhibited renal dysfunction, as evidenced by reduced creatinine clearance, increased blood glucose, blood urea nitrogen and proteinuria, along with marked reduction in the body weight. All of these abnormalities were significantly reversed by curcumin. Hyperglycemia induced the degradation of IκBα and NF-κB activation and as a result increased infiltration of macrophages (52% as well as increased proinflammatory cytokines: TNF-α and IL-1β. Curcumin treatment significantly reduced macrophage infiltration in the kidneys of diabetic rats, suppressed the expression of above proinflammatory cytokines and degradation of IκBα. In addition, curcumin treatment also markedly decreased ICAM-1, MCP-1 and TGF-β1 protein expression. Moreover, at nuclear level curcumin inhibited the NF-κB activity. Conclusion Our results suggested that curcumin treatment protect against the development of DN in rats by reducing macrophage infiltration through the inhibition of NF-κB activation in STZ-induced diabetic rats.

  4. Macrophages Polarized by Expression of ToxoGRA15II Inhibit Growth of Hepatic Carcinoma

    Science.gov (United States)

    Li, Yuanling; Poppoe, Faustina; Chen, Jian; Yu, Li; Deng, Fang; Luo, Qingli; Xu, Yuanhong; Cai, Yihong; Shen, Jilong

    2017-01-01

    A growing body of evidence suggests that tumor-associated macrophages are deeply involved in the hepatocellular carcinoma proliferation and account for the large proportion of infiltrated cells in tumor tissues and play a major role in promotion of tumor growth. On the other hand, studies have demonstrated that Toxoplasma gondii virulence-associated molecule of dense granule protein (ToxoGRA15II) tends to induce classically activated macrophages (M1) differentiation. Thus, we explored the M1 induced by ToxoGRA15II in vitro and its inhibitory impact on the proliferation, invasion, and metastasis of hepatic carcinoma in murine model. Here, we constructed recombinant plasmid of pegfp-gra15II and subsequently ligate it to lentivirus (Lv) vector, with which RAW264.7 was transfected. The results showed that the transfected macrophages were polarized to M1. Coculture of the M1 with Hepa1-6 cells showed a remarkable inhibition of migration and invasion of the tumor cells and decreased expressions of matrix metalloproteinase (MMP)-9 and MMP-2 without notable apoptosis of Hepa1-6 cells. Subsequently, ToxoGRA15II-polarized macrophages inoculated to tumor-bearing C57BL/6 mice were seen in both spleen and tumor tissues, and tumor growth was sharply restricted. Particularly, interleukin-6 (IL-6) expression, which is closely associated with the cancer malignant behaviors, was significantly dampened in tumor tissues. In addition, expression of TNF-α and IL-12 mRNAs was increased, whereas IL-6 and interleukin-10 mRNAs were downregulated in splenocytes. Our results indicate that the effector molecule of ToxoGRA15II may induce macrophage polarization to M1 that has a restrictive effect on tumor growth via its related cytokines profile in tumor and spleen tissues. Besides, ToxoGRA15II, due to its early activation of specified cell population and non-toxicity to mammalians, has a potential value for a novel therapeutic strategy of enhancing host innate immunity against tumor

  5. Modeling Synergistic Drug Inhibition of Mycobacterium tuberculosis Growth in Murine Macrophages

    Science.gov (United States)

    2011-01-01

    synergistic drug inhibition of Mycobacterium tuberculosis growth in murine macrophagesw Xin Fang, Anders Wallqvist and Jaques Reifman* Received 15th...inhibition of Mycobacterium tuberculosis in murine macrophage cells. We used it to simulate ex vivo bacterial growth inhibition due to 3-nitropropionate (3...is felt worldwide, with 9.4 million new cases and 1.8 million deaths in 2008.1,2 The causative agent of the disease, Mycobacterium tuberculosis

  6. Inhibition of autophagy ameliorates atherogenic inflammation by augmenting apigenin-induced macrophage apoptosis.

    Science.gov (United States)

    Wang, Qun; Zeng, Ping; Liu, Yuanliang; Wen, Ge; Fu, Xiuqiong; Sun, Xuegang

    2015-07-01

    Increasing evidences showed that the survival of macrophages promotes atherogenesis. Macrophage apoptosis in the early phase of atherosclerotic process negatively regulates the progression of atherosclerotic lesions. We demonstrated that a natural anti-oxidant apigenin could ameliorate atherogenesis in ApoE(-/-) mice. It reduced the number of foam cells and decreased the serum levels of tumor necrosis factor α, interleukin 1β (IL-1β) and IL-6. Our results showed that oxidized low-density lipoprotein (oxLDL) led to the secretion of pro-inflammatory cytokines. Apigenin-induced apoptosis and downregulated the secretion of TNF-α, IL-6 and IL-1β. It is further supported by the use of zVAD, a pan-caspase inhibitor, demonstrating that apigenin lowered cytokine profile through induction of macrophage apoptosis. Moreover, apigenin-induced Atg5/Atg7-dependent autophagy in macrophages pretreated with oxLDL. Results illustrated that autophagy inhibition increased apigenin-induced apoptosis through activation of Bax. The present findings suggest that oxLDL maintained the survival of macrophages and activated the secretion of pro-inflammatory cytokines to initiate atherosclerosis. Apigenin-induced apoptosis of lipid-laden macrophages and resolved inflammation to ameliorate atherosclerosis. In conclusion, combination of apigenin with autophagy inhibition may be a promising strategy to induce foam cell apoptosis and subdue atherogenic cytokines.

  7. Activation of Phosphotyrosine Phosphatase Activity Attenuates Mitogen-Activated Protein Kinase Signaling and Inhibits c-FOS and Nitric Oxide Synthase Expression in Macrophages Infected with Leishmania donovani

    OpenAIRE

    Nandan, Devki; Lo, Raymond; Reiner, Neil E

    1999-01-01

    Intracellular protozoan parasites of the genus Leishmania antagonize host defense mechanisms by interfering with cell signaling in macrophages. In this report, the impact of Leishmania donovani on mitogen-activated protein (MAP) kinases and nitric oxide synthase (NOS) expression in the macrophage cell line RAW 264 was investigated. Overnight infection of cells with leishmania led to a significant decrease in phorbol-12-myristate-13-acetate (PMA)-stimulated MAP kinase activity and inhibited PM...

  8. Anti-WASP intrabodies inhibit inflammatory responses induced by Toll-like receptors 3, 7, and 9, in macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Sakuma, Chisato [Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, 1-2 Ohwashi, Tsukuba, Ibaraki, 305-8634 (Japan); Sato, Mitsuru, E-mail: mitsuru.sato@affrc.go.jp [Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, 1-2 Ohwashi, Tsukuba, Ibaraki, 305-8634 (Japan); Oshima, Takuma [Department of Biological Science and Technology, Graduate School of Faculty of Industrial Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510 (Japan); Takenouchi, Takato [Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, 1-2 Ohwashi, Tsukuba, Ibaraki, 305-8634 (Japan); Chiba, Joe [Department of Biological Science and Technology, Graduate School of Faculty of Industrial Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba, 278-8510 (Japan); Kitani, Hiroshi [Animal Immune and Cell Biology Research Unit, National Institute of Agrobiological Sciences, 1-2 Ohwashi, Tsukuba, Ibaraki, 305-8634 (Japan)

    2015-02-27

    Wiskott-Aldrich syndrome protein (WASP) is an adaptor molecule in immune cells. Recently, we showed that the WASP N-terminal domain interacted with the SH3 domain of Bruton's tyrosine kinase (Btk), and that the complex formed by WASP and Btk was important for TLR2 and TLR4 signaling in macrophages. Several other studies have shown that Btk played important roles in modulating innate immune responses through TLRs in immune cells. Here, we evaluated the significance of the interaction between WASP and Btk in TLR3, TLR7, and TLR9 signaling. We established bone marrow–derived macrophage cell lines from transgenic (Tg) mice that expressed intracellular antibodies (intrabodies) that specifically targeted the WASP N-terminal domain. One intrabody comprised the single-chain variable fragment and the other comprised the light-chain variable region single domain of an anti-WASP N-terminal monoclonal antibody. Both intrabodies inhibited the specific interaction between WASP and Btk, which impaired the expression of TNF-α, IL-6, and IL-1β in response to TLR3, TLR7, or TLR9 stimulation. Furthermore, the intrabodies inhibited the phosphorylation of both nuclear factor (NF)-κB and WASP in response to TLR3, TLR7, or TLR9 stimulation, in the Tg bone marrow-derived macrophages. These results suggested that WASP plays important roles in TLR3, TLR7, and TLR9 signaling by associating with Btk in macrophages. - Highlights: • The interaction between WASP and Btk is critical for TLR3, TLR7, and TLR9 signaling. • Anti-WASP intrabodies inhibited several TLR pathways that led to cytokine expression. • Phosphorylation of NF-κB via TLR signaling was inhibited by anti-WASP intrabodies. • WASP phosphorylation via several TLR ligands was inhibited by anti-WASP intrabodies.

  9. Dopamine induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages in rat C6 glioma

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Tian; Wang, Chenlong; Chen, Xuewei; Duan, Chenfan; Zhang, Xiaoyan [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Zhang, Jing [Animal Experimental Center of Wuhan University, Wuhan 430071 (China); Chai, Hongyan [Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan 430071 (China); Tang, Tian [Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Chen, Honglei [Department of Pathology and Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yue, Jiang [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Li, Ying, E-mail: lyying0@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

    2015-07-15

    Dopamine (DA), a monoamine catecholamine neurotransmitter with antiangiogenic activity, stabilizes tumor vessels in colon, prostate and ovarian cancers, thus increases chemotherapeutic efficacy. Here, in the rat C6 glioma models, we investigated the vascular normalization effects of DA and its mechanisms of action. DA (25, 50 mg/kg) inhibited tumor growth, while a precursor of DA (levodopa) prolonged the survival time of rats bearing orthotopic C6 glioma. DA improved tumor perfusion, with significant effects from day 3, and a higher level at days 5 to 7. In addition, DA decreased microvessel density and hypoxia-inducible factor-1α expression in tumor tissues, while increasing the coverage of pericyte. Conversely, an antagonist of dopamine receptor 2 (DR2) (eticlopride) but not DR1 (butaclamol) abrogated DA-induced tumor regression and vascular normalization. Furthermore, DA improved the delivery and efficacy of temozolomide therapy. Importantly, DA increased representative M1 markers (iNOS, CXCL9, etc.), while decreasing M2 markers (CD206, arginase-1, etc.). Depletion of macrophages by clodronate or zoledronic acid attenuated the effects of DA. Notably, DA treatment induced M2-to-M1 polarization in RAW264.7 cells and mouse peritoneal macrophages, and enhanced the migration of pericyte-like cells (10T1/2), which was reversed by eticlopride or DR2-siRNA. Such changes were accompanied by the downregulation of VEGF/VEGFR2 signaling. In summary, DA induces growth inhibition and vascular normalization through reprogramming M2-polarized macrophages. Thus, targeting the tumor microvasculature by DA represents a promising strategy for human glioma therapy. - Highlights: • Dopamine induces tumor growth inhibition and vascular normalization in rat C6 glioma. • Dopamine switches macrophage phenotype from M2 to M1. • Dopamine-induced vascular normalization is mediated by macrophage polarization. • Dopamine is a promising agent targeting the microvasculature in tumor

  10. Sargachromenol from Sargassum micracanthum Inhibits the Lipopolysaccharide-Induced Production of Inflammatory Mediators in RAW 264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Eun-Jin Yang

    2013-01-01

    Full Text Available During our ongoing screening program designed to determine the anti-inflammatory potential of natural compounds, we isolated sargachromenol from Sargassum micracanthum. In the present study, we investigated the anti-inflammatory effects of sargachromenol on lipopolysaccharide (LPS-induced inflammation in murine RAW 264.7 macrophage cells and the underlying mechanisms. Sargachromenol significantly inhibited the LPS-induced production of nitric oxide (NO and prostaglandin E2 (PGE2 in a dose-dependent manner. It also significantly inhibited the protein expression of inducible NO synthase (iNOS and cyclooxygenase-2 (COX-2 in a dose-dependent manner in LPS-stimulated macrophage cells. Further analyses showed that sargachromenol decreased the cytoplasmic loss of inhibitor κBα (IκBα protein. These results suggest that sargachromenol may exert its anti-inflammatory effects on LPS-stimulated macrophage cells by inhibiting the activation of the NF-κB signaling pathway. In conclusion, to our knowledge, this is the first study to show that sargachromenol isolated from S. micracanthum has an effective anti-inflammatory activity. Therefore, sargachromenol might be useful for cosmetic, food, or medical applications requiring anti-inflammatory properties.

  11. Selective inhibition of PI3K/Akt/mTOR signaling pathway regulates autophagy of macrophage and vulnerability of atherosclerotic plaque.

    Directory of Open Access Journals (Sweden)

    Chungang Zhai

    Full Text Available Macrophage infiltration contributes to the instability of atherosclerotic plaques. In the present study, we investigated whether selective inhibition of PI3K/Akt/mTOR signaling pathway can enhance the stability of atherosclerotic plaques by activation of macrophage autophagy. In vitro study, selective inhibitors or siRNA of PI3K/Akt/mTOR pathways were used to treat the rabbit's peritoneal primary macrophage cells. Inflammation related cytokines secreted by macrophages were measured. Ultrastructure changes of macrophages were examined by transmission electron microscope. mRNA or protein expression levels of autophagy related gene Beclin 1, protein 1 light chain 3 II dots (LC3-II or Atg5-Atg12 conjugation were assayed by quantitative RT-PCR or Western blot. In vivo study, vulnerable plaque models were established in 40 New Zealand White rabbits and then drugs or siRNA were given for 8 weeks to inhibit the PI3K/Akt/mTOR signaling pathway. Intravascular ultrasound (IVUS was performed to observe the plaque imaging. The ultrastructure of the abdominal aortic atherosclerosis lesions were analyzed with histopathology. RT-PCR or Western blot methods were used to measure the expression levels of corresponding autophagy related molecules. We found that macrophage autophagy was induced in the presence of Akt inhibitor, mTOR inhibitor and mTOR-siRNA in vitro study, while PI3K inhibitor had the opposite role. In vivo study, we found that macrophage autophagy increased significantly and the rabbits had lower plaque rupture incidence, lower plaque burden and decreased vulnerability index in the inhibitors or siRNA treated groups. We made a conclusion that selective inhibition of the Akt/mTOR signal pathway can reduce macrophages and stabilize the vulnerable atherosclerotic plaques by promoting macrophage autophagy.

  12. Aspirin Modulates Innate Inflammatory Response and Inhibits the Entry of Trypanosoma cruzi in Mouse Peritoneal Macrophages

    Directory of Open Access Journals (Sweden)

    Aparecida Donizette Malvezi

    2014-01-01

    Full Text Available The intracellular protozoan parasite Trypanosoma cruzi causes Chagas disease, a serious disorder that affects millions of people in Latin America. Cell invasion by T. cruzi and its intracellular replication are essential to the parasite’s life cycle and for the development of Chagas disease. Here, we present evidence suggesting the involvement of the host’s cyclooxygenase (COX enzyme during T. cruzi invasion. Pharmacological antagonist for COX-1, aspirin (ASA, caused marked inhibition of T. cruzi infection when peritoneal macrophages were pretreated with ASA for 30 min at 37°C before inoculation. This inhibition was associated with increased production of IL-1β and nitric oxide (NO∙ by macrophages. The treatment of macrophages with either NOS inhibitors or prostaglandin E2 (PGE2 restored the invasive action of T. cruzi in macrophages previously treated with ASA. Lipoxin ALX-receptor antagonist Boc2 reversed the inhibitory effect of ASA on trypomastigote invasion. Our results indicate that PGE2, NO∙, and lipoxins are involved in the regulation of anti-T. cruzi activity by macrophages, providing a better understanding of the role of prostaglandins in innate inflammatory response to T. cruzi infection as well as adding a new perspective to specific immune interventions.

  13. Inhibition of ecto-ATPase activities impairs HIV-1 infection of macrophages.

    Science.gov (United States)

    Schachter, Julieta; Delgado, Kelly Valcárcel; Barreto-de-Souza, Victor; Bou-Habib, Dumith Chequer; Persechini, Pedro Muanis; Meyer-Fernandes, José Roberto

    2015-05-01

    Nucleotides and nucleosides are secreted into extracellular media at different concentrations as a consequence of different physiologic and pathological conditions. Ecto-nucleotidases, enzymes present on the surface of most cells, hydrolyze these extracellular nucleotides and reduce the concentration of them, thus affecting the activation of different nucleotide and nucleoside receptors. Also, ecto-nucleotidases are present in a number of microorganisms and play important roles in host-pathogen interactions. Here, we characterized the ecto-ATPase activities present on the surface of HIV-1 particle and human macrophages as well. We found that the kinetic properties of HIV-1 and macrophage ecto-ATPases are similar, suggesting that the enzyme is the same. This ecto-ATPase activity was increased in macrophages infected in vitro with HIV-1. Using three different non-related ecto-ATPase inhibitors-POM-1, ARL67156 and BG0-we showed that the inhibition of these macrophage and viral ecto-ATPase activities impairs HIV-1 infection. In addition, we also found that elevated extracellular concentrations of ATP inhibit HIV-1 production by infected macrophages. Copyright © 2014 Elsevier GmbH. All rights reserved.

  14. The clinical significance of the CD163+ and CD68+ macrophages in patients with hepatocellular carcinoma.

    Science.gov (United States)

    Kong, Ling-Qun; Zhu, Xiao-Dong; Xu, Hua-Xiang; Zhang, Ju-Bo; Lu, Lu; Wang, Wen-Quan; Zhang, Qiang-Bo; Wu, Wei-Zhong; Wang, Lu; Fan, Jia; Tang, Zhao-You; Sun, Hui-Chuan

    2013-01-01

    Our previous study has found that the abundance of peritumoral CD68(+) macrophages was associated with poor prognosis in hepatocellular carcinoma (HCC) after resection. However, CD68 staining could not discriminate the protumoral or tumoricidal subpopulations from pan-macrophages. CD163 is a marker of alternatively activated macrophages. In this study, the clinical significance of CD163(+) cells in tumors and peritumoral liver tissues was evaluated in a cohort of 295 patients with HCC after curative resection. We found that the density of CD163(+) cells was well correlated with that of CD68(+) cells in both tumors and peritumoral liver tissues but was much more. Immunostaining on consecutive sections and flow cytometry assay on surgical resected specimens further supported the findings that the CD163(+) cells was more abundant than CD68(+) cells. The density of peritumoral CD68(+) cells was associated with poor recurrence-free survival (RFS) and poor overall survival (OS) (P = 0.004 and P = 0.001, respectively), whereas the CD163(+) cells have no prognostic values either in tumors or in peritumoral liver tissues. In another cohort of 107 HCC patients, preoperative plasma concentration of soluble form of CD163 (sCD163) was associated with active hepatitis-related factors but not associated with the markers of tumor invasion. In conclusion, both the CD163(+) cells local infiltration and plasma sCD163 were of limited significance in HCC, and they were more likely markers related to active hepatitis rather than tumor progression.

  15. Arctigenin ameliorates inflammation in vitro and in vivo by inhibiting the PI3K/AKT pathway and polarizing M1 macrophages to M2-like macrophages.

    Science.gov (United States)

    Hyam, Supriya R; Lee, In-Ah; Gu, Wan; Kim, Kyung-Ah; Jeong, Jin-Ju; Jang, Se-Eun; Han, Myung Joo; Kim, Dong-Hyun

    2013-05-15

    Seeds of Arctium lappa, containing arctigenin and its glycoside arctiin as main constituents, have been used as a diuretic, anti-inflammatory and detoxifying agent in Chinese traditional medicine. In our preliminary study, arctigenin inhibited IKKβ and NF-κB activation in peptidoglycan (PGN)- or lipopolysaccharide (LPS)-induced peritoneal macrophages. To understand the anti-inflammatory effect of arctigenin, we investigated its anti-inflammatory effect in LPS-stimulated peritoneal macrophages and on LPS-induced systemic inflammation as well as 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. Arctigenin inhibited LPS-increased IL-1β, IL-6 and TNF-α expression in LPS-stimulated peritoneal macrophages, but increased LPS-reduced IL-10 and CD204 expression. Arctigenin inhibited LPS-induced PI3K, AKT and IKKβ phosphorylation, but did not suppress LPS-induced IRAK-1 phosphorylation. However, arctigenin did not inhibit NF-κB activation in LPS-stimulated PI3K siRNA-treated peritoneal macrophages. Arctigenin suppressed the binding of p-PI3K antibody and the nucleus translocation of NF-κB p65 in LPS-stimulated peritoneal macrophages. Arctigenin suppressed blood IL-1β and TNF-α level in mice systemically inflamed by intraperitoneal injection of LPS. Arctigenin also inhibited colon shortening, macroscopic scores and myeloperoxidase activity in TNBS-induced colitic mice. Arctigenin inhibited TNBS-induced IL-1β, TNF-α and IL-6 expression, as well as PI3K, AKT and IKKβ phosphorylation and NF-κB activation in mice, but increased IL-10 and CD204 expression. However, it did not affect IRAK-1 phosphorylation. Based on these findings, arctigenin may ameliorate inflammatory diseases, such as colitis, by inhibiting PI3K and polarizing M1 macrophages to M2-like macrophages.

  16. IL-17A promotes intracellular growth of Mycobacterium by inhibiting apoptosis of infected macrophages

    Directory of Open Access Journals (Sweden)

    Andrea eCruz

    2015-09-01

    Full Text Available The fate of infected macrophages is a critical aspect of immunity to mycobacteria. By depriving the pathogen of its intracellular niche, apoptotic death of the infected macrophage has been shown to be an important mechanism to control bacterial growth. Here we show that IL-17 inhibits apoptosis of Mycobacterium bovis BCG- or M. tuberculosis-infected macrophages thus hampering their ability to control bacterial growth. Mechanistically, we show that IL-17 inhibits p53, and impacts on the intrinsic apoptotic pathway, by increasing the Bcl2 and decreasing Bax expression, decreasing cytochrome c release from the mitochondria, and inhibiting caspase-3 activation. The same effect of IL-17 was observed in infected macrophages upon blockade of p53 nuclear translocation. These results reveal a previously unappreciated role for the IL-17/p53 axis in the regulation of mycobacteria-induced apoptosis and can have important implications in a broad spectrum of diseases where apoptosis of the infected cell is an important host defense mechanism. .

  17. Activation of TLR3/interferon signaling pathway by bluetongue virus results in HIV inhibition in macrophages.

    Science.gov (United States)

    Dai, Ming; Wang, Xu; Li, Jie-Liang; Zhou, Yu; Sang, Ming; Liu, Jin-Biao; Wu, Jian-Guo; Ho, Wen-Zhe

    2015-12-01

    Bluetongue virus (BTV), a nonenveloped double-stranded RNA virus, is a potent inducer of type Ι interferons in multiple cell systems. In this study, we report that BTV16 treatment of primary human macrophages induced both type I and III IFN expression, resulting in the production of multiple antiviral factors, including myxovirus resistance protein A, 2',5'-oligoadenylate synthetase, and the IFN-stimulated gene 56. Additionally, BTV-treated macrophages expressed increased HIV restriction factors (apolipoprotein B mRNA-editing enzyme catalytic polypeptide 3 G/F/H) and CC chemokines (macrophage inflammatory protein 1-α, macrophage inflammatory protein 1-β, regulated on activation of normal T cell expressed and secreted), the ligands for HIV entry coreceptor CC chemokine receptor type 5. BTV16 also induced the expression of tetherin, which restricts HIV release from infected cells. Furthermore, TLR3 signaling of macrophages by BTV16 resulted in the induction of several anti-HIV microRNAs (miRNA-28, -29a, -125b, -150, -223, and -382). More importantly, the induction of antiviral responses by BTV resulted in significant suppression of HIV in macrophages. These findings demonstrate the potential of BTV-mediated TLR3 activation in macrophage innate immunity against HIV.

  18. IFN-λ Inhibits Drug-Resistant HIV Infection of Macrophages

    Science.gov (United States)

    Wang, Xu; Wang, He; Liu, Man-Qing; Li, Jie-Liang; Zhou, Run-Hong; Zhou, Yu; Wang, Yi-Zhong; Zhou, Wang; Ho, Wen-Zhe

    2017-01-01

    Type III interferons (IFN-λs) have been demonstrated to inhibit a number of viruses, including HIV. Here, we further examined the anti-HIV effect of IFN-λs in macrophages. We found that IFN-λs synergistically enhanced anti-HIV activity of antiretrovirals [azidothymidine (AZT), efavirenz, indinavir, and enfuvirtide] in infected macrophages. Importantly, IFN-λs could suppress HIV infection of macrophages with the drug-resistant strains, including AZT-resistant virus (A012) and reverse transcriptase inhibitor-resistant virus (TC49). Mechanistically, IFN-λs were able to induce the expression of several important anti-HIV cellular factors, including myxovirus resistance 2 (Mx2), a newly identified HIV post-entry inhibitor and tetherin, a restriction factor that blocks HIV release from infected cells. These observations provide additional evidence to support the potential use of IFN-λs as therapeutics agents for the treatment of HIV infection. PMID:28321215

  19. Inhibition of CDKS by roscovitine suppressed LPS-induced ·NO production through inhibiting NFκB activation and BH4 biosynthesis in macrophages

    Science.gov (United States)

    Wei, Na; Guan, Tongju; Xu, Hao; An, Jianzhong; Pritchard, Kirkwood A.

    2009-01-01

    In inflammatory diseases, tissue damage is critically associated with nitric oxide (·NO) and cytokines, which are overproduced in response to cellular release of endotoxins. Here we investigated the inhibitory effect of roscovitine, a selective inhibitor of cyclin-dependent kinases (CDKs) on ·NO production in mouse macrophages. In RAW264.7 cells, we found that roscovitine abolished the production of ·NO induced by lipopolysaccharide (LPS). Moreover, roscovitine significantly inhibited LPS-induced inducible nitric oxide synthase (iNOS) mRNA and protein expression. Our data also showed that roscovitine attenuated LPS-induced phosphorylation of IκB kinase β (IKKβ), IκB, and p65 but enhanced the phosphorylation of ERK, p38, and c-Jun NH2-terminal kinase (JNK). In addition, roscovitine dose dependently inhibited LPS-induced expression of cyclooxygenase-2 (COX)-2, IL-1β, and IL-6 but not tumor necrosis factor (TNF)-α. Tetrahydrobiopterin (BH4), an essential cofactor for iNOS, is easily oxidized to 7,8-dihydrobiopterin (BH2). Roscovitine significantly inhibited LPS-induced BH4 biosynthesis and decreased BH4-to-BH2 ratio. Furthermore, roscovitine greatly reduced the upregulation of GTP cyclohydrolase-1 (GCH-1), the rate-limiting enzyme for BH4 biosynthesis. Using other CDK inhibitors, we found that CDK1, CDK5, and CDK7, but not CDK2, significantly inhibited LPS-induced ·NO production in macrophages. Similarly, in isolated peritoneal macrophages, roscovitine strongly inhibited ·NO production, iNOS, and COX-2 upregulation, activation of NFκB, and induction of GCH-1 by LPS. Together, our data indicate that roscovitine abolishes LPS-induced ·NO production in macrophages by suppressing nuclear factor-κB activation and BH4 biosynthesis, which might be mediated by CDK1, CDK5, and CDK7. Our results also suggest that roscovitine may inhibit inflammation and that CDKs may play important roles in the mechanisms by which roscovitine attenuates inflammation. PMID:19553566

  20. Inhibition of inducible Nitric Oxide Synthase by a mustard gas analog in murine macrophages

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    Smith Milton

    2006-11-01

    Full Text Available Abstract Background 2-Chloroethyl ethyl sulphide (CEES is a sulphur vesicating agent and an analogue of the chemical warfare agent 2,2'-dichlorodiethyl sulphide, or sulphur mustard gas (HD. Both CEES and HD are alkylating agents that influence cellular thiols and are highly toxic. In a previous publication, we reported that lipopolysaccharide (LPS enhances the cytotoxicity of CEES in murine RAW264.7 macrophages. In the present investigation, we studied the influence of CEES on nitric oxide (NO production in LPS stimulated RAW264.7 cells since NO signalling affects inflammation, cell death, and wound healing. Murine macrophages stimulated with LPS produce NO almost exclusively via inducible nitric oxide synthase (iNOS activity. We suggest that the influence of CEES or HD on the cellular production of NO could play an important role in the pathophysiological responses of tissues to these toxicants. In particular, it is known that macrophage generated NO synthesised by iNOS plays a critical role in wound healing. Results We initially confirmed that in LPS stimulated RAW264.7 macrophages NO is exclusively generated by the iNOS form of nitric oxide synthase. CEES treatment inhibited the synthesis of NO (after 24 hours in viable LPS-stimulated RAW264.7 macrophages as measured by either nitrite secretion into the culture medium or the intracellular conversion of 4,5-diaminofluorescein diacetate (DAF-2DA or dichlorofluorescin diacetate (DCFH-DA. Western blots showed that CEES transiently decreased the expression of iNOS protein; however, treatment of active iNOS with CEES in vitro did not inhibit its enzymatic activity Conclusion CEES inhibits NO production in LPS stimulated macrophages by decreasing iNOS protein expression. Decreased iNOS expression is likely the result of CEES induced alteration in the nuclear factor kappa B (NF-κB signalling pathway. Since NO can act as an antioxidant, the CEES induced down-regulation of iNOS in LPS

  1. Isorhamnetin attenuates atherosclerosis by inhibiting macrophage apoptosis via PI3K/AKT activation and HO-1 induction.

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    Yun Luo

    Full Text Available Isorhamnetin (Iso is a flavonoid compound extracted from the Chinese herb Hippophae rhamnoides L. Previous studies have revealed its anti-cancer, anti-inflammatory, and anti-oxidant activities. This study investigated the ability of Iso to inhibit oxidized low-density lipoprotein (ox-LDL-induced cell apoptosis in THP-1-derived macrophages. The effects of Iso on atherosclerosis in vivo were also evaluated in apolipoprotein E knockout (ApoE-/- mice fed a high fat diet.Iso showed significant inhibitory effects on ox-LDL-induced THP-1-derived macrophage injuries via decreasing reactive oxygen species levels, lipid deposition, and caspase-3 activation, restoring mitochondrial membrane potential, reducing the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL-positive cells, and regulating apoptosis-related proteins. We also determined the protective effects of Iso by PI3K/AKT activation and HO-1 induction. Iso reduced the atherosclerotic plaque size in vivo in ApoE-/- mice as assessed by oil red O, Sudan IV staining, and CD68-positive cells, and reduced macrophage apoptosis as assessed by caspase-3 and TUNEL assays in lesions.In conclusion, our results show that Iso inhibited atherosclerotic plaque development in ApoE-/- mice by PI3K/AKT activation and HO-1 induction.

  2. Losartan inhibited expression of matrix metalloproteinases in rat atherosclerotic lesions and angiotensin Ⅱ-stimulated macrophages

    Institute of Scientific and Technical Information of China (English)

    ChunLIANG; Zong-guiWU; JianDING; Jian-feiJIANG; Gao-zhongHUANG; Rong-zengDU; Jun-boGE

    2004-01-01

    AIM: To explore whether the angiotensin Ⅱ (Ang Ⅱ) receptor 1 (ATI) antagonist, losartan could reduce activity and expression of matrix metalloproteinases (MMPs) in rat atherosclerotic plaques. METHODS: Male Wistar-Kyoto rats were ip injected a single dose of vitamin D3 600 kU·kg·-1·month-1 and fed an atherogenic diet for 4 months to induce experimental atheroma. Then either placebo or losartan 50 kU·kg·-1·d-1 was administered in rats for another 2 months. In vitro, the effect of losartan 0.1-10 μmol/L on the expression of MMP-2 and MMP-9 was investigated in Ang Ⅱ-stimulated rat peritoneal macrophages. The expression and activity of MMP-2 and MMP-9 were monitored by Western blot, RT-PCR, and SDS-PAGE zymography analysis. RESULTS: High levels of MMP-2 and MMP-9 were expressed in rat atherosclerotic lesions. Losartan significantly reduced the activity and expression of MMP-2 and MMP-9 compared with the placebo group (MMP-2, 5861±539 vs 8991±965, P<0.05; MMP-9,10527±1002 vs 14623±2462, P<0.01). In cultured rat peritoneal macrophages, Ang Ⅱ 0.1 μmol/L elicited an increase in MMP-2 and MMP-9 activity and expression that were prevented by losartan in a dose-dependent manner (P<0.01). But the AT2receptor antagonist PD123319 had no effect. CONCLUSION: Losartan reduced the expression and activity of MMP-2 and MMP-9 in rat atherosclerotic lesions. The anti-atherogenic effects of losartan were due to the direct inhibition of Ang Ⅱ bioactivity.

  3. Losartan inhibited expression of matrix metalloproteinases in rat atherosclerotic lesions and angiotensin Ⅱ-stimulated macrophages

    Institute of Scientific and Technical Information of China (English)

    Chun LIANG; Zong-gui WU; Jian DING; Jian-fei JIANG; Gao-zhong HUANG; Rong-zeng DU; Jun-bo GE

    2004-01-01

    AIM: To explore whether the angiotensin Ⅱ (Ang Ⅱ) receptor 1 (AT1) antagonist, losartan could reduce activity and expression of matrix metalloproteinases (MMPs) in rat atherosclerotic plaques. METHODS: Male Wistar-Kyoto induce experimental atheroma. Then either placebo or losartan 50 mg.kg-1.d-1 was administered in rats for another2 months. In vitro, the effect of losartan 0.1-10 μmol/L on the expression of MMP-2 and MMP-9 was investigated in Ang Ⅱ-stimulated rat peritoneal macrophages. The expression and activity of MMP-2 and MMP-9 were monitored by Western blot, RT-PCR, and SDS-PAGE zymography analysis. RESULTS: High levels of MMP-2 and MMP-9 were expressed in rat atherosclerotic lesions. Losartan significantly reduced the activity and expression of MMP-2 and MMP-9 compared with the placebo group (MMP-2, 5861±539 vs 8991±965, P<0.05; MMP-9,10527±1002 vs 14623±2462, P<0.01). In cultured rat peritoneal macrophages, Ang Ⅱ 0.1 μmol/L elicited an increase in MMP-2 and MMP-9 activity and expression that were prevented by losartan in a dose-dependent manner(P<0.01). But the AT2receptor antagonist PD123319 had no effect. CONCLUSION: Losartan reduced the expression and activity of MMP-2 and MMP-9 in rat atherosclerotic lesions. The anti-atherogenic effects of losartan were due to the direct inhibition of Ang Ⅱ bioactivity.

  4. Adenosine deaminase acting on RNA-1 (ADAR1 inhibits HIV-1 replication in human alveolar macrophages.

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    Michael D Weiden

    Full Text Available While exploring the effects of aerosol IFN-γ treatment in HIV-1/tuberculosis co-infected patients, we observed A to G mutations in HIV-1 envelope sequences derived from bronchoalveolar lavage (BAL of aerosol IFN-γ-treated patients and induction of adenosine deaminase acting on RNA 1 (ADAR1 in the BAL cells. IFN-γ induced ADAR1 expression in monocyte-derived macrophages (MDM but not T cells. ADAR1 siRNA knockdown induced HIV-1 expression in BAL cells of four HIV-1 infected patients on antiretroviral therapy. Similar results were obtained in MDM that were HIV-1 infected in vitro. Over-expression of ADAR1 in transformed macrophages inhibited HIV-1 viral replication but not viral transcription measured by nuclear run-on, suggesting that ADAR1 acts post-transcriptionally. The A to G hyper-mutation pattern observed in ADAR1 over-expressing cells in vitro was similar to that found in the lungs of HIV-1 infected patients treated with aerosol IFN-γ suggesting the model accurately represented alveolar macrophages. Together, these results indicate that ADAR1 restricts HIV-1 replication post-transcriptionally in macrophages harboring HIV-1 provirus. ADAR1 may therefore contribute to viral latency in macrophages.

  5. Sustained small interfering RNA-mediated human immunodeficiency virus type 1 inhibition in primary macrophages.

    Science.gov (United States)

    Song, Erwei; Lee, Sang-Kyung; Dykxhoorn, Derek M; Novina, Carl; Zhang, Dong; Crawford, Keith; Cerny, Jan; Sharp, Phillip A; Lieberman, Judy; Manjunath, N; Shankar, Premlata

    2003-07-01

    Small interfering RNAs (siRNAs) can induce potent gene silencing by degradation of cognate mRNA. However, in dividing cells, the silencing lasts only 3 to 7 days, presumably because of siRNA dilution with cell division. Here, we investigated if sustained siRNA-mediated silencing of human immunodeficiency virus type 1 (HIV-1) is possible in terminally differentiated macrophages, which constitute an important reservoir of HIV in vivo. CCR5, the major HIV-1 coreceptor in macrophages, and the viral structural gene for p24 were targeted either singly or in combination. When transfected 2 days prior to infection, both CCR5 and p24 siRNAs effectively reduced HIV-1 infection for the entire 15-day period of observation, and combined targeting of both genes abolished infection. To investigate whether exogenously introduced siRNA is maintained stably in macrophages, we tested the kinetics of siRNA-mediated viral inhibition by initiating infections at various times (2 to 15 days) after transfection with CCR5 and p24 siRNAs. HIV suppression mediated by viral p24 siRNA progressively decreased and was lost by day 7 posttransfection. In contrast, viral inhibition by cellular CCR5 knockdown was sustained even when transfection preceded infection by 15 days, suggesting that the continued presence of target RNA may be needed for persistence of siRNA. The longer sustenance of CCR5 relative to p24 siRNA in uninfected macrophages was also confirmed by detection of internalized siRNA by modified Northern blot analysis. We also tested the potential of p24 siRNA to stably silence HIV in the setting of an established infection where the viral target gene is actively transcribed. Under these circumstances, long-term suppression of HIV replication could be achieved with p24 siRNA. Thus, siRNAs can induce potent and long-lasting HIV inhibition in nondividing cells such as macrophages.

  6. A Novel Strategy for Inducing the Antitumor Effects of Triterpenoid Compounds: Blocking the Protumoral Functions of Tumor-Associated Macrophages via STAT3 Inhibition

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    Yukio Fujiwara

    2014-01-01

    Full Text Available There are many types of nontumor cells, including leukocytes, fibroblasts, and endothelial cells, in the tumor microenvironment. Among these cells, infiltrating macrophages have recently received attention as novel target cells due to their protumoral functions. Infiltrating macrophages are called tumor-associated macrophages (TAMs. TAMs polarized to the M2 phenotype are involved in tumor development and are associated with a poor clinical prognosis. Therefore, the regulation of TAM activation or M2 polarization is a new strategy for antitumor therapy. We screened natural compounds possessing an inhibitory effect on the M2 polarization of human macrophages. Among 200 purified natural compounds examined, corosolic acid (CA and oleanolic acid (OA, both are categorized in triterpenoid compounds, inhibited macrophage polarization to M2 phenotype by suppressing STAT3 activation. CA and OA also directly inhibited tumor cell proliferation and sensitized tumor cells to anticancer drugs, such as adriamycin and cisplatin. The in vivo experiments showed that CA significantly suppressed subcutaneous tumor development and lung metastasis in a murine sarcoma model. The application of triterpenoid compounds, such as CA and OA, is a potential new anticancer therapy targeting macrophage activation, with synergistic effects with anticancer agents.

  7. The clinical significance of the CD163+ and CD68+ macrophages in patients with hepatocellular carcinoma.

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    Ling-Qun Kong

    Full Text Available Our previous study has found that the abundance of peritumoral CD68(+ macrophages was associated with poor prognosis in hepatocellular carcinoma (HCC after resection. However, CD68 staining could not discriminate the protumoral or tumoricidal subpopulations from pan-macrophages. CD163 is a marker of alternatively activated macrophages. In this study, the clinical significance of CD163(+ cells in tumors and peritumoral liver tissues was evaluated in a cohort of 295 patients with HCC after curative resection. We found that the density of CD163(+ cells was well correlated with that of CD68(+ cells in both tumors and peritumoral liver tissues but was much more. Immunostaining on consecutive sections and flow cytometry assay on surgical resected specimens further supported the findings that the CD163(+ cells was more abundant than CD68(+ cells. The density of peritumoral CD68(+ cells was associated with poor recurrence-free survival (RFS and poor overall survival (OS (P = 0.004 and P = 0.001, respectively, whereas the CD163(+ cells have no prognostic values either in tumors or in peritumoral liver tissues. In another cohort of 107 HCC patients, preoperative plasma concentration of soluble form of CD163 (sCD163 was associated with active hepatitis-related factors but not associated with the markers of tumor invasion. In conclusion, both the CD163(+ cells local infiltration and plasma sCD163 were of limited significance in HCC, and they were more likely markers related to active hepatitis rather than tumor progression.

  8. A Commercial Preparation of Catalase Inhibits Nitric Oxide Production by Activated Murine Macrophages: Role of Arginase

    OpenAIRE

    Tian, Y.; Xing, Y.; Magliozzo, R.; Yu, K.; Bloom, B R; Chan, J

    2000-01-01

    Catalase is widely used as a pharmacological probe to evaluate the role of hydrogen peroxide in antimicrobial activities of phagocytic cells. This report demonstrates that the ability of a commercial preparation of catalase to inhibit concomitantly macrophage antimycobacterial activity and production of reactive nitrogen intermediates can be attributed, at least in part, to the depletion of l-arginine by contaminating arginase. In experimental systems that employ pharmacological probes, the e...

  9. LPS inhibits caspase 3-dependent apoptosis in RAW264.7 macrophages induced by the AMPK activator AICAR

    Energy Technology Data Exchange (ETDEWEB)

    Russe, Otto Quintus, E-mail: quintus@russe.eu; Möser, Christine V., E-mail: chmoeser@hotmail.com; Kynast, Katharina L., E-mail: katharina.kynast@googlemail.com; King, Tanya S., E-mail: tanya.sarah.king@googlemail.com; Olbrich, Katrin, E-mail: Katrin.olbrich@gmx.net; Grösch, Sabine, E-mail: groesch@em.uni-frankfurt.de; Geisslinger, Gerd, E-mail: geisslinger@em.uni-frankfurt.de; Niederberger, Ellen, E-mail: e.niederberger@em.uni-frankfurt.de

    2014-05-09

    Highlights: • AMPK-activation induces caspase 3-dependent apoptosis in macrophages. • Apoptosis is associated with decreased mTOR and increased p21 levels. • All effects can be significantly inhibited by the TLR4 agonist lipopolysaccharide. - Abstract: AMP-activated kinase is a cellular energy sensor which is activated in stages of increased ATP consumption. Its activation has been associated with a number of beneficial effects such as decreasing inflammatory processes and the disease progress of diabetes and obesity, respectively. Furthermore, AMPK activation has been linked with induction of cell cycle arrest and apoptosis in cancer and vascular cells, indicating that it might have a therapeutic impact for the treatment of cancer and atherosclerosis. However, the impact of AMPK on the proliferation of macrophages, which also play a key role in the formation of atherosclerotic plaques and in inflammatory processes, has not been focused so far. We have assessed the influence of AICAR- and metformin-induced AMPK activation on cell viability of macrophages with and without inflammatory stimulation, respectively. In cells without inflammatory stimulation, we found a strong induction of caspase 3-dependent apoptosis associated with decreased mTOR levels and increased expression of p21. Interestingly, these effects could be inhibited by co-stimulation with bacterial lipopolysaccharide (LPS) but not by other proinflammatory cytokines suggesting that AICAR induces apoptosis via AMPK in a TLR4-pathway dependent manner. In conclusion, our results revealed that AMPK activation is not only associated with positive effects but might also contribute to risk factors by disturbing important features of macrophages. The fact that LPS is able to restore AMPK-associated apoptosis might indicate an important role of TLR4 agonists in preventing unfavorable cell death of immune cells.

  10. Inhibition of Cholesterol Esterification Influences Cytokine Exspression in Lypopolisaccharide-activated P388D1 Macrophages

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    Rosa Rita Bonatesta

    2007-01-01

    Full Text Available Several in vivo and in vitro studies have demonstrated the involvement of infectious agents in the development of atherosclerosis. However, the mechanisms by which micro-organisms induce and/or aggravate atherosclerosis, are so far unclear. Accumulation of cholesterol esters and lipid laden cell formation are hallmark of the atherogenesis, however, the possible relationship between cholesterol esterification and the signal-transducing component of LPS recognition complex inducing cytokine secretion has not been yet investigated. In the present study, we investigated the effect of mevinolin, the ACAT inhibitor, Sandoz 58035, and plasma from statin-treated hypercholesterolemic patients on cholesterol metabolism and cytokine expression in LPS activated P388D1 macrophages. In P388D1 macrophages cholesterol synthesis and uptake, as well as cholesterol ester synthesis, were unchanged following LPS-activation. When cells were grown in presence of serum from patients under statin therapy, cholesterol esterification was lower compared to cells grown with plasma from healthy subjects, independently from the type of statin used. This effect was accompanied by inhibition of IL-1β expression in LPS activated cells. The ACAT inhibitor, Sandoz 58035, which completely blocked cholesterol esterification in normal and LPS-activated macrophages, prevented IL-1β and IL-6 over-expression in LPS activated cells. Although preliminary, these data point to a possible relationship between cholesterol esterification and cytokine production in macrophages, prospecting new possible mechanisms by which microbial or inflammatory agents may induce and/or accelerate the atherosclerotic process.

  11. Pharmacological inhibition of dynamin II reduces constitutive protein secretion from primary human macrophages.

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    Maaike Kockx

    Full Text Available Dynamins are fission proteins that mediate endocytic and exocytic membrane events and are pharmacological therapeutic targets. These studies investigate whether dynamin II regulates constitutive protein secretion and show for the first time that pharmacological inhibition of dynamin decreases secretion of apolipoprotein E (apoE and several other proteins constitutively secreted from primary human macrophages. Inhibitors that target recruitment of dynamin to membranes (MiTMABs or directly target the GTPase domain (Dyngo or Dynole series, dose- and time- dependently reduced the secretion of apoE. SiRNA oligo's targeting all isoforms of dynamin II confirmed the involvement of dynamin II in apoE secretion. Inhibition of secretion was not mediated via effects on mRNA or protein synthesis. 2D-gel electrophoresis showed that inhibition occurred after apoE was processed and glycosylated in the Golgi and live cell imaging showed that inhibited secretion was associated with reduced post-Golgi movement of apoE-GFP-containing vesicles. The effect was not restricted to macrophages, and was not mediated by the effects of the inhibitors on microtubules. Inhibition of dynamin also altered the constitutive secretion of other proteins, decreasing the secretion of fibronectin, matrix metalloproteinase 9, Chitinase-3-like protein 1 and lysozyme but unexpectedly increasing the secretion of the inflammatory mediator cyclophilin A. We conclude that pharmacological inhibitors of dynamin II modulate the constitutive secretion of macrophage apoE as a class effect, and that their capacity to modulate protein secretion may affect a range of biological processes.

  12. Ethanol extract of Justicia gendarussa inhibits lipopolysaccharide stimulated nitric oxide and matrix metalloproteinase-9 expression in murine macrophage.

    Science.gov (United States)

    Varma, R Sandeep; Ashok, G; Vidyashankar, S; Patki, P; Nandakumar, Krishna S

    2011-06-01

    Justicia gendarussa Burm (Acanthaceae) is a plant used to treat inflammatory diseases such as rheumatoid arthritis. However, the mechanism involved in the anti-inflammatory properties of this plant has not been studied well. The in vitro anti-inflammatory activities of ethanol extract of Justicia gendarussa leaves (J-01) are studied here for the first time. The ethanol extract, J-01 was prepared from the leaves of Justicia gendarussa. The inhibitory effect of J-01 in nitric oxide (NO) production, inducible nitric oxide synthase (iNOS) and matrix metalloproteinase-9 (MMP-9) gene expressions were studied in lipopolysaccharide (LPS) stimulated macrophage cell line RAW 264.7. J-01 in a concentration dependent manner (200-50 μg/mL) attenuated NO production from macrophage stimulated with LPS (1 μg/mL). Further, J-01 significantly suppressed iNOS mRNA expression in these cells. J-01 has also downregulated the MMP-9 gene expression in LPS stimulated macrophage. The modulatory function of J-01 in inhibiting NO, iNOS, and MMP-9 as obtained from the present in vitro studies provide first scientific evidence to support the anti-inflammatory properties of Justicia gendarussa. This plant may have potential use in the management of inflammatory conditions such as arthritis.

  13. Aspirin inhibits LPS-induced macrophage activation via the NF-κB pathway.

    Science.gov (United States)

    Liu, Yitong; Fang, Silian; Li, Xiaoyan; Feng, Jie; Du, Juan; Guo, Lijia; Su, Yingying; Zhou, Jian; Ding, Gang; Bai, Yuxing; Wang, Songling; Wang, Hao; Liu, Yi

    2017-09-14

    Aspirin (acetylsalicylic acid, ASA) has been shown to improve bone marrow mesenchymal stem cell-based calvarial bone regeneration by promoting osteogenesis and inhibiting osteoclastogenesis. However, it remains unknown whether aspirin influences other immune cells during bone formation. In the present study, we investigated whether ASA treatment influenced macrophage activation during the LPS inducement. We found that ASA could downregulate the expressions of iNOS and TNF-α both in mouse peritoneum macrophages and RAW264.7 cells induced by LPS via the IκK/IκB/NF-κB pathway and a COX2/PGE2/EP2/NF-κB feedback loop, without affecting the expressions of FIZZ/YM-1/ARG1 induced by IL-4. Furthermore, we created a rat mandibular bone defect model and showed that ASA treatment improved bone regeneration by inhibiting LPS-induced macrophage activation in the early stages of inflammation. Taken together, our results indicated that ASA treatment was a feasible strategy for improving bone regeneration, particularly in inflammatory conditions.

  14. Pioglitazone Suppresses CXCR7 Expression To Inhibit Human Macrophage Chemotaxis through Peroxisome Proliferator-Activated Receptor γ.

    Science.gov (United States)

    Zhao, Duo; Zhu, Zhicheng; Li, Dan; Xu, Rihao; Wang, Tiance; Liu, Kexiang

    2015-11-17

    Cardiovascular disease is the leading cause of morbidity and mortality in patients with type 2 diabetes mellitus (T2DM). Pioglitazone, the widely used thiazolidinedione, is shown to be efficient in the prevention of cardiovascular complications of T2DM. In this study, we report that pioglitazone inhibits CXCR7 expression and thus blocks chemotaxis in differentiated macrophage without perturbing cell viability or macrophage differentiation. In addition, pioglitazone-mediated CXCR7 suppression and chemotaxis inhibition occur via activating peroxisome proliferator-activated receptor γ (PPARγ) but not PPARα in differentiated macrophage. More importantly, pioglitazone therapy-induced PPARγ activation suppresses CXCR7 expression in human carotid atherosclerotic lesions. Collectively, our data demonstrate that pioglitazone suppresses CXCR7 expression to inhibit human macrophage chemotaxis through PPARγ.

  15. Leukocyte TLR5 deficiency inhibits atherosclerosis by reduced macrophage recruitment and defective T-cell responsiveness

    Science.gov (United States)

    Ellenbroek, Guilielmus H.J.M.; van Puijvelde, Gijs H.M.; Anas, Adam A.; Bot, Martine; Asbach, Miriam; Schoneveld, Arjan; van Santbrink, Peter J.; Foks, Amanda C.; Timmers, Leo; Doevendans, Pieter A.; Pasterkamp, Gerard; Hoefer, Imo E.; van der Poll, Tom; Kuiper, Johan; de Jager, Saskia C.A.

    2017-01-01

    Toll-like receptors (TLR) provide a critical link between innate and adaptive immunity, both important players in atherosclerosis. Since evidence for the role of TLR5 is lacking, we aimed to establish this in the immune axis of atherosclerosis. We assessed the effect of the TLR5-specific ligand Flagellin on macrophage maturation and T-cell polarisation. Next, we generated TLR5−/−LDLr−/− chimeras to study the effect of hematopoietic TLR5 deficiency on atherosclerosis formation. Flagellin stimulation did not influence wildtype or TLR5−/− macrophage maturation. Only in wildtype macrophages, Flagellin exposure increased MCP-1 and IL6 expression. Flagellin alone reduced T-helper 1 proliferation, which was completely overruled in the presence of T-cell receptor activation. In vivo, hematopoietic TLR5 deficiency attenuated atherosclerotic lesion formation by ≈25% (1030*103 ± 63*103 vs. 792*103 ± 61*103 μm2; p = 0.013) and decreased macrophage area (81.3 ± 12.0 vs. 44.2 ± 6.6 μm2; p = 0.011). In TLR5−/− chimeric mice, we observed lower IL6 plasma levels (36.4 ± 5.6 vs. 15.1 ± 2.2 pg/mL; p = 0.003), lower (activated) splenic CD4+ T-cell content (32.3 ± 2.1 vs. 21.0 ± 1.2%; p = 0.0018), accompanied by impaired T-cell proliferative responses. In conclusion, hematopoietic TLR5 deficiency inhibits atherosclerotic lesion formation by attenuated macrophage accumulation and defective T-cell responsiveness. PMID:28202909

  16. Receptor interacting protein kinase-2 inhibition by CYLD impairs anti-bacterial immune responses in macrophages

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    Katharina eWex

    2016-01-01

    Full Text Available Upon infection with intracellular bacteria, nucleotide oligomerization domain protein 2 (NOD2 recognizes bacterial muramyl dipeptide and binds, subsequently, to receptor-interacting serine/threonine kinase 2 (RIPK2. RIPK2 mediates the activation of immune responses via the nuclear factor-κB (NF-κB and extracellular-signal regulated kinase (ERK pathways. Previously, it has been shown that RIPK2 activation dependens on its K63-ubiquitination by the E3 ligases pellino-3 and ITCH, whereas the deubiquitinating enzyme A20 counter-regulates RIPK2 activity by cleaving K63-polyubiquitin chains from RIPK2. Here, we newly identify the deubiquitinating enzyme CYLD as a new interacting partner and inhibitor of RIPK2. We show that CYLD binds to and removes K63-polyubiquitin chains from RIPK2 in Listeria monocytogenes (Lm infected bone-marrow-derived macrophages (BMDM. CYLD-mediated K63-deubiquitination of RIPK2 resulted in an impaired activation of both NF-κB and ERK1/2 pathways, reduced production of proinflammatory cytokines (IL-6, IL-12, anti-listerial ROS and NO, and, finally, impaired pathogen control. In turn, RIPK2 inhibition by siRNA prevented activation of NF-κB and ERK1/2 and completely abolished the protective effect of CYLD-deficiency with respect to the production of IL-6, NO, ROS and pathogen control. Noteworthy, CYLD also inhibited autophagy of Listeria in a RIPK2-ERK1/2 dependent manner.The protective function of CYLD-deficiency was dependent on IFN-γ pre-stimulation of infected macrophages. Interestingly, the reduced NF-κB activation in CYLD-expressing macrophages limited the protective effect of IFN-γ by reducing NF-κB-dependent STAT1 activation. Taken together, our study identifies CYLD as an important inhibitor of RIPK2-dependent anti-bacterial immune responses in macrophages.

  17. Tea polyphenols inhibit the activation of NF-κB and the secretion of cytokines and matrix metalloproteinases by macrophages stimulated with Fusobacterium nucleatum

    Science.gov (United States)

    Lagha, Amel Ben; Grenier, Daniel

    2016-01-01

    Fusobacterium nucleatum has been associated with both periodontal disease and inflammatory bowel disease. This Gram-negative bacterium possesses a high inflammatory potential that may contribute to the disease process. We hypothesized that green and black tea polyphenols attenuate the inflammatory response of monocytes/macrophages mediated by F. nucleatum. We first showed that the tea extracts, EGCG and theaflavins reduce the NF-κB activation induced by F. nucleatum in monocytes. Since NF-κB is a key regulator of genes coding for inflammatory mediators, we tested the effects of tea polyphenols on secretion of IL-1β, IL-6, TNF-α, and CXCL8 by macrophages. A pre-treatment of macrophages with the tea extracts, EGCG, or theaflavins prior to a stimulation with F. nucleatum significantly inhibited the secretion of all four cytokines and reduced the secretion of MMP-3 and MMP-9, two tissue destructive enzymes. TREM-1 expressed by macrophages is a cell-surface receptor involved in the propagation of the inflammatory response to bacterial challenges. Interestingly, tea polyphenols inhibited the secretion/shedding of soluble TREM-1 induced by a stimulation of macrophages with F. nucleatum. The anti-inflammatory properties of tea polyphenols identified in the present study suggested that they may be promising agents for the prevention and/or treatment of periodontal disease and inflammatory bowel disease. PMID:27694921

  18. Glycine tomentella Hayata inhibits IL-1β and IL-6 production, inhibits MMP-9 activity, and enhances RAW264.7 macrophage clearance of apoptotic cells

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    Sun Yu-Shu

    2010-11-01

    Full Text Available Abstract Background To assess the effects of Glycine tomentella Hayata (GTH, a traditional herbal medicine for treatment of rheumatic diseases on the expression of the proinflammatory cytokines and on the clearance of apoptotic cells by macrophages. Methods RAW264.7 cells were cultured with lipopolysaccharide (LPS in the presence or absence of ethanol extract of GTH. The expression of proinflammatory cytokines IL-1β, IL-6, and TNF-α, and inducible nitric oxide synthase (iNOS and transglutaminase 2 (TG2 were assayed by reverse transcriptase-polymerase chain reaction (RT-PCR and enzyme-linked immunosorbent assay (ELISA. Matrix metalloproteinase (MMP-2 and MMP-9 were assayed by gelatin zymography. For detecting uptake of apoptotic cells, RAW264.7 cells were cultured with carboxyfluorescein diacetate (CFDA-stained apoptotic cells and assayed by flow cytometry. Results The major components of GTH analyzed by high-performance liquid chromatography (HPLC chromatogram were daidzein (42.5%, epicatechin (28.8%, and naringin (9.4%. GTH treatment inhibited the expression of proinflammatory cytokines IL-1β, IL-6 and MMP-9 but did not affect the expression of TNF-α and iNOS. GTH significantly enhanced the expression of TG2 and the clearance of apoptotic cells by RAW264.7 macrophages. Conclusions GTH inhibits proinflammatory cytokine secretion and MMP-9 activity, enhances apoptotic cell uptake and up-regulates TG2 expression. Our data show that GTH might have beneficial effects on rheumatic diseases.

  19. Bone Marrow Mesenchymal Stem Cells Inhibit Lipopolysaccharide-Induced Inflammatory Reactions in Macrophages and Endothelial Cells

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    Dequan Li

    2016-01-01

    Full Text Available Background. Systemic inflammatory response syndrome (SIRS accompanied by trauma can lead to multiple organ dysfunction syndrome (MODS and even death. Early inhibition of the inflammation is necessary for damage control. Bone marrow mesenchymal stem cells (BMSCs, as a novel therapy modality, have been shown to reduce inflammatory responses in human and animal models. Methods. In this study, we used Western blot, quantitative PCR, and enzyme-linked immunosorbent assay (ELISA to assess the activity of BMSCs to suppress the inflammation induced by lipopolysaccharide (LPS in human umbilical cord endothelial cells (HUVECs and alveolar macrophages. Results. Our results demonstrated that LPS caused an inflammatory response in alveolar macrophages and HUVECs, increased permeability of HUVEC, upregulated expression of toll-like receptor (TLR 2, TLR4, phosphorylated p65, downregulated release of IL10, and promoted release of TNF-α in both cells. Coculture with BMSCs attenuated all of these activities induced by LPS in the two tested cell types. Conclusions. Together, our results demonstrate that BMSCs dosage dependently attenuates the inflammation damage of alveolar macrophages and HUVECs induced by LPS.

  20. Sites of inhibition of mitochondrial electron transport in macrophage-injured neoplastic cells.

    Science.gov (United States)

    Granger, D L; Lehninger, A L

    1982-11-01

    Previous work has shown that injury of neoplastic cells by cytotoxic macrophages (CM) in cell culture is accompanied by inhibition of mitochondrial respiration. We have investigated the nature of this inhibition by studying mitochondrial respiration in CM-injured leukemia L1210 cells permeabilized with digitonin. CM-induced injury affects the mitochondrial respiratory chain proper. Complex I (NADH-coenzyme Q reductase) and complex II (succinate-coenzyme Q reductase) are markedly inhibited. In addition a minor inhibition of cytochrome oxidase was found. Electron transport from alpha-glycerophosphate through the respiratory chain to oxygen is unaffected and permeabilized CM-injured L1210 cells oxidizing this substrate exhibit acceptor control. However, glycerophosphate shuttle activity was found not to occur within CM-injured or uninjured L1210 cells in culture hence, alpha-glycerophosphate is apparently unavailable for mitochondrial oxidation in the intact cell. It is concluded that the failure of respiration of intact neoplastic cells injured by CM is caused by the nearly complete inhibition of complexes I and II of the mitochondrial electron transport chain. The time courses of CM-induced electron transport inhibition and arrest of L1210 cell division are examined and the possible relationship between these phenomena is discussed.

  1. Inhibition of SIK2 and SIK3 during differentiation enhances the anti-inflammatory phenotype of macrophages

    Science.gov (United States)

    Darling, Nicola J.; Toth, Rachel; Arthur, J. Simon C.

    2017-01-01

    The salt-inducible kinases (SIKs) control a novel molecular switch regulating macrophage polarization. Pharmacological inhibition of the SIKs induces a macrophage phenotype characterized by the secretion of high levels of anti-inflammatory cytokines, including interleukin (IL)-10, and the secretion of very low levels of pro-inflammatory cytokines, such as tumour necrosis factor α. The SIKs, therefore, represent attractive new drug targets for the treatment of macrophage-driven diseases, but which of the three isoforms, SIK1, SIK2 or SIK3, would be appropriate to target remains unknown. To address this question, we developed knock-in (KI) mice for SIK1, SIK2 and SIK3, in which we introduced a mutation that renders the enzymes catalytically inactive. Characterization of primary macrophages from the single and double KI mice established that all three SIK isoforms, and in particular SIK2 and SIK3, contribute to macrophage polarization. Moreover, we discovered that inhibition of SIK2 and SIK3 during macrophage differentiation greatly enhanced the production of IL-10 compared with their inhibition in mature macrophages. Interestingly, macrophages differentiated in the presence of SIK inhibitors, MRT199665 and HG-9-91-01, still produced very large amounts of IL-10, but very low levels of pro-inflammatory cytokines, even after the SIKs had been reactivated by removal of the drugs. Our data highlight an integral role for SIK2 and SIK3 in innate immunity by preventing the differentiation of macrophages into a potent and stable anti-inflammatory phenotype. PMID:27920213

  2. Apolipoprotein E inhibits toll-like receptor (TLR)-3- and TLR-4-mediated macrophage activation through distinct mechanisms.

    Science.gov (United States)

    Zhu, Yanjuan; Kodvawala, Ahmer; Hui, David Y

    2010-04-28

    Previous studies have shown that apoE (apolipoprotein E) expression in macrophages suppresses inflammatory responses; however, whether endogenously synthesized apoE acts intracellularly or after its secretion in suppressing macrophage inflammation remains unclear. The present study used the murine monocyte macrophage cell line RAW 264.7 to examine the influence of exogenous apoE on macrophage inflammatory responses induced by TLR (Toll-like receptor)-4 and TLR-3 agonists LPS (lipopolysaccharide) and poly(I-C) respectively. Results showed that exogenously added apoE suppressed the LPS and poly(I-C) induction of IL (interleukin)-6, IL-1beta and TNF-alpha (tumour necrosis factor-alpha) secretion by RAW 264.7 cells. The mechanism was related to apoE suppression of TLR-agonist-induced phosphorylation of JNK (c-Jun N-terminal kinase) and c-Jun. A peptide containing the tandem repeat sequence of the receptor-binding domain of apoE, apoE-(141-155)2, was similarly effective in inhibiting LPS- and poly(I-C)-induced macrophage inflammatory responses. Reductive methylation of lysine residues in apoE, which abolished its receptor-binding capability without affecting its ability to interact with HSPGs (heparin sulfate proteoglycans), inhibited the ability of apoE to suppress macrophage responses to LPS, but had no effect on apoE suppression of poly(I-C)-induced macrophage activation. The ability of apoE to suppress poly(I-C)-induced pro-inflammatory cytokine production was abolished by heparinase treatment of RAW 264.7 cells to remove cell-surface HSPGs. Taken together, these results indicate that exogenous apoE inhibits macrophage inflammatory responses to TLR-4 and TLR-3 agonists through distinct mechanisms related to receptor and HSPG binding respectively, and that these inhibitory effects converged on suppression of JNK and c-Jun activation which are necessary for macrophage activation.

  3. Clinical significance of tumor-associated macrophage infiltration in supraglottic laryngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    Jia-Ying Lin; Xiao-Yan Li; Nakashima Tadashi; Ping Dong

    2011-01-01

    Tumor-associated macrophages (TAMs) can elicit contrasting effects on tumor progression, depending on different tumor microenvironment. This study aimed to explore the correlation between TAM infiltration and clinicopathologic characteristics, metastasis, and prognosis of supraglottic laryngeal carcinoma. TAMs in intratumoral and peritumoral regions of 84 specimens of supraglottic laryngeal carcinoma tissues were detected by immunohistochemical staining with monoclonal CD68 antibody. The density of peritumoral CD68+ TAMs in recurrence cases (9/11) and in dead cases (17/23) were significantly higher than those in non-recurrence cases (33/73) and in survival cases (25/61), with significant differences (P = 0.024 and 0.007, respectively). The Kaplan-Meier survival analysis showed a significant relationship between the infiltration of both intratumoral and peritumoral CD68+ TAMs and the overall survival of patients. The 5year survival rate was significantly lower in the group with a high density of intratumoral CD68+ TAMs than in the group with a low density (39.6% vs. 82.5%, P < 0.05). Similarly, the 5-year survival rate was significantly lower in the group with a high density of peritumoral CD68+ TAMs than in the group with a low density (50.6% vs. 73.1%, P < 0.05). Cox regression analysis revealed that T classification, distant metastasis, and intratumoral or peritumoral CD68+ TAMs were independent factors for disease-free survival, whereas T classification and intratumoral CD68+ TAMs were independent factors for overall survival. The results indicate that TAM infiltration in supraglottic laryngeal caminoma can be used to predict metastasis and prognosis and is an independent factor for prognosis.

  4. Activated niacin receptor HCA2 inhibits chemoattractant-mediated macrophage migration via Gβγ/PKC/ERK1/2 pathway and heterologous receptor desensitization

    Science.gov (United States)

    Shi, Ying; Lai, Xiangru; Ye, Lingyan; Chen, Keqiang; Cao, Zheng; Gong, Wanghua; Jin, Lili; Wang, Chunyan; Liu, Mingyong; Liao, Yuan; Wang, Ji Ming; Zhou, Naiming

    2017-01-01

    The niacin receptor HCA2 is implicated in controlling inflammatory host responses with yet poorly understood mechanistic basis. We previously reported that HCA2 in A431 epithelial cells transduced Gβγ-protein kinase C- and Gβγ-metalloproteinase/EGFR-dependent MAPK/ERK signaling cascades. Here, we investigated the role of HCA2 in macrophage-mediated inflammation and the underlying mechanisms. We found that proinflammatory stimulants LPS, IL-6 and IL-1β up-regulated the expression of HCA2 on macrophages. Niacin significantly inhibited macrophage chemotaxis in response to chemoattractants fMLF and CCL2 by disrupting polarized distribution of F-actin and Gβ protein. Niacin showed a selected additive effect on chemoattractant-induced activation of ERK1/2, JNK and PI3K pathways, but only the MEK inhibitor UO126 reduced niacin-mediated inhibition of macrophage chemotaxis, while activation of ERK1/2 by EGF alone did not inhibit fMLF-mediated migration of HEK293T cells co-expressing HCA2 and fMLF receptor FPR1. In addition, niacin induced heterologous desensitization and internalization of FPR1. Furthermore, niacin rescued mice from septic shock by diminishing inflammatory symptoms and the effect was abrogated in HCA2−/− mice. These results suggest that Gβγ/PKC-dependent ERK1/2 activation and heterologous desensitization of chemoattractant receptors are involved in the inhibition of chemoattractant-induced migration of macrophages by niacin. Thus, HCA2 plays a critical role in host protection against pro-inflammatory insults. PMID:28186140

  5. RGS4 inhibits angiotensin II signaling and macrophage localization during renal reperfusion injury independent of vasospasm.

    Science.gov (United States)

    Pang, Paul; Jin, Xiaohua; Proctor, Brandon M; Farley, Michelle; Roy, Nilay; Chin, Matthew S; von Andrian, Ulrich H; Vollmann, Elisabeth; Perro, Mario; Hoffman, Ryan J; Chung, Joseph; Chauhan, Nikita; Mistri, Murti; Muslin, Anthony J; Bonventre, Joseph V; Siedlecki, Andrew M

    2015-04-01

    Vascular inflammation is a major contributor to the severity of acute kidney injury. In the context of vasospasm-independent reperfusion injury we studied the potential anti-inflammatory role of the Gα-related RGS protein, RGS4. Transgenic RGS4 mice were resistant to 25 min injury, although post-ischemic renal arteriolar diameter was equal to the wild type early after injury. A 10 min unilateral injury was performed to study reperfusion without vasospasm. Eighteen hours after injury, blood flow was decreased in the inner cortex of wild-type mice with preservation of tubular architecture. Angiotensin II levels in the kidneys of wild-type and transgenic mice were elevated in a sub-vasoconstrictive range 12 and 18 h after injury. Angiotensin II stimulated pre-glomerular vascular smooth muscle cells (VSMCs) to secrete the macrophage chemoattractant RANTES, a process decreased by angiotensin II R2 (AT2) inhibition. However, RANTES increased when RGS4 expression was suppressed implicating Gα protein activation in an AT2-RGS4-dependent pathway. RGS4 function, specific to VSMC, was tested in a conditional VSMC-specific RGS4 knockout showing high macrophage density by T2 MRI compared with transgenic and non-transgenic mice after the 10 min injury. Arteriolar diameter of this knockout was unchanged at successive time points after injury. Thus, RGS4 expression, specific to renal VSMC, inhibits angiotensin II-mediated cytokine signaling and macrophage recruitment during reperfusion, distinct from vasomotor regulation.

  6. Glycyrrhiza glabra L. Extract Inhibits LPS-Induced Inflammation in RAW Macrophages.

    Science.gov (United States)

    Li, Chunmei; Eom, Taekil; Jeong, Yoonhwa

    2015-01-01

    Glycyrrhiza glabra has been used in medicine for thousands of years. Our previous study revealed that the methanolic extract of Glycyrrhiza glabra L. (EGGR) exhibits significant nitric oxide (NO) inhibitory effect on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages among 100 other extracts. Accordingly, the aim of the present study was to investigate the potential anti-inflammatory effect of EGGR. The anti-inflammatory effect of EGGR on LPS-stimulated RAW 264.7 macrophages was measured by MTT assay, NO content analysis, reactive oxygen species (ROS) level analysis, RT-PCR, Western blot analysis, and ELISA assay. Low doses of EGGR were non-toxic to macrophages and imparted protective effect against LPS induced cell death. Incubation of LPS-treated macrophages with 100 μg/mL EGGR led to an increase in cell viability from 66.6 to 99%. Moreover, EGGR led to down regulation of NO (NO2+NO3) and ROS productions in a dose-dependent manner. In particular, 100 μg/mL EGGR led to a reduction in NO2+NO3 level from 336.2 to 24.1 pM/mL, and ROS level from 483.5 to 128.4%. Consistent with the result related to NO production, EGGR suppressed the ability of LPS to induce mRNA and protein expressions of nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) cytokines, tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), and IL-6 productions which were analyzed by an ELISA assay. These results provide a comprehensive approach into the anti-inflammatory effect of EGGR on LPS-stimulated macrophages; however, efforts are underway on gaining detailed insight into anti-inflammatory signaling pathways.

  7. Herp depletion inhibits zearalenone-induced cell death in RAW 264.7 macrophages.

    Science.gov (United States)

    Chen, Fenglei; Lin, Pengfei; Wang, Nan; Yang, Diqi; Wen, Xin; Zhou, Dong; Wang, Aihua; Jin, Yaping

    2016-04-01

    Herp is an endoplasmic reticulum (ER) membrane protein and strongly induced by the ER stress that not only participates in the unfolded protein response (UPR) under the ER stress, but also in cell autophagy under glucose starvation (GS). However, we do not know whether Herp plays any roles in other responses, such as zearalenone (ZEA). In this study, we constructed recombinant lentiviral vectors for Herp shRNA expression and generated stable Herp knockdown RAW 264.7 macrophages. Flow cytometry analysis showed Herp depletion could inhibit cell death induced by ZEA. Western blot analysis revealed that Herp depletion could up-regulate autophagy-related protein LC3-I conversion into LC3-II and the expression of ER stress-related protein CHOP. These results suggest that Herp depletion inhibits cell death by up-regulating autophagy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Sirtuin inhibition attenuates the production of inflammatory cytokines in lipopolysaccharide-stimulated macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Fernandes, Claudia A. [Universite catholique de Louvain, Louvain Drug Research Institute (LDRI), Pharmaceutics and Drug Delivery Research Group, Brussels B-1200 (Belgium); Fievez, Laurence [University of Liege, GIGA-Research, Laboratory of Cellular and Molecular Immunology, Liege B-4000 (Belgium); Neyrinck, Audrey M.; Delzenne, Nathalie M. [Universite catholique de Louvain, LDRI, Metabolism and Nutrition Research Group, Brussels B-1200 (Belgium); Bureau, Fabrice [University of Liege, GIGA-Research, Laboratory of Cellular and Molecular Immunology, Liege B-4000 (Belgium); Vanbever, Rita, E-mail: rita.vanbever@uclouvain.be [Universite catholique de Louvain, Louvain Drug Research Institute (LDRI), Pharmaceutics and Drug Delivery Research Group, Brussels B-1200 (Belgium)

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer Lipopolysaccharide-stimulated macrophages were treated with cambinol and sirtinol. Black-Right-Pointing-Pointer Cambinol and sirtinol decreased lipopolysaccharide-induced cytokines. Black-Right-Pointing-Pointer Cambinol decreased NF-{kappa}B activity but had no impact on p38 MAPK activation. Black-Right-Pointing-Pointer Sirtuins are an interesting target for the treatment of inflammatory diseases. -- Abstract: In several inflammatory conditions such as rheumatoid arthritis or sepsis, the regulatory mechanisms of inflammation are inefficient and the excessive inflammatory response leads to damage to the host. Sirtuins are class III histone deacetylases that modulate the activity of several transcription factors that are implicated in immune responses. In this study, we evaluated the impact of sirtuin inhibition on the activation of lipopolysaccharide (LPS)-stimulated J774 macrophages by assessing the production of inflammatory cytokines. The pharmacologic inhibition of sirtuins decreased the production of tumour necrosis factor-alpha (TNF-{alpha}) interleukin 6 (IL-6) and Rantes. The reduction of cytokine production was associated with decreased nuclear factor kappa B (NF-{kappa}B) activity and inhibitor kappa B alpha (I{kappa}B{alpha}) phosphorylation while no impact was observed on the phosphorylation status of p38 mitogen-activated kinase (p38 MAPK). This work shows that sirtuin pharmacologic inhibitors are a promising tool for the treatment of inflammatory conditions.

  9. Inhibition of nitric oxide and inflammatory cytokines in LPS-stimulated murine macrophages by resveratrol, a potent proteasome inhibitor

    Directory of Open Access Journals (Sweden)

    Qureshi Asaf A

    2012-07-01

    Full Text Available Abstract Background Altered immune function during ageing results in increased production of nitric oxide (NO and other inflammatory mediators. Recently, we have reported that NO production was inhibited by naturally-occurring proteasome inhibitors (quercetin, δ-tocotrienol, and riboflavin in lipopolysaccharide (LPS-stimulated RAW264.7 cells, and thioglycolate-elicited peritoneal macrophages from C57BL/6 mice. In a continuous effort to find more potent, non-toxic, commercially available, naturally-occurring proteasome inhibitors that suppress inflammation, the present study was carried out to describe the inhibition of NF-κB activation and NO, TNF-α, IL-6, IL-1β, and iNOS expression by trans-resveratrol, trans-pterostilbene, morin hydrate, and nicotinic acid in LPS-induced RAW 264.7 cells and thioglycolate-elicited peritoneal macrophages from C57BL/6 and BALB/c mice. Results The present results indicate that resveratrol, pterostilbene, and morin hydrate caused significant inhibition (>70% to 90%; P 40%; P 60%; P 40%; P P  Conclusions The present results clearly demonstrate that resveratrol and pterostilbene are particularly potent proteasome inhibitors that suppress expression of genes, and production of inflammatory products in LPS-stimulated RAW 264.7 cells, and macrophages from C57BL/6 and BALB/c mice. Resveratrol and pterostilbene which are present in grapes, blueberries, and red wine, have been implicated as contributing factors to the lower incidence of cardiovascular disease in the French population, despite their relatively high dietary fat intake. Consequently, it appears likely that the beneficial nutritional effects of resveratrol and pterostilbene are due at least in part, to their ability to inhibit NF-κB activation by the proteasome, thereby suppressing activation of pro-inflammatory cytokines and iNOS genes, resulting in decreased secretion of TNF-α, IL-1β, IL-6, and NO levels, in response to inflammatory stimuli

  10. Marrubium vulgare extract inhibits human-LDL oxidation and enhances HDL-mediated cholesterol efflux in THP-1 macrophage.

    Science.gov (United States)

    Berrougui, Hicham; Isabelle, Maxim; Cherki, Mounia; Khalil, Abdelouahed

    2006-12-14

    The objective of the present study was to elucidate the beneficial properties of aqueous extracts of Marrubium vulgare (AEM) towards cardiovascular disease by protecting human-LDL against lipid peroxidation and promoting HDL-mediated cholesterol efflux. Human-LDL were oxidised by incubation with CuSO(4) in the presence of increased concentrations of AEM (0-100 microg/ml). LDL lipid peroxidation was evaluated by conjugated diene formation, vitamin E disappearance as well as LDL-electrophoretic mobility. HDL-mediated cholesterol efflux assay was carried out in human THP-1 macrophages. Incubation of LDL with AEM significantly prolonged the lag phase (P=0.014), lowered the progression rate of lipid peroxidation (P=0.004), reduced the disappearance of vitamin E and the electrophoretic mobility in a dose-dependent manner. Also, incubation of HDL with AEM significantly increased HDL-mediated cholesterol efflux from THP-1 macrophages implicating an independent ATP binding cassette A1 (ABCA1) pathways. Our findings suggest that M. vulgare provides a source of natural antioxidants, which inhibit LDL oxidation and enhance reverse cholesterol transport and thus can prevent cardiovascular diseases development. These antioxidant properties increase the anti-atherogenic potential of HDL.

  11. Inhibition of nitric oxide enhances ovine lentivirus replication in monocyte-derived macrophages.

    Science.gov (United States)

    Keane, Kevin A; Mason, Gary L; DeMartini, James C

    2002-12-01

    Ovine lentivirus (OvLV) also known as maedi-visna virus, infects and replicates primarily in macrophages. This investigation examined the role of nitric oxide in the replication of OvLV in cultured macrophages. Peripheral blood mononuclear cells were collected from OvLV-free sheep and cultured in Teflon coated flasks at a high concentration of lamb serum. The cells were subsequently infected with OvLV strain 85/34. OvLV replication was assessed under different experimental treatments by comparison of reverse transcriptase (RT) activity in culture supernatant. Cultures that were treated with exogenous nitric oxide via S-nitroso-acetylpenicillamine did not have altered levels of RT activity compared to cultures treated with the inactive control compound, acetylpenicillamine. However, blockage of nitric oxide production by treatment with aminoguanidine, a competitive inhibitor of inducible nitric oxide synthase (iNOS), led to a significant rise in RT activity. This rise in RT activity was partially reversed in aminoguanidine treated cultures by L-arginine, the normal substrate for iNOS. Finally, the number of viral antigen producing cells was also quantified after aminoguanidine treatment and found to be significantly higher than untreated cultures. Collectively, these results indicate that nitric oxide is a negative regulator of OvLV replication in macrophages.

  12. The effects of a cyclooxygenase-2 (COX-2 expression and inhibition on human uveal melanoma cell proliferation and macrophage nitric oxide production

    Directory of Open Access Journals (Sweden)

    Marshall Jean-Claude

    2007-01-01

    Full Text Available Abstract Background Cyclooxygenase-2 (COX-2 expression has previously been identified in uveal melanoma although the biological role of COX-2 in this intraocular malignancy has not been elucidated. This study aimed to investigate the effect of a COX-2 inhibitor on the proliferation rate of human uveal melanoma cells, as well as its effect on the cytotoxic response of macrophages. Methods Human uveal melanoma cell lines were transfected to constitutively express COX-2 and the proliferative rate of these cells using two different methods, with and without the addition of Amfenac, was measured. Nitric oxide production by macrophages was measured after exposure to melanoma-conditioned medium from both groups of cells as well as with and without Amfenac, the active metabolite of Nepafenac. Results Cells transfected to express COX-2 had a higher proliferation rate than those that did not. The addition of Amfenac significantly decreased the proliferation rate of all cell lines. Nitric oxide production by macrophages was inhibited by the addition of melanoma conditioned medium, the addition of Amfenac partially overcame this inhibition. Conclusion Amfenac affected both COX-2 transfected and non-transfected uveal melanoma cells in terms of their proliferation rates as well as their suppressive effects on macrophage cytotoxic activity.

  13. Semecarpus anacardium L, nuts inhibit lipopolysaccharide induced NO production in rat macrophages along with its hypolipidemic property.

    Science.gov (United States)

    Tripathi, Y B; Pandey, R S

    2004-04-01

    Traditionally S. anacardium is used for rejuvenation, rheumatoid arthritis, fever and neurological disorders. In the present study it was observed that a fraction of S. anacacrdium at dose of 1 mg/100 g body wt, significantly reduced serum cholesterol from 378.87 mg/dl in the rats fed with atherogenic diet (AD) to 197.99 mg/dl (45-52%) in the rats fed with AD diet and increased serum HDL-cholesterol (33-37%). The same fraction also inhibited LPS induced NO production in the culture activated rat peritoneal macrophages in the dose dependent manner with IC50 value at 50 ng/ml of the culture medium. The drug in the above doses was completely safe and non-toxic, (no change in the enzymes), to liver and kidney functions.

  14. HIV-1 inhibits phagocytosis and inflammatory cytokine responses of human monocyte-derived macrophages to P. falciparum infected erythrocytes.

    Directory of Open Access Journals (Sweden)

    Louise E Ludlow

    Full Text Available HIV-1 infection increases the risk and severity of malaria by poorly defined mechanisms. We investigated the effect of HIV-1(Ba-L infection of monocyte-derived macrophages (MDM on phagocytosis of opsonised P. falciparum infected erythrocytes (IE and subsequent proinflammatory cytokine secretion. Compared to mock-infected MDM, HIV-1 infection significantly inhibited phagocytosis of IE (median (IQR (10 (0-28 versus (34 (27-108; IE internalised/100 MDM; p = 0.001 and decreased secretion of IL-6 (1,116 (352-3,387 versus 1,552 (889-6,331; pg/mL; p = 0.0078 and IL-1β (16 (7-21 versus 33 (27-65; pg/mL; p = 0.0078. Thus inadequate phagocytosis and cytokine production may contribute to impaired control of malaria in HIV-1 infected individuals.

  15. Targeting tumor-associated macrophages and inhibition of MCP-1 reduce angiogenesis and tumor growth in a human melanoma xenograft.

    Science.gov (United States)

    Gazzaniga, Silvina; Bravo, Alicia I; Guglielmotti, Angelo; van Rooijen, Nico; Maschi, Fabricio; Vecchi, Annunciata; Mantovani, Alberto; Mordoh, José; Wainstok, Rosa

    2007-08-01

    Chemokines such as monocyte chemoattractant protein (MCP)-1 are key agonists that attract macrophages to tumors. In melanoma, it has been previously shown that variable levels of MCP-1/CCL2 appear to correlate with infiltrating macrophages and tumor fate, with low to intermediate levels of the chemokine contributing to melanoma development. To work under such conditions, a poorly tumorigenic human melanoma cell line was transfected with an expression vector encoding MCP-1. We found that M2 macrophages are associated to MCP-1+ tumors, triggering a profuse vascular network. To target the protumoral macrophages recruitment and reverting tumor growth promotion, clodronate-laden liposomes (Clod-Lip) or bindarit were administered to melanoma-bearing mice. Macrophage depletion after Clod-Lip treatment induced development of smaller tumors than in untreated mice. Immunohistochemical analysis with an anti-CD31 antibody revealed scarce vascular structures mainly characterized by narrow vascular lights. Pharmacological inhibition of MCP-1 with bindarit also reduced tumor growth and macrophage recruitment, rendering necrotic tumor masses. We suggest that bindarit or Clod-Lip abrogates protumoral-associated macrophages in human melanoma xenografts and could be considered as complementary approaches to antiangiogenic therapy.

  16. The significance of T cells, B cells, antibodies and macrophages against encephalomyocarditis (EMC)-D virus-induced diabetes in mice.

    Science.gov (United States)

    Kounoue, Etsushi; Izumi, Ken-ichi; Ogawa, Shuichiro; Kondo, Shiori; Katsuta, Hitoshi; Akashi, Tomoyuki; Niho, Yoshiyuki; Harada, Mine; Tamiya, Sadafumi; Kurisaki, Hironori; Nagafuchi, Seiho

    2008-01-01

    In order to clarify the significance of protective mechanisms against encephalomyocarditis (EMC) virus-induced diabetes in mice, we studied the relative importance of T cells, B cells, antibodies and macrophages in the prevention of virus-induced diabetes. Neither T cell-deficient athymic nude mice nor B cell-deficient microMT/microMT mice showed an enhanced clinical course of EMC-D virus-induced diabetes, indicating that neither T cells nor B cells played a major role in the protection against EMC-D-virus-induced diabetes. Transfer of a large amount of antiserum to EMC-D-virus-infected mice protected the development of diabetes only when transferred within 36 h of infection, the timing of which was earlier than that for the production of natural neutralizing antibodied. Since pretreatment of mice with the macrophage-activating immunopotentiator Corynebacterium parvum (CP) completely prevented the development of diabetes, we studied the clinical outcome of EMC-D-virus-infected mice pretreated with CP. Mice treated with CP showed reduced proliferation of EMC-D virus in the affected organs, including the pancreas, while the levels of development of neutralizing antibody and serum interferon were not enhanced compared with the controls. Finally, we studied the macrophages derived from mice pretreated with CP and found that they inhibited the growth of EMC-D virus in vitro more than those derived from non-treated and thioglycolate-treated mice. Taken together, it can be suggested that neither T cells nor B cells, which have to do with adaptive immunity, play a significant role in the pathogenesis of EMC-D-virus-induced diabetes, while innate immunity, which is dependent on activated macrophages, contributes to in vivo resistance against EMC-D-virus-induced diabetes.

  17. Pharmacological inhibition of the chemokine CXCL16 diminishes liver macrophage infiltration and steatohepatitis in chronic hepatic injury.

    Directory of Open Access Journals (Sweden)

    Alexander Wehr

    Full Text Available Non-alcoholic fatty liver disease (NAFLD is a major cause of morbidity and mortality in developed countries, resulting in steatohepatitis (NASH, fibrosis and eventually cirrhosis. Modulating inflammatory mediators such as chemokines may represent a novel therapeutic strategy for NAFLD. We recently demonstrated that the chemokine receptor CXCR6 promotes hepatic NKT cell accumulation, thereby controlling inflammation in experimental NAFLD. In this study, we first investigated human biopsies (n = 20, confirming that accumulation of inflammatory cells such as macrophages is a hallmark of progressive NAFLD. Moreover, CXCR6 gene expression correlated with the inflammatory activity (ALT levels in human NAFLD. We then tested the hypothesis that pharmacological inhibition of CXCL16 might hold therapeutic potential in NAFLD, using mouse models of acute carbon tetrachloride (CCl4- and chronic methionine-choline-deficient (MCD diet-induced hepatic injury. Neutralizing CXCL16 by i.p. injection of anti-CXCL16 antibody inhibited the early intrahepatic NKT cell accumulation upon acute toxic injury in vivo. Weekly therapeutic anti-CXCL16 administrations during the last 3 weeks of 6 weeks MCD diet significantly decreased the infiltration of inflammatory macrophages into the liver and intrahepatic levels of inflammatory cytokines like TNF or MCP-1. Importantly, anti-CXCL16 treatment significantly reduced fatty liver degeneration upon MCD diet, as assessed by hepatic triglyceride levels, histological steatosis scoring and quantification of lipid droplets. Moreover, injured hepatocytes up-regulated CXCL16 expression, indicating that scavenging functions of CXCL16 might be additionally involved in the pathogenesis of NAFLD. Targeting CXCL16 might therefore represent a promising novel therapeutic approach for liver inflammation and steatohepatitis.

  18. Pirfenidone ameliorates murine chronic GVHD through inhibition of macrophage infiltration and TGF-β production.

    Science.gov (United States)

    Du, Jing; Paz, Katelyn; Flynn, Ryan; Vulic, Ante; Robinson, Tara M; Lineburg, Katie E; Alexander, Kylie A; Meng, Jingjing; Roy, Sabita; Panoskaltsis-Mortari, Angela; Loschi, Michael; Hill, Geoffrey R; Serody, Jonathan S; Maillard, Ivan; Miklos, David; Koreth, John; Cutler, Corey S; Antin, Joseph H; Ritz, Jerome; MacDonald, Kelli P; Schacker, Timothy W; Luznik, Leo; Blazar, Bruce R

    2017-03-02

    Allogeneic hematopoietic stem cell transplantation is hampered by chronic graft-versus-host disease (cGVHD) resulting in multi-organ fibrosis and diminished function. Fibrosis in lung and skin leads to progressive bronchiolitis obliterans (BO) and scleroderma, respectively, for which new treatments are needed. We evaluated pirfenidone, a FDA approved drug for idiopathic pulmonary fibrosis, for its therapeutic effect in cGVHD mouse models with distinct pathophysiology. In a full MHC-mismatched, multi-organ system model with BO, donor T cell responses that support pathogenic antibody production are required for cGVHD development. Pirfenidone treatment beginning one month post-transplant restored pulmonary function and reversed lung fibrosis, which was associated with reduced macrophage infiltration and TGF-β production. Pirfenidone dampened splenic germinal center B cell and T follicular helper cell frequencies that collaborate to produce antibody. In both a minor histocompatibility antigen-mismatched as well as a MHC-haploidentical model of sclerodermatous cGVHD, pirfenidone significantly reduced macrophages in the skin, although clinical improvement of scleroderma was only seen in one model. In vitro chemotaxis assays demonstrated that pirfenidone impaired macrophage migration to MCP-1 as well as IL-17A, that has been linked to cGVHD generation. Taken together, our data suggest that pirfenidone is a potential therapeutic agent to ameliorate fibrosis in cGVHD.

  19. Pharmacologic or Genetic Targeting of Glutamine Synthetase Skews Macrophages toward an M1-like Phenotype and Inhibits Tumor Metastasis

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    Erika M. Palmieri

    2017-08-01

    Full Text Available Glutamine-synthetase (GS, the glutamine-synthesizing enzyme from glutamate, controls important events, including the release of inflammatory mediators, mammalian target of rapamycin (mTOR activation, and autophagy. However, its role in macrophages remains elusive. We report that pharmacologic inhibition of GS skews M2-polarized macrophages toward the M1-like phenotype, characterized by reduced intracellular glutamine and increased succinate with enhanced glucose flux through glycolysis, which could be partly related to HIF1α activation. As a result of these metabolic changes and HIF1α accumulation, GS-inhibited macrophages display an increased capacity to induce T cell recruitment, reduced T cell suppressive potential, and an impaired ability to foster endothelial cell branching or cancer cell motility. Genetic deletion of macrophagic GS in tumor-bearing mice promotes tumor vessel pruning, vascular normalization, accumulation of cytotoxic T cells, and metastasis inhibition. These data identify GS activity as mediator of the proangiogenic, immunosuppressive, and pro-metastatic function of M2-like macrophages and highlight the possibility of targeting this enzyme in the treatment of cancer metastasis.

  20. Inhibition of macrophage activation by the myxoma virus M141 protein (vCD200).

    Science.gov (United States)

    Zhang, Leiliang; Stanford, Marianne; Liu, Jia; Barrett, Catherine; Jiang, Lei; Barclay, A Neil; McFadden, Grant

    2009-09-01

    The M141 protein of myxoma virus (MYXV) is a viral CD200 homolog (also called vOX-2) that inhibits macrophage activation in infected rabbits. Here, we show that murine myeloid RAW 264.7 cells became activated when infected with MYXV in which the M141 gene was deleted (vMyx-M141KO) but not with the parental wild-type MYXV. Moreover, transcript and protein levels of tumor necrosis factor and granulocyte colony-stimulating factor were rapidly upregulated in an NF-kappaB-dependent fashion in the RAW 264.7 cells infected with vMyx-M141KO. M141 protein is present in the virion and counteracts this NF-kappaB activation pathway upon infection with the wild-type MYXV. Our data suggest that upregulation of these classic macrophage-related proinflammatory cytokine markers following infection of myeloid cells with the M141-knockout MYXV is mediated via the rapid activation of the cellular NF-kappaB pathway.

  1. A novel hybrid aspirin-NO-releasing compound inhibits TNFalpha release from LPS-activated human monocytes and macrophages

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    Fox Sarah

    2008-07-01

    Full Text Available Abstract Background The cytoprotective nature of nitric oxide (NO led to development of NO-aspirins in the hope of overcoming the gastric side-effects of aspirin. However, the NO moiety gives these hybrids potential for actions further to their aspirin-mediated anti-platelet and anti-inflammatory effects. Having previously shown that novel NO-aspirin hybrids containing a furoxan NO-releasing group have potent anti-platelet effects, here we investigate their anti-inflammatory properties. Here we examine their effects upon TNFα release from lipopolysaccharide (LPS-stimulated human monocytes and monocyte-derived macrophages and investigate a potential mechanism of action through effects on LPS-stimulated nuclear factor-kappa B (NF-κB activation. Methods Peripheral venous blood was drawn from the antecubital fossa of human volunteers. Mononuclear cells were isolated and cultured. The resultant differentiated macrophages were treated with pharmacologically relevant concentrations of either a furoxan-aspirin (B8, B7; 10 μM, their respective furazan NO-free counterparts (B16, B15; 10 μM, aspirin (10 μM, existing nitroaspirin (NCX4016; 10 μM, an NO donor (DEA/NO; 10 μM or dexamethasone (1 μM, in the presence and absence of LPS (10 ng/ml; 4 h. Parallel experiments were conducted on undifferentiated fresh monocytes. Supernatants were assessed by specific ELISA for TNFα release and by lactate dehydrogenase (LDH assay for cell necrosis. To assess NF-κB activation, the effects of the compounds on the loss of cytoplasmic inhibitor of NF-κB, IκBα (assessed by western blotting and nuclear localisation (assessed by immunofluorescence of the p65 subunit of NF-κB were determined. Results B8 significantly reduced TNFα release from LPS-treated macrophages to 36 ± 10% of the LPS control. B8 and B16 significantly inhibited monocyte TNFα release to 28 ± 5, and 49 ± 9% of control, respectively. The B8 effect was equivalent in magnitude to that of

  2. Selenium nanoparticles incorporated into titania nanotubes inhibit bacterial growth and macrophage proliferation.

    Science.gov (United States)

    Liu, Wenwen; Golshan, Negar H; Deng, Xuliang; Hickey, Daniel J; Zeimer, Katherine; Li, Hongyi; Webster, Thomas J

    2016-08-25

    Since implants often fail due to infection and uncontrolled inflammatory responses, we designed an in vitro study to investigate the antibacterial and anti-inflammatory properties of titanium dioxide nanotubes (TNTs) incorporated with selenium nanoparticles (SeNPs). Selenium incorporation was achieved by the reaction of sodium selenite (Na2SeO3) with glutathione (GSH) under a vacuum in the presence of TNTs. Two types of bacteria and macrophages were cultured on the samples to determine their respective antibacterial and anti-inflammatory properties. The results showed that the TNT samples incorporating SeNPs (TNT-Se) inhibited the growth of Escherichia coli and Staphylococcus aureus compared to unmodified TNTs, albeit the SeNP concentration still needs to be optimized for maximal effect. At their maximum effect, the TNT-Se samples reduced the density of E. coli by 94.6% and of S. aureus by 89.6% compared to titanium controls. To investigate the underlying mechanism of this effect, the expression of six E. coli genes were tracked using qRT-PCR. Results indicated that SeNPs weakened E. coli membranes (ompA and ompF were down-regulated), decreased the function of adhesion-mediating proteins (csgA and csgG were progressively down-regulated with increasing SeNP content), and induced the production of damaging reactive oxygen species (ahpF was up-regulated). Moreover, TNT-Se samples inhibited the proliferation of macrophages, indicating that they can be used to control the inflammatory response and even prevent chronic inflammation, a condition that often leads to implant failure. In conclusion, we demonstrated that SeNP-TNTs display antibacterial and anti-inflammatory properties that are promising for improving the performance of titanium-based implants for numerous orthopedic and dental applications.

  3. The inhibition of macrophage foam cell formation by 9-cis β-carotene is driven by BCMO1 activity.

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    Noa Zolberg Relevy

    Full Text Available Atherosclerosis is a major cause of morbidity and mortality in developed societies, and begins when activated endothelial cells recruit monocytes and T-cells from the bloodstream into the arterial wall. Macrophages that accumulate cholesterol and other fatty materials are transformed into foam cells. Several epidemiological studies have demonstrated that a diet rich in carotenoids is associated with a reduced risk of heart disease; while previous work in our laboratory has shown that the 9-cis β-carotene rich alga Dunaliella inhibits atherogenesis in mice. The effect of 9-cis β-carotene on macrophage foam cell formation has not yet been investigated. In the present work, we sought to study whether the 9-cis β-carotene isomer, isolated from the alga Dunaliella, can inhibit macrophage foam cell formation upon its conversion to retinoids. The 9-cis β-carotene and Dunaliella lipid extract inhibited foam cell formation in the RAW264.7 cell line, similar to 9-cis retinoic acid. Furthermore, dietary enrichment with the algal powder in mice resulted in carotenoid accumulation in the peritoneal macrophages and in the inhibition of foam cell formation ex-vivo and in-vivo. We also found that the β-carotene cleavage enzyme β-carotene 15,15'-monooxygenase (BCMO1 is expressed and active in macrophages. Finally, 9-cis β-carotene, as well as the Dunaliella extract, activated the nuclear receptor RXR in hepa1-6 cells. These results indicate that dietary carotenoids, such as 9-cis β-carotene, accumulate in macrophages and can be locally cleaved by endogenous BCMO1 to form 9-cis retinoic acid and other retinoids. Subsequently, these retinoids activate the nuclear receptor RXR that, along with additional nuclear receptors, can affect various metabolic pathways, including those involved in foam cell formation and atherosclerosis.

  4. Dynasore, a dynamin inhibitor, inhibits Trypanosoma cruzi entry into peritoneal macrophages.

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    Emile S Barrias

    Full Text Available BACKGROUND: Trypanosoma cruzi is an intracellular parasite that, like some other intracellular pathogens, targets specific proteins of the host cell vesicular transport machinery, leading to a modulation of host cell processes that results in the generation of unique phagosomes. In mammalian cells, several molecules have been identified that selectively regulate the formation of endocytic transport vesicles and the fusion of such vesicles with appropriate acceptor membranes. Among these, the GTPase dynamin plays an important role in clathrin-mediated endocytosis, and it was recently found that dynamin can participate in a phagocytic process. METHODOLOGY/PRINCIPAL FINDINGS: We used a compound called dynasore that has the ability to block the GTPase activity of dynamin. Dynasore acts as a potent inhibitor of endocytic pathways by blocking coated vesicle formation within seconds of its addition. Here, we investigated whether dynamin is involved in the entry process of T. cruzi in phagocytic and non-phagocytic cells by using dynasore. In this aim, peritoneal macrophages and LLC-MK2 cells were treated with increasing concentrations of dynasore before interaction with trypomastigotes, amastigotes or epimastigotes. We observed that, in both cell lines, the parasite internalization was drastically diminished (by greater than 90% in LLC-MK2 cells and 70% in peritoneal macrophages when we used 100 microM dynasore. The T. cruzi adhesion index, however, was unaffected in either cell line. Analyzing these interactions by scanning electron microscopy and comparing peritoneal macrophages to LLC-MK2 cells revealed differences in the stage at which cell entry was blocked. In LLC-MK2 cells, this blockade is observed earlier than it is in peritoneal macrophages. In LLC-MK2 cells, the parasites were only associated with cellular microvilli, whereas in peritoneal macrophages, trypomastigotes were not completely engulfed by a host cell plasma membrane. CONCLUSIONS/SIGNIFICANCE

  5. The new 4-O-methylhonokiol analog GS12021 inhibits inflammation and macrophage chemotaxis: role of AMP-activated protein kinase α activation.

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    Sora Kim

    Full Text Available Preventing pathologic tissue inflammation is key to treating obesity-induced insulin resistance and type 2 diabetes. Previously, we synthesized a series of methylhonokiol analogs and reported that compounds with a carbamate structure had inhibitory function against cyclooxygenase-2 in a cell-free enzyme assay. However, whether these compounds could inhibit the expression of inflammatory genes in macrophages has not been investigated. Here, we found that a new 4-O-methylhonokiol analog, 3',5-diallyl-4'-methoxy-[1,1'-biphenyl]-2-yl morpholine-4-carboxylate (GS12021 inhibited LPS- or TNFα-stimulated inflammation in macrophages and adipocytes, respectively. LPS-induced phosphorylation of nuclear factor-kappa B (NF-κB/p65 was significantly decreased, whereas NF-κB luciferase activities were slightly inhibited, by GS12021 treatment in RAW 264.7 cells. Either mitogen-activated protein kinase phosphorylation or AP-1 luciferase activity was not altered by GS12021. GS12021 increased the phosphorylation of AMP-activated protein kinase (AMPK α and the expression of sirtuin (SIRT 1. Inhibition of mRNA expression of inflammatory genes by GS12021 was abolished in AMPKα1-knockdown cells, but not in SIRT1 knockout cells, demonstrating that GS12021 exerts anti-inflammatory effects through AMPKα activation. The transwell migration assay results showed that GS12021 treatment of macrophages prevented the cell migration promoted by incubation with conditioned medium obtained from adipocytes. GS12021 suppression of p65 phosphorylation and macrophage chemotaxis were preserved in AMPKα1-knockdown cells, indicating AMPK is not required for these functions of GS12021. Identification of this novel methylhonokiol analog could enable studies of the structure-activity relationship of this class of compounds and further evaluation of its in vivo potential for the treatment of insulin-resistant states and other chronic inflammatory diseases.

  6. Inhibition of VDAC1 prevents Ca²⁺-mediated oxidative stress and apoptosis induced by 5-aminolevulinic acid mediated sonodynamic therapy in THP-1 macrophages.

    Science.gov (United States)

    Chen, Haibo; Gao, Weiwei; Yang, Yang; Guo, Shuyuan; Wang, Huan; Wang, Wei; Zhang, Shuisheng; Zhou, Qi; Xu, Haobo; Yao, Jianting; Tian, Zhen; Li, Bicheng; Cao, Wenwu; Zhang, Zhiguo; Tian, Ye

    2014-12-01

    Ultrasound combined with endogenous protoporphyrin IX derived from 5-aminolevulinic acid (ALA-SDT) is known to induce apoptosis in multiple cancer cells and macrophages. Persistent retention of macrophages in the plaque has been implicated in the pathophysiology and progression of atherosclerosis. Here we investigated the effects of inhibition of voltage-dependent anion channel 1 (VDAC1) on ALA-SDT-induced THP-1 macrophages apoptosis. Cells were pre-treated with VDAC1 inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) disodium salt for 1 h or downregulated VDAC1 expression by small interfering RNA and exposed to ultrasound. Cell viability was assessed by MTT assay, and cell apoptosis along with necrosis was evaluated by Hoechst 33342/propidium iodide staining and flow cytometry. Levels of cytochrome c release was assessed by confocal microscope and Western blot. The levels of full length caspases, caspase activation, and VDAC isoforms were analyzed by Western blot. Intracellular reactive oxygen species generation, mitochondrial membrane permeability, and intracellular Ca(2+) [Ca(2+)]i levels were measured with fluorescent probes. We confirmed that the pharmacological inhibition of VDAC1 by DIDS notably prevented ALA-SDT-induced cell apoptosis in THP-1 macrophages. Additionally, DIDS significantly inhibited intracellular ROS generation and apoptotic biochemical changes such as inner mitochondrial membrane permeabilization, loss of mitochondrial membrane potential, cytochrome c release and activation of caspase-3 and caspase-9. Moreover, ALA-SDT elevated the [Ca(2+)]i levels and it was also notably reduced by DIDS. Furthermore, both of intracellular ROS generation and cell apoptosis were predominately inhibited by Ca(2+) chelating reagent BAPTA-AM. Intriguingly, ALA-treatment markedly augmented VDAC1 protein levels exclusively, and the downregulation of VDAC1 expression by specific siRNA also significantly abolished cell apoptosis. Altogether, these

  7. Echinacea Species and Alkamides Inhibit Prostaglandin E2 Production in RAW264.7 Mouse Macrophage Cells

    Science.gov (United States)

    LaLone, Carlie A.; Hammer, Kimberly D. P.; Wu, Lankun; Bae, Jaehoon; Leyva, Norma; Liu, Yi; Solco, Avery K. S.; Kraus, George A.; Murphy, Patricia A.; Wurtele, Eve S.; kim, Ok-Kyung; Seo, Kwon; Widrlechner, Mark P.; Birt, Diane F.

    2008-01-01

    Inhibition of prostaglandin E2 (PGE2) production in lipopolysaccharide-stimulated RAW264.7 mouse macrophage cells was assessed with an enzyme immunoassay following treatments with Echinacea extracts or synthesized alkamides. Results indicated that ethanol extracts diluted in media to a concentration of 15 μg/mL from E. angustifolia, E. pallida, E. simulata, and E. sanguinea significantly inhibited PGE2 production. In further studies, PGE2 production was significantly reduced by all synthesized alkamides assayed at 50 μM, by Bauer alkamides 8, 12A analogue, and 14, Chen alkamide 2, and Chen alkamide 2 analogue at 25 μM and by Bauer alkamide 14 at 10 μM. Cytotoxicity did not play a role in the noted reduction of PGE2 production in either the Echinacea extracts or synthesized alkamides. High-performance liquid chromatography analysis identified individual alkamides present at concentrations below 2.8 μM in the extracts from the six Echinacea species (15 μg/mL crude extract). Because active extracts contained Echinacea in a synergistic or additive manner. PMID:17696440

  8. Inhibition of EMMPRIN and MMP-9 Expression by Epigallocatechin-3-Gallate through 67-kDa Laminin Receptor in PMA-Induced Macrophages

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    Qi-Ming Wang

    2016-11-01

    Full Text Available Background/Aims: It is well documented that overexpression of EMMPRIN (extracellular matrix metalloproteinase inducer and MMPs (matrix metalloproteinases by monocytes/macrophages plays an important role in atherosclerotic plaque rupture. Green tea polyphenol epigallocatechin-3-gallate (EGCG has a variety of pharmacological properties and exerts cardiovascular protective effects. Recently, the 67-kD laminin receptor (67LR has been identified as a cell surface receptor of EGCG. The aim of the present study was to evaluate the effects of EGCG on the expression of EMMPRIN and MMP-9 in PMA-induced macrophages, and the potential mechanisms underlying its effects. Methods: Human monocytic THP-1 cells were induced to differentiate into macrophages with phorbol 12-myristate 13-acetate (PMA. Protein expression and MMP-9 activity were assayed by Western blot and Gelatin zymography, respectively. Real-time PCR was used to examine EMMPRIN and MMP-9 mRNA expression. Results: We showed that EGCG (10-50µmol/L significantly inhibited the expression of EMMPRIN and MMP-9 and activation of extracellular signal-regulated kinase 1/2 (ERK1/2, p38 and c-Jun N-terminal kinase (JNK in PMA-induced macrophages. Downregulation of EMMPRIN by gene silencing hindered PMA-induced MMP-9 secretion and expression, indicating an important role of EMMPRIN in the inhibition of MMP-9 by EGCG. Moreover, 67LR was involved in EGCG-mediated suppression of EMMPRIN and MMP-9 expression. Anti-67LR antibody treatment led to abrogation of the inhibitory action of EGCG on the expression of EMMPRIN and MMP-9 and activation of ERK1/2, p38, and JNK. Conclusion: Our results indicate that EGCG restrains EMMPRIN and MMP-9 expression via 67LR in PMA-induced macrophages, which also suggests that EGCG may be a possible therapeutic agent for stabilizing atherosclerotic plaque.

  9. Piperine Inhibits the Activities of Platelet Cytosolic Phospholipase A2 and Thromboxane A2 Synthase without Affecting Cyclooxygenase-1 Activity: Different Mechanisms of Action Are Involved in the Inhibition of Platelet Aggregation and Macrophage Inflammatory Response

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    Dong Ju Son

    2014-08-01

    Full Text Available PURPOSE: Piperine, a major alkaloid of black pepper (Piper nigrum and long pepper (Piper longum, was shown to have anti-inflammatory activity through the suppression of cyclooxygenase (COX-2 gene expression and enzyme activity. It is also reported to exhibit anti-platelet activity, but the mechanism underlying this action remains unknown. In this study, we investigated a putative anti-platelet aggregation mechanism involving arachidonic acid (AA metabolism and how this compares with the mechanism by which it inhibits macrophage inflammatory responses; METHODS: Rabbit platelets and murine macrophage RAW264.7 cells were treated with piperine, and the effect of piperine on the activity of AA-metabolizing enzymes, including cytosolic phospholipase A2 (cPLA2, COX-1, COX-2, and thromboxane A2 (TXA2 synthase, as well as its effect on AA liberation from the plasma membrane components, were assessed using isotopic labeling methods and enzyme immunoassay kit; RESULTS: Piperine significantly suppressed AA liberation by attenuating cPLA2 activity in collagen-stimulated platelets. It also significantly inhibited the activity of TXA2 synthase, but not of COX-1, in platelets. These results suggest that piperine inhibits platelet aggregation by attenuating cPLA2 and TXA2 synthase activities, rather than through the inhibition of COX-1 activity. On the other hand, piperine significantly inhibited lipopolysaccharide-induced generation of prostaglandin (PGE2 and PGD2 in RAW264.7 cells by suppressing the activity of COX-2, without effect on cPLA2; CONCLUSION: Our findings indicate that piperine inhibits platelet aggregation and macrophage inflammatory response by different mechanisms.

  10. Coeliac disease autoantibodies mediate significant inhibition of tissue transglutaminase.

    LENUS (Irish Health Repository)

    Byrne, Greg

    2012-02-01

    The detection of antibodies directed against tissue transglutaminase (tTG) in serum is a sensitive and specific test for suspected coeliac disease. tTG is a ubiquitous, multifunctional enzyme that has been implicated in many important physiological processes as well as the site-specific deamidation of glutamine residues in gluten-derived peptides. This modification of gluten peptides facilitates their binding to HLA-DQ2, which results in amplification of the T-cell response to gluten. The purpose of this study was to investigate the possibility that patient IgA autoantibodies directed against tTG interfere with the crosslinking activity of the enzyme. IgA autoantibodies against tTG were isolated\\/depleted from patient serum and tested for their capacity to interfere with tTG activity in vitro using a sensitive fluorescence-based activity assay. We have demonstrated that autoantibodies cause significant inhibition of tTG-mediated crosslinking at equimolar and 2:1 ratios of antibody to enzyme.

  11. Ethanol extract of Elaeocarpus petiolatus inhibits lipopolysaccharide-induced inflammation in macrophage cells.

    Science.gov (United States)

    Kwon, Ok-Kyoung; Ahn, Kyung-Seop; Park, Ji-Won; Jang, Ha-Young; Joung, Hyouk; Lee, Hyeong-Kyu; Oh, Sei-Ryang

    2012-04-01

    Elaeocarpus petiolatus is known to exert active oxygen scavenging, anti-aging, and whitening actions. However, the biological effects of E. petiolatus on inflammation and the underlying mechanisms are yet to be established. In the present study, we investigated the anti-inflammatory effects of the ethanol extract from E. petiolatus (EPE) bark in murine Raw264.7 macrophages stimulated with lipopolysaccharide (LPS). EPE inhibited the production of PGE(2), TNF-α, and IL-1β in a dose-dependent manner in Raw264.7 cells stimulated with LPS. The decrease in PGE(2) production was correlated with reduced COX-2 expression. Furthermore, EPE suppressed the phosphorylation of extracellular signal-related kinases (ERK), c-Jun N-terminal kinase (JNK), and p38 as well as translocation of the NF-κB p65 subunit from the cytosol to nucleus. Our results suggest that EPE exerts anti-inflammatory activity through inhibition of inflammatory mediators, such as PGE(2), TNF-α, and IL-1β, and downregulation of COX-2 via suppression of NF-κB translocation and phosphorylation of ERK, JNK, and p38 in LPS-stimulated Raw264.7 cells.

  12. Neoagaro-oligosaccharide monomers inhibit inflammation in LPS-stimulated macrophages through suppression of MAPK and NF-κB pathways

    Science.gov (United States)

    Wang, Wei; Liu, Pei; Hao, Cui; Wu, Lijuan; Wan, Wenjin; Mao, Xiangzhao

    2017-01-01

    Neoagaro-oligosaccharides derived from agarose have been demonstrated to possess a variety of biological activities, such as anti-bacteria and anti-oxidative activities. In this study, we mainly explored the inhibitory effects and the mechanisms of neoagaro-oligosaccharide monomers against LPS-induced inflammatory responses in mouse macrophage RAW264.7 cells. The results indicated that neoagaro-oligosaccharide monomers especially neoagarotetraose could significantly reduce the production and release of NO in LPS-induced macrophages. Neoagarotetraose significantly suppressed the expression and secretion of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines such as TNF-α and IL-6. The inhibition mechanisms may be associated with the inhibition of the activation of p38MAPK, Ras/MEK/ERK and NF-κB signaling pathways. Thus, neoagarotetraose may attenuate the inflammatory responses through downregulating the MAPK and NF-κB signaling pathways in LPS-stimulated macrophages. In summary, the marine-derived neoagaro-oligosaccharide monomers merit further investigation as novel anti-inflammation agents in the future. PMID:28266652

  13. Early diagnosis of acute renal allograft rejection: efficacy of macrophage migration inhibition test as an immunological diagnosis

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    Orita,Kunzo

    1977-06-01

    Full Text Available 1. Three cases of acute rejection were detected by macrophage migration inhibition tests (MIT conducted directly on seven patients who had received renal allografts. The macrophage migration inhibitory factor (MIF activity was positive in all cases 1-2 days before the appearance of acute rejection. 2. After the administration of a high dose of Solu-Medrol (1g/day for 3 days to suppress the acute rejection, MIF activity recovered to its normal level 3 days later. These findings seem to indicate that MIT yields immunologically useful criteria for the early detection of an acute rejection.

  14. Homocysteine Triggers Inflammatory Responses in Macrophages through Inhibiting CSE-H2S Signaling via DNA Hypermethylation of CSE Promoter

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    Jiao-Jiao Li

    2015-06-01

    Full Text Available Hyperhomocysteinemia (HHcy is an independent risk factor of atherosclerosis and other cardiovascular diseases. Unfortunately, Hcy-lowering strategies were found to have limited effects in reducing cardiovascular events. The underlying mechanisms remain unclear. Increasing evidence reveals a role of inflammation in the pathogenesis of HHcy. Homocysteine (Hcy is a precursor of hydrogen sulfide (H2S, which is formed via the transsulfuration pathway catalyzed by cystathionine β-synthase and cystathionine γ-lyase (CSE and serves as a novel modulator of inflammation. In the present study, we showed that methionine supplementation induced mild HHcy in mice, associated with the elevations of TNF-α and IL-1β in the plasma and reductions of plasma H2S level and CSE expression in the peritoneal macrophages. H2S-releasing compound GYY4137 attenuated the increases of TNF-α and IL-1β in the plasma of HHcy mice and Hcy-treated raw264.7 cells while CSE inhibitor PAG exacerbated it. Moreover, the in vitro study showed that Hcy inhibited CSE expression and H2S production in macrophages, accompanied by the increases of DNA methyltransferase (DNMT expression and DNA hypermethylation in cse promoter region. DNMT inhibition or knockdown reversed the decrease of CSE transcription induced by Hcy in macrophages. In sum, our findings demonstrate that Hcy may trigger inflammation through inhibiting CSE-H2S signaling, associated with increased promoter DNA methylation and transcriptional repression of cse in macrophages.

  15. Salvianic acid A inhibits induction of inflammatory mediators by blocking Nuclear Factor-kB activation in macrophages

    Institute of Scientific and Technical Information of China (English)

    YUAN Jun; YAO Ji-hong; ZHOU Qin

    2008-01-01

    Objective To investigate the anti-inflammation effect and possible mechanism of Salvianic acid A (SAA) in mouse peritoneal macrophages. Methods Peritoneal macrophages were obtained from BALB/c mice. LPS induced nitric oxide (NO), tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) in supernatant, protein expression of inducible nitric oxide synthase (iNOS), matrix metalloproteinase-9 (MMP-9) and activation of nuclear factor-kappa B (NF-kB) in the extract were measured. Results SAA strongly inhibited the excessive production of NO, TNF-α and IL-6 in LPS-induced peritoneal macrophages in a concentration-dependent manner and blocked the expression of iNOS and MMP-9. Treatment with LPS alone increased the translocation of NF-kB (1065) from cytosol to the nucleus, but the SAA inhibited the translocation of NF-kB (p65). Conclusions The results showed that SAA had strong anti-inflammatory effects in LPS-stimulated peritoneal macrophages. The important mechanism is due to its inhibition of NF-kB activation.

  16. Rosiglitazone inhibits expression of acyl-coenzyme A:cholesterol acyltransferase-1 in THP-1 macrophages induced by advanced glycation end-products

    Institute of Scientific and Technical Information of China (English)

    Yang Qihong; Xu Qiang; Zhang Hong; Si Liangyi

    2008-01-01

    Objective: To investigate the effects of rosiglitazone, a synthetic ligand of peroxisome proliferators-activated receptor gamma (PPARγ), on the expression of acyl-coenzyme A: cholesterol acyltransferase-1 (ACAT-1) in phorbol myristate acetate (PMA)-pretreated THP-1 cells after the inducement of advanced glycation end products (AGEs). Methods: After THP-1 cells were cultured in the presence of 0.1 umol/L PMA for 72 h to induce phagocytic differentiation, the obtained THP-1 macrophages were treated with rosiglitazone for 4 h at different concentrations (1,5 or 10 μmol/L) and then exposed to AGEs-modified bovine serum albumin (AGEs-BSA) for 24 h at a concentration of 200 mg/L. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis were performed to detect the mRNA and protein expressions of ACAT-1 respectively. Results: Administration of AGEs-BSA (200 mg/L) into the THP-1 macrophages resulted in up-regulation of ACAT-1 at mRNA and protein levels when compared with the expressions in macrophages incubated with serum-free RPM11640. Pretreatment of rosiglitazone inhibited significantly the increased expression of ACAT-1 induced by AGEs-BSA in a concentration-dependent manner. Conclusion: PPARγ activation by rosiglitazone down-regulates ACAT-1 expression induced by AGEs in THP-1 macrophages, which might provide a new way for treating atherogenesis in diabetic patients.

  17. Functional significance of macrophage-derived exosomes in inflammation and pain.

    Science.gov (United States)

    McDonald, Marguerite K; Tian, Yuzhen; Qureshi, Rehman A; Gormley, Michael; Ertel, Adam; Gao, Ruby; Aradillas Lopez, Enrique; Alexander, Guillermo M; Sacan, Ahmet; Fortina, Paolo; Ajit, Seena K

    2014-08-01

    Exosomes, secreted microvesicles transporting microRNAs (miRNAs), mRNAs, and proteins through bodily fluids, facilitate intercellular communication and elicit immune responses. Exosomal contents vary, depending on the source and the physiological conditions of cells, and can provide insights into how cells and systems cope with physiological perturbations. Previous analysis of circulating miRNAs in patients with complex regional pain syndrome (CRPS), a debilitating chronic pain disorder, revealed a subset of miRNAs in whole blood that are altered in the disease. To determine functional consequences of alterations in exosomal biomolecules in inflammation and pain, we investigated exosome-mediated information transfer in vitro, in a rodent model of inflammatory pain, and in exosomes from patients with CRPS. Mouse macrophage cells stimulated with lipopolysaccharides secrete exosomes containing elevated levels of cytokines and miRNAs that mediate inflammation. Transcriptome sequencing of exosomal RNA revealed global alterations in both innate and adaptive immune pathways. Exosomes from lipopolysaccharide-stimulated cells were sufficient to cause nuclear factor-κB activation in naive cells, indicating functionality in recipient cells. A single injection of exosomes attenuated thermal hyperalgesia in a murine model of inflammatory pain, suggesting an immunoprotective role for macrophage-derived exosomes. Macrophage-derived exosomes carry a protective signature that is altered when secreting cells are exposed to an inflammatory stimulus. We also show that circulating miRNAs altered in patients with complex regional pain syndrome are trafficked by exosomes. With their systemic signaling capabilities, exosomes can induce pleiotropic effects potentially mediating the multifactorial pathology underlying chronic pain, and should be explored for their therapeutic utility.

  18. Ketamine inhibits tumor necrosis factor secretion by RAW264.7 murine macrophages stimulated with antibiotic-exposed strains of community-associated, methicillin-resistant Staphylococcus aureus

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    Aguirre Carlos

    2011-01-01

    Full Text Available Abstract Background Infections caused by community-associated strains of methicillin-resistant Staphylococcus aureus (CA-MRSA are associated with a marked and prolonged host inflammatory response. In a sepsis simulation model, we tested whether the anesthetic ketamine inhibits the macrophage TNF response to antibiotic-exposed CA-MRSA bacteria via its antagonism of N-methyl-D-aspartate (NMDA receptors. RAW264.7 cells were stimulated for 18 hrs with 105 to 107 CFU/mL inocula of either of two prototypical CA-MRSA isolates, USA300 strain LAC and USA400 strain MW2, in the presence of either vancomycin or daptomycin. One hour before bacterial stimulation, ketamine was added with or without MK-801 (dizocilpine, a chemically unrelated non-competitive NMDA receptor antagonist, APV (D-2-amino-5-phosphono-valerate, a competitive NMDA receptor antagonist, NMDA, or combinations of these agents. Supernatants were collected and assayed for TNF concentration by ELISA. Results RAW264.7 cells exposed to either LAC or MW2 in the presence of daptomycin secreted less TNF than in the presence of vancomycin. The addition of ketamine inhibited macrophage TNF secretion after stimulation with either of the CA-MRSA isolates (LAC, MW2 in the presence of either antibiotic. The NMDA inhibitors, MK-801 and APV, also suppressed macrophage TNF secretion after stimulation with either of the antibiotic-exposed CA-MRSA isolates, and the effect was not additive or synergistic with ketamine. The addition of NMDA substrate augmented TNF secretion in response to the CA-MRSA bacteria, and the addition of APV suppressed the effect of NMDA in a dose-dependent fashion. Conclusions Ketamine inhibits TNF secretion by MRSA-stimulated RAW264.7 macrophages and the mechanism likely involves NMDA receptor antagonism. These findings may have therapeutic significance in MRSA sepsis.

  19. Inhibition of NOS-NO System Prevents Autoimmune Orchitis Development in Rats: Relevance of NO Released by Testicular Macrophages in Germ Cell Apoptosis and Testosterone Secretion.

    Directory of Open Access Journals (Sweden)

    Sabrina Jarazo Dietrich

    Full Text Available Although the testis is considered an immunoprivileged organ it can orchestrate immune responses against pathological insults such as infection and trauma. Experimental autoimmune orchitis (EAO is a model of chronic inflammation whose main histopathological features it shares with human orchitis. In EAO an increased number of macrophages infiltrate the interstitium concomitantly with progressive germ cell degeneration and impaired steroidogenesis. Up-regulation of nitric oxide (NO-NO synthase (NOS system occurs, macrophages being the main producers of NO.The aim of our study was to evaluate the role of NO-NOS system in orchitis development and determine the involvement of NO released by testicular macrophages on germ cell apoptosis and testosterone secretion.EAO was induced in rats by immunization with testicular homogenate and adjuvants (E group and a group of untreated normal rats (N was also studied. Blockage of NOS by i.p. injection of E rats with a competitive inhibitor of NOS, L-NAME (8mg/kg, significantly reduced the incidence and severity of orchitis and lowered testicular nitrite content. L-NAME reduced germ cell apoptosis and restored intratesticular testosterone levels, without variations in serum LH. Co-culture of N testicular fragments with testicular macrophages obtained from EAO rats significantly increased germ cell apoptosis and testosterone secretion, whereas addition of L-NAME lowered both effects and reduced nitrite content. Incubation of testicular fragments from N rats with a NO donor DETA-NOnoate (DETA-NO induced germ cell apoptosis through external and internal apoptotic pathways, an effect prevented by N-acetyl-L-cysteine (NAC. DETA-NO inhibited testosterone released from Leydig cells, whereas NAC (from 2.5 to 15 mM did not prevent this effect.We demonstrated that NO-NOS system is involved in the impairment of testicular function in orchitis. NO secreted mainly by testicular macrophages could promote oxidative stress

  20. Angptl4 protects against severe proinflammatory effects of saturated fat by inhibiting fatty acid uptake into mesenteric lymph node macrophages.

    Science.gov (United States)

    Lichtenstein, Laeticia; Mattijssen, Frits; de Wit, Nicole J; Georgiadi, Anastasia; Hooiveld, Guido J; van der Meer, Roelof; He, Yin; Qi, Ling; Köster, Anja; Tamsma, Jouke T; Tan, Nguan Soon; Müller, Michael; Kersten, Sander

    2010-12-01

    Dietary saturated fat is linked to numerous chronic diseases, including cardiovascular disease. Here we study the role of the lipoprotein lipase inhibitor Angptl4 in the response to dietary saturated fat. Strikingly, in mice lacking Angptl4, saturated fat induces a severe and lethal phenotype characterized by fibrinopurulent peritonitis, ascites, intestinal fibrosis, and cachexia. These abnormalities are preceded by a massive acute phase response induced by saturated but not unsaturated fat or medium-chain fat, originating in mesenteric lymph nodes (MLNs). MLNs undergo dramatic expansion and contain numerous lipid-laden macrophages. In peritoneal macrophages incubated with chyle, Angptl4 dramatically reduced foam cell formation, inflammatory gene expression, and chyle-induced activation of ER stress. Induction of macrophage Angptl4 by fatty acids is part of a mechanism that serves to reduce postprandial lipid uptake from chyle into MLN-resident macrophages by inhibiting triglyceride hydrolysis, thereby preventing macrophage activation and foam cell formation and protecting against progressive, uncontrolled saturated fat-induced inflammation. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Inhibition of herpes simplex virus multiplication by activated macrophages: a role for arginase?

    Science.gov (United States)

    Wildy, P; Gell, P G; Rhodes, J; Newton, A

    1982-01-01

    Proteose-peptone-activated mouse macrophages can prevent productive infection by herpes simplex virus in neighboring cells in vitro whether or not those cells belong to the same animal species. The effect does not require contact between the macrophages and the infected cells, may be prevented by adding extra arginine to the medium, and may be reversed when extra arginine is added 24 h after the macrophages. Arginase activity was found both intracellularly and released from the macrophages. The extracellular enzyme is quite stable; 64% activity was found after 48 h of incubation at 37 degrees C in tissue culture medium. No evidence was found that the inefficiency of virus replication in macrophages was due to self-starvation by arginase. As might be predicted macrophages can, by the same mechanism, limit productive infection by vaccinia virus. PMID:6286497

  2. Inhibition of HIV-1 replication in alveolar macrophages by adenovirus gene transfer vectors.

    Science.gov (United States)

    Rice, Joshua; Connor, Ruth; Worgall, Stefan; Moore, John P; Leopold, Philip L; Kaner, Robert J; Crystal, Ronald G

    2002-08-01

    To assess the hypothesis that infection of alveolar macrophages (AM) with adenovirus (Ad) gene transfer vectors might prevent subsequent human immunodeficiency virus (HIV)-1 replication in AM, AM isolated from normal volunteers were infected with increasing doses of first generation (E1(-)) Ad vectors, followed 72 h later by infection with HIV-1(JRFL), an R5/M-tropic strain that preferentially uses the CCR5 coreceptor. As a measure of HIV-1 replication, p24 Ag was quantified by enzyme-linked imunosorbent assay in supernatants on Days 4 to 14 after HIV-1infection. Pretreatment of the AM with an Ad vector resulted in a dose- and time-dependent suppression of subsequent HIV-1 replication. The Ad vector inhibition of HIV-1 replication was independent of the transgene in the Ad vector expression cassette and E4 genes in the Ad backbone. Moreover, it did not appear to be secondary to a soluble factor released by the AM, nor was it overridden by the concomitant transfer of the CCR5 or CXCR4 receptors to the AM before HIV-1 infection. These observations have implications regarding pulmonary host responses associated with HIV-1 infection, as well as possibly uncovering new therapeutic strategies against HIV-1 infection.

  3. Surface iron inhibits quartz-induced cytotoxic and inflammatory responses in alveolar macrophages.

    Science.gov (United States)

    Ghiazza, Mara; Scherbart, Agnes M; Fenoglio, Ivana; Grendene, Francesca; Turci, Francesco; Martra, Gianmario; Albrecht, Catrin; Schins, Roel P F; Fubini, Bice

    2011-01-14

    The mechanism of enhancement/inhibition of quartz toxicity induced by iron is still unclear. Here the amount of iron on a fibrogenic quartz (Qz) was increased by wet impregnation (Fe(NO(3))(3) 0.67 and 6.7 wt %). X-ray diffraction (XRD), XRF diffuse reflectance, UV-vis, and infrared (IR) spectroscopies revealed dispersed ferric ions, and hematite aggregates at the higher loading. Surface features relevant to pathogenicity and cell responses were compared not only to the original quartz but also to reference quartz DQ12. Surface charge (ζ-potential) was more negative on the original and low-loaded specimen than on the high-loaded one. DQ12 had a less negative ζ-potential than Qz, ascribed to the absence of aluminium present in Qz (1.7 wt %). All quartz specimens were able to generate HO(•) radicals, iron-loaded samples being more reactive than original quartz. Iron deposition inhibited the rupture of a C-H bond. All quartzes were phagocytized by alveolar macrophages (AMΦ cell line NR8383) to the same extent, irrespective of their surface state. Conversely, iron loading increased AMΦ viability (evaluated by cytotoxicity and induction of apoptosis). Qz was found to be much less cytotoxic than DQ12. The induction of oxidative stress and inflammatory responses (evaluated by HO-1 mRNA expression and TNF-α mRNA and protein expression) revealed a reduction in inflammogenicity upon iron loading and a more inflammogenic potency of DQ12 ascribed to undissociated SiOH interacting via H-bonding with cell membrane components. The results suggest that besides aluminium also iron at the quartz surface may have an inhibitory effect on adverse health responses.

  4. Sesamin inhibits macrophage-induced vascular endothelial growth factor and matrix metalloproteinase-9 expression and proangiogenic activity in breast cancer cells.

    Science.gov (United States)

    Lee, Chun-Chung; Liu, Ko-Jiunn; Wu, Yu-Chen; Lin, Sue-Jane; Chang, Ching-Chun; Huang, Tze-Sing

    2011-06-01

    Sesamin is a sesame component with antihypertensive and antioxidative activities and has recently aroused much interest in studying its potential anticancer application. Macrophage is one of the infiltrating inflammatory cells in solid tumor and may promote tumor progression via enhancement of tumor angiogenesis. In this study, we investigated whether sesamin inhibited macrophage-enhanced proangiogenic activity of breast cancer cell lines MCF-7 and MDA-MB-231. Using vascular endothelial cell capillary tube and network formation assays, both breast cancer cell lines exhibited elevated proangiogenic activities after coculture with macrophages or pretreatment with macrophage-conditioned medium. This elevation of proangiogenic activity was drastically suppressed by sesamin. Vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) induced by macrophages in both cell lines were also inhibited by sesamin. Nuclear levels of HIF-1α and NF-κB, important transcription factors for VEGF and MMP-9 expression, respectively, were obviously reduced by sesamin. VEGF induction by macrophage in MCF-7 cells was shown to be via ERK, JNK, phosphatidylinositol 3-kinase, and NF-κB-mediated pathways. These signaling molecules and additional p38(MAPK) were also involved in macrophage-induced MMP-9 expression. Despite such diverse pathways were induced by macrophage, only Akt and p38(MAPK) activities were potently inhibited by sesamin. Expression of interleukin (IL)-6, IL-8, and tumor necrosis factor-α were substantially increased and involved in macrophage-induced VEGF and MMP-9 mRNA expression in MCF-7 cells. Sesamin effectively inhibited the expression of these cytokines to avoid the reinforced induction of VEGF and MMP-9. In conclusion, sesamin potently inhibited macrophage-enhanced proangiogenic activity of breast cancer cells via inhibition of VEGF and MMP-9 induction.

  5. Mesenchymal stem cells alleviate atherosclerosis by elevating number and function of CD4(+)CD25 (+)FOXP3 (+) regulatory T-cells and inhibiting macrophage foam cell formation.

    Science.gov (United States)

    Wang, Zhi Xiao; Wang, Chong Quan; Li, Xiao Yan; Feng, Gao Ke; Zhu, Hong Ling; Ding, Yan; Jiang, Xue Jun

    2015-02-01

    Atherosclerosis is a chronic inflammatory disease characterized by the formation of plaques inside arteries, leading to narrowing and blockage. Potential therapeutic strategies include expanding the population of regulatory T-cells (Tregs) to enhance atheroprotective immunity, and inhibiting the formation of macrophage foam cells. Here, we studied the effect of bone marrow-derived mesenchymal stem cells (BM-MSCs) on atherosclerotic plaque formation in Apolipoprotein E(-/-) (ApoE-KO) mice, and elucidated the underlying mechanism. BM-MSCs isolated from 4 week-old ApoE-KO mice were evaluated by flow cytometry for expression of MSC-specific markers. Thirty eight week-old ApoE-KO mice were randomly divided into three experimental groups (n = 10 per group): 1. MSC group-received BM-MSCs intravenously; 2. Vehicle group-received DMEM; 3. Control group-did not receive any treatment. Administration of MSCs resulted in a marked decrease in the size of atherosclerotic plaques 3 months after treatment. In addition, the number and function of CD4(+)CD25(+)FOXP3(+) regulatory T-cells (Tregs) in cultured splenocytes, and the expression of FOXP3 at both mRNA and protein levels, was significantly increased in the MSC group. In vitro experiments further indicated that the formation of macrophage foam cells was inhibited by treatment with MSCs, accompanied by a significant downregulation in CD36 and scavenger receptor A (SRA). Our findings suggest that MSCs play an atheroprotective role by enhancing the number and function of Tregs and inhibiting the formation of macrophage foam cells. Hence, administration of MSCs to atherosclerotic patients might have significant clinical benefits.

  6. Liposomal phosphatidylserine inhibits tumor cytotoxicity of liver macrophages induced by muramyl dipeptide and lipopolysaccharide

    NARCIS (Netherlands)

    Daemen, T; Regts, J; Scherphof, GL

    1996-01-01

    Liposomes can very efficiently deliver immunomodulators to macrophages so as to induce tumor cytotoxicity. Liposomes most widely used for that purpose contain negatively charged lipids, in particular phosphatidylserine (PS), to enhance liposome uptake by the macrophages. We investigated the effect o

  7. Combination of n-3 polyunsaturated fatty acids reduces atherogenesis in apolipoprotein E-deficient mice by inhibiting macrophage activation.

    Science.gov (United States)

    Takashima, Akira; Fukuda, Daiju; Tanaka, Kimie; Higashikuni, Yasutomi; Hirata, Yoichiro; Nishimoto, Sachiko; Yagi, Shusuke; Yamada, Hirotsugu; Soeki, Takeshi; Wakatsuki, Tetsuzo; Taketani, Yutaka; Shimabukuro, Michio; Sata, Masataka

    2016-11-01

    Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are major components of n-3 polyunsaturated fatty acids (n-3 PUFAs) which inhibit atherogenesis, although few studies have examined the effects of the combination of EPA and DHA on atherogenesis. The aim of this study was to investigate whether DHA has additional anti-atherosclerotic effects when combined with EPA. Male 8-week-old apolipoprotein E-deficient (Apoe(-/-)) mice were fed a western-type diet supplemented with different amounts of EPA and DHA; EPA (2.5%, w/w), low-dose EPA + DHA (2.5%, w/w), or high-dose EPA + DHA (5%, w/w) for 20 weeks. The control group was fed a western-type diet containing no n-3 PUFA. Histological and gene expression analysis were performed in atherosclerotic lesions in the aorta. To address the mechanisms, RAW264.7 cells were used. All n-3 PUFA treatments significantly attenuated the development and destabilization of atherosclerotic plaques compared with the control. The anti-atherosclerotic effects were enhanced in the high-dose EPA + DHA group (p < 0.001), whereas the pure EPA group and low-dose EPA + DHA group showed similar results. EPA and DHA additively attenuated the expression of inflammatory molecules in RAW264.7 cells stimulated with LPS. DHA or EPA + DHA suppressed LPS-induced toll-like receptor 4 (TLR4) expression in lipid rafts on RAW264.7 cells (p < 0.05). Lipid raft disruption by methyl-β-cyclodextrin suppressed mRNA expression of inflammatory molecules in LPS-stimulated macrophages. n-3 PUFAs suppressed atherogenesis. DHA combined with EPA had additional anti-inflammatory effects and inhibited atherogenesis in Apoe(-/-) mice. The reduction of TLR4 expression in lipid rafts in macrophages by DHA might be involved in this mechanism, at least partially. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Nfkb1 inhibits LPS-induced IFN-β and IL-12 p40 production in macrophages by distinct mechanisms.

    Directory of Open Access Journals (Sweden)

    Xixing Zhao

    Full Text Available BACKGROUND: Nfkb1-deficient murine macrophages express higher levels of IFN-β and IL-12 p40 following LPS stimulation than control macrophages, but the molecular basis for this phenomenon has not been completely defined. Nfkb1 encodes several gene products including the NF-κB subunit p50 and its precursor p105. p50 is derived from the N-terminal of 105, and p50 homodimers can exhibit suppressive activity when overexpressed. The C-terminal region of p105 is necessary for LPS-induced ERK activation and it has been suggested that ERK activity inhibits both IFN-β and IL-12 p40 following LPS stimulation. However, the contributions of p50 and the C-terminal domain of p105 in regulating endogenous IFN-β(Ifnb and IL-12 p40 (Il12b gene expression in macrophages following LPS stimulation have not been directly compared. METHODOLOGY/PRINCIPAL FINDINGS: We have used recombinant retroviruses to express p105, p50, and the C-terminal domain of p105 (p105ΔN in Nfkb1-deficient murine bone marrow-derived macrophages at near endogenous levels. We found that both p50 and p105ΔN inhibited expression of Ifnb, and that inhibition of Ifnb by p105ΔN depended on ERK activation, because a mutant of p105ΔN (p105ΔNS930A that lacks a key serine necessary to support ERK activation failed to inhibit. In contrast, only p105ΔN but not p50 inhibited Il12b expression. Surprisingly, p105ΔNS930A retained inhibitory activity for Il12b, indicating that ERK activation was not necessary for inhibition. The differential effects of p105ΔNS930A on Ifnb and Il12b expression inversely correlated with the function of one of its binding partners, c-Rel. This raised the possibility that p105ΔNS930A influences gene expression by interfering with the function of c-Rel. CONCLUSIONS: These results demonstrate that Nfkb1 exhibits multiple gene-specific inhibitory functions following TLR stimulation of murine macrophages.

  9. Use of silver nanowires to determine thresholds for fibre length-dependent pulmonary inflammation and inhibition of macrophage migration in vitro

    Directory of Open Access Journals (Sweden)

    Schinwald Anja

    2012-12-01

    Full Text Available Abstract Background The objective of this study was to examine the threshold fibre length for the onset of pulmonary inflammation after aspiration exposure in mice to four different lengths of silver nanowires (AgNW. We further examined the effect of fibre length on macrophage locomotion in an in vitro wound healing assay. We hypothesised that exposure to longer fibres causes both increased inflammation and restricted mobility leading to impaired clearance of long fibres from the lower respiratory tract to the mucociliary escalator in vivo. Methods Nine week old female C57BL/6 strain mice were exposed to AgNW and controls via pharyngeal aspiration. The dose used in this study was equalised to fibre number and based on 50 μg/ mouse for AgNW14. To examine macrophage migration in vitro a wound healing assay was used. An artificial wound was created in a confluent layer of bone marrow derived macrophages by scraping with a pipette tip and the number of cells migrating into the wound was monitored microscopically. The dose was equalised for fibre number and based on 2.5 μg/cm2 for AgNW14. Results Aspiration of AgNW resulted in a length dependent inflammatory response in the lungs with threshold at a fibre length of 14 μm. Shorter fibres including 3, 5 and 10 μm elicited no significant inflammation. Macrophage locomotion was also restricted in a length dependent manner whereby AgNW in the length of ≥5 μm resulted in impaired motility in the wound closure assay. Conclusion We demonstrated a 14 μm cut-off length for fibre-induced pulmonary inflammation after aspiration exposure and an in vitro threshold for inhibition of macrophage locomotion of 5 μm. We previously reported a threshold length of 5 μm for fibre-induced pleural inflammation. This difference in pulmonary and pleural fibre- induced inflammation may be explained by differences in clearance mechanism of deposited fibres from the airspaces compared to the pleural space. Inhibition of

  10. Clinical and Biological Significance of Clonal Macrophage Detection in Hemophagocytic Syndrome

    Institute of Scientific and Technical Information of China (English)

    林雯; 肖燕; 费洪宝

    2002-01-01

    Summary: By using the method of clonal analysis the evidence to prove that Hemophagocytic syn drome (HPS) is reactive or malignant was investigated to probe into the pathogenesis of HPS and its relations with clinical prognosis. The macrophages abnormally proliferated in bone marrow were iso lated. Electrophoresis analysis was made after DNA extraction, enzyme restriction of human ardro gen receptor (HUMARA) genetic locus, and PCR amplification. In the 9 specimens, clonal prolifer ation was found in 2 cases and nonclonal proliferation in 7. Among the 7 cases of nonclonal prolifera tion, 3 were voluntarily discharged without clinical outcome, 2 cases fully recovered after 2-3 week treatment of large dose gamma globulin intravenous drip and hormone therapy, 1 case died at the 43th day after the hormone and anti-infection therapy, and one case was found to have granular leukoblast in peripheral blood after 3 weeks and diagnosed as having M2a after bone puncture. For the two patients with clonal proliferation, one obtained remission after chemotherapy and the other was died after 32 days without chemotherapy. It was concluded that there do exist clonal or malig nant proliferation in HPS, so not every case is reactive.

  11. Liposomal targeting of prednisolone phosphate to synovial lining macrophages during experimental arthritis inhibits M1 activation but does not favor M2 differentiation.

    Directory of Open Access Journals (Sweden)

    Wouter Hofkens

    Full Text Available BACKGROUND: To determine the effects of liposomal targeting of prednisolone phosphate (Lip-PLP to synovial lining macrophages on M1 and M2 polarization in vitro and during experimental arthritis. MATERIAL AND METHODS: Experimental arthritis (antigen and immune complex induced was elicited in mice and prednisolone containing liposomes were given systemically. Synovium was investigated using microarray analysis, RT-PCR and histology. Bone-marrow macrophages were stimulated towards M1 using LPS and IFNγ before treatment by PLP-liposomes. M1 and M2 markers were determined using RT-PCR. RESULTS: Microarray analysis of biopsies of inflamed synovium during antigen induced arthritis (AIA showed an increased M1 signature characterized by upregulation of IL-1β, IL-6 and FcγRI starting from day 1 and lasting up until day 7 after arthritis induction. The M2 signature remained low throughout the 7 day course of arthritis. Treatment of AIA with intravenously delivered Lip-PLP strongly suppressed joint swelling and synovial infiltration whereas colloidal gold containing liposomes exclusively targeted the macrophages within the inflamed synovial intima layer. In vitro studies showed that Lip-PLP phagocytosed by M1 macrophages resulted in a suppression of the M1 phenotype and induction of M2 markers (IL-10, TGF-β, IL-1RII, CD163, CD206 and Ym1. In vivo, Lip-PLP treatment strongly suppressed M1 markers (TNF-α, IL-1β, IL-6, IL-12p40, iNOS, FcγRI, Ciita and CD86 after local M1 activation of lining macrophages with LPS and IFN-γ and during experimental AIA and immune complex arthritis (ICA. In contrast, M2 markers were not significantly upregulated in antigen-induced arthritis and down regulated in immune complex arthritis. CONCLUSION: This study clearly shows that systemic treatment with PLP-liposomes selectively targets synovial lining macrophages and inhibits M1 activation. In contrast to in vitro findings, PLP-liposomes do not cause a shift of synovial

  12. Liposomal Targeting of Prednisolone Phosphate to Synovial Lining Macrophages during Experimental Arthritis Inhibits M1 Activation but Does Not Favor M2 Differentiation

    Science.gov (United States)

    Hofkens, Wouter; Schelbergen, Rik; Storm, Gert; van den Berg, Wim B.; van Lent, Peter L.

    2013-01-01

    Background To determine the effects of liposomal targeting of prednisolone phosphate (Lip-PLP) to synovial lining macrophages on M1 and M2 polarization in vitro and during experimental arthritis. Material and Methods Experimental arthritis (antigen and immune complex induced) was elicited in mice and prednisolone containing liposomes were given systemically. Synovium was investigated using microarray analysis, RT-PCR and histology. Bone–marrow macrophages were stimulated towards M1 using LPS and IFNγ before treatment by PLP-liposomes. M1 and M2 markers were determined using RT-PCR. Results Microarray analysis of biopsies of inflamed synovium during antigen induced arthritis (AIA) showed an increased M1 signature characterized by upregulation of IL-1β, IL-6 and FcγRI starting from day 1 and lasting up until day 7 after arthritis induction. The M2 signature remained low throughout the 7 day course of arthritis. Treatment of AIA with intravenously delivered Lip-PLP strongly suppressed joint swelling and synovial infiltration whereas colloidal gold containing liposomes exclusively targeted the macrophages within the inflamed synovial intima layer. In vitro studies showed that Lip-PLP phagocytosed by M1 macrophages resulted in a suppression of the M1 phenotype and induction of M2 markers (IL-10, TGF-β, IL-1RII, CD163, CD206 and Ym1). In vivo, Lip-PLP treatment strongly suppressed M1 markers (TNF-α, IL-1β, IL-6, IL-12p40, iNOS, FcγRI, Ciita and CD86) after local M1 activation of lining macrophages with LPS and IFN-γ and during experimental AIA and immune complex arthritis (ICA). In contrast, M2 markers were not significantly upregulated in antigen-induced arthritis and down regulated in immune complex arthritis. Conclusion This study clearly shows that systemic treatment with PLP-liposomes selectively targets synovial lining macrophages and inhibits M1 activation. In contrast to in vitro findings, PLP-liposomes do not cause a shift of synovial lining

  13. Activation of Cannabinoid Receptor 2 Ameliorates DSS-Induced Colitis through Inhibiting NLRP3 Inflammasome in Macrophages.

    Science.gov (United States)

    Ke, Ping; Shao, Bo-Zong; Xu, Zhe-Qi; Wei, Wei; Han, Bin-Ze; Chen, Xiong-Wen; Su, Ding-Feng; Liu, Chong

    2016-01-01

    Activation of cannabinoid receptor 2 (CB2R) ameliorates inflammation, but the underlying mechanism remains unclear. In the present study, we examined whether activation of CB2R could suppress the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome. In peritoneal macrophages isolated from C57BL/6 mice, LPS/DSS challenge for 24 h increased the expression of the components of NLRP3 inflammasome NLRP3, Casp-1 p20/Casp-1 p45 ratio, proIL-1β and IL-1β and also enhanced autophagy (LC3-II/LC3-I ratio, Beclin-1 and SQSTM1). Pretreatment of peritoneal macrophages with HU 308, a selective CB2R agonist, attenuated LPS/DSS-induced NLRP3 inflammasome activation, but further enhanced autophagy. In comparison with wild-type (WT) control, peritoneal macrophages from CB2R knockout (KO) mice had more robust NLRP3 inflammasome activation and attenuated autophagy upon LPS/DSS challenge. Knockdown autophagy-related gene 5 (Atg5) with a siRNA in peritoneal macrophages attenuated the inhibitory effects of HU 308 on LPS/DSS-induced NLRP3 inflammasome activation in vitro. In vivo, HU308 treatment attenuated DSS-induced colitis mice associated with reduced colon inflammation and inhibited NLRP3 inflammasome activation in wild-type mice. In CB2R KO mice, DSS-induced inflammation and NLRP3 inflammasome activation were more pronounced than those in WT control. Finally, we demonstrated that AMPK-mTOR-P70S6K signaling pathway was involved in this CB2R-mediated process. We conclude that activation of CB2R ameliorates DSS-induced colitis through enhancing autophagy that may inhibit NLRP3 inflammasome activation in macrophages.

  14. Novel anti-inflammatory chalcone derivatives inhibit the induction of nitric oxide synthase and cyclooxygenase-2 in mouse peritoneal macrophages.

    Science.gov (United States)

    Herencia, F; Ferrándiz, M L; Ubeda, A; Guillén, I; Dominguez, J N; Charris, J E; Lobo, G M; Alcaraz, M J

    1999-06-18

    In a previous work, we tested a series of chalcone derivatives as possible anti-inflammatory compounds. We now investigate the effects of three of those compounds, CHI, CH8 and CH12, on nitric oxide and prostanoid generation in mouse peritoneal macrophages stimulated with lipopolysaccharide and in the mouse air pouch injected with zymosan, where they showed a dose-dependent inhibition with inhibitory concentration 50% values in the microM range. This effect was not the consequence of a direct inhibitory action on enzyme activities. Our results demonstrated that chalcone derivatives inhibited de novo inducible nitric oxide synthase and cyclooxygenase-2 synthesis, being a novel therapeutic approach for inflammatory diseases.

  15. IKK2 inhibition using TPCA-1-loaded PLGA microparticles attenuates laser-induced choroidal neovascularization and macrophage recruitment.

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    Subhash Gaddipati

    Full Text Available The inhibition of NF-κB by genetic deletion or pharmacological inhibition of IKK2 significantly reduces laser-induced choroid neovascularization (CNV. To achieve a sustained and controlled intraocular release of a selective and potent IKK2 inhibitor, 2-[(aminocarbonylamino]-5-(4-fluorophenyl-3-thiophenecarboxamide (TPCA-1 (MW: 279.29, we developed a biodegradable poly-lactide-co-glycolide (PLGA polymer-delivery system to further investigate the anti-neovascularization effects of IKK2 inhibition and in vivo biosafety using laser-induced CNV mouse model. The solvent-evaporation method produced spherical TPCA-1-loaded PLGA microparticles characterized with a mean diameter of 2.4 ¼m and loading efficiency of 80%. Retrobulbar administration of the TPCA-1-loaded PLGA microparticles maintained a sustained drug level in the retina during the study period. No detectable TPCA-1 level was observed in the untreated contralateral eye. The anti-CNV effect of retrobulbarly administrated TPCA-1-loaded PLGA microparticles was assessed by retinal fluorescein leakage and isolectin staining methods, showing significantly reduced CNV development on day 7 after laser injury. Macrophage infiltration into the laser lesion was attenuated as assayed by choroid/RPE flat-mount staining with anti-F4/80 antibody. Consistently, laser induced expressions of Vegfa and Ccl2 were inhibited by the TPCA-1-loaded PLGA treatment. This TPCA-1 delivery system did not cause any noticeable cellular or functional toxicity to the treated eyes as evaluated by histology and optokinetic reflex (OKR tests; and no systemic toxicity was observed. We conclude that retrobulbar injection of the small-molecule IKK2 inhibitor TPCA-1, delivered by biodegradable PLGA microparticles, can achieve a sustained and controllable drug release into choroid/retina and attenuate laser-induced CNV development without causing apparent systemic toxicity. Our results suggest a potential clinical application of

  16. Paeoniflorin prevents hepatic fibrosis of Schistosomiasis japonica by inhibiting TGF-β1 production from macrophages in mice

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to investigate the effect of paeoniflorin (PAE)on hepatic fibrosis of mice with Schistosomiasis japonica in vivo and in vitro,a model of hepatic fibrosis caused by schistosomiasis was established in mice infected with cercariae of Schistosomajaponicum.Then,PAE was orally administered before and after praziquantel treatment and both therapeutics were given simultaneously at different time points after the infection.The concentration of serum hyaluronic acid(HA)was determined by radioimmunoassay(RIA).Hepatic granuloma and fibrosis were evaluated via HE and Masson staining.The expression of s-smooth muscle actin(α-SMA),transforming growth factor 131(TGF-β1)and collagen I(Col Ⅰ)protein was detected by immunohistochemistry.The effect of soluble egg antigen(SEA)and PAE on the production of TGF-131 from mouse peritoneal macrophages (PMφs)was investigated by RT-PCR,Western blotting and ELISA.The effect of TGF-β1 in optimum macrophage-conditioned medium(OPMCM)on the proliferation of hepatic stellate cells(HSCs)and collagen secretion from HSCs with anti-TGF-β1 antibody was explored by MTT assay and ELISA.The results show that PAE could significantly reduce the concentration of serum HA,the size of egg granuloma,the severity of hepatic fibrosis and the expression of α-SMA,TGF-β1 and Col I protein in the pre-treatment group.However,in sim-or post-treatment group,PAE did not have any significant therapeutic effect.TGF-β1 could be secreted from PMφs stimulated by SEA.Meanwhile,the production of TGF-β1 from PMφs could be depressed significantly by PAE in a concentration-dependent manner.TGF-β1 could promote the proliferation of HSCs and the secretion of collagens.In a word,PAE can prevent hepatic granuloma and fibrosis caused by schistosomiasis japonica through the inhibition of the secretion of TGF-β1 from PMφs,the proliferation and activation of HSCs and the secretion of collagens from HSCs.

  17. The MAPK ERK5, but not ERK1/2, inhibits the progression of monocytic phenotype to the functioning macrophage

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    Wang, Xuening [Department of Pathology and Laboratory Medicine, Rutgers, NJ Medical School, 185 South Orange Ave, Newark, NJ 07103 (United States); Pesakhov, Stella [Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, PO Box 653, 84105 Beer-Sheva (Israel); Harrison, Jonathan S [Department of Medicine, Rutgers, Robert Wood Johnson Medical School, New Brunswick, NJ 08903 (United States); Kafka, Michael; Danilenko, Michael [Department of Clinical Biochemistry and Pharmacology, Faculty of Health Sciences, Ben-Gurion University of the Negev, PO Box 653, 84105 Beer-Sheva (Israel); Studzinski, George P, E-mail: studzins@njms.rutgers.edu [Department of Pathology and Laboratory Medicine, Rutgers, NJ Medical School, 185 South Orange Ave, Newark, NJ 07103 (United States)

    2015-01-01

    Intracellular signaling pathways present targets for pharmacological agents with potential for treatment of neoplastic diseases, with some disease remissions already recorded. However, cellular compensatory mechanisms usually negate the initial success. For instance, attempts to interrupt aberrant signaling downstream of the frequently mutated ras by inhibiting ERK1/2 has shown only limited usefulness for cancer therapy. Here, we examined how ERK5, that overlaps the functions of ERK1/2 in cell proliferation and survival, functions in a manner distinct from ERK1/2 in human AML cells induced to differentiate by 1,25D-dihydroxyvitamin D{sub 3} (1,25D). Using inhibitors of ERK1/2 and of MEK5/ERK5 at concentrations specific for each kinase in HL60 and U937 cells, we observed that selective inhibition of the kinase activity of ERK5, but not of ERK1/2, in the presence of 1,25D resulted in macrophage-like cell morphology and enhancement of phagocytic activity. Importantly, this was associated with increased expression of the macrophage colony stimulating factor receptor (M-CSFR), but was not seen when M-CSFR expression was knocked down. Interestingly, inhibition of ERK1/2 led to activation of ERK5 in these cells. Our results support the hypothesis that ERK5 negatively regulates the expression of M-CSFR, and thus has a restraining function on macrophage differentiation. The addition of pharmacological inhibitors of ERK5 may influence trials of differentiation therapy of AML. - Highlights: • ERK5 has at least some functions in AML cells which are distinct from those of ERK1/2. • ERK5 activity negatively controls the expression of M-CSFR. • ERK5 retards the progression of differentiation from monocyte to functional macrophage.

  18. GABA and Topiramate Inhibit the Formation of Human Macrophage-Derived Foam Cells by Modulating Cholesterol-Metabolism-Associated Molecules

    Directory of Open Access Journals (Sweden)

    Ying Yang

    2014-04-01

    Full Text Available Aims: γ-aminobutyric acid (GABA, the principal inhibitory neurotransmitter, acts on GABA receptors to play an important role in the modulation of macrophage functions. The present study examined the effects of GABA and a GABA receptor agonist on modulating cholesterol-metabolism-associated molecules in human monocyte-derived macrophages (HMDMs. Methods: ORO stain, HPLC, qRT-PCR, Western blot and EMSA were carried out using HMDMs exposed to ox-LDL with or without GABAergic agents as the experimental model. Results: GABA and topiramate reduced the percentage of cholesterol ester in lipid-laden HMDMs by down-regulating SR-A, CD36 and LOX-1 expression and up-regulating ABCA1, ABCG1 and SR-BI expression in lipid-laden HMDMs. The production of TNF-a was decreased in GABA-and topiramate-treated lipid-laden HMDMs, and levels of interleukin (IL-6 did not change. The activation of two signaling pathways, p38MAPK and NF-γB, was repressed by GABA and topiramate in lipid-laden HMDMs. Conclusion: GABA and topiramate inhibit the formation of human macrophage-derived foam cells and may be a possibility for macrophage targeted therapy of atherosclerotic lesions.

  19. Phloretin promotes osteoclast apoptosis in murine macrophages and inhibits estrogen deficiency-induced osteoporosis in mice.

    Science.gov (United States)

    Lee, Eun-Jung; Kim, Jung-Lye; Kim, Yun-Ho; Kang, Min-Kyung; Gong, Ju-Hyun; Kang, Young-Hee

    2014-09-15

    Bone-remodeling imbalance induced by increased osteoclast formation and bone resorption is known to cause skeletal diseases such as osteoporosis. The reduction of estrogen levels at menopause is one of the strongest risk factors developing postmenopausal osteoporosis. This study investigated osteoprotective effects of the dihydrochalcone phloretin found in apple tree leaves on bone loss in ovariectomized (OVX) C57BL/6 female mice as a model for postmenopausal osteoporosis. OVX demoted bone mineral density (BMD) of mouse femurs, reduced serum 17β-estradiol level and enhanced serum receptor activator of NF-κB ligand (RANKL)/osteoprotegerin ratio with uterine atrophy. Oral administration of 10 mg/kg phloretin to OVX mice for 8 weeks improved such effects, compared to sham-operated mice. Phloretin attenuated TRAP activity and cellular expression of β3 integrin and carbonic anhydrase II augmented in femoral bone tissues of OVX mice. This study further examined that osteogenic activity of phloretin in RANKL-differentiated Raw 264.7 macrophages into mature osteoclasts. Phloretin at 1-20 μM stimulated Smac expression and capase-3 activation concurrently with nuclear fragmentation of multi-nucleated osteoclasts, indicating that this compound promoted osteoclast apoptosis. Consistently, phloretin enhanced bcl-2 induction but diminished bax expression. Furthermore, phloretin activated ASK-1-diverged JNK and p38 MAPK signaling pathways in mature osteoclasts, whereas it dose-dependently inhibited the RANKL-stimulated activation of ERK. Therefore, phloretin manipulated ASK-1-MAPK signal transduction leading to transcription of apoptotic genes. Phloretin was effective in preventing estrogen deficiency-induced osteoclastogenic resorption.

  20. DMPD: Low density lipoprotein oxidation and its pathobiological significance. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 9261091 Low density lipoprotein oxidation and its pathobiological significance. Ste...in oxidation and its pathobiological significance. PubmedID 9261091 Title Low density lipoprotein oxidation ...and its pathobiological significance. Authors Steinberg D. Publication J Biol Che

  1. An ethyl acetate fraction of Moringa oleifera Lam. Inhibits human macrophage cytokine production induced by cigarette smoke.

    Science.gov (United States)

    Kooltheat, Nateelak; Sranujit, Rungnapa Pankla; Chumark, Pilaipark; Potup, Pachuen; Laytragoon-Lewin, Nongnit; Usuwanthim, Kanchana

    2014-02-18

    Moringa oleifera Lam. (MO) has been reported to harbor anti-oxidation and anti-inflammatory activity and useful in the treatment of inflammatory diseases. However, despite these findings there has been little work done on the effects of MO on immune cellular function. Since macrophages, TNF and related cytokines play an important pathophysiologic role in lung damage induced by cigarette smoke, we examined the effects of MO on cigarette smoke extract (CSE)-induced cytokine production by human macrophages. An ethyl acetate fraction of MO (MOEF) was prepared from fresh leaves extract of Moringa and shown to consist of high levels of phenolic and antioxidant activities. Human monocyte derived macrophages (MDM) pre-treated with varying concentrations of MOEF showed decreased production of TNF, IL-6 and IL-8 in response to both LPS and CSE. The decrease was evident at both cytokine protein and mRNA levels. Furthermore, the extract inhibited the expression of RelA, a gene implicated in the NF-κB p65 signaling in inflammation. The findings highlight the ability of MOEF to inhibit cytokines (IL-8) which promote the infiltration of neutrophils into the lungs and others (TNF, IL-6) which mediate tissue disease and damage.

  2. An Ethyl Acetate Fraction of Moringa oleifera Lam. Inhibits Human Macrophage Cytokine Production Induced by Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Nateelak Kooltheat

    2014-02-01

    Full Text Available Moringa oleifera Lam. (MO has been reported to harbor anti-oxidation and anti-inflammatory activity and useful in the treatment of inflammatory diseases. However, despite these findings there has been little work done on the effects of MO on immune cellular function. Since macrophages, TNF and related cytokines play an important pathophysiologic role in lung damage induced by cigarette smoke, we examined the effects of MO on cigarette smoke extract (CSE—induced cytokine production by human macrophages. An ethyl acetate fraction of MO (MOEF was prepared from fresh leaves extract of Moringa and shown to consist of high levels of phenolic and antioxidant activities. Human monocyte derived macrophages (MDM pre-treated with varying concentrations of MOEF showed decreased production of TNF, IL-6 and IL-8 in response to both LPS and CSE. The decrease was evident at both cytokine protein and mRNA levels. Furthermore, the extract inhibited the expression of RelA, a gene implicated in the NF-κB p65 signaling in inflammation. The findings highlight the ability of MOEF to inhibit cytokines (IL-8 which promote the infiltration of neutrophils into the lungs and others (TNF, IL-6 which mediate tissue disease and damage.

  3. Lipoxin Inhibits Fungal Uptake by Macrophages and Reduces the Severity of Acute Pulmonary Infection Caused by Paracoccidioides brasiliensis

    Directory of Open Access Journals (Sweden)

    Laura R. R. Ribeiro

    2015-01-01

    Full Text Available Cysteinyl leukotrienes (CysLTs and lipoxins (LXs are lipid mediators that control inflammation, with the former inducing and the latter inhibiting this process. Because the role played by these mediators in paracoccidioidomycosis was not investigated, we aimed to characterize the role of CysLT in the pulmonary infection developed by resistant (A/J and susceptible (B10.A mice. 48 h after infection, elevated levels of pulmonary LTC4 and LXA4 were produced by both mouse strains, but higher levels were found in the lungs of susceptible mice. Blocking the CysLTs receptor by MTL reduced fungal loads in B10.A, but not in A/J mice. In susceptible mice, MLT treatment led to reduced influx of PMN leukocytes, increased recruitment of monocytes, predominant synthesis of anti-inflammatory cytokines, and augmented expression of 5- and 15-lipoxygenase mRNA, suggesting a prevalent LXA4 activity. In agreement, MTL-treated macrophages showed reduced fungal burdens associated with decreased ingestion of fungal cells. Furthermore, the addition of exogenous LX reduced, and the specific blockade of the LX receptor increased the fungal loads of B10.A macrophages. This study showed for the first time that inhibition of CysLTs signaling results in less severe pulmonary paracoccidioidomycosis that occurs in parallel with elevated LX activity and reduced infection of macrophages.

  4. SP600125 Attenuates Nicotine-Related Aortic Aneurysm Formation by Inhibiting Matrix Metalloproteinase Production and CC Chemokine-Mediated Macrophage Migration

    Directory of Open Access Journals (Sweden)

    Zhen-Zhen Guo

    2016-01-01

    Full Text Available Nicotine, a major chemical component of cigarettes, plays a pivotal role in the development of abdominal aortic aneurysm (AAA. c-Jun N-terminal kinase (JNK has been demonstrated to participate in elastase-induced AAA. This study aimed to elucidate whether the JNK inhibitor SP600125 can attenuate nicotine plus angiotensin II- (AngII- induced AAA formation and to assess the underlying molecular mechanisms. SP600125 significantly attenuated nicotine plus AngII-induced AAA formation. The expression of matrix metalloproteinase- (MMP- 2, MMP-9, monocyte chemoattractant protein- (MCP- 1, and regulated-on-activation, normal T-cells expressed and secreted (RANTES was significantly upregulated in aortic aneurysm lesions but inhibited by SP600125. In vitro, nicotine induced the expression of MCP-1 and RANTES in both RAW264.7 (mouse macrophage and MOVAS (mouse vascular smooth muscle cells in a dose-dependent manner; expression was upregulated by 0.5 ng/mL nicotine but strongly downregulated by 500 ng/mL nicotine. SP600125 attenuated the upregulation of MCP-1 and RANTES expression and subsequent macrophage migration. In conclusion, SP600125 attenuates nicotine plus AngII-induced AAA formation likely by inhibiting MMP-2, MMP-9, MCP-1, and RANTES. The expression of chemokines in MOVAS cells induced by nicotine has an effect on RAW264.7 migration, which is likely to contribute to the development of nicotine-related AAA.

  5. Gamma-tocotrienol attenuates high-fat diet-induced obesity and insulin resistance by inhibiting adipose inflammation and M1 macrophage recruitment.

    Science.gov (United States)

    Zhao, L; Kang, I; Fang, X; Wang, W; Lee, M A; Hollins, R R; Marshall, M R; Chung, S

    2015-03-01

    We have previously demonstrated that gamma tocotrienol (γT3) potently inhibits adipocyte hyperplasia in human adipose-derived stem cells (hASCs). In this study, our objective was to investigate the γT3 effects on early-onset obesity, inflammation and insulin resistance in vivo. Young C57BL/6J mice were fed a high-fat (HF) diet supplemented with 0.05% γT3 for 4 weeks. The concentrations of γT3 in plasma and adipose tissue were measured using high-performance liquid chromatography. Effects of γT3 on body weight gain, adipose volume, plasma levels of fasting glucose, insulin (enzyme-linked immunosorbent assay (ELISA)), proinflammatory cytokines (mouse cytokine array), insulin signaling (western blotting) and gene expression (quantitative real-time PCR, qPCR) in the liver and adipose tissue were examined. Influences of γT3 on [3H]-2-deoxyglucose uptake and lipopolysaccharide (LPS)-mediated NFκB signaling (western blotting) were assessed in hASCs. Effects of γT3 on macrophage M1/M2 activation were investigated using qPCR in mouse bone marrow-derived macrophages. After a 4-week treatment, γT3 accumulated in adipose tissue and reduced HF diet-induced weight gain in epididymal fat, mesenteric fat and the liver. Compared with HF diet-fed mice, HF+γT3-fed mice were associated with (1) decreased plasma levels of fasting glucose, insulin and proinflammatory cytokines, (2) improved glucose tolerance and (3) enhanced insulin signaling in adipose tissue. There were substantial decreases in macrophage specific markers, and monocyte chemoattractant protein-1, indicating that γT3 reduced the recruitment of adipose tissue macrophages (ATMs). In addition, γT3 treatment in human adipocytes resulted in (1) activation of insulin-stimulated glucose uptake and (2) a significant suppression of MAP kinase and NFκB activation. In parallel, γT3 treatment led to a reduction of LPS-mediated M1 macrophage polarization. Our results demonstrated that γT3 ameliorates HF diet

  6. The ligand-bound thyroid hormone receptor in macrophages ameliorates kidney injury via inhibition of nuclear factor-κB activities

    Science.gov (United States)

    Furuya, Fumihiko; Ishii, Toshihisa; Tamura, Shogo; Takahashi, Kazuya; Kobayashi, Hidetoshi; Ichijo, Masashi; Takizawa, Soichi; Kaneshige, Masahiro; Suzuki-Inoue, Katsue; Kitamura, Kenichiro

    2017-01-01

    In chronic kidney disease (CKD) patients, inflammation plays a pivotal role in the progression of renal fibrosis. Hypothyroidism is associated with an increased occurrence of atherosclerosis and inflammation, suggesting protective roles of thyroid hormones and their receptors against inflammatory processes. The contribution of thyroid hormone receptors to macrophage differentiation has not been well documented. Here, we focused on the endogenous thyroid hormone receptor α (TRα) in macrophages and examined the role of ligand-bound TRα in macrophage polarization-mediated anti-inflammatory effects. TRα-deficient irradiated chimeric mice showed exacerbated tubulointerstitial injury in a unilateral ureteral obstruction model. Compared with wild-type macrophages, macrophages isolated from the obstructed kidneys of mice lacking TRα displayed increased expression of proinflammatory cytokines that was accompanied by enhanced nuclear translocation of p65. Comparison of TRα-deficient bone marrow-derived macrophages with wild-type macrophages confirmed the propensity of the former cells to produce excessive IL-1β levels. Co-culture of these macrophages with renal epithelial cells induced more severe damage to the epithelial cells via the IL-1 receptor. Our findings indicate that ligand-bound TRα on macrophages plays a protective role in kidney inflammation through the inhibition of NF-κB pathways, possibly by affecting the pro- and anti-inflammatory balance that controls the development of CKD. PMID:28272516

  7. Cartilage inflammation and degeneration is enhanced by pro-inflammatory (M1) macrophages in vitro, but not inhibited directly by anti-inflammatory (M2) macrophages

    NARCIS (Netherlands)

    L. Utomo (Lizette); Y.M. Bastiaansen-Jenniskens (Yvonne); J.A.N. Verhaar (Jan); G.J.V.M. van Osch (Gerjo)

    2016-01-01

    textabstractObjective Macrophages play a crucial role in the progression of osteoarthritis (OA). Their phenotype may range from pro-inflammatory to anti-inflammatory. The aim of this study was to evaluate the direct effects of macrophage subtypes on cartilage by culturing macrophage conditioned

  8. Activated microglia/macrophage whey acidic protein (AMWAP) inhibits NFκB signaling and induces a neuroprotective phenotype in microglia.

    Science.gov (United States)

    Aslanidis, Alexander; Karlstetter, Marcus; Scholz, Rebecca; Fauser, Sascha; Neumann, Harald; Fried, Cora; Pietsch, Markus; Langmann, Thomas

    2015-04-19

    Microglia reactivity is a hallmark of neurodegenerative diseases. We have previously identified activated microglia/macrophage whey acidic protein (AMWAP) as a counter-regulator of pro-inflammatory response. Here, we studied its mechanisms of action with a focus on toll-like receptor (TLR) and nuclear factor κB (NFκB) signaling. Recombinant AMWAP was produced in Escherichia coli and HEK293 EBNA cells and purified by affinity chromatography. AMWAP uptake was identified by fluorescent labeling, and pro-inflammatory microglia markers were measured by qRT-PCR after stimulation with TLR ligands. NFκB pathway proteins were assessed by immunocytochemistry, Western blot, and immunoprecipitation. A 20S proteasome activity assay was used to investigate the anti-peptidase activity of AMWAP. Microglial neurotoxicity was estimated by nitrite measurement and quantification of caspase 3/7 levels in 661W photoreceptors cultured in the presence of microglia-conditioned medium. Microglial proliferation was investigated using flow cytometry, and their phagocytosis was monitored by the uptake of 661W photoreceptor debris. AMWAP was secreted from lipopolysaccharide (LPS)-activated microglia and recombinant AMWAP reduced gene transcription of IL6, iNOS, CCL2, CASP11, and TNFα in BV-2 microglia treated with LPS as TLR4 ligand. This effect was replicated with murine embryonic stem cell-derived microglia (ESdM) and primary brain microglia. AMWAP also diminished pro-inflammatory markers in microglia activated with the TLR2 ligand zymosan but had no effects on IL6, iNOS, and CCL2 transcription in cells treated with CpG oligodeoxynucleotides as TLR9 ligand. Microglial uptake of AMWAP effectively inhibited TLR4-dependent NFκB activation by preventing IRAK-1 and IκBα proteolysis. No inhibition of IκBα phosphorylation or ubiquitination and no influence on overall 20S proteasome activity were observed. Functionally, both microglial nitric oxide (NO) secretion and 661W photoreceptor

  9. Red ginseng marc oil inhibits iNOS and COX-2 via NFκB and p38 pathways in LPS-stimulated RAW 264.7 macrophages.

    Science.gov (United States)

    Bak, Min-Ji; Hong, Soon-Gi; Lee, Jong-Won; Jeong, Woo-Sik

    2012-11-22

    In this study, we investigated the anti-inflammatory effects of red ginseng marc oil (RMO) in the RAW 264.7 macrophage cell line. RMO was prepared by a supercritical CO(2) extraction of waste product generated after hot water extraction of red ginseng. RMO significantly inhibited the production of oxidative stress molecules such as nitric oxide and reactive oxygen species in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Levels of inflammatory targets including prostaglandin E2, tumor necrosis factor-α, interleukin (IL)-1β and IL-6 were also reduced after the treatment with RMO. In addition, RMO diminished the expressions of inducible nitric oxide synthase and cyclooxygenase 2 at both mRNA and protein levels. Blockade of nuclear translocation of the p65 subunit of nuclear factor κB (NFκB) was also observed after the treatment of RMO. Furthermore, RMO decreased the phosphorylations of p38 mitogen-activated protein kinase (MAPK) and its upstream kinases including MAPK kinases 3/6 (MKK3/6) and TAK 1 (TGF-β activated kinase 1). Gas chromatographic analysis on RMO revealed that RMO contained about 10% phytosterols including sitosterol, stigmasterol and campesterol which may contribute to the anti-inflammatory properties of RMO. Taken together, these results suggest that the anti-inflammatory effect of RMO in LPS-induced RAW 264.7 macrophages could be associated with the inhibition of NFκB transcriptional activity, possibly via blocking the p38 MAPK pathway.

  10. THE MAPK ERK5, BUT NOT ERK1/2, INHIBITS THE PROGRESSION OF MONOCYTIC PHENOTYPE TO THE FUNCTIONING MACROPHAGE

    Science.gov (United States)

    Wang, Xuening; Pesakhov, Stella; Harrison, Jonathan S; Kafka, Michael; Danilenko, Michael; Studzinski, George P

    2014-01-01

    Intracellular signaling pathways present targets for pharmacological agents with potential for treatment of neoplastic diseases, with some disease remissions already recorded. However, cellular compensatory mechanisms usually negate the initial success. For instance, attempts to interrupt aberrant signaling downstream of the frequently mutated ras by inhibiting ERK1/2 has shown only limited usefulness for cancer therapy. Here, we examined how ERK5, that overlaps the functions of ERK1/2 in cell proliferation and survival, functions in a manner distinct from ERK1/2 in human AML cells induced to differentiate by 1,25D-dihydroxyvitamin D3 (1,25D). Using inhibitors of ERK1/2 and of MEK5/ERK5 at concentrations specific for each kinase in HL60 and U937 cells, we observed that selective inhibition of the kinase activity of ERK5, but not of ERK1/2, in the presence of 1,25D resulted in macrophage-like cell morphology and enhancement of phagocytic activity. Importantly, this was associated with increased expression of the macrophage colony stimulating factor receptor (M-CSFR), but was not seen when M-CSFR expression was knocked down. Interestingly, inhibition of ERK1/2 led to activation of ERK5 in these cells. Our results support the hypothesis that ERK5 negatively regulates the expression of M-CSFR, and thus has a restraining function on macrophage differentiation. The addition of pharmacological inhibitors of ERK5 may influence trials of differentiation therapy of AML. PMID:25447310

  11. Isocitrate dehydrogenase 1R132H mutation in microglia/macrophages in gliomas: Indication of a significant role of microglia/macrophages in glial tumorigenesis

    NARCIS (Netherlands)

    P.P. Zheng (Pingpin); M.M. van der Weiden (Marcel); P.J. van der Spek (Peter); A.J.P.E. Vincent (Arnoud); J.M. Kros (Johan)

    2012-01-01

    textabstractSomatic mutation of Isocitrate dehydrogenase 1 (IDH1) at the locus of R132 (IDH1R132H) occurs in > 70% of WHO grades II-III gliomas and secondary glioblastomas. To date it remains unknown whether the mutation is restricted to glial tumor cells. Microglial cells are the resident macrophag

  12. Erucin Exerts Anti-Inflammatory Properties in Murine Macrophages and Mouse Skin: Possible Mediation through the Inhibition of NFκB Signaling

    Directory of Open Access Journals (Sweden)

    Ki Won Lee

    2013-10-01

    Full Text Available Erucin, an isothiocyanate, is a hydrolysis product of glucoerucin found in arugula and has recently been reported to have anti-cancer properties in various cancer cells. In this study, we assessed the anti-inflammatory effects of erucin and the underlying mechanisms, using lipopolysaccharide (LPS-stimulated RAW 264.7 murine macrophages and 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin. In RAW 264.7 cells, erucin (2.5, 5 μmol/L inhibited LPS-induced production of nitric oxide and prostaglandin E2. Erucin inhibited LPS-induced degradation of the inhibitor of κBα and translocation of p65 to the nucleus and, subsequently, reduced LPS-induced nuclear factor κB (NFκB DNA binding activities, as well as the transcriptional activity of NFκB, leading to the decreased expression of NFκB-target genes, including tumor necrosis factor-α, interleukin (IL-6, IL-1β, inducible nitric oxide synthase (iNOS and cyclooxygenase (COX-2, as well as transcriptional activity of iNOS and COX-2. In mice, erucin (100, 300 nmoles treatment significantly inhibited phorbol ester-induced formation of ear edema and expression of iNOS and COX-2 proteins. These results indicate that erucin exerts a potent anti-inflammatory activity by inhibiting the pro-inflammatory enzymes and cytokines, which may be mediated, at least in part, via the inhibition of NFκB signaling.

  13. Erucin exerts anti-inflammatory properties in murine macrophages and mouse skin: possible mediation through the inhibition of NFκB signaling.

    Science.gov (United States)

    Cho, Han Jin; Lee, Ki Won; Park, Jung Han Yoon

    2013-10-15

    Erucin, an isothiocyanate, is a hydrolysis product of glucoerucin found in arugula and has recently been reported to have anti-cancer properties in various cancer cells. In this study, we assessed the anti-inflammatory effects of erucin and the underlying mechanisms, using lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages and 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin. In RAW 264.7 cells, erucin (2.5, 5 μmol/L) inhibited LPS-induced production of nitric oxide and prostaglandin E2. Erucin inhibited LPS-induced degradation of the inhibitor of κBα and translocation of p65 to the nucleus and, subsequently, reduced LPS-induced nuclear factor κB (NFκB) DNA binding activities, as well as the transcriptional activity of NFκB, leading to the decreased expression of NFκB-target genes, including tumor necrosis factor-α, interleukin (IL)-6, IL-1β, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, as well as transcriptional activity of iNOS and COX-2. In mice, erucin (100, 300 nmoles) treatment significantly inhibited phorbol ester-induced formation of ear edema and expression of iNOS and COX-2 proteins. These results indicate that erucin exerts a potent anti-inflammatory activity by inhibiting the pro-inflammatory enzymes and cytokines, which may be mediated, at least in part, via the inhibition of NFκB signaling.

  14. Using recombinant CD74 protein to inhibit the activity of macrophage migration inhibitory factor (MIF) in vitro

    Institute of Scientific and Technical Information of China (English)

    Zhi-xinSHAN; Xi-yongYU; Qiu-xiongLIN; Yong-hengFU

    2005-01-01

    AIM Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine involved in the pathogenesis of a variety of autoimmune and inflammatory diseases, including arthritis, glomerulonephritis, Gram-positive and Gram-negative sepsis, and atherogenesis. Recent studies showed that CD74(antigen-associated invariant chain Ⅱ) is a high-affinity membrane-binding protein for MIF. The purpose of the present study was to express the recombinant human CD74 in E. coli and inhibit the activity of MIF by using recombinant CD74 in vitro.

  15. Quercetin increases macrophage cholesterol efflux to inhibit foam cell formation through activating PPARγ-ABCA1 pathway

    Science.gov (United States)

    Sun, Liqiang; Li, En; Wang, Feng; Wang, Tao; Qin, Zhiping; Niu, Shaohui; Qiu, Chunguang

    2015-01-01

    The accumulation of cholesterol in macrophages could induce the formation of foam cells and increase the risk of developing atherosclerosis. We wonder if quercetin, one of flavonoids with anti-inflammation functions in different cell types, could elevate the development of foam cells formation in atherosclerosis. We treated foam cells derived from oxLDL induced THP-1 cells with quercetin, and evaluated the foam cells formation, cholesterol content and apoptosis of the cells. We found that quercetin induced the expression of ABCA1 in differentiated THP-1 cells, and increased the cholesterol efflux from THP-1 cell derived foam cells. Eventually, cholesterol level and the formation of foam cell derived from THP-1 cells decreased after quercetin treatment. In addition, quercetin activated PPARγ-LXRα pathway to upregulate ABCA1 expression through increasing protein level of PPARγ and its transcriptional activity. Inhibition of PPARγ activity by siRNA knockdown or the addition of chemical inhibitor, GW9662, abolished quercetin induced ABCA1 expression and cholesterol efflux in THP-1 derived macrophages. Our data demonstrated that quercetin increased cholesterol efflux from macrophages through upregulating the expressions of PPARγ and ABCA1. Taken together, increasing uptake of quercetin or quercetin-rich foods would be an effective way to lower the risk of atherosclerosis. PMID:26617799

  16. Naringin lauroyl ester inhibits lipopolysaccharide-induced activation of nuclear factor κB signaling in macrophages.

    Science.gov (United States)

    Hattori, Hiromi; Tsutsuki, Hiroyasu; Nakazawa, Masami; Ueda, Mitsuhiro; Ihara, Hideshi; Sakamoto, Tatsuji

    2016-07-01

    Naringin (Nar) has antioxidant and anti-inflammatory properties. It was recently reported that enzymatic modification of Nar enhanced its functions. Here, we acylated Nar with fatty acids of different sizes (C2-C18) using immobilized lipase from Rhizomucor miehei and investigated the anti-inflammatory effects of these molecules. Treatment of murine macrophage RAW264.7 cells with Nar alkyl esters inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production, with Nar lauroyl ester (Nar-C12) showing the strongest effect. Furthermore, Nar-C12 suppressed the LPS-induced expression of inducible NO synthase by blocking the phosphorylation of inhibitor of nuclear factor (NF)-κB-α as well as the nuclear translocation of NF-κB subunit p65 in macrophage cells. Analysis of Nar-C12 uptake in macrophage cells revealed that Nar-C12 ester bond was partially degraded in the cell membrane and free Nar was translocated to the cytosol. These results indicate that Nar released from Nar-C12 exerts anti-inflammatory effects by suppressing NF-κB signaling pathway.

  17. Inhibition of Emodin on LPS-induced Nitric Oxide Generation by Suppressing PLC-γ Phosphorylation in Rat Peritoneal Macrophages

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-yu; CAI Shou-guang; WU Yi-fen; LI Jun-ying; YANG Wen-xiu; HU Fen

    2010-01-01

    Objective To investigate the inhibitory mechanism of emodin on lipopolysaccharide(LPS)-induced nitric oxide(NO)generation in rat peritoneal macrophages.Methods NO production and iNOS expression were measured through nitrite assay and Western blotting assay,respectively.NF-kB activity and nuclei P65 expression were estimated by dual-luciferase and Western blotting assay,respectively.Intracellular free Ca2+([Ca2+]i)was detected using the ratiometric fluorescent calcium indicator dye,Fura-2,and a microspectrofluorometer.PLC-γphosporylation was analyzed by Western blotting assay.Results First,emodin was found playing active roles in suppressing LPS-induced NF-kB activation in rat peritoneal macrophages.Second,emodin down-regulated transient[Ca2*]i and could increase in NF-kB upstream signal.Finally,emodin suppressed phosphorylation of PLC-γ by LPS stimulation in the upstream of[Ca2+]i.Conclusion Suppression of PLC-γ phosphorylation is involved in emodin inhibiting NO generation by LPS stimulation in rat peritoneal macrophages.

  18. Roxatidine suppresses inflammatory responses via inhibition of NF-κB and p38 MAPK activation in LPS-induced RAW 264.7 macrophages.

    Science.gov (United States)

    Cho, Eu-Jin; An, Hyo-Jin; Shin, Ji-Sun; Choi, Hye-Eun; Ko, Jane; Cho, Young-Wuk; Kim, Hyung-Min; Choi, Jung-Hye; Lee, Kyung-Tae

    2011-12-01

    Roxatidine is a novel, specific, competitive H(2) -receptor antagonist that is used to treat gastric and duodenal ulcers, and which is known to suppress the growth of several tumors by reducing vascular endothelial growth factor (VEGF) expression. Nevertheless, it remains unclear whether roxatidine has anti-inflammatory effects. In this study, we the authors investigated the anti-inflammatory effect of roxatidine in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. It was found that roxatidine dose-dependently inhibited the productions of prostaglandin E(2) (PGE(2)), nitric oxide (NO), and histamine, and the protein and mRNA expressions of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and histidine decarboxylase (HDC). In addition, roxatidine reduced the productions and expressions of VEGF-1 and pro-inflammatory cytokines, including those of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). Electrophoretic mobility shift assays (EMSA) and reporter gene assays revealed that treatment with roxatidine attenuated the LPS-induced DNA-binding and transcriptional activity of nuclear factor kappa B (NF-κB). In addition, it was found that pretreatment with roxatidine significantly inhibited the nuclear translocations of the p65 and p50 subunits of NF-κB, and these inhibitions were not found to be associated with decreases in the phosphorylation or degradation of inhibitory kappa B-α (IκBα). Furthermore, roxatidine suppressed the phosphorylation of p38 MAP kinase, but not of IκB kinase-α/β (IKKα/β), c-Jun NH(2) -terminal kinase (JNK), or extracellular signal-regulated kinase (ERK). Taken together, these results indicate that the anti-inflammatory properties of roxatidine in LPS-treated RAW 264.7 macrophages are mediated by the inhibition of NF-κB transcriptional activity and the p38 MAP kinase pathway.

  19. Endogenous levels of Echinacea alkylamides and ketones are important contributors to the inhibition of prostaglandin E2 and nitric oxide production in cultured macrophages

    Science.gov (United States)

    LaLone, Carlie A.; Rizshsky, Ludmila; Hammer, Kimberly D.P.; Wu, Lankun; Solco, Avery K.S.; Yum, Manyu; Nikolau, Basil J.; Wurtele, Eve S.; Murphy, Patricia A.; Kim, Meehye; Birt, Diane F.

    2009-01-01

    Due to the popularity of Echinacea as a dietary supplement, researchers have been actively investigating which Echinacea constituent or groups of constituents are necessary for immune modulating bioactivities. Our prior studies indicate that alkylamides may play an important role in the inhibition of prostaglandin E2 (PGE2) production. HPLC fractionation, employed to elucidate interacting anti-inflammatory constituents from ethanol extracts of E. purpurea, E. angustifolia, E. pallida, and E. tennesseensis identified fractions containing alkylamides and ketones as key anti-inflammatory contributors using lipopolysaccharide induced PGE2 production in RAW264.7 mouse macrophage cells. Nitric oxide (NO) production and parallel cytotoxicity screens were also employed to substantiate an anti-inflammatory response. Echinacea pallida showed significant inhibition of PGE2 with a first round fraction, containing GC-MS peaks for Bauer Ketones 20, 21, 22, 23, and 24, with 23 and 24 identified as significant contributors to this PGE2 inhibition. Chemically synthesized Bauer Ketones 21 and 23 at 1 μM each significantly inhibited both PGE2 and NO production. Three rounds of fractionation were produced from an E. angustifolia extract. GC-MS analysis identified the presence of Bauer Ketone 23 in third round Fraction 3D32 and Bauer Alkylamide 11 making up 96% of third round Fraction 3E40. Synthetic Bauer Ketone 23 inhibited PGE2 production to 83 % of control and synthetic Bauer Alkylamide 11 significantly inhibited PGE2 and NO production at the endogenous concentrations determined to be present in their respective fraction, thus each constituent partially explained the in vitro anti-inflammatory activity of their respective fraction. From this study two key contributors to the anti-inflammatory properties of E. angustifolia were identified as Bauer Alkylamide 11 and Bauer Ketone 23. PMID:19807154

  20. Estrogen-induced nongenomic calcium signaling inhibits lipopolysaccharide-stimulated tumor necrosis factor α production in macrophages.

    Directory of Open Access Journals (Sweden)

    Limin Liu

    Full Text Available Estrogen is traditionally thought to exert genomic actions through members of the nuclear receptor family. Here, we investigated the rapid nongenomic effects of 17β-estradiol (E2 on tumor necrosis factor α (TNF-α production following lipopolysaccharide (LPS stimulation in mouse bone marrow-derived macrophages (BMMs. We found that LPS induced TNF-α production in BMMs via phosphorylation of p38 mitogen-activated protein kinase (MAPK. E2 itself did not affect the MAPK pathway, although it attenuated LPS-induced TNF-α production through suppression of p38 MAPK activation. Recently, G protein-coupled receptor 30 (GPR30 was suggested to be a membrane estrogen receptor (mER that can mediate nongenomic estradiol signaling. We found that BMMs expressed both intracellular estrogen receptors (iER and mER GPR30. The specific GPR30 antagonist G-15 significantly blocked effects of estradiol on LPS-induced TNF-α production, whereas an iER antagonist did not. Moreover, E2 induced a rapid rise in intracellular free Ca(2+ that was due to the influx of extracellular Ca(2+ and was not inhibited by an iER antagonist or silencing of iER. Ca(2+ influx was also induced by an impermeable E2 conjugated to BSA (E2-BSA, which has been used to investigate the nongenomic effects of estrogen. Consequently, Ca(2+, a pivotal factor in E2-stimulated nongenomic action, was identified as the key mediator. The inhibitory effects of E2 on LPS-induced TNF-α production and p38 MAPK phosphorylation were dependent on E2-triggered Ca(2+ influx because BAPTA, an intracellular Ca(2+ chelator, prevented these effects. Taken together, these data indicate that E2 can down-regulate LPS-induced TNF-α production via blockade of p38 MAPK phosphorylation through the mER-mediated nongenomic Ca(2+ signaling pathway in BMMs.

  1. Riboflavin deprivation inhibits macrophage viability and activity - a study on the RAW 264.7 cell line.

    Science.gov (United States)

    Mazur-Bialy, Agnieszka Irena; Buchala, Beata; Plytycz, Barbara

    2013-08-28

    Riboflavin, or vitamin B2, as a precursor of the coenzymes FAD and FMN, has an indirect influence on many metabolic processes and determines the proper functioning of several systems, including the immune system. In the human population, plasma riboflavin concentration varies from 3·1 nM (in a moderate deficiency, e.g. in pregnant women) to 10·4 nM (in healthy adults) and 300 nM (in cases of riboflavin supplementation). The purpose of the present study was to investigate the effects of riboflavin concentration on the activity and viability of macrophages, i.e. on one of the immunocompetent cell populations. The study was performed on the murine monocyte/macrophage RAW 264.7 cell line cultured in medium with various riboflavin concentrations (3·1, 10·4, 300 and 531 nM). The results show that riboflavin deprivation has negative effects on both the activity and viability of macrophages and reduces their ability to generate an immune response. Signs of riboflavin deficiency developed in RAW 264.7 cells within 4 d of culture in the medium with a low riboflavin concentration (3·1 nM). In particular, the low riboflavin content reduced the proliferation rate and enhanced apoptotic cell death connected with the release of lactate dehydrogenase. The riboflavin deprivation impaired cell adhesion, completely inhibited the respiratory burst and slightly impaired phagocytosis of the zymosan particles. In conclusion, macrophages are sensitive to riboflavin deficiency; thus, a low riboflavin intake in the diet may affect the immune system and may consequently decrease proper host immune defence.

  2. PGE2-treated macrophages inhibit development of allergic lung inflammation in mice

    NARCIS (Netherlands)

    Draijer, Christina; Boorsma, Carian E; Reker-Smit, Catharina; Post, Eduard; Poelstra, Klaas; Melgert, Barbro N

    2016-01-01

    In healthy lungs, many macrophages are characterized by IL-10 production, and few are characterized by expression of IFN regulatory factor 5 (formerly M1) or YM1 and/or CD206 (formerly M2), whereas in asthma, this balance shifts toward few producing IL-10 and many expressing IFN regulatory factor 5

  3. Blueberries inhibit proinflammatory cytokine TNF-alpha and IL-6 production in macrophages

    Science.gov (United States)

    Blueberries (BB) have been reported to attenuate atherosclerosis in apoE deficient (ApoE-/-) mice. However, the underlying mechanisms are not fully understood. In this study, the effect of BB on proinflammatory cytokine production in macrophages was investigated. ApoE-/- mice were fed AIN-93G diet (...

  4. Interaction of the European genotype porcine reproductive and respiratory syndrome virus (PRRSV with sialoadhesin (CD169/Siglec-1 inhibits alveolar macrophage phagocytosis

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    De Baere Miet I

    2012-05-01

    Full Text Available Abstract Porcine reproductive and respiratory syndrome virus (PRRSV is an arterivirus that shows a restricted in vivo tropism for subsets of porcine macrophages, with alveolar macrophages being major target cells. The virus is associated with respiratory problems in pigs of all ages and is commonly isolated on farms with porcine respiratory disease complex (PRDC. Due to virus-induced macrophage death early in infection, PRRSV hampers the innate defence against pathogens in the lungs. In addition, the virus might also directly affect the antimicrobial functions of macrophages. This study examined whether interaction of European genotype PRRSV with primary alveolar macrophages (PAM affects their phagocytic capacity. Inoculation of macrophages with both subtype I PRRSV (LV and subtype III PRRSV (Lena showed that the virus inhibits PAM phagocytosis. Similar results were obtained using inactivated PRRSV (LV, showing that initial interaction of the virion with the cell is sufficient to reduce phagocytosis, and that no productive infection is required. When macrophages were incubated with sialoadhesin- (Sn or CD163-specific antibodies, two entry mediators of the virus, only Sn-specific antibodies downregulated the phagocytic capacity of PAM, indicating that interaction with Sn, but not CD163, mediates the inhibitory effect of PRRSV on phagocytosis. In conclusion, this study shows that European genotype PRRSV inhibits PAM phagocytosis in vitro, through the interaction with its internalization receptor Sn. If similar events occur in vivo, this interaction may be important in the development of PRDC, as often seen in the field.

  5. β-arrestin2 in infiltrated macrophages inhibits excessive inflammation after myocardial infarction.

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    Kenji Watari

    Full Text Available Beta-arrestins (β-arrestin1 and β-arrestin2 are known as cytosolic proteins that mediate desensitization and internalization of activated G protein-coupled receptors. In addition to these functions, β-arrestins have been found to work as adaptor proteins for intracellular signaling pathways. β-arrestin1 and β-arrestin2 are expressed in the heart and are reported to participate in normal cardiac function. However, the physiological and pathological roles of β-arrestin1/2 in myocardial infarction (MI have not been examined. Here, we demonstrate that β-arrestin2 negatively regulates inflammatory responses of macrophages recruited to the infarct area. β-arrestin2 knockout (KO mice have higher mortality than wild-type (WT mice after MI. In infarcted hearts, β-arrestin2 was strongly expressed in infiltrated macrophages. The production of inflammatory cytokines was enhanced in β-arrestin2 KO mice. In addition, p65 phosphorylation in the macrophages from the infarcted hearts of β-arrestin2 KO mice was increased in comparison to that of WT mice. These results suggest that the infiltrated macrophages of β-arrestin2 KO mice induce excessive inflammation at the infarct area. Furthermore, the inflammation in WT mice transplanted with bone marrow cells of β-arrestin2 KO mice is enhanced by MI, which is similar to that in β-arrestin2 KO mice. In contrast, the inflammation after MI in β-arrestin2 KO mice transplanted with bone marrow cells of WT mice is comparable to that in WT mice transplanted with bone marrow cells of WT mice. In summary, our present study demonstrates that β-arrestin2 of infiltrated macrophages negatively regulates inflammation in infarcted hearts, thereby enhancing inflammation when the β-arrestin2 gene is knocked out. β-arrestin2 plays a protective role in MI-induced inflammation.

  6. β-arrestin2 in infiltrated macrophages inhibits excessive inflammation after myocardial infarction.

    Science.gov (United States)

    Watari, Kenji; Nakaya, Michio; Nishida, Motohiro; Kim, Kyeong-Man; Kurose, Hitoshi

    2013-01-01

    Beta-arrestins (β-arrestin1 and β-arrestin2) are known as cytosolic proteins that mediate desensitization and internalization of activated G protein-coupled receptors. In addition to these functions, β-arrestins have been found to work as adaptor proteins for intracellular signaling pathways. β-arrestin1 and β-arrestin2 are expressed in the heart and are reported to participate in normal cardiac function. However, the physiological and pathological roles of β-arrestin1/2 in myocardial infarction (MI) have not been examined. Here, we demonstrate that β-arrestin2 negatively regulates inflammatory responses of macrophages recruited to the infarct area. β-arrestin2 knockout (KO) mice have higher mortality than wild-type (WT) mice after MI. In infarcted hearts, β-arrestin2 was strongly expressed in infiltrated macrophages. The production of inflammatory cytokines was enhanced in β-arrestin2 KO mice. In addition, p65 phosphorylation in the macrophages from the infarcted hearts of β-arrestin2 KO mice was increased in comparison to that of WT mice. These results suggest that the infiltrated macrophages of β-arrestin2 KO mice induce excessive inflammation at the infarct area. Furthermore, the inflammation in WT mice transplanted with bone marrow cells of β-arrestin2 KO mice is enhanced by MI, which is similar to that in β-arrestin2 KO mice. In contrast, the inflammation after MI in β-arrestin2 KO mice transplanted with bone marrow cells of WT mice is comparable to that in WT mice transplanted with bone marrow cells of WT mice. In summary, our present study demonstrates that β-arrestin2 of infiltrated macrophages negatively regulates inflammation in infarcted hearts, thereby enhancing inflammation when the β-arrestin2 gene is knocked out. β-arrestin2 plays a protective role in MI-induced inflammation.

  7. Nur77 inhibits oxLDL induced apoptosis of macrophages via the p38 MAPK signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Qin; Han, Fei; Peng, Shi; He, Ben, E-mail: heben@medmail.com.cn

    2016-03-18

    The interaction between macrophages and oxLDL plays a crucial role in the initiation and progression of atherosclerosis. As a key initiator in a number of plaque promoting processes, oxLDL induces variable effects such as cell apoptosis or proliferation. Orphan nuclear receptor Nur77 is potently induced in macrophages by diverse stimuli, suggesting that it is of importance in vascular inflammation resulting in atherosclerosis, but whether Nur77 induction is detrimental or protective is unclear. In our study, we explore the role of Nur77 in the regulation of oxLDL-induced macrophage apoptosis and the signaling pathways that are involved. We found that oxLDL induced Nur77 expression in a dose and time dependent fashion, and cell viability was decreased in parallel. To determine whether Nur77 induction contributes to the loss of cell viability or is a protective mechanism, the effect of Nur77 overexpression was examined. Importantly, Nur77 overexpression inhibited the oxLDL-induced decrease of cell viability, inhibited the production of apoptotic bodies and restored DNA synthesis following oxLDL exposure. Furthermore, we found that Nur77 induction is mediated through the p38 MAPK signaling pathway. After pretreatment with SB203580, cell viability was decreased, the expression of CyclinA2 and PCNA was attenuated and the percentage of cell apoptosis was enhanced. Likewise, Nur77 overexpression increased the expression of the cell cycle genes PCNA and p21, and attenuated the increase in caspase-3. On the other hand, knockdown of Nur77 expression by specific siRNA resulted in the increased expression of caspase 3. The results demonstrate that Nur77 is induced by oxLDL via the p38 MAPK signaling pathway, which is involved in the regulation of cell survival. Nur77 enhanced cell survival via suppressing apoptosis, without affecting cell proliferation of activated macrophages, which may be beneficial in patients with atherosclerosis. - Highlights: • oxLDL could induce Nur77

  8. Glibenclamide decreases ATP-induced intracellular calcium transient elevation via inhibiting reactive oxygen species and mitochondrial activity in macrophages.

    Directory of Open Access Journals (Sweden)

    Duo-ling Li

    Full Text Available Increasing evidence has revealed that glibenclamide has a wide range of anti-inflammatory effects. However, it is unclear whether glibenclamide can affect the resting and adenosine triphosphate (ATP-induced intracellular calcium ([Ca(2+]i handling in Raw 264.7 macrophages. In the present study, [Ca(2+]i transient, reactive oxygen species (ROS and mitochondrial activity were measured by the high-speed TILLvisION digital imaging system using the indicators of Fura 2-am, DCFDA and rhodamine-123, respectively. We found that glibenclamide, pinacidil and other unselective K(+ channel blockers had no effect on the resting [Ca(2+]i of Raw 264.7 cells. Extracellular ATP (100 µM induced [Ca(2+]i transient elevation independent of extracellular Ca(2+. The transient elevation was inhibited by an ROS scavenger (tiron and mitochondria inhibitor (rotenone. Glibenclamide and 5-hydroxydecanoate (5-HD also decreased ATP-induced [Ca(2+]i transient elevation, but pinacidil and other unselective K(+ channel blockers had no effect. Glibenclamide also decreased the peak of [Ca(2+]i transient induced by extracellular thapsigargin (Tg, 1 µM. Furthermore, glibenclamide decreased intracellular ROS and mitochondrial activity. When pretreated with tiron and rotenone, glibenclamide could not decrease ATP, and Tg induced maximal [Ca(2+]i transient further. We conclude that glibenclamide may inhibit ATP-induced [Ca(2+]i transient elevation by blocking mitochondria KATP channels, resulting in decreased ROS generation and mitochondrial activity in Raw 264.7 macrophages.

  9. Omega-3 free fatty acids suppress macrophage inflammasome activation by inhibiting NF-κB activation and enhancing autophagy.

    Directory of Open Access Journals (Sweden)

    Yolanda Williams-Bey

    Full Text Available The omega-3 (ω3 fatty acid docosahexaenoic acid (DHA can suppress inflammation, specifically IL-1β production through poorly understood molecular mechanisms. Here, we show that DHA reduces macrophage IL-1β production by limiting inflammasome activation. Exposure to DHA reduced IL-1β production by ligands that stimulate the NLRP3, AIM2, and NAIP5/NLRC4 inflammasomes. The inhibition required Free Fatty Acid Receptor (FFAR 4 (also known as GPR120, a G-protein coupled receptor (GPR known to bind DHA. The exposure of cells to DHA recruited the adapter protein β-arrestin1/2 to FFAR4, but not to a related lipid receptor. DHA treatment reduced the initial inflammasome priming step by suppressing the nuclear translocation of NF-κB. DHA also reduced IL-1β levels by enhancing autophagy in the cells. As a consequence macrophages derived from mice lacking the essential autophagy protein ATG7 were partially resistant to suppressive effects of DHA. Thus, DHA suppresses inflammasome activation by two distinct mechanisms, inhibiting the initial priming step and by augmenting autophagy, which limits inflammasome activity.

  10. Vitamin D inhibits human immunodeficiency virus type 1 and Mycobacterium tuberculosis infection in macrophages through the induction of autophagy.

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    Grant R Campbell

    Full Text Available Low vitamin D levels in human immunodeficiency virus type-1 (HIV infected persons are associated with more rapid disease progression and increased risk for Mycobacterium tuberculosis infection. We have previously shown that 1α,25-dihydroxycholecalciferol (1,25D3, the active form of vitamin D, inhibits HIV replication in human macrophages through the induction of autophagy. In this study, we report that physiological concentrations of 1,25D3 induce the production of the human cathelicidin microbial peptide (CAMP and autophagic flux in HIV and M. tuberculosis co-infected human macrophages which inhibits mycobacterial growth and the replication of HIV. Using RNA interference for Beclin-1 and the autophagy-related 5 homologue, combined with the chemical inhibitors of autophagic flux, bafilomycin A₁, an inhibitor of autophagosome-lysosome fusion and subsequent acidification, and SID 26681509 an inhibitor of the lysosome hydrolase cathepsin L, we show that the 1,25D3-mediated inhibition of HIV replication and mycobacterial growth during single infection or dual infection is dependent not only upon the induction of autophagy, but also through phagosomal maturation. Moreover, through the use of RNA interference for CAMP, we demonstrate that cathelicidin is essential for the 1,25D3 induced autophagic flux and inhibition of HIV replication and mycobacterial growth. The present findings provide a biological explanation for the benefits and importance of vitamin D sufficiency in HIV and M. tuberculosis-infected persons, and provide new insights into novel approaches to prevent and treat HIV infection and related opportunistic infections.

  11. In-vitro anti-inflammatory effect of Eucalyptus globulus and Thymus vulgaris: nitric oxide inhibition in J774A.1 murine macrophages.

    Science.gov (United States)

    Vigo, E; Cepeda, A; Gualillo, O; Perez-Fernandez, R

    2004-02-01

    It is well known that nitric oxide (NO) plays an important role in the pathogenesis of inflammatory diseases. Eucalyptus globulus Labill. and Thymus vulgaris L. have been used in traditional medicine in the treatment of bronchitis, asthma and other respiratory diseases. The present study focuses on the effects of these two extracts on NO production induced by lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) in the murine macrophage cell line J774A.1. In addition, cell viability, scavenging activity and inducible nitric oxide synthase (iNOS) mRNA expression were evaluated. E. globulus and T. vulgaris extracts significantly inhibited the enhanced production of NO induced by LPS and IFN-gamma in a dose-dependent manner. Treatment with these two extracts did not reduce cell viability at any dose used. Both plant extracts showed significant scavenging of NO radicals released by an NO donor, PAPA-NONOate. Results also show that pre-treatment with E. globulus and T. vulgaris extracts significantly inhibits iNOS mRNA expression. This study thus suggests that the inhibition of net NO production by these two extracts may be due to their NO scavenging activity and/or their inhibitory effects on iNOS gene expression.

  12. A novel compound DSC suppresses lipopolysaccharide-induced inflammatory responses by inhibition of Akt/NF-κB signalling in macrophages.

    Science.gov (United States)

    Liu, Xin-Hua; Pan, Li-Long; Jia, Yao-Ling; Wu, Dan; Xiong, Qing-Hui; Wang, Yang; Zhu, Yi-Zhun

    2013-05-15

    A novel compound [4-(2-acetoxy-3-((R)-3-(benzylthio)-1-methoxy-1-oxopropan-2-ylamino)-3-oxopropyl)-1,2-phenylene diacetate (DSC)], derived from Danshensu, exerted cytoprotective effects by anti-oxidative and anti-apoptotic activities in vitro. Herein, we reported the protective effects of DSC on lipopolysaccharide (LPS)-induced inflammatory responses in murine RAW264.7 macrophages and the underlying mechanisms. We showed that DSC concentration-dependently attenuated nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression with less cytotoxicity. Signal transduction studies indicated that DSC significantly inhibited LPS-induced phosphorylation of Akt, but not c-Jun N-terminal kinase 1/2, p38, or extracellular signal-regulated kinase 1/2. Meanwhile, LPS-induced nuclear translocation of nuclear factor-κB (NF-κB) p65 was decreased by DSC. Furthermore, a phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 significantly suppressed LPS-induced NF-κB p65 nuclear translocation, iNOS expression, and NO production, which was also mimicked by pretreatment with DSC. These results suggested that DSC attenuated LPS-induced inflammatory response in macrophages, at least in part, through suppression of PI3K/Akt signaling and NF-κB activation.

  13. 15-Deoxy-Δ12,14-prostaglandin J2 inhibits macrophage colonization by Salmonella enterica serovar Typhimurium.

    Science.gov (United States)

    Buckner, Michelle M C; Antunes, L Caetano M; Gill, Navkiran; Russell, Shannon L; Shames, Stephanie R; Finlay, B Brett

    2013-01-01

    15-deoxy-Δ(12,14)-prostaglandin J2 (15d-PGJ2) is an anti-inflammatory downstream product of the cyclooxygenase enzymes. It has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. Here we show that 15d-PGJ2 also plays a role in Salmonella infection. Salmonella enterica Typhimurium is a Gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocytic immune cells, allowing for bacterial dissemination to systemic sites. Salmonella species cause a wide range of morbidity and mortality due to gastroenteritis and typhoid fever. Previously we have shown that in mouse models of typhoid fever, Salmonella infection causes a major perturbation in the prostaglandin pathway. Specifically, we saw that 15d-PGJ2 production was significantly increased in both liver and feces. In this work we show that 15d-PGJ2 production is also significantly increased in macrophages infected with Salmonella. Furthermore, we show that the addition of 15d-PGJ2 to Salmonella infected RAW264.7, J774, and bone marrow derived macrophages is sufficient to significantly reduce bacterial colonization. We also show evidence that 15d-PGJ2 is reducing bacterial uptake by macrophages. 15d-PGJ2 reduces the inflammatory response of these infected macrophages, as evidenced by a reduction in the production of cytokines and reactive nitrogen species. The inflammatory response of the macrophage is important for full Salmonella virulence, as it can give the bacteria cues for virulence. The reduction in bacterial colonization is independent of the expression of Salmonella virulence genes SPI1 and SPI2, and is independent of the 15d-PGJ2 ligand PPAR-γ. 15d-PGJ2 also causes an increase in ERK1/2 phosphorylation in infected macrophages. In conclusion, we show here that 15d-PGJ2 mediates the outcome of bacterial infection, a previously unidentified role for this

  14. 15-Deoxy-Δ12,14-prostaglandin J2 inhibits macrophage colonization by Salmonella enterica serovar Typhimurium.

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    Michelle M C Buckner

    Full Text Available 15-deoxy-Δ(12,14-prostaglandin J2 (15d-PGJ2 is an anti-inflammatory downstream product of the cyclooxygenase enzymes. It has been implicated to play a protective role in a variety of inflammatory mediated diseases, including rheumatoid arthritis, neural damage, and myocardial infarctions. Here we show that 15d-PGJ2 also plays a role in Salmonella infection. Salmonella enterica Typhimurium is a Gram-negative facultative intracellular pathogen that is able to survive and replicate inside phagocytic immune cells, allowing for bacterial dissemination to systemic sites. Salmonella species cause a wide range of morbidity and mortality due to gastroenteritis and typhoid fever. Previously we have shown that in mouse models of typhoid fever, Salmonella infection causes a major perturbation in the prostaglandin pathway. Specifically, we saw that 15d-PGJ2 production was significantly increased in both liver and feces. In this work we show that 15d-PGJ2 production is also significantly increased in macrophages infected with Salmonella. Furthermore, we show that the addition of 15d-PGJ2 to Salmonella infected RAW264.7, J774, and bone marrow derived macrophages is sufficient to significantly reduce bacterial colonization. We also show evidence that 15d-PGJ2 is reducing bacterial uptake by macrophages. 15d-PGJ2 reduces the inflammatory response of these infected macrophages, as evidenced by a reduction in the production of cytokines and reactive nitrogen species. The inflammatory response of the macrophage is important for full Salmonella virulence, as it can give the bacteria cues for virulence. The reduction in bacterial colonization is independent of the expression of Salmonella virulence genes SPI1 and SPI2, and is independent of the 15d-PGJ2 ligand PPAR-γ. 15d-PGJ2 also causes an increase in ERK1/2 phosphorylation in infected macrophages. In conclusion, we show here that 15d-PGJ2 mediates the outcome of bacterial infection, a previously unidentified

  15. Molecular Consequences of Proprotein Convertase 1/3 (PC1/3) Inhibition in Macrophages for Application to Cancer Immunotherapy: A Proteomic Study*

    Science.gov (United States)

    Duhamel, Marie; Rodet, Franck; Delhem, Nadira; Vanden Abeele, Fabien; Kobeissy, Firas; Nataf, Serge; Pays, Laurent; Desjardins, Roxanne; Gagnon, Hugo; Wisztorski, Maxence; Fournier, Isabelle; Day, Robert; Salzet, Michel

    2015-01-01

    Macrophages provide the first line of host immune defense. Their activation triggers the secretion of pro-inflammatory cytokines and chemokines recruiting other immune cells. In cancer, macrophages present an M2 anti-inflammatory phenotype promoting tumor growth. In this way, strategies need to be develop to reactivate macrophages. Previously thought to be expressed only in cells with a neural/neuroendocrine phenotype, the proprotein convertase 1/3 has been shown to also be expressed in macrophages and regulated as a function of the Toll-like receptor immune response. Here, we investigated the intracellular impact of the down-regulation of the proprotein convertase 1/3 in NR8383 macrophages and confirmed the results on macrophages from PC1/3 deficient mice. A complete proteomic study of secretomes and intracellular proteins was undertaken and revealed that inhibition of proprotein convertase 1/3 orient macrophages toward an M1 activated phenotype. This phenotype is characterized by filopodial extensions, Toll-like receptor 4 MyD88-dependent signaling, calcium entry augmentation and the secretion of pro-inflammatory factors. In response to endotoxin/lipopolysaccharide, these intracellular modifications increased, and the secreted factors attracted naïve T helper lymphocytes to promote the cytotoxic response. Importantly, the application of these factors onto breast and ovarian cancer cells resulted in a decrease viability or resistance. Under inhibitory conditions using interleukin 10, PC1/3-knockdown macrophages continued to secrete inflammatory factors. These data indicate that targeted inhibition of proprotein convertase 1/3 could represent a novel type of immune therapy to reactivate intra-tumoral macrophages. PMID:26330543

  16. A pseudopterane diterpene isolated from the octocoral Pseudopterogorgia acerosa inhibits the inflammatory response mediated by TLR-ligands and TNF-alpha in macrophages.

    Science.gov (United States)

    González, Yisett; Doens, Deborah; Santamaría, Ricardo; Ramos, Marla; Restrepo, Carlos M; Barros de Arruda, Luciana; Lleonart, Ricardo; Gutiérrez, Marcelino; Fernández, Patricia L

    2013-01-01

    Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1) isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α) and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), interferon gamma-induced protein 10 (IP-10), ciclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1) induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation.

  17. A pseudopterane diterpene isolated from the octocoral Pseudopterogorgia acerosa inhibits the inflammatory response mediated by TLR-ligands and TNF-alpha in macrophages.

    Directory of Open Access Journals (Sweden)

    Yisett González

    Full Text Available Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1 isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL-6, IL-1β, nitric oxide (NO, interferon gamma-induced protein 10 (IP-10, ciclooxygenase (COX-2, inducible nitric oxide synthase (iNOS and monocyte chemoattractant protein-1 (MCP-1 induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation.

  18. A Pseudopterane Diterpene Isolated From the Octocoral Pseudopterogorgia acerosa Inhibits the Inflammatory Response Mediated by TLR-Ligands and TNF-Alpha in Macrophages

    Science.gov (United States)

    González, Yisett; Doens, Deborah; Santamaría, Ricardo; Ramos, Marla; Restrepo, Carlos M.; Barros de Arruda, Luciana; Lleonart, Ricardo; Gutiérrez, Marcelino; Fernández, Patricia L.

    2013-01-01

    Several diterpenoids isolated from terrestrial and marine environments have been identified as important anti-inflammatory agents. Although considerable progress has been made in the area of anti-inflammatory treatment, the search for more effective and safer compounds is a very active field of research. In this study we investigated the anti-inflammatory effects of a known pseudopterane diterpene (referred here as compound 1) isolated from the octocoral Pseudopterogorgia acerosa on the tumor necrosis factor- alpha (TNF-α) and TLRs- induced response in macrophages. Compound 1 inhibited the expression and secretion of the inflammatory mediators TNF-α, interleukin (IL)-6, IL-1β, nitric oxide (NO), interferon gamma-induced protein 10 (IP-10), ciclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and monocyte chemoattractant protein-1 (MCP-1) induced by LPS in primary murine macrophages. This effect was associated with the inhibition of IκBα degradation and subsequent activation of NFκB. Compound 1 also inhibited the expression of the co-stimulatory molecules CD80 and CD86, which is a hallmark of macrophage activation and consequent initiation of an adaptive immune response. The anti-inflammatory effect was not exclusive to LPS because compound 1 also inhibited the response of macrophages to TNF-α and TLR2 and TLR3 ligands. Taken together, these results indicate that compound 1 is an anti-inflammatory molecule, which modulates a variety of processes occurring in macrophage activation. PMID:24358331

  19. Sustained Small Interfering RNA-Mediated Human Immunodeficiency Virus Type 1 Inhibition in Primary Macrophages

    OpenAIRE

    2003-01-01

    Small interfering RNAs (siRNAs) can induce potent gene silencing by degradation of cognate mRNA. However, in dividing cells, the silencing lasts only 3 to 7 days, presumably because of siRNA dilution with cell division. Here, we investigated if sustained siRNA-mediated silencing of human immunodeficiency virus type 1 (HIV-1) is possible in terminally differentiated macrophages, which constitute an important reservoir of HIV in vivo. CCR5, the major HIV-1 coreceptor...

  20. Mangiferin inhibits macrophage classical activation via downregulating interferon regulatory factor 5 expression

    OpenAIRE

    Wei, Zhiquan; YAN Li; Chen, Yixin; Bao, Chuanhong; Deng, Jing; Deng, Jiagang

    2016-01-01

    Mangiferin is a natural polyphenol and the predominant effective component of Mangifera indica Linn. leaves. For hundreds of years, Mangifera indica Linn. leaf has been used as an ingredient in numerous traditional Chinese medicine preparations for the treatment of bronchitis. However, the pharmacological mechanism of mangiferin in the treatment of bronchitis remains to be elucidated. Macrophage classical activation is important role in the process of bronchial airway inflammation, and interf...

  1. Inhibition of lanthanide nanocrystal-induced inflammasome activation in macrophages by a surface coating peptide through abrogation of ROS production and TRPM2-mediated Ca(2+) influx.

    Science.gov (United States)

    Yao, Han; Zhang, Yunjiao; Liu, Liu; Xu, Youcui; Liu, Xi; Lin, Jun; Zhou, Wei; Wei, Pengfei; Jin, Peipei; Wen, Long-Ping

    2016-11-01

    Lanthanide-based nanoparticles (LNs) hold great promise in medicine. A variety of nanocrystals, including LNs, elicits potent inflammatory response through activation of NLRP3 inflammasome. We have previously identified an LNs-specific surface coating peptide RE-1, with the sequence of 'ACTARSPWICG', which reduced nanocrystal-cell interaction and abrogated LNs-induced autophagy and toxicity in both HeLa cells and liver hepatocytes. Here we show that RE-1 coating effectively inhibited LNs-induced inflammasome activation, mostly mediated by NLRP3, in mouse bone marrow derived macrophage (BMDM) cells, human THP-1 cells and mouse peritoneal macrophages and also reduced LNs-elicited inflammatory response in vivo. RE-1 coating had no effect on cellular internalization of LNs in BMDM cells, in contrast to the situation in HeLa cells where cell uptake of LNs was significantly inhibited by RE-1. To elucidate the molecular mechanism underlying the inflammasome-inhibiting effect of RE-1, we assessed several parameters known to influence nanocrystal-induced NLRP3 inflammasome activation. RE-1 coating did not reduce potassium efflux, which occurred after LNs treatment in BMDM cells and was necessary but insufficient for LNs-induced inflammasome activation. RE-1 did decrease lysosomal damage induced by LNs, but the inhibitor of cathepsin B did not affect LNs-elicited caspase 1 activation and IL-1β release, suggesting that lysosomal damage was not critically important for LNs-induced inflammasome activation. On the other hand, LNs-induced elevation of intracellular reactive oxygen species (ROS), critically important for inflammasome activation, was largely abolished by RE-1 coating, with the reduction on NADPH oxidase-generated ROS playing a more prominent role for RE-1's inflammasome-inhibiting effect than the reduction on mitochondria-generated ROS. ROS generation further triggered Ca(2+) influx, an event that was mediated by Transient Receptor Potential M2 (TRPM2) and was

  2. Extract of the seed coat of Tamarindus indica inhibits nitric oxide production by murine macrophages in vitro and in vivo.

    Science.gov (United States)

    Komutarin, T; Azadi, S; Butterworth, L; Keil, D; Chitsomboon, B; Suttajit, M; Meade, B J

    2004-04-01

    The seed coat extract of Tamarindus indica, a polyphenolic flavonoid, has been shown to have antioxidant properties. The present studies investigated the inhibitory effect of the seed coat extract of T. indica on nitric oxide production in vitro using a murine macrophage-like cell line, RAW 264.7, and in vitro and in vivo using freshly isolated B6C3F1 mouse peritoneal macrophages. In vitro exposure of RAW 264.7 cells or peritoneal macrophages to 0.2-200 microg/mL of T. indica extract significantly attenuated (as much as 68%) nitric oxide production induced by lipopolysaccharide (LPS) and interferon gamma (IFN-gamma) in a concentration-dependent manner. In vivo administration of T. indica extract (100-500 mg/kg) to B6C3F1 mice dose-dependently suppressed TPA, LPS and/or IFN-gamma induced production of nitric oxide in isolated mouse peritoneal macrophages in the absence of any effect on body weight. Exposure to T. indica extract had no effect on cell viability as assessed by the MTT assay. In B6C3F1 mice, preliminary safety studies demonstrated a decrease in body weight at only the highest dose tested (1000 mg/kg) without alterations in hematology, serum chemistry or selected organ weights or effects on NK cell activity. A significant decrease in body weight was observed in BALB/c mice exposed to concentrations of extract of 250 mg/kg or higher. Oral exposure of BALB/c mice to T. indica extract did not modulate the development of T cell-mediated sensitization to DNFB or HCA as measured by the local lymph node assay, or dermal irritation to nonanoic acid or DNFB. These studies suggest that in mice, T. indica extract at concentrations up to 500 mg/kg may modulate nitric oxide production in the absence of overt acute toxicity.

  3. Macrophage inflammatory protein 1alpha inhibits postentry steps of human immunodeficiency virus type 1 infection via suppression of intracellular cyclic AMP.

    Science.gov (United States)

    Amella, Carol-Ann; Sherry, Barbara; Shepp, David H; Schmidtmayerova, Helena

    2005-05-01

    Primary isolates of human immunodeficiency virus type 1 (HIV-1) predominantly use chemokine receptor CCR5 to enter target cells. The natural ligands of CCR5, the beta-chemokines macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, and RANTES, interfere with HIV-1 binding to CCR5 receptors and decrease the amount of virions entering cells. Although the inhibition of HIV-1 entry by beta-chemokines is well documented, their effects on postentry steps of the viral life cycle and on host cell components that control the outcome of infection after viral entry are not well defined. Here, we show that all three beta-chemokines, and MIP-1alpha in particular, inhibit postentry steps of the HIV-1 life cycle in primary lymphocytes, presumably via suppression of intracellular levels of cyclic AMP (cAMP). Productive HIV-1 infection of primary lymphocytes requires cellular activation. Cell activation increases intracellular cAMP, which is required for efficient synthesis of proviral DNA during early steps of viral infection. Binding of MIP-1alpha to cognate receptors decreases activation-induced intracellular cAMP levels through the activation of inhibitory G proteins. Furthermore, inhibition of one of the downstream targets of cAMP, cAMP-dependent PKA, significantly inhibits synthesis of HIV-1-specific DNA without affecting virus entry. These data reveal that beta-chemokine-mediated inhibition of virus replication in primary lymphocytes combines inhibitory effects at the entry and postentry levels and imply the involvement of beta-chemokine-induced signaling in postentry inhibition of HIV-1 infection.

  4. N-Acetyl-L-cysteine and pyrrolidine dithiocarbamate inhibited nuclear factor-кB activation in alveolar macrophages by different mechanisms

    Institute of Scientific and Technical Information of China (English)

    Ya-qing LI; Zhen-xiang ZHANG; Yong-jian XU; Wang NI; Shi-xin CHEN; Zhao YANG; Dan MA

    2006-01-01

    Aim:To study the effects of N-acetyl-L-cysteine(NAC)and pyrrolidine dithiocarbamate(PDTC)on the phosphorylation of IκB kinase(IKK)β,IKKα,and IκBa in alveolar macrophages(AM),and to explore the pharmacological mechanisms of NAC and PDTC as inhibitors of NF-κB activation.Methods:AM were collected from bronchoalveolar lavage fluid from the patients with chronic obstructive pulmonary disease.The AM were incubated for 1.5h with NAC and PDTC,and then stimulated for 90 min by either tumor necrosis factor(TNF)-α or interleukin(IL)-1.Western blotting was used to detect the protein phosphorylation levels of IKKβ,IKKα,and IκBα.NF-κB activity was analyzed by using an electrophoretic mobility shift assay.Resuits:NAC inhibited the phosphorylation of IKKβ,IKKα,and IκBα induced by TNF-α,but had no effect on the phosphorylation of IKKβ,IKKα and IκBα induced by IL-1.PDTC did not inhibit the phosphorylation of IκBα induced by TNF-α or IL-1.Similarly,NAC inhibited the activation of NF-κB induced by TNF-α,but had no effect on the activation of NF-κB induced by IL-1.PDTC significantly inhibited the activation of NF-κB induced by TNF-α and IL-1.The electrophoretic mobility shift assay also showed that PDTC and NAC do not directly inhibit NF-κB DNA binding activity in vitro.Conclusion:PDTC prevents the degradation of IκBα via the ubiquitylation-proteasome proteolytic pathway.NAC can inhibit the processes upstream of IKK activation induced by TNF-α,which results in the decline of NF-κB activity.

  5. Anti-inflammatory activity of atractylenolide III through inhibition of nuclear factor-κB and mitogen-activated protein kinase pathways in mouse macrophages.

    Science.gov (United States)

    Ji, Guang-Quan; Chen, Ren-Qiong; Wang, Ling

    2016-01-01

    To elucidate the anti-inflammatory mechanisms involved, we investigated the effects of atractylenolide III (ATL-III) on cytokine expression, extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 mitogen-activated protein kinase (p38), C-Jun-N-terminal protein kinase1/2 (JNK1/2) and nuclear factor-κB (NF-κB) pathways in lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophages. Macrophages were incubated with various concentrations (0, 25, 50, 100 μM) of ATL-III and/or LPS (1 μg/mL) for 24 h. The production of nitric oxide (NO) was determined by the Greiss reagent. The production of tumor necrosis factor alpha (TNF-α), prostaglandin E2 (PGE2) and interleukin 6 (IL-6) was determined by enzyme-linked immunosorbent assay (ELISA). Furthermore, macrophages were treated with ATL-III (0, 25, 100 μM) for 1 h and then stimulated by LPS. NF-κB, p38, JNK1/2 and ERK1/2 were determined by western blotting. We found ATL-III showed no inhibitory effect on cell proliferation at concentrations ranging from 1 μM to 100 μM. In addition, ATL-III decreased the release of NO, TNF-α, PGE2 and IL-6 in a dose-dependent manner and showed statistically significant at concentrations of 50 μM and 100 μM as well as cyclooxygenase-2 (COX-2) expression. Furthermore, ATL-III suppressed the transcriptional activity of NF-κB. ATL-III also inhibited the activation of ERK1/2, p38 and JNK1/2 in LPS-treated macrophages and showed statistically significant at concentrations of 25 μM and 100 μM. These data suggest that ATL-III shows an anti-inflammatory effect by suppressing the release of NO, PGE2, TNF-α and IL-6 related to the NF-κB- and MAPK-signaling pathways.

  6. Adipocyte Fatty Acid Binding Protein Potentiates Toxic Lipids-Induced Endoplasmic Reticulum Stress in Macrophages via Inhibition of Janus Kinase 2-dependent Autophagy

    Science.gov (United States)

    Hoo, Ruby L. C.; Shu, Lingling; Cheng, Kenneth K. Y.; Wu, Xiaoping; Liao, Boya; Wu, Donghai; Zhou, Zhiguang; Xu, Aimin

    2017-01-01

    Lipotoxicity is implicated in the pathogenesis of obesity-related inflammatory complications by promoting macrophage infiltration and activation. Endoplasmic reticulum (ER) stress and adipocyte fatty acid binding protein (A-FABP) play key roles in obesity and mediate inflammatory activity through similar signaling pathways. However, little is known about their interplay in lipid-induced inflammatory responses. Here, we showed that prolonged treatment of palmitic acid (PA) increased ER stress and expression of A-FABP, which was accompanied by reduced autophagic flux in macrophages. Over-expression of A-FABP impaired PA-induced autophagy associating with enhanced ER stress and pro-inflammatory cytokine production, while genetic ablation or pharmacological inhibition of A-FABP reversed the conditions. PA-induced expression of autophagy-related protein (Atg)7 was attenuated in A-FABP over-expressed macrophages, but was elevated in A-FABP-deficient macrophages. Mechanistically, A-FABP potentiated the effects of PA by inhibition of Janus Kinase (JAK)2 activity, thus diminished PA-induced Atg7 expression contributing to impaired autophagy and further augmentation of ER stress. These findings suggest that A-FABP acts as autophagy inhibitor to instigate toxic lipids-induced ER stress through inhibition of JAK2-dependent autophagy, which in turn triggers inflammatory responses in macrophages. A-FABP-JAK2 axis may represent an important pathological pathway contributing to obesity-related inflammatory diseases. PMID:28094778

  7. Schisandrin B inhibits cell growth and induces cellular apoptosis and autophagy in mouse hepatocytes and macrophages: implications for its hepatotoxicity.

    Science.gov (United States)

    Zhang, Yi; Zhou, Zhi-Wei; Jin, Hua; Hu, Chengbin; He, Zhi-Xu; Yu, Zhi-Ling; Ko, Kam-Ming; Yang, Tianxin; Zhang, Xueji; Pan, Si-Yuan; Zhou, Shu-Feng

    2015-01-01

    A number of drugs and herbal compounds have been documented to cause hepatoxicity. Schisandrin B (Sch B) is an active dibenzocyclooctadiene isolated from Schisandrae fructus, with a wide array of pharmacological activities. However, the potential hepatotoxicity of Sch B is a major safety concern, and the underlying mechanism for Sch B-induced liver toxic effects is not fully elucidated. In the present study, we aimed to investigate the liver toxic effects and the molecular mechanisms of Sch B in mouse liver and macrophage cells. The results have shown that Sch B exhibits potent grow inhibitory, proapoptotic, and proautophagic effects in AML-12 and RAW 264.7 cells. Sch B markedly arrested cells in G1 phase in both cell lines, accompanied by the down-regulation of cyclin dependent kinase 2 (CDK2) and cyclin D1 and up-regulation of p27 Kip1 and checkpoint kinase 1. Furthermore, Sch B markedly increased the apoptosis of AML-12 and RAW 264.7 cells with a decrease in the expression of B-cell lymphoma-extra-large and (Bcl-xl) B-cell lymphoma 2 (Bcl-2), but an increase in the expression of B-cell lymphoma 2-associated X protein (Bax). Sch B promoted the cleavage of caspase 3 and poly-adenosine diphosphate-ribose polymerase (PARP) in both cell lines. Additionally, Sch B significantly induced autophagy of AML-12 and RAW 264.7 cells. Sch B inhibited the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway, as indicated by their altered phosphorylation, contributing to the proautophagic effect of Sch B. Taken together, our findings show that the inducing effects of Sch B on cell cycle arrest, apoptosis, and autophagy may contribute to its liver toxic effects, which might provide a clue for the investigation of the molecular toxic targets and underlying mechanisms for Sch B-induced hepatotoxicity in herbal consumers. More studies are warranted to fully delineate the underlying mechanisms, efficacy, and

  8. 2-Phenylnaphthalene Derivatives Inhibit Lipopolysaccharide-Induced Pro-Inflammatory Mediators by Downregulating of MAPK/NF-κB Pathways in RAW 264.7 Macrophage Cells

    Science.gov (United States)

    Chang, Chi-Fen; Liao, Kang-Chun; Chen, Chung-Hwan

    2017-01-01

    The anti-inflammatory pharmacological effect of eight 2-phenylnaphthalenes (PNAP-1−PNAP-8) on lipopolysaccharide (LPS)-induced RAW 264.7 (a mouse cell line) was investigated. Among them, 6,7-dihydroxy-2-(4′-hydroxyphenyl)naphthalene (PNAP-6) and 2-(4′-aminophenyl)-6,7-dimethoxynaphthalene (PNAP-8) exhibited the best anti-inflammatory activity in this study. PNAP-6 and PNAP-8 not only significantly decreased the expression of inducible nitric oxide synthase and cyclooxygenase-II, but also inhibited the production of nitric oxide, interleukin-6, and tumor necrosis factor-α in LPS stimulated cells. Moreover, PNAP-6 and PNAP-8 inhibited nuclear factor (NF)-κB activation by decreasing the degradation of IκB and nuclear translocation of NF-κB subunit (p65). In addition, PNAP-6 and PNAP-8 also attenuated the phosphorylation of ERK, p38, and JNK. These results suggest that PNAP-6 and PNAP-8 exert anti-inflammatory activities by down regulating NF-κB activation and the mitogen-activated protein kinase signaling pathway in LPS-stimulated Raw 264.7 cells. This is the first study demonstrating that PNAPs can inhibit LPS-induced pro-inflammatory mediators in macrophages cells. PMID:28060845

  9. Ethyl pyruvate inhibits the acetylation and release of HMGB1 via effects on SIRT1/STAT signaling in LPS-activated RAW264.7 cells and peritoneal macrophages.

    Science.gov (United States)

    Kim, Young Min; Park, Eun Jung; Kim, Jung Hwan; Park, Sang Won; Kim, Hye Jung; Chang, Ki Churl

    2016-12-01

    High mobility group box 1 (HMGB1), a cytokine present in the late phase of sepsis, may be a potential target for the treatment of sepsis. For HMGB1 to be actively secreted from macrophages during infections, it must be post-translationally modified. Although ethyl pyruvate (EP), a simple aliphatic ester derived from pyruvic acid, has been shown to inhibit the release of HMGB1 in lipopolysaccharide (LPS)-treated RAW 264.7 cells, the underlying mechanism(s) are not yet clear. We investigated the hypothesis that the upregulation of SIRT1 by EP might promote the deacetylation of HMGB1, which reduces HMGB1 release in LPS-activated macrophages. Our results show that EP induced the expression of the SIRT1 protein in RAW264.7 cells and that it significantly inhibited the LPS-induced acetylation of HMGB1. Transfection with a SIRT1-overexpressing vector resulted in a significant decrease in the acetylation of HMGB1 in LPS-activated RAW264.7 cells relative to control cells. The genetic ablation or the pharmacological inhibition of SIRT1 by sirtinol increased LPS-induced HMGB1 acetylation. Moreover, EP inhibited the acetylation of HMGB1 in peritoneal macrophages treated with LPS. Interestingly, EP significantly reduced the LPS-induced phosphorylation of STAT1, which was significantly reversed by siSIRT1 transfection in RAW264.7 cells, indicating that SIRT1 negatively regulates the phosphorylation of STAT1. Overall, the results show that EP promotes the deacetylation of HMGB1 via the inhibition of STAT1 phosphorylation through the upregulation of SIRT1, which reduces HMGB1 release in LPS-activated RAW264.7 cells. In conclusion, EP might be useful in the treatment of diseases that target HMGB1, such as sepsis. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Corosolic acid ameliorates acute inflammation through inhibition of IRAK-1 phosphorylation in macrophages

    Science.gov (United States)

    Kim, Seung-Jae; Cha, Ji-Young; Kang, Hye Suk; Lee, Jae-Ho; Lee, Ji Yoon; Park, Jae-Hyung; Bae, Jae-Hoon; Song, Dae-Kyu; Im, Seung-Soon

    2016-01-01

    Corosolic acid (CA), a triterpenoid compound isolated from Lagerstroemia speciosa L. (Banaba) leaves, exerts anti-inflammatory effects by regulating phosphorylation of interleukin receptor- associated kinase (IRAK)-2 via the NF-κB cascade. However, the protective effect of CA against endotoxic shock has not been reported. LPS (200 ng/mL, 30 min) induced phosphorylation of IRAK-1 and treatment with CA (10 μM) significantly attenuated this effect. In addition, CA also reduced protein levels of NLRP3 and ASC which are the main components of the inflammasome in BMDMs. LPS-induced inflammasome assembly through activation of IRAK-1 was down-regulated by CA challenge. Treatment with Bay11-7082, an inhibitor of IκB-α, had no effect on CA-mediated inhibition of IRAK-1 activation, indicating that CA-mediated attenuation of IRAK-1 phosphorylation was independent of NF-κB signaling. These results demonstrate that CA ameliorates acute inflammation in mouse BMDMs and CA may be useful as a pharmacological agent to prevent acute inflammation. [BMB Reports 2016; 49(5): 276-281] PMID:26615974

  11. Molecular hydrogen inhibits lipopolysaccharide-triggered NLRP3 inflammasome activation in macrophages by targeting the mitochondrial reactive oxygen species.

    Science.gov (United States)

    Ren, Jian-Dong; Wu, Xiao-Bo; Jiang, Rui; Hao, Da-Peng; Liu, Yi

    2016-01-01

    The NLRP3 inflammasome, an intracellular multi-protein complex controlling the maturation of cytokine interleukin-1β, plays an important role in lipopolysaccharide (LPS)-induced inflammatory cascades. Recently, the production of mitochondrial reactive oxygen species (mtROS) in macrophages stimulated with LPS has been suggested to act as a trigger during the process of NLRP3 inflammasome activation that can be blocked by some mitochondria-targeted antioxidants. Known as a ROS scavenger, molecular hydrogen (H2) has been shown to possess therapeutic benefit on LPS-induced inflammatory damage in many animal experiments. Due to the unique molecular structure, H2 can easily target the mitochondria, suggesting that H2 is a potential antagonist of mtROS-dependent NLRP3 inflammasome activation. Here we have showed that, in mouse macrophages, H2 exhibited substantial inhibitory activity against LPS-initiated NLRP3 inflammasome activation by scavenging mtROS. Moreover, the elimination of mtROS by H2 resultantly inhibited mtROS-mediated NLRP3 deubiquitination, a non-transcriptional priming signal of NLRP3 in response to the stimulation of LPS. Additionally, the removal of mtROS by H2 reduced the generation of oxidized mitochondrial DNA and consequently decreased its binding to NLRP3, thereby inhibiting the NLRP3 inflammasome activation. Our findings have, for the first time, revealed the novel mechanism underlying the inhibitory effect of molecular hydrogen on LPS-caused NLRP3 inflammasome activation, highlighting the promising application of this new antioxidant in the treatment of LPS-associated inflammatory pathological damage.

  12. Red Ginseng Marc Oil Inhibits iNOS and COX-2 via NFκB and p38 Pathways in LPS-Stimulated RAW 264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Woo-Sik Jeong

    2012-11-01

    Full Text Available In this study, we investigated the anti-inflammatory effects of red ginseng marc oil (RMO in the RAW 264.7 macrophage cell line. RMO was prepared by a supercritical CO2 extraction of waste product generated after hot water extraction of red ginseng. RMO significantly inhibited the production of oxidative stress molecules such as nitric oxide and reactive oxygen species in lipopolysaccharide (LPS-activated RAW 264.7 cells. Levels of inflammatory targets including prostaglandin E2, tumor necrosis factor-α, interleukin (IL-1β and IL-6 were also reduced after the treatment with RMO. In addition, RMO diminished the expressions of inducible nitric oxide synthase and cyclooxygenase 2 at both mRNA and protein levels. Blockade of nuclear translocation of the p65 subunit of nuclear factor κB (NFκB was also observed after the treatment of RMO. Furthermore, RMO decreased the phosphorylations of p38 mitogen-activated protein kinase (MAPK and its upstream kinases including MAPK kinases 3/6 (MKK3/6 and TAK 1 (TGF-β activated kinase 1. Gas chromatographic analysis on RMO revealed that RMO contained about 10% phytosterols including sitosterol, stigmasterol and campesterol which may contribute to the anti-inflammatory properties of RMO. Taken together, these results suggest that the anti-inflammatory effect of RMO in LPS-induced RAW 264.7 macrophages could be associated with the inhibition of NFκB transcriptional activity, possibly via blocking the p38 MAPK pathway.

  13. High density lipoprotein (HDL)-associated sphingosine 1-phosphate (S1P) inhibits macrophage apoptosis by stimulating STAT3 activity and survivin expression

    DEFF Research Database (Denmark)

    Feuerborn, Renata; Becker, Susen; Potì, Francesco;

    2016-01-01

    reticulum-dependent apoptosis was induced by exposure of macrophages to etoposide or thapsigargin/fukoidan, respectively. RESULTS: Cell death induced by these compounds was inhibited by S1P as inferred from reduced annexin V binding, TUNEL staining, and caspase 3, 9 and 12 activities. S1P induced expression...

  14. Autocatalytic nitration of prostaglandin endoperoxide synthase-2 by nitrite inhibits prostanoid formation in rat alveolar macrophages.

    Science.gov (United States)

    Schildknecht, Stefan; Karreman, Christiaan; Daiber, Andreas; Zhao, Cheng; Hamacher, Jürg; Perlman, David; Jung, Birgit; van der Loo, Bernd; O'Connor, Peter; Leist, Marcel; Ullrich, Volker; Bachschmid, Markus Michael

    2012-11-15

    Prostaglandin endoperoxide H(2) synthase (PGHS) is a well-known target for peroxynitrite-mediated nitration. In several experimental macrophage models, however, the relatively late onset of nitration failed to coincide with the early peak of endogenous peroxynitrite formation. In the present work, we aimed to identify an alternative, peroxynitrite-independent mechanism, responsible for the observed nitration and inactivation of PGHS-2 in an inflammatory cell model. In primary rat alveolar macrophages stimulated with lipopolysaccharide (LPS), PGHS-2 activity was suppressed after 12 h, although the prostaglandin endoperoxide H(2) synthase (PGHS-2) protein was still present. This coincided with a nitration of the enzyme. Coincubation with a nitric oxide synthase-2 (NOS-2) inhibitor preserved PGHS-2 nitration and at the same time restored thromboxane A(2) (TxA(2)) synthesis in the cells. Formation of reactive oxygen species (ROS) was maximal at 4 h and then returned to baseline levels. Nitrite (NO(2)(-)) production occurred later than ROS generation. This rendered generation of peroxynitrite and the nitration of PGHS-2 unlikely. We found that the nitrating agent was formed from NO(2)(-), independent from superoxide ((•)O(2)(-)). Purified PGHS-2 treated with NO(2)(-) was selectively nitrated on the active site Tyr(371), as identified by mass spectrometry (MS). Exposure to peroxynitrite resulted in the nitration not only of Tyr(371), but also of other tyrosines (Tyr). The data presented here point to an autocatalytic nitration of PGHS-2 by NO(2)(-), catalyzed by the enzyme's endogenous peroxidase activity and indicate a potential involvement of this mechanism in the termination of prostanoid formation under inflammatory conditions.

  15. Prognostic significance of tumor-associated macrophages in solid tumor: a meta-analysis of the literature.

    Directory of Open Access Journals (Sweden)

    Qiong-wen Zhang

    Full Text Available PURPOSE: Tumor associated macrophages (TAMs are considered with the capacity to have both negative and positive effects on tumor growth. The prognostic value of TAM for survival in patients with solid tumor remains controversial. EXPERIMENTAL DESIGN: We conducted a meta-analysis of 55 studies (n = 8,692 patients that evaluated the correlation between TAM (detected by immunohistochemistry and clinical staging, overall survival (OS and disease free survival (DFS. The impact of M1 and M2 type TAM (n = 5 on survival was also examined. RESULTS: High density of TAM was significantly associated with late clinical staging in patients with breast cancer [risk ratio (RR  = 1.20 (95% confidence interval (CI, 1.14-1.28] and bladder cancer [RR = 3.30 (95%CI, 1.56-6.96] and with early clinical staging in patients with ovarian cancer [RR = 0.52 (95%CI, 0.35-0.77]. Negative effects of TAM on OS was shown in patients with gastric cancer [RR = 1.64 (95%CI, 1.24-2.16], breast cancer [RR = 8.62 (95%CI, 3.10-23.95], bladder cancer [RR = 5.00 (95%CI, 1.98-12.63], ovarian cancer [RR = 2.55 (95%CI, 1.60-4.06], oral cancer [RR = 2.03 (95%CI, 1.47-2.80] and thyroid cancer [RR = 2.72 (95%CI, 1.26-5.86],and positive effects was displayed in patients with colorectal cancer [RR = 0.64 (95%CI, 0.43-0.96]. No significant effect was showed between TAM and DFS. There was also no significant effect of two phenotypes of TAM on survival. CONCLUSIONS: Although some modest bias cannot be excluded, high density of TAM seems to be associated with worse OS in patients with gastric cancer, urogenital cancer and head and neck cancer, with better OS in patients with colorectal cancer.

  16. Inhibition of LPS-induced TNF-α and NO production in mouse macrophage and inflammatory response in rat animal models by a novel Ayurvedic formulation, BV-9238.

    Science.gov (United States)

    Dey, Debendranath; Chaskar, Sunetra; Athavale, Nitin; Chitre, Deepa

    2014-10-01

    Rheumatoid arthritis is a chronic crippling disease, where protein-based tumor necrosis factor-alpha (TNF-α) inhibitors show significant relief, but with potentially fatal side effects. A need for a safe, oral, cost-effective small molecule or phyto-pharmaceutical is warranted. BV-9238 is an Ayurvedic poly-herbal formulation containing specialized standardized extracts of Withania somnifera, Boswellia serrata, Zingiber officinale and Curcuma longa. The anti-inflammatory and anti-arthritic effects of BV-9238 were evaluated for inhibition of TNF-α and nitric oxide (NO) production, in lipopolysaccharide-stimulated, RAW 264.7, mouse macrophage cell line. BV-9238 reduced TNF-α and NO production, without any cytotoxic effects. Subsequently, the formulation was tested in adjuvant-induced arthritis (AIA) and carrageenan-induced paw edema (CPE) rat animal models. AIA was induced in rats by injecting Freund's complete adjuvant intra-dermally in the paw, and BV-9238 and controls were administered orally for 21 days. Arthritic scores in AIA study and inflamed paw volume in CPE study were significantly reduced upon treatment with BV-9238. These results suggest that the anti-inflammatory and anti-arthritic effects of BV-9238 are due to its inhibition of TNF-α, and NO, and this formulation shows promise as an alternate therapy for inflammatory disorders where TNF-α and NO play important roles.

  17. Curcumin Alleviates oxLDL Induced MMP-9 and EMMPRIN Expression through the Inhibition of NF-κB and MAPK Pathways in Macrophages

    Science.gov (United States)

    Cao, Jiatian; Ye, Bozhi; Lin, Lu; Tian, Lei; Yang, Hongbo; Wang, Changqian; Huang, Weijian; Huang, Zhouqing

    2017-01-01

    Rupture of vulnerable atherosclerotic plaques is the leading cause of acute myocardial infarction (AMI) and unstable angina pectoris (UA). However, it still lacks an effective therapy to stabilize the vulnerable atherosclerotic plaques. Numerous reports have shown that upregulation of MMP-9 (matrix metalloproteinase-9) and EMMPRIN (extracellular matrix metalloproteinase inducer) in macrophages is involved in the progression and development of vulnerable plaques. Here we evaluated the impact of curcumin on the expression of MMP-9 and EMMPRIN in macrophages. Macrophages were pretreated with curcumin or specific inhibitors (p38 MAPK inhibitor, NF-κB p65 inhibitor) for 1 h, then cells were cultured with oxLDL for indicated time. Real-time PCR and Western blot analysis were used to evaluate the expression of mRNA and proteins. Translocation of NF-κB p65 was detected by using laser confocal microscopy. Here we showed that curcumin attenuated the MMP-9 and EMMPRIN expression in oxLDL stimulated macrophages. Further studies revealed that curcumin inhibited oxLDL induced NF-κB activation and p38 MAPK phosphorylation. These findings illustrated that curcumin can inhibit the expression of EMMPRIN and MMP-9 in oxLDL stimulated macrophages through down regulation of NF-κB and p38 MAPK signaling pathways, which might be the molecular mechanism for the anti-atherosclerotic effect of curcumin. PMID:28261097

  18. An extract of Phellinus linteus grown on germinated brown rice inhibits inflammation markers in RAW264.7 macrophages by suppressing inflammatory cytokines, chemokines, and mediators and up-regulating antioxidant activity.

    Science.gov (United States)

    Park, Hye-Jin; Han, Eun Su; Park, Dong Ki; Lee, Chan; Lee, Ki Won

    2010-12-01

    The immunomodulatory activity of an organic extract of Phellinus linteus grown on slightly germinated brown rice (PBR) was previously demonstrated. Here, we investigated the possible anti-inflammatory activity of the PBR extract by analyzing its effect on the expression of macrophage-derived cytokines, chemokines, and mediator genes that participate in immune and inflammatory responses and diseases. The extract profoundly inhibited the induction of cytokines and chemokines, including tumor necrosis factor-α, chemokine (C-X-C motif) ligand-10, granulocyte-macrophage colony-stimulating factor, and interleukin-6, in lipopolysaccharide (LPS)-stimulated RAW264.7 mouse macrophage cells. It also greatly inhibited LPS-stimulated production of nitric oxide (NO) and prostaglandin E(2) in RAW264.7 cells by suppressing the expression of inducible NO synthase and cyclooxygenase-2. PBR extract inhibited NO production with a twofold lower half-maximal inhibitory concentration value than P. linteus extract. To elucidate the underlying mechanism of action, we examined the effect of the PBR extract on the LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs) in RAW264.7 cells. PBR extract greatly inhibited extracellular signal-regulated kinase and c-Jun N-terminal kinase phosphorylation and slightly inhibited p38 MAPK phosphorylation. It also significantly increased intracellular glutathione peroxidase activity and heme oxygenase-1 protein expression. Thus, the PBR extract has anti-inflammatory activity in LPS-stimulated RAW264.7 cells by virtue of its ability to suppress the production of inflammatory cytokines and chemokines via inhibition of MAPK activation and up-regulation of antioxidant activities.

  19. Systemic and Cardiac Depletion of M2 Macrophage through CSF-1R Signaling Inhibition Alters Cardiac Function Post Myocardial Infarction

    OpenAIRE

    Anne-Laure Leblond; Kerstin Klinkert; Kenneth Martin; Turner, Elizebeth C.; Arun H Kumar; Tara Browne; Caplice, Noel M.

    2015-01-01

    The heart hosts tissue resident macrophages which are capable of modulating cardiac inflammation and function by multiple mechanisms. At present, the consequences of phenotypic diversity in macrophages in the heart are incompletely understood. The contribution of cardiac M2-polarized macrophages to the resolution of inflammation and repair response following myocardial infarction remains to be fully defined. In this study, the role of M2 macrophages was investigated utilising a specific CSF-1...

  20. High density lipoprotein (HDL)-associated sphingosine 1-phosphate (S1P) inhibits macrophage apoptosis by stimulating STAT3 activity and survivin expression.

    Science.gov (United States)

    Feuerborn, Renata; Becker, Susen; Potì, Francesco; Nagel, Petra; Brodde, Martin; Schmidt, Harmut; Christoffersen, Christina; Ceglarek, Uta; Burkhardt, Ralph; Nofer, Jerzy-Roch

    2017-02-01

    Macrophage apoptosis is critically involved in atherosclerosis. We here examined the effect of anti-atherogenic high density lipoprotein (HDL) and its component sphingosine-1-phosphate (S1P) on apoptosis in RAW264.7 murine macrophages. Mitochondrial or endoplasmic reticulum-dependent apoptosis was induced by exposure of macrophages to etoposide or thapsigargin/fukoidan, respectively. Cell death induced by these compounds was inhibited by S1P as inferred from reduced annexin V binding, TUNEL staining, and caspase 3, 9 and 12 activities. S1P induced expression of the inhibitor of apoptosis protein (IAP) family proteins cIAP1, cIAP2 and survivin, but only the inhibitor of survivin expression YM155 and not the cIAP1/2 blocker GDC0152 reversed the inhibitory effect of S1P on apoptosis. Moreover, S1P activated signal transducer and activator of transcription 3 (STAT3) and Janus kinase 2 (JAK2) and the stimulatory effect of S1P on survivin expression and inhibitory effects on apoptosis were attenuated by STAT3 or JAK2 inhibitors, S3I-201 or AG490, respectively. The effects of S1P on STAT3 activation, survivin expression and macrophage apoptosis were emulated by HDL, HDL lipids, and apolipoprotein (apo) M-containing HDL, but not by apoA-I or HDL deprived of S1P or apoM. In addition, JTE013 and CAY10444, S1P receptor 2 and 3 antagonists, respectively, compromised the S1P and HDL capacities to stimulate STAT3 activation and survivin expression, and to inhibit apoptosis. HDL-associated S1P inhibits macrophage apoptosis by stimulating STAT3 activity and survivin expression. The suppression of macrophage apoptosis may represent a novel mechanism utilized by HDL to exert its anti-atherogenic effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Targeting colon cancer cell NF-κB promotes an anti-tumour M1-like macrophage phenotype and inhibits peritoneal metastasis.

    Science.gov (United States)

    Ryan, A E; Colleran, A; O'Gorman, A; O'Flynn, L; Pindjacova, J; Lohan, P; O'Malley, G; Nosov, M; Mureau, C; Egan, L J

    2015-03-19

    In a model of peritoneal metastasis in immune-competent mice, we show that nuclear factor (NF)-κB inhibition in CT26 colon cancer cells prevents metastasis. NF-κB inhibition, by stable overexpression of IκB-α super-repressor, induced differential polarization of co-cultured macrophages to an M1-like anti-tumour phenotype in vitro. NF-κB-deficient cancer cell-conditioned media (CT26/IκB-α SR) induced interleukin (IL)-12 and nitric oxide (NO) synthase (inducible NO synthase (iNOS)) expression in macrophages. Control cell (CT26/EV) conditioned media induced high levels of IL-10 and arginase in macrophages. In vivo, this effect translated to reduction in metastasis in mice injected with CT26/ IκB-α SR cells and was positively associated with increased CD8(+)CD44(+)CD62L(-) and CD4(+)CD44(+)CD62L(-) effector T cells. Furthermore, inhibition of NF-κB activity induced high levels of NO in infiltrating immune cells and decreases in matrix metalloproteinase-9 expression, simultaneous with increases in tissue inhibitor of metalloproteinases 1 and 2 within tumours. CT26/IκB-α SR tumours displayed increased pro-inflammatory gene expression, low levels of angiogenesis and extensive intratumoral apoptosis, consistent with the presence of an anti-tumour macrophage phenotype. Macrophage depletion reduced tumour size in CT26/EV-injected animals and increased tumour size in CT26/IκB-α SR cells compared with untreated tumours. Our data demonstrate, for the first time, that an important implication of targeting tumour cell NF-κB is skewing of macrophage polarization to an anti-tumour phenotype. This knowledge offers novel therapeutic opportunities for anticancer treatment.

  2. Cold Atmospheric Plasma Inhibits HIV-1 Replication in Macrophages by Targeting Both the Virus and the Cells

    Science.gov (United States)

    Volotskova, Olga; Dubrovsky, Larisa; Keidar, Michael; Bukrinsky, Michael

    2016-01-01

    Cold atmospheric plasma (CAP) is a specific type of partially ionized gas that is less than 104°F at the point of application. It was recently shown that CAP can be used for decontamination and sterilization, as well as anti-cancer treatment. Here, we investigated the effects of CAP on HIV-1 replication in monocyte-derived macrophages (MDM). We demonstrate that pre-treatment of MDM with CAP reduced levels of CD4 and CCR5, inhibiting virus-cell fusion, viral reverse transcription and integration. In addition, CAP pre-treatment affected cellular factors required for post-entry events, as replication of VSV-G-pseudotyped HIV-1, which by-passes HIV receptor-mediated fusion at the plasma membrane during entry, was also inhibited. Interestingly, virus particles produced by CAP-treated cells had reduced infectivity, suggesting that the inhibitory effect of CAP extended to the second cycle of infection. These results demonstrate that anti-HIV activity of CAP involves the effects on target cells and the virus, and suggest that CAP may be considered for potential application as an anti-HIV treatment. PMID:27783659

  3. Fucoidan inhibits CCL22 production through NF-κB pathway in M2 macrophages: a potential therapeutic strategy for cancer

    Science.gov (United States)

    Sun, Jia; Sun, Jintang; Song, Bingfeng; Zhang, Lin; Shao, Qianqian; Liu, Yanguo; Yuan, Daoying; Zhang, Yun; Qu, Xun

    2016-01-01

    In tumor microenvironment, macrophages as a polarized M2 population promote tumor progression via releasing multiple cytokines and chemokines. A brown seaweed fucose-rich polysaccharide, fucoidan has antitumor activity and immune modulation through affecting tumor cells and lymphocytes. Here, we focused on the effect of fucoidan on macrophages especially M2 subtype. Our results demonstrated that fucoidan down-regulated partial cytokines and chemokines, especially a M2-type chemokine CCL22. Furthermore, fucoidan inhibited tumor cells migration and CD4+ T lymphocytes, especially Treg cells, recruitment induced by M2 macrophages conditioned medium through suppression of CCL22. Mechanismly, fucoidan inhibited CCL22 via suppressing p65-NF-κB phosphorylation and nuclear translocation. In addition, p38-MAPK and PI3K-AKT also affected the expression of CCL22 through differential modulation of NF-κB transcriptional activity. Taken together, we reveal an interesting result that fucoidan can inhibit tumor cell migration and lymphocytes recruitment by suppressing CCL22 in M2 macrophages via NF-κB-dependent transcription, which may be a novel and promising mechanism for tumor immunotherapy. PMID:27775051

  4. Acute exposure to apolipoprotein A1 inhibits macrophage chemotaxis in vitro and monocyte recruitment in vivo

    Science.gov (United States)

    Iqbal, Asif J; Barrett, Tessa J; Taylor, Lewis; McNeill, Eileen; Manmadhan, Arun; Recio, Carlota; Carmineri, Alfredo; Brodermann, Maximillian H; White, Gemma E; Cooper, Dianne; DiDonato, Joseph A; Zamanian-Daryoush, Maryam; Hazen, Stanley L; Channon, Keith M

    2016-01-01

    Apolipoprotein A1 (apoA1) is the major protein component of high-density lipoprotein (HDL) and has well documented anti-inflammatory properties. To better understand the cellular and molecular basis of the anti-inflammatory actions of apoA1, we explored the effect of acute human apoA1 exposure on the migratory capacity of monocyte-derived cells in vitro and in vivo. Acute (20–60 min) apoA1 treatment induced a substantial (50–90%) reduction in macrophage chemotaxis to a range of chemoattractants. This acute treatment was anti-inflammatory in vivo as shown by pre-treatment of monocytes prior to adoptive transfer into an on-going murine peritonitis model. We find that apoA1 rapidly disrupts membrane lipid rafts, and as a consequence, dampens the PI3K/Akt signalling pathway that coordinates reorganization of the actin cytoskeleton and cell migration. Our data strengthen the evidence base for therapeutic apoA1 infusions in situations where reduced monocyte recruitment to sites of inflammation could have beneficial outcomes. DOI: http://dx.doi.org/10.7554/eLife.15190.001 PMID:27572261

  5. DNAzymes targeting the icl gene inhibit ICL expression and decrease Mycobacterium tuberculosis survival in macrophages.

    Science.gov (United States)

    Li, Junming; Zhu, Daoyin; Yi, Zhengjun; He, Yongli; Chun, Yang; Liu, Yehua; Li, Na

    2005-01-01

    Latent infection with Mycobacterium tuberculosis presents a big obstacle for tuberculosis therapy. In this study, we investigated the effects of sequence-specific DNAzymes targeting the mRNA of isocitrate lyase (ICL), an enzyme playing a pivotal role in the metabolism of M. tuberculosis in the latent state, on the expression of ICL and survival of M. tuberculosis. In vitro studies showed that four of five designed DNAzymes, DZ1, DZ3, DZ4, and DZ5 could cleave icl mRNA efficiently and specifically. Treatment of virulent M. tuberculosis with 5microM DZ4 plus a subinhibitory concentration of isoniazid (INH) decreased ICL expression and the survival of M. tuberculosis in macrophages but had no obvious influence on the growth of M. tuberculosis in vitro. This study demonstrates that using INH to soften the cell wall of M. tuberculosis and help the entry of biomolecules is an efficient method of improving the uptake of DNAzymes. Silencing the icl gene by DNAzyme is a promising method to combat latent infection of tuberculosis.

  6. Resveratrol and its metabolites inhibit pro-inflammatory effects of lipopolysaccharides in U-937 macrophages in plasma-representative concentrations.

    Science.gov (United States)

    Walker, Jessica; Schueller, Katharina; Schaefer, Lisa-Marie; Pignitter, Marc; Esefelder, Laura; Somoza, Veronika

    2014-01-01

    Resveratrol has been shown to exploit various biological activities, including an anti-inflammatory activity. However, resveratrol is metabolized by phase II enzymes post-absorption to predominantly form glucuronides and sulfates. To investigate the anti-inflammatory effects of resveratrol and its dominating sulfated and glucuronated metabolites formed in vivo, U-937 macrophages were chosen as an immune-competent model system, known to release cytokines upon lipopolysaccharide stimulation. U-937 cells were stimulated with lipopolysaccharides from Escherichia coli (E. coli-LPS) to evoke an inflammatory reaction, and pre- or co-incubated with 1 or 10 μM of resveratrol (RES), resveratrol-3-sulfate (R3S), resveratrol-disulfates (RDS), resveratrol-3-glucuronide or resveratrol-4'-glucuronide. Time dependent gene expression of IL-6, IL-1α/β and IL-1R by qPCR was studied at 1 h, 3 h, 6 h, 9 h, and 24 h of incubation, and the release of IL-6 and TNF-α, after 6 h was analysed by means of non-magnetic or magnetic bead analysis. As a result, 10 μM resveratrol completely inhibited the E. coli-LPS-induced release of IL-6, while resveratrol-3-sulfate and resveratrol-disulfates decreased it by respective 84.2 ± 29.4% and 52.3 ± 39.5%. Whereas TNF-α release was reduced by 48.1 ± 15.4%, 33.0 ± 10.0% and 46.7 ± 8.7% by RES, R3S and RDS, respectively. These results show that not only resveratrol but also resveratrol-3-sulfate and resveratrol-disulfates exhibit an anti-inflammatory potential by counteracting an inflammatory challenge in U-937 macrophages at plasma representative concentrations.

  7. Punicalagin inhibits inflammation in LPS-induced RAW264.7 macrophages via the suppression of TLR4-mediated MAPKs and NF-κB activation.

    Science.gov (United States)

    Xu, Xiaolong; Yin, Peng; Wan, Changrong; Chong, Xinlu; Liu, Mingjiang; Cheng, Peng; Chen, Jiajia; Liu, Fenghua; Xu, Jianqin

    2014-06-01

    Punicalagin (2,3,hexahydroxydiphenoyl-gallagyl-D-glucose and referred to as PUN) is a bioactive ellagitannin isolated from pomegranate, which is widely used for the treatment of inflammatory bowel disease (IBD), diarrhea, and ulcers in Chinese traditional medicine. In this study, we detected the anti-inflammation potentials of PUN in lipopolysaccharide (LPS)-induced macrophages and tried to uncover the underlying mechanism. Results demonstrated that PUN (25, 50, or 100 μM) treatment could significantly decrease the LPS-induced production of nitric oxide), prostaglandin E2 (PGE2), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in RAW264.7 cells. Molecular research showed that PUN inhibited the activation of upstream mediator nuclear factor-κB by suppressing the phosphorylation of IκBα and p65. Results also indicated that PUN could suppress the phosphorylation of mitogen-activated protein kinase including p38, c-Jun N-terminal kinase, and extracellular signal-regulated kinase. In conclusion, we observed that PUN could inhibit LPS-induced inflammation, and it may be a potential choice for the treatment of inflammation diseases.

  8. Ketamine inhibits tumor necrosis factor-alpha and interleukin-6 gene expressions in lipopolysaccharide-stimulated macrophages through suppression of toll-like receptor 4-mediated c-Jun N-terminal kinase phosphorylation and activator protein-1 activation.

    Science.gov (United States)

    Wu, Gone-Jhe; Chen, Ta-Liang; Ueng, Yune-Fang; Chen, Ruei-Ming

    2008-04-01

    Our previous study showed that ketamine, an intravenous anesthetic agent, has anti-inflammatory effects. In this study, we further evaluated the effects of ketamine on the regulation of tumor necrosis factor-alpha (TNF-alpha) and interlukin-6 (IL-6) gene expressions and its possible signal-transducing mechanisms in lipopolysaccharide (LPS)-activated macrophages. Exposure of macrophages to 1, 10, and 100 microM ketamine, 100 ng/ml LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. A concentration of 1000 microM of ketamine alone or in combined treatment with LPS caused significant cell death. Administration of LPS increased cellular TNF-alpha and IL-6 protein levels in concentration- and time-dependent manners. Meanwhile, treatment with ketamine concentration- and time-dependently alleviated the enhanced effects. LPS induced TNF-alpha and IL-6 mRNA syntheses. Administration of ketamine at a therapeutic concentration (100 microM) significantly inhibited LPS-induced TNF-alpha and IL-6 mRNA expressions. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA into macrophages decreased cellular TLR4 levels. Co-treatment of macrophages with ketamine and TLR4 siRNA decreased the LPS-induced TNF-alpha and IL-6 productions more than alone administration of TLR4 siRNA. LPS stimulated phosphorylation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos from the cytoplasm to nuclei. However, administration of ketamine significantly decreased LPS-induced activation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos. LPS increased the binding of nuclear extracts to activator protein-1 consensus DNA oligonucleotides. Administration of ketamine significantly ameliorated LPS-induced DNA binding activity of activator protein-1. Therefore, a clinically relevant concentration of ketamine can inhibit TNF-alpha and IL-6 gene expressions in LPS-activated macrophages. The suppressive mechanisms occur through

  9. Graft-Infiltrating Macrophages Adopt an M2 Phenotype and Are Inhibited by Purinergic Receptor P2X7 Antagonist in Chronic Rejection.

    Science.gov (United States)

    Wu, C; Zhao, Y; Xiao, X; Fan, Y; Kloc, M; Liu, W; Ghobrial, R M; Lan, P; He, X; Li, X C

    2016-09-01

    Macrophages exhibit diverse phenotypes and functions; they are also a major cell type infiltrating chronically rejected allografts. The exact phenotypes and roles of macrophages in chronic graft loss remain poorly defined. In the present study, we used a mouse heart transplant model to examine macrophages in chronic allograft rejection. We found that treatment of C57BL/6 mice with CTLA4 immunoglobulin fusion protein (CTLA4-Ig) prevented acute rejection of a Balb/c heart allograft but allowed chronic rejection to develop over time, characterized by prominent neointima formation in the graft. There was extensive macrophage infiltration in the chronically rejected allografts, and the graft-infiltrating macrophages expressed markers associated with M2 cells but not M1 cells. In an in vitro system in which macrophages were polarized into either M1 or M2 cells, we screened phenotypic differences between M1 and M2 cells and identified purinergic receptor P2X7 (P2x7r), an adenosine triphosphate (ATP)-gated ion channel protein that was preferentially expressed by M2 cells. We further showed that blocking the P2x7r using oxidized ATP (oATP) inhibited M2 induction in a dose-dependent fashion in vitro. Moreover, treatment of C57BL/6 recipients with the P2x7r antagonist oATP, in addition to CTLA4-Ig treatment, inhibited graft-infiltrating M2 cells, prevented transplant vasculopathy, and induced long-term heart allografts survival. These findings highlight the importance of the P2x7r-M2 axis in chronic rejection and establish P2x7r as a potential therapeutic target in suppression of chronic rejection.

  10. Immune mechanism and clinical significance of macrophage to medullary hematopoietic injury of immune-related hematocytopenia patients

    Institute of Scientific and Technical Information of China (English)

    SUN Li-fei; HAN Bing; WU Qiang-qiang; ZHANG Xiao-xi; DU Yan-hui; WANG Gui-chen; ZHANG Jin-biao

    2013-01-01

    Background Immune-related hematocytopenia (IRH) is considered to be related with the production of autoantibody,as well as the activation of humoral immunity which is stimulated by B lymphocyte.This study aimed to observe the levels of various cytokines in the blood serum and the in situ active state of macrophage (Mφ) in the medullary hematopoietic microenvironment of IRH patients,and to probe into the immune mechanism and clinical significance of Mφ in hematopoietic cell injury.Methods ELISA is used to detect the IL-4,IL-6,IL-12,IL-17,and IFN-Y levels in the peripheral blood serum of 376 patients in pre-and post-therapy.Cytochemistry and cell immunochemistry methods are used to observe the peroxidase (POX),nonspecific esterase (NSE),hemosiderin granules,and HLA-DR activity of Mφ in the bone marrow of patients.Immunofluorescence is used to observe the expression of hemocyte antihuman globulin IgG antibody,lymphocytes CD4 molecule,Mφ membrane Fcyllreceptor (FcYllR),mannitose receptor (MR),IFN-y,ICAM-1,IL-12,and IL-17A and the formation mechanism of antibody-dependent cell-mediated cytotoxicity (ADCC) hematopoietic cell islands (HI) in the medullary hematopoietic microenvironment of patients.Glucocorticoid is used for treatment on the basis of anti-infection therapy,and gamma globulin stoss therapy is used for the appearance of ADCC-type HI or serious Mφ bloodthirsty phenomenon; if necessary,association of Cyclosporine A (CsA) should be used and chalybeate should be supplemented.Results In the patient group,the levels of IL-4,IL-6,IL-12,IL-17,and IFN-y were increased.After treatment,the cytokine levels gradually became normal.The activated Mφ in the marrow highly expressed NSE and POX,and Mφ swallowed more hemosiderin particles,but the iron in the cytoplasm of immature erythrocytes decreased.The activated Mφ expressed HLA-DR,MR,ICAM-1,IFN-Y,and IL-12.For patients with humoral immunity activation and bacterial infection,Mφ weakly expressed IL-17A but highly

  11. Citrus unshiu flower inhibits LPS-induced iNOS and COX-2 via MAPKs in RAW 264.7 macrophage cells

    Directory of Open Access Journals (Sweden)

    Min-Jin Kim

    2015-12-01

    Full Text Available In the present study, we investigated the effects of Citrus unshiu flower on regulatory mechanisms of cytokines and nitric oxide (NO involved in immunological activity of RAW 264.7 macrophages. Our results indicated that ethyl acetate fraction of Citrus unshiu flower (CUF-EA downregulated LPS-induced nitric oxide (NO synthase (iNOS and cyclooxygenase-2 (COX-2 expression, thereby reducing the production of NO and prostaglandin E2 (PGE2 in LPS-activated RAW 264.7 macrophages. Furthermore, CUF-EA suppressed LPS-induced production of pro-inflammatory cytokines such as interleukin IL-6, and tumor necrosis factor (TNF-α. To elucidate its anti-inflammatory mechanisms, CUF-EA was investigated as an inhibitor of phosphorylation of mitogen-activated protein (MAP kinase in LPS-stimulated RAW 264.7 macrophages. As expected, the phosphorylation of MAP kinases (p38, ERK1/2 and JNK in LPS-stimulated RAW 264.7 macrophages was suppressed by CUF-EA in a dose-dependent manner. These results suggest that the anti-inflammatory properties of CUF-EA might results from inhibition of NO, PGE2, iNOS, COX-2, IL-6 and TNF-α expressions through the down-regulation of phosphorylation of MAPKs in RAW 264.7 macrophages.

  12. Clinical-pathologic significance of CD163 positive macrophage in IgA nephropathy patients with crescents.

    Science.gov (United States)

    Li, Jun; Liu, Chang-Hua; Gao, Bo; Xu, Dao-Liang

    2015-01-01

    CD163, a marker of M2 macrophages, express anti-inflammatory properties. This study aims to investigate the difference of CD163 positive macrophages expression between IgA nephropathy patients with and without crescents. Renal tissues from IgAN patients (n = 24), including IgAN with crescents (n = 10), IgAN without crescents (n = 14), minimal change disease (MCD, as disease control, n = 8) and normal control kidneys (negative control, n = 3), were included in this study. Expressions of CD163 and CD68 in renal tissues were detected by immunohistochemistry or immunofluorescence. Compared with IgAN without crescent, IgAN patients with crescents have lower serum albumin and poor renal function. CD163 was mainly expressed in acute tubulointerstitial lesions. CD163 positive cells accumulate in areas around tubules with RBC casts. CD163 positive cells can also be seen in tubular lumen. CD163 positive cells can be seen in glomerular lesions, including endocapillary hypercellularity, cellular crescent and fibrous-cellular crescent. There were more CD163 positive cells in tubulointerstitial and glomerular lesions in IgAN patients with crescents. CD163 positive cells number in tubulointerstitial tissue was positive correlated with percentage of crescents, proteinuria, and negative correlated with serum albumin, eGFR. CD163 positive cells number in glomeruli was positive correlated with percentage of crescents, and was negative correlated with eGFR. Percentage of crescents was negative correlated with serum albumin, eGFR, and positive correlated with proteinuria. Dual staining showed that CD163 positive cells also expressed CD68. CD163 positive macrophages were involved in active crescent disease, acute tubular injury and glomerular lesions of IgAN with crescents.

  13. A unique anti-CD115 monoclonal antibody which inhibits osteolysis and skews human monocyte differentiation from M2-polarized macrophages toward dendritic cells.

    Science.gov (United States)

    Haegel, Hélène; Thioudellet, Christine; Hallet, Rémy; Geist, Michel; Menguy, Thierry; Le Pogam, Fabrice; Marchand, Jean-Baptiste; Toh, Myew-Ling; Duong, Vanessa; Calcei, Alexandre; Settelen, Nathalie; Preville, Xavier; Hennequi, Marie; Grellier, Benoit; Ancian, Philippe; Rissanen, Jukka; Clayette, Pascal; Guillen, Christine; Rooke, Ronald; Bonnefoy, Jean-Yves

    2013-01-01

    Cancer progression has been associated with the presence of tumor-associated M2-macrophages (M2-TAMs) able to inhibit anti-tumor immune responses. It is also often associated with metastasis-induced bone destruction mediated by osteoclasts. Both cell types are controlled by the CD115 (CSF-1R)/colony-stimulating factor-1 (CSF-1, M-CSF) pathway, making CD115 a promising target for cancer therapy. Anti-human CD115 monoclonal antibodies (mAbs) that inhibit the receptor function have been generated in a number of laboratories. These mAbs compete with CSF-1 binding to CD115, dramatically affecting monocyte survival and preventing osteoclast and macrophage differentiation, but they also block CD115/CSF-1 internalization and degradation, which could lead to potent rebound CSF-1 effects in patients after mAb treatment has ended. We thus generated and selected a non-ligand competitive anti-CD115 mAb that exerts only partial inhibitory effects on CD115 signaling without blocking the internalization or the degradation of the CD115/CSF-1 complex. This mAb, H27K15, affects monocyte survival only minimally, but downregulates osteoclast differentiation and activity. Importantly, it inhibits monocyte differentiation to CD163(+)CD64(+) M2-polarized suppressor macrophages, skewing their differentiation toward CD14(-)CD1a(+) dendritic cells (DCs). In line with this observation, H27K15 also drastically inhibits monocyte chemotactic protein-1 secretion and reduces interleukin-6 production; these two molecules are known to be involved in M2-macrophage recruitment. Thus, the non-depleting mAb H27K15 is a promising anti-tumor candidate, able to inhibit osteoclast differentiation, likely decreasing metastasis-induced osteolysis, and able to prevent M2 polarization of TAMs while inducing DCs, hence contributing to the creation of more efficient anti-tumor immune responses.

  14. Different Regulation of Interleukin-1 Production and Activity in Monocytes and Macrophages: Innate Memory as an Endogenous Mechanism of IL-1 Inhibition

    Directory of Open Access Journals (Sweden)

    Mariusz P. Madej

    2017-06-01

    Full Text Available Production and activity of interleukin (IL-1β are kept under strict control in our body, because of its powerful inflammation-promoting capacity. Control of IL-1β production and activity allows IL-1 to exert its defensive activities without causing extensive tissue damage. Monocytes are the major producers of IL-1β during inflammation, but they are also able to produce significant amounts of IL-1 inhibitors such as IL-1Ra and the soluble form of the decoy receptor IL-1R2, in an auto-regulatory feedback loop. Here, we investigated how innate immune memory could modulate production and activity of IL-1β by human primary monocytes and monocyte-derived tissue-like/deactivated macrophages in vitro. Cells were exposed to Gram-negative (Escherichia coli and Gram-positive (Lactobacillus acidophilus bacteria for 24 h, then allowed to rest, and then re-challenged with the same stimuli. The presence of biologically active IL-1β in cell supernatants was calculated as the ratio between free IL-1β (i.e., the cytokine that is not bound/inhibited by sIL-1R2 and its receptor antagonist IL-1Ra. As expected, we observed that the responsiveness of tissue-like/deactivated macrophages to bacterial stimuli was lower than that of monocytes. After resting and re-stimulation, a memory effect was evident for the production of inflammatory cytokines, whereas production of alarm signals (chemokines was minimally affected. We observed a high variability in the innate memory response among individual donors. This is expected since innate memory largely depends on the previous history of exposure or infections, which is different in different subjects. Overall, innate memory appeared to limit the amount of active IL-1β produced by macrophages in response to a bacterial challenge, while enhancing the responsiveness of monocytes. The functional re-programming of mononuclear phagocytes through modulation of innate memory may provide innovative approaches in the management

  15. Endomorphins and ohmefentanyl in the inhibition of immunosuppressant function in rat peritoneal macrophages: An experimental in vitro study

    OpenAIRE

    Li, Wei-Yan; Yang, Jian-Jun; Zhu, Si-Hai; Liu, Hong-Jun; Xu, Jian-Guo

    2008-01-01

    Background: The potential immunosuppressant effects of opioids might have clinical implications. The effects of endomorphins (EMs) and ohmefentanyl (OMF) on cultured rat peritoneal macrophages remain unclear.

  16. Low pH Environmental Stress Inhibits LPS and LTA-Stimulated Proinflammatory Cytokine Production in Rat Alveolar Macrophages

    Directory of Open Access Journals (Sweden)

    Stanley F. Fernandez

    2013-01-01

    Full Text Available Gastric aspiration increases the risks for developing secondary bacterial pneumonia. Cytokine elaboration through pathogen recognition receptors (PRRs is an important mechanism in initiating innate immune host response. Effects of low pH stress, a critical component of aspiration pathogenesis, on the PRR pathways were examined, specifically toll-like receptor-2 (TLR2 and TLR4, using isolated rat alveolar macrophages (aMØs. We assessed the ability of aMØs after brief exposure to acidified saline to elaborate proinflammatory cytokines in response to lipopolysaccharide (LPS and lipoteichoic acid (LTA stimulation, known ligands of TLR4 and TLR2, respectively. Low pH stress reduced LPS- and LTA-mediated cytokine release (CINC-1, MIP-2, TNF-, MCP-1, and IFN-. LPS and LTA increased intracellular Ca2+ concentrations while Ca2+ chelation by BAPTA decreased LPS- and LTA-mediated cytokine responses. BAPTA blocked the effects of low pH stress on most of LPS-stimulated cytokines but not of LTA-stimulated responses. In vivo mouse model demonstrates suppressed E. coli and S. pneumoniae clearance following acid aspiration. In conclusion, low pH stress inhibits antibacterial cytokine response of aMØs due to impaired TLR2 (MyD88 pathway and TLR4 signaling (MyD88 and TRIF pathways. The role of Ca2+ in low pH stress-induced signaling is complex but appears to be distinct between LPS- and LTA-mediated responses.

  17. Lanthanum Chloride Inhibiting Expression of Inducible Nitric Oxide Synthase in RAW264.7 Macrophages Induced by Lipopolysaccharide

    Institute of Scientific and Technical Information of China (English)

    Guo Fei; Lou Yuanlei; Wang Yang; Xie An; Li Guohui

    2007-01-01

    Nitric oxide (NO) and its reaction products were key players in the pathophysiology of sepsis and shock. The present study was designed to explore the effects of lanthanum chloride (LaCl3) on inducible nitric oxide synthase (iNOS) expression, at both gene and protein levels, in RAW264.7 macrophages induced by Lipopolysaccharide (LPS). Reverse transcription polymerase chain reaction (RT-PCR), immunofluorescence, and western blot were employed to measure iNOS gene expression, localization, and protein expression respectively. NO production in culture supernatants was detected by the nitrate reductase method. The results showed that LaCl3 significantly attenuated the iNOS gene and protein expression, as well as NO production in RAW264.7cells induced by LPS.

  18. Morin, a Bioflavonoid Suppresses Monosodium Urate Crystal-Induced Inflammatory Immune Response in RAW 264.7 Macrophages through the Inhibition of Inflammatory Mediators, Intracellular ROS Levels and NF-κB Activation.

    Directory of Open Access Journals (Sweden)

    Chitra Dhanasekar

    Full Text Available Our previous studies had reported that morin, a bioflavanoid exhibited potent anti-inflammatory effect against adjuvant-induced arthritic rats. In this current study, we investigated the anti-inflammatory mechanism of morin against monosodium urate crystal (MSU-induced inflammation in RAW 264.7 macrophage cells, an in vitro model for acute gouty arthritis. For comparison purpose, colchicine was used as a reference drug. We have observed that morin (100-300 μM treatment significantly suppressed the levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, MCP-1 and VEGF, inflammatory mediators (NO and PEG2, and lysosomal enzymes (acid phosphatase, β-galactosidase, N-acetyl glucosamindase and cathepsin D in MSU-crystals stimulated macrophage cells. The mRNA expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, and MCP-1, inflammatory enzymes (iNOS and COX-2, and NF-κBp65 was found downregulated in MSU crystal stimulated macrophage cells by morin treatment, however, the mRNA expression of hypoxanthine phospho ribosyl transferse (HPRT was found to be increased. The flow cytometry analysis revealed that morin treatment decreased intracellular reactive oxygen species levels in MSU crystal stimulated macrophage cells. The western blot analysis clearly showed that morin mainly exerts its anti-inflammatory effects by inhibiting the MSU crystal-induced COX-2 and TNF-α protein expression through the inactivation of NF-κB signaling pathway in RAW 264.7 macrophage cells similar to that of BAY 11-7082 (IκB kinase inhibitor. Our results collectively suggest that morin can be a potential therapeutic agent for inflammatory disorders like acute gouty arthritis.

  19. Stimulation of neoplastic mouse lung cell proliferation by alveolar macrophage-derived, insulin-like growth factor-1 can be blocked by inhibiting MEK and PI3K activation

    Directory of Open Access Journals (Sweden)

    Malkinson Alvin M

    2011-06-01

    -Akt and cyclin D1 levels in neoplastic cells, and the combined inhibition of both MEK and PI3K ablated macrophage-mediated increases in epithelial growth. Conclusions Macrophages produce IGF-1 which directly stimulates neoplastic proliferation through Erk and Akt activation. This observation suggests that combining macrophage ablation therapy with IGF-1R, MEK and/or PI3K inhibition could improve therapeutic response in human lung cancer. Exploring macrophage-based intervention could be a fruitful avenue for future research.

  20. Antibiotic-Mediated Inhibition of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV Infection: A Novel Quinolone Function Which Potentiates the Antiviral Cytokine Response in MARC-145 Cells and Pig Macrophages

    Directory of Open Access Journals (Sweden)

    William A. Cafruny

    2008-01-01

    Full Text Available Porcine reproductive and respiratory syndrome virus (PRRSV is an economically significant agent for which there currently are no effective treatments. Development of antiviral agents for PRRSV as well as many other viruses has been limited by toxicity of known antiviral compounds. In contrast, antibiotics for non-virus microbial infections have been widely useful, in part because of their acceptable toxicity in animals. We report here the discovery that the quinolonecontaining compound Plasmocin™, as well as the quinolones nalidixic acid and ciprofloxacin, have potent anti-PRRSV activity in vitro. PRRSV replication was inhibited by these antibiotics in both cultured MARC-145 cells and cultured primary alveolar porcine macrophages (PAMs. Furthermore, sub-optimal concentrations of nalidixic acid synergized with antiviral cytokines (AK-2 or IFN-γ to quantitatively and qualitatively inhibit PRRSV replication in MARC-145 cells or PAMs. The antiviral activity of Plasmocin and nalidixic acid correlated with reduced actin expression in MARC-145 cells. Replication of the related lactate dehydrogenase-elevating virus (LDV was also inhibited in primary mouse macrophages by Plasmocin. These results are significant to the development of antiviral strategies with potentially reduced toxicity, and provide a model system to better understand regulation of arterivirus replication.

  1. Clinically significant CYP2C inhibition by noscapine but not by glucosamine.

    Science.gov (United States)

    Rosenborg, S; Stenberg, M; Otto, S; Ostervall, J; Masquelier, M; Yue, Q-Y; Bertilsson, L; Eliasson, E

    2010-09-01

    Noscapine and glucosamine reportedly interact with warfarin. We investigated the effects of these drugs on various cytochrome P450 (CYP) activity markers. Twelve healthy subjects were phenotyped at baseline and during separate treatments with noscapine and glucosamine. Whereas glucosamine had no significant effect on CYP activity, noscapine caused marked inhibition of CYP2C9 (4.9-fold increase in urinary losartan/E3174 ratio) and CYP2C19 (3.6-fold increase in the plasma omeprazole/5-hydroxyomeprazole ratio). Noscapine-dependent inhibition of CYP2C9 may explain the interaction with warfarin.

  2. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  3. Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation.

    Science.gov (United States)

    Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

    2015-12-01

    Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

  4. IFN-γ promotes muscle damage in the mdx mouse model of Duchenne muscular dystrophy by suppressing M2 macrophage activation and inhibiting muscle cell proliferation.

    Science.gov (United States)

    Villalta, S Armando; Deng, Bo; Rinaldi, Chiara; Wehling-Henricks, Michelle; Tidball, James G

    2011-11-15

    Duchenne muscular dystrophy is a degenerative disorder that leads to death by the third decade of life. Previous investigations have shown that macrophages that invade dystrophic muscle are a heterogeneous population consisting of M1 and M2 macrophages that promote injury and repair, respectively. In the present investigation, we tested whether IFN-γ worsens the severity of mdx dystrophy by activating macrophages to a cytolytic M1 phenotype and by suppressing the activation of proregenerative macrophages to an M2 phenotype. IFN-γ is a strong inducer of the M1 phenotype and is elevated in mdx dystrophy. Contrary to our expectations, null mutation of IFN-γ caused no reduction of cytotoxicity of macrophages isolated from mdx muscle and did not reduce muscle fiber damage in vivo or improve gross motor function of mdx mice at the early, acute peak of pathology. In contrast, ablation of IFN-γ reduced muscle damage in vivo during the regenerative stage of the disease and increased activation of the M2 phenotype and improved motor function of mdx mice at that later stage of the disease. IFN-γ also inhibited muscle cell proliferation and differentiation in vitro, and IFN-γ mutation increased MyoD expression in mdx muscle in vivo, showing that IFN-γ can have direct effects on muscle cells that could impair repair. Taken together, the findings show that suppression of IFN-γ signaling in muscular dystrophy reduces muscle damage and improves motor performance by promoting the M2 macrophage phenotype and by direct actions on muscle cells.

  5. Repression of proinflammatory gene expression by lipid extract of Nostoc commune var sphaeroides Kützing, a blue-green alga, via inhibition of nuclear factor-kappaB in RAW 264.7 macrophages.

    Science.gov (United States)

    Park, Young-Ki; Rasmussen, Heather E; Ehlers, Sarah J; Blobaum, Kara R; Lu, Fan; Schlegal, Vicki L; Carr, Timothy P; Lee, Ji-Young

    2008-02-01

    We investigated whether lipid extract from a blue-green alga, N commune, modulates proinflammatory gene expression in RAW 264.7 macrophages. The cells were incubated with N commune lipid extract (0-100 microg/mL) and subsequently activated by LPS (100 ng/mL). Quantitative real-time PCR analysis showed that mRNA abundance of proinflammatory mediators, including TNF-alpha, COX-2, IL-1beta, IL-6, and iNOS, was significantly reduced by N commune lipid extract in a dose-dependent manner. Secretion of TNF-alpha and IL-1beta into cell culture medium was also significantly decreased by N commune lipid extract. Thin-layer chromatography-densitometry analysis showed that N commune lipid extract contained approximately 15% of fatty acids. To determine whether the inhibition of proinflammatory mediator production by N commune lipid extract is primarily conferred by fatty acids in the lipid extract, macrophages were incubated with 100 microg/mL of N commune lipid extract or 15 microg/mL of a fatty acid mixture, which was formulated to reflect the fatty acid composition of N commune lipid extract. The fatty acid mixture significantly reduced RNA abundance of TNF-alpha and COX-2, but to a lesser extent than did the N commune lipid extract, suggesting the presence of additional bioactive compounds with an antiinflammatory property in the lipid extract. As NF-kappaB is a major regulator for the proinflammatory gene expression, we measured its DNA-binding activity. DNA-binding activity of NF-kappaB was significantly reduced by N commune lipid extract. In conclusion, our study suggests that N commune lipid extract represses the expression of proinflammatory genes in RAW 264.7 macrophages, at least in part, by inhibiting the activation of NF-kappaB pathway.

  6. The Small Tellurium Compound AS101 Ameliorates Rat Crescentic Glomerulonephritis: Association with Inhibition of Macrophage Caspase-1 Activity via Very Late Antigen-4 Inactivation

    Science.gov (United States)

    Hachmo, Yafit; Kalechman, Yona; Skornick, Itai; Gafter, Uzi; Caspi, Rachel R.; Sredni, Benjamin

    2017-01-01

    Crescentic glomerulonephritis (CGN) is the most aggressive form of GN and, if untreated, patients can progress to end-stage renal failure within weeks of presentation. The α4β1 integrin very late antigen-4 (VLA-4) is an adhesion molecule of fundamental importance to the recruitment of leukocytes in inflammation. We addressed the role of VLA-4 in mediating progressive renal injury in a rat model of CGN using a small tellurium compound. AS101 [ammonium trichloro(dioxoethylene-o,o′)tellurate]. This compound has been previously shown to uniquely inhibit VLA-4 activity by redox inactivation of adjacent thiols in the exofacial domain of VLA-4. The study shows that administration of AS101 either before or after glomerular basement membrane anti-serum injection ameliorates crescent formation or preserves renal function. This was associated with profound inhibition of critical inflammatory mediators, accompanied by decreased glomerular infiltration of macrophages. Mechanistic studies demonstrated vla-4 inactivation on glomerular macrophages both in vitro and in vivo as well as inhibition of caspase-1 activity. Importantly, this cysteine protease activity modification was dependent on VLA-4 inactivation and was associated with the anti-inflammatory activity of AS101. We propose that inactivation of macrophage VLA-4 by AS101 in vivo results in a decrease of inflammatory cytokines and chemokines produced in the glomeruli of diseased rats, resulting in decreased further macrophage recruitment and decreased extracellular matrix expansion. Thus, AS101, which is currently in clinical trials for other indications, might be beneficial for treatment of CGN.

  7. Chrysin, Apigenin and Acacetin Inhibit Tumor Necrosis Factor-Related Apoptosis—Inducing Ligand Receptor-1 (TRAIL-R1 on Activated RAW264.7 Macrophages

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    Monika Warat

    2014-06-01

    Full Text Available Expression level of Tumor Necrosis Factor—related apoptosis—inducing ligand (TRAIL receptors is one of the most important factors of TRAIL-mediated apoptosis in cancer cells. We here report for the first time data concerning TRAIL-R1 and TRAIL-R2 receptor expression on RAW264.7 macrophages. Three substances belonging to flavones: chrysin, apigenin and acacetin which differ from their substituents at the 4' position in the phenyl ring were used in assays because of the variety of biological activities (e.g., anticancer activity of the polyphenol compounds. The expression of TRAIL-R1 and TRAIL-R2 death receptors on non-stimulated and LPS (lipopolysaccharide-stimulated macrophages was determined using flow cytometry. We demonstrate that RAW264.7 macrophages exhibit TRAIL-R1 surface expression and that the tested compounds: chrysin, apigenin and acacetin can inhibit TRAIL-R1 death receptor expression level on macrophages.

  8. Behaviorally inhibited individuals demonstrate significantly enhanced conditioned response acquisition under non-optimal learning conditions.

    Science.gov (United States)

    Holloway, J L; Allen, M T; Myers, C E; Servatius, R J

    2014-03-15

    Behavioral inhibition (BI) is an anxiety vulnerability factor associated with hypervigilance to novel stimuli, threat, and ambiguous cues. The progression from anxiety risk to a clinical disorder is unknown, although the acquisition of defensive learning and avoidance may be a critical feature. As the expression of avoidance is also central to anxiety development, the present study examined avoidance acquisition as a function of inhibited temperament using classical eyeblink conditioning. Individuals were classified as behaviorally inhibited (BI) or non-inhibited (NI) based on combined scores from the Adult and Retrospective Measures of Behavioural Inhibition (AMBI and RMBI, respectively). Acquisition was assessed using delay, omission, or yoked conditioning schedules of reinforcement. Omission training was identical to delay, except that the emission of an eyeblink conditioned response (CR) resulted in omission of the unconditioned airpuff stimulus (US) on that trial. Each subject in the yoked group was matched on total BI score to a subject in the omission group, and received the same schedule of CS and US delivery, resulting in a partial reinforcement training schedule. Delay conditioning elicited significantly more CRs compared to the omission and yoked contingencies, the latter two of which did not differ from each other. Thus, acquisition of an avoidance response was not apparent. BI individuals demonstrated enhanced acquisition overall, while partial reinforcement training significantly distinguished between BI and NI groups. Enhanced learning in BI may be a function of an increased defensive learning capacity, or sensitivity to uncertainty. Further work examining the influence of BI on learning acquisition is important for understanding individual differences in disorder etiology in anxiety vulnerable cohorts.

  9. Sesamin increases heme oxygenase-1 protein in RAW 264.7 macrophages through inhibiting its ubiquitination process.

    Science.gov (United States)

    Fukunaga, Mizuki; Ohnishi, Masatoshi; Shiratsuchi, Ayano; Kawakami, Takuya; Takahashi, Madoka; Motomura, Misato; Egusa, Kyohei; Urasaki, Tomoka; Inoue, Atsuko

    2014-10-15

    Sesamin is a major component in lignans of sesame seed oil, known to possess potent anti-oxidative capacity. In this study, the variation of heme oxygenase (HO)-1, a kind of anti-oxidative enzyme, by sesamin in murine macrophage cell line RAW 264.7 cells was investigated. Lipopolysaccharide (LPS; 10μg/ml) exposure tended to increase HO-1 protein expression. Co-treatment with 100μM sesamin for 12h up-regulated the HO-1 protein level increased by LPS; however, HO-1 mRNA was unaffected. Sesamin delayed the reversal, by the protein synthesis inhibitor cycloheximide (1μM), of the LPS-induced increase of HO-1 protein level. Meanwhile, sesamin suppressed LPS-induced expression of inducible nitric oxide (NO) synthase (iNOS) protein and associated NO release. LPS-induced increase of iNOS protein expression was also reversed by cycloheximide, which was not affected by sesamin, unlike HO-1. To clarify the mechanisms that underlie the up-regulation of HO-1 protein level by sesamin, the human embryonic kidney (HEK) 293T cell line transfected with Flag-tagged HO-1 was used. A proteasome inhibitor, MG-132 (10μM), stabilized HO-1 protein in HEK 293T cells. Co-treatment with sesamin decreased ubiquitinated HO-1 protein accumulation by MG-132. However, sesamin did not affect the proteasome activity. These findings suggest that sesamin disturbs the degradation of HO-1 protein through inhibiting its ubiquitination, resulting in HO-1 protein up-regulation.

  10. Ethanol extract of propolis protects macrophages from oxidized low density lipoprotein-induced apoptosis by inhibiting CD36 expression and endoplasmic reticulum stress-C/EBP homologous protein pathway.

    Science.gov (United States)

    Tian, Hua; Sun, Hong-Wei; Zhang, Jia-Jun; Zhang, Xiao-Wei; Zhao, Li; Guo, Shou-Dong; Li, Yan-Yan; Jiao, Peng; Wang, Hao; Qin, Shu-Cun; Yao, Shu-Tong

    2015-07-14

    Ethanol extract of propolis (EEP), rich in flavones, has been known for various biological activities including antioxidant, antiinflammatory and antibiotic activities. Our previous studies have shown that EEP protects endothelial cells from oxidized low-density lipoprotein (ox-LDL)-induced apoptosis and inhibits atherosclerotic lesion development. In this present study, we explored the protective effect of EEP on ox-LDL-induced cytotoxicity in macrophages and specifically the endoplasmic reticulum (ER) stress-C/EBP homologous protein (CHOP) pathway-mediated apoptosis. EEP was prepared and the total flavonoids content of EEP was determined by the colorimetric method of Chinese Standard (GB/T 20574-2006). The effects of EEP on lipid accumulation, cytotoxicity and apoptosis in RAW264.7 cells induced by ox-LDL or tunicamycin (TM, an ER stress inducer) were assayed using oil red O staining, MTT assay, flow cytometric analysis and so on. Immunofluorescence, Western blot and real time-PCR analysis were then used to further investigate the molecular mechanisms by which EEP protects macrophages from ox-LDL-induced apoptosis. 4-phenylbutyric acid (PBA), an ER stress inhibitor, was used as a positive control. EEP (7.5, 15 and 30 mg/L) not only attenuated ox-LDL-induced lipid accumulation in RAW264.7 macrophages in a dose-dependent manner but also inhibited the decreased cell viability and the increased lactate dehydrogenase (LDH) leakage, caspase-3 activation and apoptosis induced by ox-LDL or tunicamycin (TM, a classical ER stress inducer), which were similar to 4-phenylbutyric acid (PBA, an inhibitor of ER stress) treatment. In addition, like PBA, EEP significantly suppressed the ox-LDL- or TM-induced activation of ER stress signaling pathway including the phosphorylation of double-stranded RNA-activated protein kinase-like ER kinase (PERK) and eukaryotic translation initiation factor 2α (eIF2α) as well as upregulation of glucose regulated protein 78 (GRP78) and the pro

  11. Phellinus linteus inhibits inflammatory mediators by suppressing redox-based NF-kappaB and MAPKs activation in lipopolysaccharide-induced RAW 264.7 macrophage.

    Science.gov (United States)

    Kim, Ho Gyoung; Yoon, Deok Hyo; Lee, Won Ho; Han, Sang Kuk; Shrestha, Bhushan; Kim, Chun Hoi; Lim, Mi Hee; Chang, Woochul; Lim, Soyeon; Choi, Sunga; Song, Won O; Sung, Jae Mo; Hwang, Ki Chul; Kim, Tae Woong

    2007-12-03

    The mushroom Phellinus linteus has been known to exhibit potent biological activity. In contrast to the immuno-potentiating properties of Phellinus linteus, the anti-inflammatory properties of Phellinus linteus have rarely been investigated. Recently, ethanol extract and n-BuOH fractions from Phellinus linteus were deemed most effective in anti-inflammatory activity in RAW 264.7 macrophages. The regulatory mechanisms of Phellinus linteus butanol fractions (PLBF) on the pharmacological and biochemical actions of macrophages involved in inflammation have not been clearly defined yet. In the present study, we tested the role of PLBF on anti-inflammation patterns in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. To investigate the mechanism by which PLBF inhibits NO and PGE2 production as well as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, we examined the activation of IkappaB and MAPKs in LPS-activated macrophages. PLBF clearly inhibited nuclear translocation of NF-kappaB p65 subunits, which correlated with PLBF's inhibitory effects on IkappaBalpha phosphorylation and degradation. PLBF also suppressed the activation of mitogen-activated protein (MAP) kinases including p38 and stress-activated protein kinase/c-Jun NH2-terminal kinase (SAPK/JNK). Furthermore, macrophages stimulated with LPS generated ROS via activation of membrane-bound NADPH oxidase, and ROS played an important role in the activation of nuclear factor-kappaB (NF-kappaB) and MAPKs. We demonstrated that PLBF directly blocked intracellular accumulation of reactive oxygen species in RAW 264.7 cells stimulated with LPS much as the NADPH oxidase inhibitors, diphenylene iodonium, and antioxidant pyrrolidine dithiocarbamate did. The suppression of NADPH oxidase also inhibited NO production and iNOS protein expression. Cumulatively, these results suggest that PLBF inhibits the production of NO and PGE2 through the down-regulation of iNOS and COX-2 gene

  12. Effects of formocresol alone vs. formocresol with eugenol on macrophage adhesion to plastic surfaces.

    Science.gov (United States)

    Segura, J J; Jiménez-Rubio, A; Calvo, J R

    1998-01-01

    The purpose of this study was to compare the in-vitro effects of a European-based formocresol formulation that incorporates eugenol with formocresol alone on the adhesion of macrophages to plastic surfaces. Macrophages were obtained from Wistar rats. The adherence capacity of macrophages to a plastic surface was determined. Assays were carried out in Eppendorf tubes incubated for 15 min at 37 degrees C in a humidified atmosphere of 5% CO2. The adherence index was calculated. Results showed that both formocresol/eugenol and formocresol alone significantly decreased the adherence index of macrophages. The formocresol formulation that incorporated eugenol was more potent in inhibiting macrophage adhesion than formocresol alone. Taking into account that adherence to a substrate is the first step in the phagocytic process of macrophages and in antigen presentation, both formocresol formulations could inhibit macrophage function and modulate immune and inflammatory responses in dental pulp and periapical tissues.

  13. Significance of bacterial flora in abdominal irradiation-induced inhibition of lung metastases

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    Matsumoto, T.; Ando, K.; Koike, S.

    1988-06-01

    We have previously reported that abdominal irradiation prior to i.v. injection of syngeneic tumor cells reduced metastases in lung. Our report described an investigation of the significance of intestinal organisms in the radiation effect. We found that eliminating intestinal organisms with antibiotics totally abolished the radiation effect. Monoassociation of germ-free mice revealed that the radiation effect was observable only for Enterobacter cloacae, never for Streptococcus faecium, Bifidobacterium adlesentis, or Escherichia coli. After abdominal irradiation of regular mice, E. cloacae multiplied in cecal contents, adhered to mucous membranes, invaded the cecal wall, and translocated to mesenteric lymph nodes. Intravenous administration of E. cloacae in place of abdominal irradiation inhibited metastases. E. cloacae-monoassociated mice developed fewer metastases than germ-free mice, and the reduction was further enhanced by abdominal irradiation. We concluded that abdominal irradiation caused the invasion of E. cloacae from the mucous membrane of the intestine and inhibited formation of lung metastases.

  14. cAMP elevators inhibit LPS-induced IL-12 p40 expression by interfering with phosphorylation of p38 MAPK in Murine Peritoneal Macrophages

    Institute of Scientific and Technical Information of China (English)

    WEI; GUO; FENG; YI; BING; WANG; JIN; SONG; ZHANG; XING; YU; WANG; CHANG; LIN; LI; ZONG; LIANG; CHANG

    2002-01-01

    cAMP mediated signaling may play a suppressive role in immune response. We previously found thatthe cAMP-elevators (CTx and 8-Br-cAMP) inhibited IL-12, IL-la, IL-6 gene expression, but increasedthe transcriptional levels of IL-10 and IL-1Ra in LPS-treated murine peritoneal macrophages. The presentstudy examined a possible molecular mechanism involved in cAMP elevators-induced inhibition of IL-12 p40expression in response to LPS. Our data demonstrated that cAMP elevators downregulated IL-12 p40 mRNAexpression and IL-12 p70 production in murine peritoneal macrophages. Subsequent studies revealed thatcAMP-elevators blocked phosphorylation of p38 MAPK, but did not affect the activity of NF-κB bindingto IL-12 promoter (-136/-112). This is the first report that cAMP elevators inhibit LPS-induced IL-12production by a mechanism that is associated, at least in part, with p38-dependent inhibition by cAMPsignaling pathways.

  15. Identification of a novel compound that inhibits iNOS and COX-2 expression in LPS-stimulated macrophages from Schisandra chinensis.

    Science.gov (United States)

    Lee, You Jin; Park, Sun Young; Kim, Sun Gun; Park, Da Jung; Kang, Jum Soon; Lee, Sang Joon; Yoon, Sik; Kim, Young Hun; Bae, Yoe-Sik; Choi, Young-Whan

    2010-01-22

    A novel alpha-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. alpha-iso-cubebenolinhibited LPS-induced nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production. Consistent with these findings, alpha-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. alpha-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-kappaB p65 subunit. Furthermore, alpha-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel alpha-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin.

  16. Activation of phosphatase and tensin homolog on chromosome 10 mediates the inhibition of FcgammaR phagocytosis by prostaglandin E2 in alveolar macrophages.

    Science.gov (United States)

    Canetti, Claudio; Serezani, Carlos H; Atrasz, Rachelle G; White, Eric S; Aronoff, David M; Peters-Golden, Marc

    2007-12-15

    PGE2 has important inhibitory effects on the macrophage host defense functions of phagocytosis and killing, yet the molecular mechanisms involved remain to be fully elucidated. PGE2 causes an elevation of cAMP in alveolar macrophages (AMs), which in turn activates the cAMP effector targets, protein kinase A and the exchange protein activated by cAMP (Epac)-1. We now report that FcgammaR-induced PI3K/Akt and ERK-1/2 activation are inhibited by PGE2 in AMs. By specifically inhibiting the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in AMs, we attenuated the inhibitory effects of both PGE2 and a specific Epac-1 agonist (8-pCPT-2'-O-Me-cAMP) on FcgammaR-mediated phagocytosis and Akt/ERK-1/2 activation; PTEN inhibition also decreased PGE2-induced suppression of bacterial killing by AMs. Moreover, PGE2 and the Epac-1 agonist induced an increase in PTEN lipid phosphatase activity, and this was associated with decreased tyrosine phosphorylation on PTEN-a mechanism known to regulate PTEN activity. Using a pharmacological approach, we demonstrated a role for Src homology 2-containing protein tyrosine phosphatase-1 in the PGE2-induced tyrosine dephosphorylation of PTEN. Collectively, these data reveal that PGE2, via Epac-1 activation, enhances SHP-1 activity, resulting in increased PTEN activity. We suggest that this mechanism contributes to the ability of PGE2 to inhibit PI3K-dependent innate immune signaling in primary macrophages.

  17. Inhibition of COX-2-mediated eicosanoid production plays a major role in the anti-inflammatory effects of the endocannabinoid N-docosahexaenoylethanolamine (DHEA) in macrophages

    Science.gov (United States)

    Meijerink, Jocelijn; Poland, Mieke; Balvers, Michiel G J; Plastina, Pierluigi; Lute, Carolien; Dwarkasing, Jvalini; van Norren, Klaske; Witkamp, Renger F

    2015-01-01

    BACKGROUND AND PURPOSE N-docosahexaenoylethanolamine (DHEA) is the ethanolamine conjugate of the long-chain polyunsaturated n-3 fatty acid docosahexaenoic (DHA; 22: 6n-3). Its concentration in animal tissues and human plasma increases when diets rich in fish or krill oil are consumed. DHEA displays anti-inflammatory properties in vitro and was found to be released during an inflammatory response in mice. Here, we further examine possible targets involved in the immune-modulating effects of DHEA. EXPERIMENTAL APPROACH Antagonists for cannabinoid (CB)1 and CB2 receptors and PPARγ were used to explore effects of DHEA on NO release by LPS-stimulated RAW264.7 cells. The possible involvement of CB2 receptors was studied by comparing effects in LPS-stimulated peritoneal macrophages obtained from CB2−/− and CB2+/+ mice. Effects on NF-κB activation were determined using a reporter cell line. To study DHEA effects on COX-2 and lipoxygenase activity, 21 different eicosanoids produced by LPS-stimulated RAW264.7 cells were quantified by LC-MS/MS. Finally, effects on mRNA expression profiles were analysed using gene arrays followed by Ingenuity® Pathways Analysis. KEY RESULTS CB1 and CB2 receptors or PPARs were not involved in the effects of DHEA on NO release. NF-κB and IFN-β, key elements of the myeloid differentiation primary response protein D88 (MyD88)-dependent and MyD88-independent pathways were not decreased. By contrast, DHEA significantly reduced levels of several COX-2-derived eicosanoids. Gene expression analysis provided support for an effect on COX–2-mediated pathways. CONCLUSIONS AND IMPLICATIONS Our findings suggest that the anti-inflammatory effects of DHEA in macrophages predominantly take place via inhibition of eicosanoids produced through COX-2. LINKED ARTICLES This article is part of a themed section on Cannabinoids 2013 published in volume 171 issue 6. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10

  18. Anti-inflammatory effect of Mentha longifolia in lipopolysaccharide-stimulated macrophages: reduction of nitric oxide production through inhibition of inducible nitric oxide synthase.

    Science.gov (United States)

    Karimian, Parastoo; Kavoosi, Gholamreza; Amirghofran, Zahra

    2013-01-01

    Mentha longifolia is an aromatic plant used in flavoring and preserving foods and as an anti-inflammatory folk medicine remedy. The present study assessed the effects of M. longifolia extracts, including essential oil and crude methanol extract and its fractions (ethyl acetate, butanol and hexane), on nitric oxide (NO) production and inducible NO synthase (iNOS) mRNA expression in lipopolysaccharide (LPS)-stimulated J774A.1 cells using real-time polymerase chain reaction (PCR). The cytotoxic effects of the extracts on the cells were examined and non-cytotoxic concentrations (<0.2 mg/ml) were used to examine their effects on NO production and iNOS mRNA expression. Only the hexane fraction that contained high levels of phenolic and flavonoid compounds at concentrations from 0.05-0.20 mg/ml significantly reduced NO production in LPS-stimulated cells (p < 0.001). Real-time PCR analysis indicated the ability of this fraction at the same concentrations to significantly decrease iNOS as well as TNFα mRNA expression in the cells (p < 0.001). All extracts were able to scavenge NO radicals in a concentration-dependent manner. At concentrations greater than 0.2 mg/ml, total radicals were 100% scavenged. In conclusion, M. longifolia possibly reduces NO secretion in macrophages by scavenging NO and inhibiting iNOS mRNA expression, and also decreases TNFα pro-inflammatory cytokine expression, thus showing its usefulness in the inflammatory disease process.

  19. Anti-inflammatory effects of flavonoids: genistein, kaempferol, quercetin, and daidzein inhibit STAT-1 and NF-kappaB activations, whereas flavone, isorhamnetin, naringenin, and pelargonidin inhibit only NF-kappaB activation along with their inhibitory effect on iNOS expression and NO production in activated macrophages.

    Science.gov (United States)

    Hämäläinen, Mari; Nieminen, Riina; Vuorela, Pia; Heinonen, Marina; Moilanen, Eeva

    2007-01-01

    In inflammation, bacterial products and proinflammatory cytokines induce the formation of large amounts of nitric oxide (NO) by inducible nitric oxide synthase (iNOS), and compounds that inhibit NO production have anti-inflammatory effects. In the present study, we systematically investigated the effects of 36 naturally occurring flavonoids and related compounds on NO production in macrophages exposed to an inflammatory stimulus (lipopolysaccharide, LPS), and evaluated the mechanisms of action of the effective compounds. Flavone, the isoflavones daidzein and genistein, the flavonols isorhamnetin, kaempferol and quercetin, the flavanone naringenin, and the anthocyanin pelargonidin inhibited iNOS protein and mRNA expression and also NO production in a dose-dependent manner. All eight active compounds inhibited the activation of nuclear factor-kappaB (NF-kappaB), which is a significant transcription factor for iNOS. Genistein, kaempferol, quercetin, and daidzein also inhibited the activation of the signal transducer and activator of transcription 1 (STAT-1), another important transcription factor for iNOS. The present study characterises the effects and mechanisms of naturally occurring phenolic compounds on iNOS expression and NO production in activated macrophages. The results partially explain the pharmacological efficacy of flavonoids as anti-inflammatory compounds.

  20. Inhibition of IkappaB kinase and IkappaB phosphorylation by 15-deoxy-Delta(12,14)-prostaglandin J(2) in activated murine macrophages.

    Science.gov (United States)

    Castrillo, A; Díaz-Guerra, M J; Hortelano, S; Martín-Sanz, P; Boscá, L

    2000-03-01

    Activation of the macrophage cell line RAW 264.7 with lipopolysaccharide (LPS) and gamma interferon (IFN-gamma) induces the expression of gene products involved in host defense, among them type 2 nitric oxide synthase. Treatment of cells with 15-deoxy-Delta(12,14)-prostaglandin J(2) (15dPGJ(2)) inhibited the LPS- and IFN-gamma-dependent synthesis of NO, a process that was not antagonized by similar concentrations of prostaglandin J(2), prostaglandin E(2), or rosiglitazone, a peroxisomal proliferator-activated receptor gamma ligand. Incubation of activated macrophages with 15dPGJ(2) inhibited the degradation of IkappaBalpha and IkappaBbeta and increased their levels in the nuclei. NF-kappaB activity, as well as the transcription of NF-kappaB-dependent genes, such as those encoding type 2 nitric oxide synthase and cyclooxygenase 2, was impaired under these conditions. Analysis of the steps leading to IkappaB phosphorylation showed an inhibition of IkappaB kinase by 15dPGJ(2) in cells treated with LPS and IFN-gamma, resulting in an impaired phosphorylation of IkappaBalpha, at least in the serine 32 residue required for targeting and degradation of this protein. Incubation of partially purified activated IkappaB kinase with 2 microM 15dPGJ(2) reduced by 83% the phosphorylation in serine 32 of IkappaBalpha, suggesting that this prostaglandin exerts direct inhibitory effects on the activity of the IkappaB kinase complex. These results show rapid actions of 15dPGJ(2), independent of peroxisomal proliferator receptor gamma activation, in macrophages challenged with low doses of LPS and IFN-gamma.

  1. Recombinant Lipoprotein Rv1016c Derived from Mycobacterium tuberculosis Is a TLR-2 Ligand that Induces Macrophages Apoptosis and Inhibits MHC II Antigen Processing.

    Science.gov (United States)

    Su, Haibo; Zhu, Shenglin; Zhu, Lin; Huang, Wei; Wang, Honghai; Zhang, Zhi; Xu, Ying

    2016-01-01

    TLR2-dependent cellular signaling in Mycobacterium tuberculosis-infected macrophages causes apoptosis and inhibits class II major histocompatibility complex (MHC-II) molecules antigen processing, leading to evasion of surveillance. Mycobacterium tuberculosis (MTB) lipoproteins are an important class of Toll-like receptor (TLR) ligand, and identified as specific components that mediate these effects. In this study, we identified and characterized MTB lipoprotein Rv1016c (lpqT) as a cell wall associated-protein that was exposed on the cell surface and enhanced the survival of recombinants M. smegmatis_Rv1016c under stress conditions. We found that Rv1016c lipoprotein was a novel TLR2 ligand and able to induce macrophage apoptosis in a both dose- and time-dependent manner. Additionally, apoptosis induced by Rv1016c was reserved in THP-1 cells blocked with anti-TLR-2 Abs or in TLR2(-/-) mouse macrophages, indicating that Rv1016c-induced apoptosis is dependent on TLR2. Moreover, we demonstrated that Rv1016c lipoprotein inhibited IFN-γ-induced MHC-II expression and processing of soluble antigens in a TLR2 dependent manner. Class II transactivator (CIITA) regulates MHC II expression. In this context, Rv1016c lipoprotein diminished IFN-γ-induced expression of CIITA IV through TLR2 and MAPK Signaling. TLR2-dependent apoptosis and inhibition of MHC-II Ag processing induced by Rv1016c during mycobacteria infection may promote the release of residual bacilli from apoptotic cells and decrease recognition by CD4(+) T cells. These mechanisms may allow intracellular MTB to evade immune surveillance and maintain chronic infection.

  2. The immune modulatory peptide FhHDM-1 secreted by the helminth Fasciola hepatica prevents NLRP3 inflammasome activation by inhibiting endolysosomal acidification in macrophages.

    Science.gov (United States)

    Alvarado, Raquel; To, Joyce; Lund, Maria E; Pinar, Anita; Mansell, Ashley; Robinson, Mark W; O'Brien, Bronwyn A; Dalton, John P; Donnelly, Sheila

    2017-01-01

    The NLRP3 inflammasome is a multimeric protein complex that controls the production of IL-1β, a cytokine that influences the development of both innate and adaptive immune responses. Helminth parasites secrete molecules that interact with innate immune cells, modulating their activity to ultimately determine the phenotype of differentiated T cells, thus creating an immune environment that is conducive to sustaining chronic infection. We show that one of these molecules, FhHDM-1, a cathelicidin-like peptide secreted by the helminth parasite, Fasciola hepatica, inhibits the activation of the NLRP3 inflammasome resulting in reduced secretion of IL-1β by macrophages. FhHDM-1 had no effect on the synthesis of pro-IL-1β. Rather, the inhibitory effect was associated with the capacity of the peptide to prevent acidification of the endolysosome. The activation of cathepsin B protease by lysosomal destabilization was prevented in FhHDM-1-treated macrophages. By contrast, peptide derivatives of FhHDM-1 that did not alter the lysosomal pH did not inhibit secretion of IL-1β. We propose a novel immune modulatory strategy used by F. hepatica, whereby secretion of the FhHDM-1 peptide impairs the activation of NLRP3 by lysosomal cathepsin B protease, which prevents the downstream production of IL-1β and the development of protective T helper 1 type immune responses that are detrimental to parasite survival.-Alvarado, R., To, J., Lund, M. E., Pinar, A., Mansell, A., Robinson, M. W., O'Brien, B. A., Dalton, J. P., Donnelly, S. The immune modulatory peptide FhHDM-1 secreted by the helminth Fasciola hepatica prevents NLRP3 inflammasome activation by inhibiting endolysosomal acidification in macrophages. © FASEB.

  3. Pinelliae Rhizoma, a Toxic Chinese Herb, Can Significantly Inhibit CYP3A Activity in Rats

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    Jinjun Wu

    2015-01-01

    Full Text Available Raw Pinelliae Rhizoma (RPR is a representative toxic herb that is widely used for eliminating phlegm or treating cough and vomiting. Given its irritant toxicity, its processed products, including Pinelliae Rhizoma Praeparatum (PRP and Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine (PRPZA, are more commonly applied and administered concomitantly with other chemical drugs, such as cough medications. This study aimed to investigate the effects of RPR, PRP, and PRPZA on CYP3A activity. Testosterone (Tes and buspirone (BP were used as specific probe substrates ex vivo and in vivo, respectively. CYP3A activity was determined by the metabolite formation ratios from the substrates. Ex vivo results show that the metabolite formation ratios from Tes significantly decreased, indicating that RPR, PRP, and PRPZA could inhibit CYP3A activity in rats. CYP3A protein and mRNA levels were determined to explore the underlying mechanism. These levels showed marked and consistent down-regulation with CYP3A activity. A significant decrease in metabolite formation ratios from BP was also found in PRPZA group in vivo, implying that PRPZA could inhibit CYP3A activity. Conclusively, co-administration of PR with other CYP3A-metabolizing drugs may cause drug–drug interactions. Clinical use of PR-related formulae should be monitored carefully to avoid adverse interactions.

  4. Inhibition of class IIb histone deacetylase significantly improves cloning efficiency in mice.

    Science.gov (United States)

    Ono, Tetsuo; Li, Chong; Mizutani, Eiji; Terashita, Yukari; Yamagata, Kazuo; Wakayama, Teruhiko

    2010-12-01

    Since the first mouse clone was produced by somatic cell nuclear transfer, the success rate of cloning in mice has been extremely low. Some histone deacetylase inhibitors, such as trichostatin A and scriptaid, have improved the full-term development of mouse clones significantly, but the mechanisms allowing for this are unclear. Here, we found that two other specific inhibitors, suberoylanilide hydroxamic acid and oxamflatin, could also reduce the rate of apoptosis in blastocysts, improve the full-term development of cloned mice, and increase establishment of nuclear transfer-generated embryonic stem cell lines significantly without leading to obvious abnormalities. However, another inhibitor, valproic acid, could not improve cloning efficiency. Suberoylanilide hydroxamic acid, oxamflatin, trichostatin A, and scriptaid are inhibitors for classes I and IIa/b histone deacetylase, whereas valproic acid is an inhibitor for classes I and IIa, suggesting that inhibiting class IIb histone deacetylase is an important step for reprogramming mouse cloning efficiency.

  5. Arborvitae (Thuja plicata essential oil significantly inhibited critical inflammation- and tissue remodeling-related proteins and genes in human dermal fibroblasts

    Directory of Open Access Journals (Sweden)

    Xuesheng Han

    2017-06-01

    Full Text Available Arborvitae (Thuja plicata essential oil (AEO is becoming increasingly popular in skincare, although its biological activity in human skin cells has not been investigated. Therefore, we sought to study AEO's effect on 17 important protein biomarkers that are closely related to inflammation and tissue remodeling by using a pre-inflamed human dermal fibroblast culture model. AEO significantly inhibited the expression of vascular cell adhesion molecule 1 (VCAM-1, intracellular cell adhesion molecule 1 (ICAM-1, interferon gamma-induced protein 10 (IP-10, interferon-inducible T-cell chemoattractant (I-TAC, monokine induced by interferon gamma (MIG, and macrophage colony-stimulating factor (M-CSF. It also showed significant antiproliferative activity and robustly inhibited collagen-I, collagen-III, plasminogen activator inhibitor-1 (PAI-1, and tissue inhibitor of metalloproteinase 1 and 2 (TIMP-1 and TIMP-2. The inhibitory effect of AEO on increased production of these protein biomarkers suggests it has anti-inflammatory property. We then studied the effect of AEO on the genome-wide expression of 21,224 genes in the same cell culture. AEO significantly and diversely modulated global gene expression. Ingenuity pathway analysis (IPA showed that AEO robustly affected numerous critical genes and signaling pathways closely involved in inflammatory and tissue remodeling processes. The findings of this study provide the first evidence of the biological activity and beneficial action of AEO in human skin cells.

  6. Macrophage Inflammatory Protein 1α Inhibits Postentry Steps of Human Immunodeficiency Virus Type 1 Infection via Suppression of Intracellular Cyclic AMP

    OpenAIRE

    2005-01-01

    Primary isolates of human immunodeficiency virus type 1 (HIV-1) predominantly use chemokine receptor CCR5 to enter target cells. The natural ligands of CCR5, the β-chemokines macrophage inflammatory protein 1α (MIP-1α), MIP-1β, and RANTES, interfere with HIV-1 binding to CCR5 receptors and decrease the amount of virions entering cells. Although the inhibition of HIV-1 entry by β-chemokines is well documented, their effects on postentry steps of the viral life cycle and on host cell components...

  7. Pharmacological kynurenine 3-monooxygenase enzyme inhibition significantly reduces neuropathic pain in a rat model.

    Science.gov (United States)

    Rojewska, Ewelina; Piotrowska, Anna; Makuch, Wioletta; Przewlocka, Barbara; Mika, Joanna

    2016-03-01

    Recent studies have highlighted the involvement of the kynurenine pathway in the pathology of neurodegenerative diseases, but the role of this system in neuropathic pain requires further extensive research. Therefore, the aim of our study was to examine the role of kynurenine 3-monooxygenase (Kmo), an enzyme that is important in this pathway, in a rat model of neuropathy after chronic constriction injury (CCI) to the sciatic nerve. For the first time, we demonstrated that the injury-induced increase in the Kmo mRNA levels in the spinal cord and the dorsal root ganglia (DRG) was reduced by chronic administration of the microglial inhibitor minocycline and that this effect paralleled a decrease in the intensity of neuropathy. Further, minocycline administration alleviated the lipopolysaccharide (LPS)-induced upregulation of Kmo mRNA expression in microglial cell cultures. Moreover, we demonstrated that not only indirect inhibition of Kmo using minocycline but also direct inhibition using Kmo inhibitors (Ro61-6048 and JM6) decreased neuropathic pain intensity on the third and the seventh days after CCI. Chronic Ro61-6048 administration diminished the protein levels of IBA-1, IL-6, IL-1beta and NOS2 in the spinal cord and/or the DRG. Both Kmo inhibitors potentiated the analgesic properties of morphine. In summary, our data suggest that in neuropathic pain model, inhibiting Kmo function significantly reduces pain symptoms and enhances the effectiveness of morphine. The results of our studies show that the kynurenine pathway is an important mediator of neuropathic pain pathology and indicate that Kmo represents a novel pharmacological target for the treatment of neuropathy.

  8. The CO2 inhibition of terrestrial isoprene emission significantly affects future ozone projections

    Directory of Open Access Journals (Sweden)

    J. A. Pyle

    2008-11-01

    Full Text Available Simulations of future tropospheric composition often include substantial increases in biogenic isoprene emissions arising from the Arrhenius-like leaf emission response and warmer surface temperatures, and from enhanced vegetation productivity in response to temperature and atmospheric CO2 concentration. However, a number of recent laboratory and field data have suggested a direct inhibition of leaf isoprene production by increasing atmospheric CO2 concentration, notwithstanding isoprene being produced from precursor molecules that include some of the primary products of carbon assimilation. The cellular mechanism that underlies the decoupling of leaf photosynthesis and isoprene production still awaits a full explanation but accounting for this observation in a dynamic vegetation model that contains a semi-mechanistic treatment of isoprene emissions has been shown to change future global isoprene emission estimates notably. Here we use these estimates in conjunction with a chemistry-climate model to compare the effects of isoprene simulations without and with a direct CO2-inhibition on late 21st century O3 and OH levels. The impact on surface O3 was significant. Including the CO2-inhibition of isoprene resulted in opposing responses in polluted (O3 decreases of up to 10 ppbv vs. less polluted (O3 increases of up to 10 ppbv source regions, due to isoprene nitrate and peroxy acetyl nitrate (PAN chemistry. OH concentration increased with relatively lower future isoprene emissions, decreasing methane lifetime by ~7 months. Our simulations underline the large uncertainties in future chemistry and climate studies due to biogenic emission patterns and emphasize the problems of using globally averaged climate metrics to quantify the atmospheric impact of reactive, heterogeneously distributed substances.

  9. The CO2 inhibition of terrestrial isoprene emission significantly affects future ozone projections

    Science.gov (United States)

    Young, P. J.; Arneth, A.; Schurgers, G.; Zeng, G.; Pyle, J. A.

    2009-04-01

    Simulations of future tropospheric composition often include substantial increases in biogenic isoprene emissions arising from the Arrhenius-like leaf emission response and warmer surface temperatures, and from enhanced vegetation productivity in response to temperature and atmospheric CO2 concentration. However, a number of recent laboratory and field data have suggested a direct inhibition of leaf isoprene production by increasing atmospheric CO2 concentration, notwithstanding isoprene being produced from precursor molecules that include some of the primary products of carbon assimilation. The cellular mechanism that underlies the decoupling of leaf photosynthesis and isoprene production still awaits a full explanation but accounting for this observation in a dynamic vegetation model that contains a semi-mechanistic treatment of isoprene emissions has been shown to change future global isoprene emission estimates notably. Here we use these estimates in conjunction with a chemistry-climate model to compare the effects of isoprene simulations without and with a direct CO2-inhibition on late 21st century O3 and OH levels. The impact on surface O3 was significant. Including the CO2-inhibition of isoprene resulted in opposing responses in polluted (O3 decreases of up to 10 ppbv) vs. less polluted (O3 increases of up to 10 ppbv) source regions, due to isoprene nitrate and peroxy acetyl nitrate (PAN) chemistry. OH concentration increased with relatively lower future isoprene emissions, decreasing methane lifetime by ~7 months (6.6%). Our simulations underline the large uncertainties in future chemistry and climate studies due to biogenic emission patterns and emphasize the problems of using globally averaged climate metrics (such as global radiative forcing) to quantify the atmospheric impact of reactive, heterogeneously distributed substances.

  10. The human fungal pathogen Cryptococcus neoformans escapes macrophages by a phagosome emptying mechanism that is inhibited by Arp2/3 complex-mediated actin polymerisation.

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    Simon A Johnston

    Full Text Available The lysis of infected cells by disease-causing microorganisms is an efficient but risky strategy for disseminated infection, as it exposes the pathogen to the full repertoire of the host's immune system. Cryptococcus neoformans is a widespread fungal pathogen that causes a fatal meningitis in HIV and other immunocompromised patients. Following intracellular growth, cryptococci are able to escape their host cells by a non-lytic expulsive mechanism that may contribute to the invasion of the central nervous system. Non-lytic escape is also exhibited by some bacterial pathogens and is likely to facilitate long-term avoidance of the host immune system during latency. Here we show that phagosomes containing intracellular cryptococci undergo repeated cycles of actin polymerisation. These actin 'flashes' occur in both murine and human macrophages and are dependent on classical WASP-Arp2/3 complex mediated actin filament nucleation. Three dimensional confocal imaging time lapse revealed that such flashes are highly dynamic actin cages that form around the phagosome. Using fluorescent dextran as a phagosome membrane integrity probe, we find that the non-lytic expulsion of Cryptococcus occurs through fusion of the phagosome and plasma membranes and that, prior to expulsion, 95% of phagosomes become permeabilised, an event that is immediately followed by an actin flash. By using pharmacological agents to modulate both actin dynamics and upstream signalling events, we show that flash occurrence is inversely related to cryptococcal expulsion, suggesting that flashes may act to temporarily inhibit expulsion from infected phagocytes. In conclusion, our data reveal the existence of a novel actin-dependent process on phagosomes containing cryptococci that acts as a potential block to expulsion of Cryptococcus and may have significant implications for the dissemination of, and CNS invasion by, this organism.

  11. J774 macrophages secrete antibiotics via organic anion transporters.

    Science.gov (United States)

    Cao, C X; Silverstein, S C; Neu, H C; Steinberg, T H

    1992-02-01

    Mouse macrophages and J774 macrophage-like cells express probenecid-inhibitable organic anion transporters that remove anionic dyes from the cells' cytoplasmic matrix and secrete these dyes into the extracellular medium. The present studies show that these transporters also secrete antibiotics from J774 macrophages. Penicillin G permeates J774 cells poorly, but after it was introduced into the cell cytoplasm, it was secreted in a probenecid-inhibitable fashion. The quinolone norfloxacin enters macrophages readily. Probenecid retarded the secretion of intracellular norfloxacin by J774 cells and enhanced norfloxacin accumulation three- to fourfold. Thus the intracellular accumulation of norfloxacin is regulated in part by organic anion transporters that secrete norfloxacin (and penicillin G) from J774 cells. This transport process may have clinical significance, as fluoroquinolones inhibit growth of intracellular pathogens such as mycobacteria and Brucella organisms in vitro but fail to arrest infections with these organisms in vivo.

  12. Sterile-α- and armadillo motif-containing protein inhibits the TRIF-dependent downregulation of signal regulatory protein α to interfere with intracellular bacterial elimination in Burkholderia pseudomallei-infected mouse macrophages.

    Science.gov (United States)

    Baral, Pankaj; Utaisincharoen, Pongsak

    2013-09-01

    Burkholderia pseudomallei, the causative agent of melioidosis, evades macrophage killing by suppressing the TRIF-dependent pathway, leading to inhibition of inducible nitric oxide synthase (iNOS) expression. We previously demonstrated that virulent wild-type B. pseudomallei inhibits the TRIF-dependent pathway by upregulating sterile-α- and armadillo motif-containing protein (SARM) and by inhibiting downregulation of signal regulatory protein α (SIRPα); both molecules are negative regulators of Toll-like receptor signaling. In contrast, the less virulent lipopolysaccharide (LPS) mutant of B. pseudomallei is unable to exhibit these features and is susceptible to macrophage killing. However, the functional relationship of these two negative regulators in the evasion of macrophage defense has not been elucidated. We demonstrated here that SIRPα downregulation was observed after inhibition of SARM expression by small interfering RNA in wild-type-infected macrophages, indicating that SIRPα downregulation is regulated by SARM. Furthermore, this downregulation requires activation of the TRIF signaling pathway, as we observed abrogation of SIRPα downregulation as well as restricted bacterial growth in LPS mutant-infected TRIF-depleted macrophages. Although inhibition of SARM expression is correlated to SIRPα downregulation and iNOS upregulation in gamma interferon-activated wild-type-infected macrophages, these phenomena appear to bypass the TRIF-dependent pathway. Similar to live bacteria, the wild-type LPS is able to upregulate SARM and to prevent SIRPα downregulation, implying that the LPS of B. pseudomallei may play a crucial role in regulating the expression of these two negative regulators. Altogether, our findings show a previously unrecognized role of B. pseudomallei-induced SARM in inhibiting SIRPα downregulation-mediated iNOS upregulation, facilitating the ability of the bacterium to multiply in macrophages.

  13. Peptide IDR-1002 Inhibits NF-κB Nuclear Translocation by Inhibition of IκBα Degradation and Activates p38/ERK1/2–MSK1-Dependent CREB Phosphorylation in Macrophages Stimulated with Lipopolysaccharide

    Science.gov (United States)

    Huante-Mendoza, Alejandro; Silva-García, Octavio; Oviedo-Boyso, Javier; Hancock, Robert E. W.; Baizabal-Aguirre, Víctor M.

    2016-01-01

    The inflammatory response is a critical molecular defense mechanism of the innate immune system that mediates the elimination of disease-causing bacteria. Repair of the damaged tissue, and the reestablishment of homeostasis, must be accomplished after elimination of the pathogen. The innate defense regulators (IDRs) are short cationic peptides that mimic natural host defense peptides and are effective in eliminating pathogens by enhancing the activity of the immune system while controlling the inflammatory response. Although the role of different IDRs as modulators of inflammation has been reported, there have been only limited studies of the signaling molecules regulated by this type of peptide. The present study investigated the effect of IDR-1002 on nuclear factor κB (NF-κB) and cAMP-response element-binding protein (CREB) transcription factors that are responsible for triggering and controlling inflammation, respectively, in macrophages. We found that TNF-α and COX-2 expression, IκBα phosphorylation, and NF-κB nuclear translocation were strongly inhibited in macrophages pre-incubated with IDR-1002 and then stimulated with lipopolysaccharide (LPS). IDR-1002 also increased CREB phosphorylation at Ser133 via activation of the p38/ERK1/2–MSK1 signaling pathways without detectable expression of the cytokines IL-4, IL-10, and IL-13 involved is suppressing inflammation or alternative activation. Transcriptional activation of NF-κB and CREB is known to require interaction with the transcriptional coactivator CREB-binding protein (CBP). To test for CBP–NF-κB and CBP–CREB complex formation, we performed co-immunoprecipitation assays. These assays showed that IDR-1002 inhibited the interaction between CBP and NF-κB in macrophages stimulated with LPS, which might explain the inhibition of TNF-α and COX-2 expression. Furthermore, the complex between CBP and CREB in macrophages stimulated with IDR-1002 was also inhibited, which might explain why IDR-1002 did

  14. The essential oil isolated from Artemisia capillaris prevents LPS-induced production of NO and PGE(2) by inhibiting MAPK-mediated pathways in RAW 264.7 macrophages.

    Science.gov (United States)

    Cha, Jeong-Dan; Moon, Sang-Eun; Kim, Hye-Young; Lee, Jeong-Chae; Lee, Kyung-Yeol

    2009-01-01

    Artemisia capillaris (A. capillaris) is used in traditional Korean herbal medicine for its believedanti-inflammatory activities. Previous studies have suggested that the essential oil of A. capillaris contains the active components responsible for its pharmacological effect, even though the mechanism for its action is unclear. This study examined the inhibitory effects of the essential oil of A. capillaris on the lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E(2) (PGE(2)). The essential oil significantly inhibited the production of NO in the LPS-stimulated RAW 264.7 macrophages, which was mediated by the down-regulation of inducible NO synthase (iNOS) expression but not by its direct cytotoxic activity. The essential oil also blocked the secretion of PGE(2) and the expression of cyclooxygenase-2 (COX-2) in the LPS-stimulated cells. Western blot analysis showed that the essential oil inhibited the phosphorylation of IkappaB-alpha, nuclear translocation of p65, and subsequent activation of NF-kappaB. In addition, the essential oil suppressed the LPS-stimulated activation of mitogen-activated protein kinases (MAPKs) as well as the AP-1 DNA-binding activity. Moreover, MAPK inhibitors significantly reduced the LPS-induced production of NO and PGE(2). Collectively, we suggest that the oil inhibits the expression and production of inflammatory mediators by blocking the MAPK-mediated pathways and inhibiting the activation of NF-kappaB and AP-1.

  15. The Macrophage Inhibitor CNI-1493 Blocks Metastasis in a Mouse Model of Ewing Sarcoma through Inhibition of Extravasation.

    Directory of Open Access Journals (Sweden)

    Anthony J Hesketh

    Full Text Available Metastatic Ewing Sarcoma carries a poor prognosis, and novel therapeutics to prevent and treat metastatic disease are greatly needed. Recent evidence demonstrates that tumor-associated macrophages in Ewing Sarcoma are associated with more advanced disease. While some macrophage phenotypes (M1 exhibit anti-tumor activity, distinct phenotypes (M2 may contribute to malignant progression and metastasis. In this study, we show that M2 macrophages promote Ewing Sarcoma invasion and extravasation, pointing to a potential target of anti-metastatic therapy. CNI-1493 is a selective inhibitor of macrophage function and has shown to be safe in clinical trials as an anti-inflammatory agent. In a xenograft mouse model of metastatic Ewing Sarcoma, CNI-1493 treatment dramatically reduces metastatic tumor burden. Furthermore, metastases in treated animals have a less invasive morphology. We show in vitro that CNI-1493 decreases M2-stimulated Ewing Sarcoma tumor cell invasion and extravasation, offering a functional mechanism through which CNI-1493 attenuates metastasis. These data indicate that CNI-1493 may be a safe and effective adjuvant agent for the prevention and treatment of metastatic Ewing Sarcoma.

  16. A novel chalcone derivative attenuates the diabetes-induced renal injury via inhibition of high glucose-mediated inflammatory response and macrophage infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Qilu [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Zhao, Leping [Department of Pharmacy, the Affiliated Yueqing Hospital, Wenzhou Medical University, Wenzhou, Zhejiang (China); Wang, Yi; Zhang, Yali [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Zhaoyu [Department of International High School, Shanghai Jiaotong University Nanyang Affiliated (Kunshan) School, Minhang District, Shanghai (China); Pan, Yong; Kanchana, Karvannan; Wang, Jingying; Tong, Chao [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China); Li, Dan, E-mail: yqyyld@163.com [Department of Nephrology, the Affiliated Yueqing Hospital, Wenzhou Medical University, Wenzhou, Zhejiang (China); Liang, Guang, E-mail: wzmcliangguang@163.com [Chemical Biology Research Center, School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang (China)

    2015-01-15

    Inflammation plays a central role in the development and progression of diabetic nephropathy (DN). Researches on novel anti-inflammatory agents may offer new opportunities for the treatment of DN. We previously found a chalcone derivative L6H21 could inhibit LPS-induced cytokine release from macrophages. The aim of this study was to investigate whether L6H21 could ameliorate the high glucose-mediated inflammation in NRK-52E cells and attenuate the inflammation-mediated renal injury. According to the results, L6H21 showed a great inhibitory effect on the expression of pro-inflammatory cytokines, cell adhesion molecules, chemokines, and macrophage adhesion via down-regulation of NF-κB/MAPKs activity in high glucose-stimulated renal NRK-52E cells. Further, in vivo oral administration with L6H21 at a dosage of 20 mg/kg/2 days showed a decreased expression of pro-inflammatory cytokines, cell adhesion molecules, which subsequently contributed to the inhibition on renal macrophage infiltration, the reduction of serum creatinine and BUN levels, and the improvement on the fibrosis and pathological changes in the renal tissues of diabetic mice. These findings provided that chalcone derived L6H21 may be a promising anti-inflammatory agent and have the potential in the therapy of diabetic nephropathy, and importantly, MAPK/NF-κB signaling system may be a novel therapeutic target for human DN in the future. - Highlights: • Inflammation plays a central role in the development of diabetic nephropathy. • Compound L6H21 reduced the high glucose-mediated inflammation in NRK-52E cells. • Compound L6H21 attenuated the inflammation-mediated renal injury. • L6H21 exhibited anti-inflammatory effects via inactivation of NF-κB/MAPKs. • MAPKs/NF-κB may be a novel therapeutic target in diabetic nephropathy treatment.

  17. Role of the Brucella suis Lipopolysaccharide O Antigen in Phagosomal Genesis and in Inhibition of Phagosome-Lysosome Fusion in Murine Macrophages

    Science.gov (United States)

    Porte, Françoise; Naroeni, Aroem; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre

    2003-01-01

    Brucella species are gram-negative, facultative intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment inside professional and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both cell types. However, the molecular mechanisms and the microbial factors involved are poorly understood. Smooth lipopolysaccharide (LPS) of Brucella has been reported to be an important virulence factor, although its precise role in pathogenesis is not yet clear. In this study, we show that the LPS O side chain is involved in inhibition of the early fusion between Brucella suis-containing phagosomes and lysosomes in murine macrophages. In contrast, the phagosomes containing rough mutants, which fail to express the O antigen, rapidly fuse with lysosomes. In addition, we show that rough mutants do not enter host cells by using lipid rafts, contrary to smooth strains. Thus, we propose that the LPS O chain might be a major factor that governs the early behavior of bacteria inside macrophages. PMID:12595466

  18. Acanthopanax koreanum roots inhibit the expression of pro-inflammatory cytokines, inducible nitric oxide synthase, and cyclooxygenase-2 in RAW 264.7 macrophages

    Directory of Open Access Journals (Sweden)

    Eun-Jin Yang

    2016-03-01

    Full Text Available Acanthopanax koreanum is a popular plant found on Jeju Island, Korea and is commonly used to prevent the side effects of consumption of alcoholic beverages. However, this plant has not been properly utilized as a medicinal material. In this study, we investigated the anti-inflammatory effects of the 70% ethanol extract of A. koreanum roots (AKR-E. The results indicated that the AKR-E (200 μg/mL inhibited the lipopolysaccharide (LPS-induced production of nitric oxide (NO and prostaglandin E2 (PGE2 in RAW 264.7 macrophages by 41.2% and 78.9%, respectively. These effects were accompanied by concentration-dependent decreases in the expression levels of inducible NO synthase (iNOS and cyclooxygenase-2 (COX-2 proteins. Additionally, the AKR-E inhibited the expression of pro-inflammatory cytokines, including interleukin (IL-6 (22.7% and IL-1β (74%. These data showed that the AKR-E had protective effects against the induction of LPS-induced inflammation in RAW 264.7 macrophages.

  19. Identification of a novel compound that inhibits iNOS and COX-2 expression in LPS-stimulated macrophages from Schisandra chinensis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, You Jin [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of); Park, Sun Young [Korea BIO-IT Foundry Center, Pusan National University, Busan 609-735 (Korea, Republic of); Kim, Sun Gun; Park, Da Jung; Kang, Jum Soon [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of); Lee, Sang Joon [Department of Microbiology, Pusan National University, Busan 609-735 (Korea, Republic of); Yoon, Sik [Department of Anatomy, School of Medicine, Pusan National University, Yangsan 626-770 (Korea, Republic of); Medical Research Center for Ischemic Tissue Regeneration, School of Medicine, Pusan National University, Yangsan 626-770 (Korea, Republic of); Kim, Young Hun [Korea BIO-IT Foundry Center, Pusan National University, Busan 609-735 (Korea, Republic of); Bae, Yoe-Sik, E-mail: yoesik@dau.ac.kr [Department of Biochemistry, College of Medicine, Dong-A University, Busan 602-714 (Korea, Republic of); Choi, Young-Whan, E-mail: ywchoi@pusan.ac.kr [Department of Horticultural Bioscience, Pusan National University, Miryang 627-706 (Korea, Republic of)

    2010-01-22

    A novel {alpha}-iso-cubebenol, which has anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages, was isolated from the fruits of Schisandra chinensis. {alpha}-iso-cubebenol inhibited LPS-induced nitric oxide (NO) and prostaglandin E{sub 2} (PGE{sub 2}) production. Consistent with these findings, {alpha}-iso-cubebenol also reduced the LPS-induced expression of inducible nitric oxide synthase and cyclooxygenase-2 at the protein and mRNA levels in a concentration-dependent manner. {alpha}-iso-cubebenol also inhibited LPS-induced nuclear translocation of the NF-{kappa}B p65 subunit. Furthermore, {alpha}-iso-cubebenol suppressed the phosphorylation of ERK, JNK, and p38 kinase induced by LPS. Since the novel {alpha}-iso-cubebenol blocked the production of several pro-inflammatory mediators induced by LPS in macrophages, the molecule can be useful material for the development of anti-inflammatory agents against bacterial infections or endotoxin.

  20. 硫氢化钠抑制人巨噬细胞炎性因子的分泌%Sodium hydrosulfide inhibits inflammatory factor secretion by macrophages

    Institute of Scientific and Technical Information of China (English)

    张巧丽; 闫辉; 唐朝枢; 金红芳; 杜军保

    2012-01-01

    /L ox-LDL and 500 μmol/L NaHS. Cell supernatants in all the above groups were collected after induction for 48 h. ELISA was used to examine the content of tumor necrosis factor-a (TNF-a) , interleukin-10 (IL-10) and macrophage migration inhibitory factor (MIF) in cell supernatant. Results Compared to the control group, the content of pro-inflammatory factors-TNF-α and MIF increased significantly (P <0. 05) while the content of anti-inflammatory factor IL-10 decreased significantly in the ox-LDL group (P < 0. 05); compared to the ox-LDL group, the content of TNF-α and MIF decreased greatly(P <0. 05) while the content of IL-10 increased significantly in the ox-LDL + NaHS 100 or 500 μmol/L group (P < 0. 05 ). Conclusions NaHS inhibits the secretion of pro-inflammatory factors-TNF-α and MIF, but promotes the secretion of anti-inflammatory factor-IL-10 while the stimulates of ox-LDL.

  1. Tramadol differentially regulates M1 and M2 macrophages from human umbilical cord blood.

    Science.gov (United States)

    Zhang, Jun; Chen, Liang; Sun, Yunyun; Li, Yuanhai

    2017-03-17

    Tramadol is an analgesic drug and relieves pain through activating μ-opioid receptors and inhibiting serotonin and noradrenaline reuptake. Emerging evidence shows that it also stimulates immune cells, including NK cells, splenocytes, and lymphocytes, and elevates IL-2 production. However, it remains unknown whether and how tramadol directly affects macrophages. To answer these questions, we collected human umbilical cord blood, isolated macrophages, and examined their responses to tramadol. Although tramadol did not alter resting macrophages and the antigen-presenting function in lipopolysaccharide-activated macrophages, it regulated M1 and M2 macrophages, which are, respectively, transformed by IFN-γ and IL-4. Interestingly, tramadol inhibits production and secretion of cytokines in M1 macrophages, but facilitates the production of inflammation-responding molecules, synthesized in M2 macrophages. We also found that STAT6 cascade pathway in M2 macrophages was significantly enhanced by tramadol. Therefore, this study reveals that tramadol regulates inflammation by inhibiting M1 macrophages (killing process), but promoting the function of M2 macrophages (healing process).

  2. Ellagic Acid, a Dietary Polyphenol, Inhibits Tautomerase Activity of Human Macrophage Migration Inhibitory Factor and Its Pro-inflammatory Responses in Human Peripheral Blood Mononuclear Cells.

    Science.gov (United States)

    Sarkar, Souvik; Siddiqui, Asim A; Mazumder, Somnath; De, Rudranil; Saha, Shubhra J; Banerjee, Chinmoy; Iqbal, Mohd S; Adhikari, Susanta; Alam, Athar; Roy, Siddhartha; Bandyopadhyay, Uday

    2015-05-27

    Ellagic acid (EA), a phenolic lactone, inhibited tautomerase activity of human macrophage migration inhibitory factor (MIF) noncompetitively (Ki = 1.97 ± 0.7 μM). The binding of EA to MIF was determined by following the quenching of tryptophan fluorescence. We synthesized several EA derivatives, and their structure-activity relationship studies indicated that the planar conjugated lactone moiety of EA was essential for MIF inhibition. MIF induces nuclear translocation of NF-κB and chemotaxis of peripheral blood mononuclear cells (PBMCs) to promote inflammation. We were interested in evaluating the effect of EA on nuclear translocation of NF-κB and chemotactic activity in human PBMCs in the presence of MIF. The results showed that EA inhibited MIF-induced NF-κB nuclear translocation in PBMCs, as evident from confocal immunofluorescence microscopic data. EA also inhibited MIF-mediated chemotaxis of PBMCs. Thus, we report MIF-inhibitory activity of EA and inhibition of MIF-mediated proinflammatory responses in PBMCs by EA.

  3. Ethylacetate extract from Draconis Resina inhibits LPS-induced inflammatory responses in vascular smooth muscle cells and macrophages via suppression of ROS production.

    Science.gov (United States)

    Heo, Sook-Kyoung; Yi, Hyo-Seung; Yun, Hyun-Jeong; Ko, Chang-Hyun; Choi, Jae-Woo; Park, Sun-Dong

    2010-05-01

    Draconis Resina (DR) is a type of dragon's blood resin obtained from Daemomorops draco BL. (Palmae). DR has long been used as a traditional Korean herbal medicine, and is currently used in traditional clinics to treat wounds, tumors, diarrhea, and rheumatism, insect bites and other conditions. In this study, we evaluated fractionated extracts of DR to determine if they inhibited the production of interleukin-1beta (IL-1beta) and the expression of cyclooxygenase (COX)-2. The results of this analysis revealed that the ethylacetate extract of Draconis Resina (DREA) was more potent than that of other extracts. Moreover, DREA inhibited the production of nitric oxide (NO), reactive oxygen species (ROS), prostaglandin E(2) (PGE(2)), tumor necrosis factor-alpha (TNF-alpha), IL-8 and IL-6 in lipopolysaccharide (LPS)-treated human aortic smooth muscle cells (HASMC) and RAW 264.7 macrophages. Furthermore, treatment with an NADPH oxidase assembly inhibitor, AEBSF, efficiently blocked LPS-induced mitogen-activated protein kinases (MAPKs) activation, as did DREA. These findings indicate that DREA inhibits the production of NO, PGE(2), TNF-alpha, IL-8, and IL-6 by LPS via the inhibition of ROS production, which demonstrates that DREA inhibits LPS-induced inflammatory responses via the suppression of ROS production. Taken together, these results indicate that DREA has the potential for use as an anti-atherosclerosis agent.

  4. Hypoxia-inducible factor-1α and semaphorin4D genes involved with tumor-associated macrophage-induced metastatic behavior and clinical significance in colon cancer.

    Science.gov (United States)

    Mu, Linjun; Wang, Jinshen; Chen, Yuezhi; Li, Leping; Guo, Xiaobo; Zheng, Sheng; Jing, Changqing

    2014-01-01

    Hypoxia promotes tumor angiogenesis and hypoxia-inducible factor-1 alpha (HIF-1α) plays a pivotal role in this process. Recently identified pro-angiogenic factor, semaphorin4D (Sema4D) also promotes angiogenesis and enhances invasive proliferation in some tumors. Furthermore, tumor-associated macrophages (TAMs) can increase the expression of HIF-1α and Sema4D in cancer cells and thus influence tumor growth and progression. The purpose of this study was to evaluate the effect of TAMs on the expression of Sema4D and HIF-1α and the impact of biologic behavior in colon cancer cells. Immunohistochemistry was used to analyze HIF-1α and Sema4D expression in 86 curatively resected colon cancer samples and 52 normal colon tissues samples. The relationship between their expression and clinicopathological factors was analyzed. Furthermore, macrophage-tumor cell interactions, such as metastasis, angiogenesis, were also studied using in vitro co-culture systems. Statistical analysis was performed using SPSS 17.0 software (SPSS Inc., USA). Differences between two groups were analyzed with Student's t test. HIF-1α (58%) and Sema4D (60%) were expressed at a significantly higher level in tumors than in normal tissues (P TNM stages (P 0.05). Sema4D expression was correlated with that of HIF-1α (r = 0.567, P colon cancer cells and subsequently increased their migration and invasion. HIF-1α and Sema4D expression are closely related to lymphatic metastasis, specific histological types and TNM stages in colon cancer. Furthermore, TAMs promote migration and invasion of colon cancer cells and endothelial tube formation, possibly through up-regulation of HIF-1α and Sema4D.

  5. Risperidone significantly inhibits interferon-gamma-induced microglial activation in vitro.

    Science.gov (United States)

    Kato, Takahiro; Monji, Akira; Hashioka, Sadayuki; Kanba, Shigenobu

    2007-05-01

    Microglia has recently been regarded to be a mediator of neuroinflammation via the release of proinflammatory cytokines, nitric oxide (NO) and reactive oxygen species (ROS) in the central nervous system (CNS). Microglia has thus been reported to play an important role in the pathology of neurodegenerative disease, such as Alzheimer's disease (AD) and Parkinson's disease (PD). The pathological mechanisms of schizophrenia remain unclear while some recent neuroimaging studies suggest even schizophrenia may be a kind of neurodegenerative disease. Risperidone has been reported to decrease the reduction of MRI volume during the clinical course of schizophrenia. Many recent studies have demonstrated that immunological mechanisms via such as interferon (IFN)-gamma and cytokines might be relevant to the pathophysiology of schizophrenia. In the present study, we thus investigated the effects of risperidone on the generation of nitric oxide, inducible NO synthase (iNOS) expression and inflammatory cytokines: interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha by IFN-gamma-activated microglia by using Griess assay, Western blotting and ELISA, respectively. In comparison with haloperidol, risperidone significantly inhibited the production of NO and proinflammatory cytokines by activated microglia. The iNOS levels of risperidone-treated cells were much lower than those of the haloperidol-treated cells. Antipsychotics, especially risperidone may have an anti-inflammatory effect via the inhibition of microglial activation, which is not only directly toxic to neurons but also has an inhibitory effect on neurogenesis and oligodendrogenesis, both of which have been reported to play a crucial role in the pathology of schizophrenia.

  6. In vitro exposure to the herbicide atrazine inhibits T cell activation, proliferation, and cytokine production and significantly increases the frequency of Foxp3+ regulatory T cells.

    Science.gov (United States)

    Thueson, Lindsay E; Emmons, Tiffany R; Browning, Dianna L; Kreitinger, Joanna M; Shepherd, David M; Wetzel, Scott A

    2015-02-01

    The herbicide atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino]-s-triazine) is the most common water contaminant in the United States. Atrazine is a phosphodiesterase inhibitor and is classified as an estrogen disrupting compound because it elevates estrogen levels via induction of the enzyme aromatase. Previous studies have shown that atrazine exposure alters the function of innate immune cells such as NK cells, DC, mast cells, and macrophages. In this study we have examined the impact of in vitro atrazine exposure on the activation, proliferation, and effector cytokine production by primary murine CD4(+) T lymphocytes. We found that atrazine exposure significantly inhibited CD4(+) T cell proliferation and accumulation as well as the expression of the activation markers CD25 and CD69 in a dose-dependent manner. Interestingly, the effects were more pronounced in cells from male animals. These effects were partially mimicked by pharmacological reagents that elevate intracellular cAMP levels and addition of exogenous rmIL-2 further inhibited proliferation and CD25 expression. Consistent with these findings, atrazine exposure during T cell activation resulted in a 2- to 5-fold increase in the frequency of Foxp3(+) CD4(+) T cells. © The Author 2014. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. NF-κB/AP-1-Targeted Inhibition of Macrophage-Mediated Inflammatory Responses by Depigmenting Compound AP736 Derived from Natural 1,3-Diphenylpropane Skeleton

    Directory of Open Access Journals (Sweden)

    Van Thai Ha

    2014-01-01

    Full Text Available AP736 was identified as an antimelanogenic drug that can be used for the prevention of melasma, freckles, and dark spots in skin by acting as a suppressor of melanin synthesis and tyrosinase expression. Since macrophage-mediated inflammatory responses are critical for skin health, here we investigated the potential anti-inflammatory activity of AP736. The effects of AP736 on various inflammatory events such as nitric oxide (NO/prostaglandin (PG E2 production, inflammatory gene expression, phagocytic uptake, and morphological changes were examined in RAW264.7 cells. AP736 was found to strongly inhibit the production of both NO and PGE2 in lipopolysaccharide- (LPS- treated RAW264.7 cells. In addition, AP736 strongly inhibited both LPS-induced morphological changes and FITC-dextran-induced phagocytic uptake. Furthermore, AP736 also downregulated the expression of multiple inflammatory genes, such as inducible NO synthase (iNOS, cyclooxygenase- (COX- 2, and interleukin- (IL- 1β in LPS-treated RAW264.7 cells. Transcription factor analysis, including upstream signalling events, revealed that both NF-κB and AP-1 were targeted by AP736 via inhibition of the IKK/IκBα and IRAK1/TAK1 pathways. Therefore, our results strongly suggest that AP736 is a potential anti-inflammatory drug due to its suppression of NF-κB-IKK/IκBα and AP-1-IRAK1/TAK1 signalling, which may make AP736 useful for the treatment of macrophage-mediated skin inflammation.

  8. Thalidomide inhibits alternative activation of macrophages in vivo and in vitro: a potential mechanism of anti-asthmatic effect of thalidomide.

    Directory of Open Access Journals (Sweden)

    Hyun Seung Lee

    Full Text Available Thalidomide is known to have anti-inflammatory and immunomodulatory actions. However, the effect and the anti-asthmatic mechanism of thalidomide in the pathogenesis of asthmatic airways are not fully understood.This study is designed to determine the effect and the potential mechanism of thalidomide in the pathogenesis of asthmatic airways using animal model of allergic asthma.Six-week-old female BALB/C mice were sensitized with alum plus ovalbumin (OVA and were exposed to OVA via intranasal route for 3 days for challenge. Thalidomide 200 mg/kg was given via gavage twice a day from a day before the challenge and airway hyperresponsivenss (AHR, airway inflammatory cells, and cytokines in bronchoalveolar lavage fluids (BALF were evaluated. The expression levels of pro-inflammatory cytokines and other mediators were evaluated using ELISA, real time (RT-qPCR, and flow cytometry. CRL-2456, alveolar macrophage cell line, was used to test the direct effect of thalidomide on the activation of macrophages in vitro.The mice with thalidomide treatment showed significantly reduced levels of allergen-induced BALF and lung inflammation, AHR, and the expression of a number of pro-inflammatory cytokines and mediators including Th2 related, IL-17 cytokines, and altered levels of allergen-specific IgG1/IgG2a. Of interesting note, thalidomide treatment significantly reduced expression levels of allergen- or Th2 cytokine-stimulated alternative activation of macrophages in vivo and in vitro.These studies highlight a potential use of thalidomide in the treatment of allergic diseases including asthma. This study further identified a novel inhibitory effect of thalidomide on alternative activation of macrophages as a potential mechanism of anti-asthmatic effect of thalidomide.

  9. Quince (Cydonia oblonga Miller) peel polyphenols modulate LPS-induced inflammation in human THP-1-derived macrophages through NF-{kappa}B, p38MAPK and Akt inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Essafi-Benkhadir, Khadija [Laboratoire d' epidemiologie Moleculaire et Pathologie Experimentale Appliquee Aux Maladies Infectieuses, Institut Pasteur de Tunis (Tunisia); Refai, Amira [Laboratoire de Recherche sur la Transmission, le Controle et l' immunobiologie des Infections, Institut Pasteur de Tunis (Tunisia); Riahi, Ichrak [Laboratoire d' epidemiologie Moleculaire et Pathologie Experimentale Appliquee Aux Maladies Infectieuses, Institut Pasteur de Tunis (Tunisia); Fattouch, Sami [Laboratory LIP-MB National Institute of Applied Sciences and Technology, Tunis (Tunisia); Karoui, Habib [Laboratoire d' epidemiologie Moleculaire et Pathologie Experimentale Appliquee Aux Maladies Infectieuses, Institut Pasteur de Tunis (Tunisia); Essafi, Makram, E-mail: makram.essafi@pasteur.rns.tn [Laboratoire de Recherche sur la Transmission, le Controle et l' immunobiologie des Infections, Institut Pasteur de Tunis (Tunisia)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Quince peel polyphenols inhibit LPS-induced secretion of TNF-{alpha} and IL-8. Black-Right-Pointing-Pointer Quince peel polyphenols augment LPS-induced secretion of IL-10 and IL-6. Black-Right-Pointing-Pointer Quince peel polyphenols-mediated inhibition of LPS-induced secretion of TNF-{alpha} is partially mediated by IL-6. Black-Right-Pointing-Pointer The anti-inflammatory effects of quince polyphenols pass through NF-{kappa}B, p38MAPK and Akt inhibition. -- Abstract: Chronic inflammation is a hallmark of several pathologies, such as rheumatoid arthritis, gastritis, inflammatory bowel disease, atherosclerosis and cancer. A wide range of anti-inflammatory chemicals have been used to treat such diseases while presenting high toxicity and numerous side effects. Here, we report the anti-inflammatory effect of a non-toxic, cost-effective natural agent, polyphenolic extract from the Tunisian quince Cydonia oblonga Miller. Lipopolysaccharide (LPS) treatment of human THP-1-derived macrophages induced the secretion of high levels of the pro-inflammatory cytokine TNF-{alpha} and the chemokine IL-8, which was inhibited by quince peel polyphenolic extract in a dose-dependent manner. Concomitantly, quince polyphenols enhanced the level of the anti-inflammatory cytokine IL-10 secreted by LPS-treated macrophages. We further demonstrated that the unexpected increase in IL-6 secretion that occurred when quince polyphenols were associated with LPS treatment was partially responsible for the polyphenols-mediated inhibition of TNF-{alpha} secretion. Biochemical analysis showed that quince polyphenols extract inhibited the LPS-mediated activation of three major cellular pro-inflammatory effectors, nuclear factor-kappa B (NF-{kappa}B), p38MAPK and Akt. Overall, our data indicate that quince peel polyphenolic extract induces a potent anti-inflammatory effect that may prove useful for the treatment of inflammatory diseases and that a quince

  10. ORF2 protein of porcine circovirus type 2 promotes phagocytic activity of porcine macrophages by inhibiting proteasomal degradation of complement component 1, q subcomponent binding protein (C1QBP) through physical interaction.

    Science.gov (United States)

    Choi, Chang-Yong; Oh, Hae-Na; Lee, Suk Jun; Chun, Taehoon

    2015-11-01

    Defining how each ORF of porcine circovirus type 2 (PCV2) manipulates the host immune system may be helpful to understand the disease progression of post-weaning multisystemic wasting syndrome. In this study, we demonstrated a direct interaction between the PCV2 ORF2 and complement component 1, q subcomponent binding protein (C1QBP) within the cytoplasm of host macrophages. The physical interaction between PCV2 ORF2 and C1QBP inhibited ubiquitin-mediated proteasomal degradation of C1QBP in macrophages. Increased stability of C1QBP by the interaction with PCV2 ORF2 further enhanced the phagocytic activity of porcine macrophages through the phosphoinositol 3-kinase signalling pathway. This may explain the molecular basis of how PCV2 ORF2 enhances the phagocytic activity of host macrophages.

  11. Apigenin Attenuates Atherogenesis through Inducing Macrophage Apoptosis via Inhibition of AKT Ser473 Phosphorylation and Downregulation of Plasminogen Activator Inhibitor-2

    Science.gov (United States)

    Zeng, Ping; Liu, Bin; Wang, Qun; Fan, Qin; Diao, Jian-Xin; Tang, Jing; Fu, Xiu-Qiong; Sun, Xue-Gang

    2015-01-01

    Macrophage survival is believed to be a contributing factor in the development of early atherosclerotic lesions. Dysregulated apoptosis of macrophages is involved in the inflammatory process of atherogenesis. Apigenin is a flavonoid that possesses various clinically relevant properties such as anti-inflammatory, antiplatelet, and antitumor activities. Here we showed that apigenin attenuated atherogenesis in apoE −/− mice in an in vivo test. In vitro experiments suggested that apigenin induced apoptosis of oxidized low density lipoprotein- (OxLDL-) loaded murine peritoneal macrophages (MPMs). Proteomic analysis showed that apigenin reduced the expression of plasminogen activator inhibitor 2 (PAI-2). PAI-2 has antiapoptotic effects in OxLDL-loaded MPMs. Enhancing PAI-2 expression significantly reduced the proapoptosis effects of apigenin. Molecular docking assay with AutoDock software predicted that residue Ser473 of Akt1 is a potential binding site for apigenin. Lentiviral-mediated overexpression of Akt1 wild type weakened the proapoptosis effect of apigenin in OxLDL-loaded MPMs. Collectively, apigenin executes its anti-atherogenic effects through inducing OxLDL-loaded MPMs apoptosis. The proapoptotic effects of apigenin were at least partly attributed to downregulation of PAI-2 through suppressing phosphorylation of AKT at Ser473. PMID:25960827

  12. Apigenin Attenuates Atherogenesis through Inducing Macrophage Apoptosis via Inhibition of AKT Ser473 Phosphorylation and Downregulation of Plasminogen Activator Inhibitor-2

    Directory of Open Access Journals (Sweden)

    Ping Zeng

    2015-01-01

    Full Text Available Macrophage survival is believed to be a contributing factor in the development of early atherosclerotic lesions. Dysregulated apoptosis of macrophages is involved in the inflammatory process of atherogenesis. Apigenin is a flavonoid that possesses various clinically relevant properties such as anti-inflammatory, antiplatelet, and antitumor activities. Here we showed that apigenin attenuated atherogenesis in apoE-/- mice in an in vivo test. In vitro experiments suggested that apigenin induced apoptosis of oxidized low density lipoprotein- (OxLDL- loaded murine peritoneal macrophages (MPMs. Proteomic analysis showed that apigenin reduced the expression of plasminogen activator inhibitor 2 (PAI-2. PAI-2 has antiapoptotic effects in OxLDL-loaded MPMs. Enhancing PAI-2 expression significantly reduced the proapoptosis effects of apigenin. Molecular docking assay with AutoDock software predicted that residue Ser473 of Akt1 is a potential binding site for apigenin. Lentiviral-mediated overexpression of Akt1 wild type weakened the proapoptosis effect of apigenin in OxLDL-loaded MPMs. Collectively, apigenin executes its anti-atherogenic effects through inducing OxLDL-loaded MPMs apoptosis. The proapoptotic effects of apigenin were at least partly attributed to downregulation of PAI-2 through suppressing phosphorylation of AKT at Ser473.

  13. Apigenin Attenuates Atherogenesis through Inducing Macrophage Apoptosis via Inhibition of AKT Ser473 Phosphorylation and Downregulation of Plasminogen Activator Inhibitor-2.

    Science.gov (United States)

    Zeng, Ping; Liu, Bin; Wang, Qun; Fan, Qin; Diao, Jian-Xin; Tang, Jing; Fu, Xiu-Qiong; Sun, Xue-Gang

    2015-01-01

    Macrophage survival is believed to be a contributing factor in the development of early atherosclerotic lesions. Dysregulated apoptosis of macrophages is involved in the inflammatory process of atherogenesis. Apigenin is a flavonoid that possesses various clinically relevant properties such as anti-inflammatory, antiplatelet, and antitumor activities. Here we showed that apigenin attenuated atherogenesis in apoE (-/-) mice in an in vivo test. In vitro experiments suggested that apigenin induced apoptosis of oxidized low density lipoprotein- (OxLDL-) loaded murine peritoneal macrophages (MPMs). Proteomic analysis showed that apigenin reduced the expression of plasminogen activator inhibitor 2 (PAI-2). PAI-2 has antiapoptotic effects in OxLDL-loaded MPMs. Enhancing PAI-2 expression significantly reduced the proapoptosis effects of apigenin. Molecular docking assay with AutoDock software predicted that residue Ser473 of Akt1 is a potential binding site for apigenin. Lentiviral-mediated overexpression of Akt1 wild type weakened the proapoptosis effect of apigenin in OxLDL-loaded MPMs. Collectively, apigenin executes its anti-atherogenic effects through inducing OxLDL-loaded MPMs apoptosis. The proapoptotic effects of apigenin were at least partly attributed to downregulation of PAI-2 through suppressing phosphorylation of AKT at Ser473.

  14. 6-Gingerol inhibits ROS and iNOS through the suppression of PKC-{alpha} and NF-{kappa}B pathways in lipopolysaccharide-stimulated mouse macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tzung-Yan, E-mail: joyamen@mail.cgu.edu.tw [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Lee, Ko-Chen [School of Traditional Chinese Medicine, Chang Gung University, Taiwan (China); Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan (China); Chen, Shih-Yuan [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Chang, Hen-Hong [Graduate Institute of Traditional Chinese Medicine, Chang Gung University, No. 259, Wen-Hwa 1st Road, Kwei-Shan Tao-Yuan 333, Taiwan (China); Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan (China)

    2009-04-24

    Inflammation is involved in numerous diseases, including chronic inflammatory diseases and the development of cancer. Many plants possess a variety of biological activities, including antifungal, antibacterial and anti-inflammatory activities. However, our understanding of the anti-inflammatory effects of 6-gingerol is very limited. We used lipopolysaccharide (LPS)-stimulated macrophages as a model of inflammation to investigate the anti-inflammatory effects of 6-gingerol, which contains phenolic structure. We found that 6-gingerol exhibited an anti-inflammatory effect. 6-Gingerol could decrease inducible nitric oxide synthase and TNF-{alpha} expression through suppression of I-{kappa}B{alpha} phosphorylation, NF-{kappa}B nuclear activation and PKC-{alpha} translocation, which in turn inhibits Ca{sup 2+} mobilization and disruption of mitochondrial membrane potential in LPS-stimulated macrophages. Here, we demonstrate that 6-gingerol acts as an anti-inflammatory agent by blocking NF-{kappa}B and PKC signaling, and may be developed as a useful agent for the chemoprevention of cancer or inflammatory diseases.

  15. Bauer Ketones 23 and 24 from Echinacea paradoxa var. paradoxa Inhibit Lipopolysaccharide-induced Nitric Oxide, Prostaglandin E2 and Cytokines in RAW 264.7 Mouse Macrophages

    Science.gov (United States)

    Zhang, Xiaozhu; Rizshsky, Ludmila; Hauck, Catherine; Qu, Luping; Widrlechner, Mark P.; Nikolau, Basil J.; Murphy, Patricia A.; Birt, Diane F.

    2011-01-01

    Among the nine Echinacea species, E. purpurea, E. angustifolia and E. pallida, have been widely used to treat the common cold, flu and other infections. In our study, ethanol extracts of these three Echinacea species and E. paradoxa, including its typical variety, E. paradoxa var. paradoxa, were screened in lipopolysaccharide (LPS)-stimulated macrophage cells to assess potential anti-inflammatory activity. Echinacea paradoxa var. paradoxa, rich in polyenes/polyacetylenes, was an especially efficient inhibitor of LPS-induced production of nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) by 46%, 32%, 53% and 26%, respectively, when tested at 20 μg/ml in comparison to DMSO control. By bioactivity-guided fractionation, pentadeca-8Z-ene-11, 13-diyn-2-one (Bauer ketones 23, compound 1) and pentadeca-8Z, 13Z-dien-11-yn-2-one (Bauer ketone 24, compound 2) from E. paradoxa var. paradoxa were found primarily responsible for inhibitory effects on NO and PGE2 production. Moreover, Bauer ketone 24 (compound 2) was the major contributor to inhibition of inflammatory cytokine production in LPS-induced mouse macrophage cells. These results provide a rationale for exploring the medicinal effects of the Bauer ketone-rich taxon, E. paradoxa var. paradoxa, and confirm the anti-inflammatory properties of Bauer ketones 23 and 24. PMID:22133644

  16. The interaction of Acanthamoeba castellanii cysts with macrophages and neutrophils.

    Science.gov (United States)

    Hurt, Michael; Proy, Vincent; Niederkorn, Jerry Y; Alizadeh, Hassan

    2003-06-01

    Acanthamoeba castellanii, a free-living amoeba, causes a sight-threatening form of keratitis. Even after extensive therapies, corneal damage can be severe, often requiring corneal transplantation to restore vision. However, A. castellanii cysts are not eliminated from the conjunctiva and stroma of humans and can excyst, resulting in infection of the corneal transplant. The aim of this study was to determine whether elements of the innate immune apparatus, neutrophils and macrophages, were capable of detecting and eliminating A. castellanii cysts and to examine the mechanism by which they kill the cysts. Results show that neither innate immune cell is attracted chemotactically to intact cysts, yet both were attracted to lysed cysts. Both macrophages and neutrophils were capable of killing significant numbers of cysts, yet neutrophils were 3-fold more efficient than macrophages. Activation of macrophages with lipopolysaccharide and interferon-gamma did not increase their cytolytic ability. Conditioned medium isolated from macrophages did not lyse the cysts; however, prevention of phagocytosis by cytochalasin D inhibited 100% of macrophage-mediated killing of the cysts. Conditioned medium from neutrophils did kill significant numbers of the cysts, and this killing was blocked by quercetin, a potent inhibitor of myeloperoxidase (MPO). These results indicate that neither macrophages nor neutrophils are chemoattracted to intact cysts, yet both are capable of killing the cysts. Macrophages killed the cysts by phagocytosis, whereas neutrophils killed cysts through the secretion of MPO.

  17. Novel interactions between erythroblast macrophage protein and cell migration.

    Science.gov (United States)

    Javan, Gulnaz T; Can, Ismail; Yeboah, Fred; Lee, Youngil; Soni, Shivani

    2016-09-01

    Erythroblast macrophage protein is a novel protein known to mediate attachment of erythroid cells to macrophages to form erythroblastic islands in bone marrow during erythropoiesis. Emp-null macrophages are small with round morphologies, and lack cytoplasmic projections which imply immature structure. The role of Emp in macrophage development and function is not fully elucidated. Macrophages perform varied functions (e.g. homeostasis, erythropoiesis), and are implicated in numerous pathophysiological conditions such as cellular malignancy. The objective of the current study is to investigate the interaction of Emp with cytoskeletal- and cell migration-associated proteins involved in macrophage functions. A short hairpin RNA lentiviral system was use to down-regulate the expression of Emp in macrophage cells. A cell migration assay revealed that the relocation of macrophages was significantly inhibited when Emp expression was decreased. To further analyze changes in gene expression related to cell motility, PCR array was performed by down-regulating Emp expression. The results indicated that expression of mitogen-activated protein kinase 1 and thymoma viral proto-oncogene 1 were significantly higher when Emp was down-regulated. The results implicate Emp in abnormal cell motility, thus, warrants to assess its role in cancer where tumor cell motility is required for invasion and metastasis.

  18. LPS-inducible factor(s) from activated macrophages mediates cytolysis of Naegleria fowleri amoebae

    Energy Technology Data Exchange (ETDEWEB)

    Cleary, S.F.; Marciano-Cabral, F.

    1986-03-01

    Soluble cytolytic factors of macrophage origin have previously been described with respect to their tumoricidal activity. The purpose of this study was to investigate the mechanism and possible factor(s) responsible for cytolysis of the amoeba Naegleria fowleri by activated peritoneal macrophages from B6C3F1 mice. Macrophages or conditioned medium (CM) from macrophage cultures were incubated with /sup 3/H-Uridine labeled amoebae. Percent specific release of label served as an index of cytolysis. Bacille Calmette-Guerin (BCG) and Corynebacterium parvum macrophages demonstrated significant cytolysis of amoebae at 24 h with an effector to target ratio of 10:1. Treatment of macrophages with inhibitors of RNA or protein synthesis blocked amoebicidal activity. Interposition of a 1 ..mu..m pore membrane between macrophages and amoebae inhibited killing. Inhibition in the presence of the membrane was overcome by stimulating the macrophages with LPS. CM from SPS-stimulated, but not unstimulated, cultures of activated macrophages was cytotoxic for amoebae. The activity was heat sensitive and was recovered from ammonium sulfate precipitation of the CM. Results indicate that amoebicidal activity is mediated by a protein(s) of macrophage origin induced by target cell contact or stimulation with LPS.

  19. Administration of PDE4 Inhibitors Suppressed the Pannus-Like Inflammation by Inhibition of Cytokine Production by Macrophages and Synovial Fibroblast Proliferation

    Directory of Open Access Journals (Sweden)

    Ichiro Miki

    2007-09-01

    Full Text Available A marked proliferation of synovial fibroblasts in joints leads to pannus formation in rheumatoid arthritis (RA. Various kinds of cytokines are produced in the pannus. The purpose of this study is to elucidate the effects of phosphodiesterase 4 (PDE4 inhibitors in a new animal model for the evaluation of pannus formation and cytokine production in the pannus. Mice sensitized with methylated bovine serum albumin (mBSA were challenged by subcutaneous implantation of a membrane filter soaked in mBSA solution in the back of the mice. Drugs were orally administered for 10 days. The granuloma formed around the filter was collected on day 11. It was chopped into pieces and cultured in vitro for 24 hr. The cytokines were measured in the supernatants. The type of cytokines produced in the granuloma was quite similar to those produced in pannus in RA. Both PDE4 inhibitors, KF66490 and SB207499, suppressed the production of IL-1β, TNF-α, and IL-12, and the increase in myeloperoxidase activity, a marker enzyme for neutrophils and hydroxyproline content. Compared to leflunomide, PDE4 inhibitors more strongly suppressed IL-12 production and the increase in myeloperoxidase activity. PDE4 inhibitors also inhibited lipopolysaccharide-induced TNF-α and IL-12 production from thioglycolate-induced murine peritoneal macrophages and the proliferation of rat synovial fibroblasts. These results indicate this model makes it easy to evaluate the effect of drugs on various cytokine productions in a granuloma without any purification step and may be a relevant model for evaluating novel antirheumatic drugs on pannus formation in RA. PDE4 inhibitors could have therapeutic effects on pannus formation in RA by inhibition of cytokine production by macrophages and synovial fibroblast proliferation.

  20. The α-cyclodextrin complex of the Moringa isothiocyanate suppresses lipopolysaccharide-induced inflammation in RAW 264.7 macrophage cells through Akt and p38 inhibition.

    Science.gov (United States)

    Giacoppo, Sabrina; Rajan, Thangavelu Soundara; Iori, Renato; Rollin, Patrick; Bramanti, Placido; Mazzon, Emanuela

    2017-03-13

    In the last decades, a growing need to discover new compounds for the prevention and treatment of inflammatory diseases has led researchers to consider drugs derived from natural products as a valid option in the treatment of inflammation-associated disorders. The purpose of the present study was to investigate the anti-inflammatory effects of a new formulation of Moringa oleifera-derived 4-(α-L-rhamnopyranosyloxy)benzyl isothiocyanate as a complex with alpha-cyclodextrin (moringin + α-CD) on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells, a common model used for inflammation studies. In buffered/aqueous solution, the moringin + α-CD complex has enhanced the water solubility and stability of this isothiocyanate by forming a stable inclusion system. Our results showed that moringin + α-CD inhibits the production of inflammatory mediators in LPS-stimulated macrophages by down-regulation of pro-inflammatory cytokines (TNF-α and IL-1β), by preventing IκB-α phosphorylation, translocation of the nuclear factor-κB (NF-κB), and also via the suppression of Akt and p38 phosphorylation. In addition, as a consequence of upstream inhibition of the inflammatory pathway following treatment with moringin + α-CD, the modulation of the oxidative stress (results focused on the expression of iNOS and nitrotyrosine) and apoptotic pathway (Bax and Bcl-2) was demonstrated. Therefore, moringin + α-CD appears to be a new relevant helpful tool to use in clinical practice for inflammation-associated disorders.

  1. [Diagnostic significance of the spinal-brain stem polysynaptic reflex and the period of inhibition].

    Science.gov (United States)

    Ivanichev, G A

    1985-01-01

    Electrical stimulation of the radial nerve associated with voluntary contraction of the shoulder girdle inhibited bioelectrical activity not only in the muscles of the hypothenar but also in the proximal muscles. In resting muscles, such stimulation elicited a reflex response with a large latent period. With weak voluntary tension stimulation elicited a reflex response while in the presence of considerable contraction the reflex response merged with bioelectrical activity, with a clearly demonstrable subsequent period of inhibition. The current viewpoint about the antidromal blockade of the segmental motoneurons is debated. It is suggested that the polysynaptic reflex and the inhibition period are connected with the same level of realization -- the oral portions of the brain stem.

  2. Tumoricidal activation of murine resident peritoneal macrophages on pancreatic carcinoma by interleukin-2 and monoclonal antibodies

    Institute of Scientific and Technical Information of China (English)

    Qi Kui Chen; Shi Zhen Yuan; Zhi Yong Zeng; Zhi Qing Huang

    2000-01-01

    @@INTRODUCTION Macrophages play an important role in tumor lysis and growth inhibition. They can be activated to a tumoricidal state by a variety of agents such as IFNr, TNFa or IL2. The killing machanisms of activated macrophages have been extensively investigated[1,2]. Recently, it has been proved that antibody dependent cellular cytotoxicity (ADCC) is one of the potent arms to lyse tumor cells resistant to cytotoxic macrophages,and that the antitumorous effect of a macrophage activator is significantly augmented by the combined use of mAbs capable of inducing ADCC to tumor cells[3].

  3. Th1-like human T-cell clones recognizing Leishmania gp63 inhibit Leishmania major in human macrophages

    DEFF Research Database (Denmark)

    Kemp, M; Hey, A S; Bendtzen, K

    1994-01-01

    The major surface protease of Leishmania major, gp63, has been suggested as a vaccine candidate for cutaneous leishmaniasis. In this study gp63 was purified from L. major promastigotes. A panel of human T-cell clones recognizing this protein were generated from individuals who had previously had...... self-healing cutaneous leishmaniasis. The T-cell clones expressed CD4, and the alpha chain of the T-cell antigen receptor. GP63 reactive T-cell clones activated by antigen or by immobilized anti-CD3 antibody released relative large amounts of interferon-gamma and no or little interleukin-4, thereby...... resembling Th1 cells. Autologous mononuclear cells and Epstein-Barr virus-transformed B cell lines were equally efficient in presenting the antigen to the T cells. The gp63 reactive T cells induced resistance to infection in cultured human macrophages by L. major. The data confirm that human CD4+ T cells...

  4. Role of Toll-like receptor 4 expression inhibition in the transformation of macrophage polarity%抑制 Toll样受体4表达对巨噬细胞极性转化的影响

    Institute of Scientific and Technical Information of China (English)

    翟振丽; 申炜; 马维红; 焦清海

    2015-01-01

    Objective To explore the role of Toll-like receptor 4 in the transformation of the bone marrow-derived macrophage polarity through observation on the effects of CLI-095 on phenotype of macrophages.Methods Our research subjects were the cultured mouse marrow-derived macrophages, and were randomly divided into three groups:the control group ( marrow-derived macrophages cul-tured for 48 h without any drug treatment), the model group (marrow-derived macrophages cultured routine for 24 h, then, addition of 100 U/mlγinterferon and 5 ng/ml lipopolysaccharide into the culture medium and cultured for another 24 h) and the treatment group( first in-cubated in 1 μg/ml CLI-095 for 24 h, then, after change of the fluid, addition of 100 U/mlγinterferon and 5 ng/ml lipopolysaccharide into the culture medium and cultured for another 24 h) .Real-time quantitative PCR was used to detect the mRNA expression of TLR4. The expression of membrane molecules CD16/32, CD206 was detected by using fluorescence activated cell sorting (FACS), and enzyme linked immunosorbent assay (ELISA) was used to detect the secretion of interleukin-10 (IL-10) and IL-12.Results As compared with those of the control group, the expression levels of CD16/32 and IL-12 in the model group were increased significantly, and the level of CD206 was decreased markedly, which was in conformity with the features of macrophages.When compared with those of the model group, the level of TLR4 mRNA was decreased.This indicated that the expression level of TLR4 was inhibited, the levels of CD16/32 and IL-12 were decreased and the levels of CD206 and IL-10 were increased with statistical significance and they were also in conformity with the features of macrophages.Conclusion TLR4 seemed to play an important role in the modulation of macrophage polarity.The inhibited expression level of TLR4 could promote inflammatory macrophages towards an anti-inflammatory M2 phenotype.%目的:通过观察CLI-095对巨噬细胞表

  5. PENGHAMBATAN OKSIDASI LDL DAN AKUMULASI KOLESTEROL PADA MAKROFAG OLEH EKSTRAK TEMULAWAK (Curcuma xanthorriza Roxb [The Inhibition of Low Density Lipoprotein Oxidation and Cholesterol Accumulation on the Macrophage by Temulawak Extract

    Directory of Open Access Journals (Sweden)

    Aisyah Tri Septiana1

    2006-12-01

    Full Text Available Coronary heart disease is caused among others by atherosclerosis, which is the result of oxidized low density lipoprotein (LDL and cholesterol accumulation on macrophage, and which is inhibited by temulawak (Curcuma xanthorriza Roxb extract. The objective of this study was to find out the kinds and consentration of temulawak extract which could inhibit LDL oxidation, and to find out the effect of temulawak extract on the accumulation of cholesterol on macrophage. Temulawak was extracted by water, ethanol, aceton and dichlorometane. Inhibition of LDL oxidation was found out by measuring the level of malonaldehyde content of oxidized LDL-CuSO4 which was supplemented with water extract, ethanol extract, aceton extract and dichlorometane extract. of temulawak at concentrations of 43 g, 430 g, and 4300 g per ml of LDL. The percentage of malonaldehyde reduction due to supplementation with water extract, ethanol extract, acetone extract and dichloromethane extract was 44.27; 47.68; 51.83 and 61.2 respectively. The inhibition of LDL oxidation by temulawak extract depends on its concentration. The percentage of malonaldehyde reduction due to supplementation with temulawak extract of 43 µg, 430 µg, and 4300 µg per ml of LDL was 43.63; 56.72; and 53.89.. Concentration of temulawak extract resulting in the highest inhibition of LDL oxidation was 430 µg/ml LDL. Temulawak extract tends to inhibit cholesterol accumulation on macrophage. There is a relationship between the inhibition of cholesterol accumulation on the macrophage and the inhibition of LDL oxidation by temulawak extract

  6. Ethanol inhibits LPS-induced signaling and modulates cytokine production in peritoneal macrophages in vivo in a model for binge drinking

    Directory of Open Access Journals (Sweden)

    Pruett Stephen B

    2009-09-01

    Full Text Available Abstract Background Previous reports indicate that ethanol, in a binge drinking model in mice, inhibits the production of pro-inflammatory cytokines in vivo. However, the inhibition of signaling through TLR4 has not been investigated in this experimental model in vivo. Considering evidence that signaling can be very different in vitro and in vivo, the present study was conducted to determine if effects of ethanol on TLR4 signaling reported for cells in culture or cells removed from ethanol treated mice and stimulated in culture also occur when ethanol treatment and TLR4 activation occur in vivo. Results Phosphorylated p38, ERK, and c-Jun (nuclear were quantified with kits or by western blot using samples taken 15, 30, and 60 min after stimulation of peritoneal macrophages with lipopolysaccharide in vivo. Effects of ethanol were assessed by administering ethanol by gavage at 6 g/kg 30 min before administration of lipopolysaccharide (LPS. Cytokine concentrations in the samples of peritoneal lavage fluid and in serum were determined at 1, 2, and 6 hr after lipopolysaccharide administration. All of these data were used to measure the area under the concentration vs time curve, which provided an indication of the overall effects of ethanol in this system. Ethanol suppressed production of most pro-inflammatory cytokines to a similar degree as it inhibited key TLR4 signaling events. However, NF-κB (p65 translocation to the nucleus was not inhibited by ethanol. To determine if NF-κB composed of other subunits was inhibited, transgenic mice with a luciferase reporter were used. This revealed a reproducible inhibition of NF-κB activity, which is consistent with the observed inhibition of cytokines whose expression is known to be NF-κB dependent. Conclusion Overall, the effects of ethanol on signalling in vivo were similar to those reported for in vitro exposure to ethanol and/or lipopolysaccharide. However, inhibition of the activation of NF-κB was

  7. Pseuderanthemum palatiferum leaf extract inhibits the proinflammatory cytokines, TNF-α and IL-6 expression in LPS-activated macrophages.

    Science.gov (United States)

    Sittisart, Patcharawan; Chitsomboon, Benjamart; Kaminski, Norbert E

    2016-11-01

    The anti-inflammatory potential and underlying mechanisms of an ethanol extract of Pseuderanthemum palatiferum (EEP) leaves was investigated using LPS-activated macrophages. Our results show EEP produced a concentration-dependent suppression of TNF-α and IL-6 secretion by LPS-activated mouse peritoneal macrophages. EEP also suppressed LPS-induced TNF-α and IL-6 protein and mRNA levels in mouse-derived myeloid cell line RAW264.7. To further elucidate the molecular mechanisms responsible for impaired TNF-α and IL-6 regulation by EEP, the activation of transcription factors, NF-κB, C/EBP, and AP-1, was monitored using electrophoretic mobility shift assays. EEP suppressed LPS-induced NF-κB DNA binding activity within both the TNF-α and IL-6 promoters in RAW264.7 cells with impairment being more pronounced in the IL-6 promoter. In addition, EEP exhibited a concentration-dependent suppression of C/EBP and AP-1 DNA binding activity within the IL-6 promoter. Concordantly, IL-6 luciferase promoter reporter activity was also suppressed by EEP in transiently transfected RAW264.7 cells, upon LPS activation. EEP analysis by GC-MS and HPLC DAD-MSD revealed the presence of β-sitosterol and various polyphenols, respectively, which are known to possess anti-inflammatory activity. Collectively, these results suggest that the anti-inflammatory effects of EEP are mediated, at least in part, by modulating TNF-α and IL-6 expression through impairment of NF-κB, C/EBP, and AP-1 activity.

  8. Tat-CBR1 inhibits inflammatory responses through the suppressions of NF-κB and MAPK activation in macrophages and TPA-induced ear edema in mice

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Nam [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Kim, Dae Won [Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Kangnung-Wonju National University, Kangneung 210-702 (Korea, Republic of); Jo, Hyo Sang; Shin, Min Jea; Ahn, Eun Hee; Ryu, Eun Ji; Yong, Ji In; Cha, Hyun Ju; Kim, Sang Jin; Yeo, Hyeon Ji; Youn, Jong Kyu; Hwang, Jae Hyeok [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Jeong, Ji-Heon; Kim, Duk-Soo [Department of Anatomy, College of Medicine, Soonchunhyang University, Cheonan-Si 330-090 (Korea, Republic of); Cho, Sung-Woo [Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Park, Jinseu [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Eum, Won Sik, E-mail: wseum@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of); Choi, Soo Young, E-mail: sychoi@hallym.ac.kr [Department of Biomedical Science and Research Institute of Bioscience and Biotechnology, Hallym University, Chunchon 200-702 (Korea, Republic of)

    2015-07-15

    Human carbonyl reductase 1 (CBR1) plays a crucial role in cell survival and protects against oxidative stress response. However, its anti-inflammatory effects are not yet clearly understood. In this study, we examined whether CBR1 protects against inflammatory responses in macrophages and mice using a Tat-CBR1 protein which is able to penetrate into cells. The results revealed that purified Tat-CBR1 protein efficiently transduced into Raw 264.7 cells and inhibited lipopolysaccharide (LPS)-induced cyclooxygenase-2 (COX-2), nitric oxide (NO) and prostaglandin E{sub 2} (PGE{sub 2}) expression levels. In addition, Tat-CBR1 protein leads to decreased pro-inflammatory cytokine expression through suppression of nuclear transcription factor-kappaB (NF-κB) and mitogen activated protein kinase (MAPK) activation. Furthermore, Tat-CBR1 protein inhibited inflammatory responses in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation when applied topically. These findings indicate that Tat-CBR1 protein has anti-inflammatory properties in vitro and in vivo through inhibition of NF-κB and MAPK activation, suggesting that Tat-CBR1 protein may have potential as a therapeutic agent against inflammatory diseases. - Highlights: • Transduced Tat-CBR1 reduces LPS-induced inflammatory mediators and cytokines. • Tat-CBR1 inhibits MAPK and NF-κB activation. • Tat-CBR1 ameliorates inflammation response in vitro and in vivo. • Tat-CBR1 may be useful as potential therapeutic agent for inflammation.

  9. LOX-1 in macrophage migration in response to ox-LDL and the involvement of calpains.

    Science.gov (United States)

    Wang, Xianwei; Ding, Zufeng; Lin, Juntang; Guo, Zhikun; Mehta, Jawahar L

    2015-11-06

    Previous studies have shown that oxidized low-density lipoprotein (ox-LDL) inhibits macrophage migration, but the precise mechanisms remain unclear. Lectin-like ox-LDL receptor-1 (LOX-1) is a scavenger receptor that is expressed in macrophages and binds ox-LDL. Calpains, a family of calcium-dependent proteases, influence several aspects of cell migration. In this study, we investigated the role of LOX-1 in macrophage migration in response to ox-LDL and the involvement of calpains in this process. Peritoneal macrophages from wild type C57BL/6 mice were exposed to different concentrations of ox-LDL (1-20 μg/mL), and expression of LOX-1 and calpain-1 and -2, cell migration and intracellular calcium (Ca(2+)in) were measured. Our results showed that ox-LDL stimulated LOX-1 and calpain-2 expression, and inhibited calpain-1 expression in a dose- and time-dependent manner. Further, ox-LDL inhibited macrophage migration and increased Ca(2+)in concentration in macrophages. To further elucidate the role of LOX-1 in ox-LDL-impaired macrophage migration, we isolated peritoneal macrophages from LOX-1 knockout mice, and treated them with ox-LDL. Interestingly, calpain-1 expression was much higher, and calpain-2 expression was lower in LOX-1 knockout macrophages than in wild-type macrophages following exposure to ox-LDL. LOX-1 deletion significantly improved macrophage migration and decreased Ca(2+)in concentration. These data indicate that LOX-1 is, at least in part, responsible for the inhibitory effect of ox-LDL on macrophage migration and this process involves calpain-1 and -2.

  10. Interleukin-10 promotes B16-melanoma growth by inhibition of macrophage functions and induction of tumour and vascular cell proliferation

    Science.gov (United States)

    García-Hernández, M L; Hernández-Pando, R; Gariglio, P; Berumen, J

    2002-01-01

    The aim of this study was to investigate the mechanisms by which interleukin-10 (IL-10) induces tumour growth in a mouse-melanoma model. A B16-melanoma cell line (B16-0) was transfected with IL-10 cDNA and three clones that secreted high (B16-10), medium and low amounts of IL-10 were selected. Cell proliferation and IL-10 production were compared in vitro, and tumour growth, percentages of necrotic areas, tumour cells positive for proliferating cell nuclear antigen (PCNA), IL-10 receptor (IL-10R) and major histocompatibility complex type I (MHC-I) and II (MHC-II), as well as infiltration of macrophages, CD4+ and CD8+ lymphocytes and blood vessels were compared in vivo among IL-10-transfected and non-transfected tumours. Proliferation and tumour growth were greater for IL-10-transfected than for non-transfected cells (P < 0·001), and correlated with IL-10 concentration (r ≥ 0·79, P < 0·006). Percentages of tumour cells positive for PCNA and IL-10R were 4·4- and 16·7-fold higher, respectively, in B16-10 than in B16-0 tumours (P < 0·001). Macrophage distribution changed from a diffuse pattern in non-transfected (6·4 ± 1·7%) to a peripheral pattern in IL-10-transfected (3·8 ± 1·7%) tumours. The percentage of CD4+ lymphocytes was 7·6 times higher in B16-10 than in B16-0 tumours (P = 0·002). The expression of MHC-I molecules was present in all B16-0 tumour cells and completely negative in B16–10 tumour cells. In B16-0 tumours, 89 ± 4% of the whole tumour area was necrotic, whereas tumours produced by B16-10 cells showed only 4·3 ± 6% of necrotic areas. IL-10-transfected tumours had 17-fold more blood vessels than non-transfected tumours (61·8 ± 8% versus 3·5 ± 1·7% blood vessels/tumour; P < 0·001). All the effects induced by IL-10 were prevented in mice treated with a neutralizing anti-IL-10 monoclonal antibody. These data indicate that IL-10 could induce tumour growth in this B16-melanoma model by stimulation of tumour-cell proliferation

  11. Zuonin B Inhibits Lipopolysaccharide-Induced Inflammation via Downregulation of the ERK1/2 and JNK Pathways in RAW264.7 Macrophages

    Directory of Open Access Journals (Sweden)

    Mee-Young Lee

    2012-01-01

    Full Text Available We investigated whether Zuonin B exerts immunological effects on RAW264.7 cells. Zuonin B, isolated from flower buds of Daphne genkwa, suppressed the levels of nitric oxide and prostaglandin E2, as well as proinflammatory cytokines, such as tumor necrosis factor-α and interleukin-(IL- 6, in lipopolysaccharide-stimulated macrophages. Moreover, the compound inhibited cyclooxygenase-2 and inducible nitric oxide synthase expression. Zuonin B attenuated NF-kappaB (NF-κB activation via suppressing proteolysis of inhibitor kappa B-alpha (IκB-α and p65 nuclear translocation as well as phosphorylation of extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase. Additionally, IL-4 and IL-13 production in ConA-induced splenocytes was inhibited by Zuonin B. In conclusion, the anti-inflammatory effects of Zuonin B are attributable to the suppression of proinflammatory cytokines and mediators via blockage of NF-κB and AP-1 activation. Based on these findings, we propose that Zuonin B is potentially an effective functional chemical candidate for the prevention of inflammatory diseases.

  12. Koumine Attenuates Lipopolysaccaride-Stimulated Inflammation in RAW264.7 Macrophages, Coincidentally Associated with Inhibition of NF-κB, ERK and p38 Pathways

    Directory of Open Access Journals (Sweden)

    Zhihang Yuan

    2016-03-01

    Full Text Available Medicinal herbal plants have been commonly used for intervention of different diseases and health enhancement worldwide. Koumine, an alkaloid monomer found abundantly in Gelsemium plants, can be effectively used as an anti-inflammatory medication. In this study, the mechanisms associated with the preventative effect of koumine on lipopolysaccharide (LPS-mediated inflammation in RAW264.7 macrophages were investigated. Koumine induced a decrease in the level of inducible nitric oxide synthase (iNOS protein, concomitant reduction in the production of nitric oxide (NO and reduction of the levels of interleukin (IL-6, tumor necrosis factor-α (TNF-α and IL-1β. Furthermore, koumine decreased the phosphorylation of p65 and inhibited nuclear factor κ Bα (IκBα proteins, resulting in lower production of nuclear factor (NF-κB transactivation. Koumine also induced a decrease in the phosphorylation of extracellular-signal-regulated kinases (ERK and p38 in RAW264 cells. In conclusion, these findings reveal that koumine decreases the productions of pro-inflammatory mediators though the suppression of p38 and ERK MAPK phosphorylation and the inhibition of NF-κB activation in RAW264.7 cells.

  13. Protective effects of a standard extract of Mangifera indica L. (VIMANG) against mouse ear edemas and its inhibition of eicosanoid production in J774 murine macrophages.

    Science.gov (United States)

    Garrido, G; González, D; Lemus, Y; Delporte, C; Delgado, R

    2006-06-01

    A standard aqueous extract of Mangifera indica L., used in Cuba as antioxidant under the brand name VIMANG, was tested in vivo for its anti-inflammatory activity, using commonly accepted assays. The standard extract of M. indica, administered orally (50-200mg/kg body wt.), reduced ear edema induced by arachidonic acid (AA) and phorbol myristate acetate (PMA) in mice. In the PMA model, M. indica extract also reduced myeloperoxidase (MPO) activity. In vitro studies were performed using macrophage cell line J774 stimulated with pro-inflammatory stimuli lipopolysaccharide-interferon gamma (LPS-IFNgamma) or calcium ionophore A23187 to determine prostaglandin PGE(2) or leukotriene LTB(4) release, respectively. The extract inhibited the induction of PGE(2) and LTB(4) with IC(50) values of 21.7 and 26.0microg/ml, respectively. Mangiferin (a glucosylxanthone isolated from the extract) also inhibited these AA metabolites (PGE(2), IC(50) value=17.2microg/ml and LTB(4), IC(50) value=2.1microg/ml). These results represent an important contribution to the elucidation of the mechanism involved in the anti-inflammatory and anti-nociceptive effects reported for the standard extract of M. indica VIMANG.

  14. Expression and regulation of HIF-1 alpha in macrophages under inflammatory conditions; significant reduction of VEGF by CaMKII inhibitor

    NARCIS (Netherlands)

    Westra, Johanna; Brouwer, Elisabeth; van Roosmalen, Ingrid A. M.; Doornbos-van der Meer, Berber; van Leeuwen, Miek A.; Posthumus, Marcel D.; Kallenberg, Cees G. M.; WESTRA, H

    2010-01-01

    Background: Macrophages expressing the pro-angiogenic transcription factor hypoxia-inducible factor (HIF)-1alpha have been demonstrated in rheumatoid arthritis (RA) in the synovial tissue. Aim of the present study was to investigate intracellular signal transduction regulation of pro-inflammatory HI

  15. Salvianolic acid B inhibits macrophage uptake of modified low density lipoprotein (mLDL) in a scavenger receptor CD36-dependent manner

    Science.gov (United States)

    Bao, Yi; Wang, Li; Xu, Yanni; Yang, Yuan; Wang, Lifei; Si, Shuyi; Cho, Sunghee; Hong, Bin

    2012-01-01

    CD36, a class B scavenger receptor, has been implicated in the pathogenesis of a host of vascular inflammatory diseases. Through a high-throughput screening (HTS) assay for CD36 antagonist, we previously identified salvianolic acid B (SAB), a hydrophilic component derived from the herb Danshen, as a potential candidate. Danshen, the dried roots of Salvia miltiorrhiza, has been widely used in China for the prevention and treatment of atherosclerosis-related disorders. Previous studies showed that SAB acted as an anti-oxidant by preventing lipid peroxidation and oxidized LDL (oxLDL) formation. The present study was to investigate the specificity and efficacy of SAB in the inhibition of CD36-mediated lipid uptake. SAB reduced modified LDL (mLDL) uptake in a dose-dependent manner in phorbol-12-myristate-13-acetate (PMA)-stimulated THP-1 and RAW 264.7 cells. In the CD36 silenced THP-1 cells, SAB had no effect in reducing mLDL uptake, whereas its over-expression in CHO cells reinstates the effect, indicating a specific involvement of SAB in antagonizing the CD36's function. Surface plasmon resonance (SPR) analysis revealed a direct binding of SAB to CD36 with a high affinity (KD =3.74 μM), confirming physical interactions of SAB with the receptor. Additionally, SAB reduced oxLDL-induced CD36 gene expression in the cultured cell lines and primary macrophages. In ApoE KO mice fed a high fat diet, SAB reduced CD36 gene expression and lipid uptake in macrophages, showing its ability to antagonize CD36 pathways in vivo. These results demonstrate that SAB is an effective CD36 antagonist and suggest SAB as a potential anti-atherosclerotic agent. PMID:22658257

  16. UCLA1 aptamer inhibition of human immunodeficiency virus type 1 subtype C primary isolates in macrophages and selection of resistance

    CSIR Research Space (South Africa)

    Mufhandu, Hazel T

    2016-09-01

    Full Text Available We have previously shown that the aptamer, UCLA1, is able to inhibit HIV-1 replication in peripheral blood mononuclear cells (PBMCs) by binding to residues in gp120. In this study we examined whether UCLA1 was effective against HIV-1 subtype C...

  17. SseK1 and SseK3 Type III Secretion System Effectors Inhibit NF-κB Signaling and Necroptotic Cell Death in Salmonella-Infected Macrophages

    Science.gov (United States)

    Günster, Regina A.; Matthews, Sophie A.; Holden, David W.

    2017-01-01

    ABSTRACT Within host cells such as macrophages, Salmonella enterica translocates virulence (effector) proteins across its vacuolar membrane via the SPI-2 type III secretion system. Previously, it was shown that when expressed ectopically, the effectors SseK1 and SseK3 inhibit tumor necrosis factor alpha (TNF-α)-induced NF-κB activation. In this study, we show that ectopically expressed SseK1, SseK2, and SseK3 suppress TNF-α-induced, but not Toll-like receptor 4- or interleukin-induced, NF-κB activation. Inhibition required a DXD motif in SseK1 and SseK3, which is essential for the transfer of N-acetylglucosamine to arginine residues (arginine-GlcNAcylation). During macrophage infection, SseK1 and SseK3 inhibited NF-κB activity in an additive manner. SseK3-mediated inhibition of NF-κB activation did not require the only known host-binding partner of this effector, the E3-ubiquitin ligase TRIM32. SseK proteins also inhibited TNF-α-induced cell death during macrophage infection. Despite SseK1 and SseK3 inhibiting TNF-α-induced apoptosis upon ectopic expression in HeLa cells, the percentage of infected macrophages undergoing apoptosis was SseK independent. Instead, SseK proteins inhibited necroptotic cell death during macrophage infection. SseK1 and SseK3 caused GlcNAcylation of different proteins in infected macrophages, suggesting that these effectors have distinct substrate specificities. Indeed, SseK1 caused the GlcNAcylation of the death domain-containing proteins FADD and TRADD, whereas SseK3 expression resulted in weak GlcNAcylation of TRADD but not FADD. Additional, as-yet-unidentified substrates are likely to explain the additive phenotype of a Salmonella strain lacking both SseK1 and SseK3. PMID:28069818

  18. Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation

    Directory of Open Access Journals (Sweden)

    Lindenmaier Werner

    2010-04-01

    Full Text Available Abstract Background Toll-like receptor (TLR 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies are applied to block translocation of secreted and cell surface molecules from the ER to the cell surface resulting in functional inhibition of the target protein. Here we describe generation and application of a functional anti-TLR2 ER intrabody (αT2ib which was generated from an antagonistic monoclonal antibody (mAb towards human and murine TLR2 (T2.5 to inhibit the function of TLR2. αT2ib is a scFv fragment comprising the variable domain of the heavy chain and the variable domain of the light chain of mAb T2.5 linked together by a synthetic (Gly4Ser3 amino acid sequence. Results Coexpression of αT2ib and mouse TLR2 in HEK293 cells led to efficient retention and accumulation of TLR2 inside the ER compartment. Co-immunoprecipitation of human TLR2 with αT2ib indicated interaction of αT2ib with its cognate antigen within cells. αT2ib inhibited NF-κB driven reporter gene activation via TLR2 but not through TLR3, TLR4, or TLR9 if coexpressed in HEK293 cells. Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding αT2ib into HEK293 cells demonstrated high efficiency of the TLR2-αT2ib interaction. The αT2ib open reading frame was integrated into an adenoviral cosmid vector for production of recombinant adenovirus (AdV-αT2ib. Transduction with AdVαT2ib specifically inhibited TLR2 surface expression of murine RAW264.7 and primary macrophages derived from bone marrow (BMM. Furthermore, TLR2 activation dependent TNFα mRNA accumulation, as well

  19. NPFF2 receptor is involved in the modulatory effects of neuropeptide FF for macrophage cell line.

    Science.gov (United States)

    Sun, Yu-long; Sun, Tao; Zhang, Xiao-yuan; He, Ning; Zhuang, Yan; Li, Jing-yi; Fang, Quan; Wang, Kai-rong; Wang, Rui

    2014-05-01

    Neuropeptide FF (NPFF) interacts with specific receptors to regulate diverse biological processes. Its modulatory effect in the immune field, however, has not been fully explored yet. Here, we report that NPFF2 receptors may be functionally expressed in two immune cell models, the primary peritoneal macrophage and RAW 264.7 macrophage. Firstly, the mRNA levels of NPFF2 receptor were up-regulated in macrophages when treated with LPS for 24 to 72 h. Subsequently, our data hinted that NPFF regulates the viability of both kinds of macrophages. After treatment with RF9, a reported antagonist for both NPFF receptors, delayed or inhibited the NPFF-induced macrophages viability augmentation, suggesting the involvement of NPFF2 receptor. Furthermore, down-regulation of nitric oxide (NO) synthases (NOSs) partially significantly inhibited the viability augmentation of macrophages induced by NPFF, implying a nitric oxide synthases- dependent pathway is involved. However, the NOSs are not the only route by which NPFF affects the viability of macrophages. Pharmacological inhibitors of NF-κB signal pathway also blocked the NPFF-induced macrophages growth, suggesting the involvement of the NF-κB signal pathway. The regulation activity of NPFF for macrophages suggests that NPFF could act as a potential hormone in the control of immune system. Collectively, our data provide new evidence about the immune modulatory effect of NPFF, which will be helpful in extending the scope of NPFF functions.

  20. Interleukin-10 inhibits burst-forming unit-erythroid growth by suppression of endogenous granulocyte-macrophage colony-stimulating factor production from T cells.

    Science.gov (United States)

    Oehler, L; Kollars, M; Bohle, B; Berer, A; Reiter, E; Lechner, K; Geissler, K

    1999-02-01

    Numerous cytokines released from accessory cells have been shown to exert either stimulatory or inhibitory growth signals on burst-forming unit-erythroid (BFU-E) growth. Because of its cytokine synthesis-inhibiting effects on T cells and monocytes, interleukin-10 (IL-10) may be a potential candidate for indirectly affecting erythropoiesis. We investigated the effects of IL-10 on BFU-E growth from normal human peripheral blood mononuclear cells (PBMC) using a clonogenic progenitor cell assay. The addition of recombinant human IL-10 to cultures containing recombinant human erythropoietin suppressed BFU-E growth in a dose-dependent manner (by 55.2%, range 47.3-63.3%, p cultivating highly enriched CD34+ cells. BFU-E growth from PBMC also was markedly suppressed in the presence of a neutralizing anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) antibody (by 48.7%, range 32.9-61.2% inhibition,p < 0.01), but not by neutralizing antibodies against granulocyte colony-stimulating factor and interleukin-3. This suggests a stimulatory role of endogenously released GM-CSF on BFU-E formation. Also, the addition of exogenous GM-CSF completely restored IL-10-induced suppression of BFU-E growth. To determine the cellular source of GM-CSF production, we analyzed GM-CSF levels in suspension cultures containing PBMC that were either depleted of monocytes or T cells. Monocyte-depleted PBMC showed spontaneous production of increasing amounts of GM-CSF on days 3, 5, and 7, respectively, which could be suppressed by IL-10, whereas GM-CSF levels did not increase in cultures containing T-cell-depleted PBMC. Our data indicate that IL-10 inhibits the growth of erythroid progenitor cells in vitro, most likely by suppression of endogenous GM-CSF production from T cells.

  1. Toxicity of mercury in macrophages. Structure and function of macrophages after experimental mercury exposure

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, M.M.

    1995-12-31

    Mercury is recognized as an environmental heavy metal pollutant with a toxic effect on living organisms. The toxicity of this heavy metal at cellular level is described for many types of cells. Macrophages are ubiquitous in the organism and play a central role in the non-specific defence barrier against intruding micro-organisms. As a first line of defence, macrophages are crucial for the course of generalized infection, for instance with herpes simplex virus. Functions such as phagocytosis, migration, activation during infection and cytokine production are important in this context. Mercury, detectable by auto metallography, is found in the lysosomes of macrophages and this accumulation is dependent upon dose and length of time of mercury exposure. But higher concentrations cause auto interference, which indicates that mercury accumulation is dependent on lysosome functional integrity and that mercury inhibits lysosome functions. In mice intraperitoneally exposed to mercury chloride, mercury is found localized in the lysosomes of macrophages in the spleen, thymus, lymph nodes and liver as well as in peritoneal macrophages. The effect of mercury on a virus infection was examined in studies of the course of infection in mice treated with mercury and infected with herpes simplex virus type 2 (HSV-2) under further exposure to mercury. To further elucidate aspects of interactions between heavy metals and macrophages and their eventual significance for the antiviral effect of macrophages, the effect of mercury on cell respiratory burst capacity and the influence of mercury on cell production of and reaction to cytokines was examined. This thesis shows that mercury is immunotoxic in that it affects macrophages both with regard to the viability and function of the cells. This is also valid for mercury concentrations that do not result in apparent pathological changes. (EG) 98 refs.

  2. Schisandrin B inhibits cell growth and induces cellular apoptosis and autophagy in mouse hepatocytes and macrophages: implications for its hepatotoxicity

    Directory of Open Access Journals (Sweden)

    Zhang Y

    2015-04-01

    Kip1 and checkpoint kinase 1. Furthermore, Sch B markedly increased the apoptosis of AML-12 and RAW 264.7 cells with a decrease in the expression of B-cell lymphoma-extra-large and (Bcl-xl B-cell lymphoma 2 (Bcl-2, but an increase in the expression of B-cell lymphoma 2-associated X protein (Bax. Sch B promoted the cleavage of caspase 3 and poly-adenosine diphosphate-ribose polymerase (PARP in both cell lines. Additionally, Sch B significantly induced autophagy of AML-12 and RAW 264.7 cells. Sch B inhibited the activation of phosphatidylinositol 3-kinase (PI3K/protein kinase B (Akt/mammalian target of rapamycin (mTOR signaling pathway, as indicated by their altered phosphorylation, contributing to the proautophagic effect of Sch B. Taken together, our findings show that the inducing effects of Sch B on cell cycle arrest, apoptosis, and autophagy may contribute to its liver toxic effects, which might provide a clue for the investigation of the molecular toxic targets and underlying mechanisms for Sch B-induced hepatotoxicity in herbal consumers. More studies are warranted to fully delineate the underlying mechanisms, efficacy, and safety of Sch B for clinical use.Keywords: herbal medicine, liver toxicity, mTOR, Bcl-2, AML-12 cell, RAW 264.7 cell

  3. Reactive-oxygen-species-mediated P. aeruginosa killing is functional in human cystic fibrosis macrophages.

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    Noemi Cifani

    Full Text Available Pseudomonas aeruginosa is the most common pathogen for chronic lung infection in cystic fibrosis (CF patients. About 80% of adult CF patients have chronic P. aeruginosa infection, which accounts for much of the morbidity and most of the mortality. Both bacterial genetic adaptations and defective innate immune responses contribute to the bacteria persistence. It is well accepted that CF transmembrane conductance regulator (CFTR dysfunction impairs the airways-epithelium-mediated lung defence; however, other innate immune cells also appear to be affected, such as neutrophils and macrophages, which thus contribute to this infectious pathology in the CF lung. In macrophages, the absence of CFTR has been linked to defective P. aeruginosa killing, increased pro-inflammatory cytokine secretion, and reduced reactive oxygen species (ROS production. To learn more about macrophage dysfunction in CF patients, we investigated the generation of the oxidative burst and its impact on bacterial killing in CF macrophages isolated from peripheral blood or lung parenchyma of CF patients, after P. aeruginosa infection. Our data demonstrate that CF macrophages show an oxidative response of similar intensity to that of non-CF macrophages. Intracellular ROS are recognized as one of the earliest microbicidal mechanisms against engulfed pathogens that are activated by macrophages. Accordingly, NADPH inhibition resulted in a significant increase in the intracellular bacteria survival in CF and non-CF macrophages, both as monocyte-derived macrophages and as lung macrophages. These data strongly suggest that the contribution of ROS to P. aeruginosa killing is not affected by CFTR mutations.

  4. Endotoxin contamination of apolipoprotein A-I: effect on macrophage proliferation--a cautionary tale.

    Science.gov (United States)

    Jin, Xueting; Xu, Qing; Champion, Keith; Kruth, Howard S

    2015-05-01

    This technical report addresses the problem of endotoxin contamination of apolipoprotein reagents. Using a bromodeoxyuridine incorporation cell proliferation assay, we observed that human plasma ApoA-I as low as 1 μg/ml resulted in a >90% inhibition in macrophage proliferation. However, not all ApoA-I from different sources showed this effect. We considered the possibility that endotoxin contamination of the apolipoproteins contributed to the differential inhibition of macrophage cell proliferation. Endotoxin alone very potently inhibited macrophage proliferation (0.1 ng/ml inhibited macrophage proliferation>90%). Measurement of endotoxin levels in the apolipoprotein products, including an analysis of free versus total endotoxin, the latter which included endotoxin that was masked due to binding to protein, suggested that free endotoxin mediated inhibition of macrophage proliferation. Despite the use of an advanced endotoxin removal procedure and agents commonly used to inhibit endotoxin action, the potency of endotoxin precluded successful elimination of endotoxin effect. Our findings show that endotoxin contamination can significantly influence apparent apolipoprotein-mediated cell effects (or effects of any other biological products), especially when these products are tested on highly endotoxin-sensitive cells, such as macrophages.

  5. SIRT2 ameliorates lipopolysaccharide-induced inflammation in macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ae Sin; Jung, Yu Jin; Kim, Dal; Nguyen-Thanh, Tung [Department of Internal Medicine, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Kang, Kyung Pyo [Department of Internal Medicine, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Research Institute of Clinical Medicine of Chonbuk National University, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Lee, Sik [Department of Internal Medicine, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Park, Sung Kwang [Department of Internal Medicine, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Research Institute of Clinical Medicine of Chonbuk National University, Chonbuk National University Hospital, Jeonju (Korea, Republic of); Kim, Won, E-mail: kwon@jbnu.ac.kr [Department of Internal Medicine, Chonbuk National University Medical School, Jeonju (Korea, Republic of); Research Institute of Clinical Medicine of Chonbuk National University, Chonbuk National University Hospital, Jeonju (Korea, Republic of)

    2014-08-08

    Highlights: • Knockout of SIRT2 attenuates lipopolysaccharide-induced iNOS expression. • Lipopolysaccharide-induced NO production is decreased in SIRT2 KO macrophage. • SIRT2 deficiency suppresses lipopolysaccharide-induced ROS production in macrophage. • M1-macrophage related factors are decreased in SIRT2 deficient cells. • SIRT2 deficiency decreases lipopolysaccharide-induced activation of NFκB. - Abstract: Introduction: SIRT2 is a NAD(+)-dependent deacetylases and associated with numerous processes such as infection, carcinogenesis, DNA damage and cell cycle regulation. However, the role of SIRT2 in inflammatory process in macrophage remains unclear. Materials and methods: In the present study, we have evaluated the regulatory effects of SIRT2 in lipopolysaccharide (LPS)-stimulated macrophages isolated from SIRT2 knockout (KO) and wild type (WT) mice or Raw264.7 macrophage cells. As inflammatory parameters, expression of inducible nitric oxide synthase (iNOS), the productions of nitric oxide, reactive oxygen species (ROS) and M1-macrophage-related factors were evaluated. We also examined the effects of SIRT2 on activation of nuclear factor-kappaB (NFκB) signaling. Results: SIRT2 deficiency inhibits LPS-induced iNOS mRNA and protein expression in bone marrow derived macrophages. SIRT2-siRNA transfection also suppressed LPS-induced iNOS expression in Raw264.7 macrophage cells. Bone marrow derived macrophages isolated from SIRT2 KO mice produced lower nitric oxide and expressed lower levels of M1-macrophage related markers including iNOS and CD86 in response to LPS than WT mice. Decrease of SIRT2 reduced the LPS-induced reactive oxygen species production. Deficiency of SIRT2 resulted in inhibition of NFκB activation through reducing the phosphorylation and degradation of IκBα. The phosphorylation and nuclear translocation of p65 was significantly decreased in SIRT2-deficient macrophages after LPS stimulation. Discussion: Our data suggested that

  6. CDDO-Me Redirects Activation of Breast Tumor Associated Macrophages.

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    Michael S Ball

    Full Text Available Tumor-associated macrophages can account for up to 50% of the tumor mass in breast cancer patients and high TAM density is associated with poor clinical prognosis. Because TAMs enhance tumor growth, development, and metastatic potential, redirection of TAM activation may have significant therapeutic benefit. Our studies in primary human macrophages and murine breast TAMs suggest that the synthetic oleanane triterpenoid CDDO-methyl ester (CDDO-Me reprograms the activation profile of TAMs from tumor-promoting to tumor-inhibiting. We show that CDDO-Me treatment inhibits expression of IL-10 and VEGF in stimulated human M2 macrophages and TAMs but increases expression of TNF-α and IL-6. Surface expression of CD206 and CD163, which are characteristic of M2 activation, is significantly attenuated by CDDO-Me. In contrast, CDDO-Me up-regulates surface expression of HLA-DR and CD80, which are markers of M1 activation, and importantly potentiates macrophage activation of autologous T cells but inhibits endothelial cell vascularization. These results show for the first time that CDDO-Me redirects activation of M2 macrophages and TAMs from immune-suppressive to immune-stimulatory, and implicate a role for CDDO-Me as an immunotherapeutic in the treatment of breast and potentially other types of cancer.

  7. Euscaphic acid isolated from roots of Rosa rugosa inhibits LPS-induced inflammatory responses via TLR4-mediated NF-κB inactivation in RAW 264.7 macrophages.

    Science.gov (United States)

    Kim, In-Tae; Ryu, Suran; Shin, Ji-Sun; Choi, Jung-Hye; Park, Hee-Juhn; Lee, Kyung-Tae

    2012-06-01

    As an attempt to search for bioactive natural products exerting anti-inflammatory activity, we have evaluated the anti-inflammatory effects of euscaphic acid (19α-hydroxyursane-type triterpenoids, EA) isolated from roots of Rosa rugosa and its underlying molecular mechanisms in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. EA concentration-dependently reduced the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) induced by LPS in RAW 264.7 macgophages. Consistent with these data, expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and iNOS, COX-2, TNF-α, and IL-1β mRNA were inhibited by EA in a concentration-dependent manner. In addition, EA attenuated LPS-induced DNA binding and transcriptional activity of nuclear factor-kappa B (NF-κB), which was accompanied by a parallel reduction of degradation and phosphorylation of inhibitory kappa Bα (IκBα) and consequently by decreased nuclear translocation of p65 subunit of NF-κB. Pretreatment with EA significantly inhibited the LPS-induced phosphorylation of IκB kinase β (IKKβ), p38, and JNK, whereas the phosphorylation of ERK1/2 was unaffected. Furthermore, EA interfered with the LPS-induced clustering of TNF receptor-associated factor 6 (TRAF6) with interleukin receptor associated kinase 1 (IRAK1) and transforming growth factor-β-activated kinase 1 (TAK1). Taken together, these results suggest that EA inhibits LPS-induced inflammatory responses by interference with the clustering of TRAF6 with IRAK1 and TAK1, resulting in blocking the activation of IKK and MAPKs signal transduction to downregulate NF-κB activations.

  8. Perfluorocarbon inhibits lipopolysaccharide-induced macrophage inflammatory protein-2 expression and activation of ATF-2 and c-Jun in A549 pulmonary epithelial cells.

    Science.gov (United States)

    Hu, Y; Li, C S; Li, Y Q; Liang, Y; Cao, L; Chen, L A

    2016-04-30

    The signaling pathway that mediates the anti-inflammatory effects of perfluorocarbon (PFC) in alveolar epithelial cells treated with lipopolysaccharide (LPS) remains unclear. To evaluate the role of macrophage-inflammatory protein-2 (MIP-2), four A549 treatment groups were utilized: (1) untreated control, (2) 10 μg/mL of LPS, (3) 10 μg/mL of LPS+30% PFC and (4) 30% PFC. MIP-2 mRNA expression was determined by qPCR and ELISA. Mitogen-activated protein kinase (MAPK) activation was determined by Western blot analysis, and MIP-2 expression was determined by qPCR following treatment with MAPK inhibitors. PFC suppressed LPS-induced MIP-2 mRNA levels (P≤0.035) and MIP-2 secretion (P≤0.046). LPS induced ATF-2 and c-Jun phosphorylation, which was suppressed by PFC. Finally, inhibitors of ERK, JNK, and p38 suppressed LPS-induced MIP-2 mRNA expression. Thus, PFC inhibits LPS-induced MIP-2 expression and ATF-2 and c-Jun phosphorylation. To fully explore the therapeutic potential of PFC for acute lung injury (ALI), in vivo analyses are required to confirm these effects.

  9. Neocryptotanshinone inhibits lipopolysaccharide-induced inflammation in RAW264.7 macrophages by suppression of NF-κB and iNOS signaling pathways

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    Chuanhong Wu

    2015-07-01

    Full Text Available Neocryptotanshinone (NCTS is a natural product isolated from traditional Chinese herb Salvia miltiorrhiza Bunge. In this study, we investigated its anti-inflammatory effects in lipopolysaccharide (LPS-stimulated mouse macrophage (RAW264.7 cells. MTT results showed that NCTS partly reversed LPS-induced cytotoxicity. Real-time PCR results showed that NCTS suppressed LPS-induced mRNA expression of inflammatory cytokines, including tumor necrosis factor α (TNFα, interleukin-6 (IL-6 and interleukin-1β (IL-1β. Moreover, NCTS could decrease LPS-induced nitric oxide (NO production. Western blotting results showed that NCTS could down-regulate LPS-induced expression of inducible nitric oxide synthase (iNOS, p-IκBα, p-IKKβ and p-NF-κB p65 without affecting cyclooxygenase-2 (COX-2. In addition, NCTS inhibited LPS-induced p-NF-κB p65 nuclear translocation. In conclusion, these data demonstrated that NCTS showed anti-inflammatory effect by suppression of NF-κB and iNOS signaling pathways.

  10. Commercial Honeybush (Cyclopia spp.) Tea Extract Inhibits Osteoclast Formation and Bone Resorption in RAW264.7 Murine Macrophages-An in vitro Study.

    Science.gov (United States)

    Visagie, Amcois; Kasonga, Abe; Deepak, Vishwa; Moosa, Shaakirah; Marais, Sumari; Kruger, Marlena C; Coetzee, Magdalena

    2015-10-28

    Honeybush tea, a sweet tasting caffeine-free tea that is indigenous to South Africa, is rich in bioactive compounds that may have beneficial health effects. Bone remodeling is a physiological process that involves the synthesis of bone matrix by osteoblasts and resorption of bone by osteoclasts. When resorption exceeds formation, bone remodeling can be disrupted resulting in bone diseases such as osteoporosis. Osteoclasts are multinucleated cells derived from hematopoietic precursors of monocytic lineage. These precursors fuse and differentiate into mature osteoclasts in the presence of receptor activator of NF-kB ligand (RANKL), produced by osteoblasts. In this study, the in vitro effects of an aqueous extract of fermented honeybush tea were examined on osteoclast formation and bone resorption in RAW264.7 murine macrophages. We found that commercial honeybush tea extract inhibited osteoclast formation and TRAP activity which was accompanied by reduced bone resorption and disruption of characteristic cytoskeletal elements of mature osteoclasts without cytotoxicity. Furthermore, honeybush tea extract decreased expression of key osteoclast specific genes, matrix metalloproteinase-9 (MMP-9), tartrate resistant acid phosphatase (TRAP) and cathepsin K. This study demonstrates for the first time that honeybush tea may have potential anti-osteoclastogenic effects and therefore should be further explored for its beneficial effects on bone.

  11. Astrocyte production of the chemokine macrophage inflammatory protein-2 is inhibited by the spice principle curcumin at the level of gene transcription

    Directory of Open Access Journals (Sweden)

    Santoro Thomas J

    2005-02-01

    Full Text Available Abstract Background In neuropathological processes associated with neutrophilic infiltrates, such as experimental allergic encephalitis and traumatic injury of the brain, the CXC chemokine, macrophage inflammatory protein-2 (MIP-2 is thought to play a pivotal role in the induction and perpetuation of inflammation in the central nervous system (CNS. The origin of MIP-2 in inflammatory disorders of the brain has not been fully defined but astrocytes appear to be a dominant source of this chemokine. Curcumin is a spice principle in, and constitutes approximately 4 percent of, turmeric. Curcumin's immunomodulating and antioxidant activities suggest that it might be a useful adjunct in the treatment of neurodegenerative illnesses characterized by inflammation. Relatively unexplored, but relevant to its potential therapeutic efficacy in neuroinflammatory syndromes is the effect of curcumin on chemokine production. To examine the possibility that curcumin may influence CNS inflammation by mechanisms distinct from its known anti-oxidant activities, we studied the effect of this spice principle on the synthesis of MIP-2 by astrocytes. Methods Primary astrocytes were prepared from neonatal brains of CBA/CaJ mice. The cells were stimulated with lipopolysaccharide in the presence or absence of various amount of curcumin or epigallocatechin gallate. MIP-2 mRNA was analyzed using semi-quantitative PCR and MIP-2 protein production in the culture supernatants was quantified by ELISA. Astrocytes were transfected with a MIP-2 promoter construct, pGL3-MIP-2, and stimulated with lipopolysaccharide in the presence or absence of curcumin. Results The induction of MIP-2 gene expression and the production of MIP-2 protein were inhibited by curcumin. Curcumin also inhibited lipopolysaccharide-induced transcription of the MIP-2 promoter reporter gene construct in primary astrocytes. However MIP-2 gene induction by lipopolysaccharide was not inhibited by another anti

  12. Inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells by the norsesterterpene peroxide, epimuqubilin A.

    Science.gov (United States)

    Cheenpracha, Sarot; Park, Eun-Jung; Rostama, Bahman; Pezzuto, John M; Chang, Leng Chee

    2010-03-01

    Seven norsesterterpene peroxides: epimuqubilin A (1), muqubilone B (2), unnamed cyclic peroxide ester (3), epimuqubilin B (4), sigmosceptrellin A methyl ester (5), sigmosceptrellin A (6), and sigmosceptrellin B methyl ester (7), isolated from the marine sponge Latrunculia sp., were examined with regard to their effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cells. The results indicated epimuqubilin A (1) possessed potent NO inhibitory activity against lipopolysaccharide (LPS)-induced nitric oxide release with an IC(50) value of 7.4 microM, a level three times greater than the positive control, L-N(G)-monomethyl arginine citrate, followed by 6 (sigmosceptrellin A, IC(50) = 9.9 microM), whereas other compounds exhibited only modest activity (Table 1). These compounds did not show appreciable cytotoxicity at their IC(50) values for NO-inhibitory activity. The structure-activity upon NO inhibition could be summarized as follows: (1) a monocyclic carbon skeleton framework was essential for activity, (2) free acids gave higher activity, (3) the orientation of H3-22 with an equatorial position increased activity, and (4) a bicyclic structure reduced activity. This is the first report of a norsesterterpene peroxide with NO-inhibitory activity. In addition, compounds 1-7 were also evaluated for their inhibitory activities in the yeast glycogen synthase kinase-3beta assay. In summary, several norsesterterpene peroxides showed novel biological activities of inhibition in NO production, suggesting that these might provide leads for anti-inflammatory or cancer chemopreventive agents.

  13. Impact of alginate-producing Pseudomonas aeruginosa on alveolar macrophage apoptotic cell clearance.

    Science.gov (United States)

    McCaslin, Charles A; Petrusca, Daniela N; Poirier, Christophe; Serban, Karina A; Anderson, Gregory G; Petrache, Irina

    2015-01-01

    Pseudomonas aeruginosa infection is a hallmark of lung disease in cystic fibrosis. Acute infection with P. aeruginosa profoundly inhibits alveolar macrophage clearance of apoptotic cells (efferocytosis) via direct effect of virulence factors. During chronic infection, P. aeruginosa evades host defense by decreased virulence, which includes the production or, in the case of mucoidy, overproduction of alginate. The impact of alginate on innate immunity, in particular on macrophage clearance of apoptotic cells is not known. We hypothesized that P. aeruginosa strains that exhibit reduced virulence impair macrophage clearance of apoptotic cells and we investigated if the polysaccharide alginate produced by mucoid P. aeruginosa is sufficient to inhibit alveolar macrophage efferocytosis. Rat alveolar or human peripheral blood monocyte (THP-1)-derived macrophage cell lines were exposed in vitro to exogenous alginate or to wild type or alginate-overproducing mucoid P. aeruginosa prior to challenge with apoptotic human Jurkat T-lymphocytes. The importance of LPS contamination and that of structural integrity of alginate polymers was tested using alginate of different purities and alginate lyase, respectively. Alginate inhibited alveolar macrophage efferocytosis in a dose- and time-dependent manner. This effect was augmented but not exclusively attributed to lipopolysaccharide (LPS) present in alginates. Alginate-producing P. aeruginosa inhibited macrophage efferocytosis by more than 50%. A mannuronic-specific alginate lyase did not restore efferocytosis inhibited by exogenous guluronic-rich marine alginate, but had a marked beneficial effect on efferocytosis of alveolar macrophages exposed to mucoid P. aeruginosa. Despite decreased virulence, mucoid P. aeruginosa may contribute to chronic airway inflammation through significant inhibition of alveolar clearance of apoptotic cells and debris. The mechanism by which mucoid bacteria inhibit efferocytosis may involve alginate

  14. FoxO1 regulates allergic asthmatic inflammation through regulating polarization of the macrophage inflammatory phenotype.

    Science.gov (United States)

    Chung, Sangwoon; Lee, Tae Jin; Reader, Brenda F; Kim, Ji Young; Lee, Yong Gyu; Park, Gye Young; Karpurapu, Manjula; Ballinger, Megan N; Qian, Feng; Rusu, Luiza; Chung, Hae Young; Unterman, Terry G; Croce, Carlo M; Christman, John W

    2016-04-05

    Inflammatory monocyte and tissue macrophages influence the initiation, progression, and resolution of type 2 immune responses, and alveolar macrophages are the most prevalent immune-effector cells in the lung. While we were characterizing the M1- or M2-like macrophages in type 2 allergic inflammation, we discovered that FoxO1 is highly expressed in alternatively activated macrophages. Although several studies have been focused on the fundamental role of FoxOs in hematopoietic and immune cells, the exact role that FoxO1 plays in allergic asthmatic inflammation in activated macrophages has not been investigated. Growing evidences indicate that FoxO1 acts as an upstream regulator of IRF4 and could have a role in a specific inflammatory phenotype of macrophages. Therefore, we hypothesized that IRF4 expression regulated by FoxO1 in alveolar macrophages is required for established type 2 immune mediates allergic lung inflammation. Our data indicate that targeted deletion of FoxO1 using FoxO1-selective inhibitor AS1842856 and genetic ablation of FoxO1 in macrophages significantly decreases IRF4 and various M2 macrophage-associated genes, suggesting a mechanism that involves FoxO1-IRF4 signaling in alveolar macrophages that works to polarize macrophages toward established type 2 immune responses. In response to the challenge of DRA (dust mite, ragweed, and Aspergillus) allergens, macrophage specific FoxO1 overexpression is associated with an accentuation of asthmatic lung inflammation, whereas pharmacologic inhibition of FoxO1 by AS1842856 attenuates the development of asthmatic lung inflammation. Thus, our study identifies a role for FoxO1-IRF4 signaling in the development of alternatively activated alveolar macrophages that contribute to type 2 allergic airway inflammation.

  15. Endomorphins 1 and 2 inhibit IL-10 and IL-12 production and innate immune functions, and potentiate NF-kappaB DNA binding in THP-1 differentiated to macrophage-like cells.

    Science.gov (United States)

    Azuma, Y; Ohura, K

    2002-09-01

    We evaluated immunological effects of opioid peptides endomorphins 1 and 2 on the production of interleukin-10 (IL-10) and IL-12 cytokines, functions related to innate immunity and NF-kappaB DNA binding in human cell line THP-1. Endomorphins 1 and 2 inhibited lipopolysaccharide (LPS)-stimulated IL-10 and IL-12 production in THP-1 differentiated to macrophage-like cells by phorbol 12-myristate 13-acetate (PMA). Similarly, they suppressed LPS-stimulated IL-10 and IL-12 production in THP-1 matured to monocytes by 1alpha,25-dihydroxyvitamin D3. In addition, endomorphins 1 and 2 led to marked potentiation of NF-kappaB binding in THP-1 differentiated to macrophage-like cells. Furthermore, these endomorphins further potentiated LPS-induced NF-kappaB binding. Moreover, they inhibited chemotaxis, phagocytosis of Escherichia coli and PMA-stimulated production of hydrogen peroxide in THP-1 differentiated to macrophage-like cells. These results suggest that endomorphins 1 and 2 may inhibit THP-1 functions, such as cytokine production and functions related to innate immune, and potentiate NF-kappaB DNA binding in THP-1.

  16. Alveolar Macrophage Polarisation in Lung Cancer

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    Saleh A. Almatroodi

    2014-01-01

    Full Text Available The role of alveolar macrophages in lung cancer is multifaceted and conflicting. Alveolar macrophage secretion of proinflammatory cytokines has been found to enhance antitumour functions, cytostasis (inhibition of tumour growth, and cytotoxicity (macrophage-mediated killing. In contrast, protumour functions of alveolar macrophages in lung cancer have also been indicated. Inhibition of antitumour function via secretion of the anti-inflammatory cytokine IL-10 as well as reduced secretion of proinflammatory cytokines and reduction of mannose receptor expression on alveolar macrophages may contribute to lung cancer progression and metastasis. Alveolar macrophages have also been found to contribute to angiogenesis and tumour growth via the secretion of IL-8 and VEGF. This paper reviews the evidence for a dual role of alveolar macrophages in lung cancer progression.

  17. PEDF mediates pathological neovascularization by regulating macrophage recruitment and polarization in the mouse model of oxygen-induced retinopathy

    Science.gov (United States)

    Gao, Sha; Li, Changwei; Zhu, Yanji; Wang, Yanuo; Sui, Ailing; Zhong, Yisheng; Xie, Bing; Shen, Xi

    2017-01-01

    Macrophages have been demonstrated to play a proangiogenic role in retinal pathological vascular growth. Pigment epithelium-derived factor (PEDF) works as a powerful endogenous angiogenesis inhibitor, but its role in macrophage recruitment and polarization is largely unknown. To explore the underlying mechanisms, we first evaluated macrophage polarization in the retinas of the oxygen-induced retinopathy (OIR) mouse model. Compared to that in normal controls, M1- and M2-like macrophages were all abundantly increased in the retinas of OIR mice. In addition, both M1 and M2 subtypes significantly promoted neovascularization in vitro and in vivo. In addition, we found that PEDF inhibited retinal neovascularization by dampening macrophage recruitment and polarization. Furthermore, PEDF inhibited macrophage polarization through adipose triglyceride lipase (ATGL) by regulating the activation of MAPKs and the Notch1 pathway, as we found that the phosphorylation of MAPKs, including p38MAPK, JNK and ERK, as well as the accumulation of Notch1 were essential for hypoxia-induced macrophage polarization, while PEDF significantly dampened M1 subtype-related iNOS and M2 subtype-related Arg-1 expression by inhibiting hypoxia-induced activation of Notch1 and MAPKs through ATGL. These findings reveal a protective role of PEDF against retinal neovascularization by regulating macrophage recruitment and polarization. PMID:28211523

  18. Inhibition of ESAT6 and CFP10 fusion proteins on the autophagosomes formation of macrophages%ESAT6和CFP10融合蛋白抑制巨噬细胞自噬体形成的实验研究

    Institute of Scientific and Technical Information of China (English)

    师长宏; 毛峰峰; 赵勇; 张海; 张彩琴; 白冰; 赵善民

    2011-01-01

    The objective of this study was to study the inhibition of ESAT6 and CFP10 fusion protein on the autophagosomes formation of macrophages. Following the infection with M. tuberculosis H37Rv strains, autophagosomes of macrophages were induced by rapamycin and the effects of ESAT6-CFP10 fusion protein on the autophagosomes formation were observed by transmission electron microscope. Macrophages cellular mRNAs and proteins were extracted and the expression of autophagyrelated genes (atg) was detected by real-time quantitative PCR and immunoblot method respectively. Results demonstrated that macrophages could form autophagosomes by rapamycin inductio, which having scavenging effect on the M. tuberculosis infected cells. ESAT6-CFP10 fusion proteins could inhibit autophagosome formation in macrophages, significantly increase M. tuberculosis colony forming units (CFU) (P<0.05) and decrease the expression of atgs, especially changing atg8 expression level obviously (P<0.05). The result suggested that ESAT6-CFP10 fusion protein could inhibit the formation of autophagosomes and resist phagocytize by regulating the expression level of atg protein.%目的 观察ESAT6和CFP10融合蛋白对感染MTB的巨噬细胞自噬体形成的抑制作用.方法 雷帕霉素诱导小鼠巨噬细胞自噬体形成后,用MTB毒株H37Rv感染巨噬细胞,再用25μg/mL的ESAT6-CFP10融合蛋白作用于巨噬细胞,电镜观察自噬体相成的变化,计数MTB的菌落数.提取巨噬细胞总RNA和蛋白,以RT-PCR和免疫印迹方法检测自噬相关基因(atg)表达水平的变化.结果 ESAT6-CFP10融合蛋白后可抑制巨噬细胞中自噬体的形成,显著提高CFU指数(P<0.05),并导致atg分子表达水平下降,其中atg8表达量下降最为明显(P<0.05).结论 ESAT6和CFP10融合蛋白可通过调控atg表达水平影响巨噬细胞自噬功能.

  19. HIV-1 activates macrophages independent of Toll-like receptors.

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    Joseph N Brown

    Full Text Available BACKGROUND: Macrophages provide an interface between innate and adaptive immunity and are important long-lived reservoirs for Human Immunodeficiency Virus Type-1 (HIV-1. Multiple genetic networks involved in regulating signal transduction cascades and immune responses in macrophages are coordinately modulated by HIV-1 infection. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate complex interrelated processes and to assemble an integrated view of activated signaling networks, a systems biology strategy was applied to genomic and proteomic responses by primary human macrophages over the course of HIV-1 infection. Macrophage responses, including cell cycle, calcium, apoptosis, mitogen-activated protein kinases (MAPK, and cytokines/chemokines, to HIV-1 were temporally regulated, in the absence of cell proliferation. In contrast, Toll-like receptor (TLR pathways remained unaltered by HIV-1, although TLRs 3, 4, 7, and 8 were expressed and responded to ligand stimulation in macrophages. HIV-1 failed to activate phosphorylation of IRAK-1 or IRF-3, modulate intracellular protein levels of Mx1, an interferon-stimulated gene, or stimulate secretion of TNF, IL-1beta, or IL-6. Activation of pathways other than TLR was inadequate to stimulate, via cross-talk mechanisms through molecular hubs, the production of proinflammatory cytokines typical of a TLR response. HIV-1 sensitized macrophage responses to TLR ligands, and the magnitude of viral priming was related to virus replication. CONCLUSIONS/SIGNIFICANCE: HIV-1 induced a primed, proinflammatory state, M1(HIV, which increased the responsiveness of macrophages to TLR ligands. HIV-1 might passively evade pattern recognition, actively inhibit or suppress recognition and signaling, or require dynamic interactions between macrophages and other cells, such as lymphocytes or endothelial cells. HIV-1 evasion of TLR recognition and simultaneous priming of macrophages may represent a strategy for viral survival, contribute

  20. In vivo inhibition of c-MYC in myeloid cells impairs tumor-associated macrophage maturation and pro-tumoral activities.

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    Oscar M Pello

    Full Text Available Although tumor-associated macrophages (TAMs are involved in tumor growth and metastasis, the mechanisms controlling their pro-tumoral activities remain largely unknown. The transcription factor c-MYC has been recently shown to regulate in vitro human macrophage polarization and be expressed in macrophages infiltrating human tumors. In this study, we exploited the predominant expression of LysM in myeloid cells to generate c-Myc(fl/fl LysM(cre/+ mice, which lack c-Myc in macrophages, to investigate the role of macrophage c-MYC expression in cancer. Under steady-state conditions, immune system parameters in c-Myc(fl/fl LysM(cre/+ mice appeared normal, including the abundance of different subsets of bone marrow hematopoietic stem cells, precursors and circulating cells, macrophage density, and immune organ structure. In a model of melanoma, however, TAMs lacking c-Myc displayed a delay in maturation and showed an attenuation of pro-tumoral functions (e.g., reduced expression of VEGF, MMP9, and HIF1α that was associated with impaired tissue remodeling and angiogenesis and limited tumor growth in c-Myc(fl/fl LysM(cre/+ mice. Macrophage c-Myc deletion also diminished fibrosarcoma growth. These data identify c-Myc as a positive regulator of the pro-tumoral program of TAMs and suggest c-Myc inactivation as an attractive target for anti-cancer therapy.

  1. IL4I1 Is a Novel Regulator of M2 Macrophage Polarization That Can Inhibit T Cell Activation via L-Tryptophan and Arginine Depletion and IL-10 Production.

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    Yinpu Yue

    Full Text Available Interleukin 4-induced gene-1 (IL4I1 was initially described as an early IL-4-inducible gene in B cells. IL4I1 protein can inhibit T cell proliferation by releasing its enzymatic catabolite, H2O2, and this effect is associated with transient down-regulation of T cell CD3 receptor-zeta (TCRζ expression. Herein, we show that IL4I1 contributes to the regulation of macrophage programming. We found that expression of IL4I1 increased during bone marrow-derived macrophage (BMDM differentiation, expression of IL4I1 is much higher in primary macrophages than monocytes, and IL4I1 expression in BMDMs could be induced by Th1 and Th2 cytokines in two different patterns. Gene expression analysis revealed that overexpression of IL4I1 drove the expression of M2 markers (Fizz1, Arg1, YM-1, MR and inhibited the expression of M1-associated cytokines. Conversely, knockdown of IL4I1 by siRNA resulted in opposite effects, and also attenuated STAT-3 and STAT-6 phosphorylation. Furthermore, IL4I1 produced by macrophages catalyzed L-tryptophan degradation, while levo-1-methyl-tryptophan (L-1-MT, but not dextro-1-methyl-tryptophan, partially rescued IL4I1-dependent inhibition of T cell activation. Other inhibitors, such as diphenylene iodonium (DPI, an anti-IL-10Rα blocking antibody, and a nitric oxide synthase inhibitor, NG-monomethyl-L-arginine, also had this effect. Overall, our findings indicate that IL4I1 promotes an enhanced M2 functional phenotype, which is most likely associated with the phosphorylation of STAT-6 and STAT-3. Moreover, DPI, L-1-MT, NG-monomethyl-L-arginine, and anti-IL-10Rα blocking antibody were all found to be effective IL4I1 inhibitors in vitro.

  2. Sphingosine kinase-1 (SphK-1 regulates Mycobacterium smegmatis infection in macrophages.

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    Hridayesh Prakash

    Full Text Available Sphingosine kinase-1 is known to mediate Mycobacterium smegmatis induced inflammatory responses in macrophages, but its role in controlling infection has not been reported to date. We aimed to unravel the significance of SphK-1 in controlling M. smegmatis infection in RAW 264.7 macrophages. Our results demonstrated for the first time that selective inhibition of SphK-1 by either D, L threo dihydrosphingosine (DHS; a competitive inhibitor of Sphk-1 or Sphk-1 siRNA rendered RAW macrophages sensitive to M. smegmatis infection. This was due to the reduction in the expression of iNOs, p38, pp-38, late phagosomal marker, LAMP-2 and stabilization of the RelA (pp-65 subunit of NF-kappaB. This led to a reduction in the generation of NO and secretion of TNF-alpha in infected macrophages. Congruently, overexpression of SphK-1 conferred resistance in macrophages to infection which was due to enhancement in the generation of NO and expression of iNOs, pp38 and LAMP-2. In addition, our results also unraveled a novel regulation of p38MAPK by SphK-1 during M. smegmatis infection and generation of NO in macrophages. Enhanced NO generation and expression of iNOs in SphK-1++ infected macrophages demonstrated their M-1(bright phenotype of these macrophages. These findings thus suggested a novel antimycobacterial role of SphK-1 in macrophages.

  3. Sympathetic Nerve Activity Maintains an Anti-Inflammatory State in Adipose Tissue in Male Mice by Inhibiting TNF-α Gene Expression in Macrophages.

    Science.gov (United States)

    Tang, Lijun; Okamoto, Shiki; Shiuchi, Tetsuya; Toda, Chitoku; Takagi, Kazuyo; Sato, Tatsuya; Saito, Kumiko; Yokota, Shigefumi; Minokoshi, Yasuhiko

    2015-10-01

    Adipose tissue macrophages (ATMs) play an important role in the inflammatory response in obese animals. How ATMs are regulated in lean animals has remained elusive, however. We now show that the sympathetic nervous system (SNS) is necessary to maintain the abundance of the mRNA for the proinflammatory cytokine TNF-α at a low level in ATMs of lean mice. Intracerebroventricular injection of agouti-related neuropeptide increased the amount of TNF-α mRNA in epididymal (epi) white adipose tissue (WAT), but not in interscapular brown adipose tissue (BAT), through inhibition of sympathetic nerve activity in epiWAT. The surgical denervation and β-adrenergic antagonist propranolol up-regulated TNF-α mRNA in both epiWAT and BAT in vivo. Signaling by the β2-adrenergic receptor (AR) and protein kinase A down-regulated TNF-α mRNA in epiWAT explants and suppressed lipopolysaccharide-induced up-regulation of TNF-α mRNA in the stromal vascular fraction of this tissue. β-AR-deficient (β-less) mice manifested an increased plasma TNF-α concentration and increased TNF-α mRNA abundance in epiWAT and BAT. TNF-α mRNA abundance was greater in ATMs (CD11b(+) cells of the stromal vascular fraction) from epiWAT or BAT of wild-type mice than in corresponding CD11b(-) cells, and β2-AR mRNA abundance was greater in ATMs than in CD11b(-) cells of epiWAT. Our results show that the SNS and β2-AR-protein kinase A pathway maintain an anti-inflammatory state in ATMs of lean mice in vivo, and that the brain melanocortin pathway plays a role in maintaining this state in WAT of lean mice via the SNS.

  4. Inhibition of DC-SIGN-mediated transmission of human immunodeficiency virus type 1 by Toll-like receptor 3 signalling in breast milk macrophages

    Science.gov (United States)

    Yagi, Yukie; Watanabe, Eri; Watari, Eiji; Shinya, Eiji; Satomi, Misao; Takeshita, Toshiyuki; Takahashi, Hidemi

    2010-01-01

    The majority of cells in early/colostrum milk are breast milk macrophages (BrMMø) expressing dendritic cell (DC)-specific intercellular adhesion molecule 3 (ICAM3) grabbing nonintegrin (DC-SIGN), and the expression level of DC-SIGN on BrMMø will determine cell-to-cell human immunodeficiency virus type 1 (HIV-1) transmissibility. Thus, one of the strategies to prevent vertical transmission of HIV-1 through breast-feeding is to find a way to suppress DC-SIGN expression on BrMMø. As for the expression of Toll-like receptors (TLRs) in BrMMø, TLR3 was always seen in BrMMø but not in peripheral blood monocytes (PBMo). Also, the expression of TLR3 was slightly enhanced in BrMMø when the cells were treated with interleukin (IL)-4. Moreover, when TLR3 was stimulated with its specific ligand, the double-stranded RNA (dsRNA) poly(I:C), DC-SIGN expression on BrMMø was reduced even in the IL-4-mediated enhanced state. Some reduction may be caused by type I interferons (IFNs), such as IFN-α/β, secreted from BrMMø. Indeed, both IFNs, particularly IFN-β, showed a strong capacity to suppress the enhancement of DC-SIGN expression on IL-4-treated BrMMø and such TLR3-mediated DC-SIGN suppression was partially abrogated by the addition of anti-IFN-α/β-receptor-specific antibodies. As expected, DC-SIGN-mediated HIV-1 transmission to CD4-positive cells by BrMMø was inhibited by either poly(I:C) stimulation or by treatment with type I IFNs. These findings suggest a possible strategy for preventing mother-to-child transmission (MTCT) of HIV-1 via breast-feeding through TLR3 signalling. PMID:20406303

  5. Nitration of Tyrosine Residue Y10 of Aβ1-42 Significantly Inhibits Its Aggregation and Cytotoxicity.

    Science.gov (United States)

    Zhao, Jie; Wu, Jinming; Yang, Zhen; Li, Hailing; Gao, Zhonghong

    2017-04-17

    Amyloid-β plaques and oxidative stress are the major hallmarks of Alzheimer's disease. Our previous study found that the heme-Aβ complex enhanced the catalytic effect of free heme on protein tyrosine nitration in the presence of hydrogen peroxide (H2O2) and nitrite (NO2(-)). Y10 in Aβ could be the first target to be nitrated. We also found that nitration of Aβ1-40 significantly decreased its aggregation. However, a contrary report showed that nitration of Aβ1-42 by peroxynitrite enhanced its aggregation. To rule out the interference of peroxynitrite caused Aβ oxidation, we used synthetic Y10 nitrated Aβ1-42 to study the influence of Y10 nitration on Aβ1-42's aggregation and cytotoxicity in this study. We confirmed that Aβ1-42 could be nitrated in the presence of H2O2, NO2(-), and heme by dot blotting. CD spectroscopy showed an increase of β-sheet structure of Aβ1-42 and its mutants. The thioflavin T (ThT) flourescence assay revealed that both nitration and chlorination significantly inhibited Aβ1-42 fibril formation. TEM and AFM observations of Aβ peptide aggregates further confirmed that Y10 modification inhibited Aβ1-42 fibril formation. The cytotoxicity study of native and modified Aβ peptides on SH-SY5Y cells revealed that nitration of Aβ1-42 remarkably decreased the neurotoxicity of Aβ1-42. On the basis of these results, we hypothesized that nitration of Y10 may block the π-π stacking interactions of Aβ1-42 so that it inhibit its aggregation and neurotoxicity. More importantly, considerable evidence suggested that the levels of nitrite plus nitrate significantly decreased in the brain of AD patients. Thus, we believe that these findings would be helpful for further understanding the function of Aβ in AD.

  6. MicroRNA-24 Modulates Staphylococcus aureus-Induced Macrophage Polarization by Suppressing CHI3L1.

    Science.gov (United States)

    Jingjing, Zhang; Nan, Zhang; Wei, Wu; Qinghe, Guo; Weijuan, Wang; Peng, Wang; Xiangpeng, Wang

    2017-03-16

    Macrophages play a crucial role in host innate anti-Staphylococcus aureus defense, which is tightly regulated by multiple factors, including microRNAs. A recent study showed that miR-24 plays an important role in macrophage polarization. Here, we investigated the biological function of miR-24 in S. aureus-stimulated macrophages. The results revealed that miR-24 expression was significantly decreased in both human and mouse macrophage cell lines with S. aureus stimulation in a time-dependent manner. Moreover, miR-24 overexpression significantly decreased the production of M1 phenotype markers, such as IL-6, iNOS, TNF-α, CD86, and CD80, whereas it increased the production of M2 markers, such as Arg1, CCL17, CCL22, CD163, and CD206, in S. aureus-stimulated macrophages. Conversely, knockdown of miR-24 promoted M1 macrophage polarization but diminished M2 macrophage polarization in S. aureus-stimulated macrophages. Furthermore, CHI3L1 was predicted as a target gene of miR-24 using bioinformatics software and identified by luciferase reporter assay. Additionally, miR-24 overexpression inhibited CHI3L1 expression and downregulated the downstream MAPK pathway in S. aureus-stimulated macrophages. Finally, CHI3L1 overexpression rescued macrophage polarization and MAPK pathway inhibition induced by miR-24 mimic transfection in S. aureus-stimulated macrophages. In conclusion, the data suggest that miR-24 serves as a molecular regulator in S. aureus-induced macrophage polarization through targeting of CHI3L1 and regulation of the MAPK pathway, which may provide a promising therapeutic target for S. aureus-related infections and inflammatory diseases.

  7. Apigenin Attenuates Atherogenesis through Inducing Macrophage Apoptosis via Inhibition of AKT Ser473 Phosphorylation and Downregulation of Plasminogen Activator Inhibitor-2

    OpenAIRE

    Ping Zeng; Bin Liu; Qun Wang; Qin Fan; Jian-Xin Diao; Jing Tang; Xiu-Qiong Fu; Xue-Gang Sun

    2015-01-01

    Macrophage survival is believed to be a contributing factor in the development of early atherosclerotic lesions. Dysregulated apoptosis of macrophages is involved in the inflammatory process of atherogenesis. Apigenin is a flavonoid that possesses various clinically relevant properties such as anti-inflammatory, antiplatelet, and antitumor activities. Here we showed that apigenin attenuated atherogenesis in apoE-/- mice in an in vivo test. In vitro experiments suggested that apigenin induced ...

  8. Macrophage Infiltration and Alternative Activation during Wound Healing Promote MEK1-Induced Skin Carcinogenesis.

    Science.gov (United States)

    Weber, Christine; Telerman, Stephanie B; Reimer, Andreas S; Sequeira, Ines; Liakath-Ali, Kifayathullah; Arwert, Esther N; Watt, Fiona M

    2016-02-15

    Macrophages are essential for the progression and maintenance of many cancers, but their role during the earliest stages of tumor formation is unclear. To test this, we used a previously described transgenic mouse model of wound-induced skin tumorigenesis, in which expression of constitutively active MEK1 in differentiating epidermal cells results in chronic inflammation (InvEE mice). Upon wounding, the number of epidermal and dermal monocytes and macrophages increased in wild-type and InvEE skin, but the increase was greater, more rapid, and more sustained in InvEE skin. Macrophage ablation reduced tumor incidence. Furthermore, bioluminescent imaging in live mice to monitor macrophage flux at wound sites revealed that macrophage accumulation was predictive of tumor formation; wounds with the greatest number of macrophages at day 5 went on to develop tumors. Gene expression profiling of flow-sorted monocytes, macrophages, and T cells from InvEE and wild-type skin showed that as wound healing progressed, InvEE macrophages altered their phenotype. Throughout wound healing and after wound closure, InvEE macrophages demonstrated sustained upregulation of several markers implicated in alternative macrophage activation including arginase-1 (ARG1) and mannose receptor (CD206). Notably, inhibition of ARG1 activity significantly reduced tumor formation and epidermal proliferation in vivo, whereas addition of L-arginase to cultured keratinocytes stimulated proliferation. We conclude that macrophages play a key role in early, inflammation-mediated skin tumorigenesis, with mechanistic evidence suggesting that ARG1 secretion drives tumor development by stimulating epidermal cell proliferation. These findings highlight the importance of cancer immunotherapies aiming to polarize tumor-associated macrophages toward an antitumor phenotype.

  9. Macrophage CGI-58 Attenuates Inflammatory Responsiveness via Promotion of PPARγ Signaling

    Directory of Open Access Journals (Sweden)

    Dan Yang

    2016-02-01

    Full Text Available Background/Aims: Comparative gene identification-58 (CGI-58, an adipose triglyceride lipase (ATGL coactivator, strongly promotes ATGL-mediated triglyceride (TG catabolism. Beyond its function in promoting lipolysis, other features of CGI-58 have been proposed. Here, we investigated the role of CGI-58 in the regulation of inflammatory responsiveness in macrophages. Methods: Macrophage-specific GCI-58 transgenic mice (TG and wild type mice (WT were fed a high fat diet (HFD, and RAW264.7 cells were treated with lipopolysaccharide (LPS. The peroxisome proliferator-activated receptor (PPAR signaling was detected. The inflammatory responsiveness and mitochondrial function were examined. Results: TG mice showed lower serum levels of proinflammatory cytokines and better mitochondrial function in macrophages compared with WT control. Knockdown of CGI-58 in RAW264.7 cells aggravated LPS-induced inflammation and mitochondrial dysfunction. CGI-58 overexpression and silencing in macrophages induced and inhibited PPARγ expression and activity, respectively. Most importantly, the PPARγ-specific agonist rosiglitazone significantly suppressed inflammation and mitochondrial dysfunction induced by CGI-58 deficiency. Furthermore, knockdown of PPARγ in macrophages significantly dampened the role of CGI-58 in suppression of inflammation and mitochondrial dysfunction. Interestingly, CGI-58 inhibited histone deacetylation and the recruitment of histone deacetylase (HDAC to the PPARγ promoter. Finally, ATGL deficiency did not affect inflammatory responsiveness and PPARγ signaling in macrophages. Conclusion: These results demonstrate that macrophage CGI-58 enhances PPARγ signaling and thus suppresses inflammatory responsiveness and mitochondrial dysfunction.

  10. Fenretinide inhibits macrophage inflammatory mediators and controls hypertension in spontaneously hypertensive rats via the peroxisome proliferator-activated receptor gamma pathway

    Directory of Open Access Journals (Sweden)

    Lin CH

    2016-11-01

    significantly decreased blood pressure. Taken together, these results indicate that fenretinide might be a potent antihypertensive agent that works by suppressing inflammation via activating PPARγ. Keywords: fenretinide, hypertension, inflammation, macrophage, peroxisome proliferator-activated receptor γ

  11. Marine organism sulfated polysaccharides exhibiting significant antimalarial activity and inhibition of red blood cell invasion by Plasmodium.

    Science.gov (United States)

    Marques, Joana; Vilanova, Eduardo; Mourão, Paulo A S; Fernàndez-Busquets, Xavier

    2016-04-13

    The antimalarial activity of heparin, against which there are no resistances known, has not been therapeutically exploited due to its potent anticoagulating activity. Here, we have explored the antiplasmodial capacity of heparin-like sulfated polysaccharides from the sea cucumbers Ludwigothurea grisea and Isostichopus badionotus, from the red alga Botryocladia occidentalis, and from the marine sponge Desmapsamma anchorata. In vitro experiments demonstrated for most compounds significant inhibition of Plasmodium falciparum growth at low-anticoagulant concentrations. This activity was found to operate through inhibition of erythrocyte invasion by Plasmodium, likely mediated by a coating of the parasite similar to that observed for heparin. In vivo four-day suppressive tests showed that several of the sulfated polysaccharides improved the survival of Plasmodium yoelii-infected mice. In one animal treated with I. badionotus fucan parasitemia was reduced from 10.4% to undetectable levels, and Western blot analysis revealed the presence of antibodies against P. yoelii antigens in its plasma. The retarded invasion mediated by sulfated polysaccharides, and the ensuing prolonged exposure of Plasmodium to the immune system, can be explored for the design of new therapeutic approaches against malaria where heparin-related polysaccharides of low anticoagulating activity could play a dual role as drugs and as potentiators of immune responses.

  12. Marine organism sulfated polysaccharides exhibiting significant antimalarial activity and inhibition of red blood cell invasion by Plasmodium

    Science.gov (United States)

    Marques, Joana; Vilanova, Eduardo; Mourão, Paulo A. S.; Fernàndez-Busquets, Xavier

    2016-01-01

    The antimalarial activity of heparin, against which there are no resistances known, has not been therapeutically exploited due to its potent anticoagulating activity. Here, we have explored the antiplasmodial capacity of heparin-like sulfated polysaccharides from the sea cucumbers Ludwigothurea grisea and Isostichopus badionotus, from the red alga Botryocladia occidentalis, and from the marine sponge Desmapsamma anchorata. In vitro experiments demonstrated for most compounds significant inhibition of Plasmodium falciparum growth at low-anticoagulant concentrations. This activity was found to operate through inhibition of erythrocyte invasion by Plasmodium, likely mediated by a coating of the parasite similar to that observed for heparin. In vivo four-day suppressive tests showed that several of the sulfated polysaccharides improved the survival of Plasmodium yoelii-infected mice. In one animal treated with I. badionotus fucan parasitemia was reduced from 10.4% to undetectable levels, and Western blot analysis revealed the presence of antibodies against P. yoelii antigens in its plasma. The retarded invasion mediated by sulfated polysaccharides, and the ensuing prolonged exposure of Plasmodium to the immune system, can be explored for the design of new therapeutic approaches against malaria where heparin-related polysaccharides of low anticoagulating activity could play a dual role as drugs and as potentiators of immune responses. PMID:27071342

  13. Clodronate inhibits tumor angiogenesis in mouse models of ovarian cancer

    Science.gov (United States)

    Reusser, Nicole M; Dalton, Heather J; Pradeep, Sunila; Gonzalez-Villasana, Vianey; Jennings, Nicholas B; Vasquez, Hernan G; Wen, Yunfei; Rupaimoole, Rajesh; Nagaraja, Archana S; Gharpure, Kshipra; Miyake, Takahito; Huang, Jie; Hu, Wei; Lopez-Berestein, Gabriel; Sood, Anil K

    2014-01-01

    Purpose Bisphosphonates have been shown to inhibit and deplete macrophages. The effects of bisphosphonates on other cell types in the tumor microenvironment have been insufficiently studied. Here, we sought to determine the effects of bisphosphonates on ovarian cancer angiogenesis and growth via their effect on the microenvironment, including macrophage, endothelial and tumor cell populations. Experimental Design Using in vitro and in vivo models, we examined the effects of clodronate on angiogenesis and macrophage density, and the overall effect of clodronate on tumor size and metastasis. Results Clodronate inhibited the secretion of pro-angiogenic cytokines by endothelial cells and macrophages, and decreased endothelial migration and capillary tube formation. In treated mice, clodronate significantly decreased tumor size, number of tumor nodules, number of tumor-associated macrophages and tumor capillary density. Conclusions Clodronate is a potent inhibitor of tumor angiogenesis. These results highlight clodronate as a potential therapeutic for cancer. PMID:24841852

  14. Anti-Inflammatory Effect of Spirulina platensis in Macrophages Is Beneficial for Adipocyte Differentiation and Maturation by Inhibiting Nuclear Factor-κB Pathway in 3T3-L1 Adipocytes.

    Science.gov (United States)

    Pham, Tho X; Lee, Ji-Young

    2016-06-01

    We previously showed that the organic extract of a blue-green alga, Spirulina platensis (SPE), had potent anti-inflammatory effects in macrophages. As the interplay between macrophages and adipocytes is critical for adipocyte functions, we investigated the contribution of the anti-inflammatory effects of SPE in macrophages to adipogenesis/lipogenesis in 3T3-L1 adipocytes. 3T3-L1 preadipocytes were treated with 10% conditioned medium from lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages (CMC) or LPS-stimulated, but SPE-pretreated, macrophages (CMS) at different stages of adipocyte differentiation. The expression of adipocyte differentiation markers, such as CCAAT/enhancer-binding protein α, peroxisome proliferator-activated receptor γ, and perilipin, was significantly repressed by CMC when added on day 3, while the repression was attenuated by CMS. Oil Red O staining confirmed that adipocyte maturation in CMS-treated cells, but not in CMC-treated cells, was equivalent to that of control cells. Nuclear translocation of nuclear factor κB (NF-κB) p65 was decreased by CMS compared to CMC. In lipid-laden adipocytes, CMC promoted the loss of lipid droplets, while CMS had minimal effects. Histone deacetylase 9 mRNA and protein levels were increased during adipocyte maturation, which were decreased by CMC. In conclusion, by cross-talking with adipocytes, the anti-inflammatory effects of SPE in macrophages promoted adipocyte differentiation/maturation, at least in part, by repressing the activation of NF-κB inflammatory pathways, which otherwise can be compromised in inflammatory conditions.

  15. Compound FLZ inhibits lipopolysaccharide-induced inflammatory effects via down-regulation of the TAK-IKK and TAK-JNK/ p38MAPK pathways in RAW264.7 macrophages

    Institute of Scientific and Technical Information of China (English)

    Hongyan PANG; Gang LIU; Gengtao LIU

    2009-01-01

    Aim:The aim of this study was to investigate the effect of the squamosamide derivative FLZ (N-2-(4-hydroxy-phenyl)-ethyl-2-(2,5-dimethoxy-phenyl)-3-(3-methoxy-4-hydroxy-phenyl)-acrylamide) on.lipopolysaccharide (LPS)-induced inflam-matory mediator production and the underlying mechanism in RAW264.7 macrophages.Methods: RAW264.7 cells were preincubated with non-toxic concentrations of compound FLZ (1,5,and 10 μmol/L) for 30 min and then stimulated with 10 μg/L LPS.The production of nitric oxide (NO),the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2),and the activation of nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways were examined.Results: FLZ significantly inhibited the LPS-induced production of NO,as well as the expression of iNOS and COX-2 at both the RNA and the protein levels in RAW264.7 cells.The LPS-induced increase in the DNA binding activity of NF-κBand activator protein I (AP-1),the nuclear translocation of NF-κB p65,the degradation of the inhibitory κBα protein (IκBα)and the phosphorylation of IκBα,IκB kinase (IKK) α/β,c-Jun NH2-terminal kinase (JNK) and p38 MAPKs were all sup-pressed by FLZ.However,the phosphorylation of extracellular signal-regulated kinase (ERK) was not affected.Further study revealed that FLZ inhibited the phosphorylation of transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1),which is an upstream signaling molecule required for IKKα/β,JNK and p38 activation.Conclusion: FLZ inhibited the LPS-induced production of inflammatory mediators at least partly through the downregula-tion of the TAK-IKK and TAK-JNK/p38MAPK pathways.

  16. Study on the mechanism of macrophages inhibiting epithelial ovarian cancer cell metas-tasis induced by TWEAK via exosomes%TWEAK通过外泌体途径介导巨噬细胞抑制上皮性卵巢癌细胞转移的研究

    Institute of Scientific and Technical Information of China (English)

    胡媛; 邱丽华

    2015-01-01

    Objective:To investagate the mechanism of macrophages inhibiting ovarian cancer cell metastasis induced by TWEAK via exosomes. Methods:Macrophages, which were differentiated from THP-1 by PMA,were stimulated by TWEAK for 24h. Exosomes were isolated from macrophages ' conditioned medium by exosome isolation kit and then were detected by transmission electron microscopy. The ovarian cancer cell lines SKOV3 and HO-8910pm were separately cocultured with PBS,exosomes secreted by macrophages and exosomes secreted by TWEAK-treated-macrophages for 48h,and then were detected the ability of migration and inva-sion by using transwell methods. Results:Exosomes purified from macrophages ' conditioned media exhibited round morphology by electron microscopy and a size range of 30 to 100nm. Compared with the blank group,the ability of migration and invasion of ovarian cancer cells,si-tumulated by exosomes secreted by macrophages,was significantly increased (P<0. 05). How-ever,once treated by TWEAK,the macrophages reduced the ability of migration and invasion of ovarian cancer cells via its secreted exosomes. Conclusions:TWEAK could reverse the ability of macrophages to promote ovarian cancer cell metastasis via exosomes.%目的::探讨TWEAK能否通过外泌体途径介导巨噬细胞对上皮性卵巢癌细胞转移的调控。方法:佛波酯诱导人单核细胞系THP-1为贴壁的巨噬细胞,TWEAK刺激巨噬细胞24 h后抽提外泌体,透射电镜观察其形态;分别将PBS、巨噬细胞分泌的外泌体、TWEAK刺激后巨噬细胞分泌的外泌体与上皮性卵巢癌细胞系SKOV3、HO-8910 pm共培养,48 h后通过Transwell实验检测其迁移、侵袭能力。结果:透射电镜可见巨噬细胞分泌的外泌体呈圆形,直径30~100 nm。 Transwell实验显示,与空白对照组相比,巨噬细胞分泌的外泌体可使上皮性卵巢癌细胞的迁移和侵袭能力增高;而TWEAK刺激巨噬细胞后,其分泌的外泌体则可降低其迁移和

  17. MAP kinase phosphatase 2 regulates macrophage-adipocyte interaction.

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    Huipeng Jiao

    Full Text Available Inflammation is critical for the development of obesity-associated metabolic disorders. This study aims to investigate the role of mitogen-activated protein kinase phosphatase 2 (MKP-2 in inflammation during macrophage-adipocyte interaction.White adipose tissues (WAT from mice either on a high-fat diet (HFD or normal chow (NC were isolated to examine the expression of MKP-2. Murine macrophage cell line RAW264.7 stably expressing MKP-2 was used to study the regulation of MKP-2 in macrophages in response to saturated free fatty acid (FFA and its role in macrophage M1/M2 activation. Macrophage-adipocyte co-culture system was employed to investigate the role of MKP-2 in regulating inflammation during adipocyte-macrophage interaction. c-Jun N-terminal kinase (JNK- and p38-specific inhibitors were used to examine the mechanisms by which MKP-2 regulates macrophage activation and macrophage-adipocytes interaction.HFD changed the expression of MKP-2 in WAT, and MKP-2 was highly expressed in the stromal vascular cells (SVCs. MKP-2 inhibited the production of proinflammatory cytokines in response to FFA stimulation in macrophages. MKP-2 inhibited macrophage M1 activation through JNK and p38. In addition, overexpression of MKP-2 in macrophages suppressed inflammation during macrophage-adipocyte interaction.MKP-2 is a negative regulator of macrophage M1 activation through JNK and p38 and inhibits inflammation during macrophage-adipocyte interaction.

  18. Anti-Inflammatory Effect of Methylpenicinoline from a Marine Isolate of Penicillium sp. (SF-5995: Inhibition of NF-κB and MAPK Pathways in Lipopolysaccharide-Induced RAW264.7 Macrophages and BV2 Microglia

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    Dong-Cheol Kim

    2014-11-01

    Full Text Available In the course of a search for anti-inflammatory metabolites from marine-derived fungi, methylpenicinoline (1 was isolated from a marine isolate of Penicillin sp. Compound 1 inhibited lipopolysaccharide (LPS-stimulated nitric oxide (NO production by suppressing the expression of inducible NO synthase (iNOS in RAW264.7 macrophages and BV2 microglia. It also attenuated prostaglandin E2 (PGE2 production by suppressing cyclooxygenase-2 (COX-2 expression in a concentration-dependent manner (from 10 μM to 80 μM without affecting cell viability. In addition, compound 1 reduced the production of the pro-inflammatory cytokine interleukin-1β (IL-1β. In a further study designed to elucidate the mechanism of its anti-inflammatory effects, compound 1 was shown to block nuclear factor-kappa B (NF-κB activation in LPS-induced RAW264.7 macrophages and BV2 microglia by inhibiting the phosphorylation of inhibitor kappa B-α (IκB-α, thereby suppressing the nuclear translocation of NF-κB dimers, namely p50 and p65, that are known to be crucial molecules associated with iNOS and COX-2 expression. In addition, compound 1 inhibited the activation of mitogen-activated protein kinase (MAPK pathways. Taken together, the results suggest that compound 1 might be a valuable therapeutic agent for the treatment of anti-inflammatory and anti-neuroinflammatory diseases.

  19. Metformin Inhibits the Production of Reactive Oxygen Species from NADH:Ubiquinone Oxidoreductase to Limit Induction of Interleukin-1β (IL-1β) and Boosts Interleukin-10 (IL-10) in Lipopolysaccharide (LPS)-activated Macrophages.

    Science.gov (United States)

    Kelly, Beth; Tannahill, Gillian M; Murphy, Michael P; O'Neill, Luke A J

    2015-08-14

    Metformin, a frontline treatment for type II diabetes mellitus, decreases production of the pro-form of the inflammatory cytokine IL-1β in response to LPS in macrophages. We found that it specifically inhibited pro-IL-1β production, having no effect on TNF-α. Furthermore, metformin boosted induction of the anti-inflammatory cytokine IL-10 in response to LPS. We ruled out a role for AMP-activated protein kinase (AMPK) in the effect of metformin because activation of AMPK with A769662 did not mimic metformin here. Furthermore, metformin was still inhibitory in AMKPα1- or AMPKβ1-deficient cells. The activity of NADH:ubiquinone oxidoreductase (complex I) was inhibited by metformin. Another complex I inhibitor, rotenone, mimicked the effect of metformin on pro-IL-1β and IL-10. LPS induced reactive oxygen species production, an effect inhibited by metformin or rotenone pretreatment. MitoQ, a mitochondrially targeted antioxidant, decreased LPS-induced IL-1β without affecting TNF-α. These results, therefore, implicate complex I in LPS action in macrophages.

  20. Endogenous epoxygenases are modulators of monocyte/macrophage activity.

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    Jonas Bystrom

    Full Text Available BACKGROUND: Arachidonic acid is metabolized through three major metabolic pathways, the cyclooxygenase, lipoxygenase and CYP450 enzyme systems. Unlike cyclooxygenase and lipoxygenases, the role of CYP450 epoxygenases in monocyte/macrophage-mediated responses is not known. METHODOLOGY/PRINCIPAL FINDINGS: When transfected in vitro, CYP2J2 is an efficient activator of anti-inflammatory pathways through the nuclear receptor peroxisome proliferator-activated receptor (PPAR α. Human monocytes and macrophages contain PPARα and here we show they express the epoxygenases CYP2J2 and CYP2C8. Inhibition of constitutive monocyte epoxygenases using the epoxygenase inhibitor SKF525A induces cyclooxygenase (COX-2 expression and activity, and the release of TNFα, and can be reversed by either add back of the endogenous epoxygenase products and PPARα ligand 11,12- epoxyeicosatrienoic acid (EET or the addition of the selective synthetic PPARα ligand GW7647. In alternatively activated (IL-4-treated monocytes, in contrast to classically activated cells, epoxygenase inhibition decreased TNFα release. Epoxygenases can be pro-inflammatory via superoxide anion production. The suppression of TNFα by SKF525A in the presence of IL-4 was associated with a reduction in superoxide anion generation and reproduced by the superoxide dismutase MnCl(2. Similar to these acute activation studies, in monocyte derived macrophages, epoxygenase inhibition elevates M1 macrophage TNFα mRNA and further decreases M2 macrophage TNFα. CONCLUSIONS/SIGNIFICANCE: In conclusion, epoxygenase activity represents an important endogenous pathway which limits monocyte activation. Moreover endogenous epoxygenases are immuno-modulators regulating monocyte/macrophage activation depending on the underlying activation state.

  1. Gc protein-derived macrophage-activating factor (GcMAF) stimulates cAMP formation in human mononuclear cells and inhibits angiogenesis in chick embryo chorionallantoic membrane assay

    OpenAIRE

    2010-01-01

    Abstract: The effects of Gc protein-derived macrophage-activating factor (GcMAF) have been studied in cancer and other conditions where angiogenesis is deregulated. In this study, we demonstrate for the first time that the mitogenic response of human peripheral blood mononuclear cells (PBMCs) to GcMAF was associated with 3'-5'-cyclic adenosine monophosphate (cAMP) formation. The effect was dose dependent, and maximal stimulation was achieved using 0.1 ng/ml. Heparin inhibited the stimulatory ...

  2. Citrus unshiu flower inhibits LPS-induced iNOS and COX-2 via MAPKs in RAW 264.7 macrophage cells

    OpenAIRE

    2015-01-01

    In the present study, we investigated the effects of Citrus unshiu flower on regulatory mechanisms of cytokines and nitric oxide (NO) involved in immunological activity of RAW 264.7 macrophages. Our results indicated that ethyl acetate fraction of Citrus unshiu flower (CUF-EA) downregulated LPS-induced nitric oxide (NO) synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, thereby reducing the production of NO and prostaglandin E2 (PGE2) in LPS-activated RAW 264.7 macrophages. Furthermore,...

  3. Soluble Siglec-9 suppresses arthritis in a collagen-induced arthritis mouse model and inhibits M1 activation of RAW264.7 macrophages

    OpenAIRE

    Matsumoto, Takuya; Takahashi, Nobunori; Kojima, Toshihisa; Yoshioka, Yutaka; Ishikawa, Jun; Furukawa, Koichi; Ono, Kenji; Sawada, Makoto; ISHIGURO, NAOKI; Yamamoto, Akihito

    2016-01-01

    Background The aim of this study was to assess the effects of soluble sialic acid-binding immunoglobulin-type lectin (sSiglec)-9 on joint inflammation and destruction in a murine collagen-induced arthritis (CIA) model and in monolayer cultures of murine macrophages (RAW264.7 cells and peritoneal macrophages) and fibroblast-like synoviocytes (FLS) derived from patients with rheumatoid arthritis. Methods DBA/1J mice were immunized with type II collagen. Effects of sSiglec-9 were evaluated using...

  4. Neisseria gonorrhoeae survives within and modulates apoptosis and inflammatory cytokine production of human macrophages.

    Science.gov (United States)

    Château, Alice; Seifert, H Steven

    2016-04-01

    The human-adapted organism Neisseria gonorrhoeae is the causative agent of gonorrhoea, a sexually transmitted infection. It readily colonizes the genital, rectal and nasalpharyngeal mucosa during infection. While it is well established that N. gonorrhoeae recruits and modulates the functions of polymorphonuclear leukocytes during infection, how N. gonorrhoeae interacts with macrophages present in infected tissue is not fully defined. We studied the interactions of N. gonorrhoeae with two human monocytic cell lines, THP-1 and U937, and primary monocytes, all differentiated into macrophages. Most engulfed bacteria were killed in the phagolysosome, but a subset of bacteria was able to survive and replicate inside the macrophages suggesting that those cells may be an unexplored cellular reservoir for N. gonorrhoeae during infection. N. gonorrhoeae was able to modulate macrophage apoptosis: N. gonorrhoeae induced apoptosis in THP-1 cells whereas it inhibited induced apoptosis in U937 cells and primary human macrophages. Furthermore, N. gonorrhoeae induced expression of inflammatory cytokines in macrophages, suggesting a role for macrophages in recruiting polymorphonuclear leukocytes to the site of infection. These results indicate macrophages may serve as a significant replicative niche for N. gonorrhoeae and play an important role in gonorrheal pathogenesis.

  5. Microvesicles secreted by macrophages shuttle invasion-potentiating microRNAs into breast cancer cells

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    Lin Ling

    2011-09-01

    Full Text Available Abstract Background Tumor-associated macrophages (TAMs are alternatively activated cells induced by interleukin-4 (IL-4-releasing CD4+ T cells. TAMs promote breast cancer invasion and metastasis; however, the mechanisms underlying these interactions between macrophages and tumor cells that lead to cancer metastasis remain elusive. Previous studies have found microRNAs (miRNAs circulating in the peripheral blood and have identified microvesicles, or exosomes, as mediators of cell-cell communication. Therefore, one alternative mechanism for the promotion of breast cancer cell invasion by TAMs may be through macrophage-secreted exosomes, which would deliver invasion-potentiating miRNAs to breast cancer cells. Results We utilized a co-culture system with IL-4-activated macrophages and breast cancer cells to verify that miRNAs are transported from macrophages to breast cancer cells. The shuttling of fluorescently-labeled exogenous miRNAs from IL-4-activated macrophages to co-cultivated breast cancer cells without direct cell-cell contact was observed. miR-223, a miRNA specific for IL-4-activated macrophages, was detected within the exosomes released by macrophages and was significantly elevated in the co-cultivated SKBR3 and MDA-MB-231 cells. The invasiveness of the co-cultivated breast cancer cells decreased when the IL-4-activated macrophages were treated with a miR-223 antisense oligonucleotide (ASO that would inhibit miR-223 expression. Furthermore, results from a functional assay revealed that miR-223 promoted the invasion of breast cancer cells via the Mef2c-β-catenin pathway. Conclusions We conclude that macrophages regulate the invasiveness of breast cancer cells through exosome-mediated delivery of oncogenic miRNAs. Our data provide insight into the mechanisms underlying the metastasis-promoting interactions between macrophages and breast cancer cells.

  6. Genkwanin inhibits proinflammatory mediators mainly through the regulation of miR-101/MKP-1/MAPK pathway in LPS-activated macrophages.

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    Yuan Gao

    Full Text Available Genkwanin is one of the major non-glycosylated flavonoids in many herbs with anti-inflammatory activities. Although its anti-inflammatory activity in vivo has been reported, the potential molecular mechanisms remain obscure. In this study, by pharmacological and genetic approaches, we explore the anti-inflammatory effects of genkwanin in LPS-activated RAW264.7 macrophages. Genkwanin potently decreases the proinflammatory mediators, such as iNOS, TNF-α, IL-1β and IL-6, at the transcriptional and translational levels without cytotoxicity, indicating the excellent anti-inflammatory potency of genkwanin in vitro. Mechanism study shows that genkwanin significantly suppresses the p38- and JNK-mediated AP-1 signaling pathway and increases the mitogen-activated protein kinase (MAPK phosphatase 1 (MKP-1 expression at the posttranscriptional level. We also confirmed that microRNA-101 (miR-101 is a negative regulator of MKP-1 expression. Moreover, regardless of miR-101-deficient cells or miR-101-abundant cells, the suppression effects of genkwanin on supernatant proinflammatory mediators' levels are far less than that in respective negative control cells, suggesting that genkwanin exerts anti-inflammatory effect mainly through reducing miR-101 production. However, genkwanin can't affect the level of phospho-Akt (p-Akt, indicating that the phosphorylation of Akt may be not responsible for the effect of genkwanin on miR-101 production. We conclude that genkwanin exerts its anti-inflammatory effect mainly through the regulation of the miR-101/MKP-1/MAPK pathway.

  7. Inhibition of NF-kB 1 (NF-kBp50 by RNA interference in chicken macrophage HD11 cell line challenged with Salmonella enteritidis

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    Hsin-I Chiang

    2009-01-01

    Full Text Available The NF-kB pathway plays an important role in regulating the immunity response in animals. In this study, small interfering RNAs (siRNA were used to specifically inhibit NF-kB 1 expression and to elucidate the role of NF-kB in the signal transduction pathway of the Salmonella challenge in the chicken HD11 cell line. The cells were transfected with either NF-kB 1 siRNA, glyceraldehyde 3-phosphate dehydrogenase siRNA (positive control or the negative control siRNA for 24 h, followed by Salmonella enteritidis (SE challenge or non-challenge for 1 h and 4 h. Eight candidate genes related to the signal pathway of SE challenge were selected to examine the effect of NF-kB 1 inhibition on their expressions by mRNA quantification. The results showed that, with a 36% inhibition of NF-kB 1 expression, gene expression of both Toll-like receptor (TLR 4 and interleukin (IL-6 was consistently and significantly increased at both 1 h and 4 h following SE challenge, whereas the gene expression of MyD88 and IL-1β was increased at 1 h and 4 h, respectively. These findings suggest a likely inhibitory regulation by NF-kB 1, and could lay the foundation for studying the gene network of the innate immune response of SE infection in chickens.

  8. Inhibition of the nuclear factor kappa B (NF-kappa B) pathway by tetracyclic kaurene diterpenes in macrophages. Specific effects on NF-kappa B-inducing kinase activity and on the coordinate activation of ERK and p38 MAPK.

    Science.gov (United States)

    Castrillo, A; de Las Heras, B; Hortelano, S; Rodriguez, B; Villar, A; Bosca, L

    2001-05-11

    The anti-inflammatory action of most terpenes has been explained in terms of the inhibition of nuclear factor kappaB (NF-kappaB) activity. Ent-kaurene diterpenes are intermediates of the synthesis of gibberellins and inhibit the expression of NO synthase-2 and the release of tumor necrosis factor-alpha in J774 macrophages challenged with lipopolysaccharide. These diterpenes inhibit NF-kappaB and IkappaB kinase (IKK) activation in vivo but failed to affect in vitro the function of NF-kappaB, the phosphorylation and targeting of IkappaBalpha, and the activity of IKK-2. Transient expression of NF-kappaB-inducing kinase (NIK) activated the IKK complex and NF-kappaB, a process that was inhibited by kaurenes, indicating that the inhibition of NIK was one of the targets of these diterpenes. These results show that kaurenes impair the inflammatory signaling by inhibiting NIK, a member of the MAPK kinase superfamily that interacts with tumor necrosis factor receptor-associated factors, and mediate the activation of NF-kappaB by these receptors. Moreover, kaurenes delayed the phosphorylation of p38, ERK1, and ERK2 MAPKs, but not that of JNK, in response to lipopolysaccharide treatment of J774 cells. The absence of a coordinate activation of MAPK and IKK might contribute to a deficient activation of NF-kappaB that is involved in the anti-inflammatory activity of these molecules.

  9. Blueberries reduce pro-inflammatory cytokine TNF-alpha and IL-6 production in mouse macrophages by inhibiting NF Kappa B activation and the MAPK pathway

    Science.gov (United States)

    Blueberries (BB) have been reported to attenuate atherosclerosis in apoE deficient (ApoE-/-) mice. The aim of this study was to evaluate the effects of BB in reducing pro-inflammatory cytokine production in mouse macrophages. ApoE-/- mice were fed AIN-93G diet (CD) or CD formulated to contain 1% fre...

  10. Oval cell response is attenuated by depletion of liver resident macrophages in the 2-AAF/partial hepatectomy rat.

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    Shuai Xiang

    Full Text Available BACKGROUND/AIMS: Macrophages are known to play an important role in hepatocyte mediated liver regeneration by secreting inflammatory mediators. However, there is little information available on the role of resident macrophages in oval cell mediated liver regeneration. In the present study we aimed to investigate the role of macrophages in oval cell expansion induced by 2-acetylaminofluorene/partial hepatectomy (2-AAF/PH in rats. METHODOLOGY/PRINCIPAL FINDINGS: We depleted macrophages in the liver of 2-AAF/PH treated rats by injecting liposome encapsulated clodronate 48 hours before PH. Regeneration of remnant liver mass, as well as proliferation and differentiation of oval cells were measured. We found that macrophage-depleted rats suffered higher mortality and liver transaminase levels. We also showed that depletion of macrophages yielded a significant decrease of EPCAM and PCK positive oval cells in immunohistochemical stained liver sections 9 days after PH. Meanwhile, oval cell differentiation was also attenuated as a result of macrophage depletion, as large foci of small basophilic hepatocytes were observed by day 9 following hepatectomy in control rats whereas they were almost absent in macrophage depleted rats. Accordingly, real-time polymerase chain reaction analysis showed lower expression of albumin mRNA in macrophage depleted livers. Then we assessed whether macrophage depletion may affect hepatic production of stimulating cytokines for liver regeneration. We showed that macrophage-depletion significantly inhibited hepatic expression of tumor necrosis factor-α and interleukin-6, along with a lack of signal transducer and activator of transcription 3 phosphorylation during the early period following hepatectomy. CONCLUSIONS: These data indicate that macrophages play an important role in oval cell mediated liver regeneration in the 2-AAF/PH model.

  11. Anti-inflammatory effects of galangin on lipopolysaccharide-activated macrophages via ERK and NF-κB pathway regulation.

    Science.gov (United States)

    Jung, Yun Chan; Kim, Mi Eun; Yoon, Ju Hwa; Park, Pu Reum; Youn, Hwa-Young; Lee, Hee-Woo; Lee, Jun Sik

    2014-12-01

    Inflammation is the major symptom of the innate immune response to microbial infection. Macrophages, immune response-related cells, play a role in the inflammatory response. Galangin is a member of the flavonols and is found in Alpinia officinarum, galangal root and propolis. Previous studies have demonstrated that galangin has antioxidant, anticancer, and antineoplastic activities. However, the anti-inflammatory effects of galangin are still unknown. In this study, we investigated the anti-inflammatory effects of galangin on RAW 264.7 murine macrophages. Galagin was not cytotoxic to RAW 264.7 cells, and nitric oxide (NO) production induced by lipopolysaccharide (LPS)-stimulated macrophages was significantly decreased by the addition of 50 μM galangin. Moreover, galangin treatment reduced mRNA levels of cytokines, including IL-1β and IL-6, and proinflammatory genes, such as iNOS in LPS-activated macrophages in a dose-dependent manner. Galangin treatment also decreased the protein expression levels of iNOS in activated macrophages. Galangin was found to elicit anti-inflammatory effects by inhibiting ERK and NF-κB-p65 phosphorylation. In addition, galangin-inhibited IL-1β production in LPS-activated macrophages. These results suggest that galangin elicits anti-inflammatory effects on LPS-activated macrophages via the inhibition of ERK, NF-κB-p65 and proinflammatory gene expression.

  12. Soluble factor from murine bladder tumor-2 cell elevates nitric oxide production in macrophages and enhances the taxol-mediated macrophage cytotoxicity on tumor cells.

    Science.gov (United States)

    Choi, Suck-Chei; Oh, Hyun-Mee; Park, Jae-Sung; Han, Weon-Cheol; Yoon, Kwon-Ha; Kim, Tae-Hyeon; Yun, Ki-Jung; Kim, Eun-Cheol; Nah, Yong-Ho; Cha, Young-Nam; Chung, Hun-Taeg; Jun, Chang-Duk

    2003-01-01

    The therapeutic mechanism of taxol is believed to reside primarily in its ability to stabilize microtubules and prevent cell progression through mitosis. Taxol also can activate macrophage-mediated antitumor mechanism through a nitric oxide (NO)-dependent pathway. To address whether any mechanisms account for superficial urinary bladder tumor cell killing, we evaluated the effects of taxol on the growth and viability of murine bladder tumor-2 (MBT-2) cells in vitro, both in the absence and presence of murine macrophages. In addition, we evaluated whether a soluble factor generated from MBT-2 cells could modulate the antitumor activity of the taxol-activated macrophages. Although taxol inhibited the growth of MBT-2 cells, it did not kill the tumor cells. However, preincubation of macrophages with taxol significantly decreased the viability of MBT-2 cells. Secretion of NO correlated with MBT-2 cell killing, and the activated macrophages failed to kill tumor cell targets in the presence of NG-monomethyl-L-arginine, a competitive inhibitor of NO synthase. By the co-culture of macrophages and MBT-2 cells, untreated macrophages also released modest amount of NO and this was synergistically augmented by the treatment with taxol, indicating that MBT-2 tumor cells released some unknown factor that activated the macrophages and enhanced NO production. We named this factor the tumor-derived macrophage activating factor (TMAF). The TMAF-mediated activation of macrophages to enhance the NO production was not blocked by treatment of macrophages with oxidized low-density lipoprotein (Ox-LDL), implying that the scavenger receptor of macrophages is not involved. Sodium nitroprusside (SNP), an NO donor given to the MBT-2 cells, increased the activities of c-Jun N-terminal kinase and caspase-3 in MBT-2 cells and associated with nucleosomal fragmentation or apoptosis, whereas taxol had no direct effect on these parameters. Collectively, our results strongly suggest that taxol kills

  13. Peroxisome proliferator-activated receptor-gamma-independent inhibition of macrophage activation by the non-thiazolidinedione agonist L-796,449. Comparison with the effects of 15-deoxy-delta(12,14)-prostaglandin J(2).

    Science.gov (United States)

    Castrillo, A; Mojena, M; Hortelano, S; Boscá, L

    2001-09-07

    The effects of L-796,449 (3-chloro-4-(3-(3-phenyl-7-propylbenzofuran-6-yloxy)propylthio)phenylacetic acid; referred to henceforth as compound G), a thiazolidinedione-unrelated peroxisome proliferator activated-receptor-gamma (PPAR-gamma) agonist, on early signaling in lipopolysaccharide-activated RAW 264.7 macrophages were analyzed and compared with those elicited by 15-deoxy-Delta(12,14)-prostaglandin J(2) and the thiazolidinedione rosiglitazone. Compound G inhibited the activation of nuclear factor kappa B through the impairment of the targeting and degradation of I kappa B proteins and promoted a redistribution of I kappa B alpha and I kappa B beta in the nucleus of activated cells. Compound G inhibited I kappa B kinase (IKK) activity both in vivo and in vitro, suggesting a direct mechanism of interaction between this molecule and the IKK complex. The effect of compound G on IKK activity was independent of PPAR-gamma engagement because RAW 264.7 cells expressed negligible levels of this nuclear receptor, and rosiglitazone failed to mimic these actions. Moreover, treatment of activated macrophages with compound G enhanced the synthesis of superoxide anion, which, in combination with the NO produced under activation conditions, triggered apoptosis through the intracellular synthesis of peroxynitrite. These results suggest that compound G might contribute to the resolution of inflammation by favoring the induction of apoptosis through mechanisms independent of PPAR-gamma engagement.

  14. The Ca2+ Antagonizing Effect of Chinese Cobra Venom Factor on Formation of Macrophage-derived Foam Cells

    Institute of Scientific and Technical Information of China (English)

    谭健苗; 杨向东; 姜志胜; 李亮

    2007-01-01

    Purpose CCVF was isolated from Chinese cobra (Naja naja) venom, its Ca2+ antagonizing effect on formation of macrophage-derived foam cells was explored in these studies. Methods Foam cell models were induced with C57BL/6J mouse peritoneal macrophages incubated in 10mg/L oxidized low density lipoprotein (OLDL), and their intracellular Ca2+ levels influenced both slowly and transiently by CCVF were determined with the technique of Ca2+ fluorescent indicator. Results The intracellular Ca2+ level with the macrophages incubated in 10mg/L OLDL and 10mg/L CCVF was 40.2% of the macrophages incubated in 10mg/L OLDL (P<0.05); While the transient influence of CCVF on the intracellular Ca2+ levels were not significant. Conclusion CCVF exerted a long-lasting antagonizing role on the enhancement of intracellular Ca2+ levels, thus inhibited the formation of macrophage-derived foam cell.

  15. 9-cis β-Carotene Increased Cholesterol Efflux to HDL in Macrophages

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    Sapir Bechor

    2016-07-01

    Full Text Available Cholesterol efflux from macrophages is a key process in reverse cholesterol transport and, therefore, might inhibit atherogenesis. 9-cis-β-carotene (9-cis-βc is a precursor for 9-cis-retinoic-acid (9-cis-RA, which regulates macrophage cholesterol efflux. Our objective was to assess whether 9-cis-βc increases macrophage cholesterol efflux and induces the expression of cholesterol transporters. Enrichment of a mouse diet with βc from the alga Dunaliella led to βc accumulation in peritoneal macrophages. 9-cis-βc increased the mRNA levels of CYP26B1, an enzyme that regulates RA cellular levels, indicating the formation of RA from βc in RAW264.7 macrophages. Furthermore, 9-cis-βc, as well as all-trans-βc, significantly increased cholesterol efflux to high-density lipoprotein (HDL by 50% in RAW264.7 macrophages. Likewise, food fortification with 9-cis-βc augmented cholesterol efflux from macrophages ex vivo. 9-cis-βc increased both the mRNA and protein levels of ABCA1 and apolipoprotein E (APOE and the mRNA level of ABCG1. Our study shows, for the first time, that 9-cis-βc from the diet accumulates in peritoneal macrophages and increases cholesterol efflux to HDL. These effects might be ascribed to transcriptional induction of ABCA1, ABCG1, and APOE. These results highlight the beneficial effect of βc in inhibition of atherosclerosis by improving cholesterol efflux from macrophages.

  16. Sida rhomboidea.Roxb aqueous extract down-regulates in vivo expression of vascular cell adhesion molecules in atherogenic rats and inhibits in vitro macrophage differentiation and foam cell formation.

    Science.gov (United States)

    Thounaojam, Menaka C; Jadeja, Ravirajsinh N; Salunke, Sunita P; Devkar, Ranjitsinh V; Ramachandran, A V

    2012-10-01

    The present study evaluates efficacy of Sida rhomboidea.Roxb (SR) leaves extract in ameliorating experimental atherosclerosis using in vitro and in vivo experimental models. Atherogenic (ATH) diet fed rats recorded significant increment in the serum total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), very LDL (VLDL), autoantibody against oxidized LDL (Ox-LDL), markers of LDL oxidation and decrement in high-density lipoprotein (HDL) along with increment in aortic TC and TG. The ex vivo LDL oxidation assay revealed an increased susceptibility of LDL isolated from ATH rats to undergo copper mediated oxidation. These set of changes were minimized by simultaneous co-supplementation of SR extract to ATH diet fed rats. Histopathology of aorta and immunolocalization studies recorded pronounced atheromatous plaque formation, vascular calcification, significant elastin derangements and higher expression of macrophage surface marker (F4/80), vascular cell adhesion molecule-1 (VCAM-1) and p-selectin in ATH rats. Whereas, ATH+SR rats depicted minimal evidence of atheromatous plaque formation, calcium deposition, distortion/defragmentation of elastin and accumulation of macrophages along with lowered expression of VCAM-1 and P-selectin compared to ATH rats. Further, monocyte to macrophage differentiation and in vitro foam cell formation were significantly attenuated in presence of SR extract. In conclusion, SR extract has the potency of controlling experimental atherosclerosis and can be used as promising herbal supplement in combating atherosclerosis.

  17. Cellular targets of the myeloperoxidase-derived oxidant hypothiocyanous acid (HOSCN) and its role in the inhibition of glycolysis in macrophages

    DEFF Research Database (Denmark)

    Love, D; Barrett, T.J.; White, M.Y.

    2016-01-01

    , antioxidant and structural proteins, were modified in a reversible manner in macrophages treated with HOSCN. The modification of the metabolic enzymes was associated with a decrease in basal glycolysis, glycolytic reserve, glycolytic capacity and lactate release, which was only partly reversible on further...... after the initial treatment period, which may be relevant for the propagation of inflammatory disease in smokers, who have elevated plasma levels of the HOSCN precursor, thiocyanate....

  18. Transmissible endoplasmic reticulum stress from myocardiocytes to macrophages is pivotal for the pathogenesis of CVB3-induced viral myocarditis

    Science.gov (United States)

    Zhang, Hui; Yue, Yan; Sun, Tianle; Wu, Xuejie; Xiong, Sidong

    2017-01-01

    Infiltrating macrophages have been proven as a pivotal pathological inflammatory cell subset in coxsackievirus B3 (CVB3) induced viral myocarditis. However, the mechanisms underlying the initiation and promotion of macrophage pro-inflammatory responses are still blur. We previously reported that cardiac ER stress contributed to CVB3-induced myocarditis by augmenting inflammation. In this study, we focused on the influence of ER stress on the macrophage inflammatory responses in the viral myocarditis. We found that ER stress was robustly induced in the cardiac infiltrating macrophages from CVB3-infected mice, and robustly facilitated the production of pro-inflammatory cytokines (IL-6, IL-12, MCP-1 and IP-10). Consistently, adoptive transfer of ER stressed macrophages significantly worsened the viral myocarditis; while transfer of ER stress-inhibited macrophages obviously alleviated the myocarditis. To our surprise, this significantly activated ER stress was not directly caused by the virus stimulation, but was transferred from the CVB3-infected, ER stressed myocardiocytes via soluble molecules in a TLR2, 4-independent way. In the present study, we reported that the transmissible ER stress from the infected myocardiocytes to macrophages could augment the pro-inflammatory responses and promoted the pathogenesis of viral myocarditis. Blocking ER stress transmission, instead of inhibiting its initiation, may represent novel therapeutic strategies against viral myocarditis. PMID:28176833

  19. Protein disulfide isomerase (PDI) associates with NADPH oxidase and is required for phagocytosis of Leishmania chagasi promastigotes by macrophages.

    Science.gov (United States)

    Santos, Célio X C; Stolf, Beatriz S; Takemoto, Paulo V A; Amanso, Angélica M; Lopes, Lucia R; Souza, Edna B; Goto, Hiro; Laurindo, Francisco R M

    2009-10-01

    PDI, a redox chaperone, is involved in host cell uptake of bacteria/viruses, phagosome formation, and vascular NADPH oxidase regulation. PDI involvement in phagocyte infection by parasites has been poorly explored. Here, we investigated the role of PDI in in vitro infection of J774 macrophages by amastigote and promastigote forms of the protozoan Leishmania chagasi and assessed whether PDI associates with the macrophage NADPH oxidase complex. Promastigote but not amastigote phagocytosis was inhibited significantly by macrophage incubation with thiol/PDI inhibitors DTNB, bacitracin, phenylarsine oxide, and neutralizing PDI antibody in a parasite redox-dependent way. Binding assays indicate that PDI preferentially mediates parasite internalization. Bref-A, an ER-Golgi-disrupting agent, prevented PDI concentration in an enriched macrophage membrane fraction and promoted a significant decrease in infection. Promastigote phagocytosis was increased further by macrophage overexpression of wild-type PDI and decreased upon transfection with an antisense PDI plasmid or PDI siRNA. At later stages of infection, PDI physically interacted with L. chagasi, as revealed by immunoprecipitation data. Promastigote uptake was inhibited consistently by macrophage preincubation with catalase. Additionally, loss- or gain-of-function experiments indicated that PMA-driven NADPH oxidase activation correlated directly with PDI expression levels. Close association between PDI and the p22phox NADPH oxidase subunit was shown by confocal colocalization and coimmunoprecipitation. These results provide evidence that PDI not only associates with phagocyte NADPH oxidase but also that PDI is crucial for efficient macrophage infection by L. chagasi.

  20. Compounds from Terminalia mantaly L. (Combretaceae Stem Bark Exhibit Potent Inhibition against Some Pathogenic Yeasts and Enzymes of Metabolic Significance

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    Marthe Aimée Tchuente Tchuenmogne

    2017-01-01

    Full Text Available Background: Pathogenic yeasts resistance to current drugs emphasizes the need for new, safe, and cost-effective drugs. Also, new inhibitors are needed to control the effects of enzymes that are implicated in metabolic dysfunctions such as cancer, obesity, and epilepsy. Methods: The anti-yeast extract from Terminalia mantaly (Combretaceae was fractionated and the structures of the isolated compounds established by means of spectroscopic analysis and comparison with literature data. Activity was assessed against Candida albicans, C. parapsilosis and C. krusei using the microdilution method, and against four enzymes of metabolic significance: glucose-6-phosphate dehydrogenase, human erythrocyte carbonic anhydrase I and II, and glutathione S-transferase. Results: Seven compounds, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside; 3-O-methylellagic acid; arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid; arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid glucopyranoside; 2α,3α,24-trihydroxyolean-11,13(18-dien-28-oïc acid; stigmasterol; and stigmasterol 3-O-β-d-glucopyranoside were isolated from the extract. Among those, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside, 3-O-methylellagic acid, and arjunglucoside showed anti-yeast activity comparable to that of reference fluconazole with minimal inhibitory concentrations (MIC below 32 µg/mL. Besides, Arjunglucoside potently inhibited the tested enzymes with 50% inhibitory concentrations (IC50 below 4 µM and inhibitory constant (Ki <3 µM. Conclusions: The results achieved indicate that further SAR studies will likely identify potent hit derivatives that should subsequently enter the drug development pipeline.

  1. Involvement of endoplasmic reticulum stress in the necroptosis of microglia/macrophages after spinal cord injury.

    Science.gov (United States)

    Fan, H; Tang, H-B; Kang, J; Shan, L; Song, H; Zhu, K; Wang, J; Ju, G; Wang, Y-Z

    2015-12-17

    Microglia/macrophages play a crucial role in inflammation after spinal cord injury (SCI). Although extensive studies have been performed on the mechanisms of microglia/macrophage activation and recruitment, how microglia/macrophages are eliminated remains unclear. In the present study, we observed a high-level expression of mixed lineage kinase domain-like protein (MLKL), a key molecule in the execution of necroptosis, in microglia/macrophages after SCI in mice. In vivo PI-labeling and Necrostatin-1 treatment confirmed the necroptosis of microglia/macrophages. Interestingly, our electronic microscopic (EM) study revealed that MLKL localized not only at the membrane but also on the endoplasmic reticulum (ER) of necroptotic microglia/macrophages. Furthermore, receptor-interacting protein 3 (RIP3), another necrosome component, was also found on the ER of necroptotic microglia/macrophages. And Glucose-regulated protein 78 (GRP78), an ER stress sensor, was up-regulated in MLKL-positive microglia/macrophages after SCI, suggesting a possible link between necroptosis and ER stress. In vitro, oxygen-glucose deprivation (OGD) stress induced ER stress and necroptosis in microglia. Inhibiting ER stress by 4-phenylbutyrate (4-PBA) significantly blocked the OGD-induced necroptosis of microglia. In the end, our data showed that, GRP78 and phosphorylated MLKL were co-expressed by the microglia/macrophages in the injured human spinal cord. Taken together, these results suggested that microglia/macrophages undergo an ER-stress involved necroptosis after SCI, implying that ER stress and necroptosis could be manipulated for modulating inflammation post-SCI.

  2. The macrophage activation marker sCD163 combined with markers of the Enhanced Liver Fibrosis (ELF) score predicts clinically significant portal hypertension in patients with cirrhosis

    DEFF Research Database (Denmark)

    Sandahl, T D; McGrail, R; Møller, Holger Jon

    2016-01-01

    BACKGROUND: Noninvasive identification of significant portal hypertension in patients with cirrhosis is needed in hepatology practice. AIM: To investigate whether the combination of sCD163 as a hepatic inflammation marker and the fibrosis markers of the Enhanced Liver Fibrosis score (ELF) can...... predict portal hypertension in patients with cirrhosis. METHODS: We measured sCD163 and the ELF components (hyaluronic acid, tissue inhibitor of metalloproteinase-1 and procollagen-III aminopeptide) in two separate cohorts of cirrhosis patients that underwent hepatic vein catheterisation. To test...... the predictive accuracy we developed a CD163-fibrosis portal hypertension score in an estimation cohort (n = 80) and validated the score in an independent cohort (n = 80). A HVPG ≥10 mmHg was considered clinically significant. RESULTS: Both sCD163 and the ELF components increased in a stepwise manner...

  3. Glucagon-like peptide-1 (GLP-1) induces M2 polarization of human macrophages via STAT3 activation.

    Science.gov (United States)

    Shiraishi, Daisuke; Fujiwara, Yukio; Komohara, Yoshihiro; Mizuta, Hiroshi; Takeya, Motohiro

    2012-08-24

    It is known that glucagon-like peptide-1 (GLP-1) is a hormone secreted postprandially from the L-cells of the small intestine and regulates glucose homeostasis. GLP-1 is now used for the treatment of diabetes because of its beneficial role against insulin resistance. The GLP-1 receptor (GLP-1R) is expressed on many cell types, including macrophages, and GLP-1 suppresses the development of atherosclerosis by inhibiting macrophage function. However, there have so far been few studies that have investigated the significance of GLP-1/GLP-1R signaling in macrophage activation. In the present study, we examined the effect of GLP-1 and exenatide, a GLP-1R agonist, on human monocyte-derived macrophage (HMDM) activation. We found that GLP-1 induced signal transducer and activator of transcription 3 (STAT3) activation. Silencing of GLP-1R suppressed the GLP-1-induced STAT3 activation. In addition, alternatively activated (M2) macrophage-related molecules, such as IL-10, CD163, and CD204 in HMDM, were significantly upregulated by GLP-1. Furthermore, the co-culture of 3T3-L1 adipocytes with GLP-1-treated RAW 264.7 macrophages increased the secretion of adiponectin compared to co-culture of the 3T3-L1 adipocytes with untreated RAW 264.7 macrophages. Our results demonstrate that GLP-1 induces macrophage polarization toward the M2 phenotype, which may contribute to the protective effects of GLP-1 against diabetes and cardiovascular diseases.

  4. The synthetic melanocortin (CKPV2 exerts anti-fungal and anti-inflammatory effects against Candida albicans vaginitis via inducing macrophage M2 polarization.

    Directory of Open Access Journals (Sweden)

    Hai-xia Ji

    Full Text Available In this study, we examined anti-fungal and anti-inflammatory effects of the synthetic melanocortin peptide (Ac-Cys-Lys-Pro-Val-NH22 or (CKPV2 against Candida albicans vaginitis. Our in vitro results showed that (CKPV2 dose-dependently inhibited Candida albicans colonies formation. In a rat Candida albicans vaginitis model, (CKPV2 significantly inhibited vaginal Candida albicans survival and macrophages sub-epithelial mucosa infiltration. For mechanisms study, we observed that (CKPV2 inhibited macrophages phagocytosis of Candida albicans. Meanwhile, (CKPV2 administration inhibited macrophage pro-inflammatory cytokines (TNF-α, IL-1β and IL-6 release, while increasing the arginase activity and anti-inflammatory cytokine IL-10 production, suggesting macrophages M1 to M2 polarization. Cyclic AMP (cAMP production was also induced by (CKPV2 administration in macrophages. These above effects on macrophages by (CKPV2 were almost reversed by melanocortin receptor-1(MC1R siRNA knockdown, indicating the requirement of MC1R in the process. Altogether, our results suggest that (CKPV2 exerted anti-fungal and anti-inflammatory activities against Candida albicans vaginitis probably through inducing macrophages M1 to M2 polarization and MC1R activation.

  5. The Synthetic Melanocortin (CKPV)2 Exerts Anti-Fungal and Anti-Inflammatory Effects against Candida albicans Vaginitis via Inducing Macrophage M2 Polarization

    Science.gov (United States)

    Jia, Zhi-rong; Li, Xian-jing; Wang, Zhuo; Li, Li; Li, Yong-wen; Liu, Gen-yan; Tong, Ming-Qing; Li, Xiao-yi; Zhang, Guo-hui; Dai, Xiang-rong; He, Ling; Li, Zhi-yu; Cao, Cong; Yang, Yong

    2013-01-01

    In this study, we examined anti-fungal and anti-inflammatory effects of the synthetic melanocortin peptide (Ac-Cys-Lys-Pro-Val-NH2)2 or (CKPV)2 against Candida albicans vaginitis. Our in vitro results showed that (CKPV)2 dose-dependently inhibited Candida albicans colonies formation. In a rat Candida albicans vaginitis model, (CKPV)2 significantly inhibited vaginal Candida albicans survival and macrophages sub-epithelial mucosa infiltration. For mechanisms study, we observed that (CKPV)2 inhibited macrophages phagocytosis of Candida albicans. Meanwhile, (CKPV)2 administration inhibited macrophage pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) release, while increasing the arginase activity and anti-inflammatory cytokine IL-10 production, suggesting macrophages M1 to M2 polarization. Cyclic AMP (cAMP) production was also induced by (CKPV)2 administration in macrophages. These above effects on macrophages by (CKPV)2 were almost reversed by melanocortin receptor-1(MC1R) siRNA knockdown, indicating the requirement of MC1R in the process. Altogether, our results suggest that (CKPV)2 exerted anti-fungal and anti-inflammatory activities against Candida albicans vaginitis probably through inducing macrophages M1 to M2 polarization and MC1R activation. PMID:23457491

  6. Anti-Inflammatory Cytokine Interleukin-4 Inhibits Inducible Nitric Oxide Synthase Gene Expression in the Mouse Macrophage Cell Line RAW264.7 through the Repression of Octamer-Dependent Transcription

    Directory of Open Access Journals (Sweden)

    Miki Hiroi

    2013-01-01

    Full Text Available Inducible nitric oxide synthase (iNOS is a signature molecule involved in the classical activation of M1 macrophages and is induced by the Nos2 gene upon stimulation with Th1-cell derived interferon-gamma (IFNγ and bacterial lipopolysaccharide (LPS. Although the anti-inflammatory cytokine IL-4 is known to inhibit Nos2 gene expression, the molecular mechanism involved in the negative regulation of Nos2 by IL-4 remains to be fully elucidated. In the present study, we investigated the mechanism of IL-4-mediated Nos2 transcriptional repression in the mouse macrophage-like cell line RAW264.7. Signal transducer and activator of transcription 6 (Stat6 knockdown by siRNA abolished the IL-4-mediated inhibition of Nos2 induced by IFNγ/LPS. Transient transfection of a luciferase reporter gene containing the 5′-flanking region of the Nos2 gene demonstrated that an octamer transcription factor (OCT binding site in the promoter region is required for both positive regulation by IFNγ/LPS and negative regulation by IL-4. Although IL-4 had no inhibitory effect on the DNA-binding activity of constitutively expressed Oct-1, IL-4-induced Nos2-reporter transcriptional repression was partially attenuated by overexpression of the coactivator CREB-binding protein (CBP. These results suggest that a coactivator/cofactor that functionally interacts with Oct-1 is a molecular target for the IL-4-mediated inhibition of Nos2 and that IL-4-activated Stat6 represses Oct-1-dependent transcription by competing with this coactivator/cofactor.

  7. α-Dihydroxychalcone-glycoside (α-DHC) isolated from the heartwood of Pterocarpus marsupium inhibits LPS induced MAPK activation and up regulates HO-1 expression in murine RAW 264.7 macrophage

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, Prarthana; Saraswat, Ghungroo; Kabir, Syed N., E-mail: snkabir@iicb.res.in

    2014-05-15

    Three phenolic glycosides isolated from the heartwood of Pterocarpus marsupium showed significant free radical and superoxide ion scavenging activity and antioxidant potential that were comparable to, or several folds higher than those of standard antioxidants, trolox and ascorbic acid. The effective concentrations of these compounds were far below their cytotoxic levels. Compound 3, which was characterized to be α-dihydroxychalcone-glycoside (α-DHC), was the most potent one. Subsequent studies demonstrated that α-DHC effectively reduced nitric oxide and cytokine production by the LPS stimulated RAW 264.7 mouse macrophage cell line. The compound effectively attenuated the expression of inflammation-mediating enzymes COX-2 and iNOS at the mRNA as well as protein levels in a concentration dependent manner. It prevented phosphorylation of all the three MAPKs (JNK, ERK, p38) and eventually blocked the activation of downstream elements contributing to inflammation. Phosphorylation of IκB-α and subsequent translocation of NF-κB into the nucleus were restricted, while the expression of stress responsive gene HO-1 was up-regulated. α-DHC targeted Keap-1 by modifying its cysteine thiols, dissociating it from Nrf-2 and facilitating nuclear entry of the latter; and this in turn induced HO-1 expression. Thus α-DHC exerts its anti-inflammatory activity in a dual manner: by down regulating MAPKs and restricting nuclear stabilization of NF-κB at one end, and by disrupting Nrf-2–Keap-1 complex on the other. In conclusion, the anti-inflammatory potential together with its high therapeutic index envisages α-DHC as a prospective candidate molecule for the development of therapeutic strategy against inflammatory disorders. - Highlights: • α-DHC isolated from Pterocarpus marsupium has significant antioxidant potential. • α-DHC inhibits NO, IL-6, IL-1β, TNF-α production in LPS-stimulated RAW 264.7 cells. • α-DHC down-regulates of COX-2, iNOS expression in LPS

  8. Impaired Functions of Macrophage from Cystic Fibrosis Patients: CD11b, TLR-5 Decrease and sCD14, Inflammatory Cytokines Increase

    Science.gov (United States)

    Simonin-Le Jeune, Karin; Le Jeune, André; Jouneau, Stéphane; Belleguic, Chantal; Roux, Pierre-François; Jaguin, Marie; Dimanche-Boitre, Marie-Thérèse; Lecureur, Valérie; Leclercq, Caroline; Desrues, Benoît; Brinchault, Graziella; Gangneux, Jean-Pierre; Martin-Chouly, Corinne

    2013-01-01

    Background Early in life, cystic fibrosis (CF) patients are infected with microorganisms. The role of macrophages has largely been underestimated in literature, whereas the focus being mostly on neutrophils and epithelial cells. Macrophages may however play a significant role in the initiating stages of this disease, via an inability to act as a suppressor cell. Yet macrophage dysfunction may be the first step in cascade of events leading to chronic inflammation/infection in CF. Moreover, reports have suggested that CFTR contribute to altered inflammatory response in CF by modification of normal macrophage functions. Objectives In order to highlight possible intrinsic macrophage defects due to impaired CFTR, we have studied inflammatory cytokines secretions, recognition of pathogens and phagocytosis in peripheral blood monocyte-derived macrophages from stable adult CF patients and healthy subjects (non-CF). Results In CF macrophage supernatants, concentrations of sCD14, IL-1β, IL-6, TNF-α and IL-10 were strongly raised. Furthermore expression of CD11b and TLR-5 were sorely decreased on CF macrophages. Beside, no difference was observed for mCD14, CD16, CD64, TLR-4 and TLR1/TLR-2 expressions. Moreover, a strong inhibition of phagocytosis was observed for CF macrophages. Elsewhere CFTR inhibition in non-CF macrophages also led to alterations of phagocytosis function as well as CD11b expression. Conclusions Altogether, these findings demonstrate excessive inflammation in CF macrophages, characterized by overproduction of sCD14 and inflammatory cytokines, with decreased expression of CD11b and TLR-5, and impaired phagocytosis. This leads to altered clearance of pathogens and non-resolution of infection by CF macrophages, thereby inducing an exaggerated pro-inflammatory response. PMID:24098711

  9. Omega-3 polyunsaturated fatty acids antagonize macrophage inflammation via activation of AMPK/SIRT1 pathway.

    Directory of Open Access Journals (Sweden)

    Bingzhong Xue

    Full Text Available Macrophages play a key role in obesity-induced inflammation. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA exert anti-inflammatory functions in both humans and animal models, but the exact cellular signals mediating the beneficial effects are not completely understood. We previously found that two nutrient sensors AMP-activated protein kinase (AMPK and SIRT1 interact to regulate macrophage inflammation. Here we aim to determine whether ω-3 PUFAs antagonize macrophage inflammation via activation of AMPK/SIRT1 pathway. Treatment of ω-3 PUFAs suppresses lipopolysaccharide (LPS-induced cytokine expression in macrophages. Luciferase reporter assays, electrophoretic mobility shift assays (EMSA and Chromatin immunoprecipitation (ChIP assays show that treatment of macrophages with ω-3 PUFAs significantly inhibits LPS-induced NF-κB signaling. Interestingly, DHA also increases expression, phosphorylation and activity of the major isoform α1AMPK, which further leads to SIRT1 over-expression. More importantly, DHA mimics the effect of SIRT1 on deacetylation of the NF-κB subunit p65, and the ability of DHA to deacetylate p65 and inhibit its signaling and downstream cytokine expression require SIRT1. In conclusion, ω-3 PUFAs negatively regulate macrophage inflammation by deacetylating NF-κB, which acts through activation of AMPK/SIRT1 pathway. Our study defines AMPK/SIRT1 as a novel cellular mediator for the anti-inflammatory effects of ω-3 PUFAs.

  10. EFFECT OF METHIONINE ENKEPHALIN ON MIGRATION OF MACROPHAGES FROM MICE WITH IMPAIRED LIVER

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To observe the effects of methionine enkephalin (M-Enk) on migration of macrophages from mice with impaired liver and its immunomodulatory mechanisms. Methods Liver of mice was impaired by feeding CCl4 and macrophage migration inhibitory factor (MMIF) was produced by Con A-stimulated spleen lympho- cytes. Inhibition of macrophage migration was measured in reaction system by adding M-Enk. Results Migration of macrophages in both liver-impaired and control group were suppressed by MMIF, but the suppression might be re- versed by adding 1 μmol/L M-Enk (P<0. 05). M-Enk could significantly inhibit in vitro both of the combination of MMIF with macrophages and production of MMIF from lymphocytes (P<0. 01). Macrophages from liver-imparied group showed a higher sensitivity compared to the control group (P<0. 05). Conclusion The study suggests that opi- oid peptieds play an important role in the modulation of the immune response under stress as liver impairment.

  11. Ascofuranone inhibits lipopolysaccharide-induced inflammatory response via NF-kappaB and AP-1, p-ERK, TNF-α, IL-6 and IL-1β in RAW 264.7 macrophages.

    Science.gov (United States)

    Park, Jun-Young; Chung, Tae-Wook; Jeong, Yun-Jeong; Kwak, Choong-Hwan; Ha, Sun-Hyung; Kwon, Kyung-Min; Abekura, Fukushi; Cho, Seung-Hak; Lee, Young-Choon; Ha, Ki-Tae; Magae, Junji; Chang, Young-Chae; Kim, Cheorl-Ho

    2017-01-01

    The natural fungal compound ascofuranone (5-chloro-3-[(2E,6E)-7-[(2S)-5,5-dimethyl-4-oxo-tetrahydrofuran-2-yl]-3-methyl-octa-2,6-dienyl]-2,4-dihydroxy-6-methyl-benzaldehyde, MW 420.93) (AF) isolated from Ascochyta viciae has been known to promote cell cycle arrest and inhibit invasion of tumor cells. We have previously studied a structurally similar compound ascochlorin (ASC; MW 404.93) with regard to its anti-inflammatory activity in LPS- stimulated RAW 264.7 macrophages. In order to examine the relationship between the anti-inflammatory activities and the molecular differences between AF and ASC, the activity of AF is herein studied, because ASC has a unique trimethyl oxocyclohexyl structure, while AF has a unique dimethyl-oxo-tetrahydrofuran structure. AF dose-dependently inhibited the production of NO and iNOS and the COX-2 mRNA and protein levels in RAW 264.7 cells. In addition, AF suppressed mRNA expression levels of inflammatory cytokines such as TNF-α, IL-6, and IL-1β, as assessed by RT-PCR. AF (30-50 μg/ml) treatment clearly inhibited the nuclear translocation of NF-κB, AP-1 (p-c-Jun) from the cytosolic space. Phosphorylation of IκB, which functions to maintain the activity of NF-κB, was decreased by AF treatment. Moreover, AF suppressed the binding of NF-κB (p65). Inhibition of IkBa phosphorylation and degradation inhibits nuclear translocation of p65. Immunofluorescence confocal microscopy analysis also revealed that translocation of NF-κB and AP-1 (p-c-Jun) was decreased upon AF treatment. AF specifically decreased the expression level of p-ERK, but not the expression level of p-p38 or p-JNK. Given these results, we suggest that AF suppresses the inflammatory response by targeting p-ERK. This indicates that AF is a negative regulator of LPS-stimulated nuclear translocation of NF-κB and AP-1 (p-c-Jun) in RAW 264.7 macrophages, and specifically it targets p-ERK. Therefore, AF and ASC exert their effects in different ways, most probably because

  12. Enhancement of Anti-Inflammatory Activity of Curcumin Using Phosphatidylserine-Containing Nanoparticles in Cultured Macrophages

    Directory of Open Access Journals (Sweden)

    Ji Wang

    2016-06-01

    Full Text Available Macrophages are one kind of innate immune cells, and produce a variety of inflammatory cytokines in response to various stimuli, such as oxidized low density lipoprotein found in the pathogenesis of atherosclerosis. In this study, the effect of phosphatidylserine on anti-inflammatory activity of curcumin-loaded nanostructured lipid carriers was investigated using macrophage cultures. Different amounts of phosphatidylserine were used in the preparation of curcumin nanoparticles, their physicochemical properties and biocompatibilities were then compared. Cellular uptake of the nanoparticles was investigated using a confocal laser scanning microscope and flow cytometry analysis in order to determine the optimal phosphatidylserine concentration. In vitro anti-inflammatory activities were evaluated in macrophages to test whether curcumin and phosphatidylserine have interactive effects on macrophage lipid uptake behavior and anti-inflammatory responses. Here, we showed that macrophage uptake of phosphatidylserine-containing nanostructured lipid carriers increased with increasing amount of phosphatidylserine in the range of 0%–8%, and decreased when the phosphatidylserine molar ratio reached over 12%. curcumin-loaded nanostructured lipid carriers significantly inhibited lipid accumulation and pro-inflammatory factor production in cultured macrophages, and evidently promoted release of anti-inflammatory cytokines, when compared with curcumin or phosphatidylserine alone. These results suggest that the delivery system using PS-based nanoparticles has great potential for efficient delivery of drugs such as curcumin, specifically targeting macrophages and modulation of their anti-inflammatory functions.

  13. MicroRNA-155 in exosomes secreted from helicobacter pylori infection macrophages immunomodulates inflammatory response

    Science.gov (United States)

    Wang, Jianjun; Deng, Zhiyong; Wang, Zeyou; Wu, Jianhong; Gu, Tao; Jiang, Yibiao; Li, Guangxin

    2016-01-01

    Exosomes containing microRNA-155 act as molecule carriers during immune cell-cell communication and play an important role in the inflammatory response of H. pylori infection macrophages. Previous reports have found that miR-155 was over-expressed in H. pylori infection macrophages, but the significance of which is still unknown. In this study, we analyzed the impact of miR-155 loaded in exosomes derived from macrophages to the inflammatory response of H. pylori infection macrophages and possible mechanisms. We found that miR-155 promoted the expression of inflammatory cytokines including TNF-a, IL-6, IL-23, but also increased the expression of CD40, CD63, CD81, and MCH-I. Meanwhile, inflammatory signal pathways proteins, such as MyD88, NF-κB in H. pylori infection macrophages were down-regulated due to the over-expression of miR-155. Experiments in vitro or in vivo revealed that miR-155 promoted macrophages to inhibit or kill H. pylori by regulating the inflammatory response of cells to prevent the gastritis caused by H. pylori infection. These findings contribute to the understanding of miR-155 contained in exosomes in inflammatory responses of H. pylori infection macrophages. PMID:27725852

  14. Staphylococcal superantigen-like protein 3 binds to the Toll-like receptor 2 extracellular domain and inhibits cytokine production induced by Staphylococcus aureus, cell wall component, or lipopeptides in murine macrophages.

    Science.gov (United States)

    Yokoyama, Ryosuke; Itoh, Saotomo; Kamoshida, Go; Takii, Takemasa; Fujii, Satoshi; Tsuji, Tsutomu; Onozaki, Kikuo

    2012-08-01

    Staphylococcal superantigen-like proteins (SSLs) are a family of exoproteins sharing structural similarity with superantigens, but no superantigenic activity. Corresponding host target proteins or receptors against a portion of SSLs in the family have been identified. In this study, we show that SSL3 specifically binds to Toll-like receptor 2 (TLR2) and inhibits the stimulation of macrophages by TLR2 ligands. An approximately 100-kDa protein was recovered by using recombinant His-tagged SSL3-conjugated Sepharose from the lysate of porcine spleen, and the protein was identified as porcine TLR2 by peptide mass fingerprinting analysis. The SSL3-conjugated Sepharose recovered human and mouse TLR2 but not TLR4 from human neutrophils and mouse macrophage RAW 264.7 cells, as well as a recombinant TLR2 extracellular domain chimera protein. The production levels of interleukin 12 (IL-12) from mouse macrophages treated with heat-killed Staphylococcus aureus and of tumor necrosis factor alpha (TNF-α) from RAW 264.7 cells induced by peptidoglycan or lipopeptide TLR2 ligands were strongly suppressed in the presence of SSL3. The mutation of consensus sialic acid-containing glycan-binding residues in SSL3 did not abrogate the binding ability to TLR2 or inhibitory activity on TLR2, indicating that the interaction of SSL3 with TLR2 was independent of the sialic acid-containing glycan-binding residues. These findings demonstrate that SSL3 is able to bind the extracellular domain of TLR2 and interfere with TLR2 function. The present study provides a novel mechanism of SSL3 in immune evasion of S. aureus via interfering with its recognition by innate immune cells.

  15. Urokinase plasminogen activator inhibits HIV virion release from macrophage-differentiated chronically infected cells via activation of RhoA and PKCε.

    Directory of Open Access Journals (Sweden)

    Francesca Graziano

    Full Text Available BACKGROUND: HIV replication in mononuclear phagocytes is a multi-step process regulated by viral and cellular proteins with the peculiar feature of virion budding and accumulation in intra-cytoplasmic vesicles. Interaction of urokinase-type plasminogen activator (uPA with its cell surface receptor (uPAR has been shown to favor virion accumulation in such sub-cellular compartment in primary monocyte-derived macrophages and chronically infected promonocytic U1 cells differentiated into macrophage-like cells by stimulation with phorbol myristate acetate (PMA. By adopting this latter model system, we have here investigated which intracellular signaling pathways were triggered by uPA/uPAR interaction leading the redirection of virion accumulation in intra-cytoplasmic vesicles. RESULTS: uPA induced activation of RhoA, PKCδ and PKCε in PMA-differentiated U1 cells. In the same conditions, RhoA, PKCδ and PKCε modulated uPA-induced cell adhesion and polarization, whereas only RhoA and PKCε were also responsible for the redirection of virions in intracellular vesicles. Distribution of G and F actin revealed that uPA reorganized the cytoskeleton in both adherent and polarized cells. The role of G and F actin isoforms was unveiled by the use of cytochalasin D, a cell-permeable fungal toxin that prevents F actin polymerization. Receptor-independent cytoskeleton remodeling by Cytochalasin D resulted in cell adhesion, polarization and intracellular accumulation of HIV virions similar to the effects gained with uPA. CONCLUSIONS: These findings illustrate the potential contribution of the uPA/uPAR system in the generation and/or maintenance of intra-cytoplasmic vesicles that actively accumulate virions, thus sustaining the presence of HIV reservoirs of macrophage origin. In addition, our observations also provide evidences that pathways controlling cytoskeleton remodeling and activation of PKCε bear relevance for the design of new antiviral strategies aimed

  16. DMPD: Inhibition of toll-like receptor and cytokine signaling--a unifying theme inischemic tolerance. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15545925 Inhibition of toll-like receptor and cytokine signaling--a unifying theme ...png) (.svg) (.html) (.csml) Show Inhibition of toll-like receptor and cytokine signaling--a unifying theme i...nischemic tolerance. PubmedID 15545925 Title Inhibition of toll-like receptor and... cytokine signaling--a unifying theme inischemic tolerance. Authors Kariko K, Weissman D, Welsh FA. Publicat

  17. Cholesterol efflux from THP-1 macrophages is impaired by the fatty acid component from lipoprotein hydrolysis by lipoprotein lipase.

    Science.gov (United States)

    Yang, Yanbo; Thyagarajan, Narmadaa; Coady, Breanne M; Brown, Robert J

    2014-09-05

    Lipoprotein lipase (LPL) is an extracellular lipase that primarily hydrolyzes triglycerides within circulating lipoproteins. Macrophage LPL contributes to atherogenesis, but the mechanisms behind it are poorly understood. We hypothesized that the products of lipoprotein hydrolysis generated by LPL promote atherogenesis by inhibiting the cholesterol efflux ability by macrophages. To test this hypothesis, we treated human THP-1 macrophages with total lipoproteins that were hydrolyzed by LPL and we found significantly reduced transcript levels for the cholesterol transporters ATP binding cassette transporter A1 (ABCA1), ABCG1, and scavenger receptor BI. These decreases were likely due to significant reductions for the nuclear receptors liver-X-receptor-α, peroxisome proliferator activated receptor (PPAR)-α, and PPAR-γ. We prepared a mixture of free fatty acids (FFA) that represented the ratios of FFA species within lipoprotein hydrolysis products, and we found that the FFA mixture also significantly reduced cholesterol transporters and nuclear receptors. Finally, we tested the efflux of cholesterol from THP-1 macrophages to apolipoprotein A-I, and we found that the treatment of THP-1 macrophages with the FFA mixture significantly attenuated cholesterol efflux. Overall, these data show that the FFA component of lipoprotein hydrolysis products generated by LPL may promote atherogenesis by inhibiting cholesterol efflux, which partially explains the pro-atherogenic role of macrophage LPL.

  18. Silencing CCR2 in Macrophages Alleviates Adipose Tissue Inflammation and the Associated Metabolic Syndrome in Dietary Obese Mice

    Directory of Open Access Journals (Sweden)

    Jongkil Kim

    2016-01-01

    Full Text Available Adipose tissue macrophage (ATM-mediated inflammation is a key feature contributing to the adverse metabolic outcomes of dietary obesity. Recruitment of macrophages to obese adipose tissues (AT can occur through the engagement of CCR2, the receptor for MCP-1 (monocyte chemoattractant protein-1, which is expressed on peripheral monocytes/macrophages. Here, we show that i.p. administration of a rabies virus glycoprotein-derived acetylcholine receptor-binding peptide effectively delivers complexed siRNA into peritoneal macrophages and ATMs in a mouse model of high-fat diet-induced obesity. Treatment with siRNA against CCR2 inhibited macrophage infiltration and accumulation in AT and, therefore, proinflammatory cytokines produced by macrophages. Consequently, the treatment significantly improved glucose tolerance and insulin sensitivity profiles, and also alleviated the associated symptoms of hepatic steatosis and reduced hepatic triglyceride production. These results demonstrate that disruption of macrophage chemotaxis to the AT through cell-targeted gene knockdown strategies can provide a therapeutic intervention for obesity-related metabolic diseases. The study also highlights a siRNA delivery approach for targeting specific monocyte subsets that contribute to obesity-associated inflammation without affecting the function of other tissue-resident macrophages that are essential for host homeostasis and survival.

  19. Hydrogen Sulfide Recruits Macrophage Migration by Integrin β1-Src-FAK/Pyk2-Rac Pathway in Myocardial Infarction

    Science.gov (United States)

    Miao, Lei; Xin, Xiaoming; Xin, Hong; Shen, Xiaoyan; Zhu, Yi-Zhun

    2016-03-01

    Myocardial infarction (MI) triggers an inflammatory reaction, in which macrophages are of key importance for tissue repairing. Infiltration and/or migration of macrophages into the infarct area early after MI is critical for infarct healing, vascularization, and cardiac function. Hydrogen sulfide (H2S) has been demonstrated to possess cardioprotective effects post MI and during the progress of cardiac remodeling. However, the specific molecular and cellular mechanisms involved in macrophage recruitment by H2S remain to be identified. In this study, the NaHS (exogenous sources of H2S) treatment exerted an increased infiltration of macrophages into the infarcted myocardium at early stage of MI cardiac tissues in both wild type (WT) and cystathionine-γ-lyase-knockout (CSE-KO) mice. And NaHS accelerated the migration of macrophage cells in vitro. While, the inhibitors not only significantly diminished the migratory ability in response to NaHS, but also blocked the activation of phospho-Src, -Pyk2, -FAK397, and -FAK925. Furthermore, NaHS induced the internalization of integrin β1 on macrophage surface, but, integrin β1 silencing inhibited macrophage migration and Src signaling activation. These results indicate that H2S may have the potential as an anti-infarct of MI by governing macrophage migration, which was achieved by accelerating internalization of integrin β1 and activating downstream Src-FAK/Pyk2-Rac pathway.

  20. Phenolic-extract from argan oil (Argania spinosa L.) inhibits human low-density lipoprotein (LDL) oxidation and enhances cholesterol efflux from human THP-1 macrophages.

    Science.gov (United States)

    Berrougui, Hicham; Cloutier, Martin; Isabelle, Maxim; Khalil, Abdelouahed

    2006-02-01

    Argan oil is rich in unsaturated fatty acids, tocopherol and phenolic compounds. These protective molecules make further study of its cardiovascular diseases (CVDs) action interesting. Furthermore, no previous study has explored the antioxidant activity of argan oil in comparison with olive oil. The present study was conducted to evaluate the beneficial properties of Virgin argan oil phenolic extracts (VAO-PE) towards CVD by: (A) protecting human (low-density lipoprotein, LDL) against lipid peroxidation and (B) promoting high-density lipoprotein (HDL)-mediated cholesterol efflux. Human LDLs were oxidized by incubation with CuSO(4) in the presence of different concentrations of VAO-PE (0-320mug/ml). LDL lipid peroxidation was evaluated by conjugated diene and MDA formation as well as Vitamin E disappearance. Incubation of LDL with VAO-PE significantly prolonged the lag-phase and lowered the progression rate of lipid peroxidation (Pargan oil provides a source of dietary phenolic antioxidants, which prevent cardiovascular diseases by inhibiting LDL-oxidation and enhancing reverse cholesterol transport. These properties increase the anti-atherogenic potential of HDL.

  1. Brazilian Red Propolis Attenuates Inflammatory Signaling Cascade in LPS-Activated Macrophages

    Science.gov (United States)

    Bueno-Silva, Bruno; Kawamoto, Dione; Ando-Suguimoto, Ellen S.; Alencar, Severino M.; Rosalen, Pedro L.; Mayer, Marcia P. A.

    2015-01-01

    Although previous studies suggested an anti-inflammatory property of Brazilian red propolis (BRP), the mechanisms involved in the anti-inflammatory effects of BRP and its activity on macrophages were still not elucidated. This study aimed to evaluate whether BRP attenuates the inflammatory effect of LPS on macrophages and to investigate its underlying mechanisms. BRP was added to RAW 264.7 murine macrophages after activation with LPS. NO production, cell viability, cytokines profile were evaluated. Activation of inflammatory signaling pathways and macrophage polarization were determined by RT-qPCR and Western blot. BRP at 50 μg/ml inhibited NO production by 78% without affecting cell viability. Cd80 and Cd86 were upregulated whereas mrc1 was down regulated by BRP indicating macrophage polarization at M1. BRP attenuated the production of pro-inflammatory mediators IL-12, GM-CSF, IFN-Ɣ, IL-1β in cell supernatants although levels of TNF- α and IL-6 were slightly increased after BRP treatment. Levels of IL-4, IL-10 and TGF-β were also reduced by BRP. BRP significantly reduced the up-regulation promoted by LPS of transcription of genes in inflammatory signaling (Pdk1, Pak1, Nfkb1, Mtcp1, Gsk3b, Fos and Elk1) and of Il1β and Il1f9 (fold-change rate > 5), which were further confirmed by the inhibition of NF-κB and MAPK signaling pathways. Furthermore, the upstream adaptor MyD88 adaptor-like (Mal), also known as TIRAP, involved in TLR2 and TLR4 signaling, was down- regulated in BRP treated LPS-activated macrophages. Given that BRP inhibited multiple signaling pathways in macrophages involved in the inflammatory process activated by LPS, our data indicated that BRP is a noteworthy food-source for the discovery of new bioactive compounds and a potential candidate to attenuate exhacerbated inflammatory diseases. PMID:26660901

  2. Brazilian Red Propolis Attenuates Inflammatory Signaling Cascade in LPS-Activated Macrophages.

    Directory of Open Access Journals (Sweden)

    Bruno Bueno-Silva

    Full Text Available Although previous studies suggested an anti-inflammatory property of Brazilian red propolis (BRP, the mechanisms involved in the anti-inflammatory effects of BRP and its activity on macrophages were still not elucidated. This study aimed to evaluate whether BRP attenuates the inflammatory effect of LPS on macrophages and to investigate its underlying mechanisms. BRP was added to RAW 264.7 murine macrophages after activation with LPS. NO production, cell viability, cytokines profile were evaluated. Activation of inflammatory signaling pathways and macrophage polarization were determined by RT-qPCR and Western blot. BRP at 50 μg/ml inhibited NO production by 78% without affecting cell viability. Cd80 and Cd86 were upregulated whereas mrc1 was down regulated by BRP indicating macrophage polarization at M1. BRP attenuated the production of pro-inflammatory mediators IL-12, GM-CSF, IFN-Ɣ, IL-1β in cell supernatants although levels of TNF- α and IL-6 were slightly increased after BRP treatment. Levels of IL-4, IL-10 and TGF-β were also reduced by BRP. BRP significantly reduced the up-regulation promoted by LPS of transcription of genes in inflammatory signaling (Pdk1, Pak1, Nfkb1, Mtcp1, Gsk3b, Fos and Elk1 and of Il1β and Il1f9 (fold-change rate > 5, which were further confirmed by the inhibition of NF-κB and MAPK signaling pathways. Furthermore, the upstream adaptor MyD88 adaptor-like (Mal, also known as TIRAP, involved in TLR2 and TLR4 signaling, was down- regulated in BRP treated LPS-activated macrophages. Given that BRP inhibited multiple signaling pathways in macrophages involved in the inflammatory process activated by LPS, our data indicated that BRP is a noteworthy food-source for the discovery of new bioactive compounds and a potential candidate to attenuate exhacerbated inflammatory diseases.

  3. Brazilian Red Propolis Attenuates Inflammatory Signaling Cascade in LPS-Activated Macrophages.

    Science.gov (United States)

    Bueno-Silva, Bruno; Kawamoto, Dione; Ando-Suguimoto, Ellen S; Alencar, Severino M; Rosalen, Pedro L; Mayer, Marcia P A

    2015-01-01

    Although previous studies suggested an anti-inflammatory property of Brazilian red propolis (BRP), the mechanisms involved in the anti-inflammatory effects of BRP and its activity on macrophages were still not elucidated. This study aimed to evaluate whether BRP attenuates the inflammatory effect of LPS on macrophages and to investigate its underlying mechanisms. BRP was added to RAW 264.7 murine macrophages after activation with LPS. NO production, cell viability, cytokines profile were evaluated. Activation of inflammatory signaling pathways and macrophage polarization were determined by RT-qPCR and Western blot. BRP at 50 μg/ml inhibited NO production by 78% without affecting cell viability. Cd80 and Cd86 were upregulated whereas mrc1 was down regulated by BRP indicating macrophage polarization at M1. BRP attenuated the production of pro-inflammatory mediators IL-12, GM-CSF, IFN-Ɣ, IL-1β in cell supernatants although levels of TNF- α and IL-6 were slightly increased after BRP treatment. Levels of IL-4, IL-10 and TGF-β were also reduced by BRP. BRP significantly reduced the up-regulation promoted by LPS of transcription of genes in inflammatory signaling (Pdk1, Pak1, Nfkb1, Mtcp1, Gsk3b, Fos and Elk1) and of Il1β and Il1f9 (fold-change rate > 5), which were further confirmed by the inhibition of NF-κB and MAPK signaling pathways. Furthermore, the upstream adaptor MyD88 adaptor-like (Mal), also known as TIRAP, involved in TLR2 and TLR4 signaling, was down- regulated in BRP treated LPS-activated macrophages. Given that BRP inhibited multiple signaling pathways in macrophages involved in the inflammatory process activated by LPS, our data indicated that BRP is a noteworthy food-source for the discovery of new bioactive compounds and a potential candidate to attenuate exhacerbated inflammatory diseases.

  4. Isoliquiritigenin, a flavonoid from licorice, blocks M2 macrophage polarization in colitis-associated tumorigenesis through downregulating PGE{sub 2} and IL-6

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Haixia [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Zhang, Xinhua [Department of Liver, Biliary And Pancreatic Tumors, Hubei Cancer Hospital, Wuhan 430079 (China); Chen, Xuewei; Li, Ying; Ke, Zunqiong [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Tang, Tian [Department of Oncology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Chai, Hongyan [Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan 430071 (China); Guo, Austin M. [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China); Department of Pharmacology, New York Medical College, Valhalla, NY 10595 (United States); Chen, Honglei, E-mail: hl-chen@whu.edu.cn [Department of Pathology and Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Yang, Jing, E-mail: yangjingliu2013@163.com [Department of Pharmacology, School of Medicine, Wuhan University, Wuhan 430071 (China)

    2014-09-15

    M2 macrophage polarization is implicated in colorectal cancer development. Isoliquiritigenin (ISL), a flavonoid from licorice, has been reported to prevent azoxymethane (AOM) induced colon carcinogenesis in animal models. Here, in a mouse model of colitis-associated tumorigenesis induced by AOM/dextran sodium sulfate (DSS), we investigated the chemopreventive effects of ISL and its mechanisms of action. Mice were treated with AOM/DSS and randomized to receive either vehicle or ISL (3, 15 and 75 mg/kg). Tumor load, histology, immunohistochemistry, and gene and protein expressions were determined. Intragastric administration of ISL for 12 weeks significantly decreased colon cancer incidence, multiplicity and tumor size by 60%, 55.4% and 42.6%, respectively. Moreover, ISL inhibited M2 macrophage polarization. Such changes were accompanied by downregulation of PGE{sub 2} and IL-6 signaling. Importantly, depletion of macrophages by clodronate (Clod) or zoledronic acid (ZA) reversed the effects of ISL. In parallel, in vitro studies also demonstrated that ISL limited the M2 polarization of RAW264.7 cells and mouse peritoneal macrophages with concomitant inactivation of PGE{sub 2}/PPARδ and IL-6/STAT3 signaling. Conversely, exogenous addition of PGE{sub 2} or IL-6, or overexpression of constitutively active STAT3 reversed ISL-mediated inhibition of M2 macrophage polarization. In summary, dietary flavonoid ISL effectively inhibits colitis-associated tumorigenesis through hampering M2 macrophage polarization mediated by the interplay between PGE{sub 2} and IL-6. Thus, inhibition of M2 macrophage polarization is likely to represent a promising strategy for chemoprevention of colorectal cancer. - Highlights: • Isoliquiritigenin (ISL) prevents colitis-associated tumorigenesis. • ISL inhibits M2 macrophage polarization in vivo and in vitro. • ISL inhibits PGE{sub 2} and IL-6 signaling in colitis-associated tumorigenesis. • ISL may be an attractive candidate agent for

  5. Ethanolic extract of Passiflora edulis Sims leaves inhibits protein glycation and restores the oxidative burst in diabetic rat macrophages after Candida albicans exposure

    Directory of Open Access Journals (Sweden)

    Carolina Fernandes Ribas Martins

    2015-12-01

    Full Text Available abstract This study was conducted to evaluate the effects of the ethanolic extract of Passiflora edulis leaves on blood glucose, protein glycation, NADPH oxidase activity and macrophage phagocytic capacity after Candida albicans exposure in diabetic rats. The Passiflora edulis Sims leaves were dried to 40°C, powdered, extracted by maceration in 70% ethanol, evaporated under reduced pressure and lyophilised. The biochemical tests performed were total phenolic content (TP as determined by the Folin-Ciocalteu assay, trapping potential DPPH assay and total iron-reducing potential. Diabetes was induced by alloxan injection. Protein glycation was determined by AGE and fructosamine serum concentrations. Extract-treated diabetic animals demonstrated lower fructosamine concentrations compared with the diabetic group. Our results suggest that ethanolic Passiflora edulis Sims leaf extraction may have beneficial effects on diabetes and may improve glycaemic control in diabetic rats.

  6. Pomegranate juice polyphenols induce a phenotypic switch in macrophage polarization favoring a M2 anti-inflammatory state.

    Science.gov (United States)

    Aharoni, Saar; Lati, Yoni; Aviram, Michael; Fuhrman, Bianca

    2015-01-01

    It was documented that pomegranate has anti-inflammatory effects. In this study, we investigated a direct effect of pomegranate juice (PJ) and its polyphenols on macrophage inflammatory phenotype. In vitro, PJ and its major polyphenols dose-dependently attenuated macrophage response to M1 proinflammatory activation in J774.A1 macrophage-like cell line. This was evidenced by a significant decrease in TNFα and IL-6 secretion in response to stimulation by IFNγ and Lipopolysaccharide. In addition, PJ and punicalagin dose-dependently promoted the macrophages toward a M2 anti-inflammatory phenotype, as determined by a significant increase in the spontaneous secretion of IL-10. In mice, supplementation with dietary PJ substantially inhibited the M2 to M1 macrophage phenotypic shift associated with age, toward a favorable anti-inflammatory M2 phenotype. This effect was also reflected in the mice atherosclerotic plaques, as evaluated by the distinct expression of arginase isoforms. PJ consumption inhibited the increment of arginase II (Arg II, M1) mRNA expression during aging, and maintained the levels of Arg I (M2) expression similar to those in young mice aorta. This study demonstrates, for the first time, that pomegranate polyphenols directly suppress macrophage inflammatory responses and promote M1 to M2 switch in macrophage phenotype. Furthermore, this study indicates that PJ consumption may inhibit the progressive proinflammatory state in the aorta along atherosclerosis development with aging, due to a switch in macrophage phenotype from proinflammatory M1 to anti-inflammatory M2.

  7. Transmembrane TNF-α Reverse Signaling Inhibits Lipopolysaccharide-Induced Proinflammatory Cytokine Formation in Macrophages by Inducing TGF-β: Therapeutic Implications.

    Science.gov (United States)

    Pallai, Anna; Kiss, Beáta; Vereb, György; Armaka, Marietta; Kollias, George; Szekanecz, Zoltán; Szondy, Zsuzsa

    2016-02-01

    TNF-α, a potent proinflammatory cytokine, is generated in a precursor form called transmembrane (m)TNF-α that is expressed as a type II polypeptide on the surface of certain cells. mTNF-α was shown to act both as a ligand by binding to TNF-α receptors, as well as a receptor that transmits outside-to-inside (reverse) signals back into the mTNF-α-bearing cells. In this study, we show that nonactivated macrophages express basal levels of mTNF-α and respond to anti-TNF-α Abs by triggering the MAPK kinase 4 signaling pathway. The pathway induces TGF-β. Based on inhibitory experiments, the production of TGF-β1 is regulated via Jun kinases, whereas that of other TGF-βs is regulated via p38 MAPKs. Exposure to LPS further induced the expression of mTNF-α, and triggering of mTNF-α strongly suppressed the LPS-induced proinflammatory response. Neutralizing TGF-β by Abs prevented the mTNF-α-mediated suppression of LPS-induced proinflammatory cytokine formation, indicating that the immune-suppressive effect of mTNF-α is mediated via TGF-β. Although apoptotic cells are also known to suppress LPS-induced proinflammatory cytokine formation in macrophages by upregulating TGF-β, we show that they do not use the mTNF-α signaling pathway. Because TGF-β possesses a wide range of immune-suppressive effects, our data indicate that upregulation of TGF-β synthesis by those TNF-α-targeting molecules, which are able to trigger mTNF-α, might contribute to their therapeutic effect in the treatment of certain inflammatory diseases such as Crohn's disease, Wegener's granulomatosis, or sarcoidosis. Additionally, none of the TNF-α-targeting molecules is expected to interfere with the immune-silencing effects of apoptotic cells.

  8. IL-1α and IL-1β-producing macrophages populate lung tumor lesions in mice.

    Science.gov (United States)

    Terlizzi, Michela; Colarusso, Chiara; Popolo, Ada; Pinto, Aldo; Sorrentino, Rosalinda

    2016-09-06

    Macrophages highly populate tumour microenvironment and are referred to as tumor-associated macrophages (TAMs). The inflammasome is a multiprotein complex responsible of IL-1 like cytokines release, which biology has been widely studied by using bone-marrow-derived macrophages to mimic a physiological and/or host defense condition. To understand the role of this complex in lung tumor-associated macrophages (TAMs), we isolated and cultured broncho-alveolar lavage (BAL)-derived cells of lung tumor-bearing mice. The stimulation of lung TAMs with LPS+ATP increased the release of IL-1β. The inhibition of NLRP3 by means of glybenclamide significantly reduced IL-1β release. Similarly, C3H-derived, caspase-1 ko and caspase-11 ko TAMs released significantly reduced levels of IL-1β. Moreover, the stimulation of lung TAMs with the sole LPS induced a significant release of IL-1α, which was significantly reduced after caspase-1 pharmacological inhibition, and in TAMs genetically lacking caspase-1 and caspase-11. The inhibition of calpain I/II by means of MDL28170 did not alter IL-1α release after LPS treatment of lung TAMs. To note, the inoculation of LPS-treated bone marrow-derived macrophages into carcinogen-exposed mice increased lung tumor formation. In contrast, the depletion of TAMs by means of clodronate liposomes reduced lung tumorigenesis, associated to lower in vivo release of IL-1α and IL-1β.In conclusion, our data imply lung tumor lesions are populated by macrophages which pro-tumor activity is regulated by the activation of the NLRP3 inflammasome that leads to the release of IL-1α and IL-1β in a caspase-11/caspase-1-dependent manner.

  9. Macrophage responsiveness to light therapy

    Energy Technology Data Exchange (ETDEWEB)

    Young, S.; Bolton, P.; Dyson, M.; Harvey, W.; Diamantopoulos, C. (United Medical School, London (England))

    1989-01-01

    Macrophages are a source of many important mediators of wound repair. It was the purpose of this study to see if light could stimulate the release of these mediators. In this study an established macrophage-like cell line (U-937) was used. The cells were exposed in culture to the following wavelengths of light: 660 nm, 820 nm, 870 nm, and 880 nm. The 820-nm source was coherent and polarised, and the others were non-coherent. Twelve hours after exposure the macrophage supernatant was removed and placed on 3T3 fibroblast cultures. Fibroblast proliferation was assessed over a 5-day period. The results showed that 660-nm, 820-nm, and 870-nm wavelengths encouraged the macrophages to release factors that stimulated fibroblast proliferation above the control levels, whereas the 880-nm wavelength either inhibited the release of these factors or encouraged the release of some inhibitory factors of fibroblast proliferation. These results suggest that light at certain wavelengths may be a useful therapeutic agent by providing a means of either stimulating or inhibiting fibroblast proliferation where necessary. At certain wavelengths coherence is not essential.

  10. Variation in HIV-1 R5 macrophage-tropism correlates with sensitivity to reagents that block envelope: CD4 interactions but not with sensitivity to other entry inhibitors

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    Simmonds Peter

    2008-01-01

    Full Text Available Abstract Background HIV-1 R5 viruses cause most of the AIDS cases worldwide and are preferentially transmitted compared to CXCR4-using viruses. Furthermore, R5 viruses vary extensively in capacity to infect macrophages and highly macrophage-tropic variants are frequently identified in the brains of patients with dementia. Here, we investigated the sensitivity of R5 envelopes to a range of inhibitors and antibodies that block HIV entry. We studied a large panel of R5 envelopes, derived by PCR amplification without culture from brain, lymph node, blood and semen. These R5 envelopes conferred a wide range of macrophage tropism and included highly macrophage-tropic variants from brain and non-macrophage-tropic variants from lymph node. Results R5 macrophage-tropism correlated with sensitivity to inhibition by reagents that inhibited gp120:CD4 interactions. Thus, increasing macrophage-tropism was associated with increased sensitivity to soluble CD4 and to IgG-CD4 (PRO 542, but with increased resistance to the anti-CD4 monoclonal antibody (mab, Q4120. These observations were highly significant and are consistent with an increased affinity of envelope for CD4 for macrophage-tropic envelopes. No overall correlations were noted between R5 macrophage-tropism and sensitivity to CCR5 antagonists or to gp41 specific reagents. Intriguingly, there was a relationship between increasing macrophage-tropism and increased sensitivity to the CD4 binding site mab, b12, but decreased sensitivity to 2G12, a mab that binds a glycan complex on gp120. Conclusion Variation in R5 macrophage-tropism is caused by envelope variation that predominantly influences sensitivity to reagents that block gp120:CD4 interactions. Such variation has important implications for therapy using viral entry inhibitors and for the design of envelope antigens for vaccines.

  11. 巨噬细胞中脂多糖诱导微小RNA-155表达与地塞米松的抑制%Dexamethasone inhibits the expression of microRNA-155 in macrophages induced by lipopolysaccharide

    Institute of Scientific and Technical Information of China (English)

    王中华; 王首红; 吴岩; 李宙; 廖小龙; 覃铁和

    2016-01-01

    BACKGROUND:It is unclear about dexamethasone effect on the regulation of microRNA-155 expression in macrophages. OBJCTIVE:To explore whether dexamethasone can regulate the expression of microRNA-155 in macrophages. METHODS:(1) Lipopolysaccharide stimulation of mouse macrophages: mouse macrophage cel lines, Raw264.7 cels, were culturedin vitro and stimulated by lipopolysaccharide. Cultured cels were colected at 0, 0.5, 2, 6 hours after culture to detect the dynamical expression of microRNA-155. (2) Dexamethasone intervention for macrophages: Macrophages were divided into four groups: control group treated with phosphate buffer; lipopolysaccharide group stimulated by lipopolysaccharide; combined group given intervention with dexamethasone and lipopolysaccharide; dexamethasone group cultured with dexamethasone. At 6 hours after culture, cel supernatant was colected to detect the expression of tumor necrosis factor α and interleukin-6 using ELISA method. Real-time fluorescence quantitative PCR was used to detect the expression of microRNA-155 in the Raw264.7 macrophages. RESULTS AND CONCLUSION:Lipopolysaccharide significantly increased the expression of tumor necrosis factor α, interleukin-6 and microRNA-155 after 6 hours of culture (P   目的:了解地塞米松是否调节巨噬细胞中微小RNA-155的表达。  方法:①脂多糖刺激小鼠巨噬细胞:体外培养小鼠巨噬细胞株 Raw264.7细胞,予脂多糖刺激。分别在培养0,0.5,2,6 h收集细胞,检测miRNA-155的动态表达。②地塞米松对巨噬细胞的干预:实验分4组:对照组予磷酸盐缓冲液培养;脂多糖组予脂多糖刺激;地塞米松+脂多糖组予地塞米松和脂多糖共同作用;地塞米松组予地塞米松培养。6 h后收集培养上清用ELISA法检测培养液中肿瘤坏死因子α、白细胞介素6等炎症因子表达,用实时荧光定量PCR法检测巨噬细胞中微小RNA-155的表达。  结果与

  12. CD4~+CD25~+调节性T细胞对巨噬细胞泡沫化的影响%CD4~+ CD25~+ regulatory T cells inhibit macrophage-derived foam cells formation by down-regulating scavenger receptor expression

    Institute of Scientific and Technical Information of China (English)

    林静; 李大主

    2010-01-01

    of both CD36 and SRA in Tr-treated macrophage foam cells was significantly down-regulated. Conclusion Results collectively suggest that CD4~+ CD25~+ Tr cells may inhibit macrophage foam-cell formation, which is largely attributed to a down-regulated expression in scavenger receptor in Tr-treated macrophage foam cells.%目的 研究CD4~+ CD25~+调节性T细胞(Tr)对巨噬细胞泡沫化过程的影响及机制.方法 磁性细胞分离器(MACS)分离CD4~+ CD25~+ T细胞及CD4~+ CD25~- T细胞,在氧化型低密度脂蛋白(oxLDL)作用下,将巨噬细胞分别与CD4~+ CD25~+ T细胞、CD4~+ CD25~- T细胞共培养48 h.采用油红O染色和细胞内脂质测定的方法观察CD4~+ CD25~+ T细胞对巨噬细胞泡沫化的影响;采用RT-PCR、real-time PCR、Western blot的方法测定泡沫细胞清道夫受体(CD36和SRA)的表达.结果 与对照组比较,CD4~+ CD25~+ T细胞可显著抑制巨噬细胞脂质聚集及清道夫受体的表达.结论 CD4~+CD25~+ T细胞可显著抑制巨噬细胞泡沫化,其作用机制可能为下调清道夫受体的表达.

  13. Interactions outside the proteinase-binding loop contribute significantly to the inhibition of activated coagulation factor XII by its canonical inhibitor from corn.

    Science.gov (United States)

    Korneeva, Vera A; Trubetskov, Mikhail M; Korshunova, Alena V; Lushchekina, Sofya V; Kolyadko, Vladimir N; Sergienko, Olga V; Lunin, Vladimir G; Panteleev, Mikhail A; Ataullakhanov, Fazoil I

    2014-05-16

    Activated factor XII (FXIIa) is selectively inhibited by corn Hageman factor inhibitor (CHFI) among other plasma proteases. CHFI is considered a canonical serine protease inhibitor that interacts with FXIIa through its protease-binding loop. Here we examined whether the protease-binding loop alone is sufficient for the selective inhibition of serine proteases or whether other regions of a canonical inhibitor are involved. Six CHFI mutants lacking different N- and C-terminal portions were generated. CHFI-234, which lacks the first and fifth disulfide bonds and 11 and 19 amino acid residues at the N and C termini, respectively, exhibited no significant changes in FXIIa inhibition (Ki = 3.2 ± 0.4 nm). CHFI-123, which lacks 34 amino acid residues at the C terminus and the fourth and fifth disulfide bridges, inhibited FXIIa with a Ki of 116 ± 16 nm. To exclude interactions outside the FXIIa active site, a synthetic cyclic peptide was tested. The peptide contained residues 20-45 (Protein Data Bank code 1BEA), and a C29D substitution was included to avoid unwanted disulfide bond formation between unpaired cysteines. Surprisingly, the isolated protease-binding loop failed to inhibit FXIIa but retained partial inhibition of trypsin (Ki = 11.7 ± 1.2 μm) and activated factor XI (Ki = 94 ± 11 μm). Full-length CHFI inhibited trypsin with a Ki of 1.3 ± 0.2 nm and activated factor XI with a Ki of 5.4 ± 0.2 μm. Our results suggest that the protease-binding loop is not sufficient for the interaction between FXIIa and CHFI; other regions of the inhibitor also contribute to specific inhibition.

  14. Epigenetic regulation of macrophage polarization and inflammation by DNA methylation in obesity.

    Science.gov (United States)

    Wang, Xianfeng; Cao, Qiang; Yu, Liqing; Shi, Huidong; Xue, Bingzhong; Shi, Hang

    2016-11-17

    Obesity is associated with increased classically activated M1 adipose tissue macrophages (ATMs) and decreased alternatively activated M2 ATMs, both of which contribute to obesity-induced inflammation and insulin resistance. However, the underlying mechanism remains unclear. We find that inhibiting DNA methylation pharmacologically using 5-aza-2'-deoxycytidine or genetically by DNA methyltransferase 1 (DNMT1) deletion promotes alternative activation and suppresses inflammation in macrophages. Consistently, mice with myeloid DNMT1 deficiency exhibi